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101.
Mohd Amin AT-TASNEEM Sallehuddin Mohamed HARIS Zulkifli Mohd NOPIAH 《浙江大学学报(英文版)(C辑:计算机与电子)》2012,13(10)
The problem of finding stabilizing controllers for switched systems is an area of much research interest as conventional concepts from continuous time and discrete event dynamics do not hold true for t... 相似文献
102.
Nataliya Chekhova 《Theoretical computer science》2000,230(1-2)
For an irrational rotation, we use the symbolic dynamics on the sturmian coding to compute explicitly, according to the continued fraction approximation of the argument, the measure of the largest Rokhlin stack made with intervals, and the measure of the largest Rokhlin stack whose levels have one name for the coding. Each one of these measures is equal to one if and only if the argument has unbounded partial quotients. 相似文献
103.
本文根据场相关定理,应用几何绕射理论(GTD),分析计算主面为抛物面,副面为任意旋转对称面的微波双反射面天线效率.通过实际证实,运算简明,效果良好. 相似文献
104.
Several companies offer computation on demand for a fee. More companies are expected to enter this business over the next decade, leading to a marketplace for computation resources. Resources will be allocated through economic mechanisms that establish the relative values of providers and customers. Society at large should benefit from discoveries obtained through the vast computing power that will become available. Given such a computation marketplace, can economics-based resource allocation provide benefits for providers, customers and society? To investigate this question, we simulate a Grid economy where individual providers and customers pursue their own ends and we measure resulting effects on system welfare. In our experiments, customers attempt to maximize their individual utilities, while providers pursue strategies chosen from three classes: information-free, utilization-based and economics-based. We find that, during periods of excess demand, economics-based strategies yield overall resource allocation that benefits system welfare. Further, economics-based strategies respond well to sudden overloads caused by temporary provider failures. During periods of moderate demand, we find that economics-based strategies provide ample system welfare, comparable with that of utilization-based strategies. We also identify and discuss key factors that arise when using economic mechanisms to allocate resources in a computation marketplace. 相似文献
105.
People around the world have shaped societies and urban spaces around water for millennia. They have transformed natural water structures and patterns to serve their diverse needs. The ways in which historical decisions affect contemporary water systems and influence future planning of urban systems still need to be fully recognized. This paper explores the multiple roles of water systems in Chang'an during the Western Han Dynasty. Chang’an, one of the ancient names for the city of Xi’an, was a typical capital city of China and East Asia in early ancient times. This study explores everyday practices pertaining to water as well as its role in defense, gardening, politics and culture.Drawing upon three historical theories, this study presents findings that water was embedded in the design of traditional Chinese capitals. The siting and construction of capital cities was first based on the Theory of Choosing the Center (3rd century BCE) and the Theory of Conforming to Nature (5th–3rd century BCE). However, the final maturation of this urban morphology, including the water system, was closely related to the Theory of Symbolizing and Modeling Heaven and Earth (4th–3rd century BCE), in a way that manifested the imperial power's organization and control of space and time.Through close analysis of historical documents, archaeological reports and modern investigations, the paper aims to clarify, analyze and summarize the historical context and evolution, functional and structural characteristics, as well as the economic, political, cultural and military connotations of water systems in Chang'an. It argues that the coordination of urban construction and the water environment was a key foundation for capital city development. It proposes that people shaped urban water supply in many ways, including daily life, waterway transportation, agricultural irrigation, aquaculture promotion, military defense and fire prevention.The water system in Chang'an also provided an important place for royalty and nobility to go fishing, to hunt and to engage in leisure and naval training. The landscape with this water system as the core, including Taiye Lake and Kunming Lake, had also inspired Chinese gardening history, and had a profound impact on future generations. More importantly, the capital's urban morphology design was a miniature of the world recognized by the monarch, as well as the symbolic image of the supreme rulers' political and cultural desire to control and possess Tianxia, which essentially means the whole world. In conclusion, the paper calls for a closer study of water-based design as a foundation for urban planning. 相似文献
106.
Yanhe Li Xianwu Guo Liping Chen Xiaohui Bai Xinlan Wei Xiaoyun Zhou Songqian Huang Weimin Wang 《International journal of molecular sciences》2015,16(7):14623-14639
Identifying the dispersal pathways of an invasive species is useful for adopting the appropriate strategies to prevent and control its spread. However, these processes are exceedingly complex. So, it is necessary to apply new technology and collect representative samples for analysis. This study used Approximate Bayesian Computation (ABC) in combination with traditional genetic tools to examine extensive sample data and historical records to infer the invasion history of the red swamp crayfish, Procambarus clarkii, in China. The sequences of the mitochondrial control region and the proPOx intron in the nuclear genome of samples from 37 sites (35 in China and one each in Japan and the USA) were analyzed. The results of combined scenarios testing and historical records revealed a much more complex invasion history in China than previously believed. P. clarkii was most likely originally introduced into China from Japan from an unsampled source, and the species then expanded its range primarily into the middle and lower reaches and, to a lesser extent, into the upper reaches of the Changjiang River in China. No transfer was observed from the upper reaches to the middle and lower reaches of the Changjiang River. Human-mediated jump dispersal was an important dispersal pathway for P. clarkii. The results provide a better understanding of the evolutionary scenarios involved in the rapid invasion of P. clarkii in China. 相似文献
107.
本文建立了一个较为准确的应用于糖厂的热能压缩器的计算模型。通过对该模型的最优化计算,可获得热能压缩器的最佳工况条件。 相似文献
108.
109.
《国际计算机数学杂志》2012,89(3):273-284
The reverse Polish notation (RPN) is a well-known method for the expression notification in a postfix manner, instead of using the usual infix notation. Authors made a method for symbolic computation based on RPN. This method is successfully applied on a number of problems. In this article, there is a brief survey of these applications. In addition, the application of the method on algebraic computation of unary pairfunctions is presented. 相似文献
110.