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1.
The new government in Egypt will have to deal with the following challenges in its foreign policy: the Palestinians, Sinai, the arms race between Israel and Egypt, the nuclear issue, the Suez Canal, and the Tiran Straits. Egypt has to decide what its approach would be toward these issues and as to how to maneuver between its own interests and those of other states such as Israel and the USA. All the sides have to consider their steps carefully in order to avoid an unnecessary crisis.  相似文献   

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《防务技术》2019,15(3):241-253
This is a very timely review of body armour materials and systems since new test standards are currently being written, or reviewed, and new, innovative products released. Of greatest importance, however, is the recent evolution, and maturity, of the Ultra High Molecular Weight Polyethylene fibres enabling a completely new style of system to evolve – a stackable system of Hard Armour Plates. The science of body armour materials is quickly reviewed with emphasis upon current understanding of relevant energy-absorbing mechanisms in fibres, fabrics, polymeric laminates and ceramics. The trend in on-going developments in ballistic fibres is then reviewed, analysed and future projections offered. Weaknesses in some of the ceramic grades are highlighted as is the value of using cladding materials to improve the robustness, and multi-strike performance, of Hard Armour Plates. Finally, with the drive for lighter, and therefore smaller, soft armour systems for military personnel the challenges for armour designers are reported, and the importance of the relative size of the Hard Armour Plate to the Soft Armour Insert is strongly emphasised.  相似文献   

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ABSTRACT

Despite living in a nuclear-weapon state, young Americans are generally ill-informed about weapons of mass destruction (WMD) and their means of control. The result is both widespread apathy toward nonproliferation and disarmament decision making among the general public and a looming personnel crisis within government sectors that enact policy in these domains. Considering that 67 percent of high school graduates in the United States go on to pursue a bachelor’s degree, exposing more undergraduates to nonproliferation and disarmament issues could contribute to addressing both of these challenges. The present study analyzes how these issues are already being taught at select US colleges and universities and explores ways to introduce them to more students that align with current priorities in higher education, such as interdisciplinary learning, digital humanities, and data-science learning. It also proposes concrete steps that the WMD policy community can take to help institutions of higher education integrate these topics more broadly into their curricula. The anticipated result is greater support for education in this important issue area across different stakeholders in academia, as well as increased engagement with these critical issues among a more diverse population of young people.  相似文献   

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Minimum deterrence is a compromise, or halfway house, between nuclear abolition or nearly zero and assured destruction, the dominant paradigm for strategic nuclear arms control during and after the cold war. Minimum deterrence as applied to the current relationship between the United States and Russia would require downsizing the numbers of operationally deployed long-range nuclear weapons to 1000, or fewer, on each side. More drastic bilateral Russian–American reductions would require the cooperation of other nuclear weapons states in making proportional reductions in their own arsenals. In addition, US plans for European-based and global missile defenses cause considerable angst in Russia and threaten to derail the Obama “reset” in Russian–American relations, despite the uncertainties about current and plausible future performances of missile defense technologies.  相似文献   

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In this study, we propose a new parsimonious policy for the stochastic joint replenishment problem in a single‐location, N‐item setting. The replenishment decisions are based on both group reorder point‐group order quantity and the time since the last decision epoch. We derive the expressions for the key operating characteristics of the inventory system for both unit and compound Poisson demands. In a comprehensive numerical study, we compare the performance of the proposed policy with that of existing ones over a standard test bed. Our numerical results indicate that the proposed policy dominates the existing ones in 100 of 139 instances with comparably significant savings for unit demands. With batch demands, the savings increase as the stochasticity of demand size gets larger. We also observe that it performs well in environments with low demand diversity across items. The inventory system herein also models a two‐echelon setting with a single item, multiple retailers, and cross docking at the upper echelon. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2006  相似文献   

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This paper proposes a new appointment rule for the single-server, multiple-customer service system. Unlike previous appointment rules, which perform well only in specific service environments, the new rule can be parameterized to perform well in different service environments. The new appointment rule is presented as a mathematical function of four environmental parameters, namely, the coefficient of variation of the service time, the percentage of customers' no-shows, the number of appointments per service session, and the cost ratio between the server's idle and customers' waiting cost per unit time. Once the values of these environmental parameters are estimated, the new appointment rule can be parameterized to perform well. The results show that new rule performs either as well as or better than existing appointment rules in a wide range of service environments. © 1998 John Wiley & Sons, Inc. Naval Research Logistics 45: 313–326, 1998  相似文献   

