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1.
    
This article investigates the method of allocating arriving vessels to the terminals in transshipment hubs. The terminal allocation decision faced by a shipping alliance has the influence on the scheduled arrival time of vessels and further affects the bunker consumption cost for the vessels. A model is formulated to minimize the bunker consumption cost as well as the transportation cost of inter‐terminal transshipment flows/movements. The capacity limitation of the port resources such as quay cranes (QCs) and berths is taken into account. Besides the terminal allocation, the QC assignment decision is also incorporated in the proposed model. A local branching based method and a particle swarm optimization based method are developed to solve the model in large‐scale problem instances. Numerical experiments are also conducted to validate the effectiveness of the proposed model, which can save around 14% of the cost when compared with the “First Come First Served” decision rule. Moreover, the proposed solution methods not only solve the proposed model within a reasonable computation time, but also obtain near‐optimal results with about 0.1~0.7% relative gap. © 2016 Wiley Periodicals, Inc. Naval Research Logistics 63: 529–548, 2016  相似文献   

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口岸突发事件,是指在出入境口岸限定区域突然发生的危害社会治安、损害人民生命财产安全和国家利益的事件。及时、有效地预防和处置口岸突发事件,对于维护国家的主权和领土完整,保证人民的生命财产不受侵害,保护出入境人员和交通工具的安全,维持口岸的正常出入境秩序,促进口岸的发展具有重要意义。出入境边防检查机关是否能够迅速、稳妥地处置口岸突发事件,将口岸突发事件的不良结果降到最低,有着责无旁贷和不可替代的作用。  相似文献   

4.
The funding of international nuclear risk mitigation is ad hoc, voluntary, and unpredictable, offering no transparent explanation of who is financially responsible for the task or why. Among many non-nuclear-armed states, this exacerbates a sense of injustice surrounding what they see as a discriminatory nuclear regime. The resulting erosion of the regime's legitimacy undermines support for efforts to prevent nuclear weapons dissemination and terrorism. This article proposes a transparent, equitable “nuclear-user-pays” system as a logical means of reversing this trend. This system envisions states contributing financially to international efforts to mitigate nuclear risks at a level relative to the degree of nuclear risks created by each state. “National nuclear risk factors” would be calculated by tabulating the risks associated with each state's civilian and military nuclear activities, as well as advanced dual-use and nuclear-capable missile activities, multiplying the severity of each risk by the probability of it occurring, and combining these results. A nuclear-user-pays model would create financial incentives for national and corporate nuclear risk mitigation, boost legitimacy and support for nuclear control efforts among non-nuclear-armed states, assist in preventing nuclear weapons dissemination and terrorism, and advance nuclear disarmament by helping progressively devalue nuclear weapons.  相似文献   

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随着公安边防检查站信息化建设的不断推进,基层边防检查站暴露出了大量信息安全隐患,并发生了多起信息安全事故。针对边防检查站信息安全建设中普遍存在的问题,提出了提高官兵信息安全意识、构建信息安全技术人才保障体系、健全信息安全管理机构等措施,以期为边防检查站信息安全建设提供借鉴。  相似文献   

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基于模糊证据理论的船舶安全评估   总被引:1,自引:0,他引:1  
针对船舶安全评估过程中的诸多不确定因素,提出了一种基于模糊证据理论的安全评估方法.将证据体空间中的事件视为模糊子集,并引入模糊概率,更好地描述了专家意见(或知识),给出了质量分配函数的表示.最后,结合某船舶系统,给出了其安全评估的具体实现过程.结果表明,该方法可靠、有效.  相似文献   

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介绍了信息安全风险评估的相关概念,分析了军校网络信息安全风险评估中存在的问题,并提出了应对策略,希望能对军校开展网络信息安全风险评估工作提供参考。  相似文献   

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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   

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Following work of Stroud and Saeger (Proceedings of ISI, Springer Verlag, New York, 2006) and Anand et al. (Proceedings of Computer, Communication and Control Technologies, 2003), we formulate a port of entry inspection sequencing task as a problem of finding an optimal binary decision tree for an appropriate Boolean decision function. We report on new algorithms for finding such optimal trees that are more efficient computationally than those presented by Stroud and Saeger and Anand et al. We achieve these efficiencies through a combination of specific numerical methods for finding optimal thresholds for sensor functions and two novel binary decision tree search algorithms that operate on a space of potentially acceptable binary decision trees. The improvements enable us to analyze substantially larger applications than was previously possible. © 2011 Wiley Periodicals, Inc. Naval Research Logistics, 2011  相似文献   

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This article distills insights for the scholarship of deterrence by examining the 1983 nuclear crisis – the moment of maximum danger of the late Cold War. Important contributions notwithstanding, our understanding of this episode still has caveats, and a significant pool of theoretical lessons for strategic studies remain to be learned. Utilizing newly available sources, this article suggests an alternative interpretation of Soviet and US conduct. It argues that the then US deterrence strategy almost produced Soviet nuclear overreaction by nearly turning a NATO exercise into a prelude to a preventive Soviet attack. Building on historical findings, this article offers insights about a mechanism for deterrence effectiveness evaluation, recommends establishing a structure responsible for this endeavor, and introduces a new theoretical term to the strategic studies lexicon – a ‘culminating point of deterrence’.  相似文献   

