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A distributed high-density resistivity meter working on a two-wire cable

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Journal of Physics: Conference Series 2021年第1期1754卷

作者： Xiquan Dong Wang Luo Hongpeng Wang Jian Ge Huan Liu Haobin Dong School of Automation China University of Geosciences Wuhan Hubei 430074 China Hubei Key Laboratory of Advance Control and Intelligent Automation for Complex Systems Wuhan Hubei 430074 China Engineering Research Center of Intelligent Technology for Geo-Exploration Ministry of Education Wuhan Hubei 430074 China

High-density resistivity meter is a common instrument used in shallow geophysical exploration. At present, the structure of the centralized high-density resistivity meter is bulky, while the distributed instrument needs more than 7 core cables, and the long measuring line needs to relay power supply to the intelligent electrode to provide enough voltage, so it is not convenient to use in the field. Aiming at the above problems, a new type of distributed high-density meter is developed, which can realize the power supply, communication, and measurement functions of distributed high-density meter and carry out multi-channel measurement through the time-division multiplexing of a two-wire cable and the short-time power supply of supercapacitor. Finally, the performance of the instrument was verified by experiments.

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Transforming heat transfer with thermal metamaterials and devices

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arXiv 2020年

作者： Li, Ying Li, Wei Han, Tiancheng Zheng, Xu Li, Jiaxin Li, Baowen Fan, Shanhui Qiu, Cheng-Wei Department of Electrical and Computer Engineering National University of Singapore Singapore117583 Singapore Interdisciplinary Center for Quantum Information State Key Laboratory of Modern Optical Instrumentation College of Information Science and Electronic Engineering Zhejiang University Hangzhou310027 China ZJU-Hangzhou Global Science and Technology Innovation Center Key Lab. of Advanced Micro/Nano Electronic Devices & Smart Systems of Zhejiang Zhejiang University Hangzhou310027 China Department of Electrical Engineering Ginzton Laboratory Stanford University StanfordCA94305 United States National Engineering Research Center of Electromagnetic Radiation Control Materials State Key Laboratory of Electronic Thin Film and Integrated Devices University of Electronic Science and Technology of China Chengdu610054 China Department of Physics University of Colorado BoulderCO80309 United States School of Mechatronics Engineering Harbin Institute of Technology Harbin150001 China Paul M. Rady Department of Mechanical Engineering University of Colorado BoulderCO80309 United States

| The demand for sophisticated tools and approaches in heat management and control has triggered fast development of emerging fields including conductive thermal metamaterials, nanophononics, far-field and near-field radiative thermal management, etc. In this review, we cast a unified perspective on the control of heat transfer, based on which the related studies can be considered as complementary paradigms toward manipulating physical parameters and realizing unprecedented phenomena in heat transfer using artificial structures, such as thermal conductivity in heat conduction, thermal emissivity in radiation, and properties related to multi-physical effects. The review is divided into three parts that focus on the three main categories of heat flow control, respectively. Thermal conduction and radiation are emphasized in the first and second parts at both macro- and micro-scale. The third part discusses the efforts to actively introduce heat sources or tune the material parameters with multi-physical effects in both conduction and radiation, including works using thermal convection. We conclude the review with challenges in this research topic and new possibilities about topological thermal effects, heat waves, and quantum thermal effects. Copyright © 2020, The Authors. All rights reserved.

关键词： Metamaterials

Quantum tomography by regularized linear regression

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arXiv 2019年

作者： Mu, Biqiang Qi, Hongsheng Petersen, Ian R. Shi, Guodong Key Laboratory of Systems and Control Institute of Systems Science Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing100190 China Research School of Electrical Energy and Materials Engineering Australian National University Canberra0200 Australia Australian Center for Field Robotics School of Aerospace Mechanical and Mechatronic Engineering University of Sydney 2008 Australia

In this paper, we study extended linear regression approaches for quantum state tomography based on regularization techniques. For unknown quantum states represented by density matrices, performing measurements under certain basis yields random outcomes, from which a classical linear regression model can be established. First of all, for complete or over-complete measurement bases, we show that the empirical data can be utilized for the construction of a weighted least squares estimate (LSE) for quantum tomography. Taking into consideration the trace-one condition, a constrained weighted LSE can be explicitly computed, being the optimal unbiased estimation among all linear estimators. Next, for general measurement bases, we show that '2-regularization with proper regularization gain provides even lower mean-square error under a cost in bias. The regularization parameter is tuned by two estimators in terms of a risk characterization. Finally, a concise and unified formula is established for the regularization parameter with complete measurement basis under an equivalent regression model, which proves that the proposed tuning estimators are asymptotically optimal as the number of samples grows to infinity under the risk metric. Additionally, numerical examples are provided to validate the established results. Copyright © 2019, The Authors. All rights reserved.

