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This article explores the question of why so few insurgencies from the ancient world have ever made it onto the big screen. Many of these stories have been made into documentaries, but have been ignored by Hollywood. Even those events that have been made into Hollywood films, like the uprising of Spartacus, do not show any of the successful uprisings, only the defeats. Among the possible reasons may be Hollywood's fascination with big wars and big battles rather than small wars because they are more cinematic. Another reason is that American movies are reluctant to show successful slave uprisings or insurgencies against great powers. In the end, all movies are about the present, not the past, and thus Western bias will side with the imperial power, not the terrorist.  相似文献   
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This paper presents an application of a method for finding the global solution to a problem in integers with a separable objective function of a very general form. This report shows that there is a relationship between an integer problem with a separable nonlinear objective function and many constraints and a series of nonlinear problems with only a single constraint, each of which can be solved sequentially using dynamic programming. The first solution to any of the individual smaller problems that satisfies the original constraints in addition, will be the optimal solution to the multiply-constrained problem.  相似文献   
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Given a number of patrollers that are required to detect an intruder in a channel, the channel patrol problem consists of determining the periodic trajectories that the patrollers must trace out so as to maximized the probability of detection of the intruder. We formulate this problem as an optimal control problem. We assume that the patrollers' sensors are imperfect and that their motions are subject to turn‐rate constraints, and that the intruder travels straight down a channel with constant speed. Using discretization of time and space, we approximate the optimal control problem with a large‐scale nonlinear programming problem which we solve to obtain an approximately stationary solution and a corresponding optimized trajectory for each patroller. In numerical tests for one, two, and three underwater patrollers, an underwater intruder, different trajectory constraints, several intruder speeds and other specific parameter choices, we obtain new insight—not easily obtained using simply geometric calculations—into efficient patrol trajectory design under certain conditions for multiple patrollers in a narrow channel where interaction between the patrollers is unavoidable due to their limited turn rate.© 2011 Wiley Periodicals, Inc. Naval Research Logistics, 2011  相似文献   
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We formulate and solve a discrete‐time path‐optimization problem where a single searcher, operating in a discretized three‐dimensional airspace, looks for a moving target in a finite set of cells. The searcher is constrained by maximum limits on the consumption of one or more resources such as time, fuel, and risk along any path. We develop a specialized branch‐and‐bound algorithm for this problem that uses several network reduction procedures as well as a new bounding technique based on Lagrangian relaxation and network expansion. The resulting algorithm outperforms a state‐of‐the‐art algorithm for solving time‐constrained problems and also is the first algorithm to solve multi‐constrained problems. © 2010 Wiley Periodicals, Inc. Naval Research Logistics, 2010  相似文献   
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The ‘resource curse’ is the paradoxical theory frequently used to explain how a seemingly desirable asset, such as oil, can actually pervert an economy, erode governance, perpetuate conflict, and ruin local communities to the extent that it becomes a curse. New oil discoveries in western Ghana and western Uganda have raised concerns for the democratic prospects and future stability of these countries and their surrounding regions. Based on field interviews in these oil-producing regions, this report summarises how local communities have been affected thus far and their concerns for the future. The authors assess the extent to which each country is vulnerable to oil-induced instability, and identify groups or communities that would be most likely to perpetuate it. Lastly, it provides some assessment of the future trajectory of each country.  相似文献   
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An algorithm is presented to gain postoptimality data about the family of nonlinear pure integer programming problems in which the objective function and constraints remain the same except for changes in the right-hand side of the constraints. It is possible to solve such families of problems simultaneously to give a global optimum for each problem in the family, with additional problems solved in under 2 CPU seconds. This represents a small fraction of the time necessary to solve each problem individually.  相似文献   
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