11.
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   

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Defusing Armageddon: Inside NEST, America's Secret Nuclear Bomb Squad, by Jeffrey T. Richelson. W.W. Norton & Company, 2009. 318 pages, $27.95.  相似文献   

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ABSTRACT

In No Use: Nuclear Weapons and U.S. National Security Policy, Thomas M. Nichols calls for a constructive rethinking about the history of nuclear weapons and the attitudes that have grown up around them. Despite dramatic reductions since the end of the Cold War, the United States still maintains a robust nuclear triad that far exceeds the needs of realistic deterrence in the twenty-first century. Nichols advocates a new strategy of minimum deterrence that includes deep unilateral reductions to the US nuclear arsenal, a no-first-use pledge, withdrawing US tactical nuclear weapons from Europe, and ending extended nuclear deterrence for allies. The weakest part of his argument eschews nuclear retaliation against small nuclear states that attack the United States, opting instead to use only conventional weapons to guarantee regime change. He admits this will entail enormous cost and sacrifice, but cites the “immorality” of retaliating against a smaller power with few targets worthy of nuclear weaponry, which totally ignores the massive underground facilities constructed to shield military facilities in many of these states. Despite this, Nichols's thoughtful approach to post-Cold War deterrence deserves thoughtful consideration.  相似文献   

14.
Nuclear Logics: Contrasting Paths in East Asia and the Middle East, by Etel Solingen. Princeton University Press, 2007. 404 pages, $26.95.  相似文献   

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针对容器技术在网络层面缺乏控制的问题,设计一套面向大规模容器集群的网络控制架构,分别从容器集群网络的灵活组网、智能适配以及安全隔离三个方向进行研究,主要解决大规模容器集群部署中的网络适配和隔离控制等关键问题。实验结果表明,设计的网络控制架构可以根据网络特点有针对性地实现虚拟局域网的快速划分、网络节点的稳定迁移和节点通信的精确隔离控制。  相似文献   

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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   

17.
Due to expanding and increasing religious extremism and terrorism coupled with political instability in Pakistan, most western observers believe that Pakistan's nuclear weapons are not secure and could be taken over by terrorists. This would have adverse implications for the region and for global peace, especially for the security of USA and Europe. This article argues that this perception is based on a flawed understanding and knowledge of how Pakistan's command and control setup has evolved and operates. Pakistan's nuclear weapons are as safe as any other state's nuclear weapons. Pakistan has also been active in supporting and participating in global efforts to improve nuclear safety and security. Over the years, Pakistan has been quite open in sharing information regarding how it is improving its command and control system with western governments as well as scholars. This article argues that the steps Pakistan has taken to secure its nuclear weapons are adequate and that Pakistan would continue to further strengthen these measures; however, it is the expanding religious extremism, terrorism and anti-Americanism in the country which make the international perception of Pakistan extremely negative and then seep into the perception of Pakistan's nuclear weapons safety and security.  相似文献   

18.
France still sees its nuclear arsenal as essential both as insurance against future major risks and as support for an independent foreign policy. There is a wide consensus in the country to maintain a nuclear deterrent, both among political parties and the general public. A modernization program is under way that will ensure the continued efficacy of the French nuclear force well into the 2030s, and France has adopted a fairly restrictive interpretation of its disarmament commitments under the Treaty on the Non-Proliferation of Nuclear Weapons. This suggests that the likeliest future direction of France's nuclear policy is conservatism. However, other scenarios remain possible, especially in the domain of transatlantic and/or European cooperation.  相似文献   

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The container relocation problem (CRP) is concerned with emptying a single yard‐bay which contains J containers each following a given pickup order so as to minimize the total number of relocations made during their retrieval process. The CRP can be modeled as a binary integer programming (IP) problem and is known to be NP‐hard. In this work, we focus on an extension of the CRP to the case where containers are both received and retrieved from a single yard‐bay, and call it the dynamic container relocation problem. The arrival (departure) sequences of containers to (from) the yard‐bay is assumed to be known a priori. A binary IP formulation is presented for the problem. Then, we propose three types of heuristic methods: index based heuristics, heuristics using the binary IP formulation, and a beam search heuristic. Computational experiments are performed on an extensive set of randomly generated test instances. Our results show that beam search heuristic is very efficient and performs better than the other heuristic methods.Copyright © 2014 Wiley Periodicals, Inc. Naval Research Logistics 61: 101–118, 2014  相似文献   

20.
As worries have grown about global warming and the sustainability and price of fossil fuels, the demand for nuclear energy has increased, and nuclear power is increasingly viewed as a reliable and clean resource. However, the so-called nuclear renaissance coincides with an international security environment in which the norms of nuclear nonproliferation seem to be eroding. Turkey, a non-nuclear weapon state, plans to generate nuclear power to meet future energy demands, but it is aware of and concerned with regional proliferation trends. Questions have also been raised regarding Ankara's rationale for using nuclear energy, as well as its potential motivations and capabilities regarding future proliferation. This article will provide an overview of Turkey's nuclear energy history and plans, as well as the proliferation-related questions that could arise; it will also look at the domestic debate on nuclear energy and Turkey's status as a non-nuclear weapon state.  相似文献   

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