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Annual IEEE Conference on Applied Power Electronics Conference and Exposition (APEC)

作者： Fang Luo Shuo Wang Fred Wang Dushan Boroyevich Nicolas Gazel Yong Kang College of Electrical and Electric Engineering Huazhong University of Science and Technology Wuhan China Center of Power Electronics Systems Virginia Polytechnic Institute and State University Blacksburg VA USA Electrical Power Systems GE Aviation Systems Vandalia OH USA Department of Electrical Engineering and Computer Science Oak Ridge National Laboratory University of Tennessee Knoxville TN USA Virginia Polytechnic Institute and State University United States

Common mode (CM) choke saturation is a practical problem in common-mode filter applications. It's generally believed that the leakage inductance of common-mode chokes makes the core saturated. This paper analyzes two new mechanisms for common-mode choke saturation due to common-mode voltage, and these mechanisms are verified in experiment. Common-mode choke saturation is particularly important for motor drive systems, which have a high common-mode voltage and comparably higher stray grounding capacitance. A model is established to describe the relationship between the common-mode voltage and the volume of the common-mode magnetic components. According to the analysis, LISNs (line impedance stabilization networks) play an important role in the design of CM magnetic components.

关键词： Voltage Motor drives Electromagnetic interference Inductors Filters Saturation magnetization Inductance Grounding Capacitance Magnetic analysis

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Time-optimal trajectories for a robot manipulator: a provably good approximation algorithm

Time-optimal trajectories for a robot manipulator: a provabl...

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IEEE International Conference on Robotics and Automation (ICRA)

作者： G. Heinzinger P. Jacobs J. Canny B. Paden Department of Electrical Engineering and Computer Sciences and the Electronics Research Laboratory University of California Berkeley Berkeley CA USA Laboratoire d'Automatique et d'Analyse des Systemes Toulouse France Department of Computer Science University of California Berkeley CA USA Department of Mechanical Engineering and Center for Robotic Systems in Microelectronics University of California슠Santa Barbara Santa Barbara CA USA

An algorithm is presented for generating near-time-optimal trajectories for an open-kinematic-chain manipulator moving in a cluttered workspace. This is the first algorithm to guarantee bounds on the closeness of an approximation to a time-optimal trajectory. The running time and space required are polynomial in the desired accuracy of the approximation. The user may also specify tolerances by which the trajectories must clear obstacles in the workspace to allow modeling of control errors.< >

关键词： Robots Manipulators Approximation algorithms Optimized production technology Safety

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On the viability of energy harvesting piezoelectric devices for supplemental power generation in uninhabited aircraft systems

On the viability of energy harvesting piezoelectric devices ...

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AIAA Modeling and Simulation Technologies Conference 2014

作者： Feiguel, Arnaud Ricks, Trenton M. McWilliams, Keith Lacy, Thomas E. Myers, Oliver Donohoe, J. Patrick Jha, Ratan Sullivan, Rani W. Department of Machines Mechanisms Systems French Institute of Advanced Mechanics Clermont-Ferrand France Department of Aerospace Engineering Mississippi State University Mail Stop 9549 MSMS 39762 United States Department of Mechanical Engineering Mississippi State University Mail Stop 9549 MSMS 39762 United States Department of Electrical and Computer Engineering Mississippi State University Mail Stop 9549 MSMS 39762 United States Raspet Flight Research Laboratory Mississippi State University 114 Airport Rd StarkvilleMSMS 39762 United States Department of Aerospace Engineering Mississippi State University Mail Stop 9549 MSMS 39762 United States

