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31.
This essay traces the image of Germany that emerges from the reports of Colonel Frederick Trench (1857–1942), British military attache in Berlin from 1906 to 1910. At this time, the British Army possessed only the most limited intelligence‐gathering apparatus and had to rely heavily on the reports of military attaches for information about their continental rivals. Trench, who believed that Germany planned to wage war against Britain and said so categorically in his reports, was the main source of data on the German Army. From the limited surviving records of who read these reports and how they responded to them, this essay posits that Trench's views contributed to the growing British perception of a German threat, a perception that did much to influence British strategic planning in this period.  相似文献   
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Defusing Armageddon: Inside NEST, America's Secret Nuclear Bomb Squad, by Jeffrey T. Richelson. W.W. Norton & Company, 2009. 318 pages, $27.95.  相似文献   
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In 2011, the Department for International Development, the Foreign & Commonwealth Office, and the Ministry of Defence launched the Building Stability Overseas Strategy (BSOS). This document sought to integrate cross-government activity as it related to conflict and security so as to ‘take fast, appropriate and effective action to prevent a crisis or stop it escalating and spreading’. At the heart of the strategy was the recognition that addressing instability and conflict overseas was morally right and in the UK's national interests. This confluence of foreign policy realism and ethical outlook most clearly found harmony in the acknowledgement that it was cheaper for the international community to avoid conflict than it was to try to manage it. Through an examination of three historical case studies (Uganda 1964–1972, Rhodesia–Zimbabwe 1979–1981, and Sierra Leone 2000–2007), this article seeks to demonstrate just how difficult this seemingly sensible strategic outlook is. In particular, the article shows there are historical parallels in British postcolonial history that very closely resemble contemporary policy choices; that these can be used to define what is different about past and present practice; and, which in turn, can be used to – at least tentatively – mark out the potential strengths and weaknesses in BSOS.  相似文献   
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We develop models that lend insight into how to design systems that enjoy economies of scale in their operating costs, when those systems will subsequently face disruptions from accidents, acts of nature, or an intentional attack from a well‐informed attacker. The systems are modeled as parallel M/M/1 queues, and the key question is how to allocate service capacity among the queues to make the system resilient to worst‐case disruptions. We formulate this problem as a three‐level sequential game of perfect information between a defender and a hypothetical attacker. The optimal allocation of service capacity to queues depends on the type of attack one is facing. We distinguish between deterministic incremental attacks, where some, but not all, of the capacity of each attacked queue is knocked out, and zero‐one random‐outcome (ZORO) attacks, where the outcome is random and either all capacity at an attacked queue is knocked out or none is. There are differences in the way one should design systems in the face of incremental or ZORO attacks. For incremental attacks it is best to concentrate capacity. For ZORO attacks the optimal allocation is more complex, typically, but not always, involving spreading the service capacity out somewhat among the servers. © 2011 Wiley Periodicals, Inc. Naval Research Logistics, 2011  相似文献   
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Like airlines and hotels, sports teams and entertainment venues can benefit from revenue management efforts for their ticket sales. Teams and entertainment venues usually offer bundles of tickets early in their selling horizon and put single‐event tickets on sale at a later date; these organizations must determine the best time to offer individual tickets because both types of ticket sales consume the same fixed inventory. We model the optimal a priori timing decision for a seller with a fixed number of identical tickets to switch from selling the tickets as fixed bundles to individual tickets to maximize the revenue realized before the start of the performance season. We assume that bundle and single‐ticket customers each arrive according to independent, nonhomogeneous Markovian death processes with a linear death rate that can vary over time and that the benefit from selling a ticket in a package is higher than from selling the ticket individually. We characterize the circumstances in which it is optimal for the seller to practice mixed bundling and when the seller should only sell bundles or individual tickets, and we establish comparative statics for the optimal timing decision for the special case of constant customer arrival rates. We extend our analytical results to find the optimal time for offering two groups of tickets with high and low demand. Finally, we apply the timing model to a data set obtained from the sports industry. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2008  相似文献   
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In this study, we illustrate a real‐time approximate dynamic programming (RTADP) method for solving multistage capacity decision problems in a stochastic manufacturing environment, by using an exemplary three‐stage manufacturing system with recycle. The system is a moderate size queuing network, which experiences stochastic variations in demand and product yield. The dynamic capacity decision problem is formulated as a Markov decision process (MDP). The proposed RTADP method starts with a set of heuristics and learns a superior quality solution by interacting with the stochastic system via simulation. The curse‐of‐dimensionality associated with DP methods is alleviated by the adoption of several notions including “evolving set of relevant states,” for which the value function table is built and updated, “adaptive action set” for keeping track of attractive action candidates, and “nonparametric k nearest neighbor averager” for value function approximation. The performance of the learned solution is evaluated against (1) an “ideal” solution derived using a mixed integer programming (MIP) formulation, which assumes full knowledge of future realized values of the stochastic variables (2) a myopic heuristic solution, and (3) a sample path based rolling horizon MIP solution. The policy learned through the RTADP method turned out to be superior to polices of 2 and 3. © 2010 Wiley Periodicals, Inc. Naval Research Logistics 2010  相似文献   
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Customers served by an M/M/1 queueing system each receive a reward R but pay a holding cost of C per unit time (including service time) spent in the system. The decision of whether or not a customer joins the queue can be made on an individual basis or a social basis. The effect of increasing the arrival rate on the optimal policy parameters is examined. Some limiting results are also derived.  相似文献   
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A range of theories have sought to explain and predict secession with varying degrees of success. Arguing that a disproportionate focus upon the seceding group as the unit of analysis has frustrated the development of a comprehensive theoretical framework that is universally valid, this article highlights the role of predecessor institutions of governance and the failure of states to successfully incorporate these as an important, but neglected, causal factor in the study of secession. The inclusion of pre-state institutions of governance and processes of state formation not only results in a more complete, and therefore accurate, explanatory account of secession, but also explains why some regions have been more prone to secession than others.  相似文献   
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