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211.
ABSTRACT

There have been calls for the abolition of nuclear weapons from the day they were invented. Over the last fifteen years, some indications can be found that such calls have been getting louder, among them Barack Obama's famous 2009 speech in Prague. In this article, we investigate if support for a comprehensive norm that would prohibit development, possession, and use of nuclear weapons is really growing. To assess the current status of that norm, we use the model of a “norm life cycle,” developed by Martha Finnemore and Kathryn Sikkink. We then analyze 6,545 diplomatic statements from the review process of the Treaty on the Non-Proliferation of Nuclear Weapons as well as from the UN General Assembly First Committee on Disarmament and International Security, covering the years 2000 to 2013. The evidence shows that a comprehensive prohibition can be considered an emerging international norm that finds growing support among states without nuclear weapons and nuclear weapon states alike. Only a core group of states invoke the norm consistently, however. This leads us to conclude that the “tipping point” of the life cycle, at which adherence to a new norm starts to spread rapidly, has yet to be reached.  相似文献   
212.
    
ABSTRACT

The most critical challenges faced by war-affected communities where children have allegedly perpetrated atrocities include: finding transitional justice practices that address the needs of former belligerent children and those of victims and their communities; and helping to reintegrate child soldiers into society and avoid returning to hostilities. This paper demonstrates that these challenges can be overcome by taking a holistic approach to child soldiering transitional justice, which assimilates restorative justice and social justice. Such an approach simultaneously addresses child soldiers’ criminal accountability and pursues their psychosocial wellbeing. The findings are based on a selective scholarship supported by fieldwork that was conducted in the Democratic Republic of Congo between May and December 2014 in North Kivu province. Data was gathered through semi-structured interviews, focus group discussions and survey questionnaires based on a randomised sample of 282 participants. These included self-demobilised child soldiers, members of war-affected communities, students/learners, educators, local traditional leaders, government officials, child protection lawyers and members of non-governmental organisations.  相似文献   
213.
    
The lessons from the two French counterinsurgencies, Indochina and Algeria, give rise to a new understanding of the projection of airpower in remote and hostile environments and the purpose, design, and use of aircraft in counterinsurgency. In both Indochina and Algeria, the campaigns were ones of poverty, and it is their imaginative management under severe resource constraints that provides thoughtful and applicable lessons for today. In both cases, airpower held the promise of delivering victory and solving the resource issue. In Indochina, acquisition of the needed aircraft, operating knowledge, and experience came too slowly to realize this promise. In Algeria, the French embraced the lessons from Indochina and were quite successful and innovative in the use of airpower. The lessons can be reduced to four requirements: (1) a network of airfields for liaison, ground-support, and intra-theater airlift to enable effective air support of ground forces; (2) a solid, reliable, and simple ground-support aircraft capable of operating from forward airfields within range of ground engagements; (3) a capable intra-theater heavy-lift transport to supply the extended ground forces; and (4) helicopter capability to enhance tactical troop mobility and support.  相似文献   
214.
    
Customer acquisition and customer retention are the most important challenges in the increasingly competitive telecommunications industry. Traditional studies of customer switching always assume that customers are homogeneous, and thus that model customer switching behavior follows a Markov formulation. However, this postulation is obviously inappropriate in most instances. Blumen et al. (Cornell Studies of Industrial and Labor Relations, Cornell University Press, Ithaca, NY, 1955) developed the Mover–Stayer (MS) model, a generalization of the Markov chain model, to relax the requirement of homogeneity and allow the presence of heterogeneity with two different types of individuals—“stayers,” who purchase the same kinds of products or services throughout the entire observation period; and “movers,” who look for variety in products or services over time. There are two purpose of this article. First, we extend the MS model to a Double Mover‐Stayer (DMS) model by assuming the existence of three types of individuals in the market: (1) stable and loyal customers, who have stable usage within the same company; (2) instable but loyal customers, whose usage varies within the same company over time; and (3) disloyal customers, who switch from one company to another to seek for new experiences or/and benefits. We also propose an estimation method for the DMS model. Second, we apply the DMS model to telecommunications data and demonstrate how it can be used for pattern identification, hidden knowledge discovery, and decision making. © 2012 Wiley Periodicals, Inc. Naval Research Logistics, 2012  相似文献   
215.
    