关键词： Tomography

Research on three-phase four-leg matrix converter based more electric aircraft wing ice protection system

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Research on three-phase four-leg matrix converter based more...

作者： Huang, Songtao Xu, Lie Guo, Yougui Li, Yongdong Deng, Wenlang School of Information and Engineering Xiangtan University Xiangtan China State Key Laboratory of Control and Simulation of Power Systems and Generation Equipments Tsinghua University Beijing China

In this study, a new three-phase four-leg matrix converter (TFMC) topology is proposed, and the three-dimensional space vector modulation (3DSVM) strategy is used to realise the output with the three-phase unbalanced load. Aiming at the situation that the icing area of the more electric aircraft on the wing is larger than the icing area in the belly, wing ice protection system is constructed by using the TFMC. Through the real-time detection of the heating element temperature and icing condition by the sensor installed in the wing and belly position, working temperature and three-phase output power of TFMC can be set reasonably. In order to save fuel consumption and reduce operating costs, the key point is to reduce the power transmission in belly position. Finally, simulation and experiment verify the correctness of the proposed 3DSVM strategy and realise the TFMC output with unbalanced three-phase load. © 2018 Institution of engineering and Technology. All rights reserved.

关键词： Matrix converters

measurement-induced boolean dynamics and controllability for quantum networks

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arXiv 2019年

作者： Qi, Hongsheng Muy, Biqiang Petersenz, Ian R. Shix, Guodong Key Laboratory of Systems and Control Institute of Systems Science Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing100190 China Research School of Electrical Energy and Materials Engineering Australian National University Canberra0200 Australia Australian Center for Field Robotics School of Aerospace Mechanical and Mechatronic Engineering University of Sydney NSW2008 Australia

In this paper, we study dynamical quantum networks which evolve according to Schrodinger equations but subject to sequential local or global quantum measurements. A network of qubits forms a composite quantum system whose state undergoes unitary evolution in between periodic measurements, leading to hybrid quantum dynamics with random jumps at discrete time instances along a continuous orbit. The measurements either act on the entire network of qubits, or only a subset of qubits. First of all, we reveal that this type of hybrid quantum dynamics induces probabilistic Boolean recursions representing the measurement outcomes. With global measurements, it is shown that such resulting Boolean recursions define Markov chains whose state-transitions are fully determined by the network Hamiltonian and the measurement observables. Particularly, we establish an explicit and algebraic representation of the underlying recursive random mapping driving such induced Markov chains. Next, with local measurements, the resulting probabilistic Boolean dynamics is shown to be no longer Markovian. The state transition probability at any given time becomes dependent on the entire history of the sample path, for which we establish a recursive way of computing such non-Markovian probability transitions. Finally, we adopt the classical bilinear control model for the continuous Schrodinger evolution, and show how the measurements affect the controllability of the quantum networks. Copyright © 2019, The Authors. All rights reserved.

关键词： Quantum optics

Spatial-temporal fusion convolutional neural network for simulated driving behavior recognition

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arXiv 2018年

作者： Hu, Yaocong Lu, MingQi Lu, Xiaobo School of Automation Southeast University Nanjing210096 China Key Laboratory of Measurement and Control of Complex Systems of Engineering Ministry of Education Nanjing210096 China

Abnormal driving behaviour is one of the leading cause of terrible traffic accidents endangering human life. Therefore, study on driving behaviour surveillance has become essential to traffic security and public management. In this paper, we conduct this promising research and employ a two stream CNN framework for video-based driving behaviour recognition, in which spatial stream CNN captures appearance information from still frames, whilst temporal stream CNN captures motion information with pre-computed optical flow displacement between a few adjacent video frames. We investigate different spatial-temporal fusion strategies to combine the intra frame static clues and inter frame dynamic clues for final behaviour recognition. So as to validate the effectiveness of the designed spatial-temporal deep learning based model, we create a simulated driving behaviour dataset, containing 1237 videos with 6 different driving behavior for recognition. Experiment result shows that our proposed method obtains noticeable performance improvements compared to the existing methods. Copyright © 2018, The Authors. All rights reserved.

关键词： Convolution

Wind Farm Equivalent Model Based on Power Output Sensitivity of Wind Turbines

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Wind Farm Equivalent Model Based on Power Output Sensitivity...

