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基于Bayes定理和μGA的结构损伤识别方法研究

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计算机科学 2011年第B10期38卷 408-411页

作者：钱小妹严刚电子科技大学空天科学技术研究院成都611731 南京航空航天大学飞行器结构力学与控制教育部重点实验室南京210016

提出了一种基于Bayes定理和μGA(微种群遗传算法)的方法,用于识别结构中损伤的位置和程度等参数并分析其不确定性。该方法在获得测量信息后,结合损伤模型,根据Bayes定理更新获得损伤模型参数的后验概率密度函数,以实现在不确定性情况下... 详细信息

提出了一种基于Bayes定理和μGA(微种群遗传算法)的方法,用于识别结构中损伤的位置和程度等参数并分析其不确定性。该方法在获得测量信息后,结合损伤模型,根据Bayes定理更新获得损伤模型参数的后验概率密度函数,以实现在不确定性情况下对损伤的识别。为最大化损伤模型参数的后验概率密度函数,采用μGA搜索获得描述损伤的全局最优参数。将该方法应用于板结构损伤识别,并进行了数值仿真研究以验证所提方法的有效性。

关键词： Bayes定理微种群遗传算法损伤识别不确定性

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微腔激光器数码调制及其光纤传输的研究

中国激光 1998年第9期25卷 833-836页

作者：赵红东林世鸣张存善王守武沈光地北京工业大学电子工程学系河北工业大学应用数理系中国科学院半导体所集成光电子学国家重点实验室

从微腔半导体激光器速率方程出发，分析讨论了微腔激光器的脉码调制特性，发现微腔具有较规则的脉冲响应，可以减少误码率；自发发射因子为０．１的微腔，具有脉码率高达５０Ｇｂｉｔ／ｓ良好的调制眼图，微腔激光器在光互联中将有广泛... 详细信息

从微腔半导体激光器速率方程出发，分析讨论了微腔激光器的脉码调制特性，发现微腔具有较规则的脉冲响应，可以减少误码率；自发发射因子为０．１的微腔，具有脉码率高达５０Ｇｂｉｔ／ｓ良好的调制眼图，微腔激光器在光互联中将有广泛的应用前景。模拟了以微腔激光器为光源的光纤通信系统，给出脉码率为１０Ｇｂｉｔ／ｓ传输不同距离的接收眼图，证明能够实现６０ｋｍ的传输。

关键词：半导体微腔光纤传输接收眼图半导体激光器

RELIABILITY MODELS OF A BRIDGE SYSTEM STRUCTURE UNDER INCOMPLETE INFORMATION

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RELIABILITY MODELS OF A BRIDGE SYSTEM STRUCTURE UNDER INCOMP...

Mixed uncertainty analysis of polycyclic aromatic hydrocarbon inhalation and risk assessment in ambient air of Beijing

第四届质量与可靠性国际会议

作者： YUE SONG Department of applied mathematics Xidian University Xi’an ShanXi {2. 710071 SAN-YANG LIU HAI-LIN FENG Department of applied mathematics Xidian University Xi’an ShanXi {2. 710071

＜正＞ Most methods of system reliability analysis assume that the precise probability distributions of the component time to failure are available and the system components are independent. However this assumption may be unreasonable in a wide scope of cases. Therefore imprecise reliability modes of a bridge system structure are put forward in this paper when the above assumptions are violated, the analysis is based on only some partial information about the component lifetime distributions. The effect of the component independence condition on the reliability of systems is studied.

关键词： reliability bridge system structure imprecise probability theory.

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Journal of Environmental sciences 2008年第4期20卷 505-512页

作者： College of Environmental sciences and Engineering, Peking University, Beijing 100871, china GUO Huaicheng LIU Yong HUANG Kai WANG Zhen ZHAN Xinye 不详 School of Natural Resources and Environment University of Michigan Ann Arbor 48109 USA Department of Civil and Resource Engineering Dalhousie University Halifax NS B3JIZ1 Canada

This article presents the application of an integrated method that estimates the dispersion of polycyclic aromatic hydrocarbons （PAHs） in air, and assesses the human health risk associated with PAHs inhalation. An uncertainty analysis method consisting of three components were applied in this study, where the three components include a bootstrapping method for analyzing the whole process associated uncertainty, an inhalation rate （IR） representation for evaluating the total PAH inhalation risk for human health, and a normally distributed absorption fraction （AF） ranging from 0% to 100% to represent the absorption capability of PAHs in human body. Using this method, an integrated process was employed to assess the health risk of the residents in Beijing, china, from inhaling PAHs in the air. The results indicate that the ambient air PAHs in Beijing is an important contributor to human health impairment, although over 68% of residents seem to be safe from daily PAH carcinogenic inhalation. In general, the accumulated daily inhalation amount is relatively higher for male and children at 10 years old of age than for female and children at 6 years old. In 1997, about 1.73% cancer sufferers in Beijing were more or less related to ambient air PAHs inhalation. At 95% confidence interval, approximately 2.2.309 individual cancer incidences can be attributed to PAHs pollution in the air. The {2. of greater than 500 cancer occurrence is 15.3%. While the inhalation of ambient air PAHs was shown to be an important factor responsible for higher cancer occurrence in Beijing, while the contribution might not be the most significant one.

