This file was created by the TYPO3 extension
bib
--- Timezone: CEST
Creation date: 2024-05-22
Creation time: 02-54-46
--- Number of references
401
article
WeissMPOBS2024
Improved Prediction of the Flow in Cylindrical Critical Flow Venturi Nozzles Using a Transitional Model
Flow, Turbulence and Combustion
2024
5
18
8.4,8.41
10.1007/s10494-024-00553-3
SWeiss
BMickan
JPolansky
KOberleithner
MBär
SSchmelter
article
vonKenneBN2024
Hydrodynamic synchronization of elastic cilia: How surface effects determine the characteristics of metachronal waves
Phys. Rev. E
2024
5
16
109
5
054407
8.4,8.41,8.43
10.1103/PhysRevE.109.054407
Avon Kenne
MBär
TNiedermayer
article
MarschallFSHE2024
Bayesian uncertainty evaluation applied to the tilted-wave interferometer
Opt. Express
2024
5
6
32
11
18664--18683
8.4,8.42,Form
10.1364/OE.524241
MMarschall
IFortmeier
MStavridis
FHughes
CElster
article
BernburgEK2024
Flexible Bayesian reliability demonstration testing
Applied Stochastic Models in Business and Industry
2024
4
26
8.4,8.42,Stichprobenverf
10.1002/asmb.2863
HBernburg
CElster
KKlauenberg
article
BocklerdMSSBKBWTTWGSG2024
Metrology infrastructure for high-pressure gas and liquified hydrogen flows. A brief outline of the MetHyInfra project, measurement challenges, and first results
Measurement
2024
4
7
232
8.41, 8.4, MetHyInfra
https://doi.org/10.1016/j.measurement.2024.114675
H.-B.Böckler
M.de Huu
R.Maury
S.Schmelter
M.D.Schakel
O.Büker
J.Kutin
G.Bobovnik
C.Wedler
J.P.M.Trusler
M.Thol
S.Weiss
C.Günz
D.Schumann
F.Gugole
article
AmanovaME2024
Finding the input features that reduce the entropy of a neural network’s prediction
Applied Intelligence
2024
1
25
8.4,8.42,ML
10.1007/s10489-024-05277-5
NAmanova
JMartin
CElster
article
10.3389/frai.2024.1330919
Benchmarking the influence of pre-training on explanation performance in MR image classification
Frontiers in Artificial Intelligence
2024
7
Convolutional Neural Networks (CNNs) are frequently and successfully used in medical prediction tasks. They are often used in combination with transfer learning, leading to improved performance when training data for the task are scarce. The resulting models are highly complex and typically do not provide any insight into their predictive mechanisms, motivating the field of “explainable” artificial intelligence (XAI). However, previous studies have rarely quantitatively evaluated the “explanation performance” of XAI methods against ground-truth data, and transfer learning and its influence on objective measures of explanation performance has not been investigated. Here, we propose a benchmark dataset that allows for quantifying explanation performance in a realistic magnetic resonance imaging (MRI) classification task. We employ this benchmark to understand the influence of transfer learning on the quality of explanations. Experimental results show that popular XAI methods applied to the same underlying model differ vastly in performance, even when considering only correctly classified examples. We further observe that explanation performance strongly depends on the task used for pre-training and the number of CNN layers pre-trained. These results hold after correcting for a substantial correlation between explanation and classification performance.
8.4,8.44
https://www.frontiersin.org/articles/10.3389/frai.2024.1330919
2624-8212
10.3389/frai.2024.1330919
MartaOliveira
RickWilming
BenedictClark
CélineBudding
FabianEitel
KerstinRitter
StefanHaufe
article
WinklerNFHLDB2023
Global Sensitivity Analysis and Uncertainty Quantification for Simulated Atrial Electrocardiograms
Metrology
2023
12
26
3
1
1-28
8.4,8.41,8.43, UQ
https://doi.org/10.3390/metrology3010001
BenjaminWinkler
ClaudiaNagel
NandoFarchmin
SebastianHeidenreich
AxelLoewe
OlafDössel
MarkusBär
article
MehariS2023
Towards Quantitative Precision for ECG Analysis: Leveraging State Space Models, Self-Supervision and Patient Metadata.
IEEE J Biomed Health Inform
2023
11
7
27
11
5326-5334
8.4, 8.41
10.1109/JBHI.2023.3310989
TemesgenMehari
NilsStrodthoff
article
KlauenbergGF2023
Propagation of conformity statements in compliance with the GUM and ISO 17025
Metrologia
2023
9
22
60
5
054004
8.4,8.42,Messunsicherheit
10.1088/1681-7575/acf3eb
KKlauenberg
JGreenwood
GFoyer
article
KastnerMHMPCWHRE2023
Compressed AFM-IR hyperspectral nanoimaging
Measurement Science and Technology
2023
9
21
8.4,8.42,LargeScaleDataAna,Regression
accepted
10.1088/1361-6501/acfc27
BKästner
MMarschall
AHornemann
SMetzner
PPatoka
SCortes
GWübbeler
AHoehl
ERühl
CElster
article
HegemannH2023
PyThia: A Python package for Uncertainty Quantification based on non-intrusive polynomial chaos expansions
Journal of Open Source Software
2023
9
15
8
89
5489
8.4,8.43,UQ
https://doi.org/10.21105/joss.05489
NandoHegemann
SebastianHeidenreich
article
FallerAvME2023
About the Generalizability of Deep Learning based Image Quality Assessment in Mammography
Machine Learning: Science and Technology
2023
9
12
8.4,8.42,ML
accepted
10.1088/2632-2153/acf914
JFaller
NAmanova
R Evan Engen
JMartin
CElster
article
GilletteGNBWWBSDPL2023
MedalCare-XL: 16,900 healthy and pathological synthetic 12 lead ECGs from electrophysiological simulations
Scientific Data
2023
8
8
10
531 (2023)
8.4,8.41,8.43
https://doi.org/10.1038/s41597-023-02416-4
KarliGillette
Matthias A. F.Gsell
ClaudiaNagel
JuleBender
BenjaminWinkler
Steven E.Williams
MarkusBär
TobiasSchäffter
OlafDössel
GernotPlank
AxelLoewe
article
WeissenbrunnerESS2023
A virtual flow meter downstream of various elbow configurations
Metrologia
2023
7
17
8.4,8.41,Flow, UQ
accepted
DOI 10.1088/1681-7575/ace7d6
AndreasWeissenbrunner
Ann-KathrinEkat
MartinStraka
SonjaSchmelter
article
MarschallWSE2023
Machine learning based priors for Bayesian inversion in MR imaging
Metrologia
2023
7
4
60
4
8.4,8.42,LargeScaleDataAna,ML
10.1088/1681-7575/ace3c2
MMarschall
GWübbeler
FSchmähling
CElster
article
BrahmaKMSK2023
Data-efficient Bayesian learning for radial dynamic MR reconstruction
Medical Physics
2023
6
27
8.4,8.42,ML,Messunsicherheit,LargeScaleDataAna
10.1002/mp.16543
SBrahma
CKolbitsch
JMartin
TSchäffter
AKofler
article
MarschallWBE2023
On modelling of artefact instability in interlaboratory comparisons
Metrologia
2023
6
26
8.4,8.42,KC,Messunsicherheit
accepted
10.1088/1681-7575/ace18f
MMarschall
GWübbeler
MBorys
CElster
article
KokDWE2023
Virtual experiments for the assessment of data analysis and uncertainty quantification methods in scatterometry
Metrologia
2023
5
19
8.4,8.42,Messunsicherheit,Form
accepted
10.1088/1681-7575/acd6fd
GKok
v MDijk
GWübbeler
CElster
article
StrodthoffMNASGKHDLBS2023
PTB-XL+, a comprehensive electrocardiographic feature dataset
Scientific Data
2023
5
13
10
279
8.4,8.41
https://doi.org/10.1038/s41597-023-02153-8
NilsStrodthoff
TemesgenMehari
ClaudiaNagel
Philip J.Aston
AshishSundar
ClausGraff
Jørgen K.Kanters
WilhelmHaverkamp
OlafDössel
AxelLoewe
MarkusBär
TobiasSchaeffter
article
EigelFHT2023
Adaptive Nonintrusive Reconstruction of Solutions to High-Dimensional Parametric PDEs
Methods and Algorithms for Scientific Computing
2023
4
30
45
2
A457-A479
8.4,8.43
https://doi.org/10.1137/21M1461988
MartinEigel
NandoFarchmin
SebastianHeidenreich
P.Trunschke
article
WeissPBOS2023
Derivation and validation of a reference data-based real gas model for hydrogen
Elsevier International Journal of Hydrogen Energy
2023
3
30
8.41,Flow
accepted
https://doi.org/10.1016/j.ijhydene.2023.03.073
S.Weiss
J.Polansky
M.Bär
K.Oberleithner
S.Schmelter
article
MarschallWSE2022
Generative models and Bayesian inversion using Laplace approximation
Computational Statistics
2023
3
16
8.4,8.42,ML,LargeScaleDataAna
10.1007/s00180-023-01345-5
MMarschall
GWübbeler
FSchmähling
CElster
article
WebnerPKS2023
Sensitivity analysis of threshold parameters in slug detection algorithms
International Journal of Multiphase Flow
2023
1
158
104278
8.41,8.4, Flow
10.1016/j.ijmultiphaseflow.2022.104278
10.1016/j.ijmultiphaseflow.2022.104278
F.Webner
J.Polansky
S.Knotek
S.Schmelter
article
cesnaite_alterations_2023
Alterations in rhythmic and non‐rhythmic resting‐state <prt>EEG</prt> activity and their link to cognition in older age
NeuroImage
2023
268
119810
8.4, 8.44
https://linkinghub.elsevier.com/retrieve/pii/S1053811922009314
2023-08-22
en
10538119
10.1016/j.neuroimage.2022.119810
ElenaCesnaite
PaulSteinfath
MinaJamshidi Idaji
TilmanStephani
DenizKumral
StefanHaufe
ChristianSander
TilmanHensch
UlrichHegerl
SteffiRiedel-Heller
SusanneRöhr
Matthias L.Schroeter
A．VeronicaWitte
ArnoVillringer
Vadim V.Nikulin
article
pellegrini_identifying_2023
Identifying good practices for detecting inter-regional linear functional connectivity from <prt>EEG</prt>
NeuroImage
2023
277
120218
8.4, 8.44
https://linkinghub.elsevier.com/retrieve/pii/S1053811923003695
2023-08-22
en
10538119
10.1016/j.neuroimage.2023.120218
FranziskaPellegrini
ArnaudDelorme
VadimNikulin
StefanHaufe
article
cai_bayesian_2023
Bayesian <prt>Algorithms</prt> for <prt>Joint</prt> <prt>Estimation</prt> of <prt>Brain</prt> <prt>Activity</prt> and <prt>Noise</prt> in <prt>Electromagnetic</prt> <prt>Imaging</prt>
IEEE Transactions on Medical Imaging
2023
42
3
762--773
8.4,8.44
https://ieeexplore.ieee.org/document/9932439/
2023-08-22
0278-0062, 1558-254X
10.1109/TMI.2022.3218074
ChangCai
HuicongKang
AliHashemi
DanChen
MithunDiwakar
StefanHaufe
KensukeSekihara
WeiWu
Srikantan S.Nagarajan
article
haufe_gait_2023
Gait <prt>Event</prt> <prt>Prediction</prt> <prt>Using</prt> <prt>Surface</prt> <prt>Electromyography</prt> in <prt>Parkinsonian</prt> <prt>Patients</prt>
Bioengineering
2023
10
2
212
Gait disturbances are common manifestations of Parkinson’s disease (PD), with unmet therapeutic needs. Inertial measurement units (IMUs) are capable of monitoring gait, but they lack neurophysiological information that may be crucial for studying gait disturbances in these patients. Here, we present a machine learning approach to approximate IMU angular velocity profiles and subsequently gait events using electromyographic (EMG) channels during overground walking in patients with PD. We recorded six parkinsonian patients while they walked for at least three minutes. Patient-agnostic regression models were trained on temporally embedded EMG time series of different combinations of up to five leg muscles bilaterally (i.e., tibialis anterior, soleus, gastrocnemius medialis, gastrocnemius lateralis, and vastus lateralis). Gait events could be detected with high temporal precision (median displacement of <prt>\textless</prt>50 ms), low numbers of missed events (<prt>\textless</prt>2%), and next to no false-positive event detections (<prt>\textless</prt>0.1%). Swing and stance phases could thus be determined with high fidelity (median F1-score of <prt>\textasciitilde</prt>0.9). Interestingly, the best performance was obtained using as few as two EMG probes placed on the left and right vastus lateralis. Our results demonstrate the practical utility of the proposed EMG-based system for gait event prediction, which allows the simultaneous acquisition of an electromyographic signal to be performed. This gait analysis approach has the potential to make additional measurement devices such as IMUs and force plates less essential, thereby reducing financial and preparation overheads and discomfort factors in gait studies.
8.4, 8.44
https://www.mdpi.com/2306-5354/10/2/212
2023-08-22
en
2306-5354
10.3390/bioengineering10020212
StefanHaufe
Ioannis U.Isaias
FranziskaPellegrini
ChiaraPalmisano
article
cai_bayesian_2023-1
Bayesian adaptive beamformer for robust electromagnetic brain imaging of correlated sources in high spatial resolution
IEEE Transactions on Medical Imaging
2023
1--1
8.4,8.44
https://ieeexplore.ieee.org/document/10068553/
2023-08-22
0278-0062, 1558-254X
10.1109/TMI.2023.3256963
ChangCai
YuanshunLong
SanjayGhosh
AliHashemi
YijingGao
MithunDiwakar
StefanHaufe
KensukeSekihara
WeiWu
Srikantan S.Nagarajan
article
del_vecchio_del_vecchio_pallidal_2023
Pallidal <prt>Recordings</prt> in <prt>Chronically</prt> <prt>Implanted</prt> <prt>Dystonic</prt> <prt>Patients</prt>: <prt>Mitigation</prt> of <prt>Tremor</prt>-<prt>Related</prt> <prt>Artifacts</prt>
Bioengineering
2023
10
4
476
Low-frequency oscillatory patterns of pallidal local field potentials (LFPs) have been proposed as a physiomarker for dystonia and hold the promise for personalized adaptive deep brain stimulation. Head tremor, a low-frequency involuntary rhythmic movement typical of cervical dystonia, may cause movement artifacts in LFP signals, compromising the reliability of low-frequency oscillations as biomarkers for adaptive neurostimulation. We investigated chronic pallidal LFPs with the PerceptTM PC (Medtronic PLC) device in eight subjects with dystonia (five with head tremors). We applied a multiple regression approach to pallidal LFPs in patients with head tremors using kinematic information measured with an inertial measurement unit (IMU) and an electromyographic signal (EMG). With IMU regression, we found tremor contamination in all subjects, whereas EMG regression identified it in only three out of five. IMU regression was also superior to EMG regression in removing tremor-related artifacts and resulted in a significant power reduction, especially in the theta-alpha band. Pallido-muscular coherence was affected by a head tremor and disappeared after IMU regression. Our results show that the Percept PC can record low-frequency oscillations but also reveal spectral contamination due to movement artifacts. IMU regression can identify such artifact contamination and be a suitable tool for its removal.
8.4, 8.44
https://www.mdpi.com/2306-5354/10/4/476
2023-08-22
en
2306-5354
10.3390/bioengineering10040476
JasminDel Vecchio Del Vecchio
IbrahemHanafi
Nicoló GabrielePozzi
PhilippCapetian
Ioannis U.Isaias
StefanHaufe
ChiaraPalmisano
phdthesis
Olbrich2022
Quantitative methods for the characterization of separated and intermittent multiphase flow patterns
2022
12
20
8.4, 8.41, flow
TU Berlin
https://doi.org/10.14279/depositonce-16659
MarcOlbrich
article
MartinE2021_2
Errors-in-Variables for deep learning: rethinking aleatoric uncertainty
Neural Processing Letters
2022
11
1
8.4,8.42,ML
1573-773X
10.1007/s11063-022-11066-3
JMartin
CElster
conference
SchmelterKOB2022
Comparison of different slug frequency calculation methods for the validation of two-phase flow simulations
2022
10
21
8.4,8.41,Flow
19th International Flow Measurement Conference (FLOMEKO)
Chongqing, China
19th International Flow Measurement Conference (FLOMEKO)
17-21.10.2022
S.Schmelter
S.Knotek
M.Olbrich
M.Bär
conference
WeissMOBS2022
Numerical investigation of boundary layer effects within cylindrical critical flow Venturi nozzles
2022
10
21
8.4,8.41,Flow
19th International Flow Measurement Conference (FLOMEKO)
Chongqing, China
19th International Flow Measurement Conference (FLOMEKO)
17-21.10.2022
S.Weiss
B.Mickan
K.Oberleithner
M.Bär
S.Schmelter
article
HufnagelMKAKSSK2022
3D model-based super-resolution motion-corrected cardiac T1 mapping
Physics in Medicine & Biology
2022
10
20
8.4,8.42
10.1088/1361-6560/ac9c40
SHufnagel
SMetzner
K MKerkering
C SAigner
AKofler
JSchulz-Menger
TSchäffter
CKolbitsch
conference
BocklerdMSSB2022
Metrology infrastructure for high-pressure gas and liquified hydrogen flows
2022
10
8.4,8.41,Flow
19th International Flow Measurement Conference (FLOMEKO)
Chongqing, China
19th International Flow Measurement Conference (FLOMEKO)
17-21.10.2022
H.-B.Böckler
M.de Huu
R.Maury
S.Schmelter
M.D.Schakel
O.Büker
article
MetznerKMWWBHRE2022
Assessment of Subsampling Schemes for Compressive Nano-FTIR Imaging
IEEE Transactions on Instrumentation and Measurement
2022
9
12
71
1-8
8.4,8.42,LargeScaleDataAna
10.1109/TIM.2022.3204072
SMetzner
BKästner
MMarschall
GWübbeler
SWundrack
ABakin
AHoehl
ERühl
CElster
article
OlbrichRKLvBOS2022
Deep learning based liquid level extraction from video observations of gas-liquid flows
International Journal of Multiphase Flow
2022
9
10
8.4,8.41,Flow,ML
https://doi.org/10.1016/j.ijmultiphaseflow.2022.104247
M.Olbrich
L.Riazy
T.Kretz
T.Leonard
D.S.van Putten
M.Bär
K.Oberleithner
S.Schmelter
article
BuranNB2022
Suppression of fibrillatory dynamics consisting of stable rotors by periodic pacing
New Journal of Physics
2022
8
23
24
August 2022
8.4,8.41
https://doi.org/10.1088/1367-2630/ac8571
P.Buran
T.Niedermayer
M.Bär
phdthesis
HarrenneeHoffmann2022
Investigating deep ensembles for the tilted-wave interferometer
2022
8
15
publiziert
8.4,8.42,ML,Form
https://depositonce.tu-berlin.de/bitstream/11303/17264/4/harren_lara.pdf
TU Berlin
PhD Thesis
10.14279/depositonce-16044
LHarren née Hoffmann
phdthesis
Worlitzer2022
Collective motion and clustering in active polar fluids
2022
8
10
8.4,8.43
https://www.depositonce.tu-berlin.de/bitstream/11303/17276/4/worlitzer_vasco.pdf
TU Berlin
PhD Thesis
http://dx.doi.org/10.14279/depositonce-16056
V. M.Worlitzer
article
SchmahlingME2021
A framework for benchmarking uncertainty in deep regression
Applied Intelligence
2022
8
9
8.4,8.42,ML
10.1007/s10489-022-03908-3
FrankoSchmähling
JörgMartin
ClemensElster
article
StrakaWKHS2022
Simulation Uncertainty for a Virtual Ultrasonic Flow Meter
Metrology
2022
7
18
2
3
335-359
8.41,8.4,Flow,UQ
https://doi.org/10.3390/metrology2030021
MartinStraka
AndreasWeissenbrunner
ChristianKoglin
ChristianHöhne
SonjaSchmelter
article
AmanovaME2022
Explainability for deep learning in mammography image quality assessment
Machine Learning: Science and Technology
2022
6
17
8.4,8.42,ML
accepted
10.1088/2632-2153/ac7a03
NAmanova
JMartin
CElster
article
WorlitzerJGBHEAB2022
Biophysical aspects underlying the swarm to biofilm transition
Science Advances
2022
6
15
8
24
8.4,8.43,ActFluid
DOI: 10.1126/sciadv.abn8152
V. M.Worlitzer
A.Jose
I.Grinberg
M.Bär
S.Heidenreich
A.Eldar
G.Ariel
A.Be´er
article
KokWE2022
Impact of Imperfect Artefacts and the Modus Operandi on
Uncertainty Quantification Using Virtual Instruments
Metrology
2022
6
12
2
311--319
8.4,8.42,Messunsicherheit,Form
10.3390/metrology2020019
GKok
GWübbeler
CElster
phdthesis
Farchmin2022
Adaptive and non-intrusive uncertainty quantification for high-dimensional parametric partial differential equations
2022
5
17
8.4,8.43
https://www.depositonce.tu-berlin.de/bitstream/11303/16752/4/farchmin_nando.pdf
TU Berlin
PhD Thesis
http://dx.doi.org/10.14279/depositonce-15530
N.Farchmin
article
HerrWZAFL2022
Spontaneous polarization and cell guidance on asymmetric nanotopography
Communications Physics
2022
5
11
5
114
8.4,8.43
https://doi.org/10.1038/s42005-022-00889-0
C.Herr
B.Winkler
F.Ziebert
I. S.Aranson
J. T.Fourkas
W.Losert
article
MetznerWKE2022
A comparison of two data analysis approaches for quantitative Magnetic Resonance Imaging
Measurement Science and Technology
2022
4
5
33
7
075401
8.4,8.42,LargeScaleDataAna
10.1088/1361-6501/ac5fff
SMetzner
GWübbeler
CKolbitsch
CElster
article
EigelGM2022
Low-rank tensor reconstruction of concentrated densities with application to Bayesian inversion
Statistics and Computing
2022
3
12
32
2
27
8.4,8.42
10.1007/s11222-022-10087-1
MEigel
RGruhlke
MMarschall
article
WubbelerMKHHE2022
GUM-Compliant Uncertainty Evaluation Using Virtual Experiments
Metrology
2022
3
1
2
1
114--127
8.42,8.4,Form
10.3390/metrology2010008
GWübbeler
MMarschall
KKniel
DHeißelmann
FHärtig
CElster
article
PolanskyS2022
Implementation of turbulence damping in the OpenFOAM multiphase flow solver interFoam
Archives of Thermodynamics
2022
3
1
43
1
21-43
Multiphase flow, Stratified flow, Turbulence damping, Computational fluid dynamics, OpenFOAM, Reynolds-averaged Navier–Stokes, Detached eddy simulation, Delayed detached eddy simulation
8.4,8.41,Flow
http://journals.pan.pl/Content/122890/PDF/art02_internet.pdf
10.24425/ather.2022.140923
JiriPolansky
SonjaSchmelter
article
MarschallSSE2022
Uncertainty propagation in quantitative magnetic force microscopy using a Monte-Carlo method
IEEE Transactions on Magnetics
2022
2
21
1--1
8.4,8.42,Messunsicherheit
10.1109/TMAG.2022.3153176
MMarschall
SSievers
H WSchumacher
CElster
article
ScholzFMSSE2022
Experimental Design for
Virtual Experiments in Tilted-Wave
Interferometry
Metrology
2022
2
17
2
84--97
8.4,8.42,Form
doi.org/10.3390/metrology2010006
GScholz
IFortmeier
MMarschall
MStavridis
MSchulz
CElster
article
MarschallWE2022
Rejection sampling for Bayesian uncertainty evaluation using the Monte Carlo techniques of GUM-S1
Metrologia
2022
2
1
59
1
015004
8.4,8.42,Messunsicherheit
10.1088/1681-7575/ac3920
MMarschall
GWübbeler
CElster
article
GruberDSEE2022
Discrete wavelet transform on uncertain data: Efficient online implementation for practical applications.
Advanced Mathematical and Computational Tools in Metrology and Testing XII, Series on Advances in Mathematics for Applied Sciences
2022
1
30
90
8.4,8.42,Messunsicherheit
978-981-1242-37-3
MGruber
TDorst
ASchütze
SEichstädt
CElster
article
ReinkenHBK2022
Ising-like critical behavior of vortex lattices in an active fluid
Physical Review Letters
2022
1
27
128
4
048004
8.4,8.43,ActFluid
10.1103/PhysRevLett.128.048004
HReinken
SHeidenreich
MBär
S.H.LKlapp
article
FortmeierS2022
Development of a metrological reference system for the form measurement of aspheres and freeform surfaces based on a tilted-wave interferometer
Measurement Science and Technology
2022
1
24
33
4
8.4,8.42,Form
accepted
10.1088/1361-6501/ac47bd
IFortmeier
MStavridis
MSchulz
CElster
article
cai_empirical_2022
Empirical <prt>Bayesian</prt> localization of event-related time-frequency neural activity dynamics
NeuroImage
2022
258
119369
8.4, 8.44
https://linkinghub.elsevier.com/retrieve/pii/S1053811922004888
2022-09-13
en
10538119
10.1016/j.neuroimage.2022.119369
ChangCai
LeightonHinkley
YijingGao
AliHashemi
StefanHaufe
KensukeSekihara
Srikantan S.Nagarajan
article
langer_benchmark_2022
A benchmark for prediction of psychiatric multimorbidity from resting <prt>EEG</prt> data in a large pediatric sample
NeuroImage
2022
258
119348
8.4, 8.44
https://linkinghub.elsevier.com/retrieve/pii/S1053811922004670
2022-09-13
en
10538119
10.1016/j.neuroimage.2022.119348
NicolasLanger
Martyna BeataPlomecka
MariusTröndle
AnujaNegi
TzvetanPopov
MichaelMilham
StefanHaufe
article
wilming_scrutinizing_2022
Scrutinizing <prt>XAI</prt> using linear ground-truth data with suppressor variables
Machine Learning
2022
111
5
1903--1923
Abstract Machine learning (ML) is increasingly often used to inform high-stakes decisions. As complex ML models (e.g., deep neural networks) are often considered black boxes, a wealth of procedures has been developed to shed light on their inner workings and the ways in which their predictions come about, defining the field of ‘explainable AI’ (XAI). Saliency methods rank input features according to some measure of ‘importance’. Such methods are difficult to validate since a formal definition of feature importance is, thus far, lacking. It has been demonstrated that some saliency methods can highlight features that have no statistical association with the prediction target (suppressor variables). To avoid misinterpretations due to such behavior, we propose the actual presence of such an association as a necessary condition and objective preliminary definition for feature importance. We carefully crafted a ground-truth dataset in which all statistical dependencies are well-defined and linear, serving as a benchmark to study the problem of suppressor variables. We evaluate common explanation methods including LRP, DTD, PatternNet, PatternAttribution, LIME, Anchors, SHAP, and permutation-based methods with respect to our objective definition. We show that most of these methods are unable to distinguish important features from suppressors in this setting.
8.4, 8.44
https://link.springer.com/10.1007/s10994-022-06167-y
2022-09-13
en
0885-6125, 1573-0565
10.1007/s10994-022-06167-y
RickWilming
CélineBudding
Klaus-RobertMüller
StefanHaufe
article
kumral_relationship_2022
Relationship between regional white matter hyperintensities and alpha oscillations in older adults
Neurobiology of Aging
2022
112
1--11
8.4, 8.44
https://linkinghub.elsevier.com/retrieve/pii/S0197458021003195
2022-09-13
en
01974580
10.1016/j.neurobiolaging.2021.10.006
DenizKumral
ElenaCesnaite
FraukeBeyer
Simon M.Hofmann
TilmanHensch
ChristianSander
UlrichHegerl
StefanHaufe
ArnoVillringer
A. VeronicaWitte
Vadim V.Nikulin
article
merk_machine_2022
Machine learning based brain signal decoding for intelligent adaptive deep brain stimulation
Experimental Neurology
2022
351
113993
8.4, 8.44
https://linkinghub.elsevier.com/retrieve/pii/S0014488622000188
2022-09-13
en
00144886
10.1016/j.expneurol.2022.113993
TimonMerk
VictoriaPeterson
RichardKöhler
StefanHaufe
R. MarkRichardson
Wolf-JulianNeumann
article
hashemi_joint_2022
Joint <prt>Learning</prt> of <prt>Full</prt>-structure <prt>Noise</prt> in <prt>Hierarchical</prt> <prt>Bayesian</prt> <prt>Regression</prt> <prt>Models</prt>
IEEE Transactions on Medical Imaging
2022
1--1
8.4, 8.44
https://ieeexplore.ieee.org/document/9963991/
2023-08-22
0278-0062, 1558-254X
10.1109/TMI.2022.3224085
AliHashemi
ChangCai
YijingGao
SanjayGhosh
Klaus-RobertMüller
Srikantan S.Nagarajan
StefanHaufe
article
pellegrini_p_2022
P 80 <prt>How</prt> to avoid measurement of spurious inter-regional functional connectivity from <prt>EEG</prt> – a simulation study
Clinical Neurophysiology
2022
137
e60--e61
8.4, 8.44
https://linkinghub.elsevier.com/retrieve/pii/S1388245722001298
2023-08-22
en
13882457
10.1016/j.clinph.2022.01.111
F.Pellegrini
V.Nikulin
S.Haufe
article
noauthor_erratum:_2022
Erratum: <prt>Stephani</prt> et al., “<prt>Temporal</prt> <prt>Signatures</prt> of <prt>Criticality</prt> in <prt>Human</prt> <prt>Cortical</prt> <prt>Excitability</prt> as <prt>Probed</prt> by <prt>Early</prt> <prt>Somatosensory</prt> <prt>Responses</prt>”
The Journal of Neuroscience
2022
42
22
4605--4605
8.4, 8.44
https://www.jneurosci.org/lookup/doi/10.1523/JNEUROSCI.0820-22.2022
2023-08-22
en
0270-6474, 1529-2401
10.1523/JNEUROSCI.0820-22.2022
article
palmisano_gait_2022
Gait <prt>Initiation</prt> <prt>Impairment</prt> in <prt>Patients</prt> with <prt>Parkinson</prt>’s <prt>Disease</prt> and <prt>Freezing</prt> of <prt>Gait</prt>
Bioengineering
2022
9
11
639
Freezing of gait (FOG) is a sudden episodic inability to produce effective stepping despite the intention to walk. It typically occurs during gait initiation (GI) or modulation and may lead to falls. We studied the anticipatory postural adjustments (imbalance, unloading, and stepping phase) at GI in 23 patients with Parkinson’s disease (PD) and FOG (PDF), 20 patients with PD and no previous history of FOG (PDNF), and 23 healthy controls (HCs). Patients performed the task when off dopaminergic medications. The center of pressure (CoP) displacement and velocity during imbalance showed significant impairment in both PDNF and PDF, more prominent in the latter patients. Several measurements were specifically impaired in PDF patients, especially the CoP displacement along the anteroposterior axis during unloading. The pattern of segmental center of mass (SCoM) movements did not show differences between groups. The standing postural profile preceding GI did not correlate with outcome measurements. We have shown impaired motor programming at GI in Parkinsonian patients. The more prominent deterioration of unloading in PDF patients might suggest impaired processing and integration of somatosensory information subserving GI. The unaltered temporal movement sequencing of SCoM might indicate some compensatory cerebellar mechanisms triggering time-locked models of body mechanics in PD.
