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321.
International concern over nuclear terrorism has grown during the past few decades. This has driven a broad spectrum of efforts to strengthen nuclear security globally, including the widespread adoption of radiation-detection technology for border monitoring. Detection systems are now deployed at strategic locations for the purported purpose of detecting and deterring the smuggling of nuclear and radioactive materials. However, despite considerable investment in this area, few studies have examined how these programs are implemented or the operational challenges they face on a day-to-day basis. This article seeks to address this with a focus on radiation-detection efforts at maritime facilities. Utilizing practitioner interviews and a survey, this article identifies the factors that influence the planning and use of these systems in this fast-moving environment. The results clearly demonstrate that the implementation of these systems varies significantly across different national and organizational contexts, resulting in a fragmented global nuclear-detection architecture, which arguably undermines efforts to detect trafficked nuclear-threat materials. Greater consideration should therefore be given to developing international standards and guidance, designing and adopting tools to support key parts of the alarm assessment process, and broader sharing of good practice.  相似文献   
322.
Cyberspace is a new domain of operation, with its own characteristics. Cyber weapons differ qualitatively from kinetic ones: They generate effects by non-kinetic means through information, technology, and networks. Their properties, opportunities, and constraints are comparable to the qualitative difference between conventional and nuclear weapons. New weapons and their target sets in a new domain raise a series of unresolved policy challenges at the domestic, bilateral, and international levels about deterrence, attribution, and response. They also introduce new risks: uncertainty about unintended consequences, expectations of efficacy, and uncertainty about both the target’s and the international community’s response. Cyber operations offer considerable benefits for states to achieve strategic objectives both covertly and overtly. However, without a strategic framework to contain and possibly deter their use, make state and non-state behavior more predictable in the absence of reciprocal norms, and limit their impact, an environment where states face persistent attacks that nonetheless fall below the threshold of armed conflict presents a policy dilemma that reinforces collective insecurity.  相似文献   
323.
The past decade has seen substantial shifts in Swedish security policy and major change in the domestic debate about NATO. For the first time, all of the right-of-centre “alliance parties” are calling for a full NATO membership, and popular support for NATO has increased. Yet public opinion contains ambiguities and paradoxes that complicate the picture. At the same time as support for NATO has increased, the public is overwhelmingly for continued military non-alignment. Drawing on previous research, longitudinal data from national surveys, and other sources on defence and security issues, this article aims to increase our understanding of the development and change in Swedish public opinion on NATO. A key argument is that Erving Goffman’s theatre metaphor, combined with neo-institutional decoupling theory, to a large degree can help understand the public opinion paradox.  相似文献   
324.
A dynamic multi-stage decision-theoretic approach is introduced to establish the optimal offset and its incidence, the contract price arising from bargaining, and the scale of the acquisition. A new rationale is suggested for offsets in terms of their role as an insurance devise. Results are derived for the pricing of delivery contracts subject to offset claims and their national security implications. It is shown that the national security is strictly convex in the offset transaction. As to the incidence of the offset, the offset claim is shown to be capitalised in the delivery price. The bargaining price is shown to depend on the value of the product to be delivered for the national security, the relative negotiation power of the contracting partners and the social cost of public funds. The analysis highlights the expectation effects of offsets on the bargaining price and the scale of delivery. The results aid in explaining why offsets are widely used in procurement contracts for defence materiel. As they contribute to the national security, they should be allowed to survive and not be denied under competition laws.  相似文献   
325.
326.
Between 2014 and 2017, no less than 10 different non-governmental organizations (NGOs) conducted maritime Search and Rescue (SAR) operations off the coast of Libya. By rescuing over 100,000 migrants in three years, these NGOs became the largest provider of SAR in the Mediterranean. The theory of institutionalism suggests that organizations conducting similar activities are likely to converge in a process of mimetic isomorphism, deliberately imitating one another to increase their effectiveness and cope with uncertainty. These 10 SAR NGOs, however, developed two different rescue models: While some rescued migrants and disembarked them in Italian ports, others only simply assisted those in distress until the arrival of another ship transporting them to land. They also cooperated with Italian and European authorities to different degrees. Why did SAR NGOs imitated many elements of existing non-governmental rescue models, but discarded some others? This article argues that differences in material capabilities and organizational role conceptions are crucial to explain why newer SAR NGOs have imitated most but not all of their predecessors’ policies, engaging in a process of “selective emulation.”  相似文献   
327.
Following Russia’s annexation of Crimea and its initial actions in eastern Ukraine in 2014, the term hybrid warfare has received much public attention. Many have argued that the Russian actions we saw in Ukraine were part of a completely new strategy while others have suggested that there was nothing new in Russia’s actions. This article takes a critical look at these claims. Through the assessment of the history of the term hybrid warfare and a rigorous analysis of the so-called Gerasimov doctrine, this study finds that the Russian hybrid warfare strategy is rather a western myth than a formal comprehensive Russian strategic concept. Additionally, through the assessment of the Russian use of information operations and the way she has utilised the cyberspace in several recent conflicts, the study finds that against all claims Russia did not make these areas its main battlefield, but rather has been using them in support of its traditional concepts.  相似文献   
328.
经典的侦察与监测(S&R)系统效能分析方法存在模型难以建立、结果不准确等问题。考虑到S&R系统的目的是提供情报支持,提出一种基于信息需求的S&R系统情报支持效能分析方法。该方法以用户的信息需求为度量基准量,比较S&R系统性能对信息需求的满足度,并以此满足度作为S&R系统效能度量的指标。仿真实例表明了新方法的有用性。  相似文献   
329.
主要就IC卡技术在我军器材保障信息管理中的初步应用,阐述了基于IC卡技术的便携式器材保障信息系统的特点和系统组成方案,并介绍了实现这种系统方案的关键技术.  相似文献   
330.
针对高动态环境下飞行器组合导航系统因不确定故障导致导航精度下降的问题,提出了一种基于矢量信息分配的容错联邦滤波算法。设计矢量形式的故障检测函数,对各观测量进行单独的故障程度划分,克服了将故障子系统所有观测量同时隔离的缺陷;根据观测量是否异常,重构时变量测噪声矩阵和信息分配矢量系数,对子滤波器的状态变量进行信息分配,在隔离故障子系统异常观测量的同时,最大限度地利用正确观测信息。仿真结果表明,采用该算法能够充分发挥各导航子系统的优势,极大提高了导航子系统信息利用率,具有较高的精确性和容错性。  相似文献   
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