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Impedance Spectroscopy (IWIS), International Workshop on

作者： Oumaima Bader Mariem Hafsa Najoua Essoukri Ben Amara Olfa Kanoun Professorship Measurement and Sensor Technology Technische Universität Chemnitz Chemnitz Germany LATIS- Laboratory of Advanced Technology and Intelligent Systems Université de Sousse Ecole Nationale d'Ingénieurs de Sousse Sousse Tunisie

Electrical impedance tomography (EIT) is a non-invasive imaging technique for investigating the conductivity distribution within biological tissues by applying a low alternating electrical signal to the medium under test (MUT) and measuring the voltage drops resulting in defined positions. These measurements are subjected to image reconstruction algorithms to deliver the conductivity distribution in the specified MUT. As part of the EIT image reconstruction process, the forward problem is crucial, in which the MUT needs to be modeled accurately in its geometry and expected conductivity. In this paper, a 2D numerical model of the human thorax with real electrical characteristics has been elaborated using COMSOL Multiphysics. Besides, the complete electrode model (CEM) detailing the electrode-MUT interface and the effect of the contact impedance on the resulting potential distribution is studied for the two states of breathing, which are the exhale and the inhale. Finally, a generic 2D model of the human thorax is presented.

关键词： Electrodes Electrical impedance tomography Electric potential Voltage measurement Imaging Conductivity Thorax

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3D Image Reconstruction based on Electrical Impedance Tomography measurements using a Gauss-Newton Algorithm

3D Image Reconstruction based on Electrical Impedance Tomogr...

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Impedance Spectroscopy (IWIS), International Workshop on

作者： Mariem Hafsa Oumaima Bader Zheng Hu Najoua Essoukri Ben Amara Olfa Kanoun LATIS- Laboratory of Advanced Technology and Intelligent Systems Université de Sousse Ecole Nationale d'Ingénieurs de Sousse Sousse Tunisie Professorship of Measurement and Sensor Technology Technische Universität Chemnitz Chemnitz Germany

Electrical Impedance Tomography (EIT) is a non-invasive imaging technique in which a current is injected into the measurement medium and based on the attained boundary voltages that appear on its surface, its inner conductivity distribution can be determined. The injected current is not contained to one plane and has a three-dimensional flow, hence it is interesting to investigate 3D measurements and reconstructions based on EIT measurements. In this work, a framework for 3D EIT measurements has been developed using a water tank along with the corresponding forward model and image reconstruction algorithm based on EIDORS. Different measurements have been conducted using a conductive and a non-conductive objects that were placed in the water tank. Tests have shown that the used 2D hardware can also be used for 3D measurements. In addition, in terms of reconstructed conductivity images, the position of the measured objects is clearly visible and a distinction between the conductive and non-conductive has been attained.

关键词： Electrodes Electrical impedance tomography Three-dimensional displays Impedance measurement Voltage measurement Current measurement Conductivity measurement

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Tonic-Myoclonic Epileptic Seizure Classification based on Surface Electromyography

Tonic-Myoclonic Epileptic Seizure Classification based on Su...

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IEEE SSD International Multi-Conference on systems, Signals and Devices

作者： Achraf Djemal Dhouha Bouchaala Ahmed Fakhfakh Olfa Kanoun Chair of Measurement and Sensor Technology Chemnitz University of Technology Chemnitz University Germany National Engineering School of Sfax University of Sfax Tunisia Laboratory of Signals Systems Artificial Intelligence and Networks Digital Research Center of Sfax University of Sfax Tunisia

Epilepsy diagnosis is one of the critical subjects of research in health fields in recent years. The aim of this paper is to detect and classify two types of seizures: Tonic and myoclonic based on surface electromyography signals. Based on data from eight sEMG electrodes on the biceps brachii, flexor carpi ulnaris, gastrocnemius and quadriceps muscle. Several time domain features were investigated, including waveform length, mean absolute value, variance, mobility, complexity, kurtosis, skewness, simple square integral, integrated EMG, root mean square, average amplitude change, standard deviation and entropy. These features are used as inputs to the Artificial Neural Network (ANN) classifier to determine if a data segment corresponds to a seizure or not. Following the development of the ANN model, an evaluation performance in terms of accuracy is presented to validate the results, which reached an accuracy of 93.33%. The overall performance of the presented machine learning algorithm is sufficient for clinical implementation.

