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241.
基于分布式哈希表(DHT)的P2P查找经常受到在底层网络中路由时无必要的路径长度增加的影响.另外,DHT在处理复制方面也有一定的缺陷.文中探讨了解决这些问题的方法.对使用Bloom filters作为资源路由的方法做了简要回顾,并较为详细地阐述了在资源分散的覆盖网络中使用距离加权Bloom filter的网络路由算法.对该算法进行了仿真测试,证明了其有效性.  相似文献   
242.
设计安全策略模型时应考虑安全策略的时序特性和灰色特性,还应综合考虑保密性、完整性和可用性三方面的需求。已有的安全模型没有描述时序性和灰色特性,而且一般只侧重描述保密性或完整性。为此,本文提出了动态灰色时序系统(简称DGTS)。本文详细描述了DGTS,以及基于DGTS的动态语义设计的灰色时序安全策略规范语言GTSL。  相似文献   
243.
This paper extends the joint product model of military alliances to apply to the new strategic doctrine adopted by NATO in the 1990s. In particular, a choice must be made between protecting one's own territory and pooling forces for an alliancewide rapid reaction force. This new model accounts for a host of externalities and their implications for burden sharing, full financing, and allocative efficiency. The Pigouvian taxes that adjust for force thinning and attack deflection are shown to finance optimal border‐protecting forces under a variety of circumstances. Second‐best considerations arise owing to the pure publicness of rapid reaction forces. The ideal toll arrangement does not currently characterize NATO financing, nor is it likely to do so.  相似文献   
244.
The eastern Democratic Republic of Congo (DRC) has been characterised by chaos and insecurity for a number of years, but the rise of the M23 rebellion in 2012 once again highlighted just how dire the humanitarian and security situation is. For most of 2012, the crisis was addressed through negotiations between M23 and Kinshasa, mediated by the International Conference on the Great Lakes Region (ICGLR). However, 2013 marked the signing of the Peace, Security and Cooperation Framework Agreement (PSC Framework), and the United Nations Security Council's adoption of Resolution 2098, which contains the mandate of the long-awaited Intervention Brigade (IB). The PSC Framework calls on Kinshasa to implement substantial political reforms while also urging the neighbours of the DRC to stop interfering in its internal affairs. The IB is mandated to carry out targeted operations against the so-called ‘negative forces’ that operate in the eastern DRC. For now, hope of resolving this ongoing crisis hinges on the continuing ICGLR negotiations, the implementation of the PSC Framework and the success of the IB. However, there are critical questions about all of these processes that need to be answered and understood, as the expectations for these processes – especially in the case of the IB – are extremely high. Will the ICGLR manage to negotiate a peace agreement and will the IB succeed, or will they go down in history as yet another failure to save the eastern DRC?  相似文献   
245.
ABSTRACT

There is a lingering disagreement among scholars on how the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) affects nonproliferation and disarmament outcomes. Drawing on constructivist scholarship on international norms, this article examines the extent of the NPT's effect in the case of Ukraine's nuclear disarmament. In the wake of the Soviet Union's collapse, Ukraine found itself host to the world's third largest nuclear arsenal. Despite Ukraine's initial commitment to become a non-nuclear state, it proceeded along a difficult path toward NPT accession. Most controversial and directly at odds with the NPT was Ukraine's claim to ownership of its nuclear inheritance as a successor state of the Soviet Union. This article argues that, while much domestic discourse about the fate of these nuclear weapons was embedded in the negotiation of Ukraine's new identity as a sovereign state vis-à-vis Russia and the West, the NPT played an important, structural role by outlining a separate normative space for nuclear weapons and providing the grammar of denuclearization with which Ukraine's decision makers had to grapple.  相似文献   
246.
Greece and Turkey are both members of NATO and are two of the principal players in the Balkan region. Their respective defence burdens (i.e. the share of military expenditure to GDP) are the highest in NATO. Their bilateral relations are marred by serious friction and conflict of interest and have on a number of occasions come close to an armed confrontation. Their strategic interaction and mutual weapons build‐up has recently attracted the attention of researchers in the field testing the hypothesis of a Greek‐Turkish arms race with conflicting results. This paper, using cointegration and causality tests, finds evidence of a systematic armaments competition between the two countries provided that a defence policy regime shift estimated to occur in 1985 is explicitly taken into consideration. This policy regime change is associated with the stagnation of defence spending in Greece owing to the gradual deterioration of Greek public finances over the last decade.  相似文献   
247.

This paper analyses the convergence between countries in relation to the catch-up hypothesis concerning the level of total productivity. The catch-up hypothesis claims that poor countries tend to grow faster than rich countries through the international diffusion of knowledge and technology. We test this hypothesis for the Balkan countries and investigate the effect of military expenditure in the region on productivity growth. The aim is to investigate empirically whether productivity growth has been greater in countries with lower military expenditure, in line with theory. The results obtained show that, overall, improvements in technological change co-exist with deteriorating technical efficiency change and that there is a negative correlation between military expenditure and either total productivity growth and technological change, and a positive, but statistically insignificant, relationship with technical efficiency change. We conclude that economic growth is the key to regional development and that too great a diversion of resources to military commitments can lead to overstretch.  相似文献   
248.

After a decade of successful recruiting, the US military began experiencing recruiting difficulties in the 1990s. Cyclical factors as well as trend factors may have played a role. This paper uses monthly data by state over the period 1989-1997 to estimate models of enlistment and evaluate the various explanations for the recruiting slowdown. Estimates of the impact of economic variables - relative military pay and unemployment - and recruiting resource variables - recruiters and advertising - are similar to those in previous studies. Two trend factors, rising college attendance and declining adult veteran population (influencers), are found to be important factors explaining the decline in enlistment.  相似文献   
249.

Using a data set of historical battles from 1600 to 1973, this paper analyzes the empirical determinants of tactical success in modern war. Based on a reduced form approach we consider key elements of military theory as production factors for combat success as an output of a military production function. The paper focuses on the relationship of material and non-material factors to battlefield success, and especially on the role of superior force strengths. Contrary to the emphasis on technology which can be found in the recent literature, our estimation results indicate that numerical superiority has retained its crucial role for battlefield performance throughout history. In general, human elements of warfare, like leadership, morale and surprise, have continued to be important determinants of battle outcome despite technological progress in weapons.  相似文献   
250.

The US Air Force is asking when to replace its aging aircraft. We develop a framework to identify economically optimal replacement strategies that recognizes cost trade-offs and incorporates age effects. We also preview a stochastic methodology. We use the framework to identify an optimal strategy, defined by the replacement age, for a generic fleet and conduct a sensitivity analysis. Quantitative illustrations show that the range of strategies that provides close-to-optimal outcomes widens as the operating and support (O&S) cost growth rate decreases and the ratio of the acquisition price to the initial O&S cost increases. A wider range implies more decision-making leeway.  相似文献   
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