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141.
Xiaohui Wu 《The Nonproliferation Review》2013,20(2):317-338
China-U.S. cooperation over the most difficult security problem in Northeast Asia—the North Korean nuclear issue—in essence projects its bigger power game amid the tectonic shifts of Asian geopolitics. The nuclear issue affords a test case to gauge the future posture of China and the United States in East Asia and their partnership in that conflict-prone region. Approaches to resolving this issue must take into account the geopolitical realignment of Asia, Washington's reorientation of relations with its Asian allies, and China's rise as an influential regional player and the subsequent regional response. However, the long-standing mistrust between China and the United States is contributing to a lack of substantial progress in Korean nonproliferation efforts. The declared nuclear test by Pyongyang further put the denuclearization cooperation between China and the Unites States on the line. China-U.S. cooperation in denuclearizing Pyongyang may either produce lasting stability for the region or create ‘‘collateral damage,’’ with the North Korean issue paling in comparison. 相似文献
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143.
Heather Williams 《The Nonproliferation Review》2013,20(3):493-498
George F. Kennan: An American Life, by John Lewis Gaddis. The Penguin Press, 2011. 784 pages, $40. 相似文献
144.
《Arms and Armour》2013,10(1):76-84
AbstractIn an earlier issue, Dr. Timothy Dawson suggested that the fighting techniques found in Royal Armouries MS I.33 may have been influenced by earlier Byzantine sword and shield combat. For evidence, he cites a series of 9th-century ivory carvings depicting similar positions found in I.33. This article is a response to Dr. Dawson’s, in which it is argued that there is ample evidence for similar combat positions being found in Western Europe that both pre-date and are contemporary with I.33. 相似文献
145.
设计了新型半圆管形式的不锈钢板式换热器,对其作为太阳能光电热综合利用一体化系统集热组件的性能进行实验研究。通过新型集热光电热组件及光电组件系统的对比实验,研究该光电热组件在重庆地区夏季应用情况,分析其光电和光热特性。结果表明:在以晴朗为主的天气,半圆管形式的不锈钢板式光电热组件电热系统的电热性能与光电组件系统的相比较,前者的太阳能电池输出功率提高约26.48%,热利用效率提高23.70%以上,新型半圆管形式的光电热组件整体光电热(光电+光热)综合效率可达到25.70%,有效提高了光电热系统的综合效率。新型半圆管形式不锈钢板式换热器的换热面积增大,提高了换热效率,为太阳能光电热综合利用一体化系统在重庆等太阳辐射强度较小地区的应用提供了参考。 相似文献
146.
Ranan D. Kuperman 《战略研究杂志》2013,36(1):1-2
Israel's policy of military reprisals has never seemed to follow any consistent pattern of tit‐for‐tat. On the one hand, not every violent incident was answered with a counterattack. On the other hand, when Israel responded, frequently it employed an excessive amount of force, which was disproportional to the Arab provocation. This behavior has not been the consequence of a premeditated and rational strategy. Instead, it appears to have been the result of a political dispute between alternative approaches regarding the use of military force. The following research analyzes the development of this controversy and how these differences of opinion were resolved. 相似文献
147.
Soul Park 《Small Wars & Insurgencies》2013,24(2):359-381
This paper systematically analyzes the causes of the escalation of violence during the initial stages of the Jeju Island Rebellion and the failure of South Korean counterinsurgency operations. It is argued that four interrelated factors provided the conditions for armed insurgency in the small island of Jeju: inter-agency tension between the Korean National Police (KNP) and the Korean Constabulary; the mainlanders' misinterpretation of the insurgency; the effect of systematic police brutality; and the role of youth groups. Consequently, two counterinsurgency lessons will be drawn from this study: that inter-agency cooperation and coordination at the tactical level between security branches and the incorporation of local population at the micro-level is essential in conducting efficient and effective counterinsurgency operations. 相似文献
148.
针对冲压发动机地面试验应用需求,设计了基于燃气加热方式的煤油加热器,通过试验的方法研究了多个因素对其工作特性的影响规律。研究结果表明,该煤油加热器加热能力强,响应时间短,可在线制备超临界/裂解态煤油;其中,燃气温度、流量和煤油流量是影响煤油加热器工作特性的主要因素,通过控制燃气温度和流量可以大范围调节煤油温度,能满足冲压发动机不同试验工况的应用需求。 相似文献
149.
150.
在领航-跟随编队模式下,设计了一种基于追缉策略的无人机编队会合方法。首先,基于微分几何曲线论和弗雷涅-塞雷标架建立了无人机非解耦三维运动模型,其中将曲率和挠率作为控制量;结合该模型给出了无人机三维编队会合问题的数学描述,它将导弹制导问题中的终端落角约束映射为编队会合问题中僚机的航迹倾角约束,同时引入额外的航迹方位角约束;然后使用特殊正交群的元素来度量长僚机方向偏差,并通过局部坐标映射将其映射为对应李代数空间中的旋量;接着,基于该旋量设计了编队会合几何导引律,并给出相应的曲率和挠率控制指令;最后,分别在长机稳定平飞和转弯机动条件下进行了多机编队会合数字仿真实验,仿真结果显示僚机能够有效地跟踪长机航向并收敛至指定位形,说明了方法的有效性。 相似文献