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221.
建立了三组元液体火箭发动机性能计算模型、单级入轨可重复使用运载器质量模型和弹道模型,以起飞质量为目标函数,优化得到了实现单级入轨的发动机基本参数。结果显示:三组元发动机性能比氢氧发动机高10%。本研究是三组元发动机系统设计和分析的基础。 相似文献
222.
M. Rashel Hasan 《Defence and Peace Economics》2017,28(2):188-207
We examine how armed conflict effects financial development in a cross-country setting using dynamic panel data analysis in a panel of 66 developing countries for the period 1985–2010. Financial development is measured by M2 as a share of GDP, and credit allocated to private sector by banks as a share of GDP. Our findings suggest that armed conflict has a significant adverse effect on financial development. Simultaneously, the quality of governance is always highly significant and conducive to the financial development. The quality of governance is more salient in determining financial development compared to low- and medium-intensity armed conflict; however, the quality of governance cannot entirely offset the adverse impact of high-intensity armed conflict on financial development. 相似文献
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“经济自由”与“自由经济”辨析——理想与政策 总被引:3,自引:0,他引:3
黄展骥 《兵团教育学院学报》2001,11(1):6-9
自由主义的实践历史 ,是从争取宗教自由开始 ,继而争取政治自由 ,直到近代和现代 ,却转移集中争取经济自由。“经济自由”虽然是个极重要的课题 ,但是一般论著却把目标 (理想 )性的经济自由混淆作手段 (方法 )性的自由经济 (制度 )。相应地 ,一般论者也把“经济自由主义”错误地狭限于“放任 (自由 )经济制度”以满足一小撮人的经济自由。再者 ,本文认为高寿昌先生早在 6 0年代在外地发表的《经济的自由主义》一文很具卓见和勇气 ,现在试图运用 (广义 )逻辑学把它精确化 ,特别是严格区分“经济自由”与“自由经济(制度 )” ,以显示逻辑分析的重大实用价值 相似文献
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Dimitri Percia David Marcus Matthias Keupp Ricardo Marino Patrick Hofstetter 《Defence and Peace Economics》2019,30(1):111-127
The Swiss Armed Forces are suffering from a structural deficit of militia officers despite good pay and a general supportive attitude in the population. Whereas, prior studies have focused on motivation to explain understaffing in armed forces, we offer an alternative approach based on opportunity cost. We model decision alternatives both within and outside a military organization, taking private sector employment as the reference point. We then monetize opportunity costs of leisure, fringe benefits, and private sector income not compensated. Our results suggest that in terms of opportunity cost, service as a militia officer is the least attractive option, an effect that we believe explains the persistent staff deficit. Implications of these findings for the literature and recruitment policy are discussed. 相似文献
226.
2018年10月,美国宣布单方面退出《中导条约》。《中导条约》是美苏两国在冷战后期达成的,并得到了切实执行的条约,对于维护冷战后全球战略平衡发挥了至关重要的作用。冷战后,俄美曾经企图将《中导条约》多边化,构建俄美新型战略关系,但最终反目成仇,使得俄美关系严重倒退,并迈入新的相互战略遏制的时代。 相似文献
227.
张颖 《国防科技大学学报》2019,41(6)
针对近地卫星数传时的信道时变性和严重的Ka频段雨衰现象,采用自适应编码调制(ACM)技术能够充分利用链路资源,相对于传统的固定编码调制方式,进一步提高了链路的数据吞吐量。提出了近地卫星Ka频段数传链路ACM模式设计方法,在降雨环境下建立Ka频段数传链路模型,根据信道状况确定ACM选用模式;采用基于导频符号的最大似然信噪比估计算法结合移动平均的平滑方法实现信道估计,有效地减小了估计值的波动。仿真结果表明,无论晴天还是雨天,采用提出的卫星数传链路ACM模式设计方法,能够在保证系统可靠性的同时获取较高的数据吞吐量。 相似文献
228.
Maja Garb 《Defense & Security Analysis》2018,34(1):3-15
Approximately 470,000 refugees and migrants passed through Slovenian territory between September 2015 and March 2016, creating a crisis that required a great deal of organisational and field work on the part of many governmental and non-governmental institutions. In the social sciences, a discourse on “security versus humanitarian approach” on the refugees and migrant issue appeared; however, the article goes over such a discourse and deals with roles and problems of different institutions – mostly the military – that responded to the crisis. Namely, coping with the crisis was characterised by significant institutional adjustments, difficult co-ordination, and intense public debate. The Slovenian Armed Forces were included in this process as support for Civil Protection and Police. The military’s role followed the military missions defined by the Defence Act; however, the government also proposed some changes to the act that were met with some doubts on the part of the public and different institutions. 相似文献
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