This file was created by the TYPO3 extension bib --- Timezone: CEST Creation date: 2024-04-23 Creation time: 11-57-23 --- Number of references 397 article BocklerdMSSBKBWTTWGSG2024 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 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 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 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 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 Metrologia 2023 9 22 60 5 054004 8.4,8.42,Messunsicherheit 10.1088/1681-7575/acf3eb KKlauenberg JGreenwood GFoyer article KastnerMHMPCWHRE2023 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 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 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 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 Metrologia 2023 7 17 8.4,8.41,Flow, UQ accepted DOI 10.1088/1681-7575/ace7d6 AndreasWeissenbrunner Ann-KathrinEkat MartinStraka SonjaSchmelter article MarschallWSE2023 Metrologia 2023 7 4 60 4 8.4,8.42,LargeScaleDataAna,ML 10.1088/1681-7575/ace3c2 MMarschall GWübbeler FSchmähling CElster article BrahmaKMSK2023 Medical Physics 2023 6 27 8.4,8.42,ML,Messunsicherheit,LargeScaleDataAna 10.1002/mp.16543 SBrahma CKolbitsch JMartin TSchäffter AKofler article MarschallWBE2023 Metrologia 2023 6 26 8.4,8.42,KC,Messunsicherheit accepted 10.1088/1681-7575/ace18f MMarschall GWübbeler MBorys CElster article KokDWE2023 Metrologia 2023 5 19 8.4,8.42,Messunsicherheit,Form accepted 10.1088/1681-7575/acd6fd GKok v MDijk GWübbeler CElster article StrodthoffMNASGKHDLBS2023 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 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 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 Computational Statistics 2023 3 16 8.4,8.42,ML,LargeScaleDataAna 10.1007/s00180-023-01345-5 MMarschall GWübbeler FSchmähling CElster article WebnerPKS2023 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 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 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 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 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 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 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 2022 12 20 8.4, 8.41, flow TU Berlin https://doi.org/10.14279/depositonce-16659 MarcOlbrich article MartinE2021_2 Neural Processing Letters 2022 11 1 8.4,8.42,ML 1573-773X 10.1007/s11063-022-11066-3 JMartin CElster conference SchmelterKOB2022 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 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 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 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 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 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 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 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 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 Applied Intelligence 2022 8 9 8.4,8.42,ML 10.1007/s10489-022-03908-3 FrankoSchmähling JörgMartin ClemensElster article StrakaWKHS2022 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 Machine Learning: Science and Technology 2022 6 17 8.4,8.42,ML accepted 10.1088/2632-2153/ac7a03 NAmanova JMartin CElster article WorlitzerJGBHEAB2022 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 Metrology 2022 6 12 2 311--319 8.4,8.42,Messunsicherheit,Form 10.3390/metrology2020019 GKok GWübbeler CElster phdthesis Farchmin2022 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 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 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 Statistics and Computing 2022 3 12 32 2 27 8.4,8.42 10.1007/s11222-022-10087-1 MEigel RGruhlke MMarschall article WubbelerMKHHE2022 Metrology 2022 3 1 2 1 114--127 8.42,8.4,Form 10.3390/metrology2010008 GWübbeler MMarschall KKniel DHeißelmann FHärtig CElster article PolanskyS2022 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 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 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 Metrologia 2022 2 1 59 1 015004 8.4,8.42,Messunsicherheit 10.1088/1681-7575/ac3920 MMarschall GWübbeler CElster article GruberDSEE2022 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 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 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 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 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 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 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 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 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 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 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 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 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 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 2021 12 7 publiziert 8.4,8.42,Messunsicherheit,Regression,Fingerprinting,LargeScaleDataAna TU Berlin PhD Thesis 10.14279/depositonce-12455 SMetzner article WilczekHB2021 Physik Journal 2021 12 1 20 12 35 8.4,8.43 MWilczek SHeidenreich MBär article HoffmannFE2021_2 tm - Technisches