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151.
In this paper an inventory model with several demand classes, prioritised according to importance, is analysed. We consider a lot‐for‐lot or (S ? 1, S) inventory model with lost sales. For each demand class there is a critical stock level at and below which demand from that class is not satisfied from stock on hand. In this way stock is retained to meet demand from higher priority demand classes. A set of such critical levels determines the stocking policy. For Poisson demand and a generally distributed lead time, we derive expressions for the service levels for each demand class and the average total cost per unit time. Efficient solution methods for obtaining optimal policies, with and without service level constraints, are presented. Numerical experiments in which the solution methods are tested demonstrate that significant cost reductions can be achieved by distinguishing between demand classes. © 2002 Wiley Periodicals, Inc. Naval Research Logistics 49: 593–610, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/nav.10032  相似文献   
152.
When selling complementary products, manufacturers can often benefit from considering the resulting cross‐market interdependencies. Although using independent retailers makes it difficult to internalize these positive externalities, the ensuing double marginalization can mitigate within‐market competition. We use standard game theoretic analysis to determine optimal distribution channel strategies (through independent retailers or integrated) for competing manufacturers who participate in markets for complements. Our results suggest that a firm's optimal channel choice is highly dependent on its competitive positioning. A firm with a competitive advantage in terms of product characteristics (customer preferences) or production capabilities (cost) might benefit from selling through company‐controlled stores, allowing coordinated pricing across the two markets, whereas a less competitive firm might be better off using independent channel intermediaries to mitigate price competition. We consider two scenarios depending on whether the two firms make their distribution channel decisions sequentially or simultaneously. Although firms are unlikely to make such decisions at exactly the same instant, the simultaneous model also serves as a proxy for the scenario where firms decide sequentially, but where they cannot observe each other's strategic channel choices. For the sequential case, we find that the sequence of entry can have tremendous impact on the two firms'profits; whereas in some cases, the first mover can achieve substantially higher profits, we find that when the two markets are of sufficiently different size and only loosely related, a firm with a competitive advantage might be better off as a follower. Interestingly, our results suggest that, when the markets are of rather similar size, both firms are better off if they enter the industry sequentially. In those cases, the first entrant has incentive to reveal its planned channel strategies, and the follower has incentive to seek out and consider this information. © 2010 Wiley Periodicals, Inc. Naval Research Logistics, 2010  相似文献   
153.
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   
154.
During their 60 years within the North Atlantic Treaty Organisation (NATO), Denmark and Norway have experienced both high and low standings within the alliance, which can be attributed to both external and internal factors influencing their alliance strategies. During the ‘first’ Cold War and Détente, 1949–79, Danish and Norwegian alliance strategy aimed to simultaneously deter and reassure the Soviet Union. During the ‘second’ Cold War, 1979–89, Danish alliance policy became driven by domestic politics, and the Danish government was forced to formally dissociate the country from NATO's policies. Norway was not uncritical, but held a much lower profile. After the Cold War this situation shifted. Denmark successfully rehabilitated itself as a loyal and dependable ally by responding to the call for focusing on out-of-area operations. Meanwhile, Norway's continued focus on the lingering Russian Threat made the country seem out-of-touch with priorities in the post-Cold War alliance, and domestic politics prevented a more active out-of-area engagement.  相似文献   
155.
The contemporary American counterinsurgency discourse has emphasised a particular historical narrative of Vietnam to justify large-scale military operations in Iraq and Afghanistan. Absent from this narrative is any reference to the broader Cold War context in which Vietnam existed alongside numerous other small-scale counterinsurgencies and was therefore the exception, not the rule. This article seeks to redress this shortcoming by examining the way counterinsurgency was conceived and managed at the level of ‘grand strategy.’ Specifically, it focuses on the Special Group (Counterinsurgency) to demonstrate that senior policymakers under Presidents Kennedy and Johnson understood ‘counterinsurgency’ as involving ‘indirect’ assistance to foreign governments, rather than taking ‘direct’ military action with American ground forces.  相似文献   
156.
In conflict studies, identity has been posited as an explanatory factor of the resilience of insurgencies. This article focuses on the identity formation of the National Liberation Army (ELN), a leftist insurgency group in Colombia. As a Marxist–Leninist organisation, the ELN aims to overcome capitalism. In their perception, this is possible via the transformation of the individual into a ‘collective personality’. Along the dimensions of ‘content’ and ‘contestation’, we will demonstrate the mechanisms they impose for such identity formation. Identity, as we will argue, is a main factor in explaining why people participate in this insurgency and thereby enhance its resilience.  相似文献   
157.
This article analyzes how the conflict environment in which a civilian monitoring mission is deployed influences the monitors' assessment of the operation. It draws on unique empirical material from the experience of the Sri Lanka Monitoring Mission (SLMM), deployed to oversee a ceasefire agreement in Sri Lanka 2002–2008. With material from a survey and in-depth interviews, experiences of the monitors are analyzed and changes over time are traced in relation to the monitors' assessment of the mandate and organizational set-up of the mission. The study points to the difficulty of monitoring missions to address escalation during an ongoing peace process. Its function is dependent on the goodwill of the parties. In essence, monitoring missions have the potential to strengthen peace when there is momentum in favor of progress, but when relations between the parties turn sour and the conflict escalates a civilian monitoring mission basically loses its potential. During the final stages of the war, which saw a very large number of civilian casualties, the war-torn areas were closed to international observers. Moreover, international pressure for a short-term ceasefire to alleviate the humanitarian situation was dismissed by the Sri Lankan government, which also saw the backing of several important actors, not the least China.  相似文献   
158.
159.
Wm. Roger Louis, Imperialism at Bay 1941–1945. The United States and the decolonization of the British Empire. Oxford: Clarendon Press, 1977. Pp. xvi + 595;£12.50.