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The books under review here, by Robert F. Hannigan, John A. Thompson, Trygve Throntveit, and Adam Tooze, offer an interpretation of Wilsonian internationalism and what happened to it in the 1920s. For Tooze and Hannigan, Wilsonianism was primarily a project to attain American predominance in the world. For Throntveit, Wilsonian internationalism constituted a pragmatic yet radical effort to end competitive power politics. Thompson disagrees with these arguments and asserts that the key to understanding US policy lay in how US leaders conceptualized American power. Thompson’s interpretation is especially compelling in explaining why the United States failed to engage itself more assertively in international affairs in the 1920s – a failure Tooze suggests undermined the viability of the postwar international system.  相似文献   

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From the Barents and the Baltic Sea in the north, through Central Europe and the Balkans, to the Black Sea in the south a range of new subregional groups and cooperation processes have emerged in Europe during the 1990s. Compared to NATO and the European Union, these new subregional groups have received little attention. Their ‘indirect approach’ to security, however, plays an important role in overcoming the legacy of the Cold War, reducing the risks of military conflict and addressing non‐military security challenges. As NATO and the EU expand eastwards, subregionalism is assuming growing importance as a means of avoiding new ‘dividing lines’ in Europe. After the wars in Bosnia and Kosovo, subregionalism is also gaining importance as a means of building cooperation in South‐Eastern Europe. The challenge for the future is to give more substance and depth to Europe's new subregional cooperation frameworks.  相似文献   

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In 2015, Brazil has taken steps toward re-consolidating its domestic defense industry. In the 1980s, Brazil built a dynamic and diversified defense industry. The state-driven effort resulted in a tripod strategy, where the state, state-run companies, and their private sector became the pillars of Brazil's defense industry. Brazil developed an export-driven defense industry; where close to 80–90% of its output was exported to Latin American, African, Arab, and Asian nations. In the 1980s, Brazil became the world's fifth largest exporter of defense products and services, exporting to over 40 countries. In the 1990s and 2000s, Brazil's defense industry suffered a dramatic reduction in size, diversification, and momentum. Successions of domestic political and economic policies have relegated Brazil's once emerging defense industry to a marginal position in the global defense industry. This article analyzes future prospects, challenges, and growth strategies for Brazil's defense industry.  相似文献   

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A striking difference between the EU’s 2016 Global Strategy and its 2003 predecessor is the ubiquity of resilience as a new leitmotif, understood as the ability of states and societies to reform, thus withstanding and recovering from internal and external crisis. Resilience provides a middle ground between over-ambitious liberal peace-building and under-ambitious stability, (re)directs attention to local resources and practices, and is ambiguous enough to be acceptable to everyone. The Global Strategy’s leitmotif is an example of the rise and spread of resilience in international discourses about crisis management and humanitarian emergencies. Although there are risks inherent to the way in which resilience reframes risks and crises, its added value lies in its power as convening concept, opening up international organizations to new ways of thinking and working, and providing a common ground for engagement.  相似文献   

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创新是治党治国之道,也是引领党和国家发展的第一动力.党的十八大报告强调指出,"科技创新是提升社会生产力和综合国力的战略支撑,必须摆在国家发展全局的核心位置".国防科技大学作为军队科技创新的重要有生力量,既要从战略和全局高度把握新发展理念,又要立足具体领域扎实推进实践创新.同时,在推进创新的过程中,要以辩证思维把握新发展...  相似文献   

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分析了RSA和DES的算法优点和安全弱点,设计了一个新的密码算法方案。该方案以类FEISTEL结构为基础增强了左右两半部分结构的安全设计,利用了RSA进行密钥分配,并以序列密码算法的生成原理改变了固定密钥的缺点。该新方案具有一次一密的特点,给破译者获得大量的明密文对造成了很大的困难,可较好地抵抗差分分析与线性分析,是一种安全性较强的加密方案。  相似文献   

20.
对越轨功能的新认识   总被引:1,自引:0,他引:1  
对越轨功能的认识具有重要意义,但以往对越轨功能的认识仅停留在现象层面,深入到人类发展的内在过程和社会运行机制层次加以分析,可以发现越轨有若干独特的积极功能。由对越轨的这种认识,可以恰当地确定我们对越轨的态度和应对策略。  相似文献   

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