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The Method for Evaluating the Reclosing Time of Reclosure Based on Lightning Parameters

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The Method for Evaluating the Reclosing Time of Reclosure Ba...

2017 International Conference on Mechanical and Mechatronics engineering(ICMME2017)

作者： Gun YANG Zhan-qing YU Hong-jun ZHEN Chao SU Shui-ming CHEN Rong ZENG Jin-liang HE State Key Lab.of Control and Simulation of Power Systems and Generation Equipment Department of Electrical EngineeringTsinghua University Qingyuan Power Supply Bureau of Guangdong Grid Company

The fault of transmission line is mostly caused by lightning,and a ground lightning stroke process is often accompanied by multiple *** duration of ground lightning stroke are also *** this paper,a method for evaluating the reclosing time of reclosure based on lightning parameters is *** addition,this paper also gives an expression for the cumulative rate of the duration of ground lightning stroke,and an expression for probability distribution of the amplitude of lightning current in Guangdong *** also proposed a method for calculating the probability of tripping of *** this calculating method,the average probability of tripping of reclosure is less than 1/10000 during a ground lightning stroke process,when the reclosing time t0 is greater than 1.012 s.

关键词： Ground lightning stroke Lightning parameters Reclosing time of reclosure Probability of tripping of reclosure

PSSE Redux: Convex relaxation, decentralized, robust, and dynamic approaches

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arXiv 2017年

作者： Kekatos, Vassilis Wang, Gang Zhu, Hao Giannakis, Georgios B. Bradley Department of Electrical and Computer Engineering Virginia Tech BlacksburgVA24061 United States Department of Electrical and Computer Engineering University of Minnesota MinneapolisMN55455 United States State Key Lab of Intelligent Control and Decision of Complex Systems Beijing Institute of Technology Beijing100081 China Department of Electrical and Computer Engineering University of Illinois UrbanaIL61801 United States

Distributionally robust games: F-divergence and learning

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arXiv 2017年

作者： Bauso, Dario Gao, Jian Tembine, Hamidou Department of Automatic Control and Systems Engineering The University of Sheffield Mappin Street S1 3JD Sheffield United Kingdom Learning & Game Theory Laboratory New York University Abu Dhabi

In this paper we introduce the novel framework of distributionally robust games. These are multi-player games where each player models the state of nature using a worst-case distribution, also called adversarial distribution. Thus each player’s payoff depends on the other players’ decisions and on the decision of a virtual player (nature) who selects an adversarial distribution of scenarios. This paper provides three main contributions. Firstly, the distributionally robust game is formulated using the statistical notions of f-divergence between two distributions, here represented by the adversarial distribution, and the exact distribution. Secondly, the complexity of the problem is significantly reduced by means of triality theory. Thirdly, stochastic Bregman learning algorithms are proposed to speedup the computation of robust equilibria. Finally, the theoretical findings are illustrated in a convex setting and its limitations are tested with a non-convex non-concave function. Copyright © 2017, The Authors. All rights reserved.

关键词： Stochastic systems

Learning sparse graphs for prediction of multivariate data processes

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arXiv 2017年

作者： Venkitaraman, Arun Zachariah, Dave Department of Information Science and Engineering School of Electrical Engineering and Computer Science KTH Royal Institute of Technology StockholmSE-100 44 Sweden Department of Information Technology Division of Systems and Control Uppsala University UppsalaSE- 752 37 Sweden

We address the problem of prediction of multivariate data process using an underlying graph model. We develop a method that learns a sparse partial correlation graph in a tuning-free and computationally efficient manner. Specifically, the graph structure is learned recursively without the need for cross-validation or parameter tuning by building upon a hyperparameter-free framework. Our approach does not require the graph to be undirected and also accommodates varying noise levels across different nodes. Experiments using real-world datasets show that the proposed method offers significant performance gains in prediction, in comparison with the graphs frequently associated with these datasets. Copyright © 2017, The Authors. All rights reserved.