Christopher Thorne, Allies of a Kind. The United States, Britain and the war against Japan, 1941–1945. London: Hamish Hamilton, 1978. Pp. xxii + 772; £15.00.

Michael Howard, editor, Restraints on War: Studies in the Limitation of Armed Conflict Oxford: Oxford University Press, 1979. Pp. viii + 173; £6.50.

Julian Lider, The Political and Military Laws of War: an Analysis of Marxist‐Leninist Concepts. Farnborough, Hants: Saxon House, 1979. Pp. vii + 266; £12.50.

Klaus‐Jürgen Müller and Eckardt Opitz (editors), Militär und Militarismus in der Weimarer Republik. Düsseldorf: Droste Verlag, 1978. Pp. 304; n.p.

Nicholas Bethell, The Palestine Triangle: The Struggle Between the British, the Jews and the Arabs 1935–1948. London: Steinmatsky's Agency Ltd. in association with Andre Deutsch, 1919. Pp. 384; £7.95.

Sir Maurice Dean, The Royal Air Force and Two World Wars. London: Cassell, 1979. Pp. 349; £8.95.

Wilfred Jay Holmes, Double‐Edged Secrets. Annapolis, Maryland: Naval Institute Press, 1979. Pp. 218, n.p.

S. G. Gorshkov, The Sea Power of the State. Oxford: Pergamon Press, 1979. Pp. 290; £15.00.

Kirk, Grayson and Wessell, N.H. eds., The Soviet Threat: Myths and Realities. New York and London: Praeger, 1978. Pp. 182; £12.00.

Kenneth E. Boulding, Stable Peace. Austin and London: University of Texas Press, 1978. Pp. 155;£2.80.

Kenneth E. Boulding (ed.), Peace and the War Industry. New Brunswick, NJ: Transaction Books, and Oxford: Basil Blackwell, 1973. Pp. vii + 213; £2.75.  相似文献   
160.
This article describes and analyzes a little understood Afghan Taliban propaganda tool: chants or taranas . These melodic refrains effectively use historical narratives, symbology, and iconic portraits. The chants are engendered in emotions of sorrow, pride, desperation, hope, and complaints to mobilize and convince the Afghan population of the Taliban's worldview. The chants represent culturally relevant and simple messages that are communicated in a narrative and poetic form that is familiar to and resonates with the local people. They are virtually impossible for the United States and NATO to counter because of Western sensitivities concerning religious themes that dominate the Taliban narrative space, not to mention the lack of Western linguistic capabilities, including the understanding and mastering the poetic nature of local dialects.  相似文献   
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