关键词： Machine learning algorithms Surface waves Epilepsy Artificial neural networks Muscles Electromyography Classification algorithms

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Kinematic simulation to investigate the influence of the cutting edge topography when ball end micro milling 18

Kinematic simulation to investigate the influence of the cut...

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18th CIRP Conference on Modeling of Machining Operations, CMMO 2021

作者： Klauer, Katja Altherr, Nicolas Eifler, Matthias Kirsch, Benjamin Böß, Volker Seewig, Jörg Aurich, Jan C. Institute for Manufacturing Technology and Production Systems Technische Universität Kaiserslautern Gottlieb-Daimer Str. Kaiserslautern67663 Germany Institute for Measurement and Sensor-Technology Technische Universität Kaiserslautern Gottlieb-Daimer Str. Kaiserslautern67663 Germany IU University of Applied Sciences Juri-Gagrin-Ring 152 Erfurt99084 Germany Institute of Production Engineering and Machine Tools Leibniz Universität Hannover An der Universität 2 Gabsen30823 Germany

During the ball end micro milling of material measures, the cutting edge topography is imaged on the machined workpiece. The influence of the chipping on the resulting surface quality is much more dominant than other kinematic effects. In this simulative study, a model is built that is able to predict the correlation between the cutting edge topography and the resulting workpiece topography. Thus, the mentioned correlation can be investigated without overlaying effects of material separation or measurement uncertainties, which are unavoidable in an experimental study. The model has been validated based on four artificial chippings. © 2021 Elsevier B.V.. All rights reserved.

关键词： Topography

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Multi-frequency photothermal interferometry of single aerosol particles

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Journal of Aerosol Science 2025年 189卷

作者： Felix W. Stollberger Michael J. Gleichweit Ruth Signorell Alexander Bergmann Institute of Electrical Measurement and Sensor Systems Graz University of Technology Inffeldgasse 33 Graz 8010 Austria Department of Chemistry and Applied Biosciences ETH Zurich Vladimir-Prelog-Weg 1-5/10 Zurich 8093 Switzerland

The frequency dependence of photothermal and photoacoustic signals provides information on evaporation, condensation, and heat transfer processes in aerosol particles. Performing such measurements at the single particle level increases accuracy and provides access to various particle properties. Previously, this was not possible due to the resonant acoustic signal amplification required in photoacoustics, which restricted usable modulation frequencies to a single value. In this study, we introduce the use of multi-frequency photothermal interferometry (n ω -PTI) on single, optically trapped particles and experimentally investigate the frequency dependence of the photothermal signal. The observed signal and its dependence on the optical and thermophysical properties of the particle and the interferometer probe beam are analyzed by an accompanying theoretical model. Our measurements prove the applicability of the presented method and indicate a stronger frequency dependence of the photothermal amplitude from single particles than previously observed in bulk measurements. Furthermore, we were able to decouple the contributions from the particle temperature and the thermal wave propagation and examine their frequency dependencies individually. Finally, we analyzed the direct influence of the particle on the measured signal and showed the potential of frequency-resolved photothermal measurements to study thermophysical parameters or optical properties at the single particle level in the Knudsen transition regime.

关键词： Photothermal interferometry Single particle Heat transfer Multi-frequency Fabry–Pérot interferometer Thermal wave

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Tracking of Magnetic Micromotors in Confined Channels Through Scattering Tissue 15

Tracking of Magnetic Micromotors in Confined Channels Throug...

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15th IEEE International Conference on Nano/Molecular Medicine and Engineering, NANOMED 2021

作者： Aziz, Azaam Karnaushenko, Dmitriy Koukourakis, Nektarios Czarske, Jurgen W. Schmidt, Oliver G. Medina-Sanchez, Mariana Institute For Integrative Nanosciences Leibniz Institute For Solid State And Materials Research Dresden01069 Germany Measurement And Sensor System Technique And Competence Center Biolas Tu Dresden School of Engineering Dresden01069 Germany School of Science Cluster of Excellence Physics of Life Tu Dresden Germany Faculty of Physics Dresden TU Germany Professorship of Material Systems For Nanoelectronics Chemnitz University of Technology Chemnitz09111 Germany

ISBN: (纸本)9781665458566

The field of small-scale microdevices is growing rapidly towards the development of tethered/untethered microsensors and therapeutic agents that can move through narrow vascular networks in living organisms to diagnose and treat for example vascular diseases. However, imaging and localization of such microdevices are challenging under scattering tissue due to the lack of high spatial and temporal resolution that compromises the penetration depth and therefore the application scenario. Here, we report the tracking of magnetically-driven rolling micromotors (20 μm in diameter) through scattering tissue (1.2 mm thickness) using reflective infrared (IR) imaging. This technique provides high spatiotemporal resolution for the tracking of micro-agents in a narrow vascular network. As a potential application, we suggest the use of such micro-agents as micro-viscosimeters, in which by analyzing their dynamics, one can extract some basic information on the surrounding fluid properties which might be related to certain health status. © 2021 IEEE.

