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Predictive modelling of cryogenic hard turning of AISI 52100 based on response surface methodology for the use in soft sensors

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Procedia CIRP 2022年 108卷 270-275页

作者： Felix Grossmann Stephan Basten Benjamin Kirsch Werner Ankener Marek Smaga Tilmann Beck Julian Uebel Jörg Seewig Jan C. Aurich Institute for Manufacturing Technology and Production Systems TU Kaiserslautern Gottlieb-Daimler-Str. 67663 Kaiserslautern Germany Institute of Materials Science and Engineering TU Kaiserslautern Gottlieb-Daimler-Str. 67663 Kaiserslautern Germany Institute for Measurement and Sensor Technology TU Kaiserslautern Gottlieb-Daimler-Str. 67663 Kaiserslautern Germany

This paper focuses on the development of an empirical model for the use in soft sensors to predict the surface layer properties of AISI 52100 machined via cryogenic hard turning. By using response surface methodology, a multiple regression is performed to achieve correlations between the process parameters, the process forces and the temperature, as well as the residual stresses and the austenite content. The results show a predictive R 2 of over 0.75 and indicate that the empirical model can be used in soft sensors for a process control of cryogenic hard turning.

关键词： Predictive Model Hard Machining Surface Integrity Process Control Cryogenic cooling

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Gigawatt-Scale Acousto-Optic Modulation in Ambient Air

Gigawatt-Scale Acousto-Optic Modulation in Ambient Air

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2023 Conference on Lasers and Electro-Optics Europe and European Quantum Electronics Conference, CLEO/Europe-EQEC 2023

作者： Schrödel, Yannick Hartmann, Claas Lang, Tino Zheng, Jiaan Steudel, Max Rutsch, Matthias Salman, Sarper H. Kellert, Martin Pergament, Mikhail Hahn-Jose, Thomas Suppelt, Sven Dörsam, Jan Helge Harth, Anne Leemans, Wim P. Kärtner, Franz X. Hartl, Ingmar Kupnik, Mario Heyl, Christoph M. Deutsches Elektronen-Synchrotron DESY Hamburg Germany Technische Universität Darmstadt Measurement and Sensor Technology Darmstadt Germany Hochschule Aalen Department of Optics and Mechatronics Aalen Germany Helmholtz-Institute Jena Jena Germany GSI Helmholtzzentrum für Schwerionenforschung GmbH Darmstadt Germany Center for Free-Electron Laser Science CFEL Deutsches Elektronen-Synchrotron DESY Hamburg Germany INOSON GmbH St. Ingbert Germany University of Hamburg Department of Physics Hamburg Germany The Hamburg Centre for Ultrafast Imaging Hamburg Germany

ISBN: (纸本)9798350345995

Control over the parameters of a laser beam such as intensity and phase is vital in modern photonics. The established schemes, however, limit the parameter range in which common methods can be applied. The limitations are most prominent in terms of peak-power and wavelength λ, as current methods rely to a large extend on the interaction of light with solid media (e.g. glasses, crystals). We here propose a simple but effective alternative to solid media: gases tailored by intense ultrasound waves via refractive index change induced by density modulations. Earlier works report gas-based refractive optics [1]. However, to the best of our knowledge, more advanced gas-based control schemes such as modulators, deflectors or phase shapers have not entered the photonics field until today. © 2023 IEEE.

