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261.
高频地波雷达作战效能评估分析方法   总被引:1,自引:0,他引:1  
根据高频地波雷达的特点和作战任务,采用层次分析法,从探测能力、情报质量和生存能力三个指标层给出了高频地波雷达作战效能评估的层次结构体系,并确定了各效能指标及相对权重的计算方法,最后得出了高频地波雷达作战效能评估的定量分析方法,解决了雷达系统作为非直接杀伤性武器而无法评价其在作战背景下的作战效能的问题,为该雷达的作战使用提供了辅助决策的依据.  相似文献   
262.
本文通过对石河子大学公体教学改革实施情况的调查研究,进一步论证了公共体育教学改革采用兴趣选项模式的可行性。同时,经过调查对照参考北大模式制定的石大公体教改乒乓球教学大纲进行了论证和分析,提出了一些建议。  相似文献   
263.
卫星军事应用系统作战效能评估的网络层次分析法研究   总被引:1,自引:0,他引:1  
根据卫星军事应用系统的特点研究了基于网络层次分析法的效能评估方法.确立了效能评价的准则,给出了影响其作战效能的指标集,建立了网络层次分析法控制层和网络层模型,并且利用计算极限超矩阵的方法对单个准则下各方案的作战效能进行排序.最后,通过对单个准则下的排序向量进行加权求和获得卫星军事应用系统作战效能的排序向量.  相似文献   
264.
提出了直接根据单指标相对隶属度的模糊评价矩阵,构造层次分析法中的判断矩阵用以确定各评价指标权重的方法,给出了用遗传算法检验和修正判断矩阵的一致性和计算判断矩阵各要素的权重的模糊综合评价模型,对潜射反舰导弹作战效能进行了综合评估和排序.实例表明,该方法简便通用,计算结果较为客观和稳定.  相似文献   
265.
The frequent occurrence of safety accidents during the calendering process is caused by the flammable and explosive properties of composite modified double-base (CMDB) propellant. Optimization of process parameters with the aid of fluid simulation technology could effectively ensure the safety of the calendering process. To improve the accuracy of the simulation results, material parameters and model structure were corrected based on actual conditions, and adaptive grid technology was applied in the local mesh refinement. In addition, the rheological behavior, motion trajectories and heat transfer mechanisms of CMDB propellant slurry were studied with different gaps, rotational rates and temperatures of two rollers. The results indicated that the refined mesh could significantly improve the contour clarity of boundaries and simulate the characteristics of CMDB propellant slurry reflux movement caused by the convergent flow near the outlet. Compared with the gap, the increased rotational rate of roller could promote the reflux movement and intensify the shear flow of slurry inside the flow region by viscous shear dragging. Meanwhile, under the synergistic effect of contact heat transfer as well as convective heat exchange, heat accumulated near the outlet and diffused along the reflux movement, which led to the countercurrent heat dissipation behavior of CMDB propellant slurry. The plasticizing mechanism of slurry and the safety of calendering under different conditions were explored, which provided theoretical guidance and reference data for the optimization of calendering process conditions. Based on the simulation results, the safety of the CMDB propellant calendering process could be significantly improved with a few tests conducted during a short research and development cycle.  相似文献   
266.
信息时代 ,个人上网机的信息保护越来越受到社会的重视 ,个人防火墙就应运而生。首先简单介绍个人防火墙的原理和功能 ,在特殊IP的过滤和端口、漏洞和进程防护几个方面分析了当前一些典型的个人防火墙产品存在的缺点 ,提出了EPFW的概念 ,然后阐述了EPFW对个人防火墙的IP过滤、端口防护、漏洞防护、病毒防护和进程防护进行增强的设计问题、技术难点以及解决方法。这些都说明对于PC机信息保护而言 ,EPFW是一个可行的合理的解决方案。  相似文献   
267.
针对空中骨干Mesh网络资源有限、计算能力相对不足的特点以及传统简单机会路由(Simple Opportunistic Adaptive Routing,SOAR)路由算法未充分考虑负载均衡与不同业务服务质量(Quality of Service,Qo S)保障需求差异性的问题,提出一种支持业务区分的改进型SOAR路由算法。该算法在考虑链路拥塞控制和负载均衡的基础上,定义综合预期传输次数来描述链路的综合状态,有效降低网络拥塞概率;同时根据传输业务类型的不同,设计一种基于层次分析法的路由选择策略,实现路径选择与业务类型的动态匹配。仿真结果表明,在重负载条件下,改进型SOAR路由算法相比传统SOAR路由算法其时延、吞吐量和吞吐率性能明显提升。当网络中存在不同类型业务时,改进型SOAR路由算法能够根据业务Qo S保障需求的差异性自适应选择最佳传输路径。  相似文献   
268.
红外成像制导系统是一个技术要求高的复杂大系统。介绍了导弹红外制导控制仿真系统的组成、功能及仿真过程,同时阐明了成像制导半实物仿真系统设计中涉及到的图像目标模拟、图像导引头的介入方式以及制导部件仿真测试和图像生成等问题的解决和设计方法。  相似文献   
269.
When a control chart signals an out‐of‐control condition for a production process, it may be desirable to “quarantine” all units produced since the last in‐control SPC sample. This paper presents an efficient procedure for variables inspection of such “SPC quarantined” product. A Bayesian sequential inspection procedure is developed which determines whether the out of control production is of acceptable quality. By inspecting the units in reverse of the order in which they were produced, the procedure is also capable of detecting the point at which the process went out of control, thus eliminating the need to inspect units produced prior to the onset of the out of control condition. Numerical examples are presented, and the performance characteristics of the procedure are demonstrated using Monte Carlo simulation. © 2001 John Wiley & Sons, Inc. Naval Research Logistics 48: 159–171, 2001  相似文献   
270.
Consider a binary, monotone system of n components. The assessment of the parameter vector, θ, of the joint distribution of the lifetimes of the components and hence of the reliability of the system is often difficult due to scarcity of data. It is therefore important to make use of all information in an efficient way. For instance, prior knowledge is often of importance and can indeed conveniently be incorporated by the Bayesian approach. It may also be important to continuously extract information from a system currently in operation. This may be useful both for decisions concerning the system in operation as well as for decisions improving the components or changing the design of similar new systems. As in Meilijson [12], life‐monitoring of some components and conditional life‐monitoring of some others is considered. In addition to data arising from this monitoring scheme, so‐called autopsy data are observed, if not censored. The probabilistic structure underlying this kind of data is described, and basic likelihood formulae are arrived at. A thorough discussion of an important aspect of this probabilistic structure, the inspection strategy, is given. Based on a version of this strategy a procedure for preventive system maintenance is developed and a detailed application to a network system presented. All the way a Bayesian approach to estimation of θ is applied. For the special case where components are conditionally independent given θ with exponentially distributed lifetimes it is shown that the weighted sum of products of generalized gamma distributions, as introduced in Gåsemyr and Natvig [7], is the conjugate prior for θ. © 2001 John Wiley & Sons, Inc. Naval Research Logistics 48: 551–577, 2001.  相似文献   
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