ISBN: (数字)9781624103186

ISBN: (纸本)9781624102974

In this work, a global air vehicle finite element model employing empirically determined cyclic loads is used to assess the viability of energy harvesting piezoelectric devices for supplemental power generation in lightweight uninhabited aircraft systems (UASs) where the "Owl" all-composite ultralight UAS is used as a candidate proof-of-concept platform. The Owl was developed at the Mississippi State University Raspet Flight Research laboratory as part of the U.S. Army Space Missile Defense Command High Performance Materials/Processes (HIPERMAP) Program. In the HIPERMAP flight test program, strain-time histories were recorded at key locations throughout the wing and fuselage. These measured strains were used in the investigation of practical implementation of energy harvesting piezoelectric materials within the Owl UAS with the intent of harvesting electrical power from structural oscillations of the wings during operation. The total power generated was determined from a 80 KIAS 4G pullup maneuver, where piezoelectric patches were simulated in the span-wise direction along the inner surfaces of the upper and lower skins of both wings. The energy harvesting capability of the Owl UAS was insufficient due to the small oscillation frequency and low strain magnitudes of the wing during flight. Nevertheless, such energy harvesting devices remain promising for microscale UASs where power requirements are lower and the oscilation frequency of the wings is higher. © 2014 by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved.

关键词： Piezoelectricity

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Automatic face region tracking for highly accurate face recognition in unconstrained environments

Automatic face region tracking for highly accurate face reco...

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IEEE Conference on Advanced Video and Signal Based Surveillance (AVSS)

作者： Y.-O. Kim J. Paik Jingu Heo A. Koschan B. Abidi M. Abidi Korea Electronics and Technology Institute Puchon Gyeonggi South Korea Image Processing Laboratory Department of Image Engineering Graduate School of Advanced Imaging Science Multimedia and Film Chung-Ang University Seoul South Korea Imaging Robotics and Intelligent Systems Laboratory Department of Electrical and Computer Engineering University of Tennessee Knoxville USA

We present a combined real-time face region tracking and highly accurate face recognition technique for an intelligent surveillance system. High-resolution face images are very important to achieving accurate identification of a human face. Conventional surveillance or security systems, however, usually provide poor image quality because they use only fixed cameras to record scenes passively. We have implemented a real-time surveillance system that tracks a moving face using four pan-tilt-zoom (PTZ) cameras. While tracking, the region-of-interest (ROI) can be obtained by using a low-pass filter and background subtraction with the PTZ. Color information in the ROI is updated to extract features for optimal tracking and zooming. FaceIt/sup /spl reg//, which is one of the most popular face recognition software packages, is evaluated and then used to recognize the faces from the video signal. Experimentation with real human faces showed highly acceptable results in the sense of both accuracy and computational efficiency.

关键词： Face recognition Surveillance Real time systems Humans Cameras Intelligent systems Security Image quality Layout Low pass filters

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Autonomous nanorobots with powerful thrust under dry solid-contact conditions by photothermal shock

Research Square

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Research Square 2023年

作者： Gu, Zhaoqi Zhu, Runlin Shen, Tianci Dou, Lin Liu, Hongjiang Liu, Yifei Liu, Xu Liu, Jia Zhuang, Songlin Gu, Fuxing Laboratory of Integrated Opto-Mechanics and Electronics Shanghai Key Laboratory of Modern Optical System School of Optical-Electrical and Computer Engineering University of Shanghai for Science and Technology Shanghai200093 China State Key Laboratory of Reliability and Intelligence of Electrical Equipment Hebei University of Technology Tianjin300130 China Department of Industrial and Systems Engineering Auburn University AuburnAL36849 United States

Nanorobotic motion on solid substrates is greatly hindered by strong nanofriction, and powerful nanomotors‒the core components for nanorobotic motion‒are still lacking. Optical actuation addresses power and motion control issues simultaneously, while conventional technologies with small thrust usually apply to fluid environments. Here, we demonstrate micronewton-thrust nanomotors that enable the autonomous nanorobots working like conventional robots with precise motion control on dry surfaces by a photothermal-shock technique. We build a pulsed laser-based actuation and trapping platform, termed photothermal-shock tweezers, for general motion control of metallic nanomaterials and assembled nanorobots with nanoscale precision. The thrust-to-weight ratios up to 107 enable nanomotors output forces to interact with external micro/nano-objects. Leveraging machine vision and deep learning technologies, we assemble the nanomotors into autonomous nanorobots with complex structures, and demonstrate multi-degree-of-freedom motion and sophisticated functions. Our photothermal shock-actuation concept fundamentally addresses the nanotribology challenges and expands the nanorobotic horizon from fluids to dry solid surfaces. © 2023, CC BY.

