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761.
王涛 《武警工程学院学报》2013,(6):36-38
为了有效解决基于内容图像检索中“语义鸿沟”问题,利用贝叶斯决策理论估计图像检索中相关图像集与不相关图像集合的分类面,通过移动查询点的策略,指导新一轮的查询,将查询点移向好的范例点而远离坏的范例点。试验证明该方法是一种有效的基于统计分析的反馈方法。 相似文献
762.
为支持军事通信业务的智能化,研究了军事通信业务上下文信息的表示和推理,提出了一种表示业务上下文信息的语法结构、语义以及上下文元信息的本体建模方法。并利用贝叶斯网络理论,提出了一种支持不确定性推理的业务上下文认知模型的构建方法,最后通过案例分析验证了模型和结论的合理性。 相似文献
763.
Hans Mouritzen 《Defense & Security Analysis》2013,29(4):342-355
Security Intergovernmental Organizations, here illustrated by NATO, persist in a “permitted interval” of internationalization, i.e. permitted by its member-states. On the one hand, they are seldom or never permitted to vanish due to member-states' vested interests in retaining them as tools of statecraft, even if their original purposes have become redundant. On the other hand, there is an internationalization ceiling that they must respect: they should not become too autonomous and thereby no longer be suitable as member-state tools. In spite of post-Cold War reform, interviews carried out at NATO Headquarters (HQ) in the late 1980s compared to interviews in 2012 display that a continuous pulling and hauling of forces of internationalization and renationalization have taken place around NATO HQ. The only instance of clear internationalization can be observed in the proactive diplomacy of Secretary General Fogh Rasmussen. There is stiff opposition to the internationalization of abolishing the Military Committee/International Military Staff among minor and South European states, and there is no waning in states' attempts to micro-manage the International Staff. Only external shocks can overcome resistance to internationalizing reform. 相似文献
764.
In this article, we consider a problem in which two suppliers can sell their respective products both individually and together as a bundle, and study the impact of bundle pricing. Four pricing models (centralized, decentralized, coop–comp, and comp–coop) are analyzed with regard to the competition formats and sequences. As one would expect, the firms are always better off when pricing decisions are centralized. However, rather surprisingly, we find that firms may be worse off if the bundle prices are set in a cooperative way; we provide analytical characterization of those instances. Numerical studies show that these insights also hold for some nonlinear demand. © 2013 Wiley Periodicals, Inc. Naval Research Logistics, 2013 相似文献
765.
This article presents a flexible days‐on and days‐off scheduling problem and develops an exact branch and price (B&P) algorithm to find solutions. The main objective is to minimize the size of the total workforce required to cover time‐varying demand over a planning horizon that may extend up to 12 weeks. A new aspect of the problem is the general restriction that the number of consecutive days on and the number of consecutive days off must each fall within a predefined range. Moreover, the total assignment of working days in the planning horizon cannot exceed some maximum value. In the B&P framework, the master problem is stated as a set covering‐type problem whose columns are generated iteratively by solving one of three different subproblems. The first is an implicit model, the second is a resource constrained shortest path problem, and the third is a dynamic program. Computational experiments using both real‐word and randomly generated data show that workforce reductions up to 66% are possible with highly flexible days‐on and days‐off patterns. When evaluating the performance of the three subproblems, it was found that each yielded equivalent solutions but the dynamic program proved to be significantly more efficient. © 2013 Wiley Periodicals, Inc. Naval Research Logistics 60: 678–701, 2013 相似文献
766.
This article assesses the existing literature on logistics in war, concluding that there is no satisfactory conceptual definition of logistics. It proposes a concept of logistics derived from Clausewitz's theory of war to fill that void. This is presented as a derivation because Clausewitz's distinction between (1) the use of the fighting forces (tactics and strategy) and (2) all other activities in war that were required so that forces could be taken as a given. The latter, left unnamed by Clausewitz, corresponds to a concept of logistics that proves to be an analytical peer to Clausewitz's categories of politics, tactics and strategy. 相似文献
767.
侯衍勇 《武警工程学院学报》2014,(4):27-30
根据抢险救援任务中装备保障的基本要求,结合抢险救援装备保障的现状,针对完成任务过程中所暴露的问题,从保障预案、保障行动、资源整合和工作组织四个方面,阐述了抢险救援装备保障应采取的措施,为提高部队装备保障水平、提升部队抢险救援能力,提供了可借鉴的理论探索。 相似文献
768.
王岚 《武警工程学院学报》2014,(4):90-92
网络信息技术的发展,给图书馆带来了巨大变革。图书馆为顺应时代发展积极采取各种措施,实现了组织方式、工作方式和服务方式等多方面的改革与创新。但是,如何从“信息用户”和“信息服务”方面进行组织、开发、交流和提供的状态,使用户以多种方式获取信息、处理信息,还面临许多问题。从图书馆用户需求的变化和图书馆服务模式变革等方面看,通过不断推出新的工作方式和服务形式,可以催生出新兴图书馆业态,促进图书馆多元化趋势的快速发展。 相似文献
769.
Oriana Skylar Mastro 《战略研究杂志》2019,42(1):114-152
What factors do autocracies evaluate when responding to perceived threats and why might they fail to balance appropriately? I posit that autocratic leaders may choose greater exposure to an external threat if, by doing so, it preserves regime legitimacy. Specifically, the desire to promote a positive image to one’s domestic public creates incentives to publicly downplay a rival’s military progress, which then affects the state’s ability to mobilize resources to respond to the growing threat. I test this theory in the case of China’s response to India’s military rise. This research contributes to balancing theory and empirical work on East Asian security. 相似文献
770.
朱岩 《海军工程大学学报》1997,(4)
运用图式理论解释了阅读理解的心理过程,叙述了文化背景知识对阅读理解的作用和影响,对一项文化背景知识测试结果进行了分析和讨论.研究结果表明:学习和运用文化背景知识的能力是阅读能力中不可缺少的重要组成部分;了解文化背景知识的渠道是多种多样的;学生的文化背景知识水平有待于进一步提高. 相似文献