8.4, 8.44
https://www.mdpi.com/2306-5354/9/11/639
2023-08-22
en
2306-5354
10.3390/bioengineering9110639
ChiaraPalmisano
LauraBeccaria
StefanHaufe
JensVolkmann
GianniPezzoli
Ioannis U.Isaias
article
WubbelerMRKE2021
Compressive nano-FTIR chemical mapping
Measurement Science and Technology
2021
12
24
33
035402
8.4,8.42,LargeScaleDataAna,Regression
accepted
10.1088/1361-6501/ac407a
GWübbeler
MMarschall
ERühl
BKästner
CElster
article
MehariS2021
Self-supervised representation learning from 12-lead ECG data
Computers in Biology and Medicine
2021
12
18
141
105114
8.4,8.41,ML
https://doi.org/10.1016/j.compbiomed.2021.105114
TMehari
NStrodthoff
phdthesis
Metzner2021
Bayesian data analysis for magnetic resonance fingerprinting
2021
12
7
publiziert
8.4,8.42,Messunsicherheit,Regression,Fingerprinting,LargeScaleDataAna
TU Berlin
PhD Thesis
10.14279/depositonce-12455
SMetzner
article
WilczekHB2021
Die Physik aktiver Fluide
Physik Journal
2021
12
1
20
12
35
8.4,8.43
MWilczek
SHeidenreich
MBär
article
HoffmannFE2021_2
Deep learning for tilted-wave interferometry
tm - Technisches Messen
2021
11
20
publiziert
8.4,8.42,Form,ML
10.1515/teme-2021-0103
LHoffmann
IFortmeier
CElster
article
WorlitzerABSBH2021
Turbulence-induced clustering in compressible active fluids
Soft Matter
2021
11
11
2021
17
10447-10457
8.4,8.43,ActFluid
https://doi.org/10.1039/D1SM01276B
V MWorlitzer
GAriel
ABe'er
HStark
MBär
SHeidenreich
article
KlauenbergMBCvE2021
The GUM perspective on straight-line errors-in-variables regression
Measurement
2021
11
6
187
110340
8.4,8.42,Regression
0263-2241
10.1016/j.measurement.2021.110340
KKlauenberg
SMartens
ABošnjaković
M.GCox
A. M.Hvan der Veen
CElster
article
AntonREMSSE2021
The regression detectability index RDI for mammography images of breast phantoms with calcification-like objects and anatomical background
Physics in Medicine & Biology
2021
10
27
8.4,8.42
10.1088/1361-6560/ac33ea
MAnton
MReginatto
CElster
UMäder
SSchopphoven
ISechopoulos
RE van Engen
article
KhmelinskaiaFYPS2021
Membrane-Mediated Self-Organization of Rod-Like DNA Origami on Supported Lipid Bilayers
Advanced Materials Interfaces
2021
10
18
8
24
2101094
8.4, 8.41
https://doi.org/10.1002/admi.202101094
AKhmelinskaia
H GFranquelim
RYaadav
E PPetrov
PSchwille
article
FischedickSBE2020
Investigation of the uncertainty contributions of the alignment of PTB's double-ended interferometer by virtual experiments
Metrologia
2021
10
12
58
6
064001
8.4,8.42,Form
10.1088/1681-7575/ac2724
MarkusFischedick
ManuelStavridis
GuidoBartl
ClemensElster
article
KnotekSO2021
Assessment of different parameters used in mesh independence studies in two-phase slug flow simulations
Measurement: Sensors
2021
9
28
18
100317
8.4,8.41,Flow
2665-9174
10.1016/j.measen.2021.100317
StanislavKnotek
SonjaSchmelter
MarcOlbrich
article
SchmelterOKB2021
Analysis of multiphase flow simulations and comparison with high-speed video observations
Measurement: Sensors
2021
9
23
18
100154
8.4,8.41,Flow
2665-9174
10.1016/j.measen.2021.100154
SonjaSchmelter
MarcOlbrich
StanislavKnotek
MarkusBär
article
OlbrichHLSBOS2021
Comparing temporal characteristics of slug flow from tomography measurements and video observations
Measurement: Sensors
2021
9
22
18
100222
8.4,8.41,Flow
2665-9174
10.1016/j.measen.2021.100222
MarcOlbrich
AndrewHunt
TerriLeonard
DennisS. van Putten
MarkusBär
KilianOberleithner
SonjaSchmelter
article
HoffmannFE2021
Uncertainty Quantification by Ensemble Learning for Computational Optical Form Measurements
Machine Learning: Science and Technology
2021
5
24
publiziert
8.4,8.42,ML,Form
10.1088/2632-2153/ac0495
LHoffmann
IFortmeier
CElster
article
MartinE2021
GUI for Bayesian sample size planning in type A uncertainty evaluation
Measurement Science and Technology
2021
4
30
32
7
5005
8.4,8.42,Messunsicherheit
10.1088/1361-6501/abe2bd
JMartin
CElster
article
AndrleFHHSS2021
Invertible Neural Networks Versus MCMC for Posterior Reconstruction in Grazing Incidence X-Ray Fluorescence
Scale Space and Variational Methods in Computer Vision
2021
4
30
528--539
8.4, 8.43, UQ
10.1007/978-3-030-75549-2_42
AAndrle
NFarchmin
PHagemann
SHeidenreich
VSoltwisch
GSteidl
article
LeydenUMYPGPBA2021
Rac1 activation can generate untemplated, lamellar membrane ruffles
BMC Biology
2021
4
13
19
72
8.4,8.41
https://doi.org/10.1186/s12915-021-00997-3
F.Leyden
S.Uthishtran
U. K.Moorthi
H. M.York
A.Patil
H.Gandhi
Eugene. P.Petrov
T.Bornschlögl
S.Arumugam
article
PeledRHBAB2021
Heterogeneous bacterial swarms with mixed lengths
Physical Review E
2021
3
29
103
3
032413
8.4,8.43,ActFluid
10.1103/PhysRevE.103.032413
SPeled
S DRyan
SHeidenreich
MBär
GAriel
ABe'er
article
KlauenbergME2021
Hypothesis-based acceptance sampling for modules F and F1 of the European Measuring Instruments Directive
Statistics and Public Policy
2021
3
10
8.4,8.42,Stichprobenverf
10.1080/2330443X.2021.1900762
KKlauenberg
C AMüller
CElster
article
WorlitzerABSB2021
Motility-induced clustering and meso-scale turbulence in active polar fluids
New Journal of Physics
2021
3
10
23
033012
8.4,ActFluid
10.1088/1367-2630/abe72d
V MWorlitzer
GAriel
ABe'er
HStark
MBär
SHeidenreich
article
MetznerWFGKE2021
Bayesian uncertainty quantification for magnetic resonance fingerprinting
Physics in Medicine & Biology
2021
3
1
66
7
075006
8.4,8.42,Messunsicherheit,Regression,Fingerprinting,LargeScaleDataAna
10.1088/1361-6560/abeae7
SMetzner
GWübbeler
SFlassbeck
CGatefait
CKolbitsch
CElster
article
AndrleHVQSHSS2021
The anisotropy in the optical constants of quartz crystals for soft X-rays
Journal of Applied Crystallography
2021
2
19
54
2
402--408
8.4, 8.43, UQ
10.1107/S1600576720016325
AAndrle
PHönicke
JVinson
RQuintanilha
QSaadeh
SHeidenreich
FScholze
VSoltwisch
article
SmudaGHN2021
Function of Hemoglobin-Based Oxygen Carriers: Determination of Methemoglobin Content by Spectral Extinction Measurements
Int J Mol Sci .
2021
2
10
22
4
1753
8.4,8.41,Cyto
10.3390/ijms22041753
KSmuda
JGienger
PHönicke
JNeukammer
article
SchmelterKOFB2021
On the influence of inlet perturbations on slug dynamics inhorizontal multiphase flow a computational study
Metrologia
2021
1
21
58
1
014003
8.4,8.41,Flow
10.1088/1681-7575/abd1c9
SSchmelter
SKnotek
MOlbrich
AFiebach
MBär
article
WubbelerE2020_2
Efficient experimental sampling through low-rank matrix recovery
Metrologia
2021
1
7
58
1
014002
online
8.4,8.42,Regression,LargeScaleDataAna
accepted
10.1088/1681-7575/abc97b
GWübbeler
CElster
article
SchmidtFSSLS2021
The impact of 4D flow displacementartifacts on wall shear stress estimation
Magnetic Resonance in Medicine
2021
85
6
3154-3168
8.4,8.41,Flow
10.1002/mrm.28641
SSchmidt
SFlassbeck
SSchmelter
ESchmeyer
M ELadd
SSchmitter
article
oala_machine_2021
Machine <prt>Learning</prt> for <prt>Health</prt>: <prt>Algorithm</prt> <prt>Auditing</prt> & <prt>Quality</prt> <prt>Control</prt>
Journal of Medical Systems
2021
45
12
105
Abstract Developers proposing new machine learning for health (ML4H) tools often pledge to match or even surpass the performance of existing tools, yet the reality is usually more complicated. Reliable deployment of ML4H to the real world is challenging as examples from diabetic retinopathy or Covid-19 screening show. We envision an integrated framework of algorithm auditing and quality control that provides a path towards the effective and reliable application of ML systems in healthcare. In this editorial, we give a summary of ongoing work towards that vision and announce a call for participation to the special issue Machine Learning for Health: Algorithm Auditing & Quality Control in this journal to advance the practice of ML4H auditing.
8.4, 8.44
https://link.springer.com/10.1007/s10916-021-01783-y
2022-09-13
en
0148-5598, 1573-689X
10.1007/s10916-021-01783-y
LuisOala
Andrew G.Murchison
PradeepBalachandran
ShrutiChoudhary
JanaFehr
Alixandro WerneckLeite
Peter G.Goldschmidt
ChristianJohner
Elora D. M.Schörverth
RoseNakasi
MartinMeyer
FedericoCabitza
PatBaird
CarolinPrabhu
EvaWeicken
XiaoxuanLiu
MarkusWenzel
SteffenVogler
DarlingtonAkogo
ShadaAlsalamah
EmreKazim
AdrianoKoshiyama
SvenPiechottka
SheenaMacpherson
IanShadforth
ReginaGeierhofer
ChristianMatek
JoachimKrois
BrunoSanguinetti
MatthewArentz
PavolBielik
SaulCalderon-Ramirez
AussAbbood
NicolasLanger
StefanHaufe
FerathKherif
SameerPujari
WojciechSamek
ThomasWiegand
article
hashemi_unification_2021
Unification of sparse <prt>Bayesian</prt> learning algorithms for electromagnetic brain imaging with the majorization minimization framework
NeuroImage
2021
239
118309
8.4, 8.44
https://linkinghub.elsevier.com/retrieve/pii/S1053811921005851
2022-09-13
en
10538119
10.1016/j.neuroimage.2021.118309
AliHashemi
ChangCai
GittaKutyniok
Klaus-RobertMüller
Srikantan S.Nagarajan
StefanHaufe
article
cai_robust_2021
Robust estimation of noise for electromagnetic brain imaging with the champagne algorithm
NeuroImage
2021
225
117411
8.4, 8.44
https://linkinghub.elsevier.com/retrieve/pii/S105381192030896X
2022-09-13
en
10538119
10.1016/j.neuroimage.2020.117411
ChangCai
AliHashemi
MithunDiwakar
StefanHaufe
KensukeSekihara
Srikantan S.Nagarajan
article
lichtner_predicting_2021
Predicting lethal courses in critically ill <prt>COVID</prt>-19 patients using a machine learning model trained on patients with non-<prt>COVID</prt>-19 viral pneumonia
Scientific Reports
2021
11
1
13205
Abstract In a pandemic with a novel disease, disease-specific prognosis models are available only with a delay. To bridge the critical early phase, models built for similar diseases might be applied. To test the accuracy of such a knowledge transfer, we investigated how precise lethal courses in critically ill COVID-19 patients can be predicted by a model trained on critically ill non-COVID-19 viral pneumonia patients. We trained gradient boosted decision tree models on 718 (245 deceased) non-COVID-19 viral pneumonia patients to predict individual ICU mortality and applied it to 1054 (369 deceased) COVID-19 patients. Our model showed a significantly better predictive performance (AUROC 0.86 [95% CI 0.86–0.87]) than the clinical scores APACHE2 (0.63 [95% CI 0.61–0.65]), SAPS2 (0.72 [95% CI 0.71–0.74]) and SOFA (0.76 [95% CI 0.75–0.77]), the COVID-19-specific mortality prediction models of Zhou (0.76 [95% CI 0.73–0.78]) and Wang (laboratory: 0.62 [95% CI 0.59–0.65]; clinical: 0.56 [95% CI 0.55–0.58]) and the 4C COVID-19 Mortality score (0.71 [95% CI 0.70–0.72]). We conclude that lethal courses in critically ill COVID-19 patients can be predicted by a machine learning model trained on non-COVID-19 patients. Our results suggest that in a pandemic with a novel disease, prognosis models built for similar diseases can be applied, even when the diseases differ in time courses and in rates of critical and lethal courses.
8.4, 8.44
http://www.nature.com/articles/s41598-021-92475-7
2022-09-13
en
2045-2322
10.1038/s41598-021-92475-7
GregorLichtner
FelixBalzer
StefanHaufe
NiklasGiesa
FridtjofSchiefenhövel
MalteSchmieding
CarloJurth
WolfgangKopp
AltunaAkalin
Stefan J.Schaller
SteffenWeber-Carstens
ClaudiaSpies
Falkvon Dincklage
article
EigelFHT2021
Efficient approximation of high-dimensional exponentials by
tensornetworks
International Journal of Uncertainty Quantification
2021
25-51
8.4,8.43,UQ
10.1615/Int.J.UncertaintyQuantification.2022039164
M.Eigel
N.Farchmin
S.Heidenreich
P.Trunschke
article
MarschallHWHRKE2020
Compressed FTIR spectroscopy using low-rank matrix reconstruction
Opt. Express
2020
12
10
26
28
38762--38772
8.4,8.42,Regression,LargeScaleDataAna
10.1364/OE.404959
MMarschall
AHornemann
GWübbeler
AHoehl
ERühl
BKästner
CElster
article
MartinE2020_3
Detecting unusual input to neural networks
Appl Intell
2020
10
30
publiziert
8.4,8.42,ML
10.1007/s10489-020-01925-8
JMartin
CElster
article
WubbelerME2020
A simple method for Bayesian uncertainty evaluation in linear models
Metrologia
2020
10
21
57
6
065010
8.4,8.42,Unsicherheit
10.1088/1681-7575/aba3b8
GWübbeler
MMarschall
CElster
article
OlbrichSBSOS2020
Identification of coherent structures in horizontal slug flow
Flow Measurement and Instrumentation
2020
10
16
76
101814
8.4,8.41,Flow
10.1016/j.flowmeasinst.2020.101814
MOlbrich
ESchmeyer
MBär
MSieber
KOberleithner
SSchmelter
phdthesis
Kretz2020
Development of model observers for quantitative assessment of mammography image quality
2020
10
7
publiziert
8.4,8.42,ML
http://dx.doi.org/10.14279/depositonce-10552
TU Berlin
PhD Thesis
TKretz
article
HoffmannE2020
Deep Neural Networks for Computational Optical Form Measurements
Journal of Sensors and Sensor Systems
2020
9
24
9
301--307
publiziert
8.4,8.42,ML,Form
10.5194/jsss-9-301-2020
LHoffmann
CElster
article
OlbrichBOS2020
Statistical characterization of horizontal slug flow using snapshot proper orthogonal decomposition
International Journal of Multiphase Flow
2020
9
6
134
103453
8.4,8.41,Flow
10.1016/j.ijmultiphaseflow.2020.103453
MOlbrich
MBär
KOberleithner
SSchmelter
article
MartinE2020_2
The variation of the posterior variance and Bayesian sample size determination
Statistical Methods & Applications
2020
8
25
1613-981X
8.4,8.42,Unsicherheit
10.1007/s10260-020-00545-3
JMartin
CElster
article
DemeyerFE2020
Guidance on Bayesian uncertainty evaluation for a class of GUM measurement models
Metrologia
2020
8
18
8.4,8.42,Unsicherheit
10.1088/1681-7575/abb065
SDemeyer
NFischer
CElster
article
ElsterK2020
A quantile inequality for location-scale distributions
Statistics & Probability Letters
2020
6
20
165
108851
8.4,8.42,Stichprobenverf
/10.1016/j.spl.2020.108851
CElster
KKlauenberg
article
ReinkenNHSBKA2020
Organizing bacterial vortex lattices by periodic obstacle arrays
Commun Phys
2020
5
7
3
76
8.4,8.43,ActFluid
10.1038/s42005-020-0337-z
HReinken
DNishiguchi
SHeidenreich
ASokolov
MBär
S H LKlapp
I SAranson
article
FarchminHSWBBH2020
Efficient Bayesian inversion for shape reconstruction of lithography masks
Journal of Micro/Nanolithography, MEMS, and MOEMS
2020
5
5
2
19
1--11
8.4,8.43,UQ,Scatter-Inv
10.1117/1.JMM.19.2.024001
NFarchmin
MHammerschmidt
P ISchneider
MWurm
BBodermann
MBär
SHeidenreich
article
AntonVHE2020
RDI - a regression detectability index for quality assurance in: x-ray imaging
Physics in Medicine & Biology
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4
23
65
8
085017
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10.1088/1361-6560/ab7b2e
MAnton
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KretzMSE2020
Mammography Image Quality Assurance Using Deep Learning
IEEE Transactions on Biomedical Engineering
2020
4
14
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10.1109/TBME.2020.2983539
TKretz
K-RMüller
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CElster
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BartlEMSVW2020
Thermal expansion and compressibility of single-crystal silicon between 285 K and 320 K
Measurement Science and Technology
2020
4
3
31
6
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10.1088/1361-6501/ab7359
GBartl
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JMartin
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BeaerIGKHBA2020
A phase diagram for bacterial swarming
Commun Phys
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4
3
3
66
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ABe´er
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SHeidenreich
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MartinE2020
Inspecting adversarial examples using the fisher information
Neurocomputing
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3
21
382
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JMartin
CElster
conference
CasforZapataFPNSHLKS2020
Sensitivity analysis for the detection of pitchwalk in self-
aligned quadruple patterning by GISAXS
2020
3
20
11325
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SPIE
Proc. of SPIE
San Jose, USA
Metrology, Inspection, and Process Control for Microlithography XXXIV
20.03.2020
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M.Casfor Zapata
N.Farchmin
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K.Nikolaev
V.Soltwisch
S.Heidenreich
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SchmelterOSB2020
Numerical simulation, validation, and analysis of two-phase slug flow in large horizontal pipes
Flow Measurement and Instrumentation
2020
3
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73
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SSchmelter
MOlbrich
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Effects of misalignments on the modulation transfer function measurement of camera lenses analyzed in optomechanical simulations
Opt. Eng.
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BarGHP2020
Self-Propelled Rods: Insights and Perspectives for Active Matter
Annual Review of Condensed Matter Physics
2020
3
1
11
441--466
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10.1146/annurev-conmatphys-031119-050611
MBär
RGroßmann
SHeidenreich
FPeruani
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WubbelerE2020
On the transferability of the GUM-S1 type A uncertainty
Metrologia
2020
1
23
57
1
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GWübbeler
CElster
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FortmeierSLMSHBBKSE2019
Round robin comparison study on the form measurement of optical freeform surfaces
Journal of the European Optical Society-Rapid Publications
2020
1
8
16
2
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10.1186/s41476-019-0124-1
InesFortmeier
ReykoSchachtschneider
VitLedl
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JensSiepmann
AntoniaHarsch
RolfBeisswanger
YouichiBitou
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Large-Scale Bayesian Spatial-Temporal Regression with Application to Cardiac MR-Perfusion Imaging
SIAM J. Imaging Sci.
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Testing normality - An introduction with sample size calculation in legal metrology
tm - Technisches Messen
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86
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KKlauenberg
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About not Correcting for Systematic Effects
Measurement Science Review
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5
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KKlauenberg
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GiengerGOBN2019
Assessment of deformation of human red blood cells in flow cytometry: measurement and simulation of bimodal forward scatter distributions
Biomedical Optics Express
2019
9
1
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9
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Approximate large-scale Bayesian spatial modeling with application to quantitative magnetic resonance imaging
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29
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SMetzner
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CElster
article
SchmelterOSB2019
Numerical simulation, validation, and analysis of two-phase slug flow in large horizontal pipes
Proceedings of the 18th International Flow Measurement Conference FLOMEKO 2019
2019
7
1
8.4,8.41,Flow
SSchmelter
MOlbrich
ESchmeyer
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OlbrichSBSOS2019
Identification of coherent structures in horizontal slug flow
Proceedings of the 18th International Flow Measurement Conference FLOMEKO 2019
2019
7
1
8.4,8.41,Flow
MOlbrich
ESchmeyer
MBär
MSieber
KOberleithner
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KretzASE2019
Determination of contrast-detail curves in mammography image quality assessment by a parametric model observer
Physica Medica
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5
20
62
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TKretz
MAnton
TSchäffter
CElster
article
KulawiakLBE2019
Active poroelastic two-phase model for the motion of Physarum microplasmodia
PLoS One
2019
5
14
14
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10.1101/638312
D AKulawiak
JLöber
MBär
HEngel
article
RiazySOAvNS2019
Porous medium 3D flow simulation of contrast media washout in cardiac MRI reflects myocardial injury
Magnetic Resonance in Medicine
2019
4
16
advance online publication
8.4,8.41, flow
10.1002/mrm.27756
LRiazy
TSchäffter
MOlbrich
J ASchueler
Fv. Knobelsdorff-Brenkenhoff
TNiendorf
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GiengerSMBN2019
Refractive index of human red blood cells between 290 nm and 1100 nm determined by optical extinction measurements
Scientific Reports
2019
3
15
9
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JGienger
KSmuda
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MBär
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AlvesdBd2019
Simulation of the Perfusion of Contrast Agent Used in Cardiac Magnetic Resonance: A Step Toward Non-invasive Cardiac Perfusion Quantification
Front. Physiol.
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J. RAlves
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SchachtschneiderSFSE2019
SimOptDevice: a library for virtual optical experiments
Journal of Sensors and Sensor Systems
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2
27
8
1
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RSchachtschneider
MStavridis
IFortmeier
MSchulz
CElster
article
MartinBE2019
Application of Bayesian model averaging to the determination of thermal expansion of single-crystal silicon
Measurement Science and Technology
2019
2
21
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045012
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10.1088/1361-6501/ab094b
JMartin
GBartl
CElster
article
ReinkenHBK2019
Anisotropic mesoscale turbulence and pattern formation in microswimmer suspensions induced by orienting external fields
New Journal of Physics
2019
1
31
21
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HReinken
SHeidenreich
MBär
S. H. LKlapp
article
KulawiakLBE2018
Oscillatory motion of a droplet in an active poroelastic two-phase model
Journal of Physics D: Applied Physics
2019
1
1
52
1
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10.1088/1361-6463/aae41d
D AKulawiak
JLöber
MBär
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article
OlbrichSROBS2018
Validation of simulations in multiphase flow metrology by comparison with experimental video observation
J. Phys.: Conf. Series
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11
1
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MOlbrich
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LRiazy
KOberleithner
MBär
SSchmelter
article
SchmelterOSB2018
Validation of multiphase flow simulations by comparison with experimental video observations
Proceedings of the North Sea Flow Measurement Workshop 2018
2018
11
1
8.4,8.41,Flow
SSchmelter
MOlbrich
ESchmeyer
MBär
article
HeidenreichGB2018
Bayesian approach to determine critical dimensions from scatterometric measurements
Metrologia
2018
10
19
55
6
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10.1088/1681-7575/aae41c
SHeidenreich
HGross
MBär
article
LehnertWKCCESSE2018
Pixel-wise quantification of myocardial perfusion using spatial Tikhonov regularization
Physics in Medicine & Biology
2018
10
10
63
215017
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JLehnert
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CKolbitsch
AChiribiri
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GEbrard
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CElster
article
ArielSRHBB2018
Collective dynamics of two-dimensional swimming bacteria: Experiments and models
PHYSICAL REVIEW E
2018
9
24
98
3
032415
8.4,8.43
10.1103/PhysRevE.98.032415
GAriel
MSidortsov
S DRyan
SHeidenreich
MBär
ABe'er
article
WuebbelerBHE2018
Maintaining consensus for the redefined kilogram
Metrologia
2018
9
7
55
5
722
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10.1088/1681-7575/aadb6b
GWübbeler
HBettin
FHärtig
CElster
article
KastnerSHUHKPRWE2018
Compressed sensing FTIR nano-spectroscopy and nano-imaging
Optics Express
2018
7
26
14
18115--18124
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BKästner
FSchmähling
AHornemann
GUlrich
AHoehl
MKruskopf
KPierz
MRaschke
GWübbeler
CElster
article
KhaninARE2018
Assessment of CT image quality using a Bayesian framework
IEEE Transactions on Medical Imaging
2018
6
19
37
12
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AKhanin
MAnton
MReginatto
CElster
article
PossoloBBMW2018
Value assignment and uncertainty evaluation for single-element reference solutions
Metrologia
2018
5
9
55
3
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APossolo
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T AButler
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Local control of globally competing patterns in coupled Swift–Hohenberg equations
Chaos: An Interdisciplinary Journal of Nonlinear Science
2018
4
30
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10.1063/1.5018139
MBecker
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TNiedermayer
SReichelt
AMielke
MBär
article
SchachtschneiderFSABBBBKKLLMPRSSWWSE2018
Interlaboratory comparison measurements of aspheres
Measurement Science and Technology
2018
4
9
29
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RSchachtschneider
IFortmeier
MStavridis
JAsfour
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R BBergmann
ABeutler
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HKlawitter
KKubo
JLiebl
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RMeeß
CPruss
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MSandner
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MWendel
IWiddershoven
MSchulz
CElster
article
AntonKKRE2018
A simple parametric model observer for quality assurance in computer tomography
Physics in Medicine & Biology
2018
3
27
63
7
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10.1088/1361-6560/aab24a
MAnton
AKhanin
TKretz
MReginatto
CElster
article
KlauenbergKKRE2018
Reducing sample size by tightening test conditions
Quality and Reliability Engineering International
2018
2
26
8.4, 8.42, Stichprobenverf
10.1002/qre.2256
KKlauenberg
RKramer
CKroner
JRose
CElster
article
ReinkenKBH2018
Derivation of a hydrodynamic theory for mesoscale dynamics in microswimmer suspensions
Physical Review E 97
2018
2
22
97
2
022613
8.4, 8.43, Active fluids, hydrodynamics theory, microswimmers
10.1103/PhysRevE.97.022613
HReinken
S H LKlapp
MBär
SHeidenreich
article
StrakaFEK2018
Hybrid simulation of a segmental orifice plate
Flow Measurement and Instrumentation
2018
2
14
60
124--133
8.4,8.41,Flow,UQ
10.1016/j.flowmeasinst.2018.02.006
MStraka
AFiebach
TEichler
CKoglin
article
PossoloB2018
Approximate Bayesian evaluations of measurement uncertainty
Metrologia
2018
2
2
55
2
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8.4, 8.42
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APossolo
OBodnar
article
BodnarE2016
Assessment of vague and noninformative priors for Bayesian estimation of the realized random effects in random-effects meta-analysis
AStA Advances in Statistical Analysis
2018
1
31
102
1
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8.42,KC,Unsicherheit
10.1007/s10182-016-0279-7
OBodnar
CElster
article
WubbelerBE2018
Robust Bayesian linear regression with application to an analysis of the CODATA values for the Planck constant
Metrologia
2018
1
2
55
1
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8.4,8.42,Unsicherheit,Regression
10.1088/1681-7575/aa98aa
GWübbeler
OBodnar
CElster
article
DierlEFKEE2018
Novel accuracy test for multispectral imaging systems based on ΔE measurements
Journal of the European Optical Society-Rapid Publications
2018
1
2
14
1
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8.4,8.42
10.1186/s41476-017-0069-1
MDierl
TEckhard
BFrei
MKlammer
SEichstädt
CElster
article
GiengerBN2018
Extinction spectra of suspensions of microspheres: determination of the spectral refractive index and particle size distribution with nanometer accuracy
Applied Optics
2018
1
1
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2
344 -- 355
8.4,8.41,Cyto
10.1364/AO.57.000344
JGienger
MBär
JNeukammer
article
BuranBN2017
Control of electrical turbulence by periodic excitation of cardiac tissue
Chaos
2017
11
19
27
11
113110
8.4,8.43,8.41
10.1063/1.5010787
PBuran
MBär
SAlonso
TNiedermayer
article
AlonsoREB2017
Mechanochemical pattern formation in simple models of active viscoelastic fluids and solids
Journal of Physics D: Applied Physics
2017
10
3
50
43
434004
8.4,8.41
10.1088/1361-6463/aa8a1d
SAlonso
MRadszuweit
HEngel
MBär
article
BarE2018
Mathematics and Statistics for Digitalization
PTB Mitteilungen
2017
10
1
127
4
69--74
8.4,8.41,8.42
https://www.ptb.de/cms/fileadmin/internet/publikationen/ptb_mitteilungen/mitt2017/Heft4/PTB-Mitteilungen_2017_Heft_4.pdf
MBär
CElster
article
SchmahlingWKRSTSE2017
Uncertainty evaluation and propagation for spectral measurements
Color, Research and Application
2017
9
26
43
1
6--16
8.4,8.42,Unsicherheit,LargeScaleDataAna
10.1002/col.22185
FSchmähling
GWübbeler
UKrüger
BRuggaber
FSchmidt
R DTaubert
ASperling
CElster
article
MullerHLNVWWW2017
Verification of calibration methods for determining photon-counting detection efficiency using superconducting nano-wire single photon detectors
Opt. Express
2017
9
1
25
18
21483--21495
8.4,8.42
10.1364/OE.25.021483
IMüller
R DHoransky
J HLehman
S WNam
IVayshenker
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WubbelerE2017
A Large-Scale Optimization Method Using a Sparse Approximation of the Hessian for Magnetic Resonance Fingerprinting
SIAM J. Imaging Sci.
