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731.
针对要地防空指挥控制系统的组成、结构和功能,通过双层图对作战体系结构进行建模,提出体现作战体系作战业务流程、信息连通性的双层信息链搜索和解析方法,实现了将信息链与作战体系能力分析的有机关联。仿真验证表明,该方法有效地体现了在作战体系能力分析中,各类型作战实体的协作性和连通性,提高了作战体系作战能力与体系结构的融合能力,利于作战体系的作战效能评估。  相似文献   
732.
As the USA continues to decline both in relative and absolute terms, the global order emerges where no center of power exists. This creates a complicated and instable geopolitical situation where small states could act behind the back of the great powers. The relationship between Turkmenistan and Ukraine is the example of this sort of relationship. Whereas Ukraine wants to get cheap gas, Turkmenistan wants to find the way to sell its gas to the West. It looks as though both countries pay little attention to Russian objection and act without direct help from either the USA or other great powers.  相似文献   
733.
《防务技术》2014,10(2):124-130
A method of augmenting an airborne vehicle for short-period dynamics and stability by passive means is presented in this study. A trajectory-phase disturbance rejection capability is achieved for an unguided fin-stabilized vehicle by flexible mounting of the fins to the vehicle body. The deflecting fins lag the body oscillation such that the harmonic oscillation can be quickly dampened. The amount of fin deflection may be chosen by a hinge-line location; among other things, the vehicle damping behaviour is largely determined by this choice. Linear theory is applied and 6-DOF simulations are carried out to demonstrate the approach suitability for the task.  相似文献   
734.
光子晶体光纤的空气孔膨胀和拉锥技术是一种有效的改变光纤结构参数的技术手段.空气孔膨胀可以改变空气孔的填充比例,即改变空气孔直径和孔间距的大小,光纤拉锥可在保持空气孔直径和孔间距比例不变的情况下改变纤芯的大小.光子晶体光纤结构参数的可控性改变可实现一些特殊光子晶体光纤器件的制作,对进一步实现和挖掘光子晶体光纤的潜在应用价...  相似文献   
735.
基于高温超导材料结构的准二维性,建立了高温超导的层状理论,得到了高温超导材料的临界温度Tc与Cu-O面数l间的关系,指出高物质密度N_i~0和高电子密度N_e~0的超导材料可能有更高的Tc。  相似文献   
736.
Abstract

This article re-examines part of the literature on Britain’s role in the December 1979 to March 1980 Zimbabwe/Rhodesia ceasefire. The ceasefire ushered in an era of peace after a protracted internal war and it was an integral part of the transition from colonial white minority rule, towards black majority independence. Scholars present Britain’s success in brokering and monitoring the Zimbabwe/Rhodesia ceasefire as the result of its judicious and accordant management of the road to peace. However, this article argues that in fact deep internal divisions plagued the British managers of the ceasefire. Internal divisions centred on authority struggles between diplomats and military actors, conflicting personalities, discordant approaches to and goals in the ceasefire, and inter-institutional rivalry between the Foreign Office and Ministry of Defence. The article concludes that Britain only managed the ceasefire effectively because its military’s independence, political nous, and competence ultimately prevailed over the injudicious views and machinations of diplomats.  相似文献   
737.
燃气发生器是超燃冲压发动机地面试验系统中的关键设备,为提高系统安全性和经济性设计了空气/煤油/水燃气发生器,在富燃状态下进行了一系列点火试验,试验结果表明:该型燃气发生器,实现可靠点火的余氧系数下限为0.51;水的加入使得化学反应速率和火焰传播速度降低,燃气发生器点火和火焰稳定困难,提高余氧系数可以提高点火可靠性。同时水的加入容易引起燃烧不稳定,通过提高余氧系数可消除低频不稳定燃烧。  相似文献   
738.
The defense establishments of all major powers are changing to reflect changes in the foundations of national security strategy and resource allocation. The authors believe economists should play an active role in formulating these changes and offer an orientation to the U.S. debate, presenting three major alternatives: the “Base Force” (Bush Administration), Mr. Aspin's Force “C,” and the “Low” Alternative (Prof. Kaufmann and Dr. Steinbruner). These alternatives are compared using first‐order measures of capabilities, budgets and risk. Budgetary estimates are based on newly‐developed analytical tools.  相似文献   
739.
We examine the theoretical outcomes of disarmament on economic activity in a two‐sector model of endogenous equilibrium unemployment rate. Three main shocks are analyzed: Exogenous cutbacks in military spending on the capital good and employment, and a reduction in public sector debt. The first shock is contractionary for equilibrium employment if the capital‐goods producing sector is relatively labour‐intensive but expansionary under the alternative factor intensity assumption. The second shock is contractionary for employment under either relative factor intensity assumption. If Ricardian equivalence fails, a reduction in public sector debt is likely to expand long‐term employment (JEL E24).  相似文献   
740.
This paper models the determination of the defence industrial base – the number of different military systems a country decides to maintain. High R&D costs means that few countries can afford to produce major weapons systems and the producers also import systems. Non‐producers rely on imports and we assume their demand is driven by regional arms races. Military capability is determined by the number of systems and the quantity and quality of each. We examine how the defence industrial base is influenced by military expenditures, R&D costs, export controls, the nature of regional arms races and a variety of other factors.  相似文献   
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