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211.
各类卫星在现代战争中发挥着重要和关键作用。我国传统的卫星试验和鉴定具有很强的科研试验性质,承制单位和用户重点关注的是性能检验,较少考虑作战效能和部队适用性等指标。为推动卫星装备建设和应用,装备试验鉴定部门初步组织开展了相应的在役考核工作。文章对比了美军装备作战试验与鉴定、我国作战试验与在役考核的概念;提出卫星在役考核的六大特点;分析卫星在役考核的组织方式、组织机构和组织保障的不足,提出相应发展建议;研究卫星在役考核指标体系设计、分析评估方法、问题反馈与整改等方面的不足,并提出相应措施建议。 相似文献
212.
侯思祥 《国防科技大学学报》1988,10(3):88-92 ,115
本文从系统的观点出发,对n-人非合作对策的解点作了探讨,提出了两类新的Nash平衡点的精选,并证明了其存在性。这两种Nash平衡点分别称之为第一类Nash平衡点和第二类Nash平衡点。第一类Nash平衡点具有冒险性,第二类Nash平衡点具有保守性,二者都满足整体上的最优性。 相似文献
213.
习主席站在时代发展与战略全局的高度,着眼军队建设全局,深刻阐述了科技兴军在强军征程中的重要作用,明确了科技兴军的举措抓手,丰富和发展了新时代党的强军思想理论体系。必须毫不动摇地坚持走中国特色科技兴军之路,为实现党在新时代的强军目标提供强有力的支撑。 相似文献
214.
We show the existence of a unique analytic single parameter limiting survival function arising from the repeated composition of a coherent structure as the number of components tends to infinity. Examples include the repeated composition process of the bridge structure. © 2003 Wiley Periodicals, Inc. Naval Research Logistics, 2004. 相似文献
215.
序列图像中运动点目标轨迹的实时检测算法,是目标识别、实时跟踪处理系统中的关键算法之一。在分析不同层次处理方法的基础上,给出了一种基于预测、窗口匹配的点轨迹预测—匹配检测算法,并根据仿真实验的效果,指出此算法可有效地对低信噪比序列图像运动点目标轨迹进行实时检测,具有多目标轨迹检测能力。 相似文献
216.
We address infinite‐horizon models for oligopolies with competing retailers under demand uncertainty. We characterize the equilibrium behavior which arises under simple wholesale pricing schemes. More specifically, we consider a periodic review, infinite‐horizon model for a two‐echelon system with a single supplier servicing a network of competing retailers. In every period, each retailer faces a random demand volume, the distribution of which depends on his own retail price as well as those charged by possibly all competing retailers. We also derive various comparative statics results regarding the impact several exogenous system parameters (e.g., cost or distributional parameters) have on the equilibrium decisions of the retailers as well as their expected profits. We show that certain monotonicity properties, engrained in folklore as well as in known inventory models for centralized systems, may break down in decentralized chains under retailer competition. Our results can be used to optimize the aggregate profits in the supply chain (i.e., those of the supplier and all retailers) by implementing a specific wholesale pricing scheme. © 2003 Wiley Periodicals, Inc. Naval Research Logistics, 2004. 相似文献
217.
传统的图像边缘检测算子一般都只能得到多像素宽边缘,这为后续的图像处理带来了一定困难。结合边缘走向趋势的估计技术以及对连通关键点判断的方法,提出了一种新型的边缘细化算法———保持连通的边缘细化算法。该算法能在保持边缘原有信息(连通和走向)的前提下,以较小的计算开销,给出理想的或是可接受的单像素宽细化结果。 相似文献
218.
This article analyzes dual sourcing decisions under stochastically dependent supply and demand uncertainty. A manufacturer faces the trade‐off between investing in unreliable but high‐margin offshore supply and in reliable but low‐margin local supply, where the latter allows for production that is responsively contingent on the actual demand and offshore supply conditions. Cost thresholds for both types of supply determine the optimal resource allocation: single offshore sourcing, single responsive sourcing, or dual sourcing. Relying on the concept of concordance orders, we study the effects of correlation between supply and demand uncertainty. Adding offshore supply to the sourcing portfolio becomes more favorable under positive correlation, since offshore supply is likely to satisfy demand when needed. Selecting responsive capacity under correlated supply and demand uncertainty is not as straightforward, yet we establish the managerially relevant conditions under which responsive capacity either gains or loses in importance. Our key results are extended to the broad class of endogenous supply uncertainty developed by Dada et al. [Manufact Serv Operat Mange 9 (2007), 9–32].© 2012 Wiley Periodicals, Inc. Naval Research Logistics, 2012 相似文献
219.
基带信号码元同步抽取是目前星载AIS(Automatic Identification System)信号处理中的一个难点问题,针对过零检测和迟门早门等现有算法存在的不足,提出了基于能量度量的基带信号自适应码元同步抽取算法。将基带信号根据采样率和码速率的比值分割成相同的段的组合,之后分别计算每个段内相应样点的能量度量,最后选择使能量度量最大时的样点集作为最优同步抽取样点,该样点集具有最大信噪比。仿真结果验证了该算法误码率优于过零检测和迟门早门算法。 相似文献
220.
We consider the problem of identifying the simulated system with the best expected performance measure when the number of alternatives is finite and small (often < 500). Recently, more research efforts in the simulation community have been directed to develop ranking and selection (R&S) procedures capable of exploiting variance reduction techniques (especially the control variates). In this article, we propose new R&S procedures that can jointly use control variates and correlation induction techniques (including antithetic variates and Latin hypercube sampling). Empirical results and a realistic illustration show that the proposed procedures outperform the conventional procedures using sample means or control variates alone. © 2012 Wiley Periodicals, Inc. Naval Research Logistics, 2012 相似文献