检索结果-内蒙古大学图书馆

IEEE Region 10 International Conference TENCON

作者： Norasage Pattanadech Phethai Nimsanong Electrical Engineering Dept King Mongkut's Institute of Technology Ladkrabang Bangkok Thailand Power System Operation and Control Section 2 Metropolitan Electricity Authority Bangkok Thailand

This document proposes the comparison of four statistical classification models for partial discharge (PD) classification as follows: k-nearest neighbors (KNN) model, probabilistic neural network (PNN) model, and other two statistical models using principal component analysis (PCA) for a data reduction approach combined with KNN and PNN models, so called, PCA-KNN model and PCA-PNN model. PD phenomena, corona at high voltage side in air (CHV), corona at low voltage side in air (CLV), surface discharge (SF), and internal discharge (IN) were simulated and measured in the shielding room. Electromagnetic wave due to PD phenomena was detected using a log-periodic antenna and recorded employing a spectrum analyzer. 80 experiments in total were performed for CHV, CLV, SF, and IN. The original independent variables for each classification model, skewness and kurtosis of each period of the captured signals, were calculated. Then, 60% of experimented data was used as a training data for the PD classification model. Another 40% experimented data was used to evaluate the performance of the designed PD classification models. Besides, noise signals were generated with computer program and trained into the PD classification model as well. The peak of noise signal was set up at 10%, 20% and 30% of the peak value of the PD signal. These noise signals were added with the PD signals to generate a mixed noise - PD signal. Then, the mixed noise - PD signals were used to evaluate the performance of the PD classification models. It was found that the designed KNN, PNN, PCA-KNN and PCA - PNN model can predict PD patterns without noise signal with the accuracy 100%. Noise signals with amplitude of 20% or more of peak value of PD signal have obviously influence the accuracy of PD pattern classification. The combination of PCA with KNN model can improve the ability of PD classification compared with KNN PD classification model. However, it seems that PCA provided negative effect when PCA was c

关键词： Partial discharges Noise Principal component analysis Discharges (electric) Atmospheric modeling Data models Training

来源：评论

学校读者我要写书评

暂无评论

A formal model for attack mutation using dynamic description logics 8

A formal model for attack mutation using dynamic description...

引用

8th IFIP International Conference on Intelligent Information Processing, IIP 2014

作者： Wang, Zhuxiao Guo, Jing Shi, Jin He, Hui Zhang, Ying Peng, Hui Tian, Guanhua School of Control and Computer Engineering State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power University Beijing102206 China National Computer Network Emergency Response Technical Team/Coordination Center of China Beijing100029 China Education Technology Center Beijing International Studies University Beijing100024 China Institute of Automation Chinese Academy of Sciences Beijing100190 China

ISBN: (纸本)9783662449790

All currently available Network-based Intrusion Detection systems (NIDS) rely upon passive protocol analysis which is fundamentally flawed as an attack can evade detection by exploiting ambiguities in the traffic stream as seen by the NIDS. We observe that different attack variations can be derived from the original attack using simple transformations. This paper proposes a semantic model for attack mutation based on dynamic description logics (DDL(X)), extensions of description logics (DLs) with a dynamic dimension, and explores the possibility of using DDL(X) as a basis for evasion composition. The attack mutation model describes all the possible transformations and how they can be applied to the original attack to generate a large number of attack variations. Furthermore, this paper presents a heuristics planning algorithm for the automation of evasion composition at the functional level based on DDL(X). Our approach employs classical DL-TBoxes to capture the constraints of the domain, DL-ABoxes to present the attack, and DL-formulas to encode the objective sequence of packets respectively. In such a way, the evasion composition problem is solved by a decidable tableau procedure. The preliminary results certify the potential of the approach. © IFIP International Federation for Information Processing 2014.