Messen 2021 11 20 publiziert 8.4,8.42,Form,ML 10.1515/teme-2021-0103 LHoffmann IFortmeier CElster article WorlitzerABSBH2021 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 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 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 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 Metrologia 2021 10 12 58 6 064001 8.4,8.42,Form 10.1088/1681-7575/ac2724 MarkusFischedick ManuelStavridis GuidoBartl ClemensElster article KnotekSO2021 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 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 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 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 Measurement Science and Technology 2021 4 30 32 7 5005 8.4,8.42,Messunsicherheit 10.1088/1361-6501/abe2bd JMartin CElster article AndrleFHHSS2021 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 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 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 Statistics and Public Policy 2021 3 10 8.4,8.42,Stichprobenverf 10.1080/2330443X.2021.1900762 KKlauenberg C AMüller CElster article WorlitzerABSB2021 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 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 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 Int J Mol Sci . 2021 2 10 22 4 1753 8.4,8.41,Cyto 10.3390/ijms22041753 KSmuda JGienger PHönicke JNeukammer article SchmelterKOFB2021 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 Metrologia 2021 1 7 58 1 014002 online 8.4,8.42,Regression,LargeScaleDataAna accepted 10.1088/1681-7575/abc97b GWübbeler CElster article SchmidtFSSLS2021 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 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 &amp; 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 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 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 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 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 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 Appl Intell 2020 10 30 publiziert 8.4,8.42,ML 10.1007/s10489-020-01925-8 JMartin CElster article WubbelerME2020 Metrologia 2020 10 21 57 6 065010 8.4,8.42,Unsicherheit 10.1088/1681-7575/aba3b8 GWübbeler MMarschall CElster article OlbrichSBSOS2020 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 2020 10 7 publiziert 8.4,8.42,ML http://dx.doi.org/10.14279/depositonce-10552 TU Berlin PhD Thesis TKretz article HoffmannE2020 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 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 Statistical Methods & Applications 2020 8 25 1613-981X 8.4,8.42,Unsicherheit 10.1007/s10260-020-00545-3 JMartin CElster article DemeyerFE2020 Metrologia 2020 8 18 8.4,8.42,Unsicherheit 10.1088/1681-7575/abb065 SDemeyer NFischer CElster article ElsterK2020 Statistics & Probability Letters 2020 6 20 165 108851 8.4,8.42,Stichprobenverf /10.1016/j.spl.2020.108851 CElster KKlauenberg article ReinkenNHSBKA2020 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 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 Physics in Medicine & Biology 2020 4 23 65 8 085017 8.4,8.42 10.1088/1361-6560/ab7b2e MAnton W J HVeldkamp IHernandez-Giron CElster article KretzMSE2020 IEEE Transactions on Biomedical Engineering 2020 4 14 publiziert 8.4,8.42,ML 10.1109/TBME.2020.2983539 TKretz K-RMüller TSchäffter CElster article BartlEMSVW2020 Measurement Science and Technology 2020 4 3 31 6 8.4,8.42,Unsicherheit,Regression 10.1088/1361-6501/ab7359 GBartl CElster JMartin RSchödel MVoigt AWalkov article BeaerIGKHBA2020 Commun Phys 2020 4 3 3 66 8.4,ActFluid 10.1038/s42005-020-0327-1 ABe´er BIlkanaiv RGross D BKearns SHeidenreich MBär GAriel article MartinE2020 Neurocomputing 2020 3 21 382 80--86 publiziert 8.4,8.42,ML 10.1016/j.neucom.2019.11.052 JMartin CElster conference CasforZapataFPNSHLKS2020 2020 3 20 11325 8.4,8.43,UQ SPIE Proc. of SPIE San Jose, USA Metrology, Inspection, and Process Control for Microlithography XXXIV 20.03.2020 10.1117/12.2552037 M.Casfor Zapata N.Farchmin M.Pflüger K.Nikolaev V.Soltwisch S.Heidenreich C.Laube M.Kolbe F.Scholze article SchmelterOSB2020 Flow Measurement and Instrumentation 2020 3 10 73 101722 8.4,8.41,Flow 10.1016/j.flowmeasinst.2020.101722 SSchmelter MOlbrich ESchmeyer MBär article SchenkerSST2020 Opt. Eng. 2020 3 3 59 3 034101 8.4,8.42,Form 10.1117/1.OE.59.3.034101 MSchenker MStavridis MSchulz RTutsch article BarGHP2020 Annual Review of Condensed Matter Physics 2020 3 1 11 441--466 8.4,,ActFluid 10.1146/annurev-conmatphys-031119-050611 MBär RGroßmann SHeidenreich FPeruani article WubbelerE2020 Metrologia 2020 1 23 57 1 8.4,8.42,Unsicherheit 10.1088/1681-7575/ab50d6 GWübbeler CElster article FortmeierSLMSHBBKSE2019 Journal of the European Optical Society-Rapid Publications 2020 1 8 16 2 8.4,8.42,Form 10.1186/s41476-019-0124-1 InesFortmeier ReykoSchachtschneider VitLedl OndrejMatousek JensSiepmann AntoniaHarsch RolfBeisswanger YouichiBitou YohanKondo MichaelSchulz ClemensElster article LehnertKWCSE2019 SIAM J. Imaging Sci. 2019 12 12 12 4 2035--2062 8.4,8.42,Regression,LargeScaleDataAna 10.1137/19M1246274 JudithLehnert ChristophKolbitsch GerdWübbeler AmedeoChiribiri TobiasSchäffter ClemensElster