2017
8
21
10
3
979--1004
8.4,8.42,Fingerprinting,LargeScaleDataAna
10.1137/16M1095032
GWübbeler
CElster
article
WeissenbrunnerFJT2017
A coupled numerical and laser optical method for on-site calibration of flow meters
Eccomas Proceedia UNCECOMP
2017
6
17
5393
576--587
8.4,8.41,Flow,UQ
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AWeissenbrunner
AFiebach
MJuling
P UThamsen
article
ReginattoAE2017
Assessment of CT image quality using a Bayesian approach
Metrologia
2017
6
14
54
4
S74--S82
8.4,8.42,Unsicherheit
10.1088/1681-7575/aa735b
MReginatto
MAnton
CElster
article
EichstadtW2017
Evaluation of uncertainty for regularized deconvolution: A case study in hydrophone measurements
J. Acoust. Soc. Am.
2017
6
6
141
6
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8.4,8.42,Unsicherheit,Dynamik
10.1121/1.4983827
SEichstädt
VWilkens
article
BodnarBE2017
Bayesian inference for measurements of ionizing radiation under partial information
Metrologia
2017
5
11
54
3
S29--S33
8.4,8.42,Unsicherheit
10.1088/1681-7575/aa69ad
OBodnar
RBehrens
CElster
article
KobuschE2017
A case study in model-based dynamic calibration of small strain gauge force transducers
Acta IMEKO
2017
4
1
6
1
3--12
Abstract: Investigations of the model-based dynamic calibration of a small strain gauge force transducer of high bandwidth revealed new challenges for parameter identification. This paper discusses a more generalized mechanical model of the calibration set-up employed taking account of the transducer’s connection to its mechanical environment at both ends. Based on new experimental sine and shock force data, the improved model is studied and its parameters are identified. It is shown that the proposed model is capable of linking the calibration results of both calibration methods to a much better degree. This paper is an extended version of the original contribution to the IMEKO 2015 conference in Prague, Czech Republic.
dynamic modelling, parameter identification, sine force calibration, shock force calibration
8.4,8.42,Dynamik
10.21014/acta_imeko.v6i1.433
MKobusch
SEichstädt
article
EichstadtESE2017
Evaluation of dynamic measurement uncertainty – an open-source software package to bridge theory and practice
J. Sens. Sens. Syst.
2017
2
14
6
97-105
8.4,8.42,Unsicherheit,Dynamik
10.5194/jsss-6-97-2017
SEichstädt
CElster
I MSmith
T JEsward
article
GrossHB2016
Impact of different stochastic line edge roughness patterns on measurements in scatterometry - a simulation study
Measurement
2017
2
1
98
339--346
8.4,8.43,Scatter-Inv
10.1016/j.measurement.2016.08.027
HGross
SHeidenreich
MBär
article
HeidenreichGBW2016
Uncertainty propagation in computationally expensive models: A survey of sampling methods and application to scatterometry
Measurement
2017
2
1
97
79--87
8.4,8.43,UQ
10.1016/j.measurement.2016.06.009
SHeidenreich
HGross
MBär
LWright
article
BodnarLAPE2017
Bayesian estimation in random effects meta-analysis using a non-informative prior
Statistics in Medicine
2017
2
1
39
2
378--399
8.4,8.42,KC,Unsicherheit
1097-0258
10.1002/sim.7156
OBodnar
ALink
BArendacká
APossolo
CElster
article
ElsterW2017
Bayesian inference using a noninformative prior for linear Gaussian random coefficient regression with inhomogeneous within-class variances
Comput. Stat.
2017
1
3
32
1
51--69
A Bayesian inference for a linear Gaussian random coefficient regression model with inhomogeneous within-class variances is presented. The model is moti- vated by an application in metrology, but it may well find interest in other fields. We consider the selection of a noninformative prior for the Bayesian inference to address applications where the available prior knowledge is either vague or shall be ignored. The noninformative prior is derived by applying the Berger and Bernardo reference prior principle with the means of the random coefficients forming the parameters of interest. We show that the resulting posterior is proper and specify conditions for the existence of first and second moments of the marginal posterior. Simulation results are presented which suggest good frequentist properties of the proposed inference. The calibration of sonic nozzle data is considered as an application from metrology. The proposed inference is applied to these data and the results are compared to those obtained by alternative approaches.
random coefficient regression, Bayesian inference, noninformative prior
8.42, Regression
10.1007/s00180-015-0641-3
CElster
GWübbeler
article
KlauenbergE2017
Sampling for assurance of future reliability
Metrologia
2017
1
2
54
1
59--68
8.42, Unsicherheit
8.42, Unsicherheit, Stichprobenverf
10.1088/1681-7575/54/1/59
KKlauenberg
CElster
article
WubbelerCE2016
Evaluation of uncertainties for CIELAB color coordinates
Color Research & Application
2016
12
31
8.4,8.42,Unsicherheit
10.1002/col.22109
GWübbeler
JCampos Acosta
CElster
article
BodnarS2016
CUSUM control schemes for monitoring the covariance matrix of multivariate time series
Statistics
2016
12
27
51
4
722--744
8.4,8.42
10.1080/02331888.2016.1268616
OBodnar
WSchmid
article
GiengerGNB2016
Determining the refractive index of humanhemoglobin solutions by Kramers–Kronig relations with an improved absorption model.
Applied Optics
2016
11
25
55
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8951--8961
8.4,8.41,Cyto
10.1364/AO.55.008951
JGienger
HGroß
JNeukammer
MBär
article
AlonsoWB2016
Reentry and Ectopic Pacemakers Emerge in aThree-Dimensional Model for a Slab of Cardiac Tissue with Diffuse Microfibrosis nearthe Percolation Threshold
PLOS One
2016
11
25
11
11
8.4,8.41,8.43
10.1371/journal.pone.0166972
SAlonso
RWeber dos Santos
MBär
article
GrosmannPB2016_2
Mesoscale pattern formation of self-propelled rodswith velocity reversal
Phys. Rev. E
2016
11
25
94
5
050602
8.4,8.43,8.41
10.1103/PhysRevE.94.050602
RGroßmann
FPeruani
MBär
article
WrightTMWBE2016
Transfer standard uncertainty can cause inconclusive inter-laboratory comparisons
Metrologia
2016
10
20
53
6
1243
8.42,8.4,KC
8.42,8.4,KC
10.1088/0026-1394/53/6/1243
JWright
BToman
BMickan
GWübbeler
OBodnar
CElster
article
Eichstaedt2016d
On the evaluation of uncertainties for state estimation with the Kalman filter
Measurement Science and Technology
2016
10
20
27
12
125009
The Kalman ﬁlter is an established tool for the analysis of dynamic systems with normally distributed noise, and it has been successfully applied in numerous areas. It provides sequentially calculated estimates of the system states along with a corresponding covariance matrix. For nonlinear systems, the extended Kalman ﬁlter is often used. This is derived from the Kalman ﬁlter by linearization around the current estimate. A key issue in metrology is the evaluation of the uncertainty associated with the Kalman ﬁlter state estimates. The “Guide to the Expression of Uncertainty in Measurement” (GUM) and its supplements serve as the de facto standard for uncertainty evaluation in metrology. We explore the relationship between the covariance matrix produced by the Kalman ﬁlter and a GUM-compliant uncertainty analysis. In addition, the results of a Bayesian analysis are considered. For the case of linear systems with known system matrices, we show that all three approaches are compatible. When the system matrices are not precisely known, however, or when the system is nonlinear, this equivalence breaks down and diﬀerent results can then be reached. For precisely known nonlinear systems, though, the result of the extended Kalman ﬁlter still corresponds to the linearized uncertainty propagation of the GUM. The extended Kalman ﬁlter can suﬀer from linearization and convergence errors. These disadvantages can be avoided to some extent by applying Monte Carlo procedures, and we propose such a method which is GUM-compliant and can also be applied online during the estimation. We illustrate all procedures in terms of a two-dimensional dynamic system and compare the results with those obtained by particle ﬁltering, which has been proposed for the approximate calculation of a Bayesian solution. Finally, we give some recommendations based on our ﬁndings.
Kalman filter, uncertainty, dynamic measurement, state-space system, state estimation
8.4, 8.42, Dynamik
10.1088/0957-0233/27/12/125009
SEichstädt
NMakarava
CElster
article
FanKVKBSSWBEST2016
Direct measurement of the γ He / γ Xe ratio at ultralow magnetic field
Journal of Physics: Conference Series
2016
10
14
723
1
012045
8.42
10.1088/1742-6596/723/1/012045
IFan
SKnappe-Grünberg
JVoigt
WKilian
MBurghoff
DStollfuss
ASchnabel
GWübbeler
OBodnar
CElster
FSeifert
LTrahms
article
FiebachSKS2016
Numerical simulation of multiphase flow in a vertically mounted Venturi flow meter
Proceedings of the 17th International Flow Measurement Conference FLOMEKO 2016
2016
9
29
8.4,8.41,Flow
AFiebach
ESchmeyer
SKnotek
SSchmelter
article
KnotekFS2016
Numerical simulation of multiphase flows in large horizontal pipes
Proceedings of the 17th International Flow Measurement Conference FLOMEKO 2016
2016
9
29
8.4,8.41,Flow
SKnotek
AFiebach
SSchmelter
article
HeidenreichDKB2016
Hydrodynamic length-scale selection in microswimmer suspensions
Physical Review E
2016
8
29
94
2
020601
8.4,8.43,ActFluid
10.1103/PhysRevE.94.020601
SHeidenreich
JDunkel
H.LKlapp
MBär
article
AlonsoBE2016
Nonlinear physics of electrical wave propagation in the heart: a review
Reports on Progress in Physics
2016
8
29
79
9
096601
8.4,8.41,8.43,Herz
10.1088/0034-4885/79/9/096601
SAlonso
MBär
BEchebarria
article
AlonsoB2016
Reentry produced by small-scale heterogeneities in a discrete model of cardiac tissue
Journal of Physics: Conference Series
2016
8
29
727
1
012002
8.4,8.41,8.43,Herz
10.1088/1742-6596/727/1/012002
SAlonso
MBär
article
WeissenbrunnerFSMTL2016
Simulation-based determination of systematic errors of flow meters due to uncertain inflow conditions
Flow Measurement and Instrumentation
2016
8
29
8.4,8.41,Flow,UQ
in_preparation
10.1016/j.flowmeasinst.2016.07.011
AWeissenbrunner
AFiebach
SSchmelter
MBär
P.UThamsen
TLederer
article
LangovoySW2016
Numerical comparison of sampling strategies for BRDF data manifolds
Measurement
2016
8
12
94
Supplement C
578--584
8.42
8.42
10.1016/j.measurement.2016.08.010
MLangovoy
FSchmähling
GWübbeler
phdthesis
Fortmeier2016
Zur Optimierung von Auswerteverfahren für Tilted-Wave Interferometer
Institut für Technische Optik, Universität Stuttgart
2016
7
31
Berichte aus dem Institut für Technische Optik
82
8.42,Form
8.42,Form
Stuttgart
Institut für Technische Optik, Universität Stuttgart
Berichte aus dem Institut für Technische Optik
10.18419/opus-8878
IFortmeier
article
WubbelerBE2016
Bayesian hypothesis testing for key comparisons
Metrologia
2016
7
18
53
4
1131--1138
8.42,KC
8.42,KC
10.1088/0026-1394/53/4/1131
GWübbeler
OBodnar
CElster
article
DierlEFKEE2016
Improved estimation of reflectance spectra by utilizing prior knowledge
Journal of the Optical Society of America A
2016
6
23
33
7
1370--1376
dynamic measurement, dynamic uncertainty, deconvolution
8.42, Dynamik, Regression
10.1364/JOSAA.33.001370
MDierl
TEckhard
BFrei
MKlammer
SEichstädt
CElster
article
Eichstaedt2016c
On challenges in the uncertainty evaluation for time-dependent measurements
Metrologia
2016
6
53
4
The measurement of quantities with time-dependent values is a common task in many areas of metrology. Although well established techniques are available for the analysis of such measurements, serious scientific challenges remain to be solved to enable their routine use in metrology. In this paper we focus on the challenge of estimating a time-dependent measurand when the relationship between the value of the measurand and the indication is modeled by a convolution. Mathematically, deconvolution is an ill-posed inverse problem, requiring regularization to stabilize the inversion in the presence of noise. We present and discuss deconvolution in three practical applications: thrust-balance, ultra-fast sampling oscilloscopes and hydrophones. Each case study takes a different approach to modeling the convolution process and regularizing its inversion. Critically, all three examples lack the assignment of an uncertainty to the influence of the regularization on the estimation accuracy. This is a grand challenge for dynamic metrology, for which to date no generic solution exists. The case studies presented here cover a wide range of time scales and prior knowledge about the measurand, and they can thus serve as starting points for future developments in metrology. The aim of this work is to present the case studies and demonstrate the challenges they pose for metrology.
dynamic measurement, dynamic uncertainty, deconvolution
8.42, Dynamik
10.1088/0026-1394/53/4/S125
SEichstädt
VWilkens
ADienstfrey
PHale
BHughes
CJarvis
article
GrosmannPB2013
Superdiffusion, large-scale synchronization, and topological defects
Phys. Rev. E
2016
4
31
93
8.43
8.4,8.43,8.41
10.1103/PhysRevE.93.040102
RGroßmann
FPeruani
MBär
article
GrosmannPB2016
Diffusion properties of active particles with directional reversal
New J. Phys
2016
4
31
18
8.43
8.4,8.43,8.41
10.1088/1367-2630/18/4/043009
RGroßmann
FPeruani
MBär
article
Alonso_PhysD_2015
Oscillations and uniaxial mechanochemical waves in a model of an active poroelastic medium: Application to deformation patterns in protoplasmic droplets of Physarum polycephalum
Physica D
2016
4
1
318
58-69
8.41, Spatio-Diff, ActFluid
10.1016/j.physd.2015.09.017
SAlonso
UStrachauer
MRadszuweit
MBär
M.J.BHauser
article
e73c330da32016
GUM2DFT — a software tool for uncertainty evaluation of transient signals in the frequency domain
Measurement Science and Technology
2016
3
22
27
5
055001
The Fourier transform and its counterpart for discrete time signals, the discrete Fourier transform (DFT), are common tools in measurement science and application. Although almost every scientific software package offers ready-to-use implementations of the DFT, the propagation of uncertainties in line with the guide to the expression of uncertainty in measurement (GUM) is typically neglected. This is of particular importance in dynamic metrology, when input estimation is carried out by deconvolution in the frequency domain. To this end, we present the new open-source software tool GUM2DFT , which utilizes closed formulas for the efficient propagation of uncertainties for the application of the DFT, inverse DFT and input estimation in the frequency domain. It handles different frequency domain representations, accounts for autocorrelation and takes advantage of the symmetry inherent in the DFT result for real-valued time domain signals. All tools are presented in terms of examples which form part of the software package. GUM2DFT will foster GUM-compliant evaluation of uncertainty in a DFT-based analysis and enable metrologists to include uncertainty evaluations in their routine work.
dynamic measurements; deconvolution; discrete Fourier transform; uncertainty;
8.42, Dynamik
10.1088/0957-0233/27/5/055001
SEichstädt
VWilkens
article
Schmelter_2016_1
Polynomchaos zur Unsicherheitsquantifizierung in Strömungssimulationen für metrologische Anwendungen
tm-Technisches Messen
2016
1
8
83
2
71-76
8.41, Flow, UQ
http://www.degruyter.com/view/j/teme.2016.83.issue-2/teme-2015-0109/teme-2015-0109.xml
SSchmelter
AFiebach
AWeissenbrunner
article
Fortmeier:16
Evaluation of absolute form measurements using a tilted-wave interferometer
Opt. Express
2016
1
8
24
4
3393--3404
Tilted-wave interferometry is a promising measurement technique for the highly accurate measurement of aspheres and freeform surfaces. However, the interferometric fringe evaluation of the sub-apertures causes unknown patch offsets, which currently prevent this measurement technique from providing absolute measurements. Simple strategies, such as constructing differences of optical path length differences (OPDs) or ignoring the piston parameter, can diminish the accuracy resulting from the absolute form measurement. Additional information is needed instead; in this paper, the required accuracy of such information is explored in virtual experiments. Our simulation study reveals that, when one absolute OPD is known within a range of 500 nm, the accuracy of the final measurement result is significantly enhanced.
Interferometry; Metrology; Surface measurements, figure; Aspherics
8.42,Form,EMRP-Form
http://www.opticsexpress.org/abstract.cfm?URI=oe-24-4-3393
OSA
10.1364/OE.24.003393
IFortmeier
MStavridis
AWiegmann
MSchulz
WOsten
CElster
article
Eichstadt2016
Modellierung dynamischer Messsysteme - von stochastischen Prozessen zu praktikablen Messunsicherheiten
tm - Technisches Messen
2016
1
6
83
2
66-70
Dynamische Messungen spielen eine zunehmend wichtigere Rolle in der metrologischen und industriellen Praxis. Zugleich stellt die Analyse dynamischer Messungen unter Berücksichtigung metrologischer Gesichtspunkte neue Herausforderungen an die mathematische und statistische Modellierung. Dieser Artikel stellt eine Reihe aktueller Modellierungskonzepte zu den einzelnen Aspekten der Messkette einer dynamischen Messungen vor. Es werden Vor- und Nachteile der Modellierungskonzepte diskutiert und Zielstellungen für zukünftige Forschungsarbeiten herausgestellt.
8.42, Dynamik
http://www.degruyter.com/view/j/teme.2016.83.issue-2/teme-2015-0098/teme-2015-0098.xml?format=INT
0171-8096
10.1515/teme-2015-0098
SEichstädt
CElster
article
Lindner_JFE2015
A Computational Fluid Dynamics Study on the Gas Mixing Capabilities of a Multiple Inlet System
J. Fluids Eng
2016
1
5
138
3
031302
8.41, Flow
8.41, Flow
10.1115/1.4031380
GLindner
SSchmelter
RModel
ANowak
VEbert
MBär
article
Bodnar2016b
Evaluation of uncertainty in the adjustment of fundamental constants
Metrologia
2016
1
5
53
1
S46
Combining multiple measurement results for the same quantity is an important task in metrology and in many other areas. Examples include the determination of fundamental constants, the calculation of reference values in interlaboratory comparisons, or the meta-analysis of clinical studies. However, neither the GUM nor its supplements give any guidance for this task. Various approaches are applied such as weighted least-squares in conjunction with the Birge ratio or random effects models. While the former approach, which is based on a location-scale model, is particularly popular in metrology, the latter represents a standard tool used in statistics for meta-analysis. We investigate the reliability and robustness of the location-scale model and the random effects model with particular focus on resulting coverage or credible intervals. The interval estimates are obtained by adopting a Bayesian point of view in conjunction with a non-informative prior that is determined by a currently favored principle for selecting non-informative priors. Both approaches are compared by applying them to simulated data as well as to data for the Planck constant and the Newtonian constant of gravitation. Our results suggest that the proposed Bayesian inference based on the random effects model is more reliable and less sensitive to model misspecifications than the approach based on the location-scale model.
8.42, Unsicherheit
http://stacks.iop.org/0026-1394/53/i=1/a=S46
10.1088/0026-1394/53/1/S46
OBodnar
CElster
JFischer
APossolo
BToman
article
Klauenberg2016
Markov chain Monte Carlo methods: an introductory example
Metrologia
2016
1
3
53
1
S32
When the Guide to the Expression of Uncertainty in Measurement (GUM) and methods from its supplements are not applicable, the Bayesian approach may be a valid and welcome alternative. Evaluating the posterior distribution, estimates or uncertainties involved in Bayesian inferences often requires numerical methods to avoid high-dimensional integrations. Markov chain Monte Carlo (MCMC) sampling is such a method---powerful, flexible and widely applied. Here, a concise introduction is given, illustrated by a simple, typical example from metrology. The Metropolis--Hastings algorithm is the most basic and yet flexible MCMC method. Its underlying concepts are explained and the algorithm is given step by step. The few lines of software code required for its implementation invite interested readers to get started. Diagnostics to evaluate the performance and common algorithmic choices are illustrated to calibrate the Metropolis--Hastings algorithm for efficiency. Routine application of MCMC algorithms may be hindered currently by the difficulty to assess the convergence of MCMC output and thus to assure the validity of results. An example points to the importance of convergence and initiates discussion about advantages as well as areas of research. Available software tools are mentioned throughout.
Bayesian, MCMC, Markov chain Monte Carlo
8.42, Unsicherheit, Regression
http://stacks.iop.org/0026-1394/53/i=1/a=S32
10.1088/0026-1394/53/1/S32
KKlauenberg
CElster
article
Elster2016a
Bayesian regression versus application of least squares—an example
Metrologia
2016
1
2
53
1
S10
Regression is an important task in metrology and least-squares methods are often applied in this context. Bayesian inference provides an alternative that can take into account available prior knowledge. We illustrate similarities and differences of the two approaches in terms of a particular nonlinear regression problem. The impact of prior knowledge utilized in the Bayesian regression depends on the amount of information contained in the data, and by considering data sets with different signal-to-noise ratios the relevance of the employed prior knowledge for the results is investigated. In addition, properties of the two approaches are explored in the context of the particular example.
8.4, 8.42, Unsicherheit, Regression
http://stacks.iop.org/0026-1394/53/i=1/a=S10
10.1088/0026-1394/53/1/S10
CElster
GWübbeler
article
Bodnar2015
Objective Bayesian Inference for a Generalized Marginal Random Effects Model
Bayesian Analysis
2016
1
1
11
1
25-45
Open Access
objective Bayesian inference,random effects model,reference prior
8.42, Unsicherheit
http://projecteuclid.org/euclid.ba/1423083638
International Society for Bayesian Analysis
1931-6690
10.1214/14-BA933
OBodnar
ALink
CElster
article
e73c330da32016_3
Reconstructing interaction potentials in thin films from real-space images
Phys. Rev. E
2016
93
4
043306
8.4,8.41
10.1103/PhysRevE.93.043306
JGienger
NSeverin
JRabe
I MSokolov
article
SH
Generalized Swift-Hohenberg models for dense active suspensions
Eur. Phys. J. E
2016
39
10
97
8.4,8.43,ActFluid
10.1140/epje/i2016-16097-2
AUOza
SHeidenreich
JDunkel
article
e73c330da32016_2
Numerical prediction of the flow rate through a flow meter with uncertain inflow profile
Proceedings of Imeko 2015 XXI World Congress Measurement in Research and Industry
2015
11
30
8.41, Flow, UQ
AWeissenbrunner
AFiebach
SSchmelter
MStraka
MBär
TLederer
article
Grossmann_EPJ2015_2
A geometric approach to self-propelled motion in isotropic & anisotropic environments
Eur. Phys. J - Special Topics
2015
1
9
224
7
1377-1394
8.41, ActMatter
10.1140/epjst/e2015-02465-0
RGroßmann
FPeruani
MBär
article
heidenreich2015bayesian
Bayesian approach to the statistical inverse problem of scatterometry: Comparison of three surrogate models
International Journal for Uncertainty Quantification
2015
1
8
511
8.43, Scatter-Inv, UQ
10.1615/Int.J.UncertaintyQuantification.2015013050
SHeidenreich
HGross
MBär
article
Bunk
CCQM-P58.1: Immunoassay Quantitation of Human Cardiac Troponin I.
Metrologia
2015
1
8
52
1A
08006
The CCQM study P58.1 assessed the equivalence of immunoassay measurements between participating NMIs. The aim of P58.1 was to demonstrate the equivalence of immunoassay measurements to determine the mass concentration of the clinically-relevant protein human cardiac troponin I (cTnI) present at low concentration relative to the protein concentration of the sample matrix. The measurement equivalence was assessed using traceability to a common certified reference material. To quantify cTnI, participants used a homogeneous sandwich-based immunoassay with an enzymatic amplification step. The antibody format consisted of a single capture and single detection antibody (referred to as 1 + 1), both were supplied to study participants. In the previous P58 study, ELISA measurement results were compared between laboratories which all used common ELISA reagents (including 96-well plates), samples, a standard for the production of calibrants, and a detailed ELISA protocol, which were supplied by a single laboratory. The P58.1 study only utilized common samples, a standard of the production of calibrants, and a set of monoclonal antibodies (mAbs). Because much of the experimental procedure for the P58 study was essentially standardized across participating labs, the study primarily highlighted between-laboratory differences in plate sampling designs and in plate reader response. As the participants in the P58.1 study had to produce most of their own analytical reagents and develop their own measurement procedure, the study provides a better evaluation of the equivalence of ELISA measurements between the participating laboratories. Main text. To reach the main text of this paper, click on Final Report [http://www.bipm.org/utils/common/pdf/final_reports/QM/P58/CCQM-P58.1.pdf] The final report has been peer-reviewed and approved for publication by CCQM.
8.42,ELISA
http://stacks.iop.org/0026-1394/52/i=1A/a=08006
10.1088/0026-1394/52/1A/08006
DBunk
JNoble
A EKnight
LWang
KKlauenberg
MWalzel
CElster
article
Radszu_PRE2015
Cardiac contraction induces discordant alternans and localized block
Phys. Rev. E
2015
1
7
91
022703
8.41, Herz
10.1103/PhysRevE.91.022703
MRadszuweit
EAlvarez-Lacalle
MBär
BEchebarria
article
Klauenberg2015_3
A tutorial on Bayesian Normal linear regression
Metrologia
2015
1
7
52
6
878--892
Regression is a common task in metrology and often applied to calibrate instruments, evaluate inter-laboratory comparisons or determine fundamental constants, for example. Yet, a regression model cannot be uniquely formulated as a measurement function, and consequently the Guide to the Expression of Uncertainty in Measurement (GUM) and its supplements are not applicable directly. Bayesian inference, however, is well suited to regression tasks, and has the advantage of accounting for additional a priori information, which typically robustifies analyses. Furthermore, it is anticipated that future revisions of the GUM shall also embrace the Bayesian view.Guidance on Bayesian inference for regression tasks is largely lacking in metrology. For linear regression models with Gaussian measurement errors this tutorial gives explicit guidance. Divided into three steps, the tutorial first illustrates how a priori knowledge, which is available from previous experiments, can be translated into prior distributions from a specific class. These prior distributions have the advantage of yielding analytical, closed form results, thus avoiding the need to apply numerical methods such as Markov Chain Monte Carlo. Secondly, formulas for the posterior results are given, explained and illustrated, and software implementations are provided. In the third step, Bayesian tools are used to assess the assumptions behind the suggested approach.These three steps (prior elicitation, posterior calculation, and robustness to prior uncertainty and model adequacy) are critical to Bayesian inference. The general guidance given here for Normal linear regression tasks is accompanied by a simple, but real-world, metrological example. The calibration of a flow device serves as a running example and illustrates the three steps. It is shown that prior knowledge from previous calibrations of the same sonic nozzle enables robust predictions even for extrapolations.
8.42, Regression, Unsicherheit
10.1088/0026-1394/52/6/878
KKlauenberg
GWübbeler
BMickan
PHarris
CElster
article
Bosse_TM2015
Challenges in nanometrology: high precision measurement of position and size
Technisches Messen
2015
1
6
82
346-358
8.41, Scatter-Inv
10.1515/teme-2015-0002
HBosse
BBodermann
GDai
JFlügge
C. GFrase
HGross
WHäßler-Grohne
PKöchert
RKönning
FScholze
CWeichert
article
Schmelt_JCF2015
Numerical prediction of the influence of uncertain inflow conditions in pipes by polynomial chaos
Int. J. Comp. Fluid. Dyn.
2015
1
5
29
6-8
411-422
8.41, Flow, UQ
10.1080/10618562.2015.1112899
SSchmelter
AFiebach
RModel
MBär
article
Kobusch2015
Investigations for the model-based dynamic calibration of force transducers by using shock excitation
ACTA IMEKO
2015
1
5
4
2
45-51
Within the scope of the joint research project EMRP IND09 “Traceable dynamic measurements of mechanical quantities”, numerous measurements were performed at PTB’s 20 kN primary shock force calibration device to investigate and validate the approach of a model-based dynamic calibration of force transducers by using shock excitations. The tests included several strain gauge force transducers of greatly differing structural design, size, weight and mechanical coupling. By looking at a few examples, some investigated physical models of the measurement set-up and a developed data analysis procedure for parameter identification based on measured shock data are presented and discussed. The models reproduce the dynamic response including the observed modal oscillations of various origins that limit the usable measurement bandwidth. Moreover, these modal oscillations may have an important role for the parameter identification process, which is further discussed. This paper is an extended version of the original contribution to the IMEKO 2014 conference in Cape Town, South Africa.
