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91.
This article investigates the demand for military expenditure for a sample of key Asia-Pacific countries. Spatial panel demand estimates are presented for three joined spatial units using a fixed-coefficient spatial lag model based on a two-step efficient GMM estimator. Spatial autoregression estimates are next presented for 1991–2015, founded on alternative kinds of country connectivities, such as contiguity, inverse distance, discrete distance, and power-projection considerations. Finally, 11 select countries’ demands for defense equations are estimated using seemingly unrelated regressions. From alternative perspectives, these estimated models indicate how Asia-Pacific countries respond to the defense spending of other countries. In the spatial runs, free riding is prevalent despite the growing military might of China, which apparently is not generally viewed as a threat. For the sample period, the projection of Chinese or American power is a relevant spatial factor. The main threat is reflected in non-U.S. allies’ reaction to U.S. allies’ defense spending during 1991–2015 and to Chinese defense spending after 2002.  相似文献   
92.
针对现有高维多目标可视化技术不能有效显示决策偏好信息这一难题,提出一种基于径向轴图的交互式Pareto前沿可视化决策方法。进行标准化适应度函数处理,消除量纲差距;根据交互更新的轴向量矩阵建立最小二乘问题模型,通过Moore-Penrose广义逆矩阵方法求解投影点,从而获得Pareto前沿分布图。该方法能够有效显示目标各维度信息,直观呈现决策偏好,动态表现目标性能趋势。通过实验与传统可视化技术对比分析,验证了该方法的有效性和实用性。  相似文献   
93.
This article offers a comprehensive analysis of the database ‘Mémoire des hommes’, which is a record of more than 1 million French soldiers officially recognized as dead during the World War I (WWI). Integrating this source with the 1911 census, we evaluate the potential numbers of recruits by French regional department. From this, a model identifies the factors affecting the number of deaths. While demographic factors are the principal determinants, adding significant economic, political and spatial factors reduces the unexplained variance between regions and significantly improves the explanation of the disparity in the number of deaths by region.  相似文献   
94.
依据空间信息支持现代作战的主要内容,介绍了五大类空间信息状况,分析了新概念武器高能激光的基本原理,并就其应用过程建立了UML模型。在此基础上,设计了空间信息支持高能激光武器应用系统的框架,并就高能激光武器对空间信息的需求进行了重点分析,而后以信息的转换与传递为主线,探讨了高能激光武器运用空间信息的流程。最后对该领域研究的趋势和发展前景做出了展望,并提出对其未来发展的要求。  相似文献   
95.
《防务技术》2020,16(4):910-921
Non-cylindrical casings filled with explosives have undergone rapid development in warhead design and explosion control. The fragment spatial distribution of prismatic casings is more complex than that of traditional cylindrical casings. In this study, numerical and experimental investigations into the fragment spatial distribution of a prismatic casing were conducted. A new numerical method, which adds the Lagrangian marker points to the Eulerian grid, was proposed to track the multi-material interfaces and material dynamic fractures. Physical quantity mappings between the Lagrangian marker points and Eulerian grid were achieved by their topological relationship. Thereafter, the fragment spatial distributions of the prismatic casing with different fragment sizes, fragment shapes, and casing geometries were obtained using the numerical method. Moreover, fragment spatial distribution experiments were conducted on the prismatic casing with different fragment sizes and shapes, and the experimental data were compared with the numerical results. The effects of the fragment and casing geometry on the fragment spatial distributions were determined by analyzing the numerical results and experimental data. Finally, a formula including the casing geometry parameters was fitted to predict the fragment spatial distribution of the prismatic casing under internal explosive loading.  相似文献   
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