article KlauenbergE2019 tm - Technisches Messen 2019 11 7 86 12 773--783 8.4,8.42,Stichprobenverf 10.1515/teme-2019-0148 KKlauenberg CElster article KlauenbergWE2019 Measurement Science Review 2019 9 30 19 5 204--208 8.4,8.42,Unsicherheit 10.2478/msr-2019-0026 KKlauenberg GWübbeler CElster article GiengerGOBN2019 Biomedical Optics Express 2019 9 1 10 9 4531 -- 4550 8.4,8.41,Cyto 10.1364/BOE.10.004531 JGienger HGross VOst MBär JNeukammer article MetznerWE2018 AStA Adv Stat Anal 2019 8 29 103 3 333--355 8.4,8.42,Messunsicherheit,Regression,Fingerprinting,LargeScaleDataAna 10.1007/s10182-018-00334-0 SMetzner GWübbeler CElster article SchmelterOSB2019 Proceedings of the 18th International Flow Measurement Conference FLOMEKO 2019 2019 7 1 8.4,8.41,Flow SSchmelter MOlbrich ESchmeyer MBär article OlbrichSBSOS2019 Proceedings of the 18th International Flow Measurement Conference FLOMEKO 2019 2019 7 1 8.4,8.41,Flow MOlbrich ESchmeyer MBär MSieber KOberleithner SSchmelter article KretzASE2019 Physica Medica 2019 5 20 62 120--128 8.4,8.42 10.1016/j.ejmp.2019.05.008 TKretz MAnton TSchäffter CElster article KulawiakLBE2019 PLoS One 2019 5 14 14 8 8.4,8.41 10.1101/638312 D AKulawiak JLöber MBär HEngel article RiazySOAvNS2019 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 JSchulz-Menger article GiengerSMBN2019 Scientific Reports 2019 3 15 9 8.4,8.41,Cyto 10.1038/s41598-019-38767-5 JGienger KSmuda RMüller MBär JNeukammer article AlvesdBd2019 Front. Physiol. 2019 3 14 10 177 8.4,8.41 10.3389/fphys.2019.00177 J. RAlves R. A. Bde Queiroz MBär R. Wdos Santos article SchachtschneiderSFSE2019 Journal of Sensors and Sensor Systems 2019 2 27 8 1 105--110 8.4, 8.42, Form 10.5194/jsss-8-105-2019 RSchachtschneider MStavridis IFortmeier MSchulz CElster article MartinBE2019 Measurement Science and Technology 2019 2 21 30 045012 8.4,8.42,Unsicherheit,Regression 10.1088/1361-6501/ab094b JMartin GBartl CElster article ReinkenHBK2019 New Journal of Physics 2019 1 31 21 1 013037 8.4,8.43 10.1088%2F1367-2630%2Faaff09 HReinken SHeidenreich MBär S. H. LKlapp article KulawiakLBE2018 Journal of Physics D: Applied Physics 2019 1 1 52 1 014004 8.4,8.41 10.1088/1361-6463/aae41d D AKulawiak JLöber MBär HEngel article OlbrichSROBS2018 J. 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Series 2018 11 1 1065 9 092015 8.4,8.41,Flow 10.1088/1742-6596/1065/9/092015 MOlbrich ESchmeyer LRiazy KOberleithner MBär SSchmelter article SchmelterOSB2018 Proceedings of the North Sea Flow Measurement Workshop 2018 2018 11 1 8.4,8.41,Flow SSchmelter MOlbrich ESchmeyer MBär article HeidenreichGB2018 Metrologia 2018 10 19 55 6 201 8.4,8.43, UQ 10.1088/1681-7575/aae41c SHeidenreich HGross MBär article LehnertWKCCESSE2018 Physics in Medicine & Biology 2018 10 10 63 215017 8.4, 8.42,Regression,LargeScaleDataAna 10.1088/1361-6560/aae758 JLehnert GWübbeler CKolbitsch AChiribiri LCoquelin GEbrard NSmith TSchäffter CElster article ArielSRHBB2018 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 Metrologia 2018 9 7 55 5 722 8.4,8.42,KC 10.1088/1681-7575/aadb6b GWübbeler HBettin FHärtig CElster article KastnerSHUHKPRWE2018 Optics Express 2018 7 26 14 18115--18124 8.4,8.42,LargeScaleDataAna 10.1364/OE.26.018115 BKästner FSchmähling AHornemann GUlrich AHoehl MKruskopf KPierz MRaschke GWübbeler CElster article KhaninARE2018 IEEE Transactions on Medical Imaging 2018 6 19 37 12 2687--2694 8.4, 8.42 10.1109/TMI.2018.2848104 AKhanin MAnton MReginatto CElster article PossoloBBMW2018 Metrologia 2018 5 9 55 3 404 8.4, 8.42 10.1088/1681-7575/aabd57 APossolo OBodnar T AButler J LMolloy M RWinchester article BeckerFNRMB2018 Chaos: An Interdisciplinary Journal of Nonlinear Science 2018 4 30 28 4 043121 8.4, 8.41, 8.43 10.1063/1.5018139 MBecker TFrenzel TNiedermayer SReichelt AMielke MBär article SchachtschneiderFSABBBBKKLLMPRSSWWSE2018 Measurement Science and Technology 2018 4 9 29 5 055010 8.4, 8.42, KC, Form 10.1088/1361-6501/aaae96 RSchachtschneider IFortmeier MStavridis JAsfour GBerger R BBergmann ABeutler TBlümel HKlawitter KKubo JLiebl FLöffler RMeeß CPruss DRamm MSandner GSchneider MWendel IWiddershoven MSchulz CElster article AntonKKRE2018 Physics in Medicine & Biology 2018 3 27 63 7 5011 8.4,8.42 10.1088/1361-6560/aab24a MAnton AKhanin TKretz MReginatto CElster article KlauenbergKKRE2018 Quality and Reliability Engineering International 2018 2 26 8.4, 8.42, Stichprobenverf 10.1002/qre.2256 KKlauenberg RKramer CKroner JRose CElster article ReinkenKBH2018 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 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 Metrologia 2018 2 2 55 2 147 8.4, 8.42 10.1088/1681-7575/aaa5be APossolo OBodnar article BodnarE2016 AStA Advances in Statistical Analysis 2018 1 31 102 1 1--20 8.42,KC,Unsicherheit 10.1007/s10182-016-0279-7 OBodnar CElster article WubbelerBE2018 Metrologia 2018 1 2 55 1 20 8.4,8.42,Unsicherheit,Regression 10.1088/1681-7575/aa98aa GWübbeler OBodnar CElster article DierlEFKEE2018 Journal of the European Optical Society-Rapid Publications 2018 1 2 14 1 1 8.4,8.42 10.1186/s41476-017-0069-1 MDierl TEckhard BFrei MKlammer SEichstädt CElster article GiengerBN2018 Applied Optics 2018 1 1 57 2 344 -- 355 8.4,8.41,Cyto 10.1364/AO.57.000344 JGienger MBär JNeukammer article BuranBN2017 Chaos 2017 11 19 27 11 113110 