关键词： Laser beams

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Accurate high-temperature profile sensing with dense multipoint arrays of regenerated fiber Bragg gratings

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Results in Physics 2024年 65卷

作者： Stadler, Andrea Zeisberger, Andreas Buchfellner, Fabian Roehrl, Alexander Koch, Alexander W. Roths, Johannes Munich University of Applied Sciences Photonics Laboratory Lothstr. 34 Munich 80335 Germany MTU Aero Engines AG Dachauer Str. 665 Munich 80995 Germany Technical University of Munich Institute for Measurement Systems and Sensor Technology Theresienstr. 90 Munich 80333 Germany

A spectrally and spatially dense sensor array consisting of 15 regenerated fiber Bragg gratings (RFBGs) over a length of 30 mm is presented for precise and fast multipoint temperature sensing up to 700°C. For the first time, it could be shown that with a dense fiber Bragg grating (FBG)-based sensor array the accuracy requirements of Class 1 thermocouples could be achieved and even exceeded. This also represents the highest spatial density of FBG-based high-temperature multipoint sensing reported so far. The mitigation of broadband losses during the regeneration process was studied, revealing the advantages of the low broadband loss characteristics of the RFBGs, especially when larger numbers of measuring points are required. Low measurement uncertainties were achieved by a new, improved calibration methodology and by an analysis of interferences of an FBG with the side lobes of spectrally neighboring FBGs as well as their suppression by a suitable arrangement of the Bragg wavelengths within the array and corresponding data processing. The capabilities of this multipoint sensor technique were demonstrated by resolving the temperature profile within the calibration volume of a calibration furnace and by resolving the temporal and spatial temperature gradients within the flame of a Bunsen burner. The results are of great importance for fiber-optic sensing of high-temperature profiles in real-world applications. © 2024 The Authors

关键词： High spatial resolution High-temperature sensing Multipoint Regenerated fiber Bragg gratings

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Research on Laser Spectrum of Large-aperture Antenna Subreflector Pose measurement 6

Research on Laser Spectrum of Large-aperture Antenna Subrefl...

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6th Conference on Frontiers in Optical Imaging and technology: Imaging Detection and Target Recognition

作者： Xuan, Zhang Shangmin, Lin Hu, Wang Ming, Gao Zhen, Wang Yu, Jin Jiang, Qiao Yunqiang, Lai Wenlong, He Yaoke, Xue Xi'an Technological University No.2 Xuefuzhonglu Road Shaanxi Xi'an710021 China Xi’an Institute of Optics and Precision Mechanics Chinese Academy of Science No.17 Xinxi Road Shaanxi Xi'an710119 China University of Chinese Academy of Sciences No.1 Yanqihu East Rd Huairou District Beijing101408 China Xi’an Space Sensor Optical Technology Engineering Research Center No.17 Xinxi Road Shaanxi Xi'an710119 China Key Laboratory of Space Precision Measurement Technology Chinese Academy of Sciences No.17 Xinxi Road Shaanxi Xi'an710119 China Beijing University of Aeronautics and Astronautics Beijing100191 China Youth Innovation Promotion Association Beijing10029 China

ISBN: (数字)9781510679733

ISBN: (纸本)9781510679726

When the large-aperture antenna pose is measured by the laser method, the subreflector has a strong energy due to the convergence of the antenna itself and the instability of the near-ground atmosphere, and then the laser signal is easily drowned out. Atmospheric attenuation and other factors will weaken the laser transmission in different spectral bands, which reduces the recognition accuracy of laser spots. Aiming at the research of measuring the laser spectrum of large-aperture antenna, this paper analyzes the influence of atmospheric attenuation on the signals of different laser spectrum bands under the fixed distance of subreflector measurement, and compares the solar radiation energy of different wavelengths in laser. Finally, the stray light simulation analysis and experiments are carried out on different laser working spectrum bands to verify the accuracy of the spectrum research used in antenna measurement. Experiments show that the 1064 nm wavelength spectrum, as the working spectral band of the antenna measurement, the spot information is more obvious, which can effectively realize the extraction and identification of the spot center and provide a strong guarantee for the antenna pose measurement. © 2024 SPIE. All rights reserved.

