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111.
Hungary, a former communist state, adapted a Western-style defense planning system during the 1990s and 2000s. Although on the surface the elements of this planning system were similar to the planning programming budgeting system (PPBS) developed by the US Department of Defense, strategic guidance for defense planning has not been properly developed until recently. Thus, albeit PPBS-based defense plans were developed in the Hungarian Ministry of Defense (Hungarian MoD) regularly, they lacked both an expression of clear priorities and strategic focus. This article delineates the evolution of strategic guidance in the Hungarian MoD concentrating on current developments, and introduces the newly elaborated analytical concepts and tools, which helped to create needed strategic guidance in Hungary.  相似文献   
112.
We develop a risk‐sensitive strategic facility sizing model that makes use of readily obtainable data and addresses both capacity and responsiveness considerations. We focus on facilities whose original size cannot be adjusted over time and limits the total production equipment they can hold, which is added sequentially during a finite planning horizon. The model is parsimonious by design for compatibility with the nature of available data during early planning stages. We model demand via a univariate random variable with arbitrary forecast profiles for equipment expansion, and assume the supporting equipment additions are continuous and decided ex‐post. Under constant absolute risk aversion, operating profits are the closed‐form solution to a nontrivial linear program, thus characterizing the sizing decision via a single first‐order condition. This solution has several desired features, including the optimal facility size being eventually decreasing in forecast uncertainty and decreasing in risk aversion, as well as being generally robust to demand forecast uncertainty and cost errors. We provide structural results and show that ignoring risk considerations can lead to poor facility sizing decisions that deteriorate with increased forecast uncertainty. Existing models ignore risk considerations and assume the facility size can be adjusted over time, effectively shortening the planning horizon. Our main contribution is in addressing the problem that arises when that assumption is relaxed and, as a result, risk sensitivity and the challenges introduced by longer planning horizons and higher uncertainty must be considered. Finally, we derive accurate spreadsheet‐implementable approximations to the optimal solution, which make this model a practical capacity planning tool.© 2008 Wiley Periodicals, Inc. Naval Research Logistics, 2008  相似文献   
113.
调运问题中基于栅格模型的快速路径规划方法   总被引:2,自引:2,他引:0  
针对调运路径规划这一问题,采用栅格模型表示环境地图,通过设定路径搜索方向权重,剔除不必要的搜索区域,提高了搜索效率.仿真结果表明,该算法能有效地提高路径搜索效率,并能搜索到最优路径.  相似文献   
114.
We present a robust optimization model for production planning under the assumption that electricity supply is subject to uncertain interruptions caused by participation in interruptible load contracts (ILCs). The objective is to minimize the cost of electricity used for production while providing a robust production plan which ensures demand satisfaction under all possible interruption scenarios. The combinatorial size of the set of interruption scenarios makes this a challenging problem. Furthermore, we assume that no probabilistic information is known about the supply uncertainty: we only use the information given in the ILC to identify an uncertainty set that captures the possible scenarios. We construct a general robust framework to handle this uncertainty and present a heuristic to compute a good feasible solution of the robust model. We provide computational experiments on a real‐world example and compare the performance of an exact solver applied to the robust model with that of the heuristic procedure. Finally, we include the operational impact of interruptions such as “recovery modes” in the definition of the uncertainty set. © 2013 Wiley Periodicals, Inc. Naval Research Logistics, 2013  相似文献   
115.
By any objective measure, defense institutions in Central and Eastern Europe have all but universally been incapable of producing viable defense plans that are based on objective costing and operational planning data. This situation exists in spite the provision of considerable Western advice and assistance, let alone reporting to and receiving assessments by NATO’s International Staff under Partnership for Peace, as well as via the integrated defense planning and reporting systems. An explanation for this systematic failure across European post-Communist defense institutions can be found in the continued slow development of an over-arching policy framework which directs and approves all activities of the armed forces, as well as the de-centralization of financial decision-making down to capability providers. The essay ends with an examination of the adverse effects of the early introduction of planning programming, budgeting system (PPBS), have had on the development of effective policy and planning capabilities within these defense institutions.  相似文献   
116.
针对水面舰艇编队空中威胁扇面角的预测问题,分析了影响空中威胁扇面角大小的主要因素。以具有航路规划能力的远程反舰导弹为对象,从航空兵及远程反舰导弹的作战使用特点和装备性能限制着手,建立了计算威胁扇面角的数学模型。通过仿真分析,得出了主要参数对威胁扇面角的影响规律,为水面舰艇编队对空防御兵力的配置提供了依据。  相似文献   
117.
基于辅助制导的无人飞行器多航迹规划是现今航迹规划的主流研究方向之一。飞行器规划空间广,规划过程耗时长,如何提高航迹规划的速度是一个急待解决的问题。因此,提出了一种在预处理过程中生成的、满足战场环境和基于辅助制导无人飞行器飞行特性的有向航迹网络图。该网络图适用于基于辅助制导的无人飞行器多航迹快速规划,使用数据库存储和管理,具有整体数据结构化、易扩充、占用内存资源小、可大大缩短规划时间等优点。  相似文献   
118.
为了解决多无人机协同攻击航路规划问题,基于一种雷达威胁等效方法,以及无人机在不同姿态下雷达散射截面RCS(Radar Cross-Section)值随之改变的特性,结合多机作战战术思想,提出了一种多无人机梯次协同攻击同一目标的方法,并利用Dijkstra算法进行多无人机航路规划.仿真结果表明,该方法具有更高的应用价值.  相似文献   
119.
空域窗射击毁歼概率解析计算模型   总被引:1,自引:0,他引:1  
为提高未来空域窗射击技术对空中机动目标的毁伤概率,需要根据目标机动幅度对未来空域窗的大小进行动态设定,故提出“自适应射击窗”的概念.空域窗大小设定的依据是使毁歼概率最优.可以采用解析法来在线计算该毁歼概率值.在分析空域窗射击误差的基础上,演绎了均匀分布法与高斯和法两种毁歼概率解析计算方法的公式.以毁歼概率蒙特卡罗法仿真数据为基准值,对两种解析法的计算精度进行了对比分析.仿真结果表明,高斯和法的计算精度显著优于均匀分布法,且满足实时计算要求,适于在线评估空域窗的射击效能.  相似文献   
120.
针对反导预警作战过程中远程预警相控阵雷达(early-warning radar,EWR)和多功能地基相控阵雷达(ground-based radar,GBR)探测跟踪弹道导弹的交接班问题,提出了一种可行的雷达交接班时机选择方法.该方法通过卡尔曼滤波对弹道目标进行滤波定轨,基于目标瞬时运动状态估算目标剩余飞行距离,并依据GBR对目标的探测定位精度(geometrical dilution of precision,GDOP)进行接班时机优选,以支持反导预警作战雷达交接班决策.最后,通过一个实例验证了该方法的可行性和有效性.  相似文献   
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