Open Access
model-based dynamic calibration, dynamic calibration, dynamic modelling,editor,force transducers, imeko
8.42, Dynamik
fileadmin/internet/fachabteilungen/abteilung_8/8.4_mathematische_modellierung/Publikationen_8.4/ACTA_IMEKO_2014_Kobusch_et_al_preprint.pdf
http://acta.imeko.org/index.php/acta-imeko/article/view/IMEKO-ACTA-04%20%282015%29-02-08/384
MKobusch
SEichstädt
LKlaus
TBruns
article
Grossmann_EPJE2015
Pattern formation in active particle systems due to competing alignment interactions
Eur. Phys. J - Special Topics
2015
1
4
224
7
1325-1347
8.41,ActMatter,8.43
10.1140/epjst/e2015-02462-3
RGroßmann
PRomanczuk
MBär
LSchimansky-Geier
article
Klaus2014a
Dynamic torque calibration by means of model parameter identification
ACTA IMEKO
2015
1
4
3
1
1-6
For the dynamic calibration of torque transducers, a model of the unmounted transducer and an extended model of the mounted transducer including the measuring device have been developed. The dynamic behaviour of a torque transducer under test will be described by its model parameters. This paper presents the models comprising the known parameters of the measuring device andthe unknown parameters of the transducer and how the calibration measurements are going to be carried out. The principle for the identification of the transducer’s model parameters from measurement data is described using a least squares approach. The influence of a variation of the transducer’s parameters on the frequency response of the expanded model is analysed.
Open Access
mechanical model,model parameter identification
8.42, Dynamik
http://acta.imeko.org/index.php/acta-imeko/article/view/IMEKO-ACTA-04%20%282015%29-02-07/385
LKlaus
BArendacká
MKobusch
TBruns
article
Wubbeler2015
Explanatory power of degrees of equivalence in the presence of a random instability of the common measurand
Metrologia
2015
1
3
52
2
400--405
8.42, Unsicherheit, KC
http://iopscience.iop.org/article/10.1088/0026-1394/52/2/400
IOP Publishing
en
0026-1394
10.1088/0026-1394/52/2/400
GWübbeler
OBodnar
BMickan
CElster
article
Gross2015
Modeling aspects to improve the solution of the inverse problem in scatterometry
Cont. Dyn. S. - S
2015
1
3
8
497-519
8.43,Scatter-Inv
10.3934/dcdss.2015.8.497
HGroß
SHeidenreich
M-AHenn
MBär
ARathsfeld
article
Kok2015
Bayesian analysis of a flow meter calibration problem
Metrologia
2015
1
2
52
2
392-399
Regression, 8.42, Unsicherheit
http://iopscience.iop.org/article/10.1088/0026-1394/52/2/392
IOP Publishing
0026-1394
10.1088/0026-1394/52/2/392
G J PKok
A M Hvan der Veen
P MHarris
I MSmith
CElster
article
NiedermayerL2015
Association-dissociation process with aging subunits: Recursive solution
Phys. Rev. E
2015
1
1
92
5
8.43
8.43
10.1103/PhysRevE.92.052137
TNiedermayer
RLipowsky
article
Klauenberg2015
Informative prior distributions for ELISA analyses
Biostatistics
2015
1
1
16
3
454--64
Immunoassays are capable of measuring very small concentrations of substances in solutions and have an immense range of application. Enzyme-linked immunosorbent assay (ELISA) tests in particular can detect the presence of an infection, of drugs, or hormones (as in the home pregnancy test). Inference of an unknown concentration via ELISA usually involves a non-linear heteroscedastic regression and subsequent prediction, which can be carried out in a Bayesian framework. For such a Bayesian inference, we are developing informative prior distributions based on extensive historical ELISA tests as well as theoretical considerations. One consideration regards the quality of the immunoassay leading to two practical requirements for the applicability of the priors. Simulations show that the additional prior information can lead to inferences which are robust to reasonable perturbations of the model and changes in the design of the data. On real data, the applicability is demonstrated across different laboratories, for different analytes and laboratory equipment as well as for previous and current ELISAs with sigmoid regression function. Consistency checks on real data (similar to cross-validation) underpin the adequacy of the suggested priors. Altogether, the new priors may improve concentration estimation for ELISAs that fulfill certain design conditions, by extending the range of the analyses, decreasing the uncertainty, or giving more robust estimates. Future use of these priors is straightforward because explicit, closed-form expressions are provided. This work encourages development and application of informative, yet general, prior distributions for other types of immunoassays.
Regression, 8.42, ELISA
http://biostatistics.oxfordjournals.org/content/16/3/454
1468-4357
10.1093/biostatistics/kxu057
KKlauenberg
MWalzel
BEbert
CElster
article
Siebert_PRE2014
Dynamics of reation-diffusion patterns controlled by asymmetric nonlocal coupling as a limiting case of differential advection
Phys. Rev. E
2014
89
052909
8.41, RD
10.1103/PhysRevE.89.052909
JSiebert
SAlonso
MBär
ESchöll
article
Meyer2014
Active Brownian agents with concentration-dependent chemotactic sensitivity
Phys. Rev. E
2014
89
2
022711
We study a biologically motivated model of overdamped, autochemotactic Brownian agents with concentration-dependent chemotactic sensitivity. The agents in our model move stochastically and produce a chemical ligand at their current position. The ligand concentration obeys a reaction-diffusion equation and acts as a chemoattractant for the agents, which bias their motion towards higher concentrations of the dynamically altered chemical field. We explore the impact of concentration-dependent response to chemoattractant gradients on large-scale pattern formation, by deriving a coarse-grained macroscopic description of the individual-based model, and compare the conditions for emergence of inhomogeneous solutions for different variants of the chemotactic sensitivity. We focus primarily on the so-called receptor-law sensitivity, which models a nonlinear decrease of chemotactic sensitivity with increasing ligand concentration. Our results reveal qualitative differences between the receptor law, the constant chemotactic response, and the so-called log law, with respect to stability of the homogeneous solution, as well as the emergence of different patterns (labyrinthine structures, clusters, and bubbles) via spinodal decomposition or nucleation. We discuss two limiting cases, where the model can be reduced to the dynamics of single species: (I) the agent density governed by a density-dependent effective diffusion coefficient and (II) the ligand field with an effective bistable, time-dependent reaction rate. In the end, we turn to single clusters of agents, studying domain growth and determining mean characteristics of the stationary inhomogeneous state. Analytical results are confirmed and extended by large-scale GPU simulations of the individual based model.
,Biological,Biomimetic Materials,Biomimetic Materials: chemistry,Biomimetic Materials: metabolism,Chemical,Chemotaxis,Chemotaxis: drug effects,Chemotaxis: physiology,Computer Simulation,Diffusion,Dose-Response Relationship,Drug,Escherichia coli,Escherichia coli: physiology,Models,Statistical,non-linear dynamics
8.41, SPP
http://www.ncbi.nlm.nih.gov/pubmed/25353513
1550-2376
10.1103/PhysRevE.89.022711
MMeyer
LSchimansky-Geier
PRomanczuk
article
Possolo2014
Evaluating the uncertainty of input quantities in measurement models
Metrologia
2014
51
3
339--353
8.42,Unsicherheit
http://iopscience.iop.org/article/10.1088/0026-1394/51/3/339
IOP Publishing
en
0026-1394
10.1088/0026-1394/51/3/339
APossolo
CElster
article
Matthews2014e
Mathematical modelling to support traceable dynamic calibration of pressure sensors
Metrologia
2014
51
3
326-338
dynamic measurement, pressure, parametric model
8.42, Dynamik, Regression
fileadmin/internet/fachabteilungen/abteilung_8/8.4_mathematische_modellierung/Publikationen_8.4/Mathematical_Modelling_Dynamic_Pressure_preprint.pdf
http://iopscience.iop.org/article/10.1088/0026-1394/51/3/326
IOP Publishing
en
doi:10.1088/0026-1394/51/3/326
0026-1394
10.1088/0026-1394/51/3/326
CMatthews
FPennecchi
SEichstädt
AMalengo
TEsward
I MSmith
CElster
AKnott
FArrhén
ALakka
article
Wendt2014
Untersuchungen zum Temperaturverhalten von Flüssigkeiten in großen Lagertanks
Technische Sicherheit
2014
11
13--17
8.41
8.41, Flow
GWendt
RJost
SSchmelter
DWerner
article
Eichstaedt2014
Evaluation of measurement uncertainties for time-dependent quantities
EPJ Web of Conferences
2014
77
3
One of the main challenges in the analysis of dynamic measurements is the estimation of the time-dependent value of the measurand and the corresponding propagation of uncertainties. In this paper we outline the design of appropriate digital compensation filters as a means of estimating the quantity of interest. For the propagation of uncertainty in the application of such digital filters we present online formulae for finite impulse response and infinite impulse response filters. We also demonstrate a recently developed efficient Monte Carlo method for uncertainty propagation in dynamic measurements which allows calculating point-wise coverage intervals in real-time.
8.42, Dynamik
fileadmin/internet/fachabteilungen/abteilung_8/8.4_mathematische_modellierung/Publikationen_8.4/epjconf_icm2014_00003.pdf
EPJ Web of Conferences
10.1051/epjconf/20147700003
SEichstädt
BArendacká
ALink
CElster
article
Spinelli2014
Determination of reference values for optical properties of liquid phantoms based on Intralipid and India ink
Biomedical optics express
2014
5
7
2037--53
A multi-center study has been set up to accurately characterize the optical properties of diffusive liquid phantoms based on Intralipid and India ink at near-infrared (NIR) wavelengths. Nine research laboratories from six countries adopting different measurement techniques, instrumental set-ups, and data analysis methods determined at their best the optical properties and relative uncertainties of diffusive dilutions prepared with common samples of the two compounds. By exploiting a suitable statistical model, comprehensive reference values at three NIR wavelengths for the intrinsic absorption coefficient of India ink and the intrinsic reduced scattering coefficient of Intralipid-20<prt>%</prt> were determined with an uncertainty of about 2<prt>%</prt> or better, depending on the wavelength considered, and 1<prt>%</prt>, respectively. Even if in this study we focused on particular batches of India ink and Intralipid, the reference values determined here represent a solid and useful starting point for preparing diffusive liquid phantoms with accurately defined optical properties. Furthermore, due to the ready availability, low cost, long-term stability and batch-to-batch reproducibility of these compounds, they provide a unique fundamental tool for the calibration and performance assessment of diffuse optical spectroscopy instrumentation intended to be used in laboratory or clinical environment. Finally, the collaborative work presented here demonstrates that the accuracy level attained in this work for optical properties of diffusive phantoms is reliable.
Medical optics instrumentation,Photon migration,Turbid media
8.42,KC
http://www.osapublishing.org/viewmedia.cfm?uri=boe-5-7-2037<prt>&</prt>seq=0<prt>&</prt>html=true
Optical Society of America
EN
2156-7085
10.1364/BOE.5.002037
LSpinelli
MBotwicz
NZolek
MKacprzak
DMilej
PSawosz
ALiebert
UWeigel
TDurduran
FFoschum
AKienle
FBaribeau
SLeclair
J-PBouchard
INoiseux
PGallant
OMermut
AFarina
APifferi
ATorricelli
RCubeddu
H-CHo
MMazurenka
HWabnitz
KKlauenberg
OBodnar
CElster
MBénazech-Lavoué
YBérubé-Lauzière
FLesage
DKhoptyar
A ASubash
SAndersson-Engels
PDi Ninni
FMartelli
GZaccanti
article
Schmahling2014
Virtual experiment for near-field goniophotometric measurements
Applied optics
2014
53
7
1481--7
Near-field goniometric measurements are employed to determine the photometric characteristics of light sources, i.e., the spatial and angular distribution of the emitted light. To this end, a complex measurement system consisting of a goniometer and a CCD-based imaging photometer is employed. In order to gain insight into the measurement system and to enable characterization of the whole measurement setup, we propose to apply a computer model to conduct virtual experiments. Within the computer model, the current state of all parts of the virtual experiment can be easily controlled. The reliability of the computer model is demonstrated by a comparison to actual measurement results. As an example for the application of the virtual experiment, we present an analysis of the impact of axial malpositions of the goniometer and camera.
Gonio,Light-emitting diodes,Mathematical methods (general),Metrological instrumentation,Metrology,Photometry,virtual experiment
8.4,8.42,Form
http://www.osapublishing.org/viewmedia.cfm?uri=ao-53-7-1481<prt>&</prt>seq=0<prt>&</prt>html=true
Optical Society of America
EN
1539-4522
10.1364/AO.53.001481
FSchmähling
GWübbeler
MLopez
FGassmann
UKrüger
FSchmidt
ASperling
CElster
article
Schuler2014
Spatio-temporal dynamics induced by competing instabilities in two asymmetrically coupled nonlinear evolution equations
Chaos
2014
24
4
043142
Pattern formation often occurs in spatially extended physical, biological, and chemical systems due to an instability of the homogeneous steady state. The type of the instability usually prescribes the resulting spatio-temporal patterns and their characteristic length scales. However, patterns resulting from the simultaneous occurrence of instabilities cannot be expected to be simple superposition of the patterns associated with the considered instabilities. To address this issue, we design two simple models composed by two asymmetrically coupled equations of non-conserved (Swift-Hohenberg equations) or conserved (Cahn-Hilliard equations) order parameters with different characteristic wave lengths. The patterns arising in these systems range from coexisting static patterns of different wavelengths to traveling waves. A linear stability analysis allows to derive a two parameter phase diagram for the studied models, in particular, revealing for the Swift-Hohenberg equations, a co-dimension two bifurcation point of Turing and wave instability and a region of coexistence of stationary and traveling patterns. The nonlinear dynamics of the coupled evolution equations is investigated by performing accurate numerical simulations. These reveal more complex patterns, ranging from traveling waves with embedded Turing patterns domains to spatio-temporal chaos, and a wide hysteretic region, where waves or Turing patterns coexist. For the coupled Cahn-Hilliard equations the presence of a weak coupling is sufficient to arrest the coarsening process and to lead to the emergence of purely periodic patterns. The final states are characterized by domains with a characteristic length, which diverges logarithmically with the coupling amplitude.
Computer Simulation,Feedback,Models, Theoretical,Nonlinear Dynamics,Oscillometry,Oscillometry: methods,Spatio-Temporal Analysis,non-linear dynamics,spatio-temporal
8.41, RD, 8.43
http://scitation.aip.org/content/aip/journal/chaos/24/4/10.1063/1.4905017
AIP Publishing
1089-7682
10.1063/1.4905017
DSchüler
S.Alonso
ATorcini
MBär
article
Radszuweit2014
An active poroelastic model for mechanochemical patterns in protoplasmic droplets of Physarum polycephalum
PloS one
2014
9
6
e99220
Motivated by recent experimental studies, we derive and analyze a two-dimensional model for the contraction patterns observed in protoplasmic droplets of Physarum polycephalum. The model couples a description of an active poroelastic two-phase medium with equations describing the spatiotemporal dynamics of the intracellular free calcium concentration. The poroelastic medium is assumed to consist of an active viscoelastic solid representing the cytoskeleton and a viscous fluid describing the cytosol. The equations for the poroelastic medium are obtained from continuum force balance and include the relevant mechanical fields and an incompressibility condition for the two-phase medium. The reaction-diffusion equations for the calcium dynamics in the protoplasm of Physarum are extended by advective transport due to the flow of the cytosol generated by mechanical stress. Moreover, we assume that the active tension in the solid cytoskeleton is regulated by the calcium concentration in the fluid phase at the same location, which introduces a mechanochemical coupling. A linear stability analysis of the homogeneous state without deformation and cytosolic flows exhibits an oscillatory Turing instability for a large enough mechanochemical coupling strength. Numerical simulations of the model equations reproduce a large variety of wave patterns, including traveling and standing waves, turbulent patterns, rotating spirals and antiphase oscillations in line with experimental observations of contraction patterns in the protoplasmic droplets.
,Biological,Biomechanical Phenomena,Calcium,Calcium: metabolism,Cytoplasm,Cytoplasm: physiology,Cytoskeleton,Cytoskeleton: physiology,Elasticity,Mechanical,Models,Physarum polycephalum,Physarum polycephalum: cytology,Physarum polycephalum: physiology,Stress,pattern formation
8.41, ActMatter, ActFluid
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0099220
Public Library of Science
1932-6203
10.1371/journal.pone.0099220
MRadszuweit
HEngel
MBär
article
Bodnar2014a
Analytical derivation of the reference prior by sequential maximization of Shannon's mutual information in the multi-group parameter case
Journal of Statistical Planning and Inference
2014
147
106--116
We provide an analytical derivation of a non-informative prior by sequential maximization of Shannon's mutual information in the multi-group parameter case assuming reasonable regularity conditions. We show that the derived prior coincides with the reference prior proposed by Berger and Bernardo, and that it can be considered as a useful alternative expression for the calculation of the reference prior. In using this expression we discuss the conditions under which an improper reference prior can be uniquely defined, i.e. when it does not depend on the particular choice of nested sequences of compact subsets of the parameter space needed for its construction. We also present the conditions under which the reference prior coincides with Jeffreys' prior.
Bayes,Reference prior,Shannon's mutual information,statistics
8.42, Unsicherheit
http://www.sciencedirect.com/science/article/pii/S0378375813002802
03783758
10.1016/j.jspi.2013.11.003
OBodnar
CElster
article
Bodnar2014
On the adjustment of inconsistent data using the Birge ratio
Metrologia
2014
51
5
516--521
8.42,KC,Regression, Unsicherheit
http://iopscience.iop.org/article/10.1088/0026-1394/51/5/516
IOP Publishing
en
doi:10.1088/0026-1394/51/5/516
0026-1394
10.1088/0026-1394/51/5/516
OBodnar
CElster
article
Eichstadt2014a
Reliable uncertainty evaluation for ODE parameter estimation - a comparison
Journal of Physics: Conference Series
2014
490
1
012230
Regression, ODE, parameter identification, dynamic calibration, modelling
8.42,Dynamik, Regression
http://iopscience.iop.org/article/10.1088/1742-6596/490/1/012230
IOP Publishing
en
1742-6596
10.1088/1742-6596/490/1/012230
SEichstädt
CElster
article
Dai2014
Measurements of CD and sidewall profile of EUV photomask structures using CD-AFM and tilting-AFM
Meas. Sci. Tech.
2014
25
4
044002
Scatterometrie
8.41,Scatter-EUV
http://iopscience.iop.org/article/10.1088/0957-0233/25/4/044002
IOP Publishing
en
0957-0233
10.1088/0957-0233/25/4/044002
GDai
KHahm
FScholze
M-AHenn
HGroß
JFluegge
HBosse
article
Alonso2014
Modeling domain formation of MARCKS and protein kinase C at cellular membranes
Eur. Phys. J. E
2014
2
1
1
pattern formation
8.41, membrane
http://link.springer.com/10.1140/epjnbp14
2195-0008
10.1140/epjnbp14
SAlonso
MBär
article
Arendacka2014c
Independent Quadratic Forms in 3-Variance-Component Models
Communications in Statistics - Theory and Methods
2014
43
5
975-988
This article addresses derivation and existence of quadratic forms that were suggested by Burch (2007) for procedures for inference on variance components in mixed linear models in combination with generalized fiducial inference. A relatively simple algorithm leading to the required quadratic forms in a general 3-variance-component model is stated and designs for two-way ANOVA models without interactions that permit Burch's procedure are characterized. This complements developments in the original article by Burch.
Independent quadratic forms,Random effects,Two-way ANOVA without interactions,Variance components,statistics
8.42
http://www.tandfonline.com/doi/abs/10.1080/03610926.2013.841925?journalCode=lsta20
Taylor <prt>&</prt> Francis Group
en
10.1080/03610926.2013.841925
10.1080/03610926.2013.841925
BArendacká
article
Arendacka2014b
Further remarks on the connection between fixed linear model and mixed linear model
Statistical Papers
2014
56
4
1235--1247
8.42,mixed linear model,statistics
http://link.springer.com/10.1007/s00362-014-0634-2
0932-5026
10.1007/s00362-014-0634-2
BArendacká
SPuntanen
article
Arendacka2014a
Linear Mixed Models: Gum and Beyond
Measurement Science Review
2014
14
2
52-61
In Annex H.5, the Guide to the Evaluation of Uncertainty in Measurement (GUM) [1] recognizes the necessity to analyze certain types of experiments by applying random effects ANOVA models. These belong to the more general family of linear mixed models that we focus on in the current paper. Extending the short introduction provided by the GUM, our aim is to show that the more general, linear mixed models cover a wider range of situations occurring in practice and can be beneﬁcial when employed in data analysis of long-term repeated experiments. Namely, we point out their potential as an aid in establishing an uncertainty budget and as means for gaining more insight into the measurement process. We also comment on computational issues and to make the explanations less abstract, we illustrate all the concepts with the help of a measurement campaign conducted in order to challenge the uncertainty budget in calibration of accelerometers.
dynamic measurement, acceleration, dynamic calibration, mixed model, design of experiment
8.42, Dynamik, Unsicherheit
fileadmin/internet/fachabteilungen/abteilung_8/8.4_mathematische_modellierung/Publikationen_8.4/epjconf_icm2014_00003.pdf
http://www.degruyter.com/view/j/msr.2014.14.issue-2/msr-2014-0009/msr-2014-0009.xml
1335-8871
10.2478/msr-2014-0009
BArendacká
ATäubner
SEichstädt
TBruns
CElster
article
Grossmann2014
Vortex arrays and mesoscale turbulence of self-propelled particles
Phys. Rev. Lett.
2014
113
25
258104
Inspired by the Turing mechanism for pattern formation, we propose a simple self-propelled particle model with short-range alignment and antialignment at larger distances. It is able to produce orientationally ordered states, periodic vortex patterns, and mesoscale turbulence, which resembles observations in dense suspensions of swimming bacteria. The model allows a systematic derivation and analysis of a kinetic theory as well as hydrodynamic equations for density and momentum fields. A phase diagram with regions of pattern formation as well as orientational order is obtained from a linear stability analysis of these continuum equations. Microscopic Langevin simulations of self-propelled particles are in agreement with these findings.
pattern formation,turbulence
8.41,ActMatt,8.43
http://www.ncbi.nlm.nih.gov/pubmed/25554911
1079-7114
10.1103/PhysRevLett.113.258104
RGroßmann
PRomanczuk
MBär
LSchimansky-Geier
article
Haslett2014
The link between the mixed and fixed linear models revisited
Statistical Papers
2014
56
3
849--861
mixed linear models,statistics
8.42, Unsicherheit
http://link.springer.com/10.1007/s00362-014-0611-9
0932-5026
10.1007/s00362-014-0611-9
S JHaslett
SPuntanen
BArendacká
article
Heidenreich2014a
A surrogate model enables a Bayesian approach to the inverse problem of scatterometry
J. Phys. Conf. Ser.
2014
490
1
012007
8.43,Bayes,Scatter-Inv,Regression,8.42, UQ
http://iopscience.iop.org/article/10.1088/1742-6596/490/1/012007
IOP Publishing
en
1742-6596
10.1088/1742-6596/490/1/012007
SHeidenreich
HGross
M-AHenn
CElster
MBär
article
John2014
Traveling waves and global oscillations triggered by attractive molecular interactions in an excitable system
Phys. Rev. E
2014
90
5-1
052913
During pattern formation in spatially extended systems, different mechanisms with different characteristic length scales, e.g., reaction-diffusion processes or molecular interactions, can be active. Such multiscale effects may generate new phenomena, which are not observed in systems where pattern formation occurs on a single scale. Here, we derive and analyze a reaction-diffusion model of the FitzHugh-Nagumo type with short-range attractive molecular interactions of the activator species. The model exhibits a wave instability. Simulations in one and two dimensions show traveling waves with a wavelength set by the parameters of the molecular interaction in the model. In two dimensions, simulations reveal a labyrinthine arrangement of the waves in systems with isotropic diffusion, whereas parallel bands of counterpropagating waves are formed in simulations of a model with anisotropic diffusion. The latter findings are in good qualitative agreement with experimental observation in the catalytic NO+H<prt>\_</prt>{{}2<prt>}</prt> reaction on an anisotropic Rh(110) surface. In addition we have identified a transition regime in the simulations, where a short scale instability triggers global oscillations in an excitable regime.
pattern formation
8.41, exc-media
http://www.ncbi.nlm.nih.gov/pubmed/25493864
1550-2376
10.1103/PhysRevE.90.052913
KJohn
S.Alonso
MBär
article
Henn2014
Improved reconstruction of critical dimensions in extreme ultraviolet scatterometry by modeling systematic errors
Measurement Science and Technology
2014
25
4
044003
8.43,Scatter-Inv,Scatterometrie, 8.42
http://iopscience.iop.org/article/10.1088/0957-0233/25/4/044003
IOP Publishing
en
0957-0233
10.1088/0957-0233/25/4/044003
M-AHenn
HGross
SHeidenreich
FScholze
CElster
MBär
article
Heidenreich2014
Numerical simulations of a minimal model for the fluid dynamics of dense bacterial suspensions
J.Phys.: Conf. Ser.
2014
490
1
012126
8.43,fluid dynamics
8.43, ActFluid
http://iopscience.iop.org/article/10.1088/1742-6596/490/1/012126
IOP Publishing
en
1742-6596
10.1088/1742-6596/490/1/012126
SHeidenreich
S H LKlapp
MBär
article
Gross2014
Modelling line edge roughness in periodic line-space structures by Fourier optics to improve scatterometry
J. Europ.Opt. Soci.Rap. Pub.
2014
9
14003
In the present paper, we propose a 2D-Fourier transform method as a simple and efficient algorithm for stochastical and numerical studies to investigate the systematic impacts of line edge roughness on light diffraction pattern of periodic line-space structures. The key concept is the generation of ensembles of rough apertures composed of many slits, to calculate the irradiance of the illuminated rough apertures far away from the aperture plane, and a comparison of their light intensities to those of the undisturbed, â€™non-roughâ€™ aperture. We apply the Fraunhofer approximation and interpret the rough apertures as binary 2D-gratings to compute their diffraction patterns very efficiently as the 2D-Fourier transform of the light distribution of the source plane. The rough edges of the aperture slits are generated by means of power spectrum density (PSD) functions, which are often used in metrology of rough geometries. The mean efficiencies of the rough apertures reveal a systematic exponential decrease for higher diffraction orders if compared to the diffraction pattern of the unperturbed aperture. This confirms former results, obtained by rigorous calculations with computational expensive finite element methods (FEM) for a simplified roughness model. The implicated model extension for scatterometry by an exponential damping factor for the calculated efficiencies allows to determine the standard deviation σ<prt>\_</prt> r of line edge roughness along with the critical dimensions (CDs), i.e., line widths, heights and other profile properties in the sub-micrometer range. First comparisons with the corresponding roughness value determined by 3D atomic force microscopy (3D AFM) reveal encouraging results.
Scatterometrie,Scatterometry,atomic force microscopy,line edge roughness,power spectrum density
8.43,Scatter-Inv
http://www.jeos.org/index.php/jeos<prt>\_</prt>rp/article/view/14003
en
1990-2573
10.2971/jeos.2014.14003
HGroß
SHeidenreich
M-AHenn
GDai
FScholze
MBär
article
Geckeler2014
Capabilities and limitations of the self-calibration of angle encoders
Measurement Science and Technology
2014
25
5
055003
8.42,angle encoder,calibration
http://iopscience.iop.org/article/10.1088/0957-0233/25/5/055003
IOP Publishing
en
0957-0233
10.1088/0957-0233/25/5/055003
R DGeckeler
ALink
MKrause
CElster
article
Fortmeier2014
Analytical Jacobian and its application to tilted-wave interferometry
Optics express
2014
22
18
21313--25
Tilted-wave interferometry (TWI) is a novel optical measurement principle for the measurement of aspherical surfaces. For the reconstruction of the wavefront and the surface under test, respectively, perturbation methods are applied, which require the calculation of the Jacobian matrix. For the practical use of the instrument, a fast and exact calculation of the Jacobian matrices is crucial, since this strongly influences the calculation times of the TWI. By applying appropriate approaches in optical perturbation methods we are able to calculate the required Jacobian matrices analytically when the nominal optical path through the system is given. As a result, calculation times for the TWI can be considerably reduced. We finally illustrate the improved TWI procedure and apply methods of optimal design to determine optimal positions of the surface under test. For such applications the fast calculation of the Jacobian matrices is essential.
Aspherics,Interferometry,Mathematical methods (general),Metrology,Surface measurements,TWI,figure,tilted-wave
8.42,EMRP_Form,Form,SimOpt
http://www.osapublishing.org/viewmedia.cfm?uri=oe-22-18-21313<prt>&</prt>seq=0<prt>&</prt>html=true
Optical Society of America
EN
1094-4087
10.1364/OE.22.021313
IFortmeier
MStavridis
AWiegmann
MSchulz
WOsten
CElster
article
Fiebach2014
Uniform global bounds for solutions of an implicit Voronoi finite volume method for reactionâ€“diffusion problems
Numerische Mathematik
2014
128
1
31--72
finite elements,finite volumes,voronoi
8.41
http://link.springer.com/10.1007/s00211-014-0604-6
0029-599X
10.1007/s00211-014-0604-6
AFiebach
AGlitzky
ALinke
article
Elster2014
Bayesian uncertainty analysis compared with the application of the GUM and its supplements
Metrologia
2014
51
4
S159--S166
8.42, Bayesian, Unsicherheit
http://iopscience.iop.org/article/10.1088/0026-1394/51/4/S159
IOP Publishing
en
0026-1394
10.1088/0026-1394/51/4/S159
CElster
article
f3ee8757792015
Numerical investigation of temperature distributions in large storage tanks
Proceedings of Flomeko 2013 16th International Flow Measurement Conference
2013
12
31
8.41, Flow
SSchmelter
RModel
GWendt
MBär
article
JegouNLCR2013
On Phosphate Release in Actin Filaments
Biophysical journal
2013
1
1
104
12
8.43
8.43
equal contributed
10.1016%2Fj.bpj.2013.05.019
AJegou
TNiedermayer
RLipowsky
M.FCarlier
GRomet-Lemonne
article
Heiden_PRL2013
Fluid Dynamics of Bacterial Turbulence
Phys. Rev. Lett.
