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1.
总结和推广了非线性动态系统渐近滑态(ASM)控制方法的若干理论成果。在相当一般的假设条件下,我们指出了可以采用连续(乃至光滑)的控制方案,将系统的状态驱往给定的滑动流形上。此外,我们还引入了基于Hamilton-Jacobi方程的理论方法,统一了先前得到的关于闭环系统鲁棒性分析的结果。最后我们列举了一些应用例子和研究建议。  相似文献   
2.
烟幕干扰技术综述   总被引:4,自引:0,他引:4  
现代战争中,面对我国重要经济目标数量多、防护力量和资源有限的现状,选择各种高效费比的防护措施才能适应我国国情。烟幕正是一种成本低、效果明显、操作简单的干扰手段。阐述了烟幕的产生、干扰原理,重点介绍了各波段的烟幕干扰材料、常用的烟幕器材及烟幕的具体应用,对重要经济目标防护工作的实际操作具有一定借鉴意义。  相似文献   
3.
This article presents two meta‐ranking models that minimize or nearly minimize violations of past game results while predicting future game winners as well as or better than leading current systems—a combination never before offered for college football. Key to both is the development and integration of a highly predictive ensemble probability model generated from the analysis of 36 existing college football ranking systems. This ensemble model is used to determine a target ranking that is used in two versions of a hierarchical multiobjective mixed binary integer linear program (MOMBILP). When compared to 75 other systems out‐of‐sample, one MOMBILP was the leading predictive system while getting within 0.64% of the retrodictive optimum; the other MOMBILP minimized violations while achieving a prediction total that was 2.55% lower than the best mark. For bowls, prediction sums were not statistically significantly different from the leading value, while achieving optimum or near‐optimum violation counts. This performance points to these models as potential means of reconciling the contrasting perspectives of predictiveness versus the matching of past performance when it comes to ranking fairness in college football. © 2013 Wiley Periodicals, Inc. Naval Research Logistics 61: 17–33, 2014  相似文献   
4.
The laser technology has made remarkable progress over the past couple of decades.It is being widely employed in diverse domains,such as holography,space sciences,spectroscopy,medical sciences,micro and power electronics,industrial engineering,and most distinctively,as directed energy military weapons.Owing to their active transmissions,laser systems are similar to microwave radars to some extent;however,unlike conventional radars,the laser operates at very high frequencies thus making it a potent enabler of narrow-beam and high energy aerial deployments,both in offensive and defensive roles.In modern avionics systems,laser target indicators and beam riders are the most common devices that are used to direct the Laser Guided Weapons(LGW)accurately to the ground targets.Additionally,compact size and outstanding angular resolution of laser-based systems motivate their use for drones and unmanned aerial applications.Moreover,the narrow-beam divergence of laser emissions offers a low probability of intercept,making it a suitable contender for secure transmissions and safety-critical operations.Furthermore,the developments in space sciences and laser technology have given syner-gistic potential outcomes to use laser systems in space operations.This paper comprehensively reviews laser applications and projects for strategic defense actions on the ground or in space.Additionally,a detailed analysis has been done on recent advancements of the laser technology for target indicators and range-finders.It also reviews the advancements in the field of laser communications for surveillance,its earlier state of the art,and ongoing scientific research and ad-vancements in the domain of high energy directed laser weapons that have revolutionized the evolving military battlefield.Besides offering a comprehensive taxonomy,the paper also critically analyzes some of the recent contributions in the associated domains.  相似文献   
5.
区块链技术来源于数字货币,是一种具有去中心化、自信任、公开透明、数据不可篡改、隐私保护等特点的分布式数据账本。在国防与军队建设领域,区块链技术由于其技术理念的先进性而具有相当广阔的应用前景,它将导致思维理念、作战方式与管理方式的全方位创新,但是区块链技术在应用过程中,也存在一定缺陷。由于具备高传输速率、低网络时延、超强连接能力以及更灵活的业务部署能力,5G技术成为弥补区块链技术不足的首选。本文首先分别介绍了5G技术和区块链技术的主要军事应用前景和存在的困难;其次,分析了5G与区块链之间的互补影响及两种技术融合发展的可能性;最后,从军事供应链、智慧军营和无人作战平台等方面深入探讨了5G与区块链典型军事应用中可能面临的挑战。  相似文献   
6.
介绍了虚拟现实的概念、虚拟现实的发展应用和相关技术,重点介绍美国军方应用虚拟现实的情况。  相似文献   
7.
在众多安全保卫工作中,无线通信联络是确保警卫指挥有条不紊的重要环节。结合上海警卫部队特点及警卫工作实际。对世博安保警卫工作无线通信指挥平台的构建与应用,进行了回顾和总结。同时,也对警卫工作信息化建设进一步发展的具体思路,提出一些新的观点和理念。  相似文献   
8.
We study a generalization of the weighted set covering problem where every element needs to be covered multiple times. When no set contains more than two elements, we can solve the problem in polynomial time by solving a corresponding weighted perfect b‐matching problem. In general, we may use a polynomial‐time greedy heuristic similar to the one for the classical weighted set covering problem studied by D.S. Johnson [Approximation algorithms for combinatorial problems, J Comput Syst Sci 9 (1974), 256–278], L. Lovasz [On the ratio of optimal integral and fractional covers, Discrete Math 13 (1975), 383–390], and V. Chvatal [A greedy heuristic for the set‐covering problem, Math Oper Res 4(3) (1979), 233–235] to get an approximate solution for the problem. We find a worst‐case bound for the heuristic similar to that for the classical problem. In addition, we introduce a general type of probability distribution for the population of the problem instances and prove that the greedy heuristic is asymptotically optimal for instances drawn from such a distribution. We also conduct computational studies to compare solutions resulting from running the heuristic and from running the commercial integer programming solver CPLEX on problem instances drawn from a more specific type of distribution. The results clearly exemplify benefits of using the greedy heuristic when problem instances are large. © 2003 Wiley Periodicals, Inc. Naval Research Logistics, 2005  相似文献   
9.
We formulate and solve a discrete‐time path‐optimization problem where a single searcher, operating in a discretized three‐dimensional airspace, looks for a moving target in a finite set of cells. The searcher is constrained by maximum limits on the consumption of one or more resources such as time, fuel, and risk along any path. We develop a specialized branch‐and‐bound algorithm for this problem that uses several network reduction procedures as well as a new bounding technique based on Lagrangian relaxation and network expansion. The resulting algorithm outperforms a state‐of‐the‐art algorithm for solving time‐constrained problems and also is the first algorithm to solve multi‐constrained problems. © 2010 Wiley Periodicals, Inc. Naval Research Logistics, 2010  相似文献   
10.
微胶囊技术简介   总被引:3,自引:0,他引:3  
微胶囊技术能够使物质产生物态变化,实现物质的固化,在医药、农药、食品、饲料、涂料、油墨、黏合剂、洗涤剂、感光材料、纺织等行业,都得到了广泛的应用。介绍了微胶囊技术的发展史,微胶囊的组成与制备方法,微胶囊的性质及应用.  相似文献   
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