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101.
本文利用(c,h,a)三参数旋转体模型计算了形变核的相对表面能、相对库仑能及相对转动能。这些相对能量与具体核无关,具有普适性,可以用于核裂变动态过程的模拟计算。利用这些结果,计算了一些核的形变位能随三参数变化的情况,给出了裂变位垒高度,与实验结果符合较好。对~(236)U的形变位能曲面作了较详细的分析,得出一些有益的结论。用Werner—Wheeler方法计算了形变核的惯性质量和粘滞张量随三参数变化情况,对断点线方程作了深入讨论,为核裂变动态过程的计算机模拟准备了必要的系数。  相似文献   
102.
ABSTRACT

Recent historical research exposed the myth of self-restraint as the distinctive feature of British counterinsurgency during decolonisation. This article shows that the revisionist historiography of British counterinsurgency has important, but unnoticed, implications for political scientists. Specifically, historical scholarship challenges the predictions and causal mechanisms of the main social scientific theses of civilian victimisation in counterinsurgency. Using revisionist historians’ works as a source of data, I test those theses against Britain’s decolonisation conflicts. I find that they do not pass the test convincingly. I conclude that political scientists should be more willing to explore the theoretical implications of new historical evidence on counterinsurgency campaigns.  相似文献   
103.
ABSTRACT

The present international standard allows non-nuclear weapon states (NNWS) to forego safeguards when nuclear material is used in a “non-proscribed military activity,” though no criteria have been established to determine when NNWS can remove naval nuclear material from safeguards. Though at present, only nuclear-armed states possess nuclear submarines, the global nuclear naval landscape may soon change with the advancement of Brazil's fledgling program and the possible precedent it would set for other NNWS. A framework is needed to shore up nuclear security and prevent nuclear material diversion from the nuclear naval sector. Proposed and existing nonproliferation frameworks, including a Fissile Material Cut-off Treaty and commitments through the nuclear security summits, are insufficient to close this loophole. A Naval Use Safeguards Agreement (NUSA), modeled after the Additional Protocol of the International Atomic Energy Agency, would provide a framework to remove the opacity surrounding nuclear material in the naval sector. Designed for NNWS and encouraged as confidence-building measures for nuclear weapon states, NUSA would explicitly outline those stages in the naval nuclear fuel cycle where safeguards are to be applied and in what context. This viewpoint also further provides direction for targeted research and development in technical naval nuclear safeguards solutions.  相似文献   
104.
This article seeks to elucidate the concept of nuclear learning. It explores both the “nuclear” and the “learning” aspects of the concept. On the nuclear side, it distinguishes between learning basic facts about nuclear arms and drawing inferences about the larger implications of those facts. On the learning side, it discusses three issues: whether to use the term in a normative or value-neutral manner; the difference between learning that leads to a change in means versus learning that leads to a re-evaluation of ends; and whether learning only takes place at the level of individuals or whether there can also be learning by collective entities. The article argues there is no universal best answer to these questions and that the particular concept of learning that should be employed depends on the goals of the analyst. If the goal is to reduce the chances of nuclear war, however, one type of learning that will be important to consider is whether there is shared, cross-national learning.  相似文献   
105.
Unprecedented interest in seeking progress toward nuclear disarmament exists today; even some nuclear weapon states are looking for new ways to strengthen this process. National declarations of fissile material holdings—highly enriched uranium and plutonium—could play an important role in supporting this effort, facilitating not only transparency but also the irreversibility of the process. This article discusses what kind of content such declarations could have in order to be meaningful and effective, the sequence of data on fissile material holdings that states might release, and some of the challenges to be expected in reconstructing historic fissile material production; it also summarizes current attitudes of weapon states toward making such declarations. Initial declarations can be valuable as confidence-building measures, but better and more background data are necessary if declarations are to serve as the groundwork for deeper cuts in the nuclear arsenals. A robust verification approach would ultimately require inspectors to have access to fissile material production and storage sites. The methods and tools of nuclear forensic analysis—in this context also dubbed nuclear archaeology—would be a key element of this process. This article discusses the capabilities and limitations of potential approaches to verifying declarations of historic production of plutonium and highly enriched uranium; it also identifies and discusses opportunities for further research and development.  相似文献   
106.
Bomboozled: How the U.S. Government Misled Itself and Its People into Believing They Could Survive a Nuclear Attack, by Susan Roy. Pointed Leaf Press, 2011. 176 pages, $45.  相似文献   
107.
ABSTRACT

This article explores how two influential American policy makers—Paul Nitze and McGeorge Bundy—wrestled with the idea of a norm against the use of nuclear weapons. Existing scholarship has overlooked how both Bundy and Nitze came to understand the idea of nuclear non-use, especially related to the credibility of threats to use nuclear weapons. Using documentary evidence from their personal papers, this article illuminates the thinking of Bundy and Nitze, finding that both engaged with the idea of a norm of non-use of nuclear weapons in their strategic writing and thought.  相似文献   
108.
ABSTRACT

There have been calls for the abolition of nuclear weapons from the day they were invented. Over the last fifteen years, some indications can be found that such calls have been getting louder, among them Barack Obama's famous 2009 speech in Prague. In this article, we investigate if support for a comprehensive norm that would prohibit development, possession, and use of nuclear weapons is really growing. To assess the current status of that norm, we use the model of a “norm life cycle,” developed by Martha Finnemore and Kathryn Sikkink. We then analyze 6,545 diplomatic statements from the review process of the Treaty on the Non-Proliferation of Nuclear Weapons as well as from the UN General Assembly First Committee on Disarmament and International Security, covering the years 2000 to 2013. The evidence shows that a comprehensive prohibition can be considered an emerging international norm that finds growing support among states without nuclear weapons and nuclear weapon states alike. Only a core group of states invoke the norm consistently, however. This leads us to conclude that the “tipping point” of the life cycle, at which adherence to a new norm starts to spread rapidly, has yet to be reached.  相似文献   
109.
Latin American countries have historically followed different paths and logics toward the nonproliferation regime. Some states have unconditionally advocated for global and nonproliferation efforts, while others have vehemently opposed such measures or remained ambivalent toward the regime itself. By historically comparing two of Latin America's most influential countries—Brazil and Mexico—this study identifies the underlying domestic conditions and external influences that explain their differences in behavior and policy toward the nonproliferation regime. Because little is known about the reasons why different Latin American countries adopt these different approaches, the purpose of this article is to resolve this problem, primarily by focusing on the ways in which evolving civil-military relations and US influence have shaped nonproliferation policy preferences in Latin America. It concludes with a discussion of how these historical cases might shed light on current nonproliferation policies in Latin America.  相似文献   
110.
This viewpoint takes stock of the changes in the strategic nuclear landscape in recent decades and reflects on its consequences on the policy community. It finds that the number and scope of issues have expanded considerably; they have manifested themselves in many more regions of the world; and they have become deeply politicized and polarized. The consequences have been twofold: the nuclear policy field has seen the development of an increasingly diverse expert community composed of highly specialized functionalists and regionalists, and it has become ever more divided into two entirely separate ideological camps—one that believes in deterrence, the other in disarmament. The stove-piping of expertise and the widening gap between deterrence and disarmament ideologies are immensely problematic because, in different ways, they stand in the way of the emergence of a better and safer nuclear future. Looking ahead, it is critical to “bust the silos of expertise” and to build bridges between the deterrence and disarmament ideological camps. Only such a community-building effort will help solve today’s and tomorrow’s nuclear challenges.  相似文献   
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