2013
110
228102
8.43, ActFluid
10.1103/PhysRevLett.110.228102
JDunkel
SHeidenreich
KDrescher
H. HWensink
MBär
R. EGoldstein
article
Radszuweit2013
Intracellular mechanochemical waves in an active poroelastic model
Phys. Rev. Lett.
2013
110
13
138102
Many processes in living cells are controlled by biochemical substances regulating active stresses. The cytoplasm is an active material with both viscoelastic and liquid properties. We incorporate the active stress into a two-phase model of the cytoplasm which accounts for the spatiotemporal dynamics of the cytoskeleton and the cytosol. The cytoskeleton is described as a solid matrix that together with the cytosol as an interstitial fluid constitutes a poroelastic material. We find different forms of mechanochemical waves including traveling, standing, and rotating waves by employing linear stability analysis and numerical simulations in one and two spatial dimensions.
Biological,Biomechanical Phenomena,Cell Physiological Phenomena,Cytoplasm,Cytoplasm: chemistry,Cytoskeleton,Cytoskeleton: chemistry,Elasticity,Extracellular Fluid,Extracellular Fluid: chemistry,Models,Viscosity
8.41, ActMatt, ActFluid
http://www.ncbi.nlm.nih.gov/pubmed/23581377
1079-7114
10.1103/PhysRevLett.110.138102
MRadszuweit
S.Alonso
HEngel
MBär
article
Peruani2013
A kinetic model and scaling properties of non-equilibrium clustering of self-propelled particles
New J. Phys.
2013
15
6
065009
8.41, SPP
http://iopscience.iop.org/article/10.1088/1367-2630/15/6/065009
IOP Publishing
en
doi:10.1088/1367-2630/15/6/065009
1367-2630
10.1088/1367-2630/15/6/065009
FPeruani
MBär
article
Jousten2014
A standard to test the dynamics of vacuum gauges in the millisecond range
Vacuum
2013
100
14--17
Vacuum gauges that control fast processes in industrial applications, e.g. load locks, should immediately react to pressure changes. To study the response time of vacuum gauges to rapid pressure changes, a dynamic vacuum standard was developed where the pressure may change from 100 kPa to 100 Pa within 20 ms in a step-wise manner or within longer times up to 1 s in a predictable manner. This is accomplished by a very fast opening gate valve DN40 and exchangeable orifices and ducts through which the mass flow rate can be calculated by gas flow simulation software. A simple physical model can be used to approximate the calculations. Experiments have been performed with capacitance diaphragm gauges with improved electronics to give a read-out every 0.7 ms. Preliminary results indicate that their response time is at most 1.7 ms, but may be significantly less.
Choked flow,Dynamic pressure,Response time,Vacuum gauge,Vacuum metrology
8.41,Flow
fileadmin/internet/fachabteilungen/abteilung_8/8.4_mathematische_modellierung/8.42/DYNAMIK/842_dynamik_Sensors_2010_10_7621.pdf
http://www.sciencedirect.com/science/article/pii/S0042207X13002546
0042207X
10.1016/j.vacuum.2013.07.037
KJousten
SPantazis
JButhig
RModel
MWüest
JIwicki
article
Jousten2013
Final report of key comparison CCM.P-K12 for very low helium flow rates (leak rates)
Metrologia
2013
50
1A
07001--07001
8.42,KC
http://iopscience.iop.org/article/10.1088/0026-1394/50/1A/07001
IOP Publishing
en
1681-7575
10.1088/0026-1394/50/1A/07001
KJousten
KArai
UBecker
OBodnar
FBoineau
J AFedchak
VGorobey
WJian
DMari
PMohan
JSetina
BToman
MVivcar
Y HYan
article
Wubbeler2013
Simplified evaluation of magnetic field fluctuation thermometry
Measurement Science and Technology
2013
24
11
115004
8.42,Bayes,MFFT,Regression, Unsicherheit
http://iopscience.iop.org/article/10.1088/0957-0233/24/11/115004
IOP Publishing
en
0957-0233
10.1088/0957-0233/24/11/115004
GWübbeler
CElster
article
Bodnar2013a
Application of Bayesian model averaging using a fixed effects model with linear drift for the analysis of key comparison CCM.P-K12
Measurement Techniques
2013
56
6
584--590
8.42,Bayes,KC
http://link.springer.com/10.1007/s11018-013-0249-3
0543-1972
10.1007/s11018-013-0249-3
OBodnar
ALink
KKlauenberg
KJousten
CElster
article
Bodnar2013
Robust Surveillance of Covariance Matrices Using a Single Observation
Sankhya A
2013
76
2
219--256
8.42,statistics
http://link.springer.com/10.1007/s13171-013-0044-x
0976-836X
10.1007/s13171-013-0044-x
OBodnar
TBodnar
YOkhrin
article
Eichstadt2013a
Comparison of the Richardson-Lucy method and a classical approach for spectrometer bandpass correction
Metrologia
2013
50
2
107-118
Bandpass correction in spectrometer measurements using monochromators is often necessaryin order to obtain accurate measurement results. The classical approach of spectrometer bandpass correction is based on local polynomial approximations and the use of ﬁnite differences. Here we compare this approach with an extension of the Richardson–Lucy method, which is well known in image processing, but has not been applied to spectrum bandpass correction yet. Using an extensive simulation study and a practical example, we demonstrate the potential of the Richardson–Lucy method. In contrast to the classical approach, it is robust w.r.t. wavelength step size and measurement noise. In almost all cases the Richardson–Lucy method turns out to be superior to the classical approach both in terms of spectrum estimate and its associated uncertainties.
dynamic measurement, bandwidth correction, spectral estimation, deconvolution
8.42, Dynamik
fileadmin/internet/fachabteilungen/abteilung_8/8.4_mathematische_modellierung/Publikationen_8.4/Eichstaedt_bandwidth_correction.pdf
http://iopscience.iop.org/article/10.1088/0026-1394/50/2/107
IOP Publishing
en
10.1088/0026-1394/50/2/107
SEichstädt
FSchmähling
GWübbeler
KAnhalt
LBünger
UKrüger
CElster
article
Ehret2013
Optical measurement of absolute flatness with the deflectometric measurement systems at PTB
Journal of Physics: Conference Series
2013
425
15
152016
8.42, Form, SimOpt
http://iopscience.iop.org/article/10.1088/1742-6596/425/15/152016
IOP Publishing
en
1742-6588
10.1088/1742-6596/425/15/152016
GEhret
MSchulz
MBaier
AFitzenreiter
article
Dunkel2013
Minimal continuum theories of structure formation in dense active fluids
New J. Phys.
2013
15
4
045016
8.43, ActFluid
http://iopscience.iop.org/article/10.1088/1367-2630/15/4/045016
IOP Publishing
en
1367-2630
10.1088/1367-2630/15/4/045016
JDunkel
SHeidenreich
MBär
R EGoldstein
article
Dahmlow2013
Twists of opposite handedness on a scroll wave
Phys. Rev. Lett.
2013
110
23
234102
The dynamic interaction of scroll waves in the Belousov-Zhabotinsky reaction with a vertically orientated gradient of excitability is studied by optical tomography. This study focuses on scroll waves, whose filaments were oriented almost perpendicular to the gradient. Whereas scroll waves with filaments exactly perpendicular to the gradient remain unaffected, filaments with a component parallel to the gradient develop a twist. Scroll waves with U-shaped filaments exhibit twists starting from both of its ends, resulting in scroll waves whose filaments display a pair of twists of opposite handedness. These twists are separated by a nodal plane where the filament remains straight and untwisted. The experimental findings were reproduced by numerical simulations using the Oregonator model and a linear gradient of excitability almost perpendicular to the orientation of the filament.
Arrhythmias,Cardiac,Cardiac: physiopathology,Heart,Heart: physiology,Models,Theoretical
8.41,Herz
http://www.ncbi.nlm.nih.gov/pubmed/25167496
1079-7114
10.1103/PhysRevLett.110.234102
PDähmlow
S.Alonso
MBär
M J BHauser
article
Alonso2013
Negative tension of scroll wave filaments and turbulence in three-dimensional excitable media and application in cardiac dynamics
Bull. Math. Biol.
2013
75
8
1351--76
Scroll waves are vortices that occur in three-dimensional excitable media. Scroll waves have been observed in a variety of systems including cardiac tissue, where they are associated with cardiac arrhythmias. The disorganization of scroll waves into chaotic behavior is thought to be the mechanism of ventricular fibrillation, whose lethality is widely known. One possible mechanism for this process of scroll wave instability is negative filament tension. It was discovered in 1987 in a simple two variables model of an excitable medium. Since that time, negative filament tension of scroll waves and the resulting complex, often turbulent dynamics was studied in many generic models of excitable media as well as in physiologically realistic models of cardiac tissue. In this article, we review the work in this area from the first simulations in FitzHugh-Nagumo type models to recent studies involving detailed ionic models of cardiac tissue. We discuss the relation of negative filament tension and tissue excitability and the effects of discreteness in the tissue on the filament tension. Finally, we consider the application of the negative tension mechanism to computational cardiology, where it may be regarded as a fundamental mechanism that explains differences in the onset of arrhythmias in thin and thick tissue.
8.41,Animals,Arrhythmias,Cardiac,Cardiac: etiology,Cardiac: physiopathology,Cardiovascular,Electrophysiological Phenomena,Excitation Contraction Coupling,Heart Conduction System,Heart Conduction System: physiology,Hemorheology,Humans,Imaging,Mathematical Concepts,Models,Myocardial Contraction,Three-Dimensional
8.41, Herz
http://www.ncbi.nlm.nih.gov/pubmed/22829178
1522-9602
10.1007/s11538-012-9748-7
SAlonso
A VPanfilov
article
Alonso2013a
Reentry near the percolation threshold in a heterogeneous discrete model for cardiac tissue
Phys. Rev. Lett.
2013
110
15
158101
Arrhythmias in cardiac tissue are related to irregular electrical wave propagation in the heart. Cardiac tissue is formed by a discrete cell network, which is often heterogeneous. A localized region with a fraction of nonconducting links surrounded by homogeneous conducting tissue can become a source of reentry and ectopic beats. Extensive simulations in a discrete model of cardiac tissue show that a wave crossing a heterogeneous region of cardiac tissue can disintegrate into irregular patterns, provided the fraction of nonconducting links is close to the percolation threshold of the cell network. The dependence of the reentry probability on this fraction, the system size, and the degree of excitability can be inferred from the size distribution of nonconducting clusters near the percolation threshold.
Action Potentials,Cardiovascular,Computer Simulation,Heart,Heart: physiology,Models
8.41, Herz, 8.43
http://www.ncbi.nlm.nih.gov/pubmed/25167313
1079-7114
10.1103/PhysRevLett.110.158101
SAlonso
MBär
article
Aranson2013
Viewpoint: The Aquatic Dance of Bacteria
Physics
2013
6
8.41, ActMatter
http://physics.aps.org/articles/v6/61
American Physical Society
en
IAranson
article
Elster2013
Analysis of key comparison data: critical assessment of elements of current practice with suggested improvements
Metrologia
2013
50
5
549--555
8.42,Bayes,KC
http://iopscience.iop.org/article/10.1088/0026-1394/50/5/549
IOP Publishing
en
0026-1394
10.1088/0026-1394/50/5/549
CElster
BToman
phdthesis
Radszuweit2013a
An Active Poroelastic Model for Cytoplasm and Pattern Formation in Protoplasmic Droplets of Physarum Polycephalum
2013
8.41, ActMatter
TU Berlin
MRadszuweit
phdthesis
Kohl2013
Blind separation of dependent source signals for MEG sensory stimulation experiments
2013
8.42,Gehirn,SingleTrial
TU Berlin
PhD Thesis
FKohl
phdthesis
Henn_Thesis
Statistical Approaches to the Inverse Problem of Scatterometry
2013
8.41,8.42,Scatter-Inv,Scatterometrie
8.41,Scatter-Inv
TU Berlin
M-AHenn
phdthesis
Fiebach2013
A dissipative finite volume scheme for reaction-diffusion systems in heterogeneous materials
2013
discrete Moser iteration,dissipative finite volume scheme,heterogeneous materials,reaction-diffusion systems
8.41
http://www.diss.fu-berlin.de/diss/receive/FUDISS<prt>\_</prt>thesis<prt>\_</prt>000000096910
English
AFiebach
article
NiedermayerJCGHRCL2012
Intermittent depolymerization of actin filaments is caused by photo-induced dimerization of actin protomers
Proc. Natl. Acad. Sci. U.S.A.
2012
1
1
109
27
10769--10774
8.43
8.43
equal contributed
10.1073%2Fpnas.1121381109
TNiedermayer
AJegou
LChieze
BGuichard
EHelfer
GRomet-Lemonne
M.FCarlier
RLipowsky
article
Eichstaedt2012a
Efficient implementation of a Monte Carlo method for uncertainty evaluation in dynamic measurements
Metrologia
2012
49
3
401
Measurement of quantities having time-dependent values such as force, acceleration or pressure is a topic of growing importance in metrology. The application of the Guide to the Expression of Uncertainty in Measurement (GUM) and its Supplements to the evaluation of uncertainty for such quantities is challenging. We address the efficient implementation of the Monte Carlo method described in GUM Supplements 1 and 2 for this task. The starting point is a time-domain observation equation. The steps of deriving a corresponding measurement model, the assignment of probability distributions to the input quantities in the model, and the propagation of the distributions through the model are all considered. A direct implementation of a Monte Carlo method can be intractable on many computers since the storage requirement of the method can be large compared with the available computer memory. Two memory-efficient alternatives to the direct implementation are proposed. One approach is based on applying updating formulae for calculating means, variances and point-wise histograms. The second approach is based on evaluating the measurement model sequentially in time. A simulated example is used to compare the performance of the direct and alternative procedures.
8.42, Dynamik, Unsicherheit
10.1088/0026-1394/49/3/401
SEichstädt
ALink
P MHarris
CElster
article
Nevas2012
Simultaneous correction of bandpass and stray-light effects in array spectroradiometer data
Metrologia
2012
49
2
S43--S47
8.42
http://iopscience.iop.org/article/10.1088/0026-1394/49/2/S43
IOP Publishing
en
0026-1394
10.1088/0026-1394/49/2/S43
SNevas
GWübbeler
ASperling
CElster
ATeuber
article
Peruani2012
Collective Motion and Nonequilibrium Cluster Formation in Colonies of Gliding Bacteria
Phys. Rev. Lett.
2012
108
9
098102
8.41, SPP, 8.43
http://link.aps.org/doi/10.1103/PhysRevLett.108.098102
0031-9007
10.1103/PhysRevLett.108.098102
FPeruani
JStarruß
VJakovljevic
LSøgaard-Andersen
ADeutsch
MBär
article
Klauenberg2012
The multivariate normal mean - sensitivity of its objective Bayesian estimates
Metrologia
2012
49
3
395--400
8.42,Bayes,Unsicherheit
http://iopscience.iop.org/article/10.1088/0026-1394/49/3/395
IOP Publishing
en
0026-1394
10.1088/0026-1394/49/3/395
KKlauenberg
CElster
article
Lober2012
Front propagation in one-dimensional spatially periodic bistable media
Phys. Rev. E
2012
86
6 Pt 2
066210
Front propagation in heterogeneous bistable media is studied using the Schl<prt>ö</prt>gl model as a representative example. Spatially periodic modulations in the parameters of the bistable kinetics are taken into account perturbatively. Depending on the ratio L/l (L is the spatial period of the heterogeneity, l is the front width), appropriate singular perturbation techniques are applied to derive an ordinary differential equation for the position of the front in the presence of the heterogeneities. From this equation, the dependence of the average propagation speed on L/l as well as on the modulation amplitude is calculated. The analytical results obtained predict velocity overshoot, different cases of propagation failure, and the propagation speed for very large spatial periods in quantitative agreement with the results of direct numerical simulations of the underlying reaction-diffusion equation.
8.41, exc-media
http://www.ncbi.nlm.nih.gov/pubmed/23368027
1550-2376
10.1103/PhysRevE.86.066210
JLöber
MBär
HEngel
article
Lira2012
Analysis of Key Comparisons Incorporating Knowledge About Bias
IEEE Transactions on Instrumentation and Measurement
2012
61
8
2079--2084
A method is proposed for analyzing key comparison data. It is based on the assumption that each laboratory participating in the comparison exercise obtains independent and consistent estimates of the measurand and that, in addition, each laboratory provides an estimate of the quantity that collects all systematic effects that the laboratory took into account. The unknown value of the latter quantity, subtracted from its estimate, is defined as the laboratory's bias. The uncertainties associated with the estimates of the measurand and with the vanishing biases' estimates are also assumed to be reported. In this paper, we show that the information provided in this way may be of help for judging the performances of the laboratories in their correction of systematic effects. This is done by developing formulas for the final (consensus) estimates and uncertainties of the measurand and of the biases. Formulas for the final estimates and uncertainties of the pairwise differences between the biases are also developed. An example involving simulated key comparison data makes apparent the benefits of the proposed approach.
Atmospheric measurements,Bayesian methods,Bismuth,Gaussian distribution,Laboratories,Measurement uncertainty,Particle measurements,Systematics,Uncertainty,laboratory bias estimation,measurement errors,measurement uncertainty,performance evaluation,statistical analysis,systematic effect,vanishing bias estimation
8.42,KC
http://ieeexplore.ieee.org/lpdocs/epic03/wrapper.htm?arnumber=6189781
0018-9456
10.1109/TIM.2012.2193690
ILira
A GChunovkina
CElster
WWöger
article
Liebert2012
Determination of absorption changes from moments of distributions of times of flight of photons: optimization of measurement conditions for a two-layered tissue model
Journal of biomedical optics
2012
17
5
057005
Time-resolved near-infrared spectroscopy allows for depth-selective determination of absorption changes in the adult human head that facilitates separation between cerebral and extra-cerebral responses to brain activation. The aim of the present work is to analyze which combinations of moments of measured distributions of times of flight (DTOF) of photons and source-detector separations are optimal for the reconstruction of absorption changes in a two-layered tissue model corresponding to extra- and intra-cerebral compartments. To this end we calculated the standard deviations of the derived absorption changes in both layers by considering photon noise and a linear relation between the absorption changes and the DTOF moments. The results show that the standard deviation of the absorption change in the deeper (superficial) layer increases (decreases) with the thickness of the superficial layer. It is confirmed that for the deeper layer the use of higher moments, in particular the variance of the DTOF, leads to an improvement. For example, when measurements at four different source-detector separations between 8 and 35 mm are available and a realistic thickness of the upper layer of 12 mm is assumed, the inclusion of the change in mean time of flight, in addition to the change in attenuation, leads to a reduction of the standard deviation of the absorption change in the deeper tissue layer by a factor of 2.5. A reduction by another 4<prt>%</prt> can be achieved by additionally including the change in variance.
Absorption,Biological,Brain,Brain: metabolism,Computer Simulation,Head,Head: physiology,Humans,Light,Models,Near-Infrared,Near-Infrared: methods,Oximetry,Oximetry: methods,Oxygen,Oxygen: metabolism,Photons,Radiation,Reproducibility of Results,Scattering,Sensitivity and Specificity,Spectroscopy
8.42
http://biomedicaloptics.spiedigitallibrary.org/article.aspx?articleid=1183164
International Society for Optics and Photonics
1560-2281
10.1117/1.JBO.17.5.057005
ALiebert
HWabnitz
CElster
article
Wensink2012
Meso-scale turbulence in living fluids
Proc. Natl. Acad. Sci. U.S.A.
2012
109
36
14308--13
Turbulence is ubiquitous, from oceanic currents to small-scale biological and quantum systems. Self-sustained turbulent motion in microbial suspensions presents an intriguing example of collective dynamical behavior among the simplest forms of life and is important for fluid mixing and molecular transport on the microscale. The mathematical characterization of turbulence phenomena in active nonequilibrium fluids proves even more difficult than for conventional liquids or gases. It is not known which features of turbulent phases in living matter are universal or system-specific or which generalizations of the Navier-Stokes equations are able to describe them adequately. Here, we combine experiments, particle simulations, and continuum theory to identify the statistical properties of self-sustained meso-scale turbulence in active systems. To study how dimensionality and boundary conditions affect collective bacterial dynamics, we measured energy spectra and structure functions in dense Bacillus subtilis suspensions in quasi-2D and 3D geometries. Our experimental results for the bacterial flow statistics agree well with predictions from a minimal model for self-propelled rods, suggesting that at high concentrations the collective motion of the bacteria is dominated by short-range interactions. To provide a basis for future theoretical studies, we propose a minimal continuum model for incompressible bacterial flow. A detailed numerical analysis of the 2D case shows that this theory can reproduce many of the experimentally observed features of self-sustained active turbulence.
Bacillus subtilis,Bacillus subtilis: physiology,Biological,Biomechanical Phenomena,Computer Simulation,Culture Media,Culture Media: chemistry,Hydrodynamics,Models,Movement,Movement: physiology
8.43, ActFluid
http://www.pnas.org/content/109/36/14308
1091-6490
10.1073/pnas.1202032109
H HWensink
JDunkel
SHeidenreich
KDrescher
R EGoldstein
HLöwen
J MYeomans
article
Romanczuk2012
Active Brownian particles
Eur. Phys. J. - Special Topics
2012
202
1
1--162
8.41, SSP
http://www.springerlink.com/index/10.1140/epjst/e2012-01529-y
1951-6355
10.1140/epjst/e2012-01529-y
PRomanczuk
MBär
WEbeling
BLindner
LSchimansky-Geier
article
Starruss2012
Pattern-formation mechanisms in motility mutants of Myxococcus xanthus
Interface focus
2012
2
6
774--85
Formation of spatial patterns of cells is a recurring theme in biology and often depends on regulated cell motility. Motility of the rod-shaped cells of the bacterium Myxococcus xanthus depends on two motility machineries, type IV pili (giving rise to S-motility) and the gliding motility apparatus (giving rise to A-motility). Cell motility is regulated by occasional reversals. Moving M. xanthus cells can organize into spreading colonies or spore-filled fruiting bodies, depending on their nutritional status. To ultimately understand these two pattern-formation processes and the contributions by the two motility machineries, as well as the cell reversal machinery, we analyse spatial self-organization in three M. xanthus strains: (i) a mutant that moves unidirectionally without reversing by the A-motility system only, (ii) a unidirectional mutant that is also equipped with the S-motility system, and (iii) the wild-type that, in addition to the two motility systems, occasionally reverses its direction of movement. The mutant moving by means of the A-engine illustrates that collective motion in the form of large moving clusters can arise in gliding bacteria owing to steric interactions of the rod-shaped cells, without the need of invoking any biochemical signal regulation. The two-engine strain mutant reveals that the same phenomenon emerges when both motility systems are present, and as long as cells exhibit unidirectional motion only. From the study of these two strains, we conclude that unidirectional cell motion induces the formation of large moving clusters at low and intermediate densities, while it results in vortex formation at very high densities. These findings are consistent with what is known from self-propelled rod models, which strongly suggests that the combined effect of self-propulsion and volume exclusion interactions is the pattern-formation mechanism leading to the observed phenomena. On the other hand, we learn that when cells occasionally reverse their moving direction, as observed in the wild-type, cells form small but strongly elongated clusters and self-organize into a mesh-like structure at high enough densities. These results have been obtained from a careful analysis of the cluster statistics of ensembles of cells, and analysed in the light of a coagulation Smoluchowski equation with fragmentation.
,pattern formation
8.41,SPP
http://rsfs.royalsocietypublishing.org/content/2/6/774
2042-8901
10.1098/rsfs.2012.0034
JStarruß
FPeruani
VJakovljevic
LSøgaard-Andersen
ADeutsch
MBär
article
Wubbeler2012
Analysis of magnetic field fluctuation thermometry using Bayesian inference
Measurement Science and Technology
2012
23
12
125004
8.42,Bayes,MFFT,Regression, Unsicherheit
http://iopscience.iop.org/article/10.1088/0957-0233/23/12/125004
IOP Publishing
en
0957-0233
10.1088/0957-0233/23/12/125004
GWübbeler
FSchmähling
JBeyer
JEngert
CElster
article
Toman2012
Alternative analyses of measurements of the Planck constant
Metrologia
2012
49
4
567--571
8.42,Bayes,KC
http://iopscience.iop.org/article/10.1088/0026-1394/49/4/567
IOP Publishing
en
0026-1394
10.1088/0026-1394/49/4/567
BToman
JFischer
CElster
article
Bruns2012
The influence of different vibration exciter systems on high frequency primary calibration of single-ended accelerometers: II
Metrologia
2012
49
1
27--31
dynamic calibration, accelerometer, dynamic measurement
8.42, Dynamik
http://iopscience.iop.org/article/10.1088/0026-1394/49/1/005
IOP Publishing
en
0026-1394
10.1088/0026-1394/49/1/005
TBruns
ALink
ATäubner
article
Bodermann2012
Nanometrology at PTB in support of process control of nanoscale features in semiconductor manufacturing
International Journal of Nanomanufacturing
2012
8
1
We report on recent developments at the PTB in the field of dimensional nanometrology with a special focus on instrumentation, measurement and simulation methods, and standards which are used in semiconductor lithography manufacturing processes. Important dimensional measurands to be controlled precisely during the high volume manufacturing processes of nanoscale features (< 32 nm node) are the positions and widths of features on lithographic masks and wafers as well as the relative positioning or overlay of features.
Nanometrology
8.41,Scatter-Inv
BBodermann
FScholze
JFlügge
HGroß
HBosse
article
Bich2012
Revision of the "Guide to the Expression of Uncertainty in Measurement"
Metrologia
2012
49
6
702--705
8.42,Unsicherheit
http://iopscience.iop.org/article/10.1088/0026-1394/49/6/702
IOP Publishing
en
0026-1394
10.1088/0026-1394/49/6/702
WBich
M GCox
RDybkaer
CElster
W TEstler
BHibbert
HImai
WKool
CMichotte
LNielsen
LPendrill
SSidney
A M Hvan der Veen
WWöger
article
Bar2012
Synchronization and complex dynamics of oscillators with delayed pulse coupling
Angewandte Chemie (International ed. in English)
2012
51
38
9489--90
8.41, NonDyn
http://www.ncbi.nlm.nih.gov/pubmed/22915494
1521-3773
10.1002/anie.201205214
MBär
ESchöll
ATorcini
article
Henn2012a
Improved grating reconstruction by determination of line roughness in extreme ultraviolet scatterometry
Opt. Lett.
2012
37
24
5229--5231
8.43,Scatter-Inv
8.43,Scatter-Inv
10.1364/OL.37.005229
M-AHenn
SHeidenreich
HGroß
ARathsfeld
FScholze
MBär
article
Henn2012
A maximum likelihood approach to the inverse problem of scatterometry
Optics Express
2012
20
12
12771-86
Scatterometry is frequently used as a non-imaging indirect optical method to reconstruct the critical dimensions (CD) of periodic nanostructures. A particular promising direction is EUV scatterometry with wavelengths in the range of 13 - 14 nm. The conventional approach to determine CDs is the minimization of a least squares function (LSQ). In this paper, we introduce an alternative method based on the maximum likelihood estimation (MLE) that determines the statistical error model parameters directly from measurement data. By using simulation data, we show that the MLE method is able to correct the systematic errors present in LSQ results and improves the accuracy of scatterometry. In a second step, the MLE approach is applied to measurement data from both extreme ultraviolet (EUV) and deep ultraviolet (DUV) scatterometry. Using MLE removes the systematic disagreement of EUV with other methods such as scanning electron microscopy and gives consistent results for DUV.
8.43,Diffraction gratings,Metrology,Scatter-Inv,Scatterometrie,8.42
http://www.osapublishing.org/viewmedia.cfm?uri=oe-20-12-12771<prt>&</prt>seq=0<prt>&</prt>html=true
Optical Society of America
EN
1094-4087
10.1364/OE.20.012771
M-AHenn
HGross
FScholze
MWurm
CElster
MBär
article
Elster2012c
On the choice of a noninformative prior for Bayesian inference of discretized normal observations
Computational Statistics
2012
27
2
219--235
8.42,Bayes,Unsicherheit
http://link.springer.com/10.1007/s00180-011-0251-7
0943-4062
10.1007/s00180-011-0251-7
CElster
ILira
article
GrosHHRB2012
Modeling of line roughness and its impact on the diffraction intensities and the reconstructed critical dimensions in scatterometry
Appl. Opt.
2012
51
30
7384--94
We investigate the impact of line-edge and line-width roughness (LER, LWR) on the measured diffraction intensities in angular resolved extreme ultraviolet (EUV) scatterometry for a periodic line-space structure designed for EUV lithography. LER and LWR with typical amplitudes of a few nanometers were previously neglected in the course of the profile reconstruction. The two-dimensional (2D) rigorous numerical simulations of the diffraction process for periodic structures are carried out with the finite element method providing a numerical solution of the 2D Helmholtz equation. To model roughness, multiple calculations are performed for domains with large periods, containing many pairs of line and space with stochastically chosen line and space widths. A systematic decrease of the mean efficiencies for higher diffraction orders along with increasing variances is observed and established for different degrees of roughness. In particular, we obtain simple analytical expressions for the bias in the mean efficiencies and the additional uncertainty contribution stemming from the presence of LER and/or LWR. As a consequence this bias can easily be included into the reconstruction model to provide accurate values for the evaluated profile parameters. We resolve the sensitivity of the reconstruction from this bias by using simulated data with LER/LWR perturbed efficiencies for multiple reconstructions. If the scattering efficiencies are bias-corrected, significant improvements are found in the reconstructed bottom and top widths toward the nominal values.
