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Research on coal mine safety monitoring data storage based on HBase

Journal of Physics: Conference Series 2020年第1期1693卷

作者： Lizheng Jiang Yanbin Li School of Control and Computer Engineering North China Electric Power University Beijing 102206 China

In order to solve the problem of low storage efficiency and slow query speed when massive coal mine safety monitoring data is stored in relational database, a method of storage and retrieval based on HBase was designed. By combining the hash value of the combination of coal mine code, substation code and transducer code as well as the timestamp after inversion, the hot spot and data skew caused by the unreasonable design of rowkey in HBase were avoided. In order to improve the efficiency of data storage, the swing door trending (SDT) algorithm was used to compress the monitoring data, and in order to improve the efficiency of data retrieval, a secondary index based on ElasticSearch was constructed. The experimental results on the real coal mine data show that the efficiency of data storage and retrieval has been significantly improved.

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On the well-posedness of dynamical flow networks with feedback-controlled outflows

arXiv

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arXiv 2020年

作者： Como, Giacomo Nilsson, Gustav Dipartimento di Scienze Matematiche Politecnico di Torino Corso Duca degli Abruzzi 24 Torino10129 Italy Department of Automatic Control Lund University Sweden School of Electrical and Computer Engineering Georgia Institute of Technology 777 Atlantic Drive NW AtlantaGA United States

We study the well-posedness of a class of dynamical flow network systems describing the dynamical mass balance among a finite number of cells exchanging flow of a commodity between themselves and with the external environment. Systems in the considered class are described as differential inclusions whereby the routing matrix is constant and the outflow from each cell in the network is limited by a control that is a Lipschitz continuous function of the state of the network. In many applications, such as queueing systems and traffic signal control, it is common that an empty queue can be allowed to have more outflow than the mass in the queue. While models for this scenario have previously been presented for open-loop outflow controls, this result ensures the existence and uniqueness of solutions for the network flow dynamics in the case Lipschitz continuous feedback controllers. Copyright © 2020, The Authors. All rights reserved.

关键词： Queueing networks

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Chirality-induced quantum nonreciprocity

arXiv

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arXiv 2025年

作者： Zhang, Zimo Xu, Zhongxiao Huang, Ran Lu, Xingda Zhang, Fengbo Li, Donghao Özdemir, Şahin K. Nori, Franco Bao, Han Xiao, Yanhong Chen, Bing Jing, Hui Shen, Heng State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Opto-electronics Shanxi University Shanxi Taiyuan030006 China Collaborative research center on Quantum optics and extreme optics Shanxi University Shanxi Taiyuan030006 China RIKEN Wakoshi Saitama351-0198 Japan Fudan University Shanghai200433 China Department of Electrical and Computer Engineering Saint Louis University St. LouisMO63103 United States Physics Department The University of Michigan Ann ArborMI48109-1040 United States QUANTUM Johannes Gutenberg-Universität Mainz Mainz55128 Germany School of Physics Hefei University of Technology Anhui Hefei230009 China State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Laser Spectroscopy Shanxi University Shanxi Taiyuan030006 China Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education Department of Physics Synergetic Innovation Center for Quantum Effects and Applications Hunan Normal University Changsha410081 China

Chirality, nonreciprocity, and quantum correlations are at the center of a wide range of intriguing effects and applications across natural sciences and emerging quantum technologies. However, the direct link combining these three essential concepts has remained unknown till now. Here, we establish a chiral non-Hermitian platform with flying atoms and demonstrate chirality-induced nonreciprocal bipartite quantum correlations between two channels: Quantum correlation emerges when two spatially separated light beams of the same polarization propagate in opposite directions in the atomic cloud, and it becomes zero when they travel in the same direction. Thus, just by flipping the propagation direction of one of the beams while keeping its polarization the same as the other beam, we can create or annihilate quantum correlations between two channels. We also show that this nonreciprocal quantum correlation can be extended to multi-color sidebands with Floquet engineering. Our findings may pave the road for realizing one-way quantum effects, such as nonreciprocal squeezing or entanglement, with a variety of chiral devices, for the emerging applications of e.g., directional quantum network or nonreciprocal quantum metrology. © 2025, CC BY.

关键词： Quantum theory

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Primary frequency regulation oriented wind turbines active power dispatching optimization by double-layer flower pollination algorithm

Primary frequency regulation oriented wind turbines active p...

