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961.
LIU Bi-Yu~ 《自动化学报》2005,(5)
Based on design of an observer,the issue of dynamic output feedback control is studied for uncertain discrete systems with delays.A comparison theorem is given for nonlinear uncertain discrete systems with multiple time delays.Based on the comparison theorem with some inequalities, some delay-independent sufficient conditions for the robust stabilization of the systems are presented by means of output feedback. 相似文献
962.
Guaranteed Cost Control for Discrete-time Singular Large-scale Systems with Parameter Uncertainty 总被引:1,自引:0,他引:1
WO Song-Lin~ 《自动化学报》2005,(5)
The problem of optimal guaranteed cost control for discrete-time singular large-scale systems with a quadratic cost function is considered in this paper.The system under discussion is subject to norm bounded time-invariant parameter uncertainty in all the matrices of model.The problem we address is to design a state feedback controller such that the closed-loop system not only is robustly stable but also guarantees an adequate level of performance for all admissible uncer- tainties.A sufficient condition for the existence of guaranteed cost controllers is presented in terms of linear matrix inequalities(LMIs),and a desired state feedback controller is obtained via con- vex optimization.An illustrative example is given to demonstrate the effectiveness of the proposed approach. 相似文献
963.
1 IntroductionThere are mainly three kinds of circuit faults:components' fault, PCB' s (Printed Circuit Board)fault and assemblage fault. Among them, PCB' s faultaccounts for half of all. Generally speaking, PCB' sfault comes into being in the manufacturing process andthe most common forms of the fault include the short ofconductors in different nets and the open of conductorsin the same net. There will be economy loss if we solderthe electron components on a PCB with fault. So, it isve… 相似文献
964.
Technora,madefromaramidfibersandsome whatsimilartothecommonlyknowKevlar,and Ultrahighlyorientedhighmolecularweightpolyeth ylene UHMWPEfibersarealloftenusedinflexible armourapplicationsandhencesubjectedtohighrates ofloading.Theutilizationoftheirreinforcedcom positesarmourincertainballisticapplicationsisin creasinglypreferredoverconventionalrigidmetalar moursystemsbecauseofitssuperiorstrength to weightratioandflexibility.Todate,thedesignand developmentofsuchfabricarmoursystemshave largelybeen… 相似文献
965.
Improvement of Fracture Toughness Lanthanum Zirconate 总被引:1,自引:0,他引:1
Thermalbarriercoatings(TBCs)havefoundan increasingnumberofapplicationsinprotectinghigh temperaturemetalliccomponents,forexample,TBCsaredepositedontransitionpieces,combustion lines,first stagebladesandvanes,andotherhot pathcomponentsofgasturbineseithertoincreasethe inlettemperaturewithaconsequentimprovementof theefficiencyortoreducetherequirementsfora coolingsystem[1].Thereareseveralceramicsthat havebeenevaluatedasTBCmaterials[2].Lanthanum zirconatewasrecentlyproposedasapromisingTBC materia… 相似文献
966.
Duetotheirhighstrength,modulusandfracture toughnessaswellasgoodadhesionandthermalre sistance[1],epoxyresinsasmatricesarewidelyused inaeronautics,astronautics,transportation,sports andotherindustry.Standardepoxyresinsareusually basedonDGEBA(diglycidyletherofbisphenolA),whichneedsactivehydrogenorotheractivegroupsto opentwoepoxyrings.Four functionalepoxylike TGMDA(tetraglycidylmethylenedianiline)isoften usedforhigh performanceepoxymatrixcomposites becauseofitsrelativelyhighercross linkingdens… 相似文献
967.
移动数据业务--运营商的利润增长点 随着用户消费需求的变化和移动通信网络的迅速发展,数据业务的增长尤为迅速.移动数据业务收入在运营商总收入中所占的比例不断攀升,开发增值业务也成为运营商新的经济增长点. 相似文献
968.
Zhimin ZHOU Yong ZHOU Mingjun WANG Chunsheng YANG Ji''''an CHEN Wen DING Xiaoyu GAO Taihua ZHANG Key Laboratory for Thin Film Microfabrication Technology of Ministry of Education Research Institute of Micro/Nanometer Science Technology Shanghai Jiao Tong University Shanghai China State Key Laboratory of Nonlinear Mechanics 《材料科学技术学报》2006,22(3)
Microbridge testing was used to measure the Young's modulus and residual stress of metallic films. Samples of freestanding NiFe film microbridge were fabricated by microelectromechanical systems. Special ceramic shaft structure was designed to solve the problem of getting the load-deflection curve of NiFe film microbridge by the Nanoindenter XP system with normal Berkovich probe. Theoretical analysis of load-deflection curves of the microbridges was proposed to evaluate the Young's modulus and residual stress of the films simultaneously. The calculated results based on experimental measurements show that the average Young's modulus and residual stress for the electroplated NiFe films are 203.2 GPa and 333.0 MPa, respectively, while the Young's modulus measured by the Nano-hardness method is 209.6±11.8 GPa for the thick NiFe film with silicon substrate. 相似文献
969.
随着电信市场竞争的加剧以及用户对数据业务需求的不断扩大,电信运营商加快了迈向基于IP的下一代网络(IPNGN)的步伐,希望通过构建融语音、数据、视频于一体的下一代网络,快速部署创新的业务和应用,同时有效降低整体拥有成本.为此,电信运营商需要融合基础设施,在提高现有业务供应水平的同时,为未来的业务提供生命力更长久的框架,并且拥有提供增值化和个性化业务的手段,最终为用户带来全新的通信体验. 相似文献
970.
作为持续多年的行业热点,业界对3G宽带无线数据业务应用的讨论开始超过其他热点,几乎成了3G的代名词。无线宽带数据业务的最早应用始于韩国和日本,在这两个国家商用后,市场反应热烈,用户发展迅速,取得了巨大的成功。韩国1x EV—DO数据用户的ARPU是1xRTT的4倍以上,而在日本,NTT DoCoMo的数据业务收入占到了27%以上,成为新的利润增长点。 相似文献