8.43,Diffraction gratings,Metrology,Scatter-Inv,Scatterometrie
8.43,Scatter-Inv
http://www.osapublishing.org/viewmedia.cfm?uri=ao-51-30-7384<prt>&</prt>seq=0<prt>&</prt>html=true
Optical Society of America
EN
1539-4522
10.1364/AO.51.007384
HGroß
M-AHenn
SHeidenreich
ARathsfeld
MBär
article
Fuser2012
Optoelectronic time-domain characterization of a 100 GHz sampling oscilloscope
Measurement Science and Technology
2012
23
2
025201
We have performed an optoelectronic measurement of the impulse response of an ultrafast sampling oscilloscope with a nominal bandwidth of 100 GHz within a time window of approximately 100 ps. Our experimental technique also considers frequency components above the cut-off frequency of higher-order modes of the 1.0 mm coaxial line, which is shown to be important for the specification of the impulse response of ultrafast sampling oscilloscopes. Additionally, we have measured the reflection coefficient of the sampling head induced by the mismatch of the sampling circuit and the coaxial connector which is larger than 0.5 for certain frequencies. The uncertainty analysis has been done using the Monte Carlo method of Supplement 1 to the ‘Guide to the Expression of Uncertainty in Measurement’ and correlations in the estimated impulse response have been determined. Our measurements extend previous work which deals with the characterization of 70 GHz oscilloscopes and the measurement of 100 GHz oscilloscopes up to the cut-off frequency of higher-order modes.
dynamic measurement, oscilloscope, dynamic calibration, impulse response
8.42,Dynamik
fileadmin/internet/fachabteilungen/abteilung_8/8.4_mathematische_modellierung/Publikationen_8.4/Fueser_Osci_preprint.pdf
http://iopscience.iop.org/article/10.1088/0957-0233/23/2/025201
IOP Publishing
en
0957-0233
10.1088/0957-0233/23/2/025201
HFüser
SEichstädt
KBaaske
CElster
KKuhlmann
RJudaschke
KPierz
MBieler
inbook
Wuebbeler2012c
Assessment of the GUM S1 Adaptive Monte Carlo Scheme
2012
Advanced Mathematical & Computational Tools in Metrology IX
434
8.42, Unsicherheit
F. Pavese, M. Bär, J.M. Limares, C. Perruchet, N.F. Zhang
World Scientific New Jersey
Series on Advances in Mathematics for Applied Sciences
84
54
GWübbeler
P MHarris
M GCox
CElster
inbook
Model_2012
Numerical simulations and turbulent modelling for application in flow metrology
2012
84
8.41, Flow
F. Pavese, M. Bär, J.-R. Filtz, A. B. Forbes, L. Pendrill and K. Shirono
World Scientific, New Jersey
RModel
SSchmelter
GLindner
MBär
inbook
Eichstaedt2012e
Uncertainty evaluation for continuous-time measurements
2012
Advanced Mathematical & Computational Tools in Metrology and Testing IX
126-135
dynamic measurement, continuous function, stochastic process, uncertainty
8.42, Dynamik, Unsicherheit
F. Pavese, M. Bär, J.-R. Filtz, A. B. Forbes, L. Pendrill, K. Shirono
World Scientific New Jersey
Series on Advances in Mathematics for Applied Sciences
84
16
SEichstädt
CElster
inbook
Esward2012
Uncertainty evaluation for traceable dynamic measurement of mechanical quantities: A case study in dynamic pressure calibration
2012
Advanced Mathematical & Computational Tools in Metrology and Testing IX
143-151
dynamic pressure, calibration, dynamic measurement
8.42, Dynamik, Unsicherheit
F. Pavese, M. Bär, J.-R. Filtz, A. B. Forbes, L. Pendrill, K. Shirono
World Scientific New Jersey
Series on Advances in Mathematics for Applied Sciences
84
19
T JEsward
CMatthews
SDownes
AKnott
SEichstädt
CElster
inbook
Gross2012
Stochastic modeling aspects for an improved solution of the inverse problem in scatterometry
2012
8.41,Scatter-Inv
8.41,Scatter-Inv
F. Pavese, M. Bär, J.-R. Filtz, A. B. Forbes, L. Pendrill, K. Shirono
World Scientific New Jersey
Advanced Mathematical & Computational Tools in Metrology and Testing IX
HGroß
M-AHenn
ARathsfeld
MBär
phdthesis
Eichstaedt_Thesis
Analysis of Dynamic Measurements - Evaluation of dynamic measurement uncertainty
2012
Metrology is concerned with the establishment of measurement units and the transfer of measurement standards to industry. International comparability of measurement results requires internationally agreed guidelines for specific measurement tasks and a standardised treatment of measurement uncertain- ties. To this end, the Guide to the Expression of Uncertainty in Measurement (GUM) provides the framework for the evaluation and interpretation of mea- surement uncertainty in metrology. However, it does not address dynamic measurements, which are of growing importance for industry and metrology. Typical examples of dynamic measurements are in-cylinder measurements in the automotive industry (pressure), crash tests (e.g., acceleration and force) or assembly line measurements (e.g., torque and force). A reliable calibra- tion of the measurement systems employed, which can be related to national standards, requires a consistent evaluation of measurement uncertainty for dynamic measurements.The goal of this thesis is to develop a framework for the evaluation of uncer- tainty in dynamic measurements in metrology that are closely related to the treatment of static measurements. The measurement systems considered are those that can be modelled by a linear and time-invariant (LTI) system since such models cover a wide range of metrological applications. The measured values are the values of the system output signal, whereas the values of the quantity of interest serve as the system input signal. Estimation of the in- put signal is considered to be carried out by means of digital filtering in the discrete time domain from which inference of the continuous-time signal is sought.This requires the design of digital filters, an uncertainty evaluation for regu- larised deconvolution and a framework for the definition and propagation of the uncertainty of a continuous function. The design of digital filters for de- convolution is well-established in the signal processing literature. The same holds true for the propagation of variances through LTI systems. However, propagation of variances through uncertain LTI systems for evaluation of uncertainty in the sense of GUM has only recently been considered. The methods developed so far focus on the evaluation of uncertainties and do not address regularisation errors. Moreover, the relation of the discrete-time es- timate to the actual continuous-time measurand has not yet been addressed.We extend the available results for the evaluation of uncertainties to the propagation of associated probability density functions and propose efficient calculation schemes. Moreover, the ill-posed deconvolution problem requires regularisation. We develop a reliable quantitative evaluation of the uncer- tainty contribution due to regularisation assuming a particular type of prior knowledge. We present a framework for the evaluation of uncertainty for con- tinuous measurements, which addresses the definition, assignment and prop- agation of uncertainty. Finally, we develop a technique for the calculation of uncertainty associated with a continuous-time estimate of the measurand from a discrete-time estimate.The proposed techniques provide a complete framework for the consistent and reliable evaluation of uncertainty in the analysis of a dynamic measurement.
dynamic measurement, dynamic uncertainty, digital filter, deconvolution
8.42, Dynamik
fileadmin/internet/fachabteilungen/abteilung_8/8.4_mathematische_modellierung/Publikationen_8.4/842_Dynamik_Diss_Eichstaedt.pdf
Berlin
TU Berlin
PhD Thesis
SEichstädt
article
be2ba9f3062016
Fragmentation Is Crucial for the Steady-State Dynamics of Actin Filaments
Biophysical Journal
2011
1
1
101
4
803--808
8.43
8.43
Elsevier
10.1016%2Fj.bpj.2011.07.009
K.MSchmoller
TNiedermayer
CZensen
CWurm
A.RBausch
article
8541b53b022016
Individual Actin Filaments in a Microfluidic Flow Reveal the Mechanism of {ATP} Hydrolysis and Give Insight Into the Properties of Profilin
PLoS Biology
2011
1
1
9
9
8.43
8.43
equal contributed
Public Library of Science
10.1371/journal.pbio.1001161
AJegou
TNiedermayer
JOrban
RLipowsky
M.FCarlier
GRomet-Lemonne
article
Romero1340
Frequency analysis of atrial fibrillation surface and intracardiac electrograms during pulmonary vein isolation
Europace
2011
13
9
1340--1345
Aims Frequency analysis of atrial electrograms from patients diagnosed with persistent atrial fibrillation (AF) appears to be crucial in its clinical diagnosis. This work explores the fibrillatory frequency properties of both surface and intracardiac electrograms before and after pulmonary vein isolation (PVI) using three time<prt>\textendash</prt>frequency techniques. Methods and results Surface electrocardiograms (ECGs) of 21 patients diagnosed with persistent AF undergoing PVI were recorded. Three methods, Fourier, ensemble average, and wavelet analysis, were used to identify the dominant frequency (DF) in surface ECGs. Dominant frequency was also computed in electrograms recorded within the coronary sinus (CS). Dominant frequency measured within the CS was best estimated in surface lead V1 using both Fourier (relative error: 10.94 <prt>\textpm</prt> 10.37%, correlation: 0.58) and wavelet analysis (relative error: 10.97 <prt>\textpm</prt> 11.08%, correlation: 0.53). Ensemble average gave highest relative error (21.29 <prt>\textpm</prt> 18.07%) and lowest correlation (0.10). Dominant frequency decreased after right PVI. This decrease was significant (P&lt; 0.05) in most of the patients (13, 14, and 7 out of 14 when Fourier, wavelets, and ensemble average was used; 14 in CS). Further isolation of the left pulmonary veins (PVs) yielded a significant (P&lt; 0.05) decrease in only a few of them (3, 4, and 2 out of 14 when Fourier, wavelets, and ensemble average was used; 4 in CS). Conclusion Wavelet and Fourier analysis are good tools for estimating the atrial fibrillatory rate from surface ECG. A drop was observed in the DF value after isolation of the right PV. However, after left PVI this decrease was smaller.
8.42
The Oxford University Press
1099-5129
10.1093/europace/eur104
IRomero
EFleck
CKriatselis
article
Peruani2011
Polar vs. apolar alignment in systems of polar self-propelled particles
J. Phys.: Conf. Ser.
2011
297
1
012014
8.41, SPP
http://iopscience.iop.org/article/10.1088/1742-6596/297/1/012014
IOP Publishing
en
1742-6596
10.1088/1742-6596/297/1/012014
FPeruani
FGinelli
MBär
HChaté
article
Koch2011
A reference dataset for verifying numerical electrophysiological heart models
Biomedical engineering online
2011
10
1
11
BACKGROUND: The evaluation, verification and comparison of different numerical heart models are difficult without a commonly available database that could be utilized as a reference. Our aim was to compile an exemplary dataset. METHODS: The following methods were employed: Magnetic Resonance Imaging (MRI) of heart and torso, Body Surface Potential Maps (BSPM) and MagnetoCardioGraphy (MCG) maps. The latter were recorded simultaneously from the same individuals a few hours after the MRI sessions. RESULTS: A training dataset is made publicly available; datasets for blind testing will remain undisclosed. CONCLUSIONS: While the MRI data may provide a common input that can be applied to different numerical heart models, the verification and comparison of different models can be performed by comparing the measured biosignals with forward calculated signals from the models.
Adult,Body Surface Area,Cardiovascular,Databases,Electrophysiological Processes,Factual,Heart,Heart: physiology,Humans,Magnetic Resonance Imaging,Magnetics,Magnetocardiography,Male,Models,Reference Standards,Reproducibility of Results
8.42
http://www.biomedical-engineering-online.com/content/10/1/11
1475-925X
10.1186/1475-925X-10-11
HKoch
R-DBousseljot
OKosch
CJahnke
IPaetsch
EFleck
BSchnackenburg
article
Klauenberg2011
Bayesian analysis of an international ELISA comparability study
Clinical chemistry and laboratory medicine : CCLM / FESCC
2011
49
9
1459--68
BACKGROUND: Immunoassays are biochemical tests applied to measure even very small amounts of substance using the highly specific binding between an antibody and its antigen. They have a wide range of applications. The measurement however, might be associated with substantial uncertainty; this can have significant consequences for any diagnosis, or clinical decision. An international comparability study was thus performed to assess the sources of uncertainty involved in the estimation of a protein cytokine concentration using a fluorescent ELISA. METHODS: In contrast to the original publication for this international comparability study, we reanalyse the data using Bayesian inference. This provides a statistically coherent approach to estimate ELISA concentrations and their associated uncertainties. RESULTS: The Bayesian uncertainties of individual ELISAs and laboratory estimates are considerably larger than previously reported uncertainties. The average concentrations estimated here differ from the ones estimated by each study participant. In general, this leads to different conclusions about the study. In particular, the inter- and intra-laboratory consistency is increased, and repeatability problems occur for fewer laboratories. CONCLUSIONS: Decisions which are based on plausible ranges of measurements (such as credible intervals), are generally superior to those solely based on point estimates (such as the mean). Reliable uncertainties are thus vital, and not only in metrology. In this paper, a general method is developed to derive concentration estimates and valid uncertainties for ELISAs. Guidance on applying this Bayesian method is provided and the importance of reliable uncertainties associated with ELISAs is underlined. The applicability and virtues of the presented method are demonstrated in the context of an international comparability study.
Bayes Theorem,Calibration,ELISA,Enzyme-Linked Immunosorbent Assay,Enzyme-Linked Immunosorbent Assay: standards,Internationality,Reference Standards,Regression,Uncertainty
8.42, ELISA
http://www.degruyter.com/view/j/cclm.2011.49.issue-9/cclm.2011.648/cclm.2011.648.xml
1437-4331
10.1515/CCLM.2011.648
KKlauenberg
BEbert
JVoigt
MWalzel
J ENoble
A EKnight
CElster
article
Klauenberg2011a
Bayesian Glaciological Modelling to quantify uncertainties in ice core chronologies
Quaternary Science Reviews
2011
30
21-22
2961--2975
Valuable information about the environment and climate of the past is preserved in ice cores which are drilled through ice sheets in polar and alpine regions. A pivotal part of interpreting the information held within the cores is to build ice core chronologies i.e. to relate time to depth. Existing dating methods can be categorised as follows: (1) layer counting using the seasonality in signals, (2) glaciological modelling describing processes such as snow accumulation and plastic deformation of ice, (3) comparison with other dated records, or (4) any combination of these. Conventionally, implementation of these approaches does not use statistical methods. In order to quantify dating uncertainties, in this paper we develop the approach of category (2) further. First, the sources of uncertainty involved in glaciological models are formalised. Feeding these into a statistical framework, that we call Bayesian Glaciological Modelling (BGM), allows us to demonstrate the effect that uncertainty in the glaciological model has on the chronology. BGM may also include additional information to constrain the resulting chronology, for example from layer counting or other dated records such as traces from volcanic eruptions. Our case study involves applying BGM to date an Antarctic ice core (a Dyer plateau core). Working through this example allows us to emphasise the importance of properly assessing uncertain elements in order to arrive at accurate chronologies, including valid dating uncertainties. Valid dating uncertainties, in turn, facilitate the interpretation of environmental and climatic conditions at the location of the ice core as well as the comparison and development of ice core chronologies from different locations.
(Dating) uncertainty,(Hierarchical) linear modelling,Accumulation model,Automatic weather station,Bayes,Bayesian approach,Dyer,Glaciological modelling,Ice core chronology,Layer counting,Likelihood,Posterior distribution,Prior information,Volcanic eruptions
8.42
http://www.sciencedirect.com/science/article/pii/S0277379111000801
02773791
10.1016/j.quascirev.2011.03.008
KKlauenberg
P GBlackwell
C EBuck
RMulvaney
RRöthlisberger
E WWolff
article
Kupitz2011
Surfactant-induced gradients in the three-dimensional Belousov-Zhabotinsky reaction
Phys. Review. E
2011
84
5 Pt 2
056210
Scroll waves are prominent patterns formed in three-dimensional excitable media, and they are frequently considered highly relevant for some types of cardiac arrhythmias. Experimentally, scroll wave dynamics is often studied by optical tomography in the Belousov-Zhabotinsky reaction, which produces CO(2) as an undesired product. Addition of small concentrations of a surfactant to the reaction medium is a popular method to suppress or retard CO(2) bubble formation. We show that in closed reactors even these low concentrations of surfactants are sufficient to generate vertical gradients of excitability which are due to gradients in CO(2) concentration. In reactors open to the atmosphere such gradients can be avoided. The gradients induce a twist on vertically oriented scroll waves, while a twist is absent in scroll waves in a gradient-free medium. The effects of the CO(2) gradients are reproduced by a numerical study, where we extend the Oregonator model to account for the production of CO(2) and for its advection against the direction of gravity. The numerical simulations confirm the role of solubilized CO(2) as the source of the vertical gradient of excitability in reactors closed to the atmosphere.
Algorithms,Animals,Arrhythmias,Biophysics,Biophysics: methods,Bioreactors,Carbon Dioxide,Carbon Dioxide: chemistry,Cardiac,Cardiac: physiopathology,Culture Media,Gases,Humans,Micelles,Models,Sodium Dodecyl Sulfate,Sodium Dodecyl Sulfate: chemistry,Statistical,Surface-Active Agents,Surface-Active Agents: chemistry,Theoretical,Time Factors
8.41, RD
http://www.ncbi.nlm.nih.gov/pubmed/22181487
1550-2376
10.1103/PhysRevE.84.056210
DKupitz
S.Alonso
MBär
M J BHauser
article
Wiegmann2011
Absolute Profilmessung optischer Oberflächen mit Mehrfachsensorsystemen
tm - Technisches Messen
2011
78
4
184--189
8.42,Form,SimOpt
http://www.degruyter.com/view/j/teme.2011.78.issue-4/teme.2011.0102/teme.2011.0102.xml
0171-8096
10.1524/teme.2011.0102
AWiegmann
MSchulz
CElster
article
Wiegmann2011a
Accuracy evaluation for sub-aperture interferometry measurements of a synchrotron mirror using virtual experiments
Precision Engineering
2011
35
2
183--190
We present a virtual experiment for the accuracy assessment of the sub-aperture interferometric measurement of a synchrotron mirror involving several thousand sub-aperture topographies. The virtual experiment simulates the measurement process and accounts for the influence of positioning device errors, interferometer errors, non-perfect calibration of machine geometry as well as errors in the interferometer reference. Two principles are considered for reconstructing the form of a test specimen from the conducted sub-aperture topographies, a stitching procedure and a direct measurement method. The virtual experiments are applied to the task of absolute form measurement (including its radius of curvature) of a synchrotron mirror with a length of 30cm, a width of 4cm, a maximum curvature of about 44mmâˆ’1 and a peak-to-valley of 5mm. As a result, reconstruction accuracies can be expected to be in the range of 100nm when the stitching method is applied, which outperforms the direct measurement method by a factor of about 3.
Interferometry,Simulation,Stitching,Virtual experiment,virtual experiment
8.42,Form,SimOpt
http://www.sciencedirect.com/science/article/pii/S014163591000125X
01416359
10.1016/j.precisioneng.2010.08.007
AWiegmann
MStavridis
MWalzel
FSiewert
TZeschke
MSchulz
CElster
article
Wubbeler2011
Comparison and assessment of procedures for calculating the R(12) line strength of the ν1 + 2 ν2 + ν3 band of CO2
The Journal of Chemical Physics
2011
135
20
204304
Recently, results for the CO(2) R(12) line strength parameter have been reported, which differ significantly and are inconsistent with respect to quoted uncertainties. We investigate to what extent this inconsistency might be caused by the chosen data analysis methods. To this end, we assess and compare a parametric fitting procedure and a non-parametric approach. We apply the methods to simulated and measured line spectra, and we specify the conditions required for the safe application of the two procedures. For our present data, the corresponding conditions are satisfied for both methods, and consistent results are obtained. However, the simulations reveal that the fitting procedure can show shortcomings when the uncertainty in the wavenumber is large.
8.42
http://scitation.aip.org/content/aip/journal/jcp/135/20/10.1063/1.3662134
AIP Publishing
doi:10.1063/1.3662134
1089-7690
10.1063/1.3662134
GWübbeler
G JPadilla Viquez
KJousten
OWerhahn
CElster
article
Bodnar2011
On the application of Supplement 1 to the GUM to non-linear problems
Metrologia
2011
48
5
333--342
8.42,Unsicherheit
http://iopscience.iop.org/article/10.1088/0026-1394/48/5/014
IOP Publishing
en
0026-1394
10.1088/0026-1394/48/5/014
OBodnar
GWübbeler
CElster
article
Echebarria2011
Supernormal conduction in cardiac tissue promotes concordant alternans and action potential bunching
Phys. Rev. E
2011
83
4 Pt 1
040902
Supernormal conduction (SNC) in excitable cardiac tissue refers to an increase of pulse (or action potential) velocity with decreasing distance to the preceding pulse. Here we employ a simple ionic model to study the effect of SNC on the propagation of action potentials (APs) and the phenomenology of alternans in excitable cardiac tissue. We use bifurcation analysis and simulations to study attraction between propagating APs caused by SNC that leads to AP pairs and bunching. It is shown that SNC stabilizes concordant alternans in arbitrarily long paced one-dimensional cables. As a consequence, spiral waves in two-dimensional tissue simulations exhibit straight nodal lines for SNC in contrast to spiraling ones in the case of normal conduction.
Action Potentials,Action Potentials: physiology,Animals,Biological Clocks,Biological Clocks: physiology,Cardiovascular,Computer Simulation,Heart Conduction System,Heart Conduction System: physiology,Humans,Models
8.41, Herz
http://www.ncbi.nlm.nih.gov/pubmed/21599107
1550-2376
10.1103/PhysRevE.83.040902
BEchebarria
GRöder
HEngel
JDavidsen
MBär
article
Alonso2011a
Complex wave patterns in an effective reaction-diffusion model for chemical reactions in microemulsions
J. Chem. Phys.
2011
134
9
094117
An effective medium theory is employed to derive a simple qualitative model of a pattern forming chemical reaction in a microemulsion. This spatially heterogeneous system is composed of water nanodroplets randomly distributed in oil. While some steps of the reaction are performed only inside the droplets, the transport through the extended medium occurs by diffusion of intermediate chemical reactants as well as by collisions of the droplets. We start to model the system with heterogeneous reaction-diffusion equations and then derive an equivalent effective spatially homogeneous reaction-diffusion model by using earlier results on homogenization in heterogeneous reaction-diffusion systems [S.Alonso, M.BaÌˆr, and R.Kapral, J. Chem. Phys. 134, 214102 (2009)]. We study the linear stability of the spatially homogeneous state in the resulting effective model and obtain a phase diagram of pattern formation, that is qualitatively similar to earlier experimental results for the Belousov-Zhabotinsky reaction in an aerosol OT (AOT)-water-in-oil microemulsion [V.K.Vanag and I.R.Epstein, Phys. Rev. Lett. 87, 228301 (2001)]. Moreover, we reproduce many patterns that have been observed in experiments with the Belousov-Zhabotinsky reaction in an AOT oil-in-water microemulsion by direct numerical simulations.
Aerosols,Aerosols: chemistry,Chemical,Diffusion,Emulsions,Emulsions: chemistry,Models,Oils,Oils: chemistry,Water,Water: chemistry
8.41, RD
http://scitation.aip.org/content/aip/journal/jcp/134/9/10.1063/1.3559154
AIP Publishing
1089-7690
10.1063/1.3559154
S.Alonso
KJohn
MBär
article
Alonso2011
Oscillations in the lateral pressure of lipid monolayers induced by nonlinear chemical dynamics of the second messengers MARCKS and protein kinase C
Biophys. J.
2011
100
4
939--47
The binding of the MARCKS peptide to the lipid monolayer containing PIP(2) increases the lateral pressure of the monolayer. The unbinding dynamics modulated by protein kinase C leads to oscillations in lateral pressure of lipid monolayers. These periodic dynamics can be attributed to changes in the crystalline lipid domain size. We have developed a mathematical model to explain these observations based on the changes in the physical structure of the monolayer by the translocation of MARCKS peptide. The model indicates that changes in lipid domain size drives these oscillations. The model is extended to an open system that sustains chemical oscillations.
Biological,Biological Transport,Computer Simulation,Fluorescence,Intracellular Signaling Peptides and Proteins,Intracellular Signaling Peptides and Proteins: met,Lipids,Lipids: chemistry,Membrane Proteins,Membrane Proteins: metabolism,Microscopy,Models,Nonlinear Dynamics,Phosphorylation,Pressure,Protein Kinase C,Protein Kinase C: metabolism,Second Messenger Systems,Time Factors
8.41,membrane
http://www.sciencedirect.com/science/article/pii/S0006349510052197
1542-0086
10.1016/j.bpj.2010.12.3702
S.Alonso
UDietrich
CHändel
J AKäs
MBär
article
Alonso2011c
Effects of reduced discrete coupling on filament tension in excitable media
Chaos
2011
21
1
013118
Wave propagation in the heart has a discrete nature, because it is mediated by discrete intercellular connections via gap junctions. Although effects of discreteness on wave propagation have been studied for planar traveling waves and vortexes (spiral waves) in two dimensions, its possible effects on vortexes (scroll waves) in three dimensions are not yet explored. In this article, we study the effect of discrete cell coupling on the filament dynamics in a generic model of an excitable medium. We find that reduced cell coupling decreases the line tension of scroll wave filaments and may induce negative filament tension instability in three-dimensional excitable lattices.
8.41 exc-media
http://scitation.aip.org/content/aip/journal/chaos/21/1/10.1063/1.3551500
AIP Publishing
1089-7682
10.1063/1.3551500
S.Alonso
MBär
AlVPanfilov
article
Elster2011a
Bayesian uncertainty analysis for a regression model versus application of GUM Supplement 1 to the least-squares estimate
Metrologia
2011
48
5
233--240
8.42, Regression, Unsicherheit
http://iopscience.iop.org/article/10.1088/0026-1394/48/5/001
IOP Publishing
en
0026-1394
10.1088/0026-1394/48/5/001
CElster
BToman
article
Forster2011
Untersuchungen zur Explosionsgefahr beim Umschlag von Kerosin Jet A-1
Technische Sicherheit
2011
1
18--27
8.41, Flow
HFörster
WGünther
GLindner
RModel
article
Fruhner_CC2010
Modelling the influence of cardiac motion on electrical excitation and the magnetocardiogram
Comp. Cardiology
2010
37
867
8.41, Herz
SFruhner
HEngel
MBär
article
Peruani2011a
Cluster dynamics and cluster size distributions in systems of self-propelled particles
Eur. Phys. J-Special Topics
2010
191
1
173--185
8.41, SSP
http://www.springerlink.com/index/10.1140/epjst/e2010-01349-1
1951-6355
10.1140/epjst/e2010-01349-1
FPeruani
LSchimansky-Geier
MBär
article
Kohl2010
Shifted factor analysis for the separation of evoked dependent MEG signals
Physics in medicine and biology
2010
55
15
4219--30
Decomposition of evoked magnetoencephalography (MEG) data into their underlying neuronal signals is an important step in the interpretation of these measurements. Often, independent component analysis (ICA) is employed for this purpose. However, ICA can fail as for evoked MEG data the neuronal signals may not be statistically independent. We therefore consider an alternative approach based on the recently proposed shifted factor analysis model, which does not assume statistical independence of the neuronal signals. We suggest the application of this model in the time domain and present an estimation procedure based on a Taylor series expansion. We show in terms of synthetic evoked MEG data that the proposed procedure can successfully separate evoked dependent neuronal signals while standard ICA fails. Latency estimation of neuronal signals is an inherent part of the proposed procedure and we demonstrate that resulting latency estimates are superior to those obtained by a maximum likelihood method.
Evoked Potentials,Humans,Magnetoencephalography,Magnetoencephalography: methods,Models, Statistical,Neurons,Neurons: cytology,SingleTrial
8.42, Gehirn, SingleTrial
http://iopscience.iop.org/article/10.1088/0031-9155/55/15/002
IOP Publishing
en
1361-6560
10.1088/0031-9155/55/15/002
FKohl
GWübbeler
DKolossa
MBär
ROrglmeister
CElster
article
Leistner2010
Magnetoencephalography discriminates modality-specific infraslow signals less than 0.1 Hz
NeuroReport
2010
21
3
196--200
8.42, Gehirn
SLeistner
TSander
GWübbeler
ALink
CElster
GCurio
LTrahms
B MMackert
article
Wiegmann2010
Improving the lateral resolution of a multi-sensor profile measurement method by non-equidistant sensor spacing
Optics express
2010
18
15
15807--19
We present a method to enhance the achievable lateral resolution of a multi-sensor scanning profile measurement method. The relationship between the profile measurement method considered and established shearing techniques is illustrated. Simulation and measurement results show that non-equidistant sensor spacing can improve the lateral resolution significantly.
Image recognition,Instrumentation,Interferometry,Metrology,Surface measurements,algorithms and filters,and metrology,figure,measurement
8.42, Form, SimOpt
http://www.osapublishing.org/viewmedia.cfm?uri=oe-18-15-15807<prt>&</prt>seq=0<prt>&</prt>html=true
Optical Society of America
EN
1094-4087
10.1364/OE.18.015807
AWiegmann
MSchulz
CElster
article
Schulz2010
Concept, design and capability analysis of the new Deflectometric Flatness Reference at PTB
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
2010
616
2-3
134--139
At PTB, a new setup for the highly accurate topography measurement of nearly flat optical surfaces is now under construction. The so-called Deflectometric Flatness Reference (DFR) is designed to measure in the direct deflectometric mode by applying an autocollimator and a scanning pentaprism, and in the difference deflectometric mode corresponding to the Extended Shear Angle Difference (ESAD) principle invented by PTB. With the new DFR instrument, horizontally as well as vertically orientated specimens with dimensions of up to 1m and a mass of up to 120kg will be measurable. The design of the new instrument is supported by employing a comprehensive simulation environment developed for dimensional measuring machines. The mechanical and optical concept is illustrated together with the current design of the DFR setup. Results from the simulations are presented to derive requirements for tolerated mechanical stage deviations and alignment accuracies.