关键词： Stray light

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Highly Disaggregated Particulate and Gaseous Vehicle Emission Factors and Ambient Concentration Apportionment Using a Plume Regression Technique

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Environmental Science and technology 2025年第23期59卷 11698-11707页

作者： Farren, Naomi J. Knoll, Markus Bergmann, Alexander Wagner, Rebecca L. Shaw, Marvin D. Wilson, Samuel Bernard, Yoann Carslaw, David C. Wolfson Atmospheric Chemistry Laboratories University of York York YO10 5DD United Kingdom Institute of Electrical Measurement and Sensor Systems Graz University of Technology Inffeldgasse 33/I Graz 8010 Austria Leverhulme Centre for Climate Change Mitigation School of Biosciences University of Sheffield Sheffield S10 2TN United Kingdom The International Council on Clean Transportation Fasanenstr. 85 Berlin 10623 Germany

In this study, vehicle plume measurements from over 27,500 vehicles were made using continuous fast-response instruments located at the curbside for nitrogen oxides (NOx), particle number (PN), and black carbon (BC) in the city of Milan, Italy. A recently developed plume regression technique is further enhanced to calculate highly disaggregated emission factors for a wide range of vehicle classes. The data reveal a strong improvement in the emissions performance for NOx from passenger cars on going from laboratory to on-road testing. However, for emissions of PN and BC, disaggregation by vehicle manufacturers for diesel passenger cars highlights anomalously high emissions from some manufacturers. Emissions from one manufacturer, which predate on-road testing, are up to a factor of 4 higher than the average of other manufacturers and are among those being scrutinized in several European countries through enhanced periodic technical inspections (PTI) that for the first time considered PN. Near-road concentration source apportionment reveals a broader range of vehicle types contributing to PN and BC compared to NOx. The top three contributors to NOx concentrations account for 57% of total NOx but only 28-29% of total PN and BC. These findings have implications for policies such as low-emission zones of the type adopted in Milan and elsewhere in the world. The combination of curbside measurements and plume regression allows for both high-resolution emission measurements and ambient concentration source apportionment. © 2025 The Authors. Published by American Chemical Society.

关键词： particulates plume sampling source apportionment vehicle emissions

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Comparative Study of Optimization Methods Proposed for the Extreme Learning Machine (ELM)

Comparative Study of Optimization Methods Proposed for the E...

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Impedance Spectroscopy (IWIS), International Workshop on

作者： Tayssir Chouikh Hiba Hellara Rim Barioul Faten Sandid Olfa Kanoun University of Sousse National Engineering School of Sousse Sousse Tunisia Measurement and Sensor Technology Technische Universität Chemnitz Chemnitz Germany

The Extreme Learning Machine (ELM) is a learning algorithm used for training a single hidden layer feed-forward neural network (SLFN). It leads to a better generalization performance and fast learning speed and many more advantageous properties. The first step of an ELM is to assign random values to the input weights and biases. Then it will determine the output weights in a single step using the generalized Moore-Penrose method. The random initialization of weights and biases and a large number of hidden nodes can affect the performance of the ELM. Several optimizers were proposed aiming to increase generalization performance and produce more compact networks. This paper presents a comparative study of ELM optimization in the state of the art using existing algorithms namely Optimally Pruned ELM (OP-ELM), Grey Wolf Optimizer (GWO), Salp Swarm Algorithm (SSA), Bat Algorithm (BA), and Particle Swarm Optimization (PSO) which are swarm intelligence-based ELMs. Also Genetic Pruning Algorithm (GPA) and Enhanced Genetic Algorithm (EGA) which are pruning methods using evolutionary algorithms. Results prove that SSA-ELM improves the accuracy in most benchmark datasets and shows better results than the other comparing methods while OP-ELM gives the most compact model with a high level of accuracy.

关键词： Training Spectroscopy Extreme learning machines Neurons Metaheuristics Optimization methods Genetics

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Portable Electronic Devices in Cabin and Cockpit – Analysis of Hazards

Portable Electronic Devices in Cabin and Cockpit – Analysis...

