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291.
提出了一种基于传感器网络的目标定位系统的模型,利用PtolemyⅡ建模仿真平台完成该传感器网络目标定位系统的系统级行为描述,同时对该目标定位系统进行建模与仿真,分析了传感器网络目标定位系统的诸多影响因素,并对仿真模型进行了命中率性能测试。测试结果表明,传感器网络目标定位系统对于传感器节点的功耗及信息时间同步窗口具有敏感性,符合传感器网络目标定位系统应用特性,Ptolemy嵌入式系统级设计方法学对指导传感器网络系统设计具有重要意义。 相似文献
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Gamma accelerated degradation tests (ADT) are widely used to assess timely lifetime information of highly reliable products with degradation paths that follow a gamma process. In the existing literature, there is interest in addressing the problem of deciding how to conduct an efficient, ADT that includes determinations of higher stress‐testing levels and their corresponding sample‐size allocations. The existing results mainly focused on the case of a single accelerating variable. However, this may not be practical when the quality characteristics of the product have slow degradation rates. To overcome this difficulty, we propose an analytical approach to address this decision‐making problem using the case of two accelerating variables. Specifically, based on the criterion of minimizing the asymptotic variance of the estimated q quantile of lifetime distribution of the product, we analytically show that the optimal stress levels and sample‐size allocations can be simultaneously obtained via a general equivalence theorem. In addition, we use a practical example to illustrate the proposed procedure. 相似文献
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本文以太行解放区为考察中心,在对相关史料进行解读的基础上论述了老区土改所引发的全面而深刻的社会变革:经济方面,满足了农民"耕者有其田"的愿望,提高了民众的生活水平,激发了民众的生产热情;政治方面,通过整党运动,转变了党员干部的工作作风,调整了基层党支部的构成,使基层民主政权得以巩固和发展;社会方面,移风易俗,在冲击旧有思想观念的同时塑造了新的社会风气。 相似文献
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Parallel machine scheduling with batch deliveries to minimize total flow time and delivery cost 下载免费PDF全文
Motivated by the flow of products in the iron and steel industry, we study an identical and parallel machine scheduling problem with batch deliveries, where jobs finished on the parallel machines are delivered to customers in batches. Each delivery batch has a capacity and incurs a cost. The objective is to find a coordinated production and delivery schedule that minimizes the total flow time of jobs plus the total delivery cost. This problem is an extension of the problem considered by Hall and Potts, Ann Oper Res 135 (2005) 41–64, who studied a two‐machine problem with an unbounded number of transporters and unbounded delivery capacity. We first provide a dynamic programming algorithm to solve a special case with a given job assignment to the machines. A heuristic algorithm is then presented for the general problem, and its worst‐case performance ratio is analyzed. The computational results show that the heuristic algorithm can generate near‐optimal solutions. Finally, we offer a fully polynomial‐time approximation scheme for a fixed number of machines. © 2016 Wiley Periodicals, Inc. Naval Research Logistics 63: 492–502, 2016 相似文献
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This article provides a modeling framework for quantifying cost and optimizing motion plans in combat situations with rapid weapon fire, multiple agents, and attacker uncertainty characterized by uncertain parameters. Recent developments in numerical optimal control enable the efficient computation of numerical solutions for optimization problems with multiple agents, nonlinear dynamics, and a broad class of objectives. This facilitates the application of more realistic, equipment‐based combat models, which track both more realistic models, which track both agent motion and dynamic equipment capabilities. We present such a framework, along with a described algorithm for finding numerical solutions, and a numerical example. 相似文献
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嵌入式仿真技术系统就是"虚拟仿真实现在实装上,在实装上实施虚拟仿真",具有真实感强、时效性好、针对性强、跨度大、有利于决策指挥、效费比高的特点。嵌入式仿真在水面舰艇、装甲兵、炮兵、反坦克导弹分队、武警部队训练及战役模拟训练中都有应用。美军应用嵌入式仿真系统推动训练实现了全面转型。 相似文献
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