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841.
舰艇火控系统特点分析   总被引:5,自引:0,他引:5  
本文研究了舰艇火控系统公共特点,并分别对舰炮、导弹、鱼雷、深水炸弹火控系统进行了特点分析,最后引出了舰艇火控系统特点分析的两点结论。  相似文献   
842.
This article aims to encourage the fostering of more systems thinking, and its greater exploitation, within the domain of contemporary intelligence. With particular focus on “micro systems thinking” and with reference to key intelligence processes, such as intelligence analysis, the utility of many systems dynamics within the intelligence context seeks to be further revealed. Through their greater collective harnessing, including up to “System of Systems” (“SoS”) dynamics, and promoting all that they can offer, more sophisticated overarching operational-to-strategic/policy “ends,” notably that of “defence-in-depth,” can be viably further advanced in a sustainable manner into the future. Arguably, a much-needed transformative impact on contemporary intelligence can also be increasingly realised through comprehensively engaging in and with more systems and SoS thinking. Aiding civil protection tasks, crisis management, emergency planners, and civil contingency practitioners likewise gain.  相似文献   
843.
针对脉冲激光雷达系统,通过对激光脉冲重叠方式的分析,确定了采用\"五点式\"重叠方式进行扫描。针对这种扫描方式,分析了方位和俯仰两个方向的扫描光束角步长,确定了对于确定探测空域的最短扫描时间,推导了反射镜在方位和俯仰两个方向的扫描速度以及两者之间的定量关系,给出了脉冲激光雷达扫描器方位扫描速度和俯仰扫描速度设计的理论依据。最后分析了激光器和机械扫描系统所引起的系统误差,并给出了解决方法。  相似文献   
844.
《防务技术》2025,43(1):44-59
The multi-target assignment(MTA)problem,a crucial challenge in command control,mission planning,and a fundamental research focus in military operations,has garnered significant attention over the years.Extensively studied across various domains such as land,sea,air,space,and electronics,the MTA problem has led to the emergence of numerous models and algorithms.To delve deeper into this field,this paper starts by conducting a bibliometric analysis on 463 Scopus database papers using CiteSpace software.The analysis includes examining keyword clustering,co-occurrence,and burst,with visual representations of the results.Following this,the paper provides an overview of current classification and modeling techniques for addressing the MTA problem,distinguishing between static multi-target assignment(SMTA)and dynamic multi-target assignment(DMTA).Subsequently,existing solution al-gorithms for the MTA problem are reviewed,generally falling into three categories:exact algorithms,heuristic algorithms,and machine learning algorithms.Finally,a development framework is proposed based on the\"HIGH\"model(high-speed,integrated,great,harmonious)to guide future research and intelligent weapon system development concerning the MTA problem.This framework emphasizes application scenarios,modeling mechanisms,solution algorithms,and system efficiency to offer a roadmap for future exploration in this area.  相似文献   
845.
    
This paper proposes a simple game-theoretic framework for analyzing the relationship between the government, industry and indigenous community, especially in the context of mounting violence surrounding displacement of indigenous communities by governments for the purposes of commercial use of their habitat. It specifically takes into account the possibility of alleged ‘nexus’ between the government and the industry and explores its implications on the level of allocation and utilities of the players. We find that the bias in allocation that occurs when the government and the industry enter a ‘nexus’ can be rectified when there is resistance from the indigenous groups. Moreover, rebellion is a dominant strategy of the indigenous community, irrespective of whether there is ‘nexus’ or not, and being in ‘nexus’ with the government is a best response for the industry. The unique SPNE occurs when there is ‘nexus’ between the industry and the government and resistance by the indigenous groups, corroborating the widespread allegations of ‘nexus’ and evidence of resistance worldwide. We also explore a few extensions of the basic model and present some narrative evidence in support of the theoretical model.  相似文献   
846.
    
In reliability engineering, the concept of minimal repair describes that the repair brings the failed unit (eg, system or component) to the situation which is same as it was just before the failure. With the help of the well‐known Gamma‐Poisson relationship, this paper investigates optimal allocation strategies of minimal repairs for parallel and series systems through implementing stochastic comparisons of various allocation policies in terms of the hazard rate, the reversed hazard rate, and the likelihood ratio orderings. Numerical examples are presented to illustrate these findings as well. These results not only strengthen and generalize some known ones in the seminal work of Shaked and Shanthikumar, but also solve the open problems proposed by Chahkandi et al.'s study and Arriaza et al.'s study.  相似文献   
847.
    
As a complex system with multiple components usually deteriorates with age, preventive maintenance (PM) is often performed to keep the system functioning in a good state to prolong its effective age. In this study, a nonhomogeneous Poisson process with a power law failure intensity is used to describe the deterioration of a repairable system, and the optimal nonperiodic PM schedule can be determined to minimize the expected total cost per unit time. However, since the determination of such optimal PM policies may involve numerous uncertainties, which typically make the analyses difficult to perform because of the scarcity of data, a Bayesian decision model, which utilizes all available information effectively, is also proposed for determining the optimal PM strategies. A numerical example with a real failure data set is used to illustrate the effectiveness of the proposed approach. The results show that the optimal schedules derived by Bayesian approach are relatively more conservative than that for non‐Bayesian approach because of the uncertainty of the intensity function, and if the intensity function are updated using the collected data set, which indicates more severe deterioration than the prior belief, replacing the entire system instead of frequent PM activities before serious deterioration is suggested. © 2010 Wiley Periodicals, Inc. Naval Research Logistics, 2010  相似文献   
848.
藏区地基换填戈壁土处理的经济适用性评价   总被引:1,自引:0,他引:1  
藏区地基处理中如果能采用戈壁土作为换填材料,可以较好的解决该地区地基加固费用高的问题。结合某新建工程,对换填戈壁土方法进行经济适用性评价,结果表明该方法经济合理,可以推广应用。  相似文献   
849.
根据现代海战的要求,对舰炮武器系统维修性试验的必要性和重要性作出分析阐述;依据舰炮武器系统的组成特点,科学地制定了维修性试验的基本程序和试验项目;给出舰炮武器系统维修性试验具体试验方案.  相似文献   
850.
针对当前威胁估计中存在的问题,提出了基于贝叶斯网络的空中目标威胁估计方法。文章从威胁估计的概念出发,构建了基于贝叶斯网络的威胁估计功能框架,在对输入的防空作战事件进行分类定义的基础上,给出了事件关联在贝叶斯网络中的实现方法,同时对模型的建立步骤进行了说明。文中提出的威胁估计方法在融合了目标威胁先验信息的基础上,通过战场观测到的不确定信息进行推理,其结果具有很强的可信性,相应的建模思路可为威胁估计系统的构建提供有益的参考。文章的最后以一个示例说明了方法的有效性。  相似文献   
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