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AIAA Science and technology Forum and Exposition, AIAA SciTech Forum 2025

作者： Holz, Simon Pfaff, Jonas Kuder, Jürgen Schopferer, Sebastian May, Michael Norrefeldt, Victor Pathak, Arnav Pschirer, Marie Kienberger, Maximilian Fraunhofer Institute for High-Speed Dynamics Ernst-Mach-Institut Research Group Computational Physics EMI Dpt. Materials and Simulation Methods Freiburg79104 Germany Fraunhofer Institute for High-Speed Dynamics Dpt. Measurement and Sensor Technology Ernst-Mach-Institut EMI Freiburg79104 Germany Fraunhofer Institute for High-Speed Dynamics Department Resilience Safety and Security Ernst-Mach-Institut EMI Freiburg79104 Germany Fraunhofer Institute for Building Physics IBP Research Group Vehicle Climate Control Systems Dpt. Indoor Climate Valley83626 Germany Fraunhofer Institute for Building Physics IBP Valley83626 Germany

ISBN: (数字)9781624107238

ISBN: (纸本)9781624107238

Multiple portable electronic devices (PED) such as smartphones and laptops are carried during flight in cabin and cockpit by passenger and crew. When the Lithium-Ion batteries of PEDs go into thermal runaway flammable and toxic gases are released. In the first part of this study a total of 26 laptops, tablets, smartphones, and power tool batteries have been forced into thermal runaway in a ventilated test box (V=350 l, V=13 l/s) observing smoke and fire as the main hazards. Correlations of the venting volume depending on the energy content of the PED are presented. The volume released during fire hazard is seven times the volume released during smoke hazard. Up to 3 l of electrolyte and up to 0.4 l hydrogen fluoride, hydrogen chloride and formaldehyde as well as up 20 l of combustion products of plastics are released during the full test time. For tablets and smartphones, the smoldering of plastics prior to the thermal runaway could be noted visually and due to a rise in propane emissions. In the second part of this study thermal runaway tests with laptops in a A320 mockup (V=13 m³) under realistic ventilation (V=60 l/s) are presented. The nine tested laptops were used to generate thermal runaway events on the floor, on seats and in the overhead bin. The increase of air temperature in the cabin depends on the distance from the floor, and may be as high as 60 K. The CO2 concentration level in the cabin increases and it takes 16 to 26 min to restore 105 % of the level measured prior to thermal runaway. Finally, the absolute amounts of vent gases are presented and clustered for e.g. toxic and flammable gases or evaporated electrolyte. The presented data will enable the prediction of local concentrations inside occupied areas of the cabin during thermal runaway by CFD simulations. © 2025, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.

关键词： Fire hazards

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Planar mapping of the liquid fraction of froth using ultrasound Flächige Darstellung des Wassergehaltes von Schaum mittels Ultraschall 21

Planar mapping of the liquid fraction of froth using ultraso...

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21. ITG/GMA-Fachtagung sensoren und Messsysteme - 21st ITG/GMA Conference on sensors and Measuring Systems

作者： Emmerich, Hannes Knüpfer, Leon Trtik, Pavel Eckert, Kerstin Heitkam, Sascha Starke, Eric Weik, David Büttner, Lars Czarske, Jürgen Technical University Dresden Laboratory of Measurement and Sensor System Techniques Dresden01069 Germany Helmholtz-Zentrum Dresden-Rossendorf Institute of Fluid Dynamics Dresden01328 Germany Paul Scherrer Institut Laboratory for Neutron Scattering and Imaging Villigen5232 Switzerland Technical University Dresden Institute of Process Engineering and Environmental Technology Dresden01069 Germany SICK Engineering GmbH Bergener Ring 27 Ottendorf-Okrilla01458 Germany

