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关于电力通信传输网设计的分析 被引量:1
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作者 郑建新 《科技与生活》 2012年第24期-,共2页
随着科技的不断发展,电力通信的传输网设计越来越引起人们的重视.并且对电力通信的传输网进行设计对现实生活意义重大.这篇文章对电力通信的传输网设计做了详细的介绍.
关键词 电力通信 传输网设计 分析
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DWT BASED HMM FOR FACE RECOGNITION 被引量:1
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作者 Shen Linlin Ji Zhen +1 位作者 Bai Li Xu Chen 《Journal of Electronics(China)》 2007年第6期835-837,共3页
A novel Discrete Wavelet Transform (DWT) based Hidden Markov Module (HMM) for face recognition is presented in this letter. To improve the accuracy of HMM based face recognition algorithm, DWT is used to replace Discr... A novel Discrete Wavelet Transform (DWT) based Hidden Markov Module (HMM) for face recognition is presented in this letter. To improve the accuracy of HMM based face recognition algorithm, DWT is used to replace Discrete Cosine Transform (DCT) for observation sequence ex- traction. Extensive experiments are conducted on two public databases and the results show that the proposed method can improve the accuracy significantly, especially when the face database is large and only few training images are available. 展开更多
关键词 Discrete Wavelet Transform (DWT) Hidden Markov Model (HMM) Face recognition
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Smart Grid Wide-Area Transmission System Visualization 被引量:3
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作者 Thomas J.Overbye James Weber 《Engineering》 SCIE EI 2015年第4期466-474,共9页
The installation of vast quantities of additional new sensing and communication equipment, in conjunction with building the computing infrastructure to store and manage data gathered by this equipment, has been the fi... The installation of vast quantities of additional new sensing and communication equipment, in conjunction with building the computing infrastructure to store and manage data gathered by this equipment, has been the fi rst step in the creation of what is generically referred to as the "smart grid" for the electric transmission system. With this enormous capital investment in equipment having been made, attention is now focused on developing methods to analyze and visualize this large data set. The most direct use of this large set of new data will be in data visualization. This paper presents a survey of some visualization techniques that have been deployed by the electric power industry for visualizing data over the past several years. These techniques include pie charts, animation, contouring, time-varying graphs, geographic-based displays, image blending, and data aggregation techniques. The paper then emphasizes a newer concept of using word-sized graphics called sparklines as an extremely eff ective method of showing large amounts of timevarying data. 展开更多
关键词 electric power systems wide-area visualization power flow transient stability smart grid sparklines
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A Nodal Electricity Market Design Based on Regulated Access to Transmission Network
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作者 Jean Constantinescu 《Journal of Energy and Power Engineering》 2013年第12期2404-2408,共5页
Accomodation of power system constraints with the market mechanism is encountered as a major challenge along the way toward implementation of different electricity market designs. Allocation of fixe or flow-dependent ... Accomodation of power system constraints with the market mechanism is encountered as a major challenge along the way toward implementation of different electricity market designs. Allocation of fixe or flow-dependent inter-zone trading capacities by the PX (power exchange) can not be accepted unreservedly. The paper is meant to show that a nodal electricity market design that is based on bids for local energy and a regulated transmission access including allocation of "entry-exit" transmission capacity would be the desired solution. The market players could easily optimize their portfolio while the TSOs (transmission system operators) are requested to mobilize the network's in-built flexibility to increase the cross zonal capacity. In the proposed market design, the PX's allocation of trading capacity is clearly separate from the TSO's management of the power system operational constraint5. Clear operator roles would enlarge access to electricity market as well as market integration of variable RESs (renewable energy sources) that are critically dependent on short notice access to regionat markets, 展开更多
关键词 Electricity market design nodal model network access transmission capacity congestion management.
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Power-line Modem over the Low Voltage Grid Using Direct Sequence Spread Spectrum Techniques
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作者 A. Mahgoub H. Abdeel-Baky E. El-Badawy 《Journal of Energy and Power Engineering》 2011年第6期562-568,共7页
Power-line networks are designed to deliver electricity. They reach most of the domiciles and other buildings nowadays, so most of the people have access to it. On the other hand the backbone for the communications ne... Power-line networks are designed to deliver electricity. They reach most of the domiciles and other buildings nowadays, so most of the people have access to it. On the other hand the backbone for the communications networks is not available in all countries especially the developing ones. A high cost and changing the design for the networks may be needed to construct this backbone. If data can be transmitted over the power-line networks, a recognized cost and time save can be achieved. In Egypt, the infrastructure is not always available for constructing a communications network backbone due to the already designed buildings before the need for these backbones. In this paper, we overcome this problem by designing a reliable Power-line Modem that operates safely on the low voltage grid. The modem is based on the Direct Sequence Spread Spectrum technique. It uses the mains zero crossing as an efficient way for the synchronization between the transmitter and the receiver. The Modem takes into account the problems of the Power-line including noise, attenuation and impedance dismatching. 展开更多
关键词 Power-line modem DS/SS micro-controller (firmware) low voltage grid.
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