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331.
This article presents a flexible days‐on and days‐off scheduling problem and develops an exact branch and price (B&P) algorithm to find solutions. The main objective is to minimize the size of the total workforce required to cover time‐varying demand over a planning horizon that may extend up to 12 weeks. A new aspect of the problem is the general restriction that the number of consecutive days on and the number of consecutive days off must each fall within a predefined range. Moreover, the total assignment of working days in the planning horizon cannot exceed some maximum value. In the B&P framework, the master problem is stated as a set covering‐type problem whose columns are generated iteratively by solving one of three different subproblems. The first is an implicit model, the second is a resource constrained shortest path problem, and the third is a dynamic program. Computational experiments using both real‐word and randomly generated data show that workforce reductions up to 66% are possible with highly flexible days‐on and days‐off patterns. When evaluating the performance of the three subproblems, it was found that each yielded equivalent solutions but the dynamic program proved to be significantly more efficient. © 2013 Wiley Periodicals, Inc. Naval Research Logistics 60: 678–701, 2013  相似文献   
332.
毛泽东早在20世纪50年代,就开始对适合中国国情的社会主义建设道路进行了一系列开创性探索。他基于中国经济文化落后的基本现状,对“什么是社会主义”、“如何建设和发展社会主义”等问题进行了艰苦探索,并提出许多富有创造性的思想。毛泽东探索的过程是极其艰辛的,其中既有成功的经验,也有失败的教训。今天总结这些经验教训,对于我们更好地坚持和发展中国特色社会主义,具有重大的历史意义和现实意义,同时这也是坚持贯彻习近平“两个不能否定”的基本要求。  相似文献   
333.
Australia is a geographically large country, with the world's longest national coastline to defend, but a relatively small economy of some 17.5 million people. Since World War II, Australia has faced the dilemma of how to structure defence policy in the absence of an identifiable threat. Its policy of self‐reliance aims to permit Australia to conduct defensive operations in the event of low/medium level threats without depending immediately on its allies. This is to be achieved through the technological sophistication of defence equipment, a highly professional but small defence force and local industry support.

The burden of defence, measured as the share of defence outlay in GDP declined from about 3% in 1971–72 to about 2.3% in 1993–94. It has been the Government's policy to encourage the development of local defence‐related industry, in particular in areas such as: electronics/optics; communications and information technology; aerospace; shipbuilding and repair, munitions; and land vehicles. However, defence procurement has a small impact on the Australian economy as a whole.  相似文献   
334.
This survey article focuses on defence economics issues and provides data and analysis on the Federal Republic of Yugoslavia's (FRY) defence policy, defence spending, the size of its armed forces, its defence industries and the cost of the civil war. The main section is devoted to the period from 1990 to the present and deals with the following aspects: the situation after the break‐up of the former Yugoslavia, general economic data; the cost of the civil war, the defence budget; the armed forces; the manufacture of armaments and the structure of the defence industry.  相似文献   
335.
This article identifies and evaluates likely challenges facing NATO today and into the next millennium. These contingencies include ethnic‐based civil wars in Europe, transnational terrorism, rogue states, increased world income inequality, out‐of‐area conflicts, and environmental and resource security. Using concepts and tools from collective action, I assess these challenges and suggest effective policies for addressing them. NATO still has a crucial role to play in maintaining world security in the post‐Cold War era.  相似文献   
336.
This paper presents a simple model to characterize explicitly the role that an intervening third party plays in raising the cost of rebellion in an intrastate conflict. Extending the Gershenson‐Grossman (2000 Gershenson, D. and Grossman, H.I. 2000. Civil conflict: ended or never ending?. Journal of Conflict Resolution, 44(6): 807821.  [Google Scholar]) framework of conflict in a two‐stage game to the case involving outside intervention in a three‐stage game as in Chang et al. (2007b Chang, Y.‐M., Potter, J. and Sanders, S. 2007b. War and peace: third‐party intervention in conflict. European Journal of Political Economy, 23(4): 954974.  [Google Scholar]), we examine the conditions under which an outside party optimally intervenes such that (i) the strength of the rebel group is diminished or (ii) the rebellion is deterred altogether. We also find conditions in which a third party optimally intervenes but at a level insufficient to deter rebellion. Such behavior, which improves the incumbent government’s potential to succeed in conflict, is overlooked in some conflict studies evaluating the effectiveness of intervention. One policy implication of the model is that an increase in the strength of inter‐governmental trade partnerships increases the likelihood that third‐party intervention deters rebellion.  相似文献   
337.
An availability‐oriented approach has been developed to decide when to replace an aging system. For an existing system, it is optimal to operate another year if and only if the incremental cost per available year is less than the lifetime average cost per available year of a new aircraft. We illustrate our approach using United States Air Force KC‐135 tanker data. In demonstrating our approach, we find it will be optimal to replace the KC‐135 by the end of the decade.  相似文献   
338.
This paper analyses the long‐run demand for defence output through a homogeneous treatment of 15 NATO member countries between 1960 and 1999. We carry out a progressive study of the interactions between either defence spending or defence burden and their main determinants: income, external threat and allied military spending. To that end, we use time‐series analysis with endogenously determined structural breaks. We further consider individual country functions related to one another through a common correlated effects method, in order to take into account explicitly the connections between members of an alliance.  相似文献   
339.
This study analyses an arms race between South and North Korea over the period 1963–2000. Despite the strategic importance of the Korean Peninsula, the arms race between South and North Korea has rarely been studied. In this study, the South–North arms race is empirically estimated using Richardson’s action–reaction model. The pattern of South–North arms race between the Cold War (1963–1989) and the post‐Cold War eras (1990–2000) as well as the existence of an arms race is examined comparing both countries’ defence spending, number of military personnel and tactical aircraft.  相似文献   
340.
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