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471.
重点阐述了排列熵算法的基本原理,总结归纳了该算法在医学、生物和机械等领域的国内外研究和应用现状,最后展望了排列熵算法的未来发展趋势。研究表明:排列熵算法能够有效放大时间序列的微弱变化,且计算简单、实时性高,已在信号突变检测方面显示出良好的应用前景。 相似文献
472.
为研究埋入式抗滑桩在滑坡治理中的适用性,总结前人经验并经大量现场调查研究,提出埋入式抗滑桩支护的3种失效模式,即桩后滑体整体失稳、桩顶滑体越顶失稳和桩前滑体滑移失稳;并从失效模式入手,简化埋入式抗滑桩支护边坡稳定性分析模型。结合定点剪出的破坏假定,用传递系数法分别验算桩周3部分土体即桩后土体、桩顶土体和桩前土体的稳定性。最后在埋入式抗滑桩支护边坡稳定性分析模型的基础上,围绕滑体几何形态、滑面倾角、滑带及滑体力学性质等关键因素,对埋入式抗滑桩的适用条件进行探讨。研究表明:埋入式抗滑桩置于平缓段有利于其阻隔作用的发挥,保证桩前滑体的稳定性;置于滑体强度大于滑带强度的滑坡,有利于利用滑体较高的土工参数;置于坡面平缓的滑坡,有利于桩顶滑体的稳定。 相似文献
473.
Lazar Berman 《战略研究杂志》2013,36(1):121-147
The question of what enables some militaries to innovate effectively is of great interest to both scholars and commanders. However, the traditional models of military innovation fail to capture the complex innovation process. This study develops a new analytical framework that examines the pressures on and incentives for military innovation in the international, civil/military, organizational, and cultural planes and uses it to evaluate Israel Defense Forces (IDF) innovation between 2000 and 2009. Based on interviews with Israeli commanders and extensive research in Israel, this work finds that the IDF struggled to innovate before the 2006 war against Hizballah, but innovated effectively after the conflict once military and civilian leaders understood threats similarly. New models are needed to analyze the contemporary multi-dimensional innovative process. 相似文献
474.
475.
We introduce a generalized orienteering problem (OP) where, as usual, a vehicle is routed from a prescribed start node, through a directed network, to a prescribed destination node, collecting rewards at each node visited, to maximize the total reward along the path. In our generalization, transit on arcs in the network and reward collection at nodes both consume a variable amount of the same limited resource. We exploit this resource trade‐off through a specialized branch‐and‐bound algorithm that relies on partial path relaxation problems that often yield tight bounds and lead to substantial pruning in the enumeration tree. We present the smuggler search problem (SSP) as an important real‐world application of our generalized OP. Numerical results show that our algorithm applied to the SSP outperforms standard mixed‐integer nonlinear programming solvers for moderate to large problem instances. We demonstrate model enhancements that allow practitioners to represent realistic search planning scenarios by accounting for multiple heterogeneous searchers and complex smuggler motion. © 2013 Wiley Periodicals, Inc. Naval Research Logistics, 2013 相似文献
476.
吴恺 《兵团教育学院学报》2013,(3):24-28
高校协同创新是指高校与科研机构、企业、政府之间,围绕国家重大科技项目和各行业关键技术,投入各自优势资源,合作攻关,力求取得重大突破的创新性活动。高校协同创新具备动态性、多元性、融合性、持续性的特点。要改进和完善我国高校协同创新,需要创建良好的协同创新组织方式、培养协同创新的思想观念、形成良好的创新型人才培养机制。 相似文献
477.
Theory on the use of information technology in military operations assumes that bringing together units in an information network helps units to work together. Decentralized command systems such as mission command have been proposed for these networks, so that units can adapt to changes in their turbulent working environments. Others have proposed centralized command systems that permit higher organizational levels to closely direct military operations. This article uses Perrow’s (1984, 1999) Normal Accidents Theory to propose that increasing interdependencies between units in information networks places incompatible demands on the design of networked military operations. It is concluded that networked military operations require decentralized command approaches, but only under the condition that interdependencies between modules of networked units are weak rather than tight. This precondition is essential for retaining control over networked military operations. 相似文献
478.
Nina A. Kollars 《战略研究杂志》2015,38(4):529-553
Wartime adaptation is a process of adjustment from the war you planned for to the one you have. This process of adjustment is done, in part, by the practitioners of war in the theater of conflict–soldier-led adaptation. Drawing upon two case studies of gun truck development in Iraq and Vietnam I argue that soldiers created networks in order to adapt to battlefield challenges and that the pattern of those networks carries implications for the likelihood of formal adoption by the organization. Simply put, the pattern of the flow of ideas, resources, and skills across the battlefield may affect the likelihood of bottom-up adaptation. 相似文献
479.
Estimating demand functions for developing countries before and after the end of the Cold War, Dunne and Perlo-Freeman (2003) found little evidence of any change in the underlying relationship. One concern with their analysis was that the use of cross-section averages might have obscured important time series effects. This paper deals with this issue by analysing their data using static and dynamic panel data methods. This produces evidence of a change in relationship and suggests that the focus in the literature on cross-section analyses has indeed limited our understanding of important dynamic processes at work within countries. 相似文献
480.
DEREK BRADDON 《Defence and Peace Economics》2013,24(6):499-507
In this paper, we employ a VAR analysis to examine the nexus between military spending and economic growth in Sri Lanka which, due to the civil war there, has witnessed a significant increase in military spending over the last three decades while also recording healthy economic growth. The study finds that, compared with non‐military spending, military spending exerts only a minimal positive impact on real GDP. Over a 10‐year period, a 1% increase in non‐military spending increases GDP by 1.6%. In contrast, military spending only increases GDP by 0.05%, suggesting that the economic benefits for Sri Lanka from a sustained peace may be considerable. 相似文献