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161.
协同仿真环境的设计与实现 总被引:1,自引:0,他引:1
本文从计算机技术和仿真技术的发展和应用需求出发,提出了协同仿真的基本概念和关键技术,包括建模方法、仿真算法、仿真数据库等几个方面。讨论了协同仿真环境的一般体系结构,最后,介绍了一种协同仿真环境的设计和实现方法。 相似文献
162.
基于关系数据库的仿真模型管理 总被引:3,自引:0,他引:3
本文将讨论仿真模型库管理技术。从仿真模型库管理的实际需求出发,提出以关系代数系统实体结构(RASES)框架为理论依据、利用关系数据库进行模型库管理的方法,并给出模型库管理算法的形式化描述及系统设计。 相似文献
163.
Victoria L. Zhang 《海军后勤学研究》1996,43(5):691-708
This article explores ordering policies for inventory systems with three supply modes. This model is particularly interesting because the optimal ordering decision needs to balance the inventory and purchase costs, as well as the costs for earlier and later periods. The latter cost trade-off is present only in inventory systems with three or more supply modes. Therefore, the result not only offers guidelines for the operation of the concerned inventory systems, but also provides valuable insight into the complex cost trade-offs when more supply modes are available. We assume that the difference between the lead times is one period, and the inventory holding and shortage costs are linear. We analyze two cases and obtain the structure of the optimal ordering policy. Moreover, in the first case, explicit formulas are derived to calculate the optimal order-up-to levels. In the second case, although the optimal order-up-to levels are functions of the initial inventory state and are not obtained in closed form, their properties are discussed. We also develop heuristic ordering policies based on the news-vendor model. Our numerical experiments suggest that the heuristic policies perform reasonably well. © 1996 John Wiley & Sons, Inc. 相似文献
164.
In this article, a geometric process model is introduced for the analysis of a two-component series system with one repairman. For each component, the successive operating times form a decreasing geometric process with exponential distribution, whereas the consecutive repair times constitute an increasing geometric process with exponential distribution, but the replacement times form a renewal process with exponential distribution. By introducing two supplementary variables, a set of partial differential equations is derived. These equations can be solved analytically or numerically. Further, the availability and the rate of occurrence of failure of the system are also determined. © 1996 John Wiley & Sons, Inc. 相似文献
165.
P. Patrick Wang 《海军后勤学研究》1993,40(3):345-360
In this article we consider a single-server system whose customers arrive by appointments only. Both static and dynamic scheduling problems are studied. In static scheduling problems, one considers scheduling a finite number of customer arrivals, assuming there is no scheduled customer arrival to the system. In dynamic scheduling problems, one considers scheduling one customer arrival only, assuming that there are a number of scheduled customers already. The expected delay time is recursively computed in terms of customer interarrival times for both cases. The objective is to minimize the weighted customer delay time and the server completion time. The problem is formulated as a set of nonlinear equations. Various numerical examples are illustrated. © 1993 John Wiley & Sons, Inc. 相似文献
166.
167.
张金荣 《军队政工理论研究》2006,7(5):11-13
科学发展观是加强和改进政治工作的重要指导方针。更加有力、更加扎实、更加富有成效地开展政治工作,必须牢固确立以科学发展观为指导的理念,切实理清工作思路,努力掌握科学方法,不断提高能力素质。 相似文献
168.
社会主义荣辱观的提出,为构建和谐社会、推进思想道德建设提供了根本遵循,明确了当代中国最基本价值导向和行为准则。我们要紧密结合部队建设实际,增强践行“八荣八耻”的自觉性和坚定性,努力做社会主义荣辱观的模范实践者。 相似文献
169.
张本正 《军队政工理论研究》2006,7(5):82-84
推进军事学研究生教育科学发展,必须贯彻落实科学发展观,坚持以人为本,树立发展的质量观、特色的质量观、全面的质量观;坚持协调发展,统筹数量规模与质量效益的关系、学术型标准与应用型标准的关系、共性要求与个性发展的关系;坚持固本强基,加强学科专业建设、导师队伍建设、政策制度建设,为研究生教育的可持续发展提供强大动力。 相似文献
170.
Demand for some items can depend on the inventory level on display, a phenomenon often exploited by marketing researchers and practitioners. The implications of this phenomenon have received scant attention in the context of periodic-review inventory control models. We develop an approach to model periodic-review production/inventory problems where the demand in any period depends randomly, in a very general form, on the starting inventory level. We first obtain a complete analytical solution for a single-period model. We then investigate two multiperiod models, one with lost sales and the other with backlogging, whose optimal policies turn out to be myopic. Some extensions are also discussed. © 1994 John Wiley & Sons, Inc. 相似文献