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661.
This paper analyses the impact of terrorist activity on international tourist flows. To this end, we have estimated a cross‐sectional gravity equation for tourism from the G‐7 countries to a sample of 134 destinations over the period 2001–2003. Within this framework, we evaluate the deviation from ‘normal’ tourist flows due to terrorist activity, which is considered as negative advertising for the affected country. The analysis suggests that both domestic victims and international attacks are relevant factors when foreign tourists make their choice. This result is robust under alternative specifications. Moreover, the impact of terrorism is more severe in developing countries.  相似文献   
662.
Previous research has shown that the duration of a civil war is in part a function of how it ends: in government victory, rebel victory, or negotiated settlement. We present a model of how protagonists in a civil war choose to stop fighting. Hypotheses derived from this theory relate the duration of a civil war to its outcome as well as characteristics of the civil war and the civil war nation. Findings from a competing risk model reveal that the effects of predictors on duration vary according to whether the conflict ended in government victory, rebel victory, or negotiated settlement.  相似文献   
663.
Probing the technology in the production of US national defence by using a dynamic cost‐function model with adjustment costs, this paper evaluates the effect of reducing the level of national defence on the defence budget saving. Our inquiry involves estimating the defence production structure without output data for non‐market goods that are normally unavailable. Our findings include: (i) the United States behaves rationally to minimize cost in the production of national defence; (ii) the adjustment costs are larger in disarmament than in military build‐up; (iii) due to the adjustment costs peculiar to disarmament, the defence budget saving from disarmament appears small, but cutbacks allow great savings on the defence budget.  相似文献   
664.
Abstract

This study estimates a three-sector Feder–Ram model using US annual data for 1965–2014 to confirm the externality of defense expenditure in the United States. Although the model is often used in the literature to scrutinize whether this effect exists, a flaw intrinsic to this model is the appearance of multicollinearity. In this study, I introduced novel techniques, namely: the standardization and estimation of a simple slope, to estimate the model. The results are as follows. First, I prove that the multicollinearity problem can be resolved by standardization. Second, externality, which is judged to conventionally exist, is not found. Third, increases in defense expenditure bring about positive but limited economic growth when the ratio of private to defense expenditure in the previous year ranges from 5.09 to 6.82%. By re-estimating the model, this study contributes to developing the Feder–Ram model within the related literature.  相似文献   
665.
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   
666.
667.
George F. Kennan: An American Life, by John Lewis Gaddis. The Penguin Press, 2011. 784 pages, $40.  相似文献   
668.
概念模型验证是保证和提高仿真可信性的重要手段,是建模与仿真VV&A中的重点和难点.首先将概念模型的验证方法划分为非形式化方法、静态方法、动态方法和形式化方法4类,并提出了一种基于本体推理的概念模型验证方法,然后对各种方法的基本思想、基本原理、基本过程、适用对象、优缺点进行全面的分析总结,明确了各种方法的优缺点和适用范围,为如何选用各种验证方法提供参考,也明确了下一步应重点研究的问题.  相似文献   
669.
为评估HIGHT轻型分组密码抗故障攻击能力,基于单字节故障模型,提出一种改进的HIGHT故障攻击方法.首先在HIGHT最后1轮注入单字节故障恢复SK124和SK1262个轮密钥,然后增加故障注入深度,在HIGHT倒数第5轮注入单字节故障恢复HIGHT另外10个轮密钥,从而恢复HIGHT的全部主密钥.实验结果表明:仅需22次故障注入即可恢复HIGHT全部128位主密钥,优于现有故障攻击方法所需的32次故障注入.  相似文献   
670.
将软件设计中的面向对象思想扩展到系统设计中,针对柴油机实车运行在线监测中的变速变载及空间有限等问题,基于CAN总线的可靠性、信息传输的实时性和多主工作方式,设计分布式智能监测节点和上位机监控中心.分布式监测节点同步采集柴油机运行数据并进行降噪和简单特征提取后,将实时采样数据和在线监测结果上传至基于嵌入式PCI04的上位机监控中心,进行二次特征提取和智能模式识别,从而实现柴油机在线状态监测与故障预警和诊断.  相似文献   
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