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41.
不确定多时滞奇异系统鲁棒H∞降维滤波器的设计   总被引:1,自引:0,他引:1  
讨论了一类同时具有不确定性和多时滞的奇异系统鲁棒H∞降维滤波器的设计问题.目的是对于所容许的不确定性和多时滞,设计一个比原系统维数低的确定维数的稳定线性滤波器,使得滤波误差动态系统是渐进稳定并满足给定的H∞性能要求.该问题有解的充分条件是0≤ETY,rankX≤,Π1<0,Π2<0;并且当这些条件满足时,以参数显式化的形式给出了所求的鲁棒H∞降维滤波器.所有这些结果都只利用了原始系统的矩阵而没有分解,这就使得设计过程简便、直接.最后用数值算例验证了结论的可行性和有效性.  相似文献   
42.
提出了一种基于纳米金属与有机分子共掺杂超分子结构光电子材料的设计组装新方法.通过分子在球形金属纳米粒子表面吸附形成的超分子结构实现金属纳米粒子对分子的激发,进而达到分子功能增强与扩展.讨论了材料设计过程中的几个关键问题,设计并合成出具有短波长光存储特性复合材料薄膜.实验表明,与单纯由甲基橙掺杂复合膜相比,甲基橙在具有超分子结构的复合膜中,最大吸收波长蓝移约23 nm,复合膜迅速分解的初始温度和分解温度带的范围分别提高和降低41℃和51℃.表明以这种思路设计组装光电子功能复合材料的方法有效可行.  相似文献   
43.
建筑设计构思的文化表现   总被引:1,自引:1,他引:0  
许跃  王益 《工程与建设》2008,22(2):179-180
针对建筑设计构思中如何表现文化的问题,进行了理性的分析,明确了建筑文化的概念及如何在建筑设计构思中表现,并指出建筑是一个时代的写照,建筑要用自己特殊的文化语言,来表达所处的时代实质.  相似文献   
44.
对TD-SCDMA基站的无线网络勘察设计的思考   总被引:1,自引:0,他引:1  
TD-SCDMA基站的无线网络勘察设计是TD-SCDMA系统设计的重要组成部分,直接影响无线网络的性能和建设成本.介绍了勘察流程、站址选择、基站勘察设计等方面的内容,对相关的通信设计人员提供了一定的指导意义.  相似文献   
45.
Migrant resettlement is essential to the success of the Three Gorges Project (TGP),and the smooth implementation of resettlement is ensured by the resettlement planning and effective organization management.In the process of resettlement planning and implementation,systematic legislation and document support system is established;environmental capacity analysis and assets appraisal methods are introduced;resettlement sites are selected through in-depth analysis and comparison;the relationship between resettlement compensation and local development is correctly understood and considered,and reasonable resettlement schedules are well prepared.Through the establishment of efficient management system and capital management mode of "static control and dynamic management",as well as the timely adjustment of plan according to actual situations,the resettlement is accomplished smoothly.Thus,the social stability of the reservoir area is ensured;the economic development of reservoir area is promoted,and it has promoted successfully the improvement of legislation,regulations and techniques for land requisition and resettlement.The paper also discusses the theory and prospective work of resettlement.  相似文献   
46.
Beijing-Tianjin intercity railway is the first newly-built passenger dedicated line with operating speed of 350 km/h in our country. During design,new ideas of bridge construction were carried out to ensure the requirements of safety,comfort and stability of the train under high-speed condition. At the same time,concepts of environmental adaptability,service to transportation and comprehensive benefits were observed. On the whole line,long-bridge schemes were adopted and the most advanced technologies of unballasted track were utilized on bridges,the length of which accounts for 87.7 % of the total line. The success of design and construction of the bridges on this rail has accumulated valuable experience for high-speed railway construction on a large scale in the future,and made it a marking,demonstrating,and model project to follow.  相似文献   
47.
:Based on the principles of molecular engineering, a series of new chromophores with high second-or der nonlinear optical(NLO)activities have been designed for achieving a trade-off of the nonlinearity-transparency-ther mal stability. The NLO properties of these chromophores have been investigated theoretically by employing the AMI/Fi nite Field approach. It is found that the calculated μβ0 values of some designed chromophores can reach the magnitude of 10-45 esu, and the highest decomposition temperature Td can be as high as 377℃, the highest glass transition tem perature Ts of their donor-embedded addition-type polyimides can be as high as 324℃.  相似文献   
48.
Struts是使用servlet和JavaServer Pages技术的一种Model-View-Controller实现.Struts为Java Web应用提供了现成的通用框架,可以大大提高Web应用的开发速度.同时通过一个例子来介绍用Struts实现MVC机制的Web应用.  相似文献   
49.
An effort was made to design an age hardening Mg-Li alloy based on the phase diagrams calculated by means of "THERMO-CALC"—a thermodynamic software. Experiments were carried out to verify the calculated results by melting the alloy and examining its structure and aging behavior. The results show that the alloy possesses a structure constituent as expected, besides, the alloy has apparent aging behavior and over aging happens even at lower temperature. Metastable (Mg, Li, Al, Zn) phase has been identified when the hardness reaches the aging peak. With the increase of the aging time, (Mg, Li, Al, Zn) phase transforms to stable α phase and over aging happens.  相似文献   
50.
结合土木工程毕业设计的实际,加强对学生个性化发展和创造性潜能的培养;以学生为主体增强选题、择师的自主性、灵活性,充分调动和激发学生学习的主观能动性和创造性;建立健全各项条件保障、激励约束和监督机制,进一步完善教学质量保障体系的建设.  相似文献   
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