关键词： Micromotors

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Switching mechanism for off-grid hybrid power system (photovoltaic-wind) with storage battery 7

Switching mechanism for off-grid hybrid power system (photov...

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7th IEEE Palestinian International Conference on Electrical and Computer Engineering, PICECE 2019

作者： Khozondar, Hala Jarallah El Zainuddin, Siti Zafarh Bte Koch, Alexander W. Electrical Engineering Department Islamic University of Gaza P.O.Box 108 Gaza Palestine Institute for Measurement Systems and Sensor Technology German Institute for Science and Technology GIST-TUM Asia Singapore Singapore Institute for Measurement Systems and Sensor Technology Technische Universitaet Muenchen TUM MuenchenD-80333 Germany

ISBN: (纸本)9781538662915

This work describes a modelling and simulation of the switching mechanism of an off-grid hybrid power system. An offgrid system means that it is not connected to an electricity grid or network. An off-grid power system is important especially at catastrophe times and war where it is hard to get electricity from a utility grid. In addition to that, owners of residential and small-scale commercial structures which are located in remote areas will be able to have access to the electricity. The switching mechanism depends on the renewable energy amount. An off-grid hybrid power system utilizes an array of deep-cycle batteries to store the power generated by the solar panels and a wind turbine. When the renewable sources have excess energy, it is stored in the battery. However, If the renewable sources do not supply enough energy to the loads, the switching mechanism will let the battery provide the load with the required energy. The simulation results in this work show the advantages of using the off-grid system to produce electricity or power from one or more source of renewable energy. © 2019 IEEE.

关键词： Electric power transmission networks

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Design and machining of a calibration artefact for an angular-resolved scattering light sensor 19

Design and machining of a calibration artefact for an angula...

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19th International Conference of the European Society for Precision Engineering and Nanotechnology, EUSPEN 2019

作者： Klauer, Katja Eifler, Matthias Stelzer, Gerhard Kirsch, Benjamin Seewig, Jörg Aurich, Jan C. Technische Universität Kaiserslautern Institute for Manufacturing Technology and Production Systems Germany Technische Universität Kaiserslautern Institute for Measurement and Sensor-Technology Germany

ISBN: (纸本)9780995775145

Angular-resolved scattering (ARS) light sensors are a state of the art technique for in-process and on-machine measurement applications. They do not measure height values, but angles, which results into a high robustness regarding vibrations. The sensor requires corresponding calibration artefacts which can ensure a defined measurement uncertainty and a traceability of the measurement results. As the height values are not the actual measurand of the sensor, the traceability regarding the unit of length is a challenging task which is not yet standardized. A calibration artefact was designed which images and calibrates multiple properties of the ARS sensor. The M- and Aq-value as defined in the guideline VDA 2009 are imaged with different values. Based on stylus instrument measurements and a subsequent virtual ARS light sensor measurement, the suitability of different types of profiles for the calibration of the Aq-value are examined. It is demonstrated that the manufacturing method of ultra-precision turning provides the opportuinity to manufacture different suitable microstructured surfaces for the calibration of ARS light sensors. © 2019 European Society for Precision Engineering and Nanotechnology, Conference Proceedings - 19th International Conference and Exhibition, EUSPEN 2019. All rights reserved.

关键词： Calibration

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Dictionary-Based Learning for 3D-Imaging with Air-Coupled Ultrasonic Phased Arrays

Dictionary-Based Learning for 3D-Imaging with Air-Coupled Ul...