关键词： Nanorobotics

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A cost-benefit analysis of transmission network reinforcement driven by generation capacity expansion

A cost-benefit analysis of transmission network reinforcemen...

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IEEE General Meeting Power& Energy Society

作者： Antonis Papaemmanouil Le Anh Tuan Göran Andersson Lina Bertling Filip Johnsson Power Systems Laboratory of Electrical and Computer Engineering (Swiss Federal Institute of Technology) ETH Zurich Switzerland Division of Electric Power Engineering Department of Energy and Environment Chalmers University of Technology Gothenburg Sweden Energy and Technology division Chalmers University of Technology Gothenburg Sweden

This paper assesses the effects of the future European power generation system with strict CO 2 emission reduction targets on the planning of cross-border interconnection lines. Results from a techno-economic energy systems model have been used as input to this work, regarding the development of the European power generation system until the year 2050, meeting the EU 2020 CO 2 target and a 85% emissions reduction until the year 2050. A simplified UCTE power system model was developed in order to analyze how the cross-border interconnections in continental Europe are affected by the generation plans using an iterative method. The paper also attempts to identify the congestion points and proposes solutions based on nodal price modeling. A cost-benefit analysis (CBA) is used to evaluate the appropriate transmission planning strategy, with the costs being the long-term investment costs and the benefits being both the avoided environmental costs and the total congestion costs. The effects of new investments on the nodal prices are also studied. The results show that the profitability of the investments is influenced by the available production mix and the forecasted CO 2 prices. The avoided congestion costs participate rather insignificantly in the CBA, which means that congestions are not relieved, showing that many interconnections are insufficient for nodal pricing market structure.

关键词： Planning Power generation Investments Production Europe Power transmission lines Electricity

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Plasma effects in lateral Schottky junction tunneling transit-time terahertz oscillator

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Journal of Physics: Conference Series 2006年第1期38卷 228-233页

作者： Ryzhii, V. Satou, A. Khmyrova, I. Ryzhii, M. Otsuji, T. Mitin, V. Shur, M.S. Computer Solid State Physics Laboratory University of Aizu Aizu-Wakamatsu 965-8580 Japan Research Institute of Electric Communication Tohoku University Sendai 980-8577 Japan Department of Electrical Engineering University at Buffalo SUNY NY 14260 United States Department of Electrical Computer and Systems Engineering Rensselaer Polytechnic Institute Troy NY 12180 United States

We study the plasma oscillations in a two-dimensional electron channel with a reverse-biased Schottky junction. Using the developed model we show that the negative dynamic conductivity of the Schottky junction associated with the tunneling injection and electrontransit- time effect can result in the self-excitation of plasma oscillations (plasma instability) in the quasineutral portion of the channel serving as a resonant cavity. The spectrum of plasma oscillations and the conditions of their self-excitations are expressed via the structure parameters. The instability can be used in a novel diode device - lateral Schottky junction tunneling transit-time terahertz oscillator. © 2006 IOP Publishing Ltd.