关键词： Semantics

来源：评论

学校读者我要写书评

暂无评论

A molecular cryptography model based on structures of DNA self-assembly

引用

Chinese Science Bulletin 2014年第11期59卷 1192-1198页

作者： Yang, Jing Ma, Jingjing Liu, Shi Zhang, Cheng Beijing Key Laboratory of New Technology and System on Measuring and Control for Industrial Process School of Control and Computer Engineering North China Electric Power University Beijing China Key Laboratory of High Confidence Software Technologies Ministry of Education Institute of Software School of Electronics Engineering and Computer Science Peking University Beijing China

With the progress of DNA computing, DNA-based cryptography becomes an emerging interdisciplinary research field. In this paper, we present a novel DNA cryptography that takes advantage of DNA self-assembled structure. Making use of the toehold strands recognition and strand displacement, the bit-wise exclusive-or (XOR) operation is carried out to fulfill the information encryption and decryption in the form of a one-time-pad. The security of this system mainly comes from the physical isolation and specificity of DNA molecules. The system is constructed by using complex DNA self-assembly, in which technique of fluorescent detection is utilized to implement the signal processing. In the proposed DNA cryptography, the XOR operation at each bit is carried out individually, thus the encryption and decryption process could be conducted in a massive, parallel way. This work may demonstrate that DNA cryptography has the great potential applications in the field of information security.

关键词：

来源：评论

学校读者我要写书评

暂无评论

A short-term heuristic method for peak operation of pumped hydroenergy storage plants between multiple power grids on bulk power grid platform

引用

Dianli Xitong Zidonghua/Automation of Electric power systems 2014年第9期38卷 53-60页

作者： Cheng, Xiong Shen, Jianjian Cheng, Chuntian Wu, Xinyu Lu, Jianyu Li, Gang Institute of Hydropower System and Hydroinformatics Dalian University of Technology Dalian116024 China School of Control Science and Engineering Dalian University of Technology Dalian116024 China East China Electric Power Dispatching and Controlling Subcenter State Grid Corporation of China Shanghai200120 China

A short-term heuristic method of pumped (hydroenergy) storage plants (PSP) operation for regulating peak loads of multiple power grids has been developed based on the actual project of East China Grid (ECG). The power generation or pump power of PSP is decided by the maximum or minimum value of the total load at each iteration. And power generation or pump power is further allocated between power grids using two strategies, known as power cutup and combination optimization. This process is repeated till the desired target objectives of PSP are satisfied. The case results over ECG show that the proposed method is able to solve the load distribution problem of PSP between multiple power grids. ©2014 State Grid Electric power Research institute Press.

关键词： Heuristic methods

来源：评论

学校读者我要写书评

暂无评论

Modeling and detection of rotating stall in axial flow compressors, II: Experimental study for a low-speed compressor in Beihang University

引用

Kongzhi Lilun Yu Yingyong/control Theory and Applications 2014年第10期31卷 1414-1422页

作者： Wang, Cong Si, Wen-Jie Wen, Bin-He Zhang, Ming-Ming Wang, Yong Hou, An-Ping College of Automation Science and Technology South China University of Technology GuangzhouGuangdong510640 China Institute of AVIC Aviation Motor Control System WuxiJiangsu214063 China Department of Mechanics and Engineering Science Peking University Beijing100871 China School of Energy and Power Engineering BeiHang University Beijing100191 China

Early detection of rotating stall and surge in axial flow compressors is of great importance for improving the working efficiency and stability of the compressor. Based on deterministic learning (DL) theory and dynamical pattern recognition, this paper presents experimental research for approximately accurate modeling and rapid detection of stall precursors, and then employs a low-speed axial flow compressor test rig of Beihang University for online experimental verification. Firstly, by installing high response dynamic pressure transducers arranged circumferentially around the casing of the axial compressor, the dynamic pressure data are collected. Based on deterministic learning theory, the system dynamics underlying prestall and stall inception patterns are identified. Secondly, based on modeling results, rapid detection of small oscillation faults is used to perform the detection of stall precursors. Sufficient online experiments are conducted to investigate the efficiency of the approach. Results show that, in different working speeds, this approach successfully detects inception signal of aerodynamic instability of the compressor 0:3 s~1 s in advance to the start of rotating stalls. ©, 2014, South China University of Technology. All right reserved.