8.4,8.43,8.41 10.1063/1.5010787 PBuran MBär SAlonso TNiedermayer article AlonsoREB2017 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 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 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 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 LWerner GWuebbeler MWhite article WubbelerE2017 SIAM J. Imaging Sci. 2017 8 21 10 3 979--1004 8.4,8.42,Fingerprinting,LargeScaleDataAna 10.1137/16M1095032 GWübbeler CElster article WeissenbrunnerFJT2017 Eccomas Proceedia UNCECOMP 2017 6 17 5393 576--587 8.4,8.41,Flow,UQ 10.7712/120217.5393.16913 AWeissenbrunner AFiebach MJuling P UThamsen article ReginattoAE2017 Metrologia 2017 6 14 54 4 S74--S82 8.4,8.42,Unsicherheit 10.1088/1681-7575/aa735b MReginatto MAnton CElster article EichstadtW2017 J. Acoust. Soc. Am. 2017 6 6 141 6 4155--4167 8.4,8.42,Unsicherheit,Dynamik 10.1121/1.4983827 SEichstädt VWilkens article BodnarBE2017 Metrologia 2017 5 11 54 3 S29--S33 8.4,8.42,Unsicherheit 10.1088/1681-7575/aa69ad OBodnar RBehrens CElster article KobuschE2017 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 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 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 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 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 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 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 Color Research & Application 2016 12 31 8.4,8.42,Unsicherheit 10.1002/col.22109 GWübbeler JCampos Acosta CElster article BodnarS2016 Statistics 2016 12 27 51 4 722--744 8.4,8.42 10.1080/02331888.2016.1268616 OBodnar WSchmid article GiengerGNB2016 Applied Optics 2016 11 25 55 31 8951--8961 8.4,8.41,Cyto 10.1364/AO.55.008951 JGienger HGroß JNeukammer MBär article AlonsoWB2016 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 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 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 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 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 Proceedings of the 17th International Flow Measurement Conference FLOMEKO 2016 2016 9 29 8.4,8.41,Flow AFiebach ESchmeyer SKnotek SSchmelter article KnotekFS2016 Proceedings of the 17th International Flow Measurement Conference FLOMEKO 2016 2016 9 29 8.4,8.41,Flow SKnotek AFiebach SSchmelter article HeidenreichDKB2016 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 Phys. Rev. E 2016 93 4 043306 8.4,8.41 10.1103/PhysRevE.93.043306 JGienger NSeverin JRabe I MSokolov article SH 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 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 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 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 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 Phys. Rev. E 2015 1 7 91 022703 8.41, Herz 10.1103/PhysRevE.91.022703 MRadszuweit EAlvarez-Lacalle MBär BEchebarria article Klauenberg2015_3 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 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 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 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 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 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 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 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 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 Phys. Rev. E 2015 1 1 92 5 8.43 8.43 10.1103/PhysRevE.92.052137 TNiedermayer RLipowsky article Klauenberg2015 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 Phys. Rev. E 2014 89 052909 8.41, RD 10.1103/PhysRevE.89.052909 JSiebert SAlonso MBär ESchöll article Meyer2014 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 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 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 Technische Sicherheit 2014 11 13--17 8.41 8.41, Flow GWendt RJost SSchmelter DWerner article Eichstaedt2014 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 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>&amp;</prt>seq=0<prt>&amp;</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 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>&amp;</prt>seq=0<prt>&amp;</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 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 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 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 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 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 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 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 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>&amp;</prt> Francis Group en 10.1080/03610926.2013.841925 10.1080/03610926.2013.841925 BArendacká article Arendacka2014b 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 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 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 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 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 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 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 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 