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51.
简单回顾了国内外在火电机组运行优化领域的研究历程,列举了目前国内外市场上针对火电机组的各种主流运行优化产品的功能特点和应用情况,分析了国外引进产品和国内自主研发产品在中国当前市场环境下各自的优势和劣势。介绍了当前运行优化系统在国内电站机组的应用现状,阐述了国内外运行优化系统在实际应用中存在的问题,并提出了相应的改进意见。对机组运行优化系统的未来发展进行了展望,指出机组运行优化系统将利用先进技术设备和信息平台,与电站管理紧密结合,在日益规范的市场中不断发展完善,为提高电站经济性发挥更大的作用。 相似文献
52.
阐述了传统管理模式的生存条件及其弊端,对疏浚吹填工程推行项目经理责任承包制管理模式进行了探讨. 相似文献
53.
An outline of the characteristics of PEEK and the versatility of its compositional forms (micro and macro composites) are given to illustrate its wide potential for success in engineering applications. Although it is necessary to have particular tabulations of mechanical properties for engineering design, these are seldom available and consequently it is argued that an understanding of stiffness, toughness and strength properties are required to fully exploit available manufacturer's data and thus develop the full potential of PEEK and its composites. Stiffness characteristics are considered in terms of a modulus function which is dependent on time under load and temperature. In its composite forms, whether reinforced with short or continuous fibres, stiffness anistropy can be both considerable and complex, but some empirical ground-rules are apparent. For continuous fibre composites even in the form of complex lay-ups, it is also possible to attempt some stiffness prediction from certain pseudo-elastic constants. Toughness of PEEK and its composites is described in terms of both comparative and intrinsic properties. Instrumented falling weight impact data, particularly as a function of temperature enable some insight into ductile-brittle transitions for the unreinforced material, but crack initiation and crack propagation processes for the various fibre reinforced forms. Intrinsic toughness is described in terms of linear elastic fracture mechanics theory. Strength properties are described for static and dynamic loading configurations. In particular, PEEK and its composites are evaluated for increasing test severities for strength characteristics; stress concentration, loading form and test temperature are considered. 相似文献
54.
A very simple algorithm for computing all k nearest neighbors in 2-D is presented. The method does not rely on complicated forms of tessellation, it only requires simple data binning for fast range searching. Its applications range from scattered data interpolation to reverse engineering. 相似文献
55.
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57.
Electronic commerce is an important application that has evolved significantly recently. However, electronic commerce systems
are complex and difficult to be correctly designed. Guaranteeing the correctness of an e-commerce system is not an easy task
due to the great amount of scenarios where errors occur, many of them very subtle. In this work we presents a methodology
that uses formal-method techniques, specifically symbolic model checking, to design electronic commerce applications and to automatically verify them. Also, a model checking pattern hierarchy has
been developed—it specifies patterns to construct and verify the formal model of e-commerce systems. We consider this research
the first step to the development of a framework, which will integrate the methodology, an e-commerce specification language
based on business rules, and a model checker.
Adriano Pereira received the B.S. and M.S. degrees in computer science in 2000 and 2002, respectively, and he is currently pursuing the Ph.D.
degree in computer science from the Federal University of Minas Gerais, Belo Horizonte, Brazil. His current interests are
on performance analysis and modeling of e-business and distributed systems, and formal methods.
Mark Song received the B.S., M.S. and Ph.D. degrees in computer science from the Federal University of Minas Gerais, Belo Horizonte,
Brazil. His current interests are on distributed systems and formal methods – especially BMC (Bounded Model Checking).
Gustavo Franco received the B.S. and M.S. degrees in computer science in 2001 and 2004, respectively, from the Federal University of Minas
Gerais, Belo Horizonte, Brazil. His research was on modeling the user behavior of e-business and distributed systems, and
formal methods. Actually his current interests are on software engeneering and project management of IT projects. 相似文献
58.
随着西北勘测设计研究院(以下简称西北院)勘测总队所承担的黄河龙 ̄青段、白龙江流域等河段前期综合勘测工作的相继结束,拥有2000多名职工的勘测队伍面临着何去何从的重大选择。在此转折关头,勘测总队面对现实,审时度势,抓住机遇,开拓前进,及时转轨变型,制定了本单位发展的战略和方向,使勘测总队由单一勘测业务转变为集勘测与岩土工程施工为一身的新型综合队伍。几年来,经过全体职工的奋发努力,缍获得了1995年 ̄ 相似文献
59.
多判据模糊决策在工程爆破中的应用 总被引:3,自引:0,他引:3
本文介绍了多判据模糊决策的数学模型。该模型可广泛地用于工程爆破中的爆破方案比较,以及爆破试验中的最优爆破参数的决策。该模型的应用将有利于工程爆破试验及设计的计算机程序设计。 相似文献
60.
本文简要地介绍了我国几个地下矿在锚喷网联合支护的硐室工程中堵漏防渗处理所取得的良好效果,可供类似矿山参考。 相似文献