关键词： Pattern recognition

来源：评论

学校读者我要写书评

暂无评论

The uncertainty and its influence of wind generated power on power system transient stability under different penetration

The uncertainty and its influence of wind generated power on...

引用

International Conference on power system Technology (powerCON)

作者： Dong Han Jin Ma Ancheng Xue Tao Lin Guoqiang Zhang Institute of Electrical Engineering Chinese Academy of Sciences Beijing China School of Electrical and Information Technology University of Sydney Australia Key Laboratory of Power System Protection and Dynamic Security Monitoring and Control of Ministry of Education China Electric Power University Beijing China

Wind gust has the characteristics of sudden and brief increase in wind speed. Moreover, if the penetration of wind power is high, its inherent characteristics may impacts on power system stability. In order to analyze the impacts of wind gust and wind penetration on wind turbine generator further the system stability, three signals to stand for wind gust types are adopted in this paper, i.e. lope signal, 1-consine discrete signal and step signal. This paper analyzes quantitatively the uncertainties of wind generated power arising from wind speed using different wind models. Then, two-area four-machine system is modified in MATLAB, where the double-fed induction wind generators are used to simulate different wind power penetration. It is shown that different types of wind models and variations wind speed have different impacts on the generated wind power of wind farm. Moreover, it can be inferred when the penetration of wind power is high, the generated wind power outputs affect power system stability largely.

关键词： Wind power generation Wind speed power system stability Wind farms Uncertainty Stability analysis Generators

来源：评论

学校读者我要写书评

暂无评论

Uncertainty analysis of load model based on the sparse grid stochastic collocation method

Uncertainty analysis of load model based on the sparse grid ...

引用

IEEE PES Transmission and Distribution Conference and Exposition

作者： Dong Han Tao Lin Yilu Liu Jin Ma Guoqiang Zhang Institute of Electrical Engineering Chinese Academy of Sciences 100190 Beijing China University of Tennessee at Knoxville 37996 Knoxville TN USA Key Laboratory of Power System Protection and Dynamic Security Monitoring and Control of Ministry of Education North China Electric Power University 102206 Beijing China

There are a lot of uncertainties in load modeling and it parameter solutions, which is difficult to estimate uncertainty with traditional methods if the number of parameters is immense. This paper adopts the sparse grid stochastic collocation method for uncertainty analysis, and proposes a strategy available to calculate the multi-parameter uncertainty arising from load models. For multiple random inputs, sparse grid method can be regarded as an extension of Gaussian quadrature formulas in multi-dimensional cases. Based on the sparse grid stochastic collocation method, the collocation points can be selected among the Gaussian points of (l+1) order and lower than (l+1) order. Compared to other probabilistic analysis methods, it can not only maintain the integral precision but avoid the exponential rise of collocation points, and can greatly reduce simulation time. The case study on multiparameter uncertainty of the composite load model verifies the integral precision and the validity of the proposed method.

关键词： Uncertainty Load modeling Stochastic processes Computational modeling power systems Polynomials Analytical models

来源：评论

学校读者我要写书评

暂无评论

Economic Analysis of Vacuum Transfer Tube for Conveying Working Medium of CSP

引用

Energy Procedia 2014年 49卷 1664-1672页

作者： M.J. Bai Y.N. Niu E.S. Xu Y. Xu Hubei Salnner Vacuum Science & Technology Co. Ltd Huanggang Huibei438000China Key Laboratory of Condition Monitoring and Control for Power Plant Equipment North China Electric Power University Changping District Beijing102206 China Key Laboratory of Solar Thermal Energy and Photovoltaic System Institute of Electrical Engineering Chinese Academy of Science Haidian Dis trict Beijing100190 China