关键词： Forecasting

On the dynamics of deterministic epidemic propagation over networks

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arXiv 2017年

作者： Mei, Wenjun Mohagheghi, Shadi Zampieri, Sandro Bullo, Francesco Department of Mechanical Engineering and Center for Control Dynamical Systems and Computation University of California Santa Barbara Santa BarbaraCA93106 United States Department of Electrical and Computer Engineering University of California at Santa Barbara Santa BarbaraCA93106 United States Department of Information Engineering University of Padova Italy

In this work we review a class of deterministic nonlinear models for the propagation of infectious diseases over contact networks with strongly-connected topologies. We consider network models for susceptible-infected (SI), susceptible-infected-susceptible (SIS), and susceptible-infected-recovered (SIR) settings. In each setting, we provide a comprehensive nonlinear analysis of equilibria, stability properties, convergence, monotonicity, positivity, and threshold conditions. For the network SI setting, specific contributions include establishing its equilibria, stability, and positivity properties. For the network SIS setting, we review a well-known deterministic model, provide novel results on the computation and characterization of the endemic state (when the system is above the epidemic threshold), and present alternative proofs for some of its properties. Finally, for the network SIR setting, we propose novel results for transient behavior, threshold conditions, stability properties, and asymptotic convergence. These results are analogous to those well-known for the scalar case. In addition, we provide a novel iterative algorithm to compute the asymptotic state of the network SIR system. Copyright © 2017, The Authors. All rights reserved.

关键词： Nonlinear dynamical systems

Handling Missing Data in Multivariate Time Series Using a Vector Autoregressive Model Based Imputation (VAR-IM) Algorithm. Part II: VAR-IM Algorithm Versus Modern Methods 19

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Handling Missing Data in Multivariate Time Series Using a Ve...

19th IEEE International Conference on Computational Science and engineering, 14th IEEE International Conference on Embedded and Ubiquitous Computing and 15th International Symposium on Distributed Computing and Applications to Business, engineering and Science, CSE-EUC-DCABES 2016

作者： Bashir, Faraj Wei, Hua-Liang University of Sheffield Department of Automatic Control and Systems Engineering Mapping Street SheffieldS1 3JD United Kingdom

ISBN: (纸本)9781509035939

This part of the paper introduces a comparison of VAR-IM algorithm with modern techniques used for missing data analysis. Quantitative methods are usually developed based on some fundamental understanding of the statistical analysis of the missing data. Various types of quantitative methods such as K nearest neighbour (KNN), (Multivariate Autoregressive state-Space) MARRS package and EM algorithm are discussed. The relative advantages and disadvantages of these approaches are highlighted. The performance of the vector autoregressive model based imputation methods is compared with that of three existing methods, namely, KNN, MARRRS and EM for dealing with missing data in multivariate time series, where an ECG dataset is used as an a case study. The results show that VAR-IM produces a better recovering performance for missing values than the other three methods. The advantages and limitations of the VAR-IM algorithm is also discussed. © 2016 IEEE.

关键词： Electrocardiograms

Design of Low-cost Position Differential Positioning System Based on STM32

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Design of Low-cost Position Differential Positioning System ...

Chinese Automation Congress

作者： Haijun Fu Ming Qiu Xisong Dong Gang Xiong Haonan Xiong Xiang Su Shichao Chen Zhen Shen Xiujiang Guo School of Artificial Intelligence Beijing Union University Beijing China The Cloud Computing Center Chinese Academy of Sciences Dongguan China The Qingdao Academy of Intelligent Industries Macau University of Science and Technology Qingdao China Beijing Union University Beijing China School of Electrical Engineering and Electronic Information Xihua University Chengdu China The State Key Laboratory for Management and Control of Complex Systems Chinese Academy of Sciences Beijing China The Beijing Engineering Research Center of Intelligent Systems and Technology Chinese Academy of Sciences Beijing China Department of Computer Science University of Helsinki Fin Finland Measurement Center Station PetroChina Huabei Oilfield Company Renqiu China

