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101.
Bingyong Yan Zuohua Tian Songjiao Shi 《International Journal of Electrical Power & Energy Systems》2008,30(5):343-360
In this paper, we propose a novel distributed robust fault detection and identification (RFDI) scheme for a class of nonlinear systems. Firstly, a detection and identification estimator—robust fault tracking approximator (RFTA) is designed for online health monitoring. A novel feature of the RFTA is that it can simultaneously detect and accurately identify the shape and magnitude of the fault and disturbance. Moreover, it takes less online training time compared with the traditional neural network based fault diagnosis schemes. For some distributed systems, a network of distributed estimators is constructed where the RFTA is embedded into each estimator. Then we use consensus filter to filter the outputs of each estimator. One of the most important merits of the consensus filter is that its outputs can dramatically improve the accuracy of fault detection and identification. Next, the stability of the distributed RFDI scheme is rigorously investigated. Finally, two numerical examples are given to illustrate the feasibility and effectiveness of the proposed approach. 相似文献
102.
高压线走廊下建设大型公共绿地的探索 总被引:2,自引:0,他引:2
通过闵行经济技术开发区范围内高压线走廊下的40万m~2非生产性用地建设成大型公共绿地的实践,提出了“以绿养园,以园养园”的新思路,充分体现“谁种养,谁保护,谁得益”的原则,给上海地区乃至全国开发利用高压线走廊下的土地资源,提供了借鉴。 相似文献
103.
利用寿命周期评价的思想,计算了炼铁生产过程中的环境负荷,并分析了各因素对环境负荷的影响,运用神经网络对炼铁生产过程环境负荷进行了预测。 相似文献
104.
Agglomeration and networks in spatial economies 总被引:1,自引:0,他引:1
We consider the parallel developments in the economics of agglomeration and the economics of networks. We explore the complementarities between the productivity benefits of agglomeration and those of network linkages, arguing that networks of actors dispersed over space may substitute for agglomerations of actors at a single point.JEL Classification:
D20, L14, R30 相似文献
105.
The use of neural networks as global approximation tool in crashworthiness problems is here investigated. Neural networks are not only asked to return some meaningful indices of the structural behavior but also to reproduce load-time curves during crash phenomena. To contain the number of examples required for the training process, parallel subsystems of small neural networks are designed. Design points for the training process are obtained by explicit finite element analyses performed by PAMCRASH. The settlement of the points in the design domain is defined using a maximum distance concept. The procedure is applied to different typical absorption structures made of aluminum alloy: riveted tubes, honeycomb structures, longitudinal keel beam and intersection elements of helicopter subfloors. 相似文献
106.
TCP/IP网络的动态模型描述 总被引:2,自引:0,他引:2
拥塞现象成为TCP/IP网络发展面临的一个重要问题。因此,拥塞控制对TCP/IP网络的鲁棒性和稳定性具有重要作用。目前,网络拥塞控制策略主要包括两类:端到端的控制机制,如TCP拥塞控制算法;网络内部的主动队列管理(AQM)策略。但由于缺乏对网络系统动态特性的了解,这些拥塞控制策略大都基于专家经验,并没有建立完整的理论分析框架。为此,本文从数据流的角度出发,通过建立网络基本单元状态方程模型来实现IP网络系统的数学解析模型,然后用混杂系统来描述TCP带有拥塞控制策略的数据传输过程,建立了TCP/IP网络的动态模型,为网络系统中动态性能的分析、拥塞控制策略的设计奠定了基础。实验结果表明,该数学模型与NS仿真实验的结果相一致。 相似文献
107.
108.
作为公民共同行为有机组成部分的公益诉讼的本质决定了律师参与公益诉讼是尽公民之本分,而作为具有为公众服务精神的律师政治家这一律师职业理想的要求,又决定了律师参与公益诉讼是律师职业特有品格的体现,是律师和律师职业真正获得尊重的基础。结合公益诉讼的现实,从立法上肯定律师参与公益诉讼的主体地位,既可保证律师实现社会正义这一价值追求,又可保证实现公益诉讼的理想效果。 相似文献
109.
Comments on an article by Bushman and Anderson (see record 2001-17729-001). We are concerned that Bushman and Anderson's article on media violence contains data that are incorrect or irreproducible. This is a serious issue; the article has already been referenced by numerous other formal papers according to a Google scholarly article search as well as in a statement to the U.S. Senate, in legal proceedings, and in California State law (Assembly Bill 1179 in 2005). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
110.
Gouvier W. Drew; Sytsma-Jordan Sara; Mayville Stephen 《Canadian Metallurgical Quarterly》2003,48(3):175
Objective: To evaluate the effects of disability type, job complexity, and public contact on hiring decisions. Design and Participants: An Americans With Disabilities Act (ADA; 1990) fact sheet and matched resumes with vocational and medical histories including chronic mental illness, developmental disability, closed head injury, and back injury were provided to 295 undergraduate business-related majors, who rated the applicants' suitability for 2 job positions and work shifts. Results: Findings indicated disparities in ratings of employability as a function of disability type. Paired comparisons yielded complementary findings, with effects of disability type and Disability Type × Job Complexity, but no effects of public contact. Conclusions: Stereotyping and discrimination in employment decisions apparently persist, more than 10 years after the ADA. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献