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Chinese Automation Congress (CAC)

作者： Weifeng Liang Congzhi Huang Qiang Guo Zhiwei Xue Liang Tian School of Control and Computer Engineering North China Electric Power University Beijing China State Grid Shanxi Electric Power Research Institute Taiyuan China State Grid Shanxi Electric Power Company Taiyuan China Shanxi Xinwangda Energy Internet Research Institute Taiyuan China

ISBN: (数字)9781728176871

ISBN: (纸本)9781728176888

Due to the volatility, randomness and intermittence of wind energy, which leads to the instability of wind power grid connection frequency. Wind power plants need to have the ability of primary frequency regulation to ensure the safe and stable operation of the grid system. In this paper, a method of wind turbines performance evaluation and power dispatch is proposed. The actual SCADA data are divided into internal evaluation indexes and external evaluation indexes. The performance scores of wind turbines are calculated by using the deteriorative degree, membership function of ridge distribution and independence weight method, and the units are classified. The mathematical model of wind turbines power dispatching is established, and the double-layer flower pollination algorithm is used to optimize the model. Finally, the power dispatching value of each unit is obtained. The results show that the wind turbines power dispatching method in this paper can meet the power grid dispatching instructions, and reduce the damage to the units caused by frequent start and stop of wind turbines.

关键词： Wind turbines Indexes Dispatching Mathematical model Performance evaluation Optimization Wind farms

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Accurate object recognition for unmanned aerial vehicle electric power inspection using an improved YOLOv2 algorithm 4

Accurate object recognition for unmanned aerial vehicle elec...

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4th IEEE International Conference on Data Science in Cyberspace, DSC 2019

作者： Chen, Qiang Gao, Yunyuan Peng, Yun Zhang, Jianhai Sun, Ke Intelligent Control and Robotics Institute Hangzhou Dianzi University Hangzhou China Department of Biomedical Engineering University of Houston Houston United States School of Computer Science and Technology Hangzhou Dianzi University Hangzhou China Hangzhou Chuangjiang Information Technology Co. Ltd. Hangzhou China

ISBN: (纸本)9781728145280

With the growing application of Unmanned Aerial Vehicle (UAV) in the electric power inspection, there is an increasing demand for accurate recognition of power tower components from a large number of pictures and videos. Traditional machine learning methods require feature extraction of, such as edge, color, texture, etc., are not suitable for the complex scene of the UAV electric power inspection. The end-toend object detection algorithm YOLOv2, offers overall high recognition accuracy and speed, but is less so in recognizing small targets. In this study, the YOLOv2 was improved by: 1)adding an additional passthrough layer to the original network to fuse more fine-grained features to improve the recognition capability for small targets, and 2) removing the redundant convolutional layers and reducing the number of the filters in the middle convolutional layers to simplify the network structure. The datasets are from Multi-rotor UAV inspection of high voltage transmission lines. Three types of power tower components including the tower, tower base, and signs are selected as recognition targets. Results showed that the mean average precision (mAP) of the improved model for three types of target recognition was increased to 98.19%, higher than that of the original one, and the recognition speed was increased by 35%. © 2019 IEEE.

关键词： Inspection

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Robust Design of Transmit/Receive Beamforming for Multiple-input Multiple-output Radar

Robust Design of Transmit/Receive Beamforming for Multiple-i...

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2019 IEEE International Conference on Signal, Information and Data Processing, ICSIDP 2019

作者： Qian, Junhui Luo, Yu Fu, Ning Liu, Ran Feng, Zeyu School of Microelectronic and Communication Engineering Chongqing University Chongqing China Harbin Institute of Technology Department of Automatic Test and Control Harbin China College of Computer Science Chongqing University Chongqing China Chengdu Surveying Geotechnical Research Institute Co. Ltd. of MCC Chengdu China

ISBN: (纸本)9781728123455

The transmit/receive robust adaptive beamformer design of a multiple-input multiple-output (MIMO) radar system is studied in this paper. We first construct the interference covariance matrix via a shrink-based approach. Then, the desired transmit-receive steering vector (SV) is estimated through maximizing the output power upon the cooperative constraint and norm constraints under the presumed SV. An iterative procedure is designed to deal with the original nonconvex problem, whose convergence is analytically proven with the estimated SV. Simulation results show the merits of the proposed design in various scenarios. © 2019 IEEE.

