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241.
In 1999, rebels rose to oppose the newly elected former warlord Charles Taylor in Liberia. Motivated by a variety of reasons, the minimal common denominator of these rebels, who assumed the name Liberians United for Reconciliation and Democracy (LURD), was that Charles Taylor must leave the country. The decentralized nature of LURD though stands out in their struggle, as they don't fit the unitary actor assumed by literature on strategy, nor the alternative conception of decentralized forces fighting for purely local reasons. Understanding such aberrations as LURD is the first step to finding strategies that can incorporate and manage them.  相似文献   
242.
In this article, we study generalizations of some of the inventory models with nonlinear costs considered by Rosling in (Oper. Res. 50 (2002) 797–809). In particular, we extend the study of both the periodic review and the compound renewal demand processes from a constant lead time to a random lead time. We find that the quasiconvexity properties of the cost function (and therefore the existence of optimal (s, S) policies), holds true when the lead time has suitable log‐concavity properties. The results are derived by structural properties of renewal delayed processes stopped at an independent random time and by the study of log‐concavity properties of compound distributions. © 2015 Wiley Periodicals, Inc. Naval Research Logistics 62: 345–356, 2015  相似文献   
243.
The issue that this paper tackles is the assessment of the relative security benefits that Cyprus and Greece derive in the context of their cooperation on defence matters. This form of cooperation, known as the ‘Integrated Defence Space Doctrine’, aims at defending their interests in the Aegean Sea and the broader East Mediterranean theatre. The paper relies heavily on earlier research on this topic, which deals with the Greek–Cypriot alliance facing an arms race against Turkey, and uses a coefficient especially designed to assess the optimal levels of security and the associated defence expenditure of the two allies. A comparison of the relative security coefficient values for the two allies suggests that the security benefit that Greece derives thanks to its alliance with Cyprus exceeds the corresponding Cypriot benefit by far. Given the importance assigned to human resources by this index, in conjunction with the demographic problems of Greece, this conclusion justifies the recent Greek defence policy revision, emphasizing quality, capital equipment and flexibility of forces. This revision aims at satisfying the security requirements of the alliance and the increasing demands of an arms race against Turkey.  相似文献   
244.
Defence expenditures have both costs and benefits to the economy. The costs of defence expenditures are mainly emphasized as opportunity costs. On the other hand, defence spending may have growth‐promoting potential benefits: a rise in defence spending may result in a higher aggregate demand, production and employment. This paper examines empirically the effects of military expenditures on economic growth for Middle Eastern countries and Turkey, for the time‐period 1989–1999. The relationship between military expenditure and economic growth is investigated by using cross‐section and dynamic panel estimation techniques. Empirical analysis indicates that military expenditure enhances economic growth in the Middle Eastern countries and Turkey as a whole.  相似文献   
245.
This paper investigates the determinants of provincial terrorism in Turkey taking spatial dimension into account for the time period 1990–2006. Following a traditional global regression analysis, spatial variations in the relationships are examined with geographically weighted regression (GWR) to obtain locally different parameter estimates. Empirical results indicate that increases in income and schooling ratio tend to reduce the provincial average level of terrorism, whereas an increase in unemployment enhances it. Moreover, GWR results indicate that the provincial effects of per capita income and education are more pronounced for the Eastern and South Eastern provinces compared to the Western provinces.  相似文献   
246.
CONTRIBUTORS     
Russia holds the largest stocks of civilian highly enriched uranium (HEU) of any country, operating more than fifty research reactors, pulsed reactors, and critical assemblies using HEU, as well as nine HEU-fueled icebreakers. Russia's participation in international efforts to phase out civilian HEU is crucial if international HEU minimization efforts are to succeed. Individual Russian institutes and organizations participate in international programs to replace HEU with low-enriched uranium in Soviet-supplied research reactors, develop alternative fuels, and repatriate fresh and spent HEU fuel from third countries. However, an overarching national policy on HEU phase-out has yet to be adopted. There are many obstacles to obtaining such a commitment from Moscow. At the same time, the ongoing reform of the Russian nuclear industry and plans for expansion of domestic nuclear power generation and for increased nuclear exports create opportunities for securing such a commitment.  相似文献   
247.
The Biological Weapons Convention (BWC) regime currently suffers from a lack of effective compliance procedures. Because a legally binding compliance protocol to the BWC is not available, other measures are needed to stabilize the regime against the risk of violations of its rules. The Treaty on the Non-Proliferation of Nuclear Weapons, the Chemical Weapons Convention, and the experiences of UN inspection teams show that among the necessary components of effective compliance mechanisms are an intermediary level between bilateral consultations of states parties and involvement of the UN Security Council as well as independent assessment capabilities. This article suggests that the UN Secretary General could assume such an intermediary function and, using the authority contained in Article 99 of the UN Charter, could investigate not only alleged use of biological weapons but also alleged breaches of the BWC. A standing expert unit in the Department for Disarmament Affairs could provide the independent expertise necessary for such investigations. Such a compliance mechanism could provisionally help stabilize the BWC regime until a permanent compliance system can be agreed.  相似文献   
248.
This article introduces the twin robots scheduling problem (TRSP), in which two robots positioned at the opposite ends of a rail are required to deliver items to positions along the rail, and the objective is to minimize the makespan. A proof of ‐hardness of the TRSP is presented, along with exact and heuristic algorithms. Computational results on challenging instances are provided.Copyright © 2014 Wiley Periodicals, Inc. Naval Research Logistics 61: 119–130, 2014  相似文献   
249.
Piracy in international waters is on the rise again, in particular off the coast of Somalia. While the dynamic game between pirates, ship-owners, insurance firms and the military seems to have reached some kind of equilibrium, piracy risks generating significant negative externalities to third parties (e.g. in terms of environmental hazards and terrorism), justifying attempts to contain it. We argue that these attempts may benefit from a look back – through the analytical lens of rational choice theory – to the most successful counterpiracy campaign ever undertaken, namely, the one led by the Roman general Gnaeus Pompeius Magnus (Pompey the Great) in 67 BC.  相似文献   
250.
针对仿真中空地导弹攻击复杂目标的毁伤评估问题,提出了一种基于串并联结构分解的目标毁伤评估算法,并引入了修复时间作为毁伤评估的一项指标.该算法首先按结构布局和功能关系将目标分解成多个子系统,并组成串并联结构图,然后根据导弹的精确落点对每个子系统进行毁伤评估,最后综合所有子系统的毁伤情况得出目标整体的毁伤程度和恢复正常所需...  相似文献   
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