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201.
运用多目标决策分析原理,依据选择防御要点的基本要求,从"地位重要、地形有利、地幅适当"的角度分析了防御要点的影响因素集,运用灰色理论建立了防御要点灰色关联优选模型,达到了对防御要点进行排序和优选的目的,为指挥员实施防御作战的科学决策提供辅助依据。  相似文献   
202.
介绍了数字自动增益控制(AGC)技术在数字中频接收机中的实现方法’,提出了利用 DSP Builder模型库设计的一种实用的数字自动增益控制电路,所设计的电路在数字中频接收机系统内工作良好。该数字 AGC具有快速收敛、结构简单、性能稳定和成本低等特点。占用 Altera StratixⅡ FPGA 片上163个自适应逻辑单元(ALUTs)。  相似文献   
203.
介绍了美军移动用户目标系统MUOS(Mobile User Objective System),分析和总结了该系统下网络管理体系结构和运行机制,并就其实现中的关键技术进行了深入研究,得到了一些对我国有借鉴意义的结论。  相似文献   
204.
In this paper, we present an optimization model for coordinating inventory and transportation decisions at an outbound distribution warehouse that serves a group of customers located in a given market area. For the practical problems which motivated this paper, the warehouse is operated by a third party logistics provider. However, the models developed here may be applicable in a more general context where outbound distribution is managed by another supply chain member, e.g., a manufacturer. We consider the case where the aggregate demand of the market area is constant and known per period (e.g., per day). Under an immediate delivery policy, an outbound shipment is released each time a demand is realized (e.g., on a daily basis). On the other hand, if these shipments are consolidated over time, then larger (hence more economical) outbound freight quantities can be dispatched. In this case, the physical inventory requirements at the third party warehouse (TPW) are determined by the consolidated freight quantities. Thus, stock replenishment and outbound shipment release policies should be coordinated. By optimizing inventory and freight consolidation decisions simultaneously, we compute the parameters of an integrated inventory/outbound transportation policy. These parameters determine: (i) how often to dispatch a truck so that transportation scale economies are realized and timely delivery requirements are met, and (ii) how often, and in what quantities, the stock should be replenished at the TPW. We prove that the optimal shipment release timing policy is nonstationary, and we present algorithms for computing the policy parameters for both the uncapacitated and finite cargo capacity problems. The model presented in this study is considerably different from the existing inventory/transportation models in the literature. The classical inventory literature assumes that demands should be satisfied as they arrive so that outbound shipment costs are sunk costs, or else these costs are covered by the customer. Hence, the classical literature does not model outbound transportation costs. However, if a freight consolidation policy is in place then the outbound transportation costs can no longer be ignored in optimization. Relying on this observation, this paper models outbound transportation costs, freight consolidation decisions, and cargo capacity constraints explicitly. © 2002 Wiley Periodicals, Inc. Naval Research Logistics 49: 531–556, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/nav.10030  相似文献   
205.
The “gold‐mining” decision problem is concerned with the efficient utilization of a delicate mining equipment working in a number of different mines. Richard Bellman was the first to consider this type of a problem. The solution found by Bellman for the finite‐horizon, continuous‐time version of the problem with two mines is not overly realistic since he assumed that fractional parts of the same mining equipment could be used in different mines and this fraction could change instantaneously. In this paper, we provide some extensions to this model in order to produce more operational and realistic solutions. Our first model is concerned with developing an operational policy where the equipment may be switched from one mine to the other at most once during a finite horizon. In the next extension we incorporate a cost component in the objective function and assume that the horizon length is not fixed but it is the second decision variable. Structural properties of the optimal solutions are obtained using nonlinear programming. Each model and its solution is illustrated with a numerical example. The models developed here may have potential applications in other areas including production of items requiring the same machine or choosing a sequence of activities requiring the same resource. © 2002 Wiley Periodicals, Inc. Naval Research Logistics 49: 186–203, 2002; DOI 10.1002/nav.10008  相似文献   
206.
一种变结构导引律及其在垂直命中制导中的应用   总被引:5,自引:0,他引:5  
基于变结构控制理论 ,提出了一种垂直命中目标的导引律。该导引律在引入理想的视线角基础上 ,所设计的切换函数不仅保证脱靶量为零 ,而且能同时达到垂直命中目标的目的。数字仿真表明 ,该导引律与最优垂直命中导引律相比 ,不仅适用范围广 ,而且具有良好的鲁棒性能。  相似文献   
207.
提出一种基于分段解析模糊算法的控制器。该控制器采用分段解析函数控制规则 ,函数运算结果直接作为输出控制量 ,简化了模糊处理过程 ,且使得输出控制量参数具有自调整能力。实际应用表明 ,该模糊控制器成功地实现了火箭炮的自动操瞄控制。  相似文献   
208.
层次分析法在选择导弹发射阵地中的应用   总被引:7,自引:2,他引:5  
探讨了最优发射阵地的选择问题 ,运用层次分析法建立了评估指标的计算模型。实例计算结果表明 ,层次分析方法能够较好地解决发射阵地选择问题。  相似文献   
209.
网络化作战系统的软硬件体系   总被引:1,自引:0,他引:1  
分析了发展网络化作战系统的两个推动要素——信息技术的发展和第二代作战系统所面临的问题 ,讨论了网络作战系统的发展目标 ,提出了网络化作战系统的软硬件体系结构 ,包括硬件的三层次结构和集成化作战软件的技术方案 ,指出了实现作战系统网络化的巨大效用。  相似文献   
210.
同一地球椭球体上不同坐标系之间的坐标转换   总被引:6,自引:0,他引:6  
对于在确定的椭球体上不同位置建立的坐标系,推导了它们之间的相互转换公式。其结果具有普遍适用性,且坐标转换精度很高,具有广泛的使用价值,还可以进一步推广到空间任意点之间的坐标转换,在大地测量、定位、战术资源共享等诸多领域具有重要应用。  相似文献   
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