排序方式： 共有113条查询结果，搜索用时 15 毫秒
61.
Vusal Musayev 《Defence and Peace Economics》2016,27(3):378-391
This investigation re-examines the potential sources of positive externalities for the relationship between military spending and economic growth using recent advances in panel estimation methods and a large data-set on military expenditure. The investigation provides a new analysis on the relationship between conflict, corruption, natural resources and military expenditure and their direct and indirect effects on economic growth. The analysis finds that the impact of military expenditure on growth is generally negative as in the literature, but that it is not significantly detrimental for countries facing higher internal threats and for countries with large natural resource wealth once corruption levels are accounted for. 相似文献
62.
Emeka Thaddues Njoku 《Small Wars & Insurgencies》2019,30(6-7):1233-1263
ABSTRACTThere is a dearth of studies on indirect victims of sexual violence in counter-terrorism efforts. Using Nigeria as a case study, this paper argues that global and state-level counter-terrorism policies have generally failed to account for the psychological effects of the engagement of female NGO workers in counter-terrorism operations or mitigating the effects of terrorism in conflict zones. Specifically, there has been an increase in sexual violence perpetrated by some members of the security agencies involved in counter-terrorism operations in North-eastern Nigeria. As a result, female NGO workers carry out Medicare, psychosocial counselling and advocacy for these victims. Female NGO workers become exposed to the trauma of victims of sexual violence, which affects their mental health and thus performances in counter-terrorism activities in the country. This altered their worldview on issues of safety even among secured locations or among the presence of security agents and reinforced feelings of powerlessness. 相似文献
63.
《防务技术》2014,10(3):261-268
To prepare the porous NC-based (nitrocellulose-based) gun propellants, the batch foaming process of using supercritical CO2 as the physical blowing agent is used. The solubilities of CO2 in the single-base propellants and TEGDN (trimethyleneglycol dinitrate) propellants are measured by the gravimetric method, and SEM (scanning electron microscope) is used to observe the morphology of foamed propellants. The result shows that a large amount of CO2 could be dissolved in NC-based propellants. The experimental results also reveal that the energetic plasticizer TEGDN exerts an important influence on the pore structure. The triaxial tensile failure mechanism for solid-state nucleation is used to explain the nucleation of NC-based propellants in the solid state. Since some specific foaming behaviors of NC-based propellants can not be explained by the failure mechanism, a solid-state nucleation mechanism which revises the triaxial tensile failure mechanism is proposed and discussed. 相似文献
64.
多阶段含延缓纠正的可靠性增长试验,其各个阶段内的试验数据分别服从参数不同的Weibull过程.针对现场样本少、传统的可靠性评估方法实施困难的问题,首先在获得各阶段形状参数的基础上,对各个阶段截尾时刻的失效强度建立顺序约束关系.然后,运用Bayes方法融合先验信息,获得最末阶段截尾时刻的失效强度的期望与置信上限.该结果融合了历史阶段的样本信息,优于仅利用单个阶段样本的分析结果,适用于多阶段可靠性增长试验的综合评估. 相似文献
65.
针对火箭发动机分阶段试验,每阶段试验后对发动机出现的故障分析、归零的情况,提出等效试验数据的概念,结合Bayes方法对系统的可靠性增长试验进行评估,并在此基础上给出可靠度的增长分析,最后给出实例进行说明。 相似文献
66.
本文导出了一般TE_(no)模矩形波导结构潘尼管的色散方程,对潘尼管作了更明确的解释,并详细计算了TE_(20)模潘尼管的色散方程,得到其基波和第三次谐波同步谐振的色散曲线。该曲线表明,潘尼管在基波谐振上有1.5%的增长率,而在第三次谐波上有0.8%的平均增长率。此外,用非线性理论分析基波和第三次谐波同步谐振时的工作情况,给出了电子饱和时的电子分布图。在常直流磁场下优化结果表明,潘尼管在其次谐振时有51%的高效率和QP_w=9949.9MW 的输出功率,而在第三次谐振时有11%的效率和QP_w=1741.8MW 的输出功率。 相似文献
67.
王中伟 《国防科技大学学报》2008,30(3):32-36
为进行锥形液膜雾化过程分析,研究锥形液膜的Kelvin-Helmholtz稳定性问题,应用小扰动假设,建立了锥形液膜数学模型、轴对称扰动运动的控制方程和边界条件,采用分离变量法求解线性偏微分扰动方程组,经过严格的数学推导,得到了锥形液膜内外表面扰动波增长速率特征方程.当液膜锥角为零时,与环形液膜扰动波特征方程一致;当液膜锥角和液膜内径为零时,与圆射流扰动波特征方程一致,表明导出的锥形液膜扰波动方程是合理的. 相似文献
68.
预冷器换热通道空气侧壁面的结霜对预冷发动机整体性能具有重要影响.通过实验研究了三种具有不规则表面形貌结构的试件(Ra=0.97 µm,Ra=1.78 μm,Ra=1.92 μm)在高温环境(Ta=50 ℃)下的结露/结霜过程.主要研究了环境温度(Ta取50℃和18℃)、表面温度(Tw取-10.9℃、-23.0℃、-28.0 ℃)以及表面形貌结构对液滴凝结及霜层生长特性的影响,并将霜层的致密化机理进行了总结分类分析.实验结果表明,环境温度越高,表面温度越低,霜晶生长周期越短.在三种试件表面,越靠近试件边缘,凝结液滴出现时间越早,长大越快.此外,还发现表面形貌结构对液滴的凝结及霜层生长全过程均有影响,并将表面形貌结构对凝结的影响机理进行了初步分析,但是不规则表面形貌结构对霜层生长的影响机理仍需进一步深入研究. 相似文献
69.
对于延缓纠正模式的可靠性增长试验,阶段内产品的寿命服从失效率为常数的指数分布,而阶段间的可靠性有阶跃增长,通常考虑以增长因子进行阶段间的信息传递,增长因子的确定成为关键.首先分析常用的ML-Ⅱ确定方法的局限性,提出改进的ML-Ⅱ方法,并对阶段末的可靠性作出Bayes评估.最后仿真示例表明了改进方法的有效性. 相似文献
70.
The Political Economy of Military Spending in the United States, Alex Mintz (ed), London and New York: Routledge, 1992, pp x, 334; ISBN 0–415–07595–5 Penser La Guerre, Penser L'Economie, Christian Schmidt, (Paris: Odile Jacob, 1991), 350p. Military Production and Innovation in Spain, Jordi Molas‐Gallart, Chur (CH): Harwood Academic Publishers, 1992, pp. vii, 212; ISBN 3–7186–5280–3 相似文献