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71.
    

The impact of defence expenditure on the economy has been widely studied through different types of models. However, the results from these studies have not reached definitive conclusions, and have left a gap in the analysis of the impact of defence R&D expenditure at the economy level. Defence R&D has specific characteristics, which lead to market failures: public good, high risk and uncertainty, national security. Also, defence R&D creates two types of externalities: negative (crowding-out), and positive (spin-off). Crowding-out is the major economic debate about defence R&D. This paper analyses the crowding-out hypothesis by applying three types of models for the UK case: supply, demand, and demand-supply models. From these three models the most reliable is chosen and applied to the individual cases of France, Germany, Japan and USA. The paper also reports the results for the pooled data of these five countries, and for four error component models. The results from estimating such models shed light on the defence R&D crowding-out hypothesis.  相似文献   
72.
    
If international terrorism is on a rising trend, an important source of confirmation or refutation of this is time‐series data on terrorist activity. Using chiefly data collected by the RAND/MIPT consortium we show using basic statistical analysis that in the period 1968–2005 the yearly number of all international terrorist incidents shows no trend over time, but fluctuates year on year in a random manner. On the other hand some indicators do show a definite trend over time, principally the steady rise in the number of incidents that are death‐dealing in nature. A further conclusion is drawn, showing that the proportion of these incidents leading to deaths above a given level is virtually fixed.  相似文献   
73.
    
The death of Jean Charles de Menezes on the London Underground in 2005 remains a horrifying example of what happens when counterterrorism goes wrong. One of the extraordinary features of the shooting was the remarkable number of special elements, police units, military Special Forces, and unusual procedures and tactics involved in the incident. This article attempts to assess the causal significance of the special dimension in the horrific chain of circumstances. It does so by interrogating numerous explanations for the tragedy and highlighting the role of the special factor. The Stockwell shooting remains very important today because it casts a sharp and somewhat harsh spotlight on the particular pitfalls of special responses, measures and units to the multitudinous threats posed by international terrorism in the twenty-first century.  相似文献   
74.
为研究干扰条件下防空兵通信装备系统效能,在ADC模型的基础上构建了ADCF系统效能模型,并结合实例对模型进行了仿真分析。仿真结果显示,该模型能较好反映敌方干扰对通信装备系统效能的影响。提出了干扰条件下提高防空兵通信装备系统效能的措施。  相似文献   
75.
    
This paper looks at the impact of military technology diffusion on military assistance operations (MAO), in the United States known as Security Force Assistance or SFA. The discussion looks conceptually at the role of technological change and how it interacts with martial cultures in military assistant operations. I argue that growing trends in science and technology suggest potential conflicts between culture and technology. Relying on a culture-technology model drawn from anthropology, the paper contends that new technologies will present increasing challenges for the emerging MAO landscape. The paper will illustrate that the techno-science gap will continue to grow as innovations such as robotics, sensors, and networks continue to develop. Finally, the paper will look at ways to overcome this conflict between culture and technology.  相似文献   
76.
77.
武警官兵在执勤过程中经常会遇到外国人,学习一些执勤英语十分必要。目前,武警指挥院校开设了《武警执勤实用英语》这门选修课,笔者在备课过程中发现,教材中有一些译文不是很准确,因此,撰写本文和编者商榷。本文从武警执勤用语的翻译现状入手,通过分析武警指挥院校正在使用的名为《武警执勤实用英语》教材中的译文,探讨了武警执勤用语的翻译。笔者提出在翻译过程中,译者应把握以下几点:术语翻译需谨慎、充分了解术语的内涵、避免直译出错、慎选词语、注意文化差异、使用对应文体、统一译文。最后,笔者提出了定期修改教材的建议。  相似文献   
78.
建立了一种螺旋轮式管道检测机器人驱动系统的三维模型,对驱动系统通过凸台和三通的能力进行了动力学分析。研究了预紧弹簧刚度和预紧力对螺旋轮过凸台能力的影响,讨论了过三通时的几何约束和动力学约束条件,并通过算例分析,验证了模型的正确性。  相似文献   
79.
中国共产党成立90年来,带领中国人民赢得了民族独立和人民解放,初步实现了国家的繁荣昌盛和人民的共同富裕。回顾历史,审视现实,放眼全球,展望未来,只有坚持党的领导,中华民族才能不断走向新的胜利。  相似文献   
80.
This article challenges the widely held belief that that the United States ‘won the war but lost the peace’ following the war with Iraq in 1991. Fears of a resurgent Iraq grew throughout the decade, despite abundant evidence that Iraq was becoming desperately weak and was no longer a threat to regional security. In fact, the United States won the war as well as the peace by any meaningful definition of the term. The article also discusses the reasons why US policymakers and observers convinced themselves that they had lost. The final section considers implications for strategy and policy in wars of limited objectives.  相似文献   
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