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2010 3rd IEEE International Conference on Computer Science and information Technology—ICCSIT 2010

作者： Cui Haoyang school of Computer Science and information engineering shanghai university of Electric Power shanghai china school of communication and information engineering shanghai university shanghai china Hangzhou Qianjiang River Electic Group Co. Ltd.Hangzhou china Tang Zhong school of Computer Science and information engineering shanghai university of Electric Power shanghai china Fang Yong school of communication and information engineering shanghai university shanghai china Liu Jun Hangzhou Qianjiang River Electic Group Co. Ltd.Hangzhou china Ye Bo school of Computer Science and information engineering shanghai university of Electric Power shanghai china

This paper presents a fault diagnosis method for power *** diagnosis plays an importance role in the efforts for transformer diagnosis to shift form "preventive maintenance"to"condition based maintenance"（CBM）,and consequently to reduce the maintenance *** since its birth,numerous techniques have been researched in this field,each method however,has its own advantages and *** diagnosis is a challenging problem because there are numerous fault situations that can possibly happen to a electrical *** is one of the most importance parameters for the diagnosis of electrical transformers fault *** on the appearance information of temperature,a fault monitoring system can make diagnosis intelligently,therefore it can provide a rapid scientific treatment options for the field *** the problem of transformer fault diagnosis based on temperature information,we use Bayesian probability density theory method to explain the equipment fault diagnosis *** maximum membership probability principle will be adapted to judge whether the equipment is *** results shows that when the working temperature is between 64～72 oC,the diagnosis results without compensation is working on normal state,while the diagnosis results with compensation is general fault ***,the diagnosis results without compensation have large error with the actual *** proposed methodology in this paper was testified having important significance in improving the reliability and the information level of transformer operation.

关键词： transformers Bayesian probability density theory fault diagnosis

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多信道IM-DD密集波分复用光纤传输系统中的交叉相位调制效应

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通信学报 2001年第8期22卷 47-53页

作者：朱栩林如俭上海交通大学宽带光网络研究中心上海200030 上海大学通信学院上海201800

本文研究了交叉相位凋制（ＸＰＭ）对ＤＷＤＭ数字基带主干传输网性能的影响，建立了表征ＸＰＭ效应对任意调制信号在色散信道中传输的指标损伤的等效系统函数模型，并据此推导出了不同系统参数条件下（基带信号速率、波长信道间隔、复... 详细信息

本文研究了交叉相位凋制（ＸＰＭ）对ＤＷＤＭ数字基带主干传输网性能的影响，建立了表征ＸＰＭ效应对任意调制信号在色散信道中传输的指标损伤的等效系统函数模型，并据此推导出了不同系统参数条件下（基带信号速率、波长信道间隔、复用信道数）计算ＸＰＭ导致和系统光功率代价的计算公式。通过数值模拟计算证明了在基带信号速率高（＞２．５Ｇｂｉｔ／ｓ）、波长信道间隔窄（～１ｎｍ）、复用信道数多（＞８）的条件下ＸＰＭ效应将成为限制系统性能的主要非线性因素。

关键词：交叉相位调制密集波分复用系统 IM-DD 光纤传播系统

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基于多相滤波的直接数字正交变换技术

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上海大学学报（自然科学版） 2003年第1期9卷 9-12,54页

作者：颜彪许宗泽邹国良南京航空航天大学电子工程系南京210016 上海大学通信与信息工程学院上海200072

为了尽可能多地用软件来实现通信和雷达接收机的处理功能,需要直接对中频信号进行采样,然后通过数字正交变换的方法得到同相和正交分量.该文首先对多相滤波法实现数字正交变换的原理进行了分析,然后根据多抽样率信号处理理论详细证明了... 详细信息

为了尽可能多地用软件来实现通信和雷达接收机的处理功能,需要直接对中频信号进行采样,然后通过数字正交变换的方法得到同相和正交分量.该文首先对多相滤波法实现数字正交变换的原理进行了分析,然后根据多抽样率信号处理理论详细证明了内插时延滤波器能够用多相滤波器组中的子滤波器实现.最后,计算机仿真结果表明,所设计的内插时延滤波器的相频特性和幅频特性均满足要求.

关键词：中频采样数字正交变换多相滤波器组软件无线电 A/D变换信号处理计算机仿真

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Extracting Moving Objects Based on Morphological Motion Filter

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Journal of shanghai university(English Edition) 2001年第1期5卷 53-56页

作者： SHI Li, ZHANG Zhao yang school of communication and information engineering, shanghai university, shanghai 200072, china school of communication and information engineering Shanghai University Shanghai China

This paper presents a new approach to the extraction of a moving object from video sequence. The method is based on morphological motion filter using connected operator and a proposed new filtering criterion. The morphological motion filter aims to detect motion which is distinct from that of the background, and thereby locates independently moving physical objects in the scenes. Experiments show that the algorithm can extract object from moving backgrounds efficiently.