Sustainable Power and Energy Conference (iSPEC)

作者： Li Yan Chi Yongning Tang Haiyan Tian Xinshou Chang Yuanzhu China State Key Laboratory of Operation and Control of Renewable Energy & Storage Systems China Electric Power Research Institute Beijing China School of Electrical and Electronic Engineering Huazhong University of Science and Technology Wuhan China

ISBN: (纸本)9781728149318

In general, a wind farm composed of a wind turbine can control the exchange of reactive power between its wind farm outlet and the grid, that is, the entire wind farm does not emit or consume reactive power. Therefore, the reactive power loss of the wind farm of the doubly-fed wind turbine is only the reactive load of the system. Compared with the wind farm of the asynchronous wind turbine, the reactive power consumption of the wind farm of the doubly-fed wind turbine becomes smaller, and the voltage stability is obvious. Better than asynchronous wind turbine wind farms, the reactive power voltage control ability of the grid is weaker than that of synchronous generators. Therefore, when a part of the wind power in the power grid replaces the thermal power generation, the voltage stability of the power grid will be reduced, and the degree of reduction will depend on the reactive power reserve of the thermal power unit in the power grid. In this paper, the wind turbine is connected to the power grid as the research object. According to the voltage characteristics analysis after the wind power is connected to the power grid, the electrical characteristics and its influence in the wind farm are studied. Based on this, the equivalence modeling of the wind farm is proposed.

关键词： Wind Farm Equivalent Model Power Output Sensitivity Wind Turbines Wind farms Wind Energy Conversion systems Power grids Voltage stability Reactive power Wind energy

An Active and Adaptive Image Enhancement Method for Applications in Low-Light and Narrow Environment

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An Active and Adaptive Image Enhancement Method for Applicat...

Chinese Automation Congress (CAC)

作者： Mingrui Luo En Li Rui Guo Shengchuan Li Cunfeng Kang The State Key Laboratory of Management and Control for Complex Systems Institute of Automation Chinese Academy of Sciences Beijing China School of Artificial Intelligence University of Chinese Academy of Sciences Beijing China State Grid Shandong Electric Power Company Jinan China State Grid Liaoning Electric Power Company Limited Shenyang China Mechanical engineering and Applied Electronic Technology Beijing University of Technology Beijing China

ISBN: (数字)9781728176871

ISBN: (纸本)9781728176888

The images in the low-light and narrow environment generally have the problems of non-uniform illumination, low contrast, and large random noise. Existing algorithms are mostly subject to the imaging effect of the original image, and are prone to failure in extremely weak light or strong reflective environments. This paper proposes an active and adaptive image enhancement method. First of all, this paper combines the distributed light source model and the difference in brightness between frames to complete active feedback fill light, which improves the quality of the input image. Then gamma correction, contrast limited adaptive histogram equalization and bilateral filter are designed to enhance image details and suppress noise amplification. Combined with fuzzy inference parameter self-adjustment method, algorithm adaptability is improved. Finally, through experimental verification, the method proposed in this paper can effectively enhance the images in the low-light and narrow environment.

关键词： Light sources Histograms Adaptive equalizers Filtering algorithms Brightness Image color analysis Image enhancement

measurement-Induced boolean dynamics for open quantum networks

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arXiv 2019年

作者： Qi, Hongsheng Mu, Biqiang Petersen, Ian R. Shi, Guodong Key Laboratory of Systems and Control Institute of Systems Science Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing100190 China Research School of Electrical Energy and Materials Engineering Australian National University Canberra0200 Australia Australian Center for Field Robotics School of Aerospace Mechanical and Mechatronic Engineering University of Sydney NSW2008 Australia

In this paper, we study the recursion of measurement outcomes for open quantum networks under sequential measurements. Open quantum networks are networked quantum subsystems (e.g., qubits) with the state evolutions described by a continuous Lindblad master equation. When measurements are performed sequentially along such continuous dynamics, the quantum network states undergo random jumps and the corresponding measurement outcomes can be described by a vector of probabilistic Boolean variables. The induced recursion of the Boolean vectors forms a probabilistic Boolean network. First of all, we show that the state transition of the induced Boolean networks can be explicitly represented through realification of the master equation. Next, when the open quantum dynamics is relaxing in the sense that it possesses a unique equilibrium as a global attractor, structural properties including absorbing states, reducibility, and periodicity for the induced Boolean network are direct consequences of the relaxing property. Particularly, we show that generically, relaxing quantum dynamics leads to irreducible and aperiodic chains for the measurement outcomes. Finally, we show that for quantum consensus networks as a type of non-relaxing open quantum network dynamics, the communication classes of the measurement-induced Boolean networks are encoded in the quantum Laplacian of the underlying interaction graph. Copyright © 2019, The Authors. All rights reserved.

关键词： Quantum theory