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71.
平流层长航时气球上升过程超冷现象影响因素分析   总被引:2,自引:2,他引:0       下载免费PDF全文
平流层长航时气球超冷现象是指内部浮升气体温度低于外界大气温度,超冷会引起浮力损失进而阻碍气球上升过程。建立了长航时气球辐射、对流等热模型和上升过程动力学模型,仿真分析了初始净浮力、蒙皮热物性参数、放飞时间和放飞日期等因素对超冷现象的影响规律。研究结果表明,上升过程内外温差随初始净浮力增大而增大且变化显著,可见光吸收率和红外吸收率增大时,内外温差值总体上呈减小趋势;放飞时刻和放飞日期对超冷现象影响较小,但放飞时间不同,气球上升至设计驻空高度的时间差别较大。该结论可为平流层浮空器总体方案设计和放飞试验提供有益参考。  相似文献   
72.
对战备物资进行分类是选择储备模式的基础和重要前提。把战备物资分类问题抽象为战备物资的军事性和经济性评价问题,设计了物资分类评价指标体系,并对部分指标进行了说明;利用层次分析法确定各指标的权重,运用专家打分法完成指标打分,并对专家打分程序进行优化,增强战备物资分类的可操作性,由军事性和经济性两方面的得分确定战备物资所属类别;最后通过算例证明了分类方法的有效性。  相似文献   
73.
The U.S. Armory in Springfield, Massachusetts, rarely appears in Civil War histories except perhaps as an unexplained statistical wonder. By late 1863, the Armory was the largest single supplier of rifles to Union forces. Springfield Armory workers out-produced over thirty American contractors, making more Army rifles at less cost while providing contractors with gauges, inspectors, and models, even though there were significant wartime private-sector mechanical innovations. This article identifies and explains the factors in the Armory’s success, provides context on contemporary American arms production and rifle models, and argues that the Armory’s methods and performance were among the first if not the first example of mass production in American small arms manufacture. The relative brevity of the Civil War episode, and the fact that it was not repeated in any comparable way at the Armory until World War II, has obscured its significance in American manufacturing history.  相似文献   
74.
Abstract

How do warlords build their legitimacy and eventually exert authority? The case of Afghan leader Ahmad Shah Massoud demonstrates that warlords do not only build legitimacy through the internal provision of goods and services to the population under their control, but also build their legitimacy by projecting authority externally, through the development of their own form of diplomacy. In this article, I show that warlords develop complex and complementary legitimisation strategies that extend beyond their territorial realms to include consequential relationships with foreign actors.  相似文献   
75.
Nuclear deterrence and cyber war seem almost antithetical in their respective intellectual pedigrees. Nuclear weapons are unique in their ability to create mass destruction in a short time. Information or “cyber” weapons, at least for the most part, aim at sowing confusion or mass disruption instead of widespread physical destruction. Nevertheless, there are some intersections between cyber and nuclear matters, and these have the potential to become troublesome for the future of nuclear deterrence. For example, cyber attacks might complicate the management of a nuclear crisis. As well, information attacks on command-control and communications systems might lead to a mistaken nuclear launch based on false warnings, to erroneous interpretations of data or to panic on account of feared information blackout. It is not inconceivable that future nuclear strike planning will include a preliminary wave of cyber strikes or at least a more protracted “preparation of the battlefield” by roaming through enemy networks to plant malware or map vulnerabilities.  相似文献   
76.
Abstract

Terms like ‘support’ and ‘collaboration’ are often used interchangeably to denote a loose set of acts or attitudes that benefit non-state armed groups (NSAGs). However, these terms are seldom defined, and the alternatives available to civilians are rarely identified. Moreover, existing approaches overlook that the interaction between civilians and NSAGs is often one between ruler and ruled, which makes obedience and resistance central. This paper proposes to conceptualize the choices available to civilians as forms of cooperation and non-cooperation, offers a typology, and discusses the implications for theory building on civilian and NSAG behavior, and on the functioning of armed social orders.  相似文献   
77.
卜江  郑彬  文旆 《国防科技》2014,(1):85-87,95
信息技术的飞速发展和广泛运用为心理战的实施开辟了新的更加广阔的空间。当前,拓展深化军事斗争准备和完成多样化军事任务对军队心理战建设提出了新的任务和要求。研究中国近现代心理战的历史沿革发展,特别是辛亥革命时期、土地革命时期、抗日战争时期、解放战争时期、抗美援朝时期中心理战的演变过程,总结经验教训,对于提高信息时代军队心理作战能力有重要启示作用。  相似文献   
78.
王兴国 《国防科技》2014,35(6):112-114
信息化战争已经登上了当今世界的舞台,这是军事领域发生的革命性变化。在信息化战争条件下,传统的战争制胜机理发生的新的变化。  相似文献   
79.
In the late seventeenth century during the Dutch War (1672–1678) and the Nine Years War (1688–1697), French armies relied on small war for the accomplishment of essential tasks and as part of an overall strategy of exhausting their opponents in the Low Countries. The purposes of small war included the imposition of contributions on enemy populations, the destruction of the enemy base of operations, blockades of fortresses, and the general support of campaign armies. The expression ‘small war’ in the French language appeared with growing frequency in the 1690s. Small war can be viewed as both a cause and consequence of the characteristics of these wars. The limited policy goals of Louis XIV the king of France required a strategy that minimised risk and accomplished the goal of reducing if not eliminating the Spanish presence in the Low Countries that bordered the north of France. As French armies increased in size during this period, the demand for specialists at small increased in order to provide security and ensure supply. Small war in the late seventeenth century was thus not ideologically motivated insurgency, but in the minds of French commanders an essential component of strategy and the nature of war.  相似文献   
80.
The insurrection in the Vendée combined open warfare with the methods of petite guerre, ambushing French republican soldiers and cutting their supply lines to Paris. These tactics, when combined with the hatreds generated by a civil war, go far to explain to the cruelty of the conflict in the west and the depth of the hatreds it engendered. In republican eyes the use of guerrilla tactics was unjust and illegitimate, and they denounced their adversaries as common criminals and brigands, portraying them as backward, superstitious, even as subhuman, and in the process justified the savage repression they unleashed against them.  相似文献   
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