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, ’non-rough’ 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 &sigma;<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 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 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>&amp;</prt>seq=0<prt>&amp;</prt>html=true Optical Society of America EN 1094-4087 10.1364/OE.22.021313 IFortmeier MStavridis AWiegmann MSchulz WOsten CElster article Fiebach2014 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 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 Proceedings of Flomeko 2013 16th International Flow Measurement Conference 2013 12 31 8.41, Flow SSchmelter RModel GWendt MBär article JegouNLCR2013 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 Phys. Rev. Lett. 2013 110 228102 8.43, ActFluid 10.1103/PhysRevLett.110.228102 JDunkel SHeidenreich KDrescher H. HWensink MBär R. EGoldstein article Radszuweit2013 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 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 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 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 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 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 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 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 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 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 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 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 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 Physics 2013 6 8.41, ActMatter http://physics.aps.org/articles/v6/61 American Physical Society en IAranson article Elster2013 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 2013 8.41, ActMatter TU Berlin MRadszuweit phdthesis Kohl2013 2013 8.42,Gehirn,SingleTrial TU Berlin PhD Thesis FKohl phdthesis Henn_Thesis 2013 8.41,8.42,Scatter-Inv,Scatterometrie 8.41,Scatter-Inv TU Berlin M-AHenn phdthesis Fiebach2013 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 (&lt; 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 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 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 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 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>&amp;</prt>seq=0<prt>&amp;</prt>html=true Optical Society of America EN 1094-4087 10.1364/OE.20.012771 M-AHenn HGross FScholze MWurm CElster MBär article Elster2012c 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 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>&amp;</prt>seq=0<prt>&amp;</prt>html=true Optical Society of America EN 1539-4522 10.1364/AO.51.007384 HGroß M-AHenn SHeidenreich ARathsfeld MBär article Fuser2012 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 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 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 2012 Advanced Mathematical & Computational Tools in Metrology and Testing IX&nbsp; 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 2012 Advanced Mathematical & Computational Tools in Metrology and Testing IX &nbsp; 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 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 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 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 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 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&amp;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&amp;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 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 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 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 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 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 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 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 44mm−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 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 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 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 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.Bär, 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 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 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 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 Technische Sicherheit 2011 1 18--27 8.41, Flow HFörster WGünther GLindner RModel article Fruhner_CC2010 Comp. Cardiology 2010 37 867 8.41, Herz SFruhner HEngel MBär article Peruani2011a 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 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 NeuroReport 2010 21 3 196--200 8.42, Gehirn SLeistner TSander GWübbeler ALink CElster GCurio LTrahms B MMackert article Wiegmann2010 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>&amp;</prt>seq=0<prt>&amp;</prt>html=true Optical Society of America EN 1094-4087 10.1364/OE.18.015807 AWiegmann MSchulz CElster article Schulz2010 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 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 