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851.
This article puts forth collection action as a unifying theme for the conference essays on arms trade, control, and production. For each of these topics, collective action failures are related to group size and group composition considerations. Other issues are also examined including the manner in which individual contributions determine the overall level of the associated collective good ‐ the so‐called aggregation technology of public supply. Based on alternative aggregation technologies, the game‐theoretic underpinnings of these arms issues are explored.  相似文献   
852.
If international terrorism is on a rising trend, an important source of confirmation or refutation of this is time‐series data on terrorist activity. Using chiefly data collected by the RAND/MIPT consortium we show using basic statistical analysis that in the period 1968–2005 the yearly number of all international terrorist incidents shows no trend over time, but fluctuates year on year in a random manner. On the other hand some indicators do show a definite trend over time, principally the steady rise in the number of incidents that are death‐dealing in nature. A further conclusion is drawn, showing that the proportion of these incidents leading to deaths above a given level is virtually fixed.  相似文献   
853.
Kovenock and Roberson's (2012a, b) replication of Hausken’s (2008a) equations and parameter restrictions do not enhance our insight into the defense and attack of reliability systems. This reply intends to fill the remaining understanding gaps.  相似文献   
854.
This paper uses game theory and modeling to address the role of incentive structures and information dynamics in nuclear inspections. The traditional argument is that compliant states should be willing to allow inspections to prove their innocence, while proliferating states are likely to impede inspections. This argument does not take into account the historical variation in inspection, signaling, and sanctioning behaviors. Using a game theoretic analysis and model, it is shown that the separation of proliferators from nonproliferators only occurs when the likelihood of proliferation is high and punishment costs are moderate. The model assumes that states can choose how much to cooperate with inspectors and must pay opportunity or secrecy costs when inspections are effective. The results are tested against a set of real-life cases, providing support for the claims of historical variation and the model's deductive propositions.  相似文献   
855.
基于复杂网络理论,分析了信息化作战系统网络结构,构建了传统作战系统和信息化作战系统拓扑模型的生成算法,并通过对传统作战系统和信息化作战系统结构拓扑模型度量性质的比较,说明了信息化战争下的作战系统结构特点,为进一步研究网络化战争提供了良好的模型基础.  相似文献   
856.
ABSTRACT

This article explores the paradox of trust in the largest nuclear smuggling operation involving highly enriched uranium (HEU) discussed in open source literature. In the first effort to understand the type, extent, and role of trust in nuclear smuggling enterprises, it draws from literature on trust development in legitimate businesses as well as criminal enterprises. Observed behavioral patterns in this case challenge traditional notions of the internal dynamics of temporary groups engaged in nuclear smuggling and operational realities of such activities. The article seeks to explain why individuals agree (and continue) to operate in this high-risk environment, unbound by close personal ties, without any effort to verify the background, motives, or qualifications of the fellow conspirators. It offers ways to advance current nonproliferation efforts in non-state actor interdiction by exploiting the environment of shallow trust in temporary groups.  相似文献   
857.
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   
858.
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   
859.
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   
860.
基于改进LMS算法的复合材料超声检测缺陷识别   总被引:1,自引:0,他引:1  
在径向基函数(RBF)神经网络实现无人机复合材料超声检测脱粘缺陷识别时,针对最小均方(LMS)算法在确定网络输出权值时存在稳态失调误差和收敛速度相矛盾的问题,提出一种改进的自适应的变步长LMS算法.该算法根据反馈误差自适应确定步长,通过引进动量项加快收敛速度.将改进LMS算法应用到RBF网络缺陷识别中,结果表明该方法在稳态失调误差较小的情况下,能快速确定RBF网络的权值.改进的RBF网络能够较好地识别超声检测脱粘缺陷.  相似文献   
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