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非高斯随机粗糙表面的数字模拟

系统仿真学报 2009年第10期21卷 2840-2842页

作者：田爱玲孙钊于洵黄梦涛西安工业大学光电工程学院西安710032 西安工业大学电信学院西安710032 西安科技大学电控学院西安710054

针对摩擦学和表面工程领域的研究需求,介绍一种模拟生成非高斯粗糙表面的有效方法。该技术不仅可以生成具有给定标准差、偏斜、峰度和自相关函数的随机粗糙表面,而且还能够控制粗糙表面的相关长度。数字模拟说明了该设计方法的正确性。

关键词：粗糙表面偏斜峰度数字模拟

A novel real-time transient stability prediction method based on post-disturbance voltage trajectories

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A novel real-time transient stability prediction method base...

2011 International Conference on Advanced Power System Automation and Protection(APAP 2011)

作者： ZHAO JinQuan 1* , LI Jun 1 , WU XiaoChen 2 , MEN Kun 2 , HONG Chao 2 & liu YongJun 2 1 School of Energy & Electric Power engineering, Hohai university, Nanjing 210098, china 2 Electric Power Research institute, china South Power Grid Ltd., Guangzhou 510623, china

With the wide application of phasor measurement units （PMU） and wide area measurement system （WAMS） in power system, the real time detection and emergency control of power system transient instability based on the wide-area measurements has brought wide attention. This paper presents a novel technique for predicting transient stability status of a power system following a large disturbance. The synchronously measured samples of the fundamental frequency voltage magnitudes are used to detect the stability. A stability criterion based on the volt-second integration of post-disturbance voltage trajectory is proposed for detecting the transient instability. The drop rate of voltage magnitude after clearing the fault is embed-ded into the proposed criterion since it indicates the severity of disturbance in some extent. There are two integration termination criteria for fast prediction. Compare with traditional transient stability prediction methods, in which the post-fault rotor angle and angular velocity samples are used to produce the instability criteria, the proposed method improves the reliability and rapidity of transient stability detection especially for the multiple swing instability cases. Studies with both IEEE 39 test system and china Sothern Power Grid indicates that the proposed method is effective.

关键词： transient instability prediction, phasor measurement unit post-fault voltage trajectory volt-second integration criterion voltage drop rate

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火灾影响下RC梁的时变可靠性分析

武汉理工大学学报 2009年第8期31卷 58-62页

作者：白丽丽王振清姜封国哈尔滨工程大学航天与建筑工程学院哈尔滨150001 黑龙江科技学院建筑工程学院哈尔滨150027

通过分析火灾发生时RC梁截面内温度场的分布,得出了火灾后RC梁的抗力折减系数,建立了火灾后RC梁的抗力计算模型,同时引入了火灾前抗力和荷载效应随时间而变化的动态可靠性,对长期使用后又遭受火灾作用的RC梁可靠性进行了分析,分析过程... 详细信息

通过分析火灾发生时RC梁截面内温度场的分布,得出了火灾后RC梁的抗力折减系数,建立了火灾后RC梁的抗力计算模型,同时引入了火灾前抗力和荷载效应随时间而变化的动态可靠性,对长期使用后又遭受火灾作用的RC梁可靠性进行了分析,分析过程中考虑了火灾前后两个过程可靠性的相关性。算例分析表明,使用时间和高温作用及两个过程的相关性对梁的可靠性都有一定的影响,在有条件的情况下应给予考虑。

关键词：时变可靠性钢筋混凝土梁火灾相关性

Possibility Theory Based Fault Tree Analysis of Presser Dashing Hand

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Possibility Theory Based Fault Tree Analysis of Presser Dash...

2004安全科学与技术国际会议

作者： TONG Xin1 WANG Ping1 HUANG Hongzhong2 GU Yingkui2 liu Chunsheng3 & WU Weidong3 (1 School of Automation Chongqing university of Posts and Telecommunication Chongqing 400065 china) (2 School of Mechanical engineering Dalian university of technology Dalian 116023 Liaoning china) (3 Department of Mechanical engineering Heilongjiang institute of Science and technology Harbin 150027 Heilongjiang china)

Based on the posbist reliability theory, failure event behavior is characterized in the context of possibility measures and the structure function of a posbist fault tree is defined. Finally, a model

关键词： posbist reliability theory fault tree posbist fault tree analysis presser dashing hand

Report on the Structure Strength and Vibration Mode of Transformer

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Report on the Structure Strength and Vibration Mode of Trans...

2011年亚太青年通信学术会议

作者： Dou CHEN1 Xiangsheng LI2 1Hunan Vocational College of Railway technology Zhuzhou Hunan china 2Central South university of Forestry and technology Logistics institute Changsha Hunan china

To check the reliability of transformer’s strength and vibration mode,we analyze the structure of the transformer,define the Load condition,process the boundary condition and create the finite element *** use ANSYS software to analyze transformer s structure strength and mode,which provides important support to reliable *** the analysis of above,the structure design and the stiffness of transformer is totally meeting with the requirement of design.

