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391.
Canada is now at a crossroads unlike any other period in its history and needs to carefully consider which path to take. With the new Trudeau government comfortably ensconced since the defeat of the Harper government in the fall of 2015, a variety of competing interests have emerged in an attempt to turn Canadian policy back to a more nostalgic period of the 1970s that some see as preferable to the institutional lash-up that existed since the rolling out of the Canada First policy in the 2000s. That nostalgic period is, however, misunderstood both willfully for political purposes but also through a lack of historical context. Firmly rooting future actions in a blunt analysis of national interests is preferable to the alternative.  相似文献   
392.
The literature on how European states have adapted to the post-cold war security environment ffocuses invariably on different understandings of military transformation, a process which is seen as inherently different from other forms of organizational change. However, as this paper argues, new management practices, going back to the introduction of so-called New Public Management (NPM) reforms throughout Europe in the 1980s, have eventually penetrated also the last bastion of the old state – the defense sector. Taking a critical approach to the idea of military transformation and existing theories of military change, the paper demonstrates how other international developments have pushed towards what may be seen as a “normalization” of Europe’s defense sectors. This has important implications for how we approach and understand change in contemporary defense organizations.  相似文献   
393.
Security strategies are important sites for narrating the EU into existence as a security actor. The unveiling of a new global strategy on foreign and security policy for the EU immediately post-Brexit could be conceived as a pledge to remain together as a Union for the purposes of contributing to global security in a particular way. This paper offers a brief stock-taking of the EU’s way of writing security from the European Security Strategy (2003) to the EU Global Strategy (2016). A concise exegesis of these documents exposes an interesting dynamic: as exercises in ordering the world, both strategic guidelines have turned out to be major exercises in ordering the self. The comparative snapshot shows the EU as increasingly anxious to prove its relevance for its own citizens, yet notably less confident about its actual convincingness as an ontological security framework for the EU’s constituent members over time.  相似文献   
394.
395.
Traditional inventory systems treat all demands of a given item equally. This approach is optimal if the penalty costs of all customers are the same, but it is not optimal if the penalty costs are different for different customer classes. Then, demands of customers with high penalty costs must be filled before demands of customers with low penalty costs. A commonly used inventory policy for dealing with demands with different penalty costs is the critical level inventory policy. Under this policy demands with low penalty costs are filled as long as inventory is above a certain critical level. If the inventory reaches the critical level, only demands with high penalty costs are filled and demands with low penalty costs are backordered. In this article, we consider a critical level policy for a periodic review inventory system with two demand classes. Because traditional approaches cannot be used to find the optimal parameters of the policy, we use a multidimensional Markov chain to model the inventory system. We use a sample path approach to prove several properties of this inventory system. Although the cost function is not convex, we can build on these properties to develop an optimization approach that finds the optimal solution. We also present some numerical results. © 2008 Wiley Periodicals, Inc. Naval Research Logistics, 2008  相似文献   
396.
We consider the problem of determining the capacity to assign to each arc in a given network, subject to uncertainty in the supply and/or demand of each node. This design problem underlies many real‐world applications, such as the design of power transmission and telecommunications networks. We first consider the case where a set of supply/demand scenarios are provided, and we must determine the minimum‐cost set of arc capacities such that a feasible flow exists for each scenario. We briefly review existing theoretical approaches to solving this problem and explore implementation strategies to reduce run times. With this as a foundation, our primary focus is on a chance‐constrained version of the problem in which α% of the scenarios must be feasible under the chosen capacity, where α is a user‐defined parameter and the specific scenarios to be satisfied are not predetermined. We describe an algorithm which utilizes a separation routine for identifying violated cut‐sets which can solve the problem to optimality, and we present computational results. We also present a novel greedy algorithm, our primary contribution, which can be used to solve for a high quality heuristic solution. We present computational analysis to evaluate the performance of our proposed approaches. © 2016 Wiley Periodicals, Inc. Naval Research Logistics 63: 236–246, 2016  相似文献   
397.
The debate over whether there exists a British counter-insurgency tradition of minimum force is one that has been thoroughly discussed. Is there anything left to say? This study suggests there is further insight to be attained if one explicitly evaluates the concept of minimum force in relation to the conduct of the security forces in the years of the Northern Ireland conflict. Through an examination of three key periods in the conflict, it will be shown that while there was invariably an awareness of the need to act with restraint among senior officers at the strategic level, this was often difficult to apply at the tactical level in the heat of confrontation. The argument demonstrates that the British Army, and other instruments of the state, rarely acted in a manner that could be described as ‘minimal’. Instead, it was the broader liberal values of the British state that explains largely the degrees of restraint exhibited by the government and security forces.  相似文献   
398.
An efficient algorithm for determining the optimal arrival schedule for customers in a stochastic service system is developed. All customers arrive exactly when scheduled, and service times are modeled as iid Erlang random variables. Costs are incurred at a fixed rate per unit of time each customer waits for service, and an additional cost is incurred for every unit of time the server operates beyond a scheduled closing time. The objective is to minimize total operating cost. This type of problem arises in many operational contexts including transportation, manufacturing, and appointment‐based services. © 1999 John Wiley & Sons, Inc. Naval Research Logistics 46: 549–559, 1999  相似文献   
399.
The paper considers the open shop scheduling problem to minimize the make-span, provided that one of the machines has to process the jobs according to a given sequence. We show that in the preemptive case the problem is polynomially solvable for an arbitrary number of machines. If preemption is not allowed, the problem is NP-hard in the strong sense if the number of machines is variable, and is NP-hard in the ordinary sense in the case of two machines. For the latter case we give a heuristic algorithm that runs in linear time and produces a schedule with the makespan that is at most 5/4 times the optimal value. We also show that the two-machine problem in the nonpreemptive case is solvable in pseudopolynomial time by a dynamic programming algorithm, and that the algorithm can be converted into a fully polynomial approximation scheme. © 1998 John Wiley & Sons, Inc. Naval Research Logistics 45: 705–731, 1998  相似文献   
400.
Iran’s support for terrorist groups is the subject of countless articles and monographs. Less emphasis is placed on Tehran’s efforts to fight terrorist groups targeting the Iranian state. Yet, modern domestic and foreign terrorist groups have targeted Iran for decades. As a result, the country has developed fairly sophisticated, albeit opaque, counterterrorism apparatus and mechanisms. This article sheds light on the Iranian counterterrorism apparatus and efforts since the 1979 Islamic Revolution, drawing on several years of fieldwork in Iran, interviews with current and former officials, and Persian sources.  相似文献   
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