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371.
States confronting cross-border intrusions of terrorism, illegal immigration, and/or drug trafficking weigh the costs of such intrusions against the costs of imposing barriers to prevent or curb the intrusions. In such situations, the degree of national security afforded a state depends, in large measure, upon the degree of border openness the state chooses. Depending upon the intensity and frequency of the intrusions – expressed in terms of opportunity-cost functions – a state might have little choice but to pursue a border policy of zero openness. It is this relationship of border openness to national security that explains why many states choose to construct security fences. In the 49 cases of security fences examined, many – among them Israel vis-à-vis the West Bank, India vis-à-vis Pakistan, Turkey vis-à-vis Greece in Cyprus – the construction of security fences becomes more complicated by their placement on lands whose sovereignties are disputed.  相似文献   
372.
In the years since the 2003 Rose Revolution, the popularly elected leadership of the Republic of Georgia has responded to organized protests with a variety of repressive tactics. These reactions suggest that former challengers to authoritarian elites may utilize similar methods of retaining power during crisis periods. Yet, the alleged involvement of agencies of the Russian Federation in fomenting domestic instability has also occupied a central position in the national security policies of the outgoing Saakashvili government. These conditions both preceded and were reinforced by the South Ossetia War of August 2008. This article proposes a theoretical model that represents the intervening effect of interstate conflicts on state–society relations in Georgia from 2003 to present. It presents several hypotheses and possible indicators, data sources, and techniques for analyzing the interaction between characteristics of opposition groups, external threats, and the domestic security practices of contemporary Georgian political elites.  相似文献   
373.
Following the 11 September 2001 attacks, the US government increased its counterterrorism (CT) funding and created several Federal Agencies such as the Department of Homeland Security; Transportation Security Administration; and National Counterterrorism Center. Similarly, the 7 July 2005, London bombings also compelled the British government to increase its CT funding. These examples illustrate a phenomenon that when states experience terrorism, they dramatically increase public safety spending in order to reduce or eliminate the incidents of and casualties resulting from acts of terror. Using statistical data collected from 34 countries covering nine years, this article examines recent CT spending increases. Critically, the authors explore whether recent public safety expenditures can measurably reduce the number of domestic and international terrorist attacks. The implications of their findings should be salient for policy-makers’ assessments of their countries’ current CT strategies and policies concerning their respective Intelligence and Security Communities.  相似文献   
374.
This article explores Russia's increasing reliance on nuclear weapons from three perspectives. First, it seeks to demonstrate that the phenomenon is not exclusively limited to Russia and represents a broader trend, which is ultimately rooted in the nature of the contemporary international system or, more precisely, the uncertainties of the transitional period between the Cold War system and a new emerging one. Second, it analyzes the role assigned to nuclear weapons in Russia's doctrinal documents, in particular the emergence of a new mission—limited-use of nuclear weapons to deter or, if deterrence fails, to de-escalate large-scale conventional conflicts. Discussions of the new doctrine, which have begun recently, suggest that this new mission will likely remain unchanged. Finally, this article looks at the apparent discrepancy between Russia's nuclear modernization programs and the roles assigned to nuclear weapons in the military doctrine, as well as the causes of that discrepancy.  相似文献   
375.
基于IPSec的下一代高性能安全处理器的体系结构   总被引:1,自引:0,他引:1       下载免费PDF全文
IPSec是目前适合所有Internet通信的惟一一种安全技术。通过分析IPSec的处理过程,指出网络安全处理器的使用是IPSec协议高效实现的关键,并详细介绍了目前典型安全处理器的结构和应用。由于目前的网络安全处理器无法满足OC 48及其以上速率接口的处理要求,对下一代高速网络安全处理器的体系结构进行了分析和预测。  相似文献   
376.
The study shows how ‘strategic military refusal’ in Israel developed as a rational and institutional means to influence security policies. As opposed to the perspective that sees military refusal as a spontaneous individual act, the study illustrates how organizations operate to distribute military refusal in order to pressure decision-makers to change their military policies. This strategy has proven to be effective when the military is involved with groups that threaten it with refusal – which threatens the military's operational ability and its official and apolitical image. These include soldiers whose civilian authorities, rather than their military commanders, are perceived as an epistemic authority regarding security issues. The case study refers to the impact of strategic military refusal in Israel on security policies and the military doctrine. This was influenced by leftist groups, which, although they belonged to the parliamentary opposition, had dominant presence in the military ranks. Furthermore, the study examines the effect of the use of strategic military refusal on the model of military recruitment.  相似文献   
377.
At NATO’s 2014 Wales Summit, the UK and Germany unveiled two new initiatives for European defence cooperation, known, respectively, as the Joint Expeditionary Force (JEF) and the Framework Nations Concept (FNC). Both were the result of economic pressures and the need to exercise intra-alliance leadership, but they represented very different approaches to cooperation. The JEF was to be a UK-led contingency force for short-notice operations, selectively incorporating forces from allies and partners. The FNC sought to coordinate capability development between groups of allies, centred on larger framework nations, to develop coherent capability-clusters available to meet NATO’s force requirements. The common denominator and novelty of the initiatives was the building of forces and capabilities multinationally by having major states act as framework nations for groups of smaller allies. The UK and Germany have ownership and continue to provide leadership to these initiatives. This is one key reason why they continue to evolve to accommodate changing circumstances and are likely to endure.  相似文献   
378.
It is widely acknowledged that maritime security in the Gulf of Guinea is a highly complex phenomenon involving a variety of issues (legal deficiencies, inadequate military equipment, and challenges like corruption, political unrest and youth unemployment) as well as a multiplicity of external responders. To make sense of the impact that external actors have when they address this complex problem through various maritime capacity building endeavours, this article argues that there is a need to understand the attractiveness of capacity building vis-à-vis the widely acknowledged need for a comprehensive approach, as well as the difficulties of translating the potential for comprehensiveness into practice (as important aspects of the problem remain largely unaddressed). Further, it is argued that it is important to appreciate that even if these gaps – i.e. the aspects that maritime capacity building currently leaves unaddressed – represent a ‘failure’ to deliver a comprehensive response, they are at the same time illustrative of how the maritime capacity building activities of various external actors also ‘succeed’ in having an impact on this regional security landscape – for instance, by influencing how certain aspects of this multifaceted problem are prioritised, whilst others are only marginally addressed, if at all.  相似文献   
379.
为在复杂旁路攻击敌手环境下对密码芯片进行安全评估,通过物理可观测密码术模型框架对旁路分析过程进行建模;借鉴传统面向实际的可证明安全性理论,定义旁路环境下的两类旁路敌手:密钥恢复旁路分析敌手与不可分辨性判定旁路分析敌手,并给出了密码实现针对这两类旁路敌手的安全性度量模型;对安全性评估中的重要参数指标进行定义与推导;最后根据旁路分析定义、模型及安全性度量指标,提出针对旁路分析的通用评估框架,为研究可抵抗旁路分析攻击的密码设备打下基础。  相似文献   
380.
传统通信系统安全风险评估方法获取的判断矩阵是个体专家的意见,无法处理不确定问题,得到的评估结果较为主观、准确度差,为了解决该问题,提出了基于证据理论的通信系统安全风险评价模型。采用证据理论融合规则调整通信设备和光缆一级指标的判断矩阵,综合多位专家的意见,获取设备和光缆各指标的状态评分和指标权重,构建通信系统风险评估模型,最后通过仿真实验测试其性能,结果表明,该模型可以准确评估通信系统的风险等级。  相似文献   
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