There exist some obstacles to realize high-precision positioning with using the position differential technique due to the limiting factors. However, with the advancement of chip performance and the establishment of multiple satellite navigation systems, position differential positioning can be realized to meet the civilian high-precision positioning demand while significantly reducing costs. This paper is to explore the engineering application and propose a new method. Through the experiments and data analysis, we have found the error correlation between two receivers in a small area and designed a set of positioning system, and programmed in the Keil μVision5 in C language. The system consists of the current mainstream low-cost STM32, UBLOX NEO 6M chip, NRF24L01 chip, GPS antenna and power supply module. Each two receivers can form a differential positioning system. At present, the system in the low-speed status is, in the urban environment, basically reaching within 0.5 - 3 m of the positioning error.

关键词： Position differential positioning Low cost Error correlation GPS STM32

Cryptographic protocol for multipart missions involving two independent and distributed decision levels in a military context

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arXiv 2017年

作者： Fattahi, Jaouhar Mejri, Mohamed Ziadia, Marwa Ghayoula, Elies Samoud, Ouejdene Pricop, Emil Defense Research and Development Canada Valcartier Research Centre Québec Canada Computer Science and Software Engineering Department Laval University Québec Canada Department of Electrical and Computer Engineering Laval University Québec Canada Automatic Control Computers and Electronics Department Petroleum-Gas University of Ploiesti Romania

In several critical military missions, more than one decision level are involved. These decision levels are often independent and distributed, and sensitive pieces of information making up the military mission must be kept hidden from one level to another even if all of the decision levels cooperate to accomplish the same task. Usually, a mission is negotiated through insecure networks such as the Internet using cryptographic protocols. In such protocols, few security properties have to be ensured. However, designing a secure cryptographic protocol that ensures several properties at once is a very challenging task. In this paper, we propose a new secure protocol for multipart military missions that involve two independent and distributed decision levels having different security levels. We show that it ensures the secrecy, authentication, and non-repudiation properties. In addition, we show that it resists against man-in-the-middle attacks. Copyright © 2017, The Authors. All rights reserved.

关键词： Authentication

Flows and magnetic field structures in reconnection regions of simulations of the solar atmosphere: do flux pile-up models work?

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arXiv 2018年

作者： Shelyag, S. Litvinenko, Y.E. Fedun, V. Verth, G. González-Avilés, J.J. Guzmán, F.S. Department of Mathematics Physics and Electrical Engineering Northumbria University Newcastle upon TyneNE1 8ST United Kingdom Department of Mathematics University of Waikato P. B. 3105 Hamilton New Zealand Plasma Dynamics Group Department of Automatic Control and Systems Engineering University of Sheffield SheffieldS1 3JD United Kingdom Plasma Dynamics Group School of Mathematics and Statistics University of Sheffield SheffieldS3 7RH United Kingdom Instituto de Geofísica Unidad Michoacán Universidad Nacional Autónoma de México MoreliaMichoacán Mexico Laboratorio de Inteligencia Artificial y Supercómputo Instituto de Física y Matemáticas Universidad Michoacana de San Nicolás de Hidalgo. MoreliaMichoacán Mexico

Aims. We study the process of magnetic field annihilation and reconnection in simulations of magnetised solar photosphere and chromosphere with magnetic fields of opposite polarities and constant numerical resistivity. Methods. Exact analytical solutions for reconnective annihilations are used to interpret the features of magnetic reconnection in simulations of flux cancellation in the solar atmosphere. We use MURaM high-resolution photospheric radiative magneto-convection simulations to demonstrate the presence of magnetic field reconnection consistent with the magnetic flux pile-up models. Also, a simulated data-driven chromospheric magneto-hydrodynamic simulation is used to demonstrate magnetic field and flow structures, which are similar to the ones theoretically predicted. Results. Both simulations demonstrate flow and magnetic field structures roughly consistent with accelerated reconnection with magnetic flux pile-up. The presence of standard Sweet-Parker type reconnection is also demonstrated in stronger photospheric magnetic fields. Copyright © 2018, The Authors. All rights reserved.

关键词： Magnetic flux