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arXiv 2020年

作者： Fox, Colin Cui, Tiangang Neumayer, Markus Department of Physics University of Otago Dunedin New Zealand School of Mathematics Monash University Melbourne Australia Institute of Electrical Measurement and Sensor Systems Graz University of Technology Graz Austria

Bayesian modelling and computational inference by Markov chain Monte Carlo (MCMC) is a principled framework for large-scale uncertainty quantification, though is limited in practice by computational cost when implemented in the simplest form that requires simulating an accurate computer model at each iteration of the MCMC. The delayed acceptance Metropolis–Hastings MCMC leverages a reduced model for the forward map to lower the compute cost per iteration, though necessarily reduces statistical efficiency that can, without care, lead to no reduction in the computational cost of computing estimates to a desired accuracy. Randomizing the reduced model for the forward map can dramatically improve computational efficiency, by maintaining the low cost per iteration but also avoiding appreciable loss of statistical efficiency. Randomized maps are constructed by a posteriori adaptive tuning of a randomized and locally-corrected deterministic reduced model. Equivalently, the approximated posterior distribution may be viewed as induced by a modified likelihood function for use with the reduced map, with parameters tuned to optimize the quality of the approximation to the correct posterior distribution. Conditions for adaptive MCMC algorithms allow practical approximations and algorithms that have guaranteed ergodicity for the target distribution. Good statistical and computational efficiencies are demonstrated in examples of calibration of large-scale numerical models of geothermal reservoirs and electrical capacitance tomography. Copyright © 2020, The Authors. All rights reserved.

关键词： Computational efficiency

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Recapitulation and comparative study for Photovoltaic Maximum Power Point Tracking techniques in particular sensor quality

Recapitulation and comparative study for Photovoltaic Maximu...

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IEEE Palestinian International Conference on Electrical and Computer Engineering (PICECE)

作者： Hala Jarallah El Khozondar Lee Jun yong Alexander W. Koch Islamic University of Gaza Gaza Plestine Institute for Measurement Systems and Sensor Technology German Institute for Science and Technology Singapore Institute for Measurement Systems and Sensor Technology Technische Universitaet Muenchen TUM Muenchen Germany

In this study, a review on several maximum power point tracking (MPPT) algorithms is given. MPPT algorithms have three major categories: Conventional methods, Advanced Soft Computing methods and Hybrid algorithms. MPPT algorithms are significant to operate the photovoltaic energy conversion systems as close as possible to the MPP resulting in photovoltaic (PV) arrays with high efficiency. In this review, the MPPT algorithms implementation complexity, the complete procedure and its effects in the PV output were given with special attention to the sensors used in the system in the first portion. Further, different MPPT algorithms for PV systems are highlighted with examples, it's parameters like complexity, and sensors used are described. In the end, the MPPT algorithms for PV systems were compared, reviewed and reported. The ultimatum of this work is to provide a survey reference for users of PV based power generation and valued information for researchers of this particular field.

关键词： Maximum power point trackers Complexity theory Photovoltaic systems Artificial neural networks Fuzzy logic Solar energy

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On the development and qualification of multiaxial designs of nanofabrication machines with ultra precision tool rotations 19

On the development and qualification of multiaxial designs o...

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

作者： Schienbein, Ralf Fern, Florian Theska, René Füßl, Roland Institute of Design and Precision Engineering Precision Engineering Group Department of Mechanical Engineering Technische Universität Ilmenau Germany Institute of Process Measurement and Sensor Technology Department of Mechanical Engineering Technische Universität Ilmenau Germany

ISBN: (纸本)9780995775145

The majority of nanopositioning and nanomeasuring machines (NPMMs) are based on three independent linear movements in a Cartesian coordinate system with a repeatability in the nanometer range. This in combination with the specific nature of sensors and tools limits the addressable part geometries. This article contributes to the enhancement of multiaxial machine structures by the implementation of rotational movements while keeping the precision untouched. A parameter based dynamic evaluation system with quantifiable technological parameters has been set up and employed to identify general solution concepts and adequate substructures. It further on contains data based on comprehensive design catalogues, uncertainty calculations and CAD-model based footprint analysis for specific setups. First evaluations show high potential for sample scanning mode variants considering linear movements of the object in combination with angular movements of the tool, considering a goniometer setup in specific. Based on this, positioning systems for the tool rotation of a NPMM were selected and the positioning properties of different arrangements were determined in test series using autocollimators. General properties of the influence of the arrangement were derived. The arrangement of the substructures which fulfils the previous given requirements is integrated into the NPMM and investigated for long-term stability using a retroreflector as a tool and various laser interferometers. The influence of the additional positioning systems on the existing structure of NPMMs are investigated and solutions for the optimization of the overall system with regard to reproducibility and long-term stability are developed. For this purpose, comprehensive FEA simulations are carried out and structural adjustments are derived via topology optimizations. After all, the knowledge gained is formed into general rules for the verification and optimization of design solutions for multiaxial nanopositioning

