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161.
162.
概述了指挥控制战的概念与产生的背景,讨论了电子战与指挥控制战的关系。  相似文献   
163.
164.
L.Chouanine  H.Eda  M.li  雍玲 《国防科技》1997,18(3):94-98
本文讲述了由PC机控制的多用途超精机床(MPUMT)的设计及光学镜平滑表面的加工。已研制出的机床可用于磨削、切削、研磨或抛光塑性状态下的硬脆材料。作为建立新的加工系统的关键部分,采用了大型磁致伸缩调节器(GMA),在没有放大器元件的情况下,它具有大功率的输出和大于压电陶瓷调节器几倍的纳米级的位移。切削DOC的深度和控制塑性状态过程的微塑性区域能够被调节器设置为具有高于1nm的精度,并能用金刚石磨削砂轮研磨。在当前研究中所用到的镜为多晶体、非晶体,也有加固玻璃。磨削实验的结果表明,已研制出来的超精机床能够实现对塑性状态下的玻璃和陶瓷材料的加工。材料特性参数和微裂纹之间的关系已被检测到,适用于大多数被研究玻璃的脆性到塑性磨削方式的转换已经确定。运用AFM、SEM和ZYGO对磨削表面进行了分析,例如BK7和TRC5(新材料;加固玻璃)的磨削表面分别具Ra=0.15nm和Ra=0.32nm的表面粗糙度。  相似文献   
165.
用矩阵法FTA 进行非单调关联系统的早期不交化   总被引:2,自引:0,他引:2       下载免费PDF全文
本文针对带有重复事件的非单调关联系统故障树,定义了非单调关联系统的割集矩阵及不交化最小割集矩阵,利用矩阵变换实现故障树的早期不交化,从而为求解复杂非单调关联系统,解决其NP困难问题,提供了一条新途径  相似文献   
166.
During the course of the last few years, attacks on the traveling salesman problem have resulted in a variety of often innovative and rather powerful computational procedures. In this article, we present a review of these results for problems defined on weighted and unweighted graphs. Some account of computational behavior for exact algorithms is provided; however, the primary coverage deals with the strategy of particular procedures. In addition, we include some aspects of nonexact algorithms with major interest confined to the establishment of worst-case bounds.  相似文献   
167.
In this paper a model is developed for determining optimal strategies for two competing firms which are about to submit sealed tender bids on K contracts. A contract calls for the winning firm to supply a specific amount of a commodity at the bid price. By the same token, the production of that commodity involves various amounts of N different resources which each firm possesses in limited quantities. It is assumed that the same two firms bid on each contract and that each wants to determine a bidding strategy which will maximize its profits subject to the constraint that the firm must be able to produce the amount of products required to meet the contracts it wins. This bidding model is formulated as a sequence of bimatrix games coupled together by N resource constraints. Since the firms' strategy spaces are intertwined, the usual quadratic programming methods cannot be used to determine equilibrium strategies. In lieu of this a number of theorems are given which partially characterize such strategies. For the single resource problem techniques are developed for determining equilibrium strategies. In the multiple resource problem similar methods yield subequilibrium strategies or strategies that are equilibrium from at least one firm's point of view.  相似文献   
168.
This paper investigates the effect of the optimal solution of a (capacitated) generalized transportation problem when the data of the problem (the rim conditions—i.e., the available time of machine types and demands of product types, the per unit production costs, the per unit production time and the upper bounds) are continuously varied as a linear function of a single parameter. Operators that effect the transformation of optimal solution associated with such data changes, are shown to be a product of basis preserving operators (described in our earlier papers) that operate on a sequence of adjacent basis structures. Algorithms are furnished for the three types of operators—rim, cost, and weight. The paper concludes with a discussion of the production and managerial interpretations of the operators and a comment on the “production paradox”.  相似文献   
169.
The design of a system with many locations, each with many items which may fail while in use, is considered. When items fail, they require repair; the particular type of repair being governed by a probability distribution. As repairs may be lengthy, spares are kept on hand to replace failed items. System ineffectiveness is measured by expected weighted shortages over all items and locations, in steady state. This can be reduced by either having more spares or shorter expected repair times. Design consists of a provisioning of the number of spares for each item, by location; and specifying the expected repair times for each type of repair, by item and location. The optimal design minimizes expected shortages within a budget constraint, which covers both (i) procurement of spares and (ii) procurement of equipment and manning levels for the repair facilities. All costs are assumed to be separable so that a Lagrangian approach is fruitful, yielding an implementable algorithm with outputs useful for sensitivity analysis. A numerical example is presented.  相似文献   
170.
This paper presents an algorithm for determining the upper and lower bounds for arc flows in a maximal dynamic flow solution. The procedure is basically an extended application of the Ford-Fulkerson dynamic flow algorithm which also solves the minimal cost flow problem. A simple example is included. The presence of bounded optimal are flows entertains the notion that one can pick a particular solution which is preferable by secondary criteria.  相似文献   
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