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81.
Arms transfers provide exporters an avenue to provide security to other states while gaining economic benefits. Arms transfers provide importers an avenue to gain security without having to rely on alliances. Past research uses aggregate measures of the monetary or security value of major weapon system transfers without accounting for strategic differences in possible use in interstate and civil conflict. This article presents a data set on interstate transfers of major weapon systems between 1950 and 2010 building upon Stockholm Peach Research Institute’s Arms Trade Register with several improvements. First, it disaggregates land weapons and air weapons into categories reflecting their strategic capabilities. Second, model level characteristics (e.g. age, speed, and range) are drawn from Jane’s Defence sources. Additionally, the data set covers a larger range of time and states than previous data sets categorizing arms. To demonstrate the usefulness, this article first presents summary statistics of the data set and then replicates an earlier test to show that the effect of human rights and regime types on United States transfers differs across the categories of arms compared to alternative measures of arms transfers.  相似文献   
82.
针对群系统编队跟踪问题,提出一种满足线性二次型调节器性能指标的优化控制方法。建立编队跟踪问题的数学描述和设计编队跟踪控制协议。给出群系统实现编队跟踪的充要条件,借助李雅普诺夫第二方法分析系统的稳定性。得到了控制协议能够最小化线性二次型调节器性能指标的拓扑条件,设计了编〖BHDWG8,WK10YQ,DK1*2,WK1*2D〗〖XCWL.TIF;%129%129〗听语音 聊科研与作者互动 队跟踪算法。仿真实验验证了控制方法的有效性。  相似文献   
83.
《防务技术》2022,18(10):1842-1851
In this study, the approximate and exact solutions for the stationary-state of the solids model with neglecting reactant consumption for both non-uniform and uniform temperature systems were applied on gas ignition under a constant pressure condition. The criticality conditions for a slab, an infinite cylinder, and a sphere are determined and discussed using dimensionless temperatures under constant ambient and surface temperatures for a non-uniform temperature system. Exact solution for a Semenov model with convection heat loss was also presented. The solution of the Semenov problem for constant volume or density as a solid and constant pressure were compared. The critical parameter δ is calculated and compared with those of Frank-Kamenetskii solution values. The validation of the calculated ignition temperatures with other exact solution and experimental results were offered. The relation between critical parameters form Semenov and F.K. models solution was introduced.  相似文献   
84.
Some of the most active arms races are taking place between developed and less developed countries. The inability of less developed countries to compete financially, as well as technologically, with developed countries may be forcing the former to acquire terror weapons (TWP). The Iran–Iraq war in the 1980s and the events of 9/11 proved that the use of TWP is no longer a mere threat; there are several organizations and countries that will not hesitate to use them. This study develops a model of resource allocation in an arms race between a developed country that is characterized by state‐of‐the‐art technology and high GDP, and a less developed country whose technological capability and GDP are much lower. The model is used to predict the optimal mix of weapons of the two countries that are engaged in the arms race. Applying the model to the arms race between Israel and Syria demonstrates its use.  相似文献   
85.
基于复杂网络理论,分析了信息化作战系统网络结构,构建了传统作战系统和信息化作战系统拓扑模型的生成算法,并通过对传统作战系统和信息化作战系统结构拓扑模型度量性质的比较,说明了信息化战争下的作战系统结构特点,为进一步研究网络化战争提供了良好的模型基础.  相似文献   
86.
ABSTRACT

The Treaty on the Non-Proliferation of Nuclear Weapons (NPT) allows states to exempt nuclear material from international safeguards for use in nuclear submarine programs. This material, however, could be diverted for nuclear weapons purposes without the knowledge of inspectors, creating a potentially dangerous loophole in the treaty. This article argues that exercising that loophole today would amount to admitting a nuclear weapon program, making it a particularly poor pathway to a weapon for a potential proliferant. Still, if states like Brazil ultimately exempt nuclear material from safeguards for a nuclear submarine effort, they could set a dangerous precedent that makes it easier for others to use the loophole as a route to a nuclear weapon capability. There are several policy options available to mitigate the damage of such a precedent; most promising is the prospect of a voluntary safeguards arrangement that would allow international inspectors to keep an eye on nuclear material even after it has been dedicated to a naval nuclear propulsion program.  相似文献   
87.
太阳能热推力器二次聚光器再生冷却过程   总被引:1,自引:0,他引:1       下载免费PDF全文
为克服太阳能热推力器折射式二次聚光器容易破裂的缺点,本文采用再生冷却技术,对二次聚光器与推力室进行了一体化设计,并对该过程进行了流动与传热仿真。仿真结果表明,该设计可有效地降低聚光器的工作温度至1600K以下,热应力分析表明可有效降低其破裂的可能性。同时该设计可预热推进剂至500K以上,提高了系统的能量利用效率。通过进一步对吸收腔内的热辐射分析发现,工质流动对吸收腔壁温影响较小,吸收腔壁面仍然可以维持2400-2600K的高温。  相似文献   
88.
混合总线网络化ATS可整合多种总线测试仪器/设备功能,发挥不同总线测试平台优势,增强系统灵活性,节约新系统的构建成本.针对靶场测试设备现状,研究了基于网络化测试技术的混合总线ATS构建方法.提出了混合总线网络化ATS硬件结构并设计了利用接口适配器和利用网关设备2种组网方案.  相似文献   
89.
大型舰船电力系统网络重构研究   总被引:7,自引:1,他引:6  
大型舰船电力系统的出现使供电方式由原来的辐射状向环形发展,其网络重构是一个崭新的问题.文中给出了大型舰船电力系统的网络拓扑结构并综合考虑了线路容量限制、节点电压约束及供电负荷优先性的重构数学模型,保证了各种情况下最大限度地给负荷供电.将规划遗传算法应用于所建模型的求解,并应用算例验证了此解法的可行性.  相似文献   
90.
为提高潜艇推进效率,降低潜艇阻力和噪声,提出了一种潜艇内王推进系统及其结构布局,初步建立了内置推进系统的理论分析方法和设计思路.对推进系统的管道进行了参数化设计,并借助计算流体力学软件,用体积力代替螺旋桨产生的力场,对不同管道参数下的潜艇周围及管道内部的流场进行了数值模拟,结果表明:增大管道的进口面积可以减小管道阻力,...  相似文献   
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