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221.
This paper develops and implements a methodology for quantifying defense conversion in Russian manufacturing in the early 1990s. A two‐sector, three‐good model is employed to analyze the flows of resources from military to non‐military uses and applied to firm‐level survey data under alternative definitions of military production and the MIC. An aggregation framework is constructed to estimate the total quantity and change in Russian military production, the latter decomposed into intrafirm and intersectoral resource reallocation and overall industrial decline. Although there is evidence of substantial decline in military production, the data show little reallocation to productive civilian uses, neither within the MIC nor to other manufacturing sectors.  相似文献   
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Machine maintenance is modeled in the setting of a single‐server queue. Machine deterioration corresponds to slower service rates and failure. This leads to higher congestion and an increase in customer holding costs. The decision‐maker decides when to perform maintenance, which may be done pre‐emptively; before catastrophic failures. Similar to classic maintenance control models, the information available to the decision‐maker includes the state of the server. Unlike classic models, the information also includes the number of customers in queue. Considered are both a repair model and a replacement model. In the repair model, with random replacement times, fixed costs are assumed to be constant in the server state. In the replacement model, both constant and variable fixed costs are considered. It is shown in general that the optimal maintenance policies have switching curve structure that is monotone in the server state. However, the switching curve policies for the repair model are not always monotone in the number of customers in the queue. Numerical examples and two heuristics are also presented. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2007  相似文献   
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We derive sufficient conditions which, when satisfied, guarantee that an optimal solution for a single‐machine scheduling problem is also optimal for the corresponding proportionate flow shop scheduling problem. We then utilize these sufficient conditions to show the solvability in polynomial time of numerous proportionate flow shop scheduling problems with fixed job processing times, position‐dependent job processing times, controllable job processing times, and also problems with job rejection. © 2015 Wiley Periodicals, Inc. Naval Research Logistics 62: 595–603, 2015  相似文献   
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Nicholas John Spykman was probably America’s finest geopolitical theorist of the twentieth century, even though he was an active participant over the course only of five years (1938–43). He is rightly viewed as a worthy intellectual successor to Sir Halford Mackinder in Britain. Spykman originated the (Eurasian) Rimland concept, which is of continuing political and strategic utility today. He was controversial and notably outspoken while his writings make it quite clear that his concern with the acquisition of power was contextualised by serious concerns for world order.  相似文献   
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It is generally recognized that the first model involving job scheduling was presented by Selmer Johnson and published in the inaugural issue of Naval Research Logistics Quarterly (NRLQ) in 1954. NRLQ also published another seminal scheduling paper by Wayne E. Smith a short time later. In the present paper, we discuss the contribution of NRLQ and the role of the Office of Naval Research in the development of the scheduling literature during the first decade (1954–1963). We also provide a critical analysis of the papers by Johnson and Smith. © 2015 Wiley Periodicals, Inc. Naval Research Logistics 62: 335–344, 2015  相似文献   
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Jan Sändig 《Civil Wars》2015,17(2):141-160
Why do some protest movements erupt into rebellion, whereas others protest peacefully under similar circumstances? Addressing this question, this paper investigates the cases of Boko Haram (rebellion) and MASSOB (non-violent protest) in contemporary Nigeria. Conventional explanations of rebellion focusing on opportunity, inequality, and repression cannot explain why these movements have pursued different protest strategies. This paper tries to explain this puzzle by investigating the signifying work and meaning construction of both movements drawing on the framing approach from social movement studies. The framing analysis shows that the different protest behavior largely results from the differing cultural context of both movements, from the agency of the framers, and from successful frame alignment, which results in frame resonance and, thereby, the successful mobilization for collective action.  相似文献   
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