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 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 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 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 accelerometer’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 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 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 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 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 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 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 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 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 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 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 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 &mu;m-1) on a specifically designed chirp specimen with sinusoidal waves of amplitude 100 nm and wavelengths from 2.5 mm down to 19 &mu;m. 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>&amp;</prt>seq=0<prt>&amp;</prt>html=true Optical Society of America EN 1094-4087 10.1364/OE.17.011098 AWiegmann MSchulz CElster article Wubbeler2009 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 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 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 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 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 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 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 2009 8.42,Form, SimOpt http://dx.doi.org/10.14279/depositonce-2278 TU Berlin PhD Thesis AWiegmann article NiedermayerEL2013 Chaos 2008 1 1 18 8.43 8.43 10.1063/1.2956984 TNiedermayer BEckhardt PLenz article Model2008 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 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 ∕ 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 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>&amp;</prt>seq=0<prt>&amp;</prt>html=true Optical Society of America EN 1094-4087 10.1364/OE.16.011975 AWiegmann MSchulz CElster article Schulz2008 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 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 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 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 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>&amp;</prt> Francis Group en 1745-5030 10.1080/17455030701481823 HGroß ARathsfeld article Elster2008c 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 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 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>&amp;</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 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 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 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 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 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 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 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 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 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 THERMAL CONDUCTIVITY 2006 28 298--308 8.41 8.41 RModel RStosch UHammerschmidt article Nicola2006 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 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 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 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 tm - Technisches Messen 2006 73 12 675-683 8.42,Dynamik 10.1524/teme.2006.73.12.675 ALink MKobusch TBruns CElster article Leistner2006 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 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 Optical Engineering 2006 45 6 8.42,Form,SimOpt 10.1117/1.2208568 MSchulz CElster article Borner2006 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>&amp;</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 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 THERMAL CONDUCTIVITY 2006 28 288--297 8.41 8.41 UHammerschmidt VMeier RModel article Gross2006 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 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 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 Thermal Conductivity 26/Thermal Expansion 14 2005 346--357 8.41, Flow RModel UHammerschmidt article Model2005 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 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 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 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 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 Circulation 2005 112 e68--e69 8.42 10.1161/CIRCULATIONAHA.104.494104 LSchmitz MBurghoff article Bousseljot2005 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 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 Biomed. Tech. 2005 50 1 179--180 8.41 8.41, BioMed MBurghoff B MMackert WHaberkorn article John2005b 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 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 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 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 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