关键词： MIMO radar

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Research on Sales Forecast Based on Prophet-SARIMA Combination Model

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Journal of Physics: Conference Series 2020年第1期1616卷

作者： Jiantao Zhao Chunwei Zhang School of Control and Computer Engineering North China Electric Power University Beijing 102206 China

The stable development of e-commerce enterprises cannot be separated from scientific replenishment planning, and forecasting the sales volume of products helps e-commerce to make a reasonable replenishment plan, so as to speed up cash flow and reduce inventory pressure. Based on the in-depth study of Prophet model and seasonal differential autoregressive moving average model, as well as the analysis of daily sales volume of an e-commerce product from January 2015 to March 2018, a Prophet-SARIMA combination model for sales volume prediction is proposed. The principle of the combination model is to use prophet and SARIMA model to forecast the sales data respectively, and then weighted combination to get the final forecast results. Analyze and compare the prediction effect of single model and combination model. The first mock exam shows that the Prophet-SARIMA combination model has higher accuracy and stability in sales volume forecasting than single model. The sales volume forecast results of Prophet SARIMA combination model can provide an important basis for the e-commerce to supplement orders scientifically.

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Design and simulation of an adaptive networked tracking control system

Design and simulation of an adaptive networked tracking cont...

引用

2018 International Conference on Advanced Mechatronic Systems, ICAMechS 2018

作者： Tong, Shiwen Oian, Dianwei Cheng, Guang Beijing100101 China School of Control and Computer Engineering North China Electric Power University Beijing102206 China

ISBN: (纸本)9781538671740

A novel Adaptive Networked Tracking control System (ANTCS) has been proposed in this paper. The system first uses a data-based modeling technology named fuzzy cluster modeling to obtain the T-S fuzzy model of the process. Then, an equivalent fuzzy singleton model is built which satisfies the invertibiity conditions. Thus, the future control actions can be obtained by prediction, iteration and inversion of the fuzzy singleton model. To improve the control performance of the proposed method, an adaptation strategy is implemented by updating the consequent parameters of the fuzzy singleton model and the corresponding inverse model with least-squares algorithm. Radom time delay in the forward channel can be easily compensated by selecting appropriate control actions from the candidate ones which are generated from the networked controller and transmitted from the controller side to the plant side Simulative results demonstrate the effectiveness of this method. © 2018 IEEE.

关键词： controllers

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Improved K-medoids clustering based on gray association rule

Improved K-medoids clustering based on gray association rule

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International Conference on Intelligent Computing, Communication and Devices, ICCD 2017

作者： Gao, Shiying Zhou, Xiaofeng Li, Shuai Shenyang Institute of Automation Chinese Academy of Sciences Shenyang110016 China University of Chinese Academy of Sciences Beijing100049 China Key Laboratory of Network Control System Chinese Academy of Sciences Shenyang110016 China School of Computer Science and Engineering Northeastern University Shenyang110000 China

ISBN: (纸本)9789811089435

This paper presents a new K-Medoids clustering algorithm based on gray relational degree. Analyze the gray incidence of each attribute and convert them into the weights of the attributes, and then apply these weights to the distance measure of the cluster;based on this measure, this paper proposed an improved clustering algorithm: Gray-K-Medoids clustering algorithm and applied it to the analysis of the aluminum electrolysis data. The paper introduces the gray relational degree and the basic principle based on the gray relational degree clustering and introduced the improved algorithm in detail. In order to test the effect of improving the algorithm, it was used to the production data of an aluminum plant, and the results show the effectiveness of the algorithm, has a certain promotional value. © Springer Nature Singapore Pte Ltd. 2019.

关键词： Clustering algorithms

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State-control-limit-based rejuvenation modelling and optimisation of the virtualised cloud server

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International Journal of Reliability and Safety 2018年第4期12卷 406-428页

作者： Dang, Weichao Zeng, Jianchao College of Electrical and Information Engineering Lanzhou University of Technology Lanzhou730050 China Division of Industrial and System Engineering Taiyuan University of Science and Technology Taiyuan030024 China School of Computer Science and Control Engineering North University of China Taiyuan030051 China

Software rejuvenation modelling and optimisation of the virtualised cloud server has been studied. A software rejuvenation policy on the virtual machines and the virtual machine monitor has been proposed in order to ensure high availability of the virtualised cloud server. The multi-component system, composed of the virtual machines and the virtual machine monitor, which are structurally dependent, has been reduced to the multiple two-component systems. The state-control-limit-based rejuvenation policy has been proposed and the joint probability density of the degraded state of the two-component VM-VMM has been derived. Furthermore, the solution to the joint probability density has been proposed. Finally, the stationary unavailability of the virtualised cloud server has been modelled. Numerical experiments have verified the correctness of the probability density function and the feasibility of the rejuvenation policy. The state-control-limit-based rejuvenation policy leads to lower unavailability of the virtualised cloud server in comparison with the lifetime-based rejuvenation policy. Copyright © 2018 Inderscience Enterprises Ltd.

关键词： Availability

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