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Carbon-Aware Computing in a Network of Data Centers: A Hierarchical Game-Theoretic Approach

arXiv

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arXiv 2024年

作者： Breukelman, Enno Hall, Sophie Belgioioso, Giuseppe Dörfler, Florian The KTH Royal Institute of Technology School of Electrical Engineering and Computer Science Division of Decision and Control Systems Malvinas väg 10 StockholmSE-100 44 Sweden The Automatic Control Laboratory Department of Electrical Engineering and Information Technology ETH Zurich Physikstrasse 3 Zürich8092 Switzerland

Over the past decade, the continuous surge in cloud computing demand has intensified data center workloads, leading to significant carbon emissions and driving the need for improving their efficiency and sustainability. This paper focuses on the optimal allocation problem of batch compute loads with temporal and spatial flexibility across a global network of data centers. We propose a bilevel game-theoretic solution approach that captures the inherent hierarchical relationship between supervisory control objectives, such as carbon reduction and peak shaving, and operational objectives, such as priority-aware scheduling. Numerical simulations with real carbon intensity data demonstrate that the proposed approach successfully reduces carbon emissions while simultaneously ensuring operational reliability and priority-aware scheduling. © 2024, CC BY-NC-ND.

关键词： Carbon

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Hybrid surface waves in twisted anisotropic heterometasurfaces

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Physical Review Applied 2024年第6期21卷 064034-064034页

作者： Xinyan Zhang Chenxu Bian Zheng Gong Ruoxi Chen Tony Low Hongsheng Chen Xiao Lin Interdisciplinary Center for Quantum Information State Key Laboratory of Extreme Photonics and Instrumentation International Joint Innovation Center The Electromagnetics Academy at Zhejiang University Department of Electrical and Computer Engineering Key Lab. of Advanced Micro/Nano Electronic Devices & Smart Systems of Zhejiang Jinhua Institute of Zhejiang University Shaoxing Institute of Zhejiang University

Recent advances in twisted photonic structures (e.g., twisted bilayer graphene and twisted anisotropic metasurfaces) have enabled many exotic phenomena of light-matter interactions, such as topological transition of the isofrequency contour of surface waves at the magic angle, photonic flatbands, and localization-to-delocalization transition of light. In general, the optical features of these twisted photonic structures are sensitive to the interlayer twist angle. Here we investigate the mode hybridization of surface waves supported by twisted bilayer anisotropic heterometasurfaces, whose two constituent metasurfaces are nonidentical and support surface waves with similar spatial confinements but distinct polarizations. Counterintuitively, we find that the shape of the isofrequency contour of these hybrid surface waves—eigenmodes with both transverse magnetic and transverse electric wave components—can be insensitive to the twist angle, due to the weak interlayer electromagnetic coupling. Moreover, the interlayer distance provides a unique route to reshape the dispersion of one specific kind of hybrid surface wave, while it has negligible influence on the other kinds. Our finding enriches the physics of light-matter interactions in twisted photonic structures and may open new possibilities to mold the flow of light at the subwavelength scale.

关键词： Classical optics Light-matter interaction Metamaterials Metasurfaces Near-field optics Photonics Plasmonics Van der Waals interaction

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Abel transforms relating Kerr effect optical phase shifts and axisymmetric electric field distributions

Abel transforms relating Kerr effect optical phase shifts an...

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Conference on electrical Insulation and Dielectric Phenomena, (CEIDP)

作者： M. Zahn P. Atten B. Malraison Department of Electrical Engineering and Computer Science Laboratory for Electromagnetic and Electronic Systems Massachusetts Institute of Technology Cambridge MA USA Laboratoire DElectrostatique et de Materiaux Dielectriques Centre National de la Recherche Scientifique (CNRS) Grenoble France

Electric field distributions measured using the Kerr effect cause a phase shift between light components polarized parallel and perpendicular to the electric field, proportional to the magnitude squared of the electric field components in the plane perpendicular to light propagation integrated over the light path length. An attempt is made to recover the electric field distribution from measurements of light phase shifts. For axisymmetric geometries where the electric field depends only on the radial coordinate and whose direction is constant along the light path, as is the case along a planar electrode, the total phase shift for light propagating at a constant distance from the center of symmetry and the electric field distribution are related by an Abel transform pair, a special case of Radon transforms typically used in image reconstructions with medical tomography and holography.< >

关键词： Kerr effect Nonlinear optics Holography Electric variables measurement Phase measurement Optical propagation Biomedical optical imaging Holographic optical components Length measurement Optical polarization

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