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141.
We consider the optimal wagers to be made by a gambler who starts with a given initial wealth. The gambler faces a sequence of two-outcome games, i.e., “win” vs. “lose,” and wishes to maximize the expected value of his terminal utility. It has been shown by Kelly, Bellman, and others that if the terminal utility is of the form log x, where x is the terminal wealth, then the optimal policy is myopic, i.e., the optimal wager is always to bet a constant fraction of the wealth provided that the probability of winning exceeds the probability of losing. In this paper we provide a critique of the simple logarithmic assumption for the utility of terminal wealth and solve the problem with a more general utility function. We show that in the general case, the optimal policy is not myopic, and we provide analytic expressions for optimal wager decisions in terms of the problem parameters. We also provide conditions under which the optimal policy reduces to the simple myopic case. © 1997 John Wiley & Sons, Inc. Naval Research Logistics 44: 639–654, 1997  相似文献   
142.
众所周知,Vo IP技术在未来语音通信中所占的比重越来越大。随着Vo IP的不断发展,基于SIP协议的Vo IP应用也不断增多。但是,由于SIP协议高度依赖于开放的IP网络,使得其安全性逐渐成为关注和探讨的焦点。主要分析了SIP协议网络面临的一些安全威胁,包括典型的外部攻击技术和协议自身存在的漏洞等。探讨了为应对SIP安全威胁提出的加密、认证等安全策略并且分析了这些安全策略的优缺点,提出了针对SIP安全策略进一步改进的方向,旨在不断提高和完善基于SIP协议的安全性能。  相似文献   
143.
近年来,各种食源性公共卫生危机引发了社会公众对转基因食品安全性的关注。转基因食品的生产方与消费方对转基因食品的安全性各执一词,尚未有足够的科学证据证明转基因食品的安全性或危险性。转基因食品的标识政策应运而生,一方面允许转基因食品的商品化,另一方面要求转基因食品明确标识,以保障消费者的知情权与选择权。研究当前主要标识管理政策,分析我国的转基因食品标识政策具有重要的现实意义。  相似文献   
144.
PANG Zhihui 《国防科技》2018,39(1):047-052
韩国自20世纪90年代起开始考虑反导系统的构建以来,其反导政策经历了"明确反对加入美国反导体系,自主构建韩国型导弹防御系统"到"强化韩美、韩美日反导合作,谋求实质上融入美国反导体系"的显著调整与变化。韩国反导政策的演变与朝鲜核、导威胁的与日俱增、韩国自身反导能力的不足及美国的极力推动等因素密不可分。当前,韩国开始部署"萨德"末段高空区域反导系统,韩美反导合作日益深入,并向韩美日三边合作拓展,且取得了实质性的进展。韩国强化与美、日的反导联合,在军事、外交、安全方面引发了广泛影响。  相似文献   
145.
中国人民武装警察部队现、退役人员及随军家属创业、就业的各项税收制度和减免税政策,是国家拥军制度的组成部分和重要体现。落实好这些政策,对于凝聚人心、鼓舞士气、保持意志,更好地完成使命具有重要意义。  相似文献   
146.
本文对“形势与政策”课的基本任务、基本特点进行了分析,并就如何加强“形势与政策”课程建设问题进行了探讨。  相似文献   
147.
This article reassesses the foreign policy legacy of George W. Bush in light of the emerging historical record of his administration. We conclude that, whereas Bush’s foreign policy was in widespread disrepute when he left office in 2009, that reputation is likely to improve – perhaps significantly – in the coming years. We identify six particular arguments that lend credence to an emerging ‘Bush revisionism.’ To be clear, we do not necessarily argue that the balance sheet on Bush’s foreign policy was positive, but the arguments presented here are likely to generate a more sympathetic and favorable historical assessment of Bush’s presidency over time.  相似文献   
148.
We consider a two‐level system in which a warehouse manages the inventories of multiple retailers. Each retailer employs an order‐up‐to level inventory policy over T periods and faces an external demand which is dynamic and known. A retailer's inventory should be raised to its maximum limit when replenished. The problem is to jointly decide on replenishment times and quantities of warehouse and retailers so as to minimize the total costs in the system. Unlike the case in the single level lot‐sizing problem, we cannot assume that the initial inventory will be zero without loss of generality. We propose a strong mixed integer program formulation for the problem with zero and nonzero initial inventories at the warehouse. The strong formulation for the zero initial inventory case has only T binary variables and represents the convex hull of the feasible region of the problem when there is only one retailer. Computational results with a state‐of‐the art solver reveal that our formulations are very effective in solving large‐size instances to optimality. © 2010 Wiley Periodicals, Inc. Naval Research Logistics, 2010  相似文献   
149.
Traditional inventory systems treat all demands of a given item equally. This approach is optimal if the penalty costs of all customers are the same, but it is not optimal if the penalty costs are different for different customer classes. Then, demands of customers with high penalty costs must be filled before demands of customers with low penalty costs. A commonly used inventory policy for dealing with demands with different penalty costs is the critical level inventory policy. Under this policy demands with low penalty costs are filled as long as inventory is above a certain critical level. If the inventory reaches the critical level, only demands with high penalty costs are filled and demands with low penalty costs are backordered. In this article, we consider a critical level policy for a periodic review inventory system with two demand classes. Because traditional approaches cannot be used to find the optimal parameters of the policy, we use a multidimensional Markov chain to model the inventory system. We use a sample path approach to prove several properties of this inventory system. Although the cost function is not convex, we can build on these properties to develop an optimization approach that finds the optimal solution. We also present some numerical results. © 2008 Wiley Periodicals, Inc. Naval Research Logistics, 2008  相似文献   
150.
科技军民融合政策制度   总被引:2,自引:0,他引:2       下载免费PDF全文
陈华雄  黄灿宏  赵理  王健  魏鹏 《国防科技》2018,39(5):062-069
科技军民融合政策制度是推动军民科技协同创新向纵深发展的基本保障和环境条件。分析了我国科技军民融合政策与管理制度的内涵、分类和组成,调研了我国科技领域军民融合有关政策现状及最新试点情况,分析了当前我国科技军民融合政策制度的缺陷点、薄弱环节,研究了国外科技有关的军民融合政策体系构建的规律及启示,提出了我国科技军民融合政策制度建设的基本思路、组织框架、建设重点和推进措施,以为我国科技军民融合政策的制定提供理论保障和决策依据。  相似文献   
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