We present a group testing model for items characterized by marker random variables. An item is defined to be good (defective) if its marker is below (above) a given threshold. The items can be tested in groups; the goal is to obtain a prespecified number of good items by testing them in optimally sized groups. Besides this group size, the controller has to select a threshold value for the group marker sums, and the target number of groups which by the tests are classified to consist only of good items. These decision variables have to be chosen so as to minimize a cost function, which is a linear combination of the expected number of group tests and an expected penalty for missing the desired number of good items, subject to constraints on the probabilities of misclassifications. We treat two models of this kind: the first one is based on an infinite population size, whereas the second one deals with the case of a finite number of available items. All performance measures are derived in closed form; approximations are also given. Furthermore, we prove monotonicity properties of the components of the objective function and of the constraints. In several examples, we study (i) the dependence of the cost function on the decision variables and (ii) the dependence of the optimal values of the decision variables (group size, group marker threshold, and stopping rule for groups classified as clean) and of the target functionals (optimal expected number of tests, optimal expected penalty, and minimal expected cost) on the system parameters.© 2011 Wiley Periodicals, Inc. Naval Research Logistics, 2011  相似文献   
216.
    
Consider a patrol problem, where a patroller traverses a graph through edges to detect potential attacks at nodes. An attack takes a random amount of time to complete. The patroller takes one time unit to move to and inspect an adjacent node, and will detect an ongoing attack with some probability. If an attack completes before it is detected, a cost is incurred. The attack time distribution, the cost due to a successful attack, and the detection probability all depend on the attack node. The patroller seeks a patrol policy that minimizes the expected cost incurred when, and if, an attack eventually happens. We consider two cases. A random attacker chooses where to attack according to predetermined probabilities, while a strategic attacker chooses where to attack to incur the maximal expected cost. In each case, computing the optimal solution, although possible, quickly becomes intractable for problems of practical sizes. Our main contribution is to develop efficient index policies—based on Lagrangian relaxation methodology, and also on approximate dynamic programming—which typically achieve within 1% of optimality with computation time orders of magnitude less than what is required to compute the optimal policy for problems of practical sizes. © 2014 Wiley Periodicals, Inc. Naval Research Logistics, 61: 557–576, 2014  相似文献   
217.
218.
The military effectiveness literature has largely dismissed the role of material preponderance in favor of strategic interaction theories. The study of counterinsurgency, in which incumbent victory is increasingly rare despite material superiority, has also turned to other strategic dynamics explanations like force employment, leadership, and insurgent/adversary attributes. Challenging these two trends, this paper contends that even in cases of counterinsurgency, material preponderance remains an essential—and at times the most important—factor in explaining battlefield outcomes and effectiveness. To test this, the paper turns to the case of the Sri Lankan state’s fight against the Tamil Tiger insurgency, a conflict which offers rich variation over time across six periods and over 25 years. Drawing on evidence from historical and journalistic accounts, interviews, memoirs, and field research, the paper demonstrates that material preponderance accounts for variation in military effectiveness and campaign outcomes (including military victory in the final campaign) better than strategic explanations. Additionally, a new quantitative data-set assembled on annual loss-exchange ratios demonstrates the superiority of materialist explanations above those of skill, human capital, and regime type.  相似文献   
219.
    
Technologically advanced aircraft rely on robust and responsive logistics systems to ensure a high state of operational readiness. This paper fills a critical gap in the literature for combat models by closely relating effectiveness of the logistics system to determinants of success in combat. We present a stochastic diffusion model of an aerial battle between Blue and Red forces. The number of aircraft of Blue forces aloft and ready to be aloft on combat missions is limited by the maximum number of assigned aircraft, the reliability of aircraft subsystems, and the logistic system's ability to repair and replenish those subsystems. Our parsimonious model can illustrate important trade‐offs between logistics decision variables and operational success.  相似文献   
220.
Since 2012, China’s assertion of its sovereignty claim to the contested Senkaku/Diaoyu Islands has significantly raised the risk of a potentially escalatory political-military crisis with Japan. As circumstances worsen, Japanese Prime Minister Shinzo Abe has championed major institutional reforms aimed at centralizing Japanese security policy decision-making and vastly improving crisis management. This article assesses these reforms’ significance for ameliorating Japan’s long-standing internal crisis management weaknesses, and enhancing its ability to communicate with Beijing promptly under challenging conditions. While significant issues remain, recent developments – especially the establishment of Japan’s first-ever National Security Council – demonstrate significant progress. Bilaterally, however, important firebreaks remain conspicuously absent.  相似文献   
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