Parabolic trough solar thermal power generation system has long distance transfer pipes for the heat transfer fluid (HTF), causing large heat losses, and which requires a lot of energy for thermal protection. To improve piping insulation effect and reduce the heat losses, Hubei Salnner Vacuum Science & Technology Co., Ltd has designed and developed a suitable vacuum transfer tube for the HTF of solar thermal power generation system, which can reduce heat losses effectively. Taking the vacuum transfer tube as the object, this paper established the heat loss model of the vacuum transfer tube, and also proposed the model of the time sample under the unit's operating conditions according to the actual weather conditions in typical years of a 50MW parabolic trough solar thermal power plant construction site. On above basis, according to the structure of the power plant system and the operating conditions, this paper took intensive research on the cost and economy of the parabolic trough solar thermal power generation system which uses the vacuum transfer tube, and the results showed that vacuum transfer tube for convering working medium of CSP has good economical benefits.

关键词： Vacuum transfer tube 50MW parabolic trough solar thermal power plant Heat loss model Economical benefit

来源：评论

学校读者我要写书评

暂无评论

Modeling and detection of rotating stall in axial flow compressors: Part I - investigation on high-order M-G models via deterministic learning

引用

Zidonghua Xuebao/Acta Automatica Sinica 2014年第7期40卷 1265-1277页

作者： Wang, Cong Wen, Bin-He Si, Wen-Jie Peng, Tao Yuan, Cheng-Zhi Chen, Tian-Rui Lin, Wen-Yu Wang, Yong Hou, An-Ping College of Automation Science and Engineering South China University of Technology Guangzhou 510640 China AVIC Aviation Motor Control System Institute Wuxi 214063 China College of Electronic Information and Automation Chongqing University of Technology Chongqing 400054 China School of Automation Guangdong University of Technology Guangzhou 510006 China Department of Mechanics and Engineering Science Peking University Beijing 100871 China School of Energy and Power Engineering Beihang University Beijing 100191 China

Rotating stall and surge are important and challenging problems in the area of axial compressors. This paper presents an approach for approximately accurate modeling and rapid detection of stall precursors based on deterministic learning. Firstly, based on the high-order compressor model (Mansoux model), a method for modeling the system dynamics corresponding to stall precursors is presented by employing deterministic learning algorithm;Secondly, a scheme for rapid detection of stall precursors is proposed by using dynamical pattern recognition algorithm;Thirdly, experiments are conducted on a low-speed research compressor of Beihang University. By measuring relevant parameters of the compressor, the Mansoux-Beihang model is obtained. Simulation studies on the Mansoux-C2 model and the Mansoux-Beihang model are included to show the effectiveness of the approach. Copyright © 2014 Acta Automatica Sinica. All rights reserved.

关键词： Fault detection

来源：评论

学校读者我要写书评

暂无评论

Design and implementation of a non-contact magnetic field measurement based fault location system for overhead transmission line

Design and implementation of a non-contact magnetic field me...

引用

2013 IEEE International Conference on Smart Instrumentation, Measurement and Applications, ICSIMA 2013

作者： Huang, Qi Yao, Ruoting Li, Fuchao Zhen, Wei Sichuan Provincial Key Lab of Power System Wide-area Measurement and Control School of Energy Science and Engineering UESTC Chengdu China Sichuan Electric Power Research Institute Chengdu China

ISBN: (纸本)9781479908431

As the rapid development MEMS (micro-electromechanical systems) packaging technology and magnetoresistance material technology, MR (magnetoresistive) sensors based on magnetoresistance effect which can carry out point measurement of magnetic field may change the measurement techniques in power systems. The currently available fault location of overhead transmission line approaches are mainly based on traveling-wave technique and impedance-based measurement technique. The novel approach based on non-contact measurement of magnetic field is advantageous over traditional approaches in that it is independent of the distributed line parameters and has a location error smaller than one span. In this paper, after a brief reviewing of the whole system architecture, design of a sensor prototype and the associated monitoring software are presented, and tests are performed to verify the functionalities of the designed system. The sensor is developed based on a 3-D AMR (anisotropic magnetoresistance) sensor and the software supports GIS interface, making the fault location intuitively clear and convenient. © 2013 IEEE.

关键词： Location

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：