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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   
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Recent counterinsurgency experiences in Iraq and Afghanistan have demonstrated that the local operating environment often is dominated by indigenous power-holders. As counterinsurgents seek to establish control over the local population, collaboration with these agents has become an essential aspect of contemporary counterinsurgency. Although the practice of constructing collaborative relationships with indigenous power-holders might be perceived as unconventional by today's counterinsurgents, the approach itself goes back to the colonial era in which modern counterinsurgency has its roots. This article explores the dynamics, benefits, and dangers of collaborative relationships with indigenous power-holders by analysing an infamous episode in Dutch colonial history, the case of the collaboration between Dutch colonial authorities and warlord Teuku Uma during the Aceh War (1873–1913). This relationship ended in disaster for the Dutch as Uma departed their side at the moment he had become their pivotal asset in the local political landscape. The article explains that the Dutch succeeded to co-opt Uma, but failed to control him as they lacked the will and means to do so. Furthermore this case study provides an insight in the way the Dutch colonial authorities dealt with the complex process of intelligence-gathering in a fragmented indigenous society.  相似文献   
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Casualty figures suggest that the US/Allied Counter Improvised Explosive Device (C-IED) policy and the present allocation of national assets, resources, and intellectual capital have not been very successful. A number of explanations for why this has been the case are discussed and critiqued here.  相似文献   
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ABSTRACT

Research concerning authoritarian stability and peace usually investigates co-optation and repression. Recently, several studies argue that traditional legitimacy is also important for stability in monarchies. However, existing research rarely considers how legitimacy constrains rebellions and help the royal family to stay in power. Hence, this article explores the causal links between sources of traditional legitimacy and absence of uprisings. The study investigates the relationship with a case study of the Kingdom of Swaziland. In line with my expectations, I find a causal relationship between sources of traditional legitimacy and absence of popular uprisings. First, the royal family actively uses traditional legitimacy to justify their rule. Second, the Afrobarometer indicates that the Swazi people trust the King more than citizens in other African countries trust their head of state. Third, opposition actors have limited opportunities to mobilize the broader population against the monarchy. Fourth, traditional legitimacy dampens ongoing protests and thereby hinders their escalation into popular uprisings or political violence. Repression is clearly an important explanation for limited rebellion in Swaziland, but this article shows that also traditional legitimacy sources play a role.  相似文献   
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