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911.
研究一类具有时滞和Gompertz增长率的捕食系统,通过分析系统的特征方程,得到正平衡点的局部稳定性和系统出现Hopf分支的条件,并利用中心流形定理和规范型理论,得到确定Hopf分支方向和分支周期解稳定性的计算公式.  相似文献   
912.
The 2010 Review Conference of the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) produced a Final Document calling for an extension of the principles of the nonproliferation norm as well as steps toward complete disarmament. This article looks beyond the rhetoric, however, to examine recent decisions by great powers to expand nuclear trade with non-NPT countries and the implications of these decisions on the traditional nonproliferation norm of restraint. This article seeks to contribute to constructivist theory by supplementing existing accounts of norm creation and establishment with a new model of norm change. The article develops a case study of the 2008 US-India nuclear deal to highlight the role of elite agency in key stages of norm change, including redefinition and constructive substitution through contestation. It concludes that the traditional nonproliferation norm may be evolving in new directions that are not well captured by existing theoretical frames.  相似文献   
913.
ABSTRACT

What do we mean by nuclear proliferation? What does it mean to proliferate? This article investigates both the literal and figurative meaning of the term “proliferation.” It argues that many of the definitions and conceptualizations of nuclear proliferation often used by scholars are either limited in their utility or logically inconsistent. It then reconceptualizes and redefines the term, incorporating an understanding of both its etymological origins and the geopolitical context in which the phenomenon occurs. It concludes by exploring the potential impact that the politicization of the phenomenon may have on the identification of occurrences of proliferation, from both an academic and a policy-making perspective.  相似文献   
914.
摘要:利用泛函微分方程的度理论,研究一类具有时滞的Cohen-Grossberg神经网络的全局分支的存在性,研究结果为该类神经网络的应用设计提供理论基础.  相似文献   
915.
针对云重心和云模型评判方法存在的信息丢失、难于评判以及信息扭曲等问题,从确定权重等级、评价集和评价结果3个方面对模型进行了改进和完善.应用二元语义确定指标权重,避免了评价信息的丢失和扭曲,采用综合云的思想确定评价集,充分利用评价者给出的信息,简化相似云的理论来定量衡量评价结果,从而建立了基于云理论一二元语义的雷达装备保障指挥效能评估模型.  相似文献   
916.
一体化联合作战参战军兵种多、指挥控制(C2)与协调复杂。围绕炮兵行动特点要求,运用系统动力学理论建立联合作战炮兵行动指挥控制的系统动力学模型,研究常规打击和基于效果作战两种指挥控制模式下炮兵行动所产生的不同结果及其原因,并给合作战想定仿真验证,得出较为可靠的结论,为解决联合作战炮兵行动精确指挥控制与协调提供一种有效途径  相似文献   
917.
In this article, we explore when firms have an incentive to hide (or reveal) their capacity information. We consider two firms that aim to maximize profits over time and face limited capacity. One or both of the firms have private information on their own capacity levels, and they update their beliefs about their rival's capacity based on their observation of the other firm's output. We focus on credible revelation mechanisms—a firm may signal its capacity through overproduction, compared to its myopic production levels. We characterize conditions when high‐capacity firms may have the incentive and capability to signal their capacity levels by overproduction. We show that prior beliefs about capacity play a crucial, and surprisingly complex, role on whether the firm would prefer to reveal its capacity or not. A surprising result is that, despite the fact that it may be best for the high‐capacity firm to overproduce to reveal its capacity when capacity information is private, it may end up with more profits than if all capacity information were public knowledge in the first place. © 2013 Wiley Periodicals, Inc. Naval Research Logistics, 2013  相似文献   
918.
It has long been held that the Federation of Malaya’s counter-insurgency campaign during the First Malayan Emergency (1948–60) was determined by the use of intelligence. Special Branch — the Federation’s primary intelligence agency — dominates the prevailing paradigm of how the insurgent threat was tackled. Conversely, the role of the Royal Air Force (RAF) within this paradigm is very limited. Most observers simply dismiss the role of photoreconnaissance or airstrikes as being largely inconsequential to the counter-insurgency effort. This is perhaps understandable: the Emergency was after all a ‘policing action’ and the insurgents were largely hidden under Malaya’s jungle canopy and amongst the Chinese community. However, further scrutiny reveals that the RAF made a much more significant contribution to the intelligence element of the counter-insurgency campaign than previously realised. First, the RAF decided to locate their Advanced Headquarters with the Army’s General Headquarters. This led to the creation of the Land/Air Operations Room, through which intelligence, tasking and resources were coordinated. Moreover, the RAF put its intelligence teams into the field to provide a practical link between local units and theatre-level assets. Second, with the support of the Army, the RAF established at the beginning of the Emergency the Joint Air Photographic Intelligence Board (Far East). This coordinated all photographic intelligence requirements throughout the Emergency, which was then delivered via the Joint Air Photographic Centre (Far East). Hence, via Joint Operations Centre and JAPIB (FE), the RAF provided both the practical means for effective joint intelligence operations at theatre level throughout the Emergency.  相似文献   
919.
借鉴AHP法建立军械装备修理能力认证评估体系,并构建其递阶层次模型。确立体系各级指标权重中,引入D-S证据理论对多专家意见进行融合;综合考虑专家的权重和不确定度,并采用单值转换分布概率算法对专家评价分数进行换算,改进了AHP法受专家经验、知识限制,主观性强等缺点。经算例分析,该方法能准确可靠地评价型号装备修理机构的修理能力,减少专家主观因素对评估结果的影响。  相似文献   
920.
通过分析装备技术状态变化的模糊性和不确定性等特性,提出了基于云理论的装备技术状态预测模型.根据装备技术状态劣化趋势,给出了基于云模型的时间序列状态预测方法,有效地运用了装备状态评估中的主观预测知识.将历史趋势与当前趋势相结合,实现了基于时间序列的状态预测.最后以某装备的发动机为研究对象,对发动机状态的动态评估值进行了预测,验证了该状态预测方法的有效性.  相似文献   
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