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IEEE International Ultrasonics Symposium

作者： Raphael Muller David Schenck Gianni Allevato Matthias Rutsch Jan Hinrichs Mario Kupnik Marius Pesavento Communication Systems Group Technische Universität Darmstadt Germany Measurement and Sensor Technology Group Technische Universität Darmstadt Germany

ISBN: (数字)9781728154480

ISBN: (纸本)9781728154497

The Least Absolute Shrinkage and Selection Operator (LASSO) was recently introduced for imaging of sparse scenes in low sample size scenarios. In this paper, we investigate the imaging capabilities of LASSO for ultrasonic phased arrays operating in air. Using sparse regularization and a dictionary of measured array point responses, 3D images can be generated with only a few, single pulse measurements. A priori, the dictionary of point responses is learned by calibrating the array. The underlying low-rank structure can be adequately expressed by fitting rank-one vectors. A proof of concept shows the imaging potential of our proposed scheme with a real ultrasonic phased array.

关键词： Phased arrays Dictionaries Ultrasonic imaging Ultrasonic variables measurement Imaging Acoustics Arrays

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Tip-and Laser-based 3D Nanofabrication in Extended Macroscopic Working Areas

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Nanomanufacturing and Metrology 2021年第3期4卷 132-148页

作者： Ingo Ortlepp Thomas Frohlich Roland FuBl Johann Reger Christoph Schaffel Stefan Sinzinger Steffen Strehle ReneTheska Lena Zentner Jens-Peter Zollner Ivo WRangelow Carsten Reinhardt Tino Hausotte Xinrui Cao Oliver Dannberg Florian Fern David Fischer Stephan Gorges Martin Hofmann Johannes Kirchner Andreas Meister Taras Sasiuk Ralf Schienbein Shraddha Supreeti Laura Mohr-Weidenfeller Christoph Weise Christoph Reuter Jaqueline Stauffenberg Eberhard Manske Institute of Process Measurement and Sensor Technology Technische Universitat IlmenauEhrenbergstrasse 2998693 IlmenauGermany Control Engineering Group Technische Universitat IlmenauIlmenauGermany Optical Engineering Group.Technische Universitat Ilmenau IlmenauGermany Microsystems Technology Group.Technische Universitat Ilmenau IlmenauGermany Precision Engineering Group.Technische Universitat Ilmenau IlmenauGermany Compliant Systems Group Technische Universitat IlmenauIlmenauGermany Micro-and Nanoelectronic Systems Group Technische Universitat IlmenauIlmenauGermany Nanoscale Systems Group.Technische Universitat Ilmenau IlmenauGermany Division for Research Service and Technology Transfer Technische Universitat IlmenauIlmenauGermany Electronics Technology Group.Technische Universitat Ilmenau IlmenauGermany IMMS Institut flir Mikroelektronik-und Mechatronik-Systeme Gemeinniitzige GmbH(IMMS GmbH) IlmenauGermany Fachgebiet Technische Physik City University of Applied SciencesBremenGermany Lehrstuhl fiir Fertigungsmesstechnik Friedrich-Alexander-U niversitat(FAU)Erlangen-NiirnbergGermany JUMO GmbH&Co.KG FuldaGermany Asphericon GmbH JenaGermany

The field of optical lithography is subject to intense research and has gained enormous ***,the effort necessary for creating structures at the size of 20 nm and below is considerable using conventional *** effort and the resulting financial requirements can only be tackled by few global companies and thus a paradigm change for the semiconductor industry is conceivable:custom design and solutions for specific applications will dominate future development(Fritze in:Panning EM,Liddle JA(eds)Novel patterning *** society for optics and ***,Bellingham,***://***/10.1117/12.2593229).For this reason,new aspects arise for future lithography,which is why enormous effort has been directed to the development of alternative fabrication ***,the technologies emerging from this process,which are promising for coping with the current resolution and accuracy challenges,are only demonstrated as a proof-of-concept on a lab scale of several square *** scale is not adequate for the requirements of modern lithography;therefore,there is the need for new and alternative cross-scale solutions to further advance the possibilities of unconventional *** challenges arise because of the technical progress in various other fields,realizing new and unique functionalities based on nanoscale effects,e.g.,in nanophotonics,quantum computing,energy harvesting,and life *** platforms for basic research in the field of scale-spanning nanomeasuring and nanofabrication are necessary for these tasks,which are available at the Technische Universitiit Ilmenau in the form of nanopositioning and nanomeasuring(NPM)*** this equipment,the limits of technical structurability are explored for high-performance tip-based and laser-based processes for enabling real 3D nanofabrication with the highest precision in an adequate working range of several thousand cubic millimete

关键词： Nanomeasuring Nanopositioning Nanomanufacturing Scale-spanning Tip-based Laser-based Nanofabrication

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