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171.
奥巴马对联合国政策的调整,反映出奥巴马政府全球外交和安全战略的需要,体现了实用主义外交风格。较之于其前任,奥巴马将更加重视联合国维和行动,并让联合国更多地参与解决包括伊拉克和阿富汗在内的热点问题。奥巴马的联合国政策面临挑战,联合国仅仅是奥巴马实现美国国家利益的手段之一。  相似文献   
172.
独立学院应用型人才培养质量保障体系的构建   总被引:1,自引:0,他引:1  
独立学院承担着为区域经济和社会发展培养应用型高级专门人才的任务。为了确保人才培养的质量,应从师资队伍建设、实践教学、教学质量监控、评价体系建设、教材建设及学风建设等方面,构建完善的独立学院应用型人才培养质量保障体系。  相似文献   
173.
We study optimal pricing for tandem queueing systems with finite buffers. The service provider dynamically quotes prices to incoming price sensitive customers to maximize the long-run average revenue. We present a Markov decision process model for the optimization problem. For systems with two stations, general-sized buffers, and two or more prices, we describe the structure of the optimal dynamic pricing policy and develop tailored policy iteration algorithms to find an optimal pricing policy. For systems with two stations but no intermediate buffer, we characterize conditions under which quoting either a high or a low price to all customers is optimal and provide an easy-to-implement algorithm to solve the problem. Numerical experiments are conducted to compare the developed algorithms with the regular policy iteration algorithm. The work also discusses possible extensions of the obtained results to both three-station systems and two-station systems with price and congestion sensitive customers using numerical analysis.  相似文献   
174.
We study an (R, s, S) inventory control policy with stochastic demand, lost sales, zero lead‐time and a target service level to be satisfied. The system is modeled as a discrete time Markov chain for which we present a novel approach to derive exact closed‐form solutions for the limiting distribution of the on‐hand inventory level at the end of a review period, given the reorder level (s) and order‐up‐to level (S). We then establish a relationship between the limiting distributions for adjacent values of the reorder point that is used in an efficient recursive algorithm to determine the optimal parameter values of the (R, s, S) replenishment policy. The algorithm is easy to implement and entails less effort than solving the steady‐state equations for the corresponding Markov model. Point‐of‐use hospital inventory systems share the essential characteristics of the inventory system we model, and a case study using real data from such a system shows that with our approach, optimal policies with significant savings in inventory management effort are easily obtained for a large family of items.  相似文献   
175.
This note studies the optimal inspection policies in a supply chain in which a manufacturer purchases components from a supplier but has no direct control of component quality. The manufacturer uses an inspection policy and a damage cost sharing contract to encourage the supplier to improve the component quality. We find that all‐or‐none inspection policies are optimal for the manufacturer if the supplier's share of the damage cost is larger than a threshold; otherwise, the manufacturer should inspect a fraction of a batch. © 2008 Wiley Periodicals, Inc. Naval Research Logistics, 2008  相似文献   
176.
The US government initiated a Defense Counterproliferation Initiative to address the concern that, in the post-Cold War years, the proliferation of nuclear, biological, and chemical weapons would be widespread and create a significant challenge to the US military’s combat operations. In particular, non-nuclear states might use chemical or biological warfare agents against US forces with the belief that nuclear weapons would not be used against them in retaliation. Following the events of September 11, 2001, defense strategy and policy shifted to a wider view of the threat of adversarial use of “weapons of mass destruction” (WMD) and the term “counterproliferation” was replaced by “combating” or “countering WMD.” Over time, the Defense Department increasingly moved away from counterproliferation principles with the detrimental effect of losing capabilities that US forces still need for contemporary adversaries. This shift has been aggravated by other US government agencies’ use of “counterproliferation” in lieu of what would have been termed “nonproliferation” activities in the 1990s. The loss of clarity within the US government on these terms has led to the inability to focus the “whole of government” on this significant national security challenge. To alleviate this challenge, the US government needs a top-down initiative to refocus policy on the distinctly different aspects of WMD with respect to military combat operations, combating terrorism, and homeland security.  相似文献   
177.
The decision to employ force abroad is often a contentious political decision, where partisanship plays a crucial role. Prior to military intervention, political parties usually make their ideologically distinctive preferences clear and seek to implement them once in power. What remains unclear, however, is how ideology affects the decision to use military force. This article contends that alliance and electoral calculations constrain the ability of political parties to implement their ideological preferences with regards to the use of force. It examines a “most likely” case for the partisan theory of military intervention, namely Canada’s refusal to take part in the invasion of Iraq and its decision to commit forces to the war against the Islamic State. It finds that only in combination with alliance and electoral calculations does executive ideology offer valuable insights into Canada’s military support to U.S.-led coalition operations, which contributes to our understanding of allied decision-making.  相似文献   
178.
Canada is now at a crossroads unlike any other period in its history and needs to carefully consider which path to take. With the new Trudeau government comfortably ensconced since the defeat of the Harper government in the fall of 2015, a variety of competing interests have emerged in an attempt to turn Canadian policy back to a more nostalgic period of the 1970s that some see as preferable to the institutional lash-up that existed since the rolling out of the Canada First policy in the 2000s. That nostalgic period is, however, misunderstood both willfully for political purposes but also through a lack of historical context. Firmly rooting future actions in a blunt analysis of national interests is preferable to the alternative.  相似文献   
179.
动态频谱接入面临的关键技术之一是对接入时机和方式进行有效地管控,防止由于频谱的接入使用过于灵活造成用频的干扰和混乱。将频谱接入的时间和方式给予规则上的约束和指导,基于规则构建动态频谱管理框架可以有效实现频谱的实时管控。对动态频谱接入的规则及表述方式进行了讨论,分析了基于规则的动态频谱接入过程,最后结合美军XG项目的试验结果分析了基于规则的动态频谱接入的应用前景。  相似文献   
180.
将装备保障人员按级别分为操作人员、维修人员及管理人员,结合人员进入、培训和退出的状态,构造了状态转移矩阵,求出了各级别人员数量。定义了不同级别针对不同任务的保障效率,按照保障人员完成最高效率任务构建了最优化配置模型。通过实例验证了模型的实用性。  相似文献   
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