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911.
新中国成立以来,在不同的历史时期,党和国家领导人对军事战略规划及相关问题作出过一系列指示和重要论述.这些重要论述,对全面和深入地了解军事战略规划发展演变的历程,指导人民军队在新的历史时期更好地规划国防和军队建设,有效应对未来面临的多种安全威胁、完成多样化军事任务,具有重要的现实意义. 相似文献
912.
西藏和平解放后,西藏反动上层坚持分裂国家、维护封建农奴制度的反动立场,千方百计地阻挠、破坏和平解放西藏协议的实施,进行了一系列背叛和分裂祖国的活动.经过长期策划和准备,1959年3月10日,西藏上层反动分子借达赖喇嘛要到西藏军区机关驻地观看军区文工团演出之机,挑起事端,发动了全面武装叛乱. 相似文献
913.
The orienteering problem involves the selection of a path between an origin and a destination which maximizes total score subject to a time restriction. In previous work we presented an effective heuristic for this NP-hard problem that outperformed other heuristics from the literature. In this article we describe and test a significantly improved procedure. The new procedure is based on four concepts—center of gravity, randomness, subgravity, and learning. These concepts combine to yield a procedure which is much faster and which results in more nearly optimal solutions than previous procedures. 相似文献
914.
Approximation schemes for single‐machine scheduling with a fixed maintenance activity to minimize the total amount of late work 下载免费PDF全文
We consider the problem of scheduling n independent and simultaneously available jobs without preemption on a single machine, where the machine has a fixed maintenance activity. The objective is to find the optimal job sequence to minimize the total amount of late work, where the late work of a job is the amount of processing of the job that is performed after its due date. We first discuss the approximability of the problem. We then develop two pseudo‐polynomial dynamic programming algorithms and a fully polynomial‐time approximation scheme for the problem. Finally, we conduct extensive numerical studies to evaluate the performance of the proposed algorithms. © 2016 Wiley Periodicals, Inc. Naval Research Logistics 63: 172–183, 2016 相似文献
915.
本文在建立了地面雷达数据库的基础上,对空间平台所处的雷达信号环境进行了仿真研究。文中给出了部分仿真数学模型和仿真软件模块结构,并利用仿真软件对空间平台位置处的雷达信号功率流密度和各种分布特性等进行了仿真试验研究,给出了有意义的仿真试验结果 相似文献
916.
公民道德建设是落实"以德治国"战略的重大举措 总被引:2,自引:0,他引:2
要加强公民道德建设,首先必须认识这一建设的重要意义,这是调动每个公民自觉投身社会主义现代化建设事业的内在要求,是搞好各项工作的前提条件.公民道德建设是发展先进文化的重要内容,是提高全民素质的一项基础性工程,对弘扬民族精神和时代精神,形成良好的社会道德风尚,促进物质文明与精神文明协调发展,全面推进建设有中国特色社会主义伟大事业,具有十分重要的意义. 相似文献
917.
一、概述我校研制的新型的流量信号倍频器——LXB-I,是提高流量信号处理精度和分辨率的一种专用仪器。火箭发动机试车时的流量信号,其频率通常在40Hz~2KHz范围内,若直接加到微型机处理,计数时会带来±1Hz的误差,这对低频信号引起的相对误差是可观的。经LXB-I将流量信号频率提高10倍或100倍,便可相应提高测量精度10倍或100倍。本仪器也可用于一般的流量信号或转速测量,以提高分辨率及测量精度。 相似文献
918.
介绍了分布交互仿真技术的发展现状,对应用分布交互仿真技术进行作战理论研究的问题进行了探讨。 相似文献
919.
The G/G/R machine repair problem with M operating machines, S warm standby spares, and R repairmen is studied as a diffusion process. The steady-state equations are formulated as diffusion equations subject to two reflecting barriers. The approximate diffusion parameters of the diffusion equations are obtained (1) under the assumption that the input characteristics of the problem are defined only by their first two moments rather than their probability distribution function, (2) under the assumption of heavy traffic approximation, that is, when queues of failed machines in the repair stage are almost always nonempty, and (3) using well-known asymptotic results from renewal theory. Expressions for the probability density functions of the number of failed machines in the system are obtained. A study of the derived approximate results, compared to some of the exact results, suggests that the diffusion approach provides a useful method for solving complex machine-repair problems. 相似文献
920.
Trade-in programs have been widely adopted to enhance repeat purchase from replacement customers. Considering that a market consists of replacement and new segments, we study the joint and dynamic decisions on the selling price of new product (hereafter, “selling price”) and the trade-in price involved in the program. By adopting a vertical product differentiation choice model, we investigate two scenarios in this paper. In the base model, the manufacturer has sufficiently large production capacity to fulfill the customer demand. We characterize the structural properties of the joint pricing decisions and compare them with the optimal pricing policy under regular selling. We further propose a semi-dynamic trade-in program, under which the new product is sold at a fixed price and the trade-in price can be adjusted dynamically. Numerical experiments are conducted to evaluate the performance of the dynamic and semi-dynamic trade-in programs. In an extended model, we consider the scenario in which the manufacturer stocks a batch of new products in the beginning of the selling horizon and the inventory cannot be replenished. Following a revenue management framework, we characterize the structural properties with respect to time period and inventory level of new products. 相似文献