关键词： Mpeg 4 morphological motion filter connected operator motion estimation

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Wavelength Channel Bandwidth of Wavelength-Selective Devices

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Journal of shanghai university(English Edition) 2001年第1期5卷 48-52页

作者： XIAO Yan ping, WU Ya ming school of communication and information engineering, shanghai university, shanghai 200072, china school of communication and information engineering Shanghai University Shanghai China

Narrow bandwidth is a crucial factor in a high performance wavelength selective device(WSD). There are many different expressions to estimate bandwidths of many different WSDs. In this paper, we derive an important rule that the differential time delay between two coupling modes is the most important factor deciding the wavelength channel bandwidth for several different WSDs. This rule reveals that larger differential time delay between two coupling modes results in higher discrimination level of the operating wavelength. Based on the rule, a novel design of wavelength selective coupler that has a bandwidth narrower than normal couplers is presented.

关键词： wavelength channel bandwidth wavelength selective device(WSD) differential time delay

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A Fast Fractal Image Compression Coding Method

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Journal of shanghai university(English Edition) 2001年第1期5卷 57-59页

作者： XU Chang man 1, ZHANG Zhao yang school of communication and information engineering, shanghai university, shanghai 200072, china school of communication and information engineering Shanghai University Shanghai China

Fast algorithms for reducing encoding complexity of fractal image coding have recently been an important research topic. Search of the best matched domain block is the most computation intensive part of the fractal encoding process. In this paper, a fast fractal approximation coding scheme implemented on a personal computer based on matching in range block's neighbours is *** results show that the proposed algorithm is very simple in implementation, fast in encoding time and high in compression ratio while PSNR is almost the same as compared with Barnsley's fractal block coding .

关键词： neighbour fractal block coding range block,domain block iterated function system

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A New Shape-Coding Algorithm by Using Wavelet Transform

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Journal of Systems engineering and Electronics 2003年第2期14卷 69-73页

作者： Shi Xuli & Zhang Zhaoyang communication school, shanghai university, shanghai 200072, P. R. china communication school Shanghai University Shanghai 200072 P. R. China

In this paper, we propose a new shape-coding algorithm called wavelet-based shape coding (WBSC). Performing wavelet transform on the orientation of original planar curve gives the corners called corner-1 points and end of arcs that belong to the original curve. Each arc is represented by a broken line and the corners called corner-2 points of the broken line are extracted. A polygonal approximation of a contour is an ordered list of corner-1 points, ends of arcs and corner-2 points which are extracted by using the above algorithm. All of the points are called polygonal vertices which will be compressed by our adaptive arithmetic encoding. Experimental results show that our method reduces code bits by about 26% compared with the context-based arithmetic encoding (CAE) of MPEG-4, and the subjective quality of the reconstructed shape is better than that of CAE at the same Dn.

关键词： Wavelet transform Shape coding WBSC MPEG-4 CAE.

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Modeling of human colonic blood flow for a novel artificial anal sphincter system

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Journal of Zhejiang university-Science B(Biomedicine & Biotechnology) 2008年第9期9卷 734-738页

作者： Peng ZAN, Guo-zheng YAN, Hua LIU (school of Electronics, information and Electrical engineering, shanghai Jiao Tong university, shanghai 200240, china) school of Electronics Information and Electrical Engineering Shanghai Jiao Tong University Shanghai 200240 China. zanpeng@***

A novel artificial anal sphincter system has been developed to simulate the normal physiology of the human anorectum. With the goal of engineering a safe and reliable device, the model of human colonic blood flow has been built and the relationship between the colonic blood flow rate and the operating occlusion pressure of the anorectum is achieved. The tissue ischemia is analyzed based on constitutive relations for human anorectum. The results suggest that at the planned operating occlusion pressure of less than 4 kPa the artificial anal sphincter should not risk the vascularity of the human colon.

关键词： Incontinence Artificial anal sphincter Colonic blood flow Tissue ischemia

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The Absorption Characteristics of Inhomogeneous Double-Clad Fibers

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光学学报 2003年第S1期23卷 70-71页

作者： Hui Zhang Zihua Wang Zhongyin Xiao (school of communication and information engineering, shanghai university, shanghai, 200072, P.R.china school of communication and information engineering Shanghai University Shanghai 200072 P.R.China

The absorption characteristics of radially inhomogeneous double-clad fiber (DCF) are investigated firstly with the method of caustic radius, combined with the method of WKBJ. The results are significant for double-cla... 详细信息

关键词： of et In as The Absorption Characteristics of Inhomogeneous Double-Clad Fibers mode DCF for into

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Hurst Exponent Analysis of Financial Time Series

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Journal of shanghai university(English Edition) 2001年第4期5卷 269-272页

作者： SANG Hong wei, MA Tian, WANG Shuo zhong school of communication and information engineering, shanghai university, shanghai 200072, china school of communication and information engineering Shanghai University Shanghai China

Statistical properties of stock market time series and the implication of their Hurst exponents are discussed. Hurst exponents of DJIA (Dow Jones Industrial Average) components are tested using re scaled range analysis. In addition to the original stock return series, the linear prediction errors of the daily returns are also tested. Numerical results show that the Hurst exponent analysis can provide some information about the statistical properties of the financial time series.

关键词： Hurst exponent linear prediction error financial time series

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