关键词： Nanotechnology

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Tracking of Magnetic Micromotors in Confined Channels Through Scattering Tissue

Tracking of Magnetic Micromotors in Confined Channels Throug...

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IEEE International Conference on Nano/Molecular Medicine and Engineering (NANOMED)

作者： Azaam Aziz Dmitriy Karnaushenko Nektarios Koukourakis Jürgen W. Czarske Oliver G. Schmidt Mariana Medina-Sánchez Institute for Integrative Nanosciences Leibniz Institute for Solid State and Materials Research Dresden Germany Chair of Measurement and Sensor System Technique and Competence Center BIOLAS TU Dresden School of Engineering Dresden Germany Cluster of Excellence Physics of Life TU Dresden Germany and Faculty of Physics School of Science Dresden TU Germany Professorship of Material Systems for Nanoelectronics Chemnitz University of Technology Chemnitz Germany

ISBN: (纸本)9781665458573

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.

关键词： Stimulated emission Fluid dynamics Scattering Optical imaging Spatiotemporal phenomena Optical scattering Optical reflection

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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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Mechanical properties of an adjustable weighing cell prototype 19

Mechanical properties of an adjustable weighing cell prototy...

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

作者： Darnieder, Maximilian Pabst, Markus Fröhlich, Thomas Zentner, Lena Theska, René Department of Mechanical Engineering Technische Universität Ilmenau Institute for Design and Precision Engineering Precision Engineering Group Department of Mechanical Engineering Technische Universität Ilmenau Institute for Process Measurement and Sensor Technology Process Measurement Technology Group Germany Department of Mechanical Engineering Technische Universität Ilmenau Compliant Systems Group Germany

ISBN: (纸本)9780995775145

Weighing cells based on the principle of electromagnetic force compensation are highly sensitive force measuring devices. A compliant mechanism with thin flexure hinges constitutes the mechanical basis of the balance. The weighing cells are the core components of high-performance vacuum mass comparators, e.g. for the comparison of one kilogram mass standards. According to the mechanical models, the achievable sensitivity of the measurement device is only limited by the adjustment resolution. Without further measures, the vertical adjustment of small trim masses represents a trade-off between resolution and tilt sensitivity. The numerical test of the underlying adjustment concept by finite element models reveals that the objectives of a high sensitivity and a low tilt sensitivity can be achieved simultaneously by a meaningful combination of adjustment measures. This represents a promising concept for the further enhancement of vacuum mass comparators. The prototypes are planar weighing cell structures for a flexible choice of the manufacturing process. The planar mechanism facilitates the comparison between models and measurements. The weighing cells for a nominal mass of 300g are experimentally investigated. The measurement of tilt reactions is enabled by the use of a precision tilt table as base for the weighing cell. Properties like stiffness and tilt sensitivity are determined as a function of the adjustment parameters. This way the mechanical models are verified, and the property enhancement of the weighing cell is evaluated. © 2019 European Society for Precision Engineering and Nanotechnology, Conference Proceedings - 19th International Conference and Exhibition, EUSPEN 2019. All rights reserved.

关键词： Cells

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Progress towards comparison of quantum and classical vacuum standards

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measurement: sensors 2021年 18卷

作者： D.S. Barker N.N. Klimov E. Tiesinga J.A. Fedchak J. Scherschligt S. Eckel Sensor Science Division National Institute of Standards and Technology Gaithersburg MD USA Quantum Measurement Division National Institute of Standards and Technology Gaithersburg MD USA

We present our progress towards a comparison of NIST's cold atom primary vacuum standard and a dynamic expansion vacuum standard. The cold atom vacuum standard (CAVS) converts the loss rate of atoms from a magnetic trap to a vacuum pressure using ab initio calculations of the quantum atom-molecule collision cross-section. To validate the CAVS, we have constructed a new flowmeter and dynamic expansion system that can produce low-uncertainty pressures in the ultra-high-vacuum range that is required for atom trapping. We discuss the operation and systematics of both the CAVS and flowmeter.

