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61.
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   
62.
While there has been significant previous literature on inventory transshipment, most research has focused on the dealers' demand filling decision (when to fill transshipment requests from other dealers), ignoring the requesting decision (when to send transshipment requests to other dealers). In this paper we develop optimal inventory transshipment policies that incorporate both types of decisions. We consider a decentralized system in which the dealers are independent of the manufacturer and of each other. We first study a network consisting of a very large number of dealers. We prove that the optimal inventory and transshipment decisions for an individual dealer are controlled by threshold rationing and requesting levels. Then, in order to study the impact of transshipment among independent dealers in a smaller dealer network, we consider a decentralized two‐dealer network and use a game theoretic approach to characterize the equilibrium inventory strategies of the individual dealers. An extensive numerical study highlights the impact of the requesting decision on the dealers' equilibrium behavior in a decentralized setting. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2006  相似文献   
63.
针对新型驱护舰编队舰空导弹防御体系射击效能评估这一难题,对其射击效能准则进行了确立,提出了基于排队论的射击效能评估模型,对体系射击效能进行仿真计算,总结出能对系统射击效能做出准确评估的方法,并利用实例对模型进行了验证。  相似文献   
64.
反舰导弹是当今舰艇及编队面临的主要威胁。为评估反舰导弹攻防能力,以目前世界上防御能力最强的美国航母战斗群为背景,研究采用分层火力配置的航母舰队防御体系对付反舰导弹的有效性。首先分析反舰导弹飞行高度、雷达散射截面及综合效应对防御系统中雷达探测能力的影响,之后应用简化公式,对各类典型舰载对空防御武器的最大拦截距离、拦截次数和拦截效率进行量化分析,对防御反舰导弹能力做出评估。  相似文献   
65.
The (standard) randomization method is an attractive alternative for the transient analysis of continuous time Markov models. The main advantages of the method are numerical stability, well‐controlled computation error, and ability to specify the computation error in advance. However, the fact that the method can be computationally very expensive limits its applicability. In this paper, we develop a new method called split regenerative randomization, which, having the same good properties as standard randomization, can be significantly more efficient. The method covers reliability‐like models with a particular but quite general structure and requires the selection of a subset of states and a regenerative state satisfying some conditions. For a class of continuous time Markov models, model class C2, including typical failure/repair reliability‐like models with exponential failure and repair time distributions and deferred repair, natural selections are available for both the subset of states and the regenerative state and, for those natural selections, theoretical results are available assessing the efficiency of the method in terms of “visible” model characteristics. Those results can be used to anticipate when the method can be expected to be competitive. We illustrate the application of the method using a large class C2 model and show that for models in that class the method can indeed be significantly more efficient than previously available randomization‐based methods. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2006  相似文献   
66.
After only ten years in existence, the African Union (AU) has already made its mark on the landscape of peace and security in Africa. This paper seeks to explore the relationship between the AU's leading collaborative interstate security policy, the African Peace and Security Architecture (APSA), and sustainable peace in the Horn of Africa. It examines four countries – Djibouti, Eritrea, Ethiopia, and Kenya – and how engaging with the APSA through early warning systems can contribute to developing the elements necessary for sustainable peace, namely regional stability, conflict management, and good governance.  相似文献   
67.
吴磊  王干  李涛 《国防科技》2013,(6):37-40
由生物附着引起的船舶航速下降、过量耗费燃料(温室气体排放)及过高的船舶维修保养费用及船舶腐蚀等一系列问题,使得相关部门不得不耗费巨资来解决这一问题,同时也引起了生物学、流体力学、材料学及工程学等多个学科的专家们的共同关注。文章主要根据现阶段研究进展介绍了生物污损的过程及附着生物的分类.最后概述了防除船舶附着生物方法,并探讨了采用宏基因组学方法来尝试解决生物附着问题的可能性。  相似文献   
68.
The current approach to countering the threat of improvised explosive devices (IEDs) in Afghanistan has met with limited success. The relative lack of success may be in part because the current approach is not holistic and discounts the social systems that foster the IEDs. Insurgents are using IEDs as a tool to further their strategic aims, but the coalition and to a lesser extent the Government of the Islamic Republic of Afghanistan (GIRoA) are attacking the IEDs as if they are an end in and of themselves. Combining network disruption with information change maximizes the opportunities for mitigating the IED threat. More specifically, to mitigate the IED threat requires disrupting the social and economic systems associated with IEDs, and at the same time providing alternative economic opportunities and improving rule of law and governance at the local level. In other words, counter-IED (C-IED) must be Counter-Insurgency (COIN) centric to be successful. This paper reviews the current state of C-IED efforts, identifies five main problems with the current approach, and suggests changes to reduce or mitigate the IED threat in Afghanistan.  相似文献   
69.
目标毁伤效果评估作为目标保障的一项重要内容,对精确打击作战情报保障起到了核心作用,是现代精确打击体系的一个重要环节和关键步骤。文章从评估方法、评估模型和评估系统三个方面入手,梳理了国内外目标毁伤效果评估技术的最新研究进展,并对目前各类评估方法、模型及系统的优缺点分别进行了评述。最后,指出了该领域今后的研究方向。  相似文献   
70.
在剖析海军装备体系与体系技术概念的基础上,分析了海军装备体系技术的特点与作用,提出了海军装备体系技术的基本构成,为海军装备体系技术的应用研究提供理论指导。  相似文献   
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