关键词： transformer load condition the finite element analysis the structure strength analysis the mode analysis

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8000方挖泥船动力机械远程诊断系统研制

武汉理工大学学报 2010年第13期32卷 118-121页

作者：严新平宗成强盛晨兴尚前明余永华武汉理工大学能源与动力工程学院可靠性工程研究所武汉430063 武汉理工大学船舶动力工程技术交通行业重点实验室武汉430063

针对传统挖泥船动力机械无法实现准确故障诊断的问题,提出了基于无线通讯的远程故障诊断模式,系统由船载子系统、航道局机务管理子系统和实验室诊断中心子系统等组成。通过采集动力机械的相关信息,使用船载子系统对其状态进行初步判别,... 详细信息

针对传统挖泥船动力机械无法实现准确故障诊断的问题,提出了基于无线通讯的远程故障诊断模式,系统由船载子系统、航道局机务管理子系统和实验室诊断中心子系统等组成。通过采集动力机械的相关信息,使用船载子系统对其状态进行初步判别,将可能存在问题的数据通过CDMA网络传输至实验室诊断中心,实现疑难故障的专家会诊,进而指导船员进行相应的操作。系统运行表明:性能稳定,实现了船舶动力设备远程诊断。

关键词：挖泥船远程诊断故障诊断虚拟仪器

Research of Buildings reliability Evaluation Model Base on Fuzzy Neural Network

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Research of Buildings Reliability Evaluation Model Base on F...

2009中国控制与决策会议

作者： Li Lan~1,Zhu Ying-jie~2 Qiu Xue-qin~1,Li Zheng-lei~1 1.College of Computer engineering,Qingdao Technological university,Qingdao 266033,china 2.institute of Civil engineering,Qingdao Technological university,Qingdao 266033,china

＜正＞In this paper,A novel model integrating genetic algorithm and fuzzy neural network was proposed to solve the problem of buildings performance *** reliability assessment is a critical component of any building evaluation system（BES） decision-making *** algorithm was to optimize the connection weights of fuzzy neural network to acquire approximate optimal solution,and fuzzy neural network tuned finely *** results show that more scientific,effective,accurate assessment of building performance can be acquired with ***-based fuzzy neural network model.

关键词： neural network genetic algorithm evaluation model buildings reliability

Investigation of tribological performances of MCMB

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Science china Mathematics 2001年第S1期44卷 177-181页

作者： CUI Xiaohao LI Shenghua SONG Huaihe JIN Yuansheng FU Honglan 1. National tribology Laboratory, Tsinghua university, Beijing 100084, china 2. institute of Carbon Fibers & Composites, Beijing university of Chemical technology, Beijing 100029, china 3. Department of Biology, Peking university, Beijing 100871, china Tsing Hua Univ Natl Tribol Lab Beijing 100084 Peoples R China Beijing Univ Chem Technol Inst Carbon Fibers & Composites Beijing 100029 Peoples R China Peking Univ Dept Biol Beijing 100871 Peoples R China

Tribological properties of Meso-carbon Microbeads (MCMB) powders as a special addi-tive in pentaerythritol were investigated on an Optimal SRV tribotester at 300℃. The coarsely dis-persed lubricant system demonstrates fine lubricious effectiveness at the operation *** friction coefficient dropped from 0.2 to circa 0.12 in the presence of MCMB in pentaerythritolfor the No.45 carbon steel tribomate. Raman spectroscopy analysis indicated the partial transfor-mation of MCMB into increased ordered structures that contributed to the lowering of friction.

关键词： MCMB high temperature lubricate carbon tribology

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改进灰色关联算法在辐射源识别中的应用

通信学报 2010年第S1期31卷 166-171页

作者：林云司锡才周若琳杨慧哈尔滨工程大学信息工程技术研究所黑龙江哈尔滨150001 莱特州立大学

针对复杂电磁环境中电子侦察传感器获得的辐射源信息具有不完整性和模糊性的特点,提出了基于灰色关联和证据理论的辐射源识别新方法。该方法针对一般的主观灰色关联权重可靠性不足的缺点,依据信息熵理论实时计算出灰色关联算法的权重,... 详细信息

针对复杂电磁环境中电子侦察传感器获得的辐射源信息具有不完整性和模糊性的特点,提出了基于灰色关联和证据理论的辐射源识别新方法。该方法针对一般的主观灰色关联权重可靠性不足的缺点,依据信息熵理论实时计算出灰色关联算法的权重,利用自适应熵权灰色关联算法获得证据的基本概率赋值函数。然后再根据证据组合规则和基于基本概率赋值的判决准则,融合不同电子侦察传感器的证据,识别不同类型的辐射源。理论分析和仿真结果表明,与一般的主观灰色关联算法相比,自适应熵权灰色关联算法具有更高的目标识别率、更好的环境适应性和更强的计算可靠性。

关键词：辐射源识别灰色关联算法信息熵理论证据组合规则基本概率赋值函数