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81.
This article explores the phenomenon of herdsmen militancy as a new trajectory for the farmer–herder crisis in Nigeria, with reference to its humanitarian implications. Relying on a systematic analysis of secondary data and aligning with the analytical anchorage of liberal political ecology theory, the article posits that herdsmen militancy depicts a contradiction in agrarian relations in the context of a national security crisis which has been complicated by salient socio-ecological factors such as climate change, armed violence, and identity politics. In view of the dire humanitarian consequences of this situation, the article submits that herdsmen militancy constitutes a major threat to human and national security in Nigeria. It makes a case for a pragmatic policy capable of mitigating the myriad socio-ecological factors that tend to trigger herdsmen militancy, with prohibition on open grazing in critical hotbeds of herder–farmer conflict as a strategic measure.  相似文献   
82.
Two new algorithms are presented for solving linear programs which employ the opposite-sign property defined for a set of vectors in m space. The first algorithm begins with a strictly positive feasible solution and purifies it to a basic feasible solution having objective function value no less under maximization. If this solution is not optimal, then it is drawn back into the interior with the same objective function value, and a restart begins. The second algorithm can begin with any arbitrary feasible point. If necessary this point is purified to a basic feasible solution by dual-feasibility–seeking directions. Should dual feasibility be attained, then a duality value interval is available for estimating the unknown objective function value. If at this juncture the working basis is not primal feasible, then further purification steps are taken tending to increase the current objective function value, while simultaneously seeking another dual feasible solution. Both algorithms terminate with an optimal basic solution in a finite number of steps.  相似文献   
83.
In 2014, Colonel M. Shane Riza published an article in this journal arguing that remotely piloted aircraft (RPA) and robotic weapons threaten the US Air Force’s warrior ethos. Riza has clearly articulated the sentiments of one side of a vibrant debate within our service. This paper presents an alternative view; a view held by some who have experienced these new forms and tools of war, and who have wrestled with their implications first-hand. In this paper, we address some methodological concerns with Riza’s approach and then engage some misunderstandings about RPA’s relationship to military history and to risk. The second part of this paper takes a close look at some of the early Just War thinkers to determine what implications the tradition may have on the warrior ethos. We propose, as an alternative to Riza’s position, a return to an ethos grounded in humility, charity, and a conception of war as a last resort; in short, a return to the Just Warrior Ethos.  相似文献   
84.
85.
In this paper we investigate the collection depots location problem on a network. A facility needs to be located to serve a set of customers. Each service consists of a trip to the customer, collecting materials, dropping the materials at one of the available collection depots and returning to the facility to wait for the next call. Two objectives are considered: minimizing the weighted sum of distances and minimizing the maximum distance. The properties of the solutions to these problems are described. © 2002 John Wiley & Sons, Inc. Naval Research Logistics, 49: 15–24, 2002; DOI 10.1002/nav.10000  相似文献   
86.
In this article we develop a class of general knapsack problems which are hard for branch and bound algorithms. The number of alternate optimal solutions for these problems grows exponentially with problem parameters. In addition the LP bound is shown to be ineffective. Computational tests indicate that these problems are truly difficult for even very small problems. Implications for the testing of algorithms using randomly generated problems is discussed.  相似文献   
87.
88.
This article shows under which circumstances fraudulent accreditation can occur in Brazilian military hospitals, calling attention to the tone at the top as a critical aspect of military fraud deterrence – and hence as a critical aspect of this branch of military ethics. The problems allegedly found in Brazilian military health institutions were revealed through in-depth interviews conducted with 29 professionals who reported to work or have worked in a Brazilian military hospital. These fraud allegations were mostly associated with false documentation and procedures designed to give the appearance that legal requirements for accreditation were met and could be traced back to a weak or corrupt “tone at the top” coming from military higher ranks.  相似文献   
89.
We present a branch‐and‐price technique for optimal staff scheduling with multiple rest breaks, meal break, and break windows. We devise and implement specialized branching rules suitable for solving the set covering type formulation implicitly, using column generation. Our methodology is more widely applicable and computationally superior to the alternative methods in the literature. We tested our methodology on 365 test problems involving between 1728 and 86400 shift variations, and 20 demand patterns. In a direct comparison with an alternative method, our approach yields significant improvements both in cpu time and in the number of problem instances solved to optimality. The improvements were particularly marked for problems involving larger numbers of feasible shifts. © 2000 John Wiley & Sons, Inc. Naval Research Logistics 47: 185–200, 2000  相似文献   
90.
Consider n jobs (J1, …, Jn), m working stations (M1, …, Mm) and λ linear resources (R1, …, Rλ). Job Ji consists of m operations (Oi1, …, Oim). Operation Oij requires Pk(i, j) units of resource Rk to be realized in an Mj. The availability of resource Rk and the ability of the working station Mh to consume resource Rk, vary over time. An operation involving more than one resource consumes them in constant proportions equal to those in which they are required. The order in which operations are realized is immaterial. We seek an allocation of the resources such that the schedule length is minimized. In this paper, polynomial algorithms are developed for several problems, while NP-hardness is demonstrated for several others. © 1998 John Wiley & Sons, Inc. Naval Research Logistics 45: 51–66, 1998  相似文献   
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