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171.
针对导弹面临的严酷气动热力环境,基于传统波纹夹芯结构,为导弹设计了一种兼具承载和热防护功能的一体化结构。建立热-结构耦合计算模型,对一体化结构进行结构承载与热防护性能分析,结果表明:一体化结构在高温下具有较好的承载能力;增加一体化结构隔热层与内壁厚度有助于提高导弹的热防护效率。以一体化结构热防护效率最高和质量最小为目标,采用第二代非支配排序遗传算法实现了多目标优化,并认识到:一体化结构热防护效率与质量相互影响,设计时需要需综合考虑。  相似文献   
172.
反恐情报保障是反恐行动的重要组成部分和决策依据。针对新疆边境地区情报力量建设较弱、情报保障手段单一、与有关部门缺乏有效的交流机制等问题,公安边防部门应采取加强情报力量建设、完善情报保障机制、充分利用各种情报手段和加强情报交流与合作等有效措施,不断提高反恐情报保障能力,掌握反恐怖斗争的主动权。  相似文献   
173.
建设科学合理、准确高效的灭火救援作战组织指挥体系,能提高消防部队的组织指挥的能力,以最快、最有效的方法处置各类事故,真正做到"拉得出、冲得上、打得赢"。阐述了建立灭火救援作战组织指挥体系的基本要求,提出了提高灭火救援指挥员指挥水平的对策。  相似文献   
174.
ABSTRACT

While most contemporary analyses of South Asian nuclear dynamics acknowledge the presence of a strategic triangle between the region’s three nuclear players, the primary focus usually remains on the rivalry between India and Pakistan. Discussions of Sino-Indian relations remain limited. This is likely attributed to the stability in the two countries’ relations, yet it is worth asking why this stability exists and whether it is likely to continue in the future. Although China and India have an acrimonious relationship, their asymmetric nuclear capabilities and threat perceptions mitigate the danger of a traditional security dilemma. India may perceive China’s nuclear aggrandizement to be a security threat, but the same is not true of China, which has a vastly superior nuclear force and is largely shaping its nuclear-force structure in response to the threat it perceives from the United States. This dynamic makes a serious conventional or nuclear conflict highly unlikely.  相似文献   
175.
This article intends to explain the outstanding sequence of success and failure exhibited by the FARC, the main Colombian guerrilla since the 1980s. It claims that such sequence is unintelligible unless the adoption by the FARC of a militaristic organizational blueprint at its 1982 7th Conference is taken into account. By building itself like an army, the FARC could boost its combat capacity, maintain its structural integrity, and develop powerful mechanisms that held the whole structure together. At the same time, the militarization of the FARC also entailed significant risks and costs like political isolation and high personnel turnover. After describing the militaristic blueprint, the article compares the FARC with other irregular forces that operated in the Colombian context – a comparison which is important to understand the specificity of the FARC trajectory, as well as the benefits and costs involved in it. The analysis highlights the critical role of organizational dimensions in the explanation of civil war outcomes, and suggests that at least for some problems organizational dynamics should be observed at a low level of granularity.  相似文献   
176.
基于火箭(导弹)级间螺栓法兰连接结构,简化设计并制作了一组原理性实验件,设计准静载加载实验测试系统,进行了两次准静载失效实验,并利用ABAQUS软件建立对应的有限元模型。实验中设计了螺栓力响应信号采集传感器,获得了螺栓力响应数据、加载力与加载位移等多组关键数据。根据实验效果和实测数据,分析了连接结构在准静载荷载作用下的失效机理,并对比验证了有限元模型数值模拟效果和精度与实验吻合较好。研究结论可为箭(弹)级间连接结构承载能力和失效实验设计提供参考。  相似文献   
177.
A variant of established work on the demand for military expenditure is developed based on a practical concept of fiscal space from the perspective of short-term government choices concerning public expenditures. A new indicator, referred to as fiscal capacity, is defined and used as a candidate explanatory variable in an empirical model of European defence spending over the 2007–2016 period. Fiscal capacity is found to outperform simpler measurements of economic conditions, notably GDP growth forecasts, in explaining changes in defence spending efforts as a share of GDP. Regarding security environment variables, the results suggest that Russia has recently come to be seen as a potential military threat by European nations, leading to defence spending increases, the more so the shorter the distance to stationed or deployed Russian forces, and particularly so by those European nations that have a land border with Russia. A prospective exercise is then carried out in order to assess the capacity of EU member states that are also members of NATO to reach NATO’s 2% goal for defence spending over a mid-term horizon.  相似文献   
178.
Supply chains are often characterized by the presence of a dominant buyer purchasing from a supplier with limited capacity. We study such a situation where a single supplier sells capacity to an established and more powerful buyer and also to a relatively less powerful buyer. The more powerful buyer enjoys the first right to book her capacity requirements at supplier's end, and then the common supplier fulfills the requirement of the less powerful buyer. We find that when the supplier's capacity is either too low (below the lower threshold) or too high (above the higher threshold), there is no excess procurement as compared to the case when supplier has infinite capacity. When the supplier's capacity is between these two thresholds, the more powerful buyer purchases an excess amount in comparison to the infinite capacity case.  相似文献   
179.
数字化部队作战能力评估指标体系构建   总被引:3,自引:0,他引:3  
探讨了数字化部队作战能力评估的指导思想和原则,从现代战争系统模型分解图的指标构建思想出发,以系统科学与工程理论为指导,构建数字化部队战争系统模型分解图,将现代战争系统分解成部队与武器子系统、电子信息子系统、指挥决策子系统和综合保障子系统,并分别对各子系统的能力指标内涵进行了详细解释,用信息系统描述了各指标体系的能力构成。  相似文献   
180.
信息技术已经成为当今世界经济与社会发展的主要驱动力,信息产业也已经成为新世纪具有强劲发展实力的经济增长点.民族区域自治地区实施西部大开发战略,实现超越式发展,加快现代化建设的步伐,提高国民经济发展的质量与素质,必须重视对信息化推进和信息产业发展的依靠.但民族区域自治地区推进信息化和发展信息产业的基础条件较差,发展速度亟待进一步加快,发展层次亟待进一步提升,因此,必须要有超常规的强有力措施来推进,需要作为"一号工程"来实施.  相似文献   
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