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排序方式: 共有277条查询结果,搜索用时 15 毫秒
271.
本文提出了运用粒子群优化算法来对飞机低空突防进行航迹规划的方法。首先,说明了飞机突防需要满足的物理限制和战术要求。其次,根据低空突防航迹规划约束多,计算复杂的特点引入粒子群优化算法,并且对其进行简要的介绍。应用粒子群优化算法对低空突防战术进行航迹规划。最后实验结果表明,该方法能够对飞机低空突防过程规划出可行的飞行航迹。 相似文献
272.
丁红 《兵团教育学院学报》2011,21(4):23-29
作为传统媒体之一的报纸媒体,一直承担着信息传播的重要任务,在社会生活中起着重要作用。面临新媒体高速崛起,多媒体的日渐融合这样的环境,也仍然不能忽视报纸媒体的影响力。但是,在高速发展的信息社会中,报纸媒体的创意与策划显得越来越重要。 相似文献
273.
We consider a class of facility location problems with a time dimension, which requires assigning every customer to a supply facility in each of a finite number of periods. Each facility must meet all assigned customer demand in every period at a minimum cost via its production and inventory decisions. We provide exact branch‐and‐price algorithms for this class of problems and several important variants. The corresponding pricing problem takes the form of an interesting class of production planning and order selection problems. This problem class requires selecting a set of orders that maximizes profit, defined as the revenue from selected orders minus production‐planning‐related costs incurred in fulfilling the selected orders. We provide polynomial‐time dynamic programming algorithms for this class of pricing problems, as well as for generalizations thereof. Computational testing indicates the advantage of our branch‐and‐price algorithm over various approaches that use commercial software packages. These tests also highlight the significant cost savings possible from integrating location with production and inventory decisions and demonstrate that the problem is rather insensitive to forecast errors associated with the demand streams. © 2011 Wiley Periodicals, Inc. Naval Research Logistics, 2011 相似文献
274.
从科学发展观的基本内涵出发,针对基层部队建设中存在的普遍问题,从全面建设、统筹规划、保持创新三个方面进行了论证,回答了科学发展观是指导部队基层建设的灵魂这个重大问题。 相似文献
275.
O. Zeynep Akşin 《海军后勤学研究》2007,54(2):221-235
This paper derives optimal policies for when to hire, train, and lay off employees in service organizations when worker productivity appreciates deterministically or stochastically under constant, monotonic, and cyclic service demand. The model, an extension of the machine replacement problem from the engineering economy literature, uses infinite horizon linear programming to produce optimal personnel planning strategies and dual prices that characterize the workforce's economic value. The effect of employee attrition is also considered. In its valuation of human assets, unlike pure accounting approaches that only try to measure, this paper proposes an approach to capture the interaction between firm decisions pertaining to human resources and human resource value. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2007 相似文献
276.
对敌防空压制(suppression of enemy air defenses, SEAD)场景是多无人机协同的典型应用,针对该场景特点,在任务规划问题基础上将各类型无人机数量也作为决策变量,充分表征目标、任务和无人机的多种约束,建立异构无人机编队路径问题模型。设计了双层联合优化方法求解该模型:上层设计了任务衔接参数指标,精确评估各类型无人机需求,指导无人机配置调整;下层设计了改进遗传算法,高效处理多类型约束并能结合无人机数量变化对任务方案进行精细调整;双层相互协调获得满足需求的无人机配置和执行方案。仿真结果表明,该方法可以在避免遍历无人机配置组合的前提下获得合理的无人机配置方案和高效可行的执行方案。 相似文献
277.
Zsolt Lazar 《Defense & Security Analysis》2019,35(3):283-307
The Soviet-led Council for Mutual Economic Assistance member, Central European countries found themselves in a difficult political and economic situation after the collapse of the Soviet Union. Three post-Eastern Bloc countries formed the Visegrad Group to strengthen their ties to the West, but the need for foreign investment, job creation and technology transfer was urgent.
This is when military modernisation also came into the picture and the counter-trade—as known as offset—as a tool to help these economies. A trade practice which was meant to energise these economies via defence acquisitions linked economic programmes.
Two Visegrad Group member countries, Hungary and the Czech Republic decided to sign offset agreement with the defence firm SAAB to license Gripen fighter aircrafts. This study intends to analyse if these deals were able to help governments to reach their objectives or the two countries were unable to take advantage of the offset programmes. 相似文献