ESAD,Flatness measurement,Nanometrology,Simulation
8.42,Deflectometry,Form,SimOpt
http://www.sciencedirect.com/science/article/pii/S0168900209020592
01689002
10.1016/j.nima.2009.10.108
MSchulz
GEhret
MStavridis
CElster
article
Sander2010
Recent advances in modeling and analysis of bioelectric and biomagnetic sources
Biomedizinische Technik. Biomedical engineering
2010
55
2
65--76
Determining the centers of electrical activity in the human body and the connectivity between different centers of activity in the brain is an active area of research. To understand brain function and the nature of cardiovascular diseases requires sophisticated methods applicable to non-invasively measured bioelectric and biomagnetic data. As it is difficult to solve for all unknown parameters at once, several strains of data analysis have been developed, each trying to solve a different part of the problem and each requiring a different set of assumptions. Current trends and results from major topics of electro- and magnetoencephalographic data analysis are presented here together with the aim of stimulating research into the unification of the different approaches. The following topics are discussed: source reconstruction using detailed finite element modeling to locate sources deep in the brain; connectivity analysis for the quantification of strength and direction of information flow between activity centers, preferably incorporating an inverse solution; the conflict between the statistical independence assumption of sources and a possible connectivity; the verification and validation of results derived from non-invasively measured data through animal studies and phantom measurements. This list already indicates the benefits of a unified view.
Action Potentials,Action Potentials: physiology,Animals,Brain,Brain Mapping,Brain Mapping: methods,Brain Mapping: trends,Brain: physiology,Computer Simulation,Electroencephalography,Electroencephalography: methods,Electroencephalography: trends,Electromagnetic Fields,Humans,Models,Neurological,Radiometry,Radiometry: methods,Radiometry: trends,SingleTrial
8.42, Gehirn
http://www.degruyter.com/view/j/bmte.2010.55.issue-2/bmt.2010.027/bmt.2010.027.xml
1862-278X
10.1515/BMT.2010.027
T HSander
T RKnösche
ASchlögl
FKohl
C HWolters
JHaueisen
LTrahms
article
Radszuweit2011
A model for oscillations and pattern formation in protoplasmic droplets of Physarum polycephalum
Eur. Phys. J. - Special Topics
2010
191
1
159--172
8.41,pattern formation
8.41, ActMatter, ActFluid
http://www.springerlink.com/index/10.1140/epjst/e2010-01348-2
1951-6355
10.1140/epjst/e2010-01348-2
MRadszuweit
HEngel
MBär
article
Wubbeler2010
A two-stage procedure for determining the number of trials in the application of a Monte Carlo method for uncertainty evaluation
Metrologia
2010
47
3
317--324
8.42,Unsicherheit
http://iopscience.iop.org/article/10.1088/0026-1394/47/3/023
IOP Publishing
en
0026-1394
10.1088/0026-1394/47/3/023
GWübbeler
P MHarris
M GCox
CElster
article
Eichstadt2010i
Dynamic uncertainty for compensated second-order systems
Sensors
2010
10
8
7621-31
The compensation of LTI systems and the evaluation of the according uncertainty is of growing interest in metrology. Uncertainty evaluation in metrology ought to follow specific guidelines, and recently two corresponding uncertainty evaluation schemes have been proposed for FIR and IIR filtering. We employ these schemes to compare an FIR and an IIR approach for compensating a second-order LTI system which has relevance in metrology. Our results suggest that the FIR approach is superior in the sense that it yields significantly smaller uncertainties when real-time evaluation of uncertainties is desired.
dynamic model, digital filter, deconvolution, dynamic measurement
8.42, Dynamik
http://www.mdpi.com/1424-8220/10/8/7621/htm
Molecular Diversity Preservation International
en
10.3390/s100807621
SEichstädt
ALink
CElster
article
Eichstadt2010k
On-line dynamic error compensation of accelerometers by uncertainty-optimal filtering
Measurement
2010
43
5
708-713
The output signal of an accelerometer typically contains dynamic errors when a broadband acceleration is applied. In order to determine the applied acceleration, post-processing of the accelerometerâ€™s output signal is required. To this end, we propose the application of a digital FIR filter. We evaluate the uncertainty associated with the filtered output signal and give explicit formulae which allow for on-line calculation. In this way, estimation of the applied acceleration and the calculation of associated uncertainties may be carried out during the measurement. The resulting uncertainties can strongly depend on the design of the applied filter and we describe a simple method to construct an uncertainty-optimal filter. The benefit of the proposed procedures is illustrated by means of simulated measurements.
Accelerometer,Digital filter,Dynamic measurements,Dynamik,Uncertainty
8.42, Dynamik, Unsicherheit
http://www.sciencedirect.com/science/article/pii/S0263224110000023
10.1016/j.measurement.2009.12.028
SEichstädt
ALink
TBruns
CElster
article
Eichstadt2010j
Deconvolution filters for the analysis of dynamic measurement processes: a tutorial
Metrologia
2010
47
5
522-533
deconvolution, digital filter, dynamic measurement
8.42, Dynamik
IOP Publishing
en
10.1088/0026-1394/47/5/003
SEichstädt
CElster
T JEsward
J PHessling
article
Alonso2010a
Wave propagation in heterogeneous bistable and excitable media
Eur. Phys. J. - Special Topics
2010
187
1
31--40
8.41, exc-Media
http://www.springerlink.com/index/10.1140/epjst/e2010-01268-1
1951-6355
10.1140/epjst/e2010-01268-1
SAlonso
JLöber
MBär
HEngel
article
Alonso2011b
Self-organization processes at active interfaces
The European Physical Journal Special Topics
2010
191
1
131--145
8.41, SO
http://www.springerlink.com/index/10.1140/epjst/e2010-01346-4
1951-6355
10.1140/epjst/e2010-01346-4
SAlonso
H-YChen
MBär
A SMikhailov
article
Alonso2010
Phase separation and bistability in a three-dimensional model for protein domain formation at biomembranes
Phys. Biol.
2010
7
4
046012
Proteins in living cells interact with membranes. They may bind to or unbind from the membrane to the cytosol depending on the lipid composition of the membrane and their interaction with cytosolic enzymes. Moreover, proteins can accumulate at the membrane and assemble in spatial domains. Here, a simple model of protein cycling at biomembranes is studied, when the total number of proteins is conserved. Specifically, we consider the spatio-temporal dynamics of MARCKS proteins and their interactions with enzymes facilitating translocation from and rebinding to the membrane. The model exhibits two qualitatively different mechanisms of protein domain formation: phase separation related to a long-wave instability of a membrane state with homogeneous protein coverage and stable coexistence of two states with different homogeneous protein coverage in bistable media. We evaluate the impact of the cytosolic volume on the occurrence of protein pattern formation by simulations in a three-dimensional model. We show that the explicit treatment of the volume in the model leads to an effective rescaling of the reaction rates. For a simplified model of protein cycling, we can derive analytical expressions for the rescaling coefficients and verify them by direct simulations with the complete three-dimensional model.
Cell Membrane,Cell Membrane: chemistry,Cytosol,Cytosol: chemistry,Diffusion,Membrane Lipids,Membrane Lipids: chemistry,Membrane Proteins,Membrane Proteins: chemistry,Models,Molecular
8.41,Membrane
http://iopscience.iop.org/article/10.1088/1478-3975/7/4/046012
IOP Publishing
doi:10.1088/1478-3975/7/4/046012
1478-3975
10.1088/1478-3975/7/4/046012
SAlonso
MBär
article
Gross2010
Investigations on a robust profile model for the reconstruction of 2D periodic absorber lines in scatterometry
J. Europ. Opt. Soc. Rap. Public.
2010
5
10053
Scatterometry as a non-imaging indirect optical method in wafer metrology is applicable to lithography masks designed for extreme ultraviolet (EUV) lithography , where light with wavelengths of about 13.5 nm is applied. The main goal is to reconstruct the critical dimensions (CD) of the mask, i.e., profile parameters such as line width, line height, and side-wall angle, from the measured diffracted light pattern and to estimate the associated uncertainties. The numerical simulation of the diffraction process for periodic 2D structures can be realized by the finite element solution of the two-dimensional Helmholtz equation. The inverse problem is expressed as a non-linear operator equation where the operator maps the sought mask parameters to the efficiencies of the diffracted plane wave modes. To solve this operator equation, the deviation of the measured efficiencies from the ones obtained computationally is minimized by a Gauss-Newton type iterative method. In the present paper, the admissibility of rectangular profile models for the evaluations of CD uniformity is studied. More precisely, several sets of typical measurement data are simulated for trapezoidal shaped EUV masks with different mask signatures characterized by various line widths, heights and side-wall angles slightly smaller than 90 degree. Using these sets, but assuming rectangular structures as the basic profiles of the numerical reconstruction algorithm, approximate line height and width parameters are determined as the critical dimensions of the mask. Finally, the model error due to the simplified shapes is analyzed by checking the deviations of the reconstructed parameters from their nominal values.
Scatterometrie,critical dimensions (CD),inverse problem,profile model,scatterometry
8.41,Scatter-Inv
http://www.jeos.org/index.php/jeos<prt>\_</prt>rp/article/view/10053
en
1990-2573
10.2971/jeos.2010.10053
HGross
JRichter
ARathsfeld
MBär
article
Henn2010
Hyponormal and strongly hyponormal matrices in inner product spaces
Linear Algebra and its Applications
2010
433
6
1055--1076
Complex matrices that are structured with respect to a possibly degenerate indefinite inner product are studied. Based on earlier works on normal matrices, the notions of hyponormal and strongly hyponormal matrices are introduced. A full characterization of such matrices is given and it is shown how those matrices are related to different concepts of normal matrices in degenerate inner product spaces. Finally, the existence of invariant semidefinite subspaces for strongly hyponormal matrices is discussed.
Adjoint,Degenerate inner product,H-Hyponormal,Invariant semidefinite subspace,Linear relations,Primary: 15A57,Secondary: 15A63,Strongly H-hyponormal
8.41,
http://www.sciencedirect.com/science/article/pii/S0024379510002880
00243795
10.1016/j.laa.2010.04.050
M-AHenn
CMehl
CTrunk
article
Elster2010
Analysis of key comparisons: estimating laboratories' biases by a fixed effects model using Bayesian model averaging
Metrologia
2010
47
3
113--119
8.42,Bayes,KC
http://iopscience.iop.org/article/10.1088/0026-1394/47/3/001
IOP Publishing
en
0026-1394
10.1088/0026-1394/47/3/001
CElster
BToman
article
Elster2010a
Linking of a RMO key comparison to a related CIPM key comparison using the degrees of equivalence of the linking laboratories
Metrologia
2010
47
1
96--102
8.42,KC
http://iopscience.iop.org/article/10.1088/0026-1394/47/1/011
IOP Publishing
en
0026-1394
10.1088/0026-1394/47/1/011
CElster
A GChunovkina
WWöger
article
Ginelli2010
Large-scale collective properties of self-propelled rods
Phys. Rev. Lett.
2010
104
18
184502
We study, in two space dimensions, the collective properties of constant-speed polar point particles interacting locally by nematic alignment in the presence of noise. This minimal approach to self-propelled rods allows one to deal with large numbers of particles, which exhibit a rich phenomenology distinctively different from all other known models for self-propelled particles. Extensive simulations reveal long-range nematic order, phase separation, and space-time chaos mediated by large-scale segregated structures.
8.41, SPP, 8.43
http://www.ncbi.nlm.nih.gov/pubmed/20482178
1079-7114
10.1103/PhysRevLett.104.184502
FGinelli
FPeruani
MBär
HChaté
article
Link2009b
Uncertainty evaluation for IIR (infinite impulse response) filtering using a state-space approach
Measurement Science and Technology
2009
20
5
055104
dynamic measurement, digital filter, deconvolution, dynamic uncertainty
8.42,Dynamik, Unsicherheit
IOP Publishing
10.1088/0957-0233/20/5/055104
ALink
CElster
article
Wiegmann2009
Suppression of aliasing in multi-sensor scanning absolute profile measurement
Optics Express
2009
17
13
11098
The task of anti-aliasing in absolute profile measurement by multi-sensor scanning techniques is considered. Simulation results are presented which demonstrate that aliasing can be highly reduced by a suitable choice of the scanning steps. The simulation results were confirmed by results obtained for interferometric measurements (Nyquist frequency 1/646 μm-1) on a specifically designed chirp specimen with sinusoidal waves of amplitude 100 nm and wavelengths from 2.5 mm down to 19 μm.
Image recognition,Instrumentation,Interferometry,Metrology,Surface measurements,algorithms and filters,and metrology,figure,measurement
8.42, Form, SimOpt
http://www.osapublishing.org/viewmedia.cfm?uri=oe-17-13-11098<prt>&</prt>seq=0<prt>&</prt>html=true
Optical Society of America
EN
1094-4087
10.1364/OE.17.011098
AWiegmann
MSchulz
CElster
article
Wubbeler2009
Determination of the Complex Residual Error Parameters of a Calibrated One-Port Vector Network Analyzer
IEEE Transactions on Instrumentation and Measurement
2009
58
9
3238--3244
A novel approach for the determination of the complex residual error parameters of a calibrated one-port vector network analyzer (VNA) is proposed. The method is based on a single-reflection measurement employing a high-precision airline terminated by a short. The complex-valued residual directivity and source match are extracted over the entire measured frequency range by applying a sophisticated data analysis scheme utilizing low-pass filtering and linear prediction. By including an additional reflection measurement of the utilized short, the method allows the residual reflection tracking to be evaluated. Based on numerical simulations, advisable settings of method parameters are determined. In addition to the verification of the VNA calibration, the complex residual error parameters can be used for a second-order correction of the measured data. The significant enhancement of accuracy, which can be achieved this way, is demonstrated for standard calibrations by comparing the second-order corrected reflection data with results obtained from the well-established cross-ratio (quarter-wave) method.
Calibration,calibration,complex residual error parameter determination,complex-valued residual directivity,cross-ratio method,data analysis scheme,high-precision airline,linear prediction,low-pass filtering,low-pass filters,network analysers,one-port vector network analyzer,residual error parameter,second-order correction,single-reflection measurement,vector network analyzer (VNA),verification
8.42
http://ieeexplore.ieee.org/lpdocs/epic03/wrapper.htm?arnumber=5175350
0018-9456
10.1109/TIM.2009.2017170
GWübbeler
CElster
TReichel
RJudaschke
article
Chunovkina2009
Evaluating systematic differences between laboratories in interlaboratory comparisons
Measurement Techniques
2009
52
7
788--793
8.42,KC
http://link.springer.com/10.1007/s11018-009-9340-1
0543-1972
10.1007/s11018-009-9340-1
A GChunovkina
CElster
ILira
WWöger
article
Gross2009
Profile reconstruction in extreme ultraviolet (EUV) scatterometry: modeling and uncertainty estimates
Measurement Science and Technology
2009
20
10
105102
8.41,Scatter-EUV,Scatter-Inv,Scatterometrie
8.41,Scatter-Inv
http://iopscience.iop.org/article/10.1088/0957-0233/20/10/105102
IOP Publishing
en
0957-0233
10.1088/0957-0233/20/10/105102
HGross
ARathsfeld
FScholze
MBär
article
Elster2009
Bayesian uncertainty analysis under prior ignorance of the measurand versus analysis using the Supplement 1 to the Guide : a comparison
Metrologia
2009
46
3
261--266
8.42,Bayes,Unsicherheit
http://iopscience.iop.org/article/10.1088/0026-1394/46/3/013
IOP Publishing
en
0026-1394
10.1088/0026-1394/46/3/013
CElster
BToman
inbook
Lira2009
Derivation of an output PDF from Bayes theorem and the principle of maximum entropy
2009
Advanced Mathematical & Computational Tools in Metrology VIII
213
8.42, Unsicherheit
F. Pavese, M. Bär, J.M. Limares, C. Perruchet, N.F. Zhang
World Scientific New Jersey
Series on Advances in Mathematics for Applied Sciences
78
31
ILira
CElster
WWöger
M GCox
inbook
Wuebbeler2009
Impact of correlation in the measured frequency response on the results of a dynamic calibration
2009
Advanced Mathematical & Computational Tools in Metrology VIII
369-374
dynamic measurement, frequency response, dynamic calibration
8.42, Dynamik, Unsicherheit
F. Pavese, M. Bär, J.M. Limares, C. Perruchet, N.F. Zhang
World Scientific New Jersey
Series on Advances in Mathematics for Applied Sciences
78
52
GWübbeler
ALink
TBruns
CElster
inbook
Elster2009m
Analysis of dynamic measurements: compensation of dynamic error and evaluation of uncertainty
2009
Advanced Mathematical & Computational Tools in Metrology VIII
80-89
8.42, Dynamik, Unsicherheit
F. Pavese, M. Bär, J.M. Limares, C. Perruchet, N.F. Zhang
World Scientific New Jersey
Series on Advances in Mathematics for Applied Sciences
78
13
CElster
ALink
phdthesis
Wiegmann2009a
Multiple Sensorsysteme zur Topographiebestimmung optischer Oberflächen
2009
8.42,Form, SimOpt
http://dx.doi.org/10.14279/depositonce-2278
TU Berlin
PhD Thesis
AWiegmann
article
NiedermayerEL2013
Synchronization, phase locking, and metachronal wave formation in ciliary chains
Chaos
2008
1
1
18
8.43
8.43
10.1063/1.2956984
TNiedermayer
BEckhardt
PLenz
article
Model2008
A scatterometry inverse problem in optical mask metrology
Journal of Physics: Conference Series
2008
135
1
012071
8.41,Scatter-Inv,Scatterometrie
8.41,Scatter-Inv
http://iopscience.iop.org/article/10.1088/1742-6596/135/1/012071
IOP Publishing
en
1742-6596
10.1088/1742-6596/135/1/012071
RModel
ARathsfeld
HGross
MWurm
BBodermann
article
Knappe-Grueneberg2008
Influence of demagnetization coil configuration on residual field in an extremely magnetically shielded room: Model and measurements
Journal of Applied Physics
2008
103
7
07E925
The Berlin magnetically shielded room 2 (BMSR-2) features a magnetic residual field below 500 pT and a field gradient level less than 0.5 pT âˆ• mm , which are needed for very sensitive human biomagnetic recordings or low field NMR. Nevertheless, below 15 Hz , signals are compromised by an additional noise contribution due to vibration forced sensor movements in the field gradient. Due to extreme shielding, the residual field and its homogeneity are determined mainly by the demagnetization results of the mumetal shells. Eight different demagnetization coil configurations can be realized, each results in a characteristic field pattern. The spatial dc flux density inside BMSR-2 is measured with a movable superconducting quantum interference device system with an accuracy better than 50 pT . Residual field and field distribution of the current-driven coils fit well to an air-core coil model, if the high permeable core and the return lines outside of the shells are neglected. Finally, we homogenize the residual field by selecting a proper coil configuration.
8.42
http://scitation.aip.org/content/aip/journal/jap/103/7/10.1063/1.2837876
AIP Publishing
00218979
10.1063/1.2837876
SKnappe-Grueneberg
ASchnabel
GWübbeler
MBurghoff
article
Wiegmann2008
Absolute profile measurement of large moderately flat optical surfaces with high dynamic range
Optics Express
2008
16
16
11975
We present a novel procedure for absolute, highly-accurate profile measurement with high dynamic range for large, moderately flat optical surfaces. The profile is reconstructed from many sub-profiles measured by a small interferometer which is scanned along the specimen under test. Additional angular and lateral distance measurements are used to account for the tilt of the interferometer and its precise lateral location during the measurements. Accurate positioning of the interferometer is not required. The algorithm proposed for the analysis of the data allows systematic errors of the interferometer and height offsets of the scanning stage to be eliminated and it does not reduce the resolution. By utilizing a realistic simulation scenario we show that accuracies in the nanometer range can be reached.
Image recognition,Instrumentation,Interferometry,Metrology,Surface measurements,algorithms and filters,and metrology,figure,measurement
8.42, Form, SimOpt
http://www.osapublishing.org/viewmedia.cfm?uri=oe-16-16-11975<prt>&</prt>seq=0<prt>&</prt>html=true
Optical Society of America
EN
1094-4087
10.1364/OE.16.011975
AWiegmann
MSchulz
CElster
article
Schulz2008
Optical flatness metrology: 40 years of progress
Opt. Pura Apl
2008
41
325
Optical flatness metrology has improved significantly in the last decades due to novel measurement tools and new math-based methods. An overview is given summarizing the most important optical techniques for flatness metrology at the nanometer level. The capabilities of modern methods such as the interferometric three-flat test accompanied by a computer-aided evaluation, the Traceable Multi Sensor method as an improved stitching method, and difference deflectometry represented by the Extended Shear Angle Difference method are reviewed.
Open Access
Deflectometry, Interferometry, Mathematical methods, Metrology, Optical inspection
8.42, SimOpt, Form
http://www.sedoptica.es/Menu_Volumenes/pdfs/314.pdf
Opt. Pura Apl
10.2971/jeos.2010.10011
MSchulz
AWiegmann
AMarquez
CElster
article
Romero
Study of surface electrocardiogram spectrum before and after pulmonary vein ablation in patients with persistent atrial fibrillation
Journal of electrocardiology
2008
41
6
553--6
Atrial fibrillation (AF) is the most common clinical cardiac arrhythmia and is usually treated with the electrical isolation of the pulmonary veins from the atria. However, it is estimated that about 30<prt>%</prt> of the patients undergoing this therapy will develop AF again. The purpose of this study was to test the dynamic changes of the spectra calculated in surface electrocardiograms (ECGs) before and after the ablation of the pulmonary veins. Surface ECGs of 14 patients with persistent AF undergoing this intervention were considered for this study. The QRS-T waves were subtracted from the ECGs using common spatial pattern, isolating the electrical activity of the atrium. The spectrum was then calculated and the main frequency peaks were identified. The smaller peaks with amplitude below 50<prt>%</prt> of the maximum were discarded. Eleven of the patients were followed up after the intervention for 1 to 6 months. Two of the patients developed AF again; the other 9 remained in sinus rhythm. For most of the patients, the spectrum showed more order after the intervention. However, the main frequency did not experience a significant decrease in average (5.1 Hz [+/-1.3] to 4.9 Hz [+/-1.0]). Interestingly, the increment or decrease of the main frequency did not correlate with the recurrence of AF or not.
Atrial Fibrillation,Atrial Fibrillation: diagnosis,Atrial Fibrillation: surgery,Catheter Ablation,Computer-Assisted,Computer-Assisted: methods,Diagnosis,Electrocardiography,Electrocardiography: methods,Female,Humans,Male,Middle Aged,Postoperative Care,Postoperative Care: methods,Preoperative Care,Preoperative Care: methods,Prognosis,Pulmonary Veins,Pulmonary Veins: surgery,Reproducibility of Results,Sensitivity and Specificity,Treatment Outcome
8.42
http://www.ncbi.nlm.nih.gov/pubmed/18817922
1532-8430
10.1016/j.jelectrocard.2008.06.018
IRomero
HKoch
EFleck
CKriatselis
article
Wubbeler2008
Evaluation of measurement uncertainty and its numerical calculation by a Monte Carlo method
Measurement Science and Technology
2008
19
8
084009
8.42,Unsicherheit
http://iopscience.iop.org/article/10.1088/0957-0233/19/8/084009
IOP Publishing
en
0957-0233
10.1088/0957-0233/19/8/084009
GWübbeler
MKrystek
CElster
article
Chunovkina2008
Analysis of key comparison data and laboratory biases
Metrologia
2008
45
2
211--216
8.42,KC
http://iopscience.iop.org/article/10.1088/0026-1394/45/2/010
IOP Publishing
en
0026-1394
10.1088/0026-1394/45/2/010
A GChunovkina
CElster
ILira
WWöger
article
Gross2008
Sensitivity analysis for indirect measurement in scatterometry and the reconstruction of periodic grating structures
Waves in Random and Complex Media
2008
18
1
129--149
We discuss numerical algorithms for the determination of periodic surface structures from light diffraction patterns. With decreasing details of lithography masks, increasing demands on metrology techniques arise. Scatterometry as a non-imaging indirect optical method is applied to simple periodic line structures in order to determine parameters like side-wall angles, heights, top and bottom widths and to evaluate the quality of the manufacturing process. The numerical simulation of diffraction is based on the finite element solution of the Helmholtz equation. The inverse problem seeks to reconstruct the grating geometry from measured diffraction patterns. Restricting the class of gratings and the set of measurements, this inverse problem can be reformulated as a non-linear operator equation in Euclidean spaces. The operator maps the grating parameters to special efficiencies of diffracted plane-wave modes. We employ a Gauß â€“Newton type iterative method to solve this operator equation. The reconstruction ...
8.41,Scatter-Inv,Scatterometrie
8.41,Scatter-Inv
http://www.tandfonline.com/doi/abs/10.1080/17455030701481823
Taylor <prt>&</prt> Francis Group
en
1745-5030
10.1080/17455030701481823
HGroß
ARathsfeld
article
Elster2008c
Uncertainty evaluation for dynamic measurements modelled by a linear time-invariant system
Metrologia
2008
45
4
464-473
dynamic measurement, digital filter, deconvolution, dynamic uncertainty
8.42,Dynamik, Unsicherheit
IOP Publishing
10.1088/0026-1394/45/4/013
CElster
ALink
article
Lira2007
Probabilistic and least-squares inference of the parameters of a straight-line model
Metrologia
2007
44
5
379--384
8.42,Bayes,Regression,Unsicherheit
http://iopscience.iop.org/article/10.1088/0026-1394/44/5/014
IOP Publishing
en
0026-1394
10.1088/0026-1394/44/5/014
ILira
CElster
WWöger
article
Link2007b
Modelling accelerometers for transient signals using calibration measurements upon sinusoidal excitation
Measurement
2007
40
9-10
928-935
A recently proposed accelerometer model is applied for determining the accelerometer's output to transient accelerations. The model consists of a linear, second-order differential equation with unknown coefficients. It is proposed to estimate these model parameters from sinusoidal calibration measurements, and an estimation procedure based on linear least-squares is presented. In addition, the uncertainties associated with the estimated parameters are determined utilizing a Monte Carlo simulation technique. The performance of the proposed modelling approach was tested by its application to calibration measurements of two back-to-back accelerometers (ENDEVCO type 2270 and Br<prt>ü</prt>el <prt>&</prt> Kjær type 8305). For each of the two accelerometers, the model was first estimated from sinusoidal calibration measurements and then used to predict the accelerometer's behaviour for two shock calibration measurements. Measured and predicted shock sensitivities were found consistent with differences below 1<prt>%</prt> in most cases which confirms the benefit of the proposed modelling approach.
IIR filter,Modelling,Shock excitation,Sinusoidal excitation,Uncertainty, dynamic measurement
8.42,Dynamik
10.1016/j.measurement.2006.10.011
ALink
ATäubner
WWabinski
TBruns
CElster
article
Link2007c
Comparing a template approach and complex bandpass filtering for single-trial analysis of auditory evoked M100
Biomedizinische Technik. Biomedical engineering
2007
52
1
106--10
Two methods for single-trial analysis were compared, an established parametric template approach and a recently proposed non-parametric method based on complex bandpass filtering. The comparison was carried out by means of pseudo-real simulations based on magnetoencephalography measurements of cortical responses to auditory signals. The comparison focused on amplitude and latency estimation of the M100 response. The results show that both methods are well suited for single-trial analysis of the auditory evoked M100. While both methods performed similarly with respect to latency estimation, the non-parametric approach was observed to be more robust for amplitude estimation. The non-parametric approach can thus be recommended as an additional valuable tool for single-trial analysis.
Algorithms,Auditory,Auditory: physiology,Computer-Assisted,Computer-Assisted: methods,Diagnosis, Computer-Assisted,Diagnosis, Computer-Assisted: methods,Electroencephalography,Electroencephalography: methods,Evoked Potentials, Auditory,Evoked Potentials, Auditory: physiology,Likelihood Functions,Reproducibility of Results,Sample Size,Sensitivity and Specificity,Signal Processing, Computer-Assisted
8.42, Gehirn
http://www.ncbi.nlm.nih.gov/pubmed/17313344
0013-5585
10.1515/BMT.2007.020
ALink
MBurghoff
ASalajegheh
DPoeppel
LTrahms
CElster
article
Seifert2007
Patient safety concept for multichannel transmit coils
Journal of magnetic resonance imaging : JMRI
2007
26
5
1315--21
PURPOSE: To propose and illustrate a safety concept for multichannel transmit coils in MRI based on finite-differences time-domain (FDTD) simulations and validated by measurements. MATERIALS AND METHODS: FDTD simulations of specific absorption rate (SAR) distributions in a cylindrical agarose phantom were carried out for various radio frequency (RF) driving conditions of a four-element coil array. Additionally, maps of transmit amplitude, signal phase, and temperature rise following RF heating were measured by MRI. RESULTS: Quantitative agreement was achieved between simulated and measured field distributions, thus validating the numerical modeling. When applying the same RF power to each element of the coil array but systematically varying the RF phase between its elements, the maximum of the SAR distribution was found to vary by a factor of about 15. CONCLUSION: Our results demonstrate that current RF safety approaches are inadequate to deal with the new challenge of multichannel transmit coils. We propose a new concept based on a systematic investigation of the parameter space for RF phases and amplitudes. In this way the driving conditions generating the highest local SAR values per unit power can be identified and appropriately considered in the RF safety concept of a given MRI system.