关键词： polycyclic aromatic hydrocarbons (PAHs) uncertainty analysis human health risk

Extreme parameter sensitivity of transient persistence in spatially coupled ecological systems

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Theoretical & applied Mechanics Letters 2011年第6期1卷 51-56页

作者： Lin Du, Wei Xu,) and Zhanguo Li Department of applied mathematics, Northwestern Polytechnical University, Xi’an 710072.{2. Department of applied mathematics Northwestern Polytechnical University Xi'an 710072 China

This paper investigates persistence of transient dynamics depending on parameters in spatially coupled ecological systems. We emphasis that the persistence time can be obtained by populations of species or Lyapunov exponents of transient dynamics. It is found that extreme sensitive dependence of persistence on parameters occurs commonly in ecological models. A non-zero uncertainty exponent is used to characterize the high sensitivity in a reasonable parameter region. The result of a small uncertainty exponent indicates a fractal structure of transient persistence in the two-dimensional parameter space. In spite of different methods of measurement, the fractal dimensions have a good consistency. Since populations of natural communities with many coupled oscillators are often affected by disturbance of migration rates, the large probability of error in estimating persistence of transients should be concerned.

关键词： transient dynamics predator-prey systems persistence sensitivity uncertainty exponents fractal dimensions

Some Reliability Problems Arising in the M^x/G(M/G)/1 Repairable Queueing System with Single Delay Vacation

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Journal of Systems Science and Systems Engineering 2001年第3期13卷 306-314页

作者： TANG Ying-hui Department of applied Math., University of Electronics Science & Technology of china, Chengdu 610054, china Department of applied Math. University of Electronics Science & Technology of China Chengdu 610054 China

On the basis of Ref.\, the M x/G(M/G)/1 repairable queueing system with single delay vacation is discussed again. The following reliability problems of the service station are studied: (a) The probability that it fails at time t , i.e. its unavailability; (b) The expected failure number during the time interval (0,t\];; (c) The expected failure number during the ″server busy period″; (d) The expected downtime during the time interval (0,t\]. Some reliability results of the service station are obtained. These results would be interest to reliability analysts.

关键词： repairable vacation service station unavailability failure number downtime

ON THE COMMUTABILITY OF ESSENTIAL INFIMUM AND CONDITIONAL EXPECTATION OPERATIONS

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chinese Science Bulletin 1985年第8期30卷 1013-1018页

作者：严加安 institute of applied {2. Academia Sinica Beijing

Ⅰ. MAIN RESULT Let (Ω,P) be a probability space, and H a nonempty family of random variables. We denote by ess. inf H or ess. inf ξ∈ H the essential infimum of H, which always exists. In this note we only deal wit... 详细信息

关键词： nonempty trivial integrable satisfied proof generalize nonnegative probability Riesz filtered

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求解作业车间调度问题的改进自适应遗传算法

系统工程理论与实践 2004年第2期24卷 58-62页

作者：王万良吴启迪宋毅浙江工业大学信息工程学院浙江杭州310014 同济大学电子与信息工程学院上海200092

　根据当前代种群中的最优个体应该保留,但也要一定交叉与变异概率的思想,提出了改进的自适应遗传算法,开发了工程应用软件包,应用于求解作业车间调度问题,显著提高了收敛速度.特别是在搜索过程中系统能够自动给定交叉概率和变异概率,... 详细信息

　根据当前代种群中的最优个体应该保留,但也要一定交叉与变异概率的思想,提出了改进的自适应遗传算法,开发了工程应用软件包,应用于求解作业车间调度问题,显著提高了收敛速度.特别是在搜索过程中系统能够自动给定交叉概率和变异概率,符合工程实际需要.

关键词：生产调度作业车间调度遗传算法自适应组合优化

A　Genetic　Algorithm　for　Estimations　of　Parameters　under　Partial　Order　Restrictions

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Systems Science and Systems Engineering 1997年第3期7卷 107-115页

作者： ZHAO Ruiqing College of Mechanical Engineering, Shijiazhuang 050003 LIU Baoding Department of applied mathematics, Tsinghua University, Beijing 100084

The parameters of probability distributions under partial order restrictions are usually estimated by maximum likelihood estimates(MLE) and formulated as a maximization problem with a multimodal objective function subject to partial order restrictions. In order to obtain the global optimal estimation of parameters, this paper presents a genetic algorithm and illustrates its effectiveness by some numerical examples.

关键词： genetic algorithm maximum likelihood estimates(MLE) partial ordered restrictions