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排序方式: 共有551条查询结果,搜索用时 15 毫秒
81.
避雷针保护范围的图形仿真与图解法分析 总被引:1,自引:0,他引:1
针对避雷针设计过程中计算公式过于复杂的问题,提出了利用平面几何作图求解避雷针联合保护范围的方法,给出了单支、双支和四支避雷针保护范围的作图解题步骤,并利用计算机图形仿真,给出了避雷针保护范围的空间结构图形。 相似文献
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83.
设计安全策略模型时应考虑安全策略的时序特性和灰色特性,还应综合考虑保密性、完整性和可用性三方面的需求。已有的安全模型没有描述时序性和灰色特性,而且一般只侧重描述保密性或完整性。为此,本文提出了动态灰色时序系统(简称DGTS)。本文详细描述了DGTS,以及基于DGTS的动态语义设计的灰色时序安全策略规范语言GTSL。 相似文献
84.
Jacques Fontanel 《Defence and Peace Economics》2013,24(2):135-147
The evolutions of military expenditures in Eastern and Central European countries are difficult to estimate and to compare, due to the lack of available data for these states. Some results of the extent of cuts in defence spending since 1990 are interesting to interpret, but it is difficult for econometricians to use these figures even carefully. The structures of national military expenditure have been modified to the detriment of arms equipment. Thus, the disarmament process needs a special analysis of the arms industry. 相似文献
85.
Charles Streeper 《The Nonproliferation Review》2013,20(3):531-550
Radioactive sealed sources have a long history and a much wider worldwide distribution than do weapons-usable fissile materials. This article compares the mechanisms for controlling radioactive sources with those of weapons-usable materials and makes the case for improved policy making on the safe and secure management of radioactive sources (often referred to simply as “sources”). Such sources have been widely distributed with commercial and government support to nearly every country, yet there are no legally binding, international agreements or regulations to control any aspect of their life cycle. This is problematic because some sources that are disused, abandoned, or otherwise fall out of regulatory control could be used in the form of a radiological dispersal device (RDD, or dirty bomb). An RDD could pose significant economic and psychological impacts with the potential for detrimental effects on public health. The lack of international measures to control sources is troubling for several reasons: creating an RDD is much easier than fashioning a nuclear weapon from scratch or from stolen fissile materials; given the many incidents involving diversion from regulatory control and the misuse of sources, an RDD attack would be one of the more likely scenarios; materials security for sources is generally weak and inconsistent; it is nearly impossible to determine the total amount of sources manufactured and distributed; used sources are frequently found uncontrolled and transiting borders, and penalties are light at best; the market-based supply and demand of sources facilitates their rapid and loosely regulated distribution; and the “peaceful uses” aspect of the Treaty on the Non-Proliferation of Nuclear Weapons along with norms that began developing around the time of Atoms for Peace have promoted the nearly unchecked global distribution of sources. Several immediate and long-term actions are suggested to reduce the threat posed by radiological sources. 相似文献
86.
Elling N. Tjønneland 《African Security Review》2013,22(3):190-196
SADC has a poor record in advancing peace and security in Southern Africa. Many identify poor policy frameworks and weak technical capacities as the major obstacles. Laurie Nathan goes beyond these easy explanations in his important new book on SADC. Absence of common democratic values and reluctance to surrender state sovereignty are key factors preventing SADC from making progress according to this book. This article argues that Nathan overstates the case and that there are real prospects and potentials for making further progress in regional cooperation. The lessons from the history of European integration also points to the important role of regional leadership. South Africa, in coalition with other likeminded countries, may still be in a position to move the SADC project forward. 相似文献
87.
Şebnem Udum 《The Nonproliferation Review》2013,20(2):365-377
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
88.
Tlohang W. Letsie 《African Security Review》2013,22(3-4):291-307
ABSTRACTThe Kingdom of Lesotho spends around five per cent of its annual budget – some 700 million Maloti ($US52.6 million) in 2017 – on the Lesotho Defence Force (LDF). Lesotho’s geographical position means that the LDF has no meaningful role regarding its primary function of defending the country from external aggression and it hardly engages in its secondary functions. In addition, the LDF has a long history of interference with democratic processes and engaging in human rights abuse. The financial resources currently allocated to the LDF could do far more for security, widely defined, if they were allocated to a number of other government expenditure categories. 相似文献
89.
Chris M.A. Kwaja 《African Security Review》2013,22(2):153-161
This paper examines the rationale and centrality of private military and security companies (PMSCs) in humanitarian assistance operations in Sudan, asking why PMSCs are involved in humanitarian assistance operations in Sudan and what the principles underlying their activities are. To answer this question, the paper draws attention to the link between humanitarian crises and PMSC interventions. Where there is no meaningful alternative intervention, undergirded by humanitarian concerns that are also profit driven, PMSCs come in to provide the needed services. The protracted and complicated internal armed conflicts in Sudan, which have lasted for over two decades, have produced as many as 4,8 million internally displaced persons (IDPs) – the single largest number in the world. The kind of humanitarian assistance operations provided by PMSCs in Sudan have become critical to the provision of much-needed services which were inadequately provided by governmental authorities at both unilateral and multilateral levels. This paper argues that the humanitarian crises in Sudan created a regime that permits humanitarian assistance operations by both state and non-state actors. 相似文献
90.
Doraval Govender 《African Security Review》2013,22(3):291-306
This article is about the management of security incidents in organisations and companies which are under the protection of private security personnel, whether in-house or contracted. Incidents can be defined as accidental or anecdotal (bird flies into a camera) to a violation of law or company policy. Managing security incidents is one of the key functions of a private security service provider. The purpose of this study is to explore the management of security incidents and the information related thereto, identify shortcomings and find solutions for managing these shortcomings. Interviews were used to gain insight from personnel within the private and government sectors which are served by the private security industry. It was found that security incidents are handled in a routine way by organisations from the different sectors. One major shortcoming is that security incidents and the information related thereto are not managed by security service providers according to an operational framework or model with the required infrastructure and resources. The significance of this study is for security incidents to be managed correctly, so that the information related thereto may be captured accurately, analysed and used proactively and reactively to improve physical protection systems, develop preventative strategies and provide actionable information products in order to reduce crime, increase detection rates and prevent losses. 相似文献