Biological,Body Burden,Computer Simulation,Electromagnetic Fields,Equipment Safety,Equipment Safety: methods,Germany,Humans,Magnetic Resonance Imaging,Magnetic Resonance Imaging: instrumentation,Models, Biological,Radiation Dosage,Radiation Monitoring,Radiation Monitoring: methods,Radiation Protection,Radiation Protection: methods,Relative Biological Effectiveness,Risk Assessment,Risk Assessment: methods,Risk Factors,Transducers,Whole-Body Counting,Whole-Body Counting: methods
8.42
http://www.ncbi.nlm.nih.gov/pubmed/17969165
1053-1807
10.1002/jmri.21149
FSeifert
GWübbeler
SJunge
BIttermann
HRinneberg
article
Wubbeler2007
Verification of humans using the electrocardiogram
Pattern Recognition Letters
2007
28
10
1172--1175
A feasibility study on the potential of the electrocardiogram (ECG) for biometrical applications is presented. A test set of 234 ECG recordings from 74 subjects was compiled emulating a realistic scenario for ECG biometrics by using short measurements of 10s length in combination with a practicable choice of ECG leads. The long-term stability of the individual ECG was investigated during time periods up to several years. Verification and identification was done by utilizing the heart vector and a simple distance measure. As a result, encouraging error rates were obtained; for verification, for instance, the achieved equal error rate was smaller than 3<prt>%</prt>.
Biometrics,Electrocardiogram (ECG),Identification,Verification
8.42
http://www.sciencedirect.com/science/article/pii/S0167865507000463
01678655
10.1016/j.patrec.2007.01.014
GWübbeler
MStavridis
DKreiseler
R-DBousseljot
CElster
article
Wubbeler2007a
Latency analysis of single auditory evoked M100 responses by spatio-temporal filtering
Physics in medicine and biology
2007
52
15
4383--92
Appropriate spatial filtering followed by temporal filtering is well suited for the single-trial analysis of multi-channel magnetoencephalogram or electroencephalogram recordings. This is demonstrated by the results of a single-trial latency analysis obtained for auditory evoked M100 responses from nine subjects using two different stimulation frequencies. Spatial filters were derived automatically from the data via noise-adjusted principle component analysis, and single-trial latencies were estimated from the signal phase after complex bandpass filtering. For each of the two stimulation frequencies, estimated single-trial latencies were consistent with results obtained from a standard approach using averaged evoked responses. The quality of the estimated single-trial latencies was additionally assessed by their ability to separate between the two different stimulation frequencies. As a result, more than 80<prt>%</prt> of the single trials can be classified correctly by their estimated latencies.
Acoustic Stimulation,Acoustic Stimulation: methods,Algorithms,Diagnosis, Computer-Assisted,Diagnosis, Computer-Assisted: methods,Evoked Potentials, Auditory,Evoked Potentials, Auditory: physiology,Humans,Magnetoencephalography,Magnetoencephalography: methods,Pitch Perception,Pitch Perception: physiology,Reaction Time,Reaction Time: physiology,Reproducibility of Results,Sensitivity and Specificity
8.42, Gehirn
http://www.ncbi.nlm.nih.gov/pubmed/17634639
0031-9155
10.1088/0031-9155/52/15/002
GWübbeler
ALink
MBurghoff
LTrahms
CElster
article
Bauer2007
Alternans and the influence of ionic channel modifications: Cardiac three-dimensional simulations and one-dimensional numerical bifurcation analysis
Chaos (Woodbury, N.Y.)
2007
17
1
015104
Cardiac propagation is investigated by simulations using a realistic three-dimensional (3D) geometry including muscle fiber orientation of the ventricles of a rabbit heart and the modified Beeler-Reuter ionic model. Electrical excitation is introduced by a periodic pacing of the lower septum. Depending on the pacing frequency, qualitatively different dynamics are observed, namely, normal heart beat, T-wave alternans, and 2:1 conduction block at small, intermediate, and large pacing frequencies, respectively. In a second step, we performed a numerical stability and bifurcation analysis of a pulse propagating in a one-dimensional (1D) ring of cardiac tissue. The precise onset of the alternans instability is obtained from computer-assisted linear stability analysis of the pulse and computation of the associated spectrum. The critical frequency at the onset of alternans and the profiles of the membrane potential agree well with the ones obtained in the 3D simulations. Next, we computed changes in the wave profiles and in the onset of alternans for the Beeler-Reuter model with modifications of the sodium, calcium, and potassium channels, respectively. For this purpose, we employ the method of numerical bifurcation and stability analysis. While blocking of calcium channels has a stabilizing effect, blocked sodium or potassium channels lead to the occurrence of alternans at lower pacing frequencies. The findings regarding channel blocking are verified within three-dimensional simulations. Altogether, we have found T-wave alternans and conduction block in 3D simulations of a realistic rabbit heart geometry. The onset of alternans has been analyzed by numerical bifurcation and stability analysis of 1D wave trains. By comparing the results of the two approaches, we find that alternans is not strongly influenced by ingredients such as 3D geometry and propagation anisotropy, but depends mostly on the frequency of pacing (frequency of subsequent action potentials). In addition, we have introduced numerical bifurcation and stability analysis as a tool into heart modeling and demonstrated its efficiency in scanning a large set of parameters in the case of models with reduced conductivity. Bifurcation analysis also provides an accurate test for analytical theories of alternans as is demonstrated for the case of the restitution hypothesis.
8.41,Action Potentials,Animals,Arrhythmias, Cardiac,Arrhythmias, Cardiac: physiopathology,Biological Clocks,Computer Simulation,Electric Countershock,Electric Countershock: methods,Heart Conduction System,Heart Conduction System: physiopathology,Heart Ventricles,Heart Ventricles: physiopathology,Humans,Imaging, Three-Dimensional,Ion Channel Gating,Ion Channels,Models, Cardiovascular,Myocardial Contraction,Oscillometry,Oscillometry: methods,Rabbits,Therapy, Computer-Assisted,Therapy, Computer-Assisted: methods
8.41
http://www.ncbi.nlm.nih.gov/pubmed/17411261
1054-1500
10.1063/1.2715668
SBauer
GRöder
MBär
article
Haberkorn2007
Analytical study of the magnetic field from extended sources in subcortical structures
2007
8.41
8.41
http://www.researchgate.net/publication/238648406<prt>\_</prt>Analytical<prt>\_</prt>study<prt>\_</prt>of<prt>\_</prt>the<prt>\_</prt>magnetic<prt>\_</prt>field<prt>\_</prt>from<prt>\_</prt>extended<prt>\_</prt>sources<prt>\_</prt>in<prt>\_</prt>subcortic
WHaberkorn
MBurghoff
article
Elster2007
Draft GUM Supplement 1 and Bayesian analysis
Metrologia
2007
44
3
L31--L32
8.42,Bayes,Unsicherheit
http://iopscience.iop.org/article/10.1088/0026-1394/44/3/N03
IOP Publishing
en
0026-1394
10.1088/0026-1394/44/3/N03
CElster
WWöger
M GCox
article
Elster2007b
Analysis of dynamic measurements and determination of time-dependent measurement uncertainty using a second-order model
Measurement Science and Technology
2007
18
12
3682-3687
dynamic measurement
8.42,Dynamik, Unsicherheit
IOP Publishing
en
10.1088/0957-0233/18/12/002
CElster
ALink
TBruns
article
Elster2007a
Calculation of uncertainty in the presence of prior knowledge
Metrologia
2007
44
2
111--116
8.42,Unsicherheit
http://iopscience.iop.org/article/10.1088/0026-1394/44/2/002
IOP Publishing
en
0026-1394
10.1088/0026-1394/44/2/002
CElster
article
Model2006
Improved transient hot strip sensor design by means of FEM simulations
THERMAL CONDUCTIVITY
2006
28
298--308
8.41
8.41
RModel
RStosch
UHammerschmidt
article
Nicola2006
Wave instability induced by nonlocal spatial coupling in a model of the light-sensitive Belousov-Zhabotinsky reaction
Physical review. E, Statistical, nonlinear, and soft matter physics
2006
73
6 Pt 2
066225
We study spatiotemporal patterns resulting from instabilities induced by nonlocal spatial coupling in the Oregonator model of the light-sensitive Belousov-Zhabotinsky reaction. In this system, nonlocal coupling can be externally imposed by means of an optical feedback loop which links the intensity of locally applied illumination with the activity in a certain vicinity of a particular point weighted by a given coupling function. This effect is included in the three-variable Oregonator model by an additional integral term in the photochemically induced bromide flow. A linear stability analysis of this modified Oregonator model predicts that wave and Turing instabilities of the homogeneous steady state can be induced for experimentally realistic parameter values. In particular, we find that a long-range inhibition in the optical feedback leads to a Turing instability, while a long-range activation induces wave patterns. Using a weakly nonlinear analysis, we derive amplitude equations for the wave instability which are valid close to the instability threshold. Therein, we find that the wave instability occurs supercritically or subcritically and that traveling waves are preferred over standing waves. The results of the theoretical analysis are in good agreement with numerical simulations of the model near the wave instability threshold. For larger distances from threshold, a secondary breathing instability is found for traveling waves.
8.41
8.41
http://www.ncbi.nlm.nih.gov/pubmed/16906964
1539-3755
10.1103/PhysRevE.73.066225
E MNicola
MBär
HEngel
article
Peruani2006
Nonequilibrium clustering of self-propelled rods
Physical Review E
2006
74
3
030904
8.41,8.43
8.41,8.43
http://link.aps.org/doi/10.1103/PhysRevE.74.030904
1539-3755
10.1103/PhysRevE.74.030904
FPeruani
ADeutsch
MBär
article
Martens2006
Final report on the key comparison EUROMET.AUV.V-K1
Metrologia
2006
43
1A
09002-09002
8.42,Dynamik,KC
IOP Publishing
10.1088/0026-1394/43/1A/09002
H-Jvon Martens
CElster
ALink
ATäubner
TBruns
article
Link2006a
Calibration of accelerometers: determination of amplitude and phase response upon shock excitation
Measurement Science and Technology
2006
17
7
1888-1894
8.42,Dynamik
IOP Publishing
en
10.1088/0957-0233/17/7/030
ALink
ATäubner
WWabinski
TBruns
CElster
article
Link2006
Modellierung von Kraft- und Beschleunigungsaufnehmern für die Stoßkalibrierung (Modelling Force and Acceleration Transducers for Shock Calibrations)
tm - Technisches Messen
2006
73
12
675-683
8.42,Dynamik
10.1524/teme.2006.73.12.675
ALink
MKobusch
TBruns
CElster
article
Leistner2006
Tonic neuronal activation during simple and complex finger movements analyzed by DC-magnetoencephalography
Neuroscience letters
2006
394
1
42--7
Functional neuroimaging techniques map neuronal activation indirectly via local concomitant cortical vascular/metabolic changes. In a complementary approach, DC-magnetoencephalography measures neuronal activation dynamics directly, notably in a time range of the slow vascular/metabolic response. Here, using this technique neuronal activation dynamics and patterns for simple and complex finger movements are characterized intraindividually: in 6/6 right-handed subjects contralateral prolonged (30 s each) complex self-paced sequential finger movements revealed stronger field amplitudes over the pericentral sensorimotor cortex than simple movements. A consistent lateralization for contralateral versus ipsilateral finger movements was not found (4/6). A subsequent sensory paradigm focused on somatosensory afferences during the motor tasks and the reliability of the measuring technique. In all six subjects stable sustained neuronal activation during electrical median nerve stimulation was recorded. These neuronal quasi-tonic activation characteristics provide a new non-invasive neurophysiological measure to interpret signals mapped by functional neuroimaging techniques.
Adult,Brain Mapping,Evoked Potentials, Somatosensory,Evoked Potentials, Somatosensory: physiology,Evoked Potentials, Somatosensory: radiation effect,Female,Fingers,Fingers: physiology,Functional Laterality,Functional Laterality: physiology,Humans,Magnetoencephalography,Male,Motor Cortex,Motor Cortex: physiology,Motor Cortex: radiation effects,Movement,Movement: physiology,Movement: radiation effects,Psychomotor Performance,Psychomotor Performance: physiology,Psychomotor Performance: radiation effects,Somatosensory,Somatosensory: physiology,Somatosensory: radiation effect
8.42, Gehirn
http://www.sciencedirect.com/science/article/pii/S0304394005011523
0304-3940
10.1016/j.neulet.2005.10.004
SLeistner
GWübbeler
LTrahms
GCurio
B MMackert
article
Wei2006
Nucleation of spiral wave patterns at surface defects
Physical review. E, Statistical, nonlinear, and soft matter physics
2006
73
1 Pt 2
016210
The nucleation of spiral waves at a surface defect during catalytic CO oxidation on Pt(110) has been studied with a low energy electron microscope system. It is found that reaction fronts originate from a boundary layer between the defect and the surrounding Pt(110) area. The findings are corroborated by numerical simulations within a realistic reaction-diffusion model of the surface reaction.
8.41
8.41
http://www.ncbi.nlm.nih.gov/pubmed/16486261
1539-3755
10.1103/PhysRevE.73.016210
HWei
GLilienkamp
JDavidsen
MBär
RImbihl
article
Schulz2006
Traceable multiple sensor system for measuring curved surface profiles with high accuracy and high lateral resolution
Optical Engineering
2006
45
6
8.42,Form,SimOpt
10.1117/1.2208568
MSchulz
CElster
article
Borner2006
A generalized discrete model linking rippling pattern formation and individual cell reversal statistics in colonies of myxobacteria
Physical biology
2006
3
2
138--46
Self-organization processes in multicellular aggregates of bacteria and amoebae offer fascinating insights into the evolution of cooperation and differentiation of cells. During myxobacterial development a variety of spatio-temporal patterns emerges such as counterpropagating waves of cell density that are known as rippling. Recently, several models have been introduced that qualitatively reproduce these patterns. All models include active motion and a collision-triggered reversal of individual bacteria. Here, we present a systematic study of a generalized discrete model that is based on similar assumptions as the continuous model by Igoshin et al (2001 Proc. Natl Acad. Sci. USA 98 14913). We find counterpropagating as well as unidirectional rippling waves in extended regions of the parameter space. If the interaction strength and the degree of cooperativity are large enough, rippling patterns appear even in the absence of a refractory period. We show for the first time that the experimentally observed double peak in the reversal statistics of bacteria in rippling colonies (Welch and Kaiser 2001 Proc. Natl Acad. Sci. USA 98 14907) can be reproduced in simulations of counterpropagating rippling waves which are dominant in experiments. In addition, the reversal statistics in the pre-rippling phase is correctly reproduced.
8.41,Biological,Biological Evolution,Computer Simulation,Linear Models,Models, Biological,Myxococcales,Myxococcales: growth <prt>&</prt> development
8.41
http://www.ncbi.nlm.nih.gov/pubmed/16829700
1478-3975
10.1088/1478-3975/3/2/006
UBörner
ADeutsch
MBär
article
Haberkorn2006
Pseudo current density maps of electrophysiological heart, nerve or brain function and their physical basis
Biomagnetic research and technology
2006
4
1
5
BACKGROUND: In recent years the visualization of biomagnetic measurement data by so-called pseudo current density maps or Hosaka-Cohen (HC) transformations became popular. METHODS: The physical basis of these intuitive maps is clarified by means of analytically solvable problems. RESULTS: Examples in magnetocardiography, magnetoencephalography and magnetoneurography demonstrate the usefulness of this method. CONCLUSION: Hardware realizations of the HC-transformation and some similar transformations are discussed which could advantageously support cross-platform comparability of biomagnetic measurements.
8.41
8.41
http://www.biomagres.com/content/4/1/5
BioMed Central Ltd
en
1477-044X
10.1186/1477-044X-4-5
WHaberkorn
USteinhoff
MBurghoff
OKosch
AMorguet
HKoch
article
Hammerschmidt2006a
JANUS: High Temperature Transient Hot Bridge Sensor
THERMAL CONDUCTIVITY
2006
28
288--297
8.41
8.41
UHammerschmidt
VMeier
RModel
article
Gross2006
Mathematical modelling of indirect measurements in scatterometry
Measurement
2006
39
9
782--794
8.41
8.41, Scatter-Inv
http://www.researchgate.net/publication/223944217<prt>\_</prt>Mathematical<prt>\_</prt>modelling<prt>\_</prt>of<prt>\_</prt>indirect<prt>\_</prt>measurements<prt>\_</prt>in<prt>\_</prt>scatterometry
02632241
10.1016/j.measurement.2006.04.009
HGroß
RModel
MBär
MWurm
BBodermann
ARathsfeld
article
Elster2006
Coupled distance sensor systems for high-accuracy topography measurement: Accounting for scanning stage and systematic sensor errors
Precision Engineering
2006
30
1
32--38
Scanning topography measurements using systems of coupled distance sensors suffer from the presence of scanning stage and systematic sensor errors. While scanning stage errors can be estimated for suitably-designed sensor systems, it is usually not possible to simultaneously estimate both scanning stage and systematic sensor errors. Additional angular scanning stage measurements can solve this problem, and potentials and limitations of such a proceeding will be assessed. It is shown that perfect topography reconstruction can be achieved in the presence of systematic sensor and certain scanning stage errors provided that the measurements are noise-free and no further systematic errors emerge. In general, the topography is reconstructed by the application of least-squares, and the uncertainty associated with the reconstructed topography is derived. Resulting topography accuracies are evaluated for different noise levels of the distance sensor and angular scanning stage measurements, and practical considerations are discussed. The gain in accuracy due to accounting for scanning stage and systematic sensor errors can be large, and high accuracies can be reached.
Angular measurement,Distance sensor,High accuracy,High resolution,Least-squares,Topography,Uncertainty
8.42,Form,SimOpt
http://www.sciencedirect.com/science/article/pii/S0141635905000504
01416359
10.1016/j.precisioneng.2005.04.001
CElster
IWeingärtner
MSchulz
article
Geckeler2006
Calibration of angle encoders using transfer functions
Measurement Science and Technology
2006
17
10
2811--2818
8.42
http://www.researchgate.net/publication/231067471<prt>\_</prt>Calibration<prt>\_</prt>of<prt>\_</prt>angle<prt>\_</prt>encoders<prt>\_</prt>using<prt>\_</prt>transfer<prt>\_</prt>functions
0957-0233
10.1088/0957-0233/17/10/036
R DGeckeler
AFricke
CElster
article
Model2005b
An identification procedure for thermal transport properties of layered solids by means of transient measurements
Thermal Conductivity 26/Thermal Expansion 14
2005
346--357
8.41, Flow
RModel
UHammerschmidt
article
Model2005
Thermal Transport Properties of Layered Materials: Identification by a New Numerical Algorithm for Transient Measurements
International Journal of Thermophysics
2005
26
1
165--178
8.41
8.41, Flow
http://www.researchgate.net/publication/226424470<prt>\_</prt>Thermal<prt>\_</prt>Transport<prt>\_</prt>Properties<prt>\_</prt>of<prt>\_</prt>Layered<prt>\_</prt>Materials<prt>\_</prt>Identification<prt>\_</prt>by<prt>\_</prt>a<prt>\_</prt>New<prt>\_</prt
0195-928X
10.1007/s10765-005-2363-1
RModel
article
Nicolaus2005
Diameter Determination of Avogadro Spheres #1 and #2
IEEE Transactions on Instrumentation and Measurement
2005
54
2
872--876
Absolute density,Arm,Avogadro constant,Avogadro spheres,Avogadro's constant,Crystalline materials,Density measurement,Germany,IMGC,Italy,Laser tuning,Optical fiber testing,Optical interferometry,Performance evaluation,Physikalisch-Technische Bundesanstalt,Silicon,Surfaces,Volume measurement,absolute density,constants,diameter determination,diameter measurements,mass measurement,silicon crystal,spatial distribution,spheres interferometer,spherical beams,spherical reference plates,volume,volume measurement
8.42
http://ieeexplore.ieee.org/articleDetails.jsp?arnumber=1408309
IEEE
English
0018-9456
10.1109/TIM.2005.843527
R ANicolaus
CElster
article
VonMartens2005
Fortschritte bei Schwingungs- und Stoßkalibrierung mittels Laserinterferometrie
Technisches Messen
2005
72
141-152
8.42,Dynamik
10.1524/teme.72.3.141.60281
H-Jvon Martens
WWabinski
ALink
H-JSchlaak
ATäubner
UGöbel
article
Link2005
Identifikation von Beschleunigungsaufnehmern mit hochintensiven Stößen
tm - Technisches Messen
2005
72
3-2005
153-160
8.42,Dynamik
10.1524/teme.72.3.153.60277
ALink
WWabinski
H-Jvon Martens
article
John2005
Self-propelled running droplets on solid substrates driven by chemical reactions
Eur. Phys. J. E, Soft matter
2005
18
2
183--99
We study chemically driven running droplets on a partially wetting solid substrate by means of coupled evolution equations for the thickness profile of the droplets and the density profile of an adsorbate layer. Two models are introduced corresponding to two qualitatively different types of experiments described in the literature. In both cases an adsorption or desorption reaction underneath the droplets induces a wettability gradient on the substrate and provides the driving force for droplet motion. The difference lies in the behavior of the substrate behind the droplet. In case I the substrate is irreversibly changed whereas in case II it recovers allowing for a periodic droplet movement (as long as the overall system stays far away from equilibrium). Both models allow for a non-saturated and a saturated regime of droplet movement depending on the ratio of the viscous and reactive time scales. In contrast to model I, model II allows for sitting drops at high reaction rate and zero diffusion along the substrate. The transition from running to sitting drops in model II occurs via a super- or subcritical drift-pitchfork bifurcation and may be strongly hysteretic implying a coexistence region of running and sitting drops.
8.41
8.41,
http://www.researchgate.net/publication/7538520<prt>\_</prt>Self-propelled<prt>\_</prt>running<prt>\_</prt>droplets<prt>\_</prt>on<prt>\_</prt>solid<prt>\_</prt>substrates<prt>\_</prt>driven<prt>\_</prt>by<prt>\_</prt>chemical<prt>\_</prt>reactions
1292-8941
10.1140/epje/i2005-10039-1
KJohn
MBär
UThiele
article
Schmitz2005
Magnetocardiography in a fetus with Long-QT syndrome
Circulation
2005
112
e68--e69
8.42
10.1161/CIRCULATIONAHA.104.494104
LSchmitz
MBurghoff
article
Bousseljot2005
Telemetric ECG evaluation using Einthoven-Leads
Comput. Cardiol.
2005
57--60
Biomedical electrodes,CSE test data set,Cardiology,Databases,ECG database,Einthoven-leads,Electrocardiography,Medical diagnostic imaging,Myocardium,Pressure measurement,Sensitivity and specificity,Telemetry,Testing,biomedical equipment,biomedical telemetry,blind test,conduction disturbance,cross correlation method,diseases,electrocardiography,ischaemic diseases,medical computing,medical information systems,medical leads,myocardial infarction,patient diagnosis,probability,probability distributions,telemetric 12-channel ECG evaluation,telemetric 3-channel ECG evaluation,ventricular hypertrophy
8.42
http://ieeexplore.ieee.org/articleDetails.jsp?arnumber=1588032
IEEE
Computers in Cardiology, 2005
English
0-7803-9337-6
10.1109/CIC.2005.1588032
RBousseljot
DKreiseler
article
Burghoff2005
A template-free approach for determining the latency of single events of auditory evoked M100
Physics in medicine and biology
2005
50
3
N43--8
The phase of the complex output of a narrow band Gaussian filter is taken to define the latency of the auditory evoked response M100 recorded by magnetoencephalography. It is demonstrated that this definition is consistent with the conventional peak latency. Moreover, it provides a tool for reducing the number of averages needed for a reliable estimation of the latency. Single-event latencies obtained by this procedure can be used to improve the signal quality of the conventional average by latency adjusted averaging.
Evoked Potentials, Auditory,Magnetoencephalography,Magnetoencephalography: methods,Models, Theoretical,Normal Distribution,Time Factors
8.42, Gehirn
http://www.ncbi.nlm.nih.gov/pubmed/15773733
0031-9155
10.1088/0031-9155/50/3/N04
MBurghoff
ALink
ASalajegheh
CElster
DPoeppel
LTrahms
article
Burghoff2005a
Visualization of action currents propagation in peripheral nerves from the biomagnetic field
Biomed. Tech.
2005
50
1
179--180
8.41
8.41, BioMed
MBurghoff
B MMackert
WHaberkorn
article
John2005b
Travelling lipid domains in a dynamic model for protein-induced pattern formation in biomembranes
Physical biology
2005
2
2
123--32
Cell membranes are composed of a mixture of lipids. Many biological processes require the formation of spatial domains in the lipid distribution of the plasma membrane. We have developed a mathematical model that describes the dynamic spatial distribution of acidic lipids in response to the presence of GMC proteins and regulating enzymes. The model encompasses diffusion of lipids and GMC proteins, electrostatic attraction between acidic lipids and GMC proteins as well as the kinetics of membrane attachment/detachment of GMC proteins. If the lipid-protein interaction is strong enough, phase separation occurs in the membrane as a result of free energy minimization and protein/lipid domains are formed. The picture is changed if a constant activity of enzymes is included into the model. We chose the myristoyl-electrostatic switch as a regulatory module. It consists of a protein kinase C that phosphorylates and removes the GMC proteins from the membrane and a phosphatase that dephosphorylates the proteins and enables them to rebind to the membrane. For sufficiently high enzymatic activity, the phase separation is replaced by travelling domains of acidic lipids and proteins. The latter active process is typical for nonequilibrium systems. It allows for a faster restructuring and polarization of the membrane since it acts on a larger length scale than the passive phase separation. The travelling domains can be pinned by spatial gradients in the activity; thus the membrane is able to detect spatial clues and can adapt its polarity dynamically to changes in the environment.
8.41,Biophysics,Biophysics: methods,Cell Membrane,Cell Membrane: metabolism,Chemical,Diffusion,Kinetics,Lipids,Lipids: chemistry,Membrane Lipids,Membrane Lipids: chemistry,Models, Chemical,Models, Statistical,Models, Theoretical,Phosphorylation,Protein Biosynthesis,Protein Interaction Mapping,Protein Kinase C,Protein Kinase C: metabolism,Protein Structure, Tertiary,Statistical,Tertiary,Theoretical,Thermodynamics
8.41
http://www.ncbi.nlm.nih.gov/pubmed/16204864
1478-3975
10.1088/1478-3975/2/2/005
KJohn
MBär
article
John2005a
Alternative mechanisms of structuring biomembranes: self-assembly versus self-organization
Physical review letters
2005
95
19
198101
We study two mechanisms for the formation of protein patterns near membranes of living cells by mathematical modelling. Self-assembly of protein domains by electrostatic lipid-protein interactions is contrasted with self-organization due to a nonequilibrium biochemical reaction cycle of proteins near the membrane. While both processes lead eventually to quite similar patterns, their evolution occurs on very different length and time scales. Self-assembly produces periodic protein patterns on a spatial scale below 0.1 microm in a few seconds followed by extremely slow coarsening, whereas self-organization results in a pattern wavelength comparable to the typical cell size of 100 microm within a few minutes suggesting different biological functions for the two processes.
8.41,Algorithms,Cell Physiological Phenomena,Membrane Proteins,Membrane Proteins: chemistry,Membranes,Membranes: chemistry,Models, Statistical,Particle Size,Phosphorylation,Statistical
8.41
http://www.ncbi.nlm.nih.gov/pubmed/16384028
0031-9007
10.1103/PhysRevLett.95.198101
KJohn
MBär
article
Elster2005a
Quantitative magnetic resonance spectroscopy: semi-parametric modeling and determination of uncertainties
Magnetic resonance in medicine
2005
53
6
1288--96
A semi-parametric approach for the quantitative analysis of magnetic resonance (MR) spectra is proposed and an uncertainty analysis is given. Single resonances are described by parametric models or by parametrized in vitro spectra and the baseline is determined nonparametrically by regularization. By viewing baseline estimation in a reproducing kernel Hilbert space, an explicit parametric solution for the baseline is derived. A Bayesian point of view is adopted to derive uncertainties, and the many parameters associated with the baseline solution are treated as nuisance parameters. The derived uncertainties formally reduce to Cram<prt>é</prt>r-Rao lower bounds for the parametric part of the model in the case of a vanishing baseline. The proposed uncertainty calculation was applied to simulated and measured MR spectra and the results were compared to Cram<prt>é</prt>r-Rao lower bounds derived after the nonparametrically estimated baselines were subtracted from the spectra. In particular, for high SNR and strong baseline contributions the proposed procedure yields a more appropriate characterization of the accuracy of parameter estimates than Cr<prt>é</prt>mer-Rao lower bounds, which tend to overestimate accuracy.
Bayes Theorem,Brain Chemistry,Computer Simulation,Computer-Assisted,Humans,Least-Squares Analysis,Magnetic Resonance Spectroscopy,Magnetic Resonance Spectroscopy: methods,Models, Statistical,Regression,Signal Processing, Computer-Assisted,Statistical
8.42, Unsicherheit, in-vivo
http://www.ncbi.nlm.nih.gov/pubmed/15906296
0740-3194
10.1002/mrm.20500
CElster
FSchubert
ALink
MWalzel
FSeifert
HRinneberg
article
Elster2005
Analysis of Key Comparison Data: Unstable Travelling Standards
Measurement Techniques
2005
48
9
883--893
8.42,KC
http://link.springer.com/10.1007/s11018-005-0239-1
0543-1972
10.1007/s11018-005-0239-1
CElster
WWöger
M GCox
article
Gargioni2005
A simple method for measuring thoron spatial distributions
Radiation protection dosimetry
2005
113
3
321--5
A simple but effective method that allows the measurement of the 220Rn spatial distribution in working or living environments using a solid-state detector is presented in this paper. The method is based on measurements of the alpha particles emitted by 216Po (the first 220Rn progeny) directly deposited on the detector surface at different distances from a 220Rn exhalation source. The validity of the method is shown by comparing the results of an experiment, where the 220Rn activity concentration is measured under conditions of diffusion at constant temperature, with finite-element calculations.
8.41,Air Pollution, Indoor,Air Pollution, Indoor: analysis,Algorithms,Alpha Particles,Equipment Design,Equipment Failure Analysis,Occupational Exposure,Occupational Exposure: analysis,Radiation Dosage,Radiation Monitoring,Radiation Monitoring: instrumentation,Radiation Monitoring: methods,Radon,Radon: analysis,Risk Assessment,Risk Assessment: methods,Risk Factors
8.41,
http://rpd.oxfordjournals.org/content/113/3/321
0144-8420
10.1093/rpd/nch467
EGargioni
RModel