关键词： Vacuum metrology Laser cooling Atom-molecule scattering

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Energy-efficient Routing of Electric Vehicles with Integrated Photovoltaic Installations

Energy-efficient Routing of Electric Vehicles with Integrate...

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IEEE Instrumentation and measurement technology Conference

作者： Christian Schuss Tapio Fabritius Bernd Eichberger Timo Rahkonen Optoelectronics and Measurement Techniques (OPEM) Research Unit University of Oulu Finland Institute of Electronic Sensor Systems Graz University of Technology Austria Circuits and Systems (CAS) Research Unit University of Oulu Finland

ISBN: (数字)9781728144603

ISBN: (纸本)9781728144610

This paper investigates the potential output power of photovoltaic (PV) installations on top of battery-powered electric vehicles (BEVs) and hybrid electric vehicles (HEVs). By choosing different routes within urban areas, we expect different output power levels from the vehicle's PV installation. Hence, we calculate energy profiles to estimate the PV energy which can be gained during driving conditions to choose the most energy-efficient route for BEVs and HEVs. While driving duration, driving distance and traffic conditions are some of the criteria within the decision-making process of routing algorithms, in this paper, we focus on energy-efficiency of routing algorithms. We present experimental data to highlight the importance of energy profiles for improving and maximising of the electrical driving distance of BEVs and HEVs.

关键词： algorithm battery-powered electric vehicle data acquisition energy profile environmental data hybrid electric vehicle measurement photovoltaic energy solar energy Hybrid electric vehicles Photovoltaic energy Energy efficiency Environmental data Electric vehicles Data Collection Methods Solar Energy Routing algorithms Installations ROADWAY-POWERED ELECTRIC VEHICLES algorithms Automobile driving Output power

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Erratum to “Static and Dynamic Pressure measurement in Flight Test Application With Optical Fabry–Pérot sensors”

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IEEE Transactions on Instrumentation and measurement 2021年 70卷

作者： Sascha U. Kienitz Laura Lohr Markus J. Schmid Alexander W. Koch PolyTech Wind Power Technology Germany GmbH Munich Germany Institute for Measurement Systems and Sensor Technology Technical University Munich Munich Germany

In the above article [1] , (5) on page 3, a typo was observed when preparing a new manuscript. This equation was added with respect to the decision of major revision. The initial template for the revision contained the correct formulae, but based on most likely a formatting issue on the main author’s side from with (4), the equation was mixed up with (5). Unfortunately, this mistake was not observed by reviewers or the coauthors.

关键词： Optical variables measurement Adaptive optics Pressure measurement Optical sensors

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Investigating the interlayer electron transport and its in?uence on the whole electric properties of black phosphorus

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Science Bulletin 2019年第4期64卷 254-260页

作者： Bensong Wan Shaoqiang Guo Jiacheng Sun Yufei Zhang Yuyan Wang Caofeng Pan Junying Zhang Key Laboratory of Micro-nano Measurement Manipulation and Physics (Ministry of Education) School of Physics Beihang University CAS Center for Excellence in Nanoscience Beijing Key Laboratory of Micro-nano Energy and Sensor Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of Sciences School of Nanoscience and Technology University of Chinese Academy of Sciences Center on Nanoenergy Research School of Physical Science and Technology Guangxi University College of Optoelectronic Engineering Shenzhen University

Two-dimensional(2D) nanomaterials have attracted great attention in next generation electronic and optoelectronic technologies due to the unique layered structure and excellent physical and chemical properties. However, the mechanism of transmission along the vertical direction of 2D semiconductor materials has not been investigated. Here, we use first-principles calculations to explore the bandgap energies along different directions, and fabricate a vertical, a lateral and a mixture-structured black phosphorus field effect transistor(BPFET) to study the electrical characteristics along different directions under variable temperatures. The variable temperature test indicates that the mixture-structured device performs more like a lateral device, while the conductance along the vertical direction is hard to be tuned by temperature and electrical field. The unchanged conductance under electric field and variable temperatures allows the vertical device to act as a fixed resistor, promising possible application for the prospective electronic and optoelectronic devices.

关键词： Black phosphorus Transistor Transmission Vertical Variable temperature

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