ISBN: (纸本)9783800758364

Flotation processes are essential processes for resource separation, the monitoring of which can save vast amounts of water and energy. To control them, it is necessary to measure the phase fractions present in the froth. Currently, no suitable measurement method exists that can be easily integrated into the existing process and has a penetration depth of more than 5 cm. Therefore, in this paper we present a measurement system for determining the liquid distribution in foam using ultrasound. To counteract the strong attenuating effect of the foam on the ultrasound, we use low-frequency probes with a center frequency of 135 kHz. Electrodes determine an integral liquid fraction by conductivity measurement. Within a liquid range of 0.17 ·10−2 to 0.82 ·10−2, the measurement system was first calibrated for a penetration depth of 9.2 cm and validated by simultaneous neutron imaging. An absolute and relative measurement uncertainty of 0.23 ·10−2 and 42.5 % was the respective result. A resolution of 7.5 mm in the axial, 13 mm in lateral direction and 1 Hz in time were obtained. In a dynamic inhomogeneous case, the measurement system was additionally validated for a use case. This investigation represents a first step towards process optimization in flotation processes. © VDE VERLAG GMBH ∙ Berlin ∙ Offenbach.

关键词： Ultrasonics

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Noble-metal dark-edge fermiology: Centrifugal barriers, core-hole memory, and the Zeeman Auger effect

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Physical Review B 2021年第24期104卷 245131-245131页

作者： J. C. Woicik E. L. Shirley C. Weiland A. K. Rumaiz C. A. Cardot J. J. Kas J. J. Rehr Material Measurement Science Division Material Measurement Laboratory National Institute of Standards and Technology Gaithersburg Maryland 20899 USA Sensor Science Division Physical Measurement Laboratory National Institute of Standards and Technology Gaithersburg Maryland 20899 USA National Synchrotron Light Source II Brookhaven National Laboratory Upton New York 11973 USA Department of Physics University of Washington Seattle Washington 98195 USA

Gold and platinum both have the face-centered cubic crystal structure and are considered noble metals, yet they differ by one in atomic number. Near-edge M4,5 x-ray absorption and resonant M4,5N6,7N6,7 Auger spectra reveal “dark” edges and a photon-energy dependence of Auger electron (4f12 final-state) energy distributions. These findings are a direct consequence of the delayed onset of d→f transitions and space quantization of the 3d core hole prepared by photoexcitation that is predominantly d→p vs d→f near the edge, in agreement with theoretical predictions. This study showcases the centrifugal barrier for f-wave electrons and spectral evolution arising from the existence of multiple intermediate-state channels and final states for both photoexcitation and Auger decay.

关键词： Density of states Zeeman effect Noble metals Transition metals Auger electron spectroscopy Photoexcitation X-ray absorption near-edge spectroscopy

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Biodegradable additive manufactured ferroelectret as mechanical sensor

Biodegradable additive manufactured ferroelectret as mechani...

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IEEE sensorS

作者： Omar Ben Dali Sergey Zhukov Claas Hartman Heinz von Seggern Gerhard M. Sessler Mario Kupnik Measurement and Sensor Technology Group Technical University of Darmstadt Germany Electronic Materials Technical University of Darmstadt Germany Institute for Telecommunications Technology Technical University of Darmstadt Germany

Ferroelectrets are piezoelectric polymers, typically cellular polymer foams that exhibit a large piezoelectric response. In this work, we present a biodegradable 3D printed ferroelectret using Fused Deposition Modeling (FDM). Even though the charging process of the ferroelectret is conducted at room temperature, the printed PLA exhibits good charge stability over 150 days at this temperature. A distinctive feature of the manufactured ferroelectret is that its mechanical properties mainly depend on its geometry, offering the possibility for it to be softer than the printed material itself. In fact, the investigated geometry in this paper exhibits a Young’s modulus of 0.5 kPa for stresses under 1 kPa. An excellent piezoelectric coefficient of 600 pC/N was recorded, which is comparable with the well known polypropylene ferroelectret. The presented ferroelectret is suitable for various mechanical sensor application.

关键词： Mechanical sensors Geometry Solid modeling Temperature Three-dimensional displays Programmable logic arrays Stability analysis

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