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91.
基于警报关联的网络威胁行为检测技术因其与网络上大量部署的安全产品耦合,且能充分挖掘异常事件之间的关联关系以提供场景还原证据,正成为复杂威胁行为检测的研究热点。从威胁行为和网络安全环境的特点出发,引出威胁行为检测的应用需求和分类,介绍基于警报关联的威胁行为检测的基本概念和系统模型;重点论述作为模型核心的警报关联方法,并分类介绍了各类典型算法的基本原理和特点,包括基于因果逻辑的方法、基于场景的方法、基于相似性的方法和基于数据挖掘的方法;并结合实例介绍了威胁行为检测系统的三种典型结构,即集中式结构、层次式结构和分布式结构;基于当前研究现状,提出了对未来研究趋势的一些认识。  相似文献   
92.
The terrorist attacks in France and Belgium of 2015–2016 that occurred while these countries were in a heightened state of alert raise questions about indications and warning methodology as well as effectiveness of the blanket-protection deployment of security services assisted even by the military. Response and perhaps even more anticipation may require strategic rethinking in light of the predatory attacks that target the most vulnerable spots of the public space. This study looks at threat analysis in Belgium as conducted through her intelligence fusion centre Coordination Unit for Threat Analysis (CUTA)?????? since its inception in 2006. With a special focus on what is known, at the time of writing, about the terrorist attacks in Paris and Brussels, this study hopes to put into context how the system (mal)functions and will also consider the preventive measures that respond to the threat, and the international aspects which have implications far beyond Belgian borders. Therefore, a case is made for not just a Belgian homeland security framework, but one that fits into an EU-wide security concept.  相似文献   
93.
《防务技术》2022,18(11):2097-2106
The target's threat prediction is an essential procedure for the situation analysis in an aerial defense system. However, the traditional threat prediction methods mostly ignore the effect of commander's emotion. They only predict a target's present threat from the target's features itself, which leads to their poor ability in a complex situation. To aerial targets, this paper proposes a method for its potential threat prediction considering commander emotion (PTP-CE) that uses the Bi-directional LSTM (BiLSTM) network and the backpropagation neural network (BP) optimized by the sparrow search algorithm (SSA). Furthermore, we use the BiLSTM to predict the target's future state from real-time series data, and then adopt the SSA-BP to combine the target's state with the commander's emotion to establish a threat prediction model. Therefore, the target's potential threat level can be obtained by this threat prediction model from the predicted future state and the recognized emotion. The experimental results show that the PTP-CE is efficient for aerial target's state prediction and threat prediction, regardless of commander's emotional effect.  相似文献   
94.
目标威胁评估是空战决策研究的重要组成部分,评价指标是进行威胁评估的前提和基础。根据现代空战的特点,借鉴网络中心战思想,从空间态势、物理域、信息域、认知域4个角度,构建了信息化条件下空战目标威胁评估指标体系,并对指标体系进行了完备性、合理性、有效性检验。通过实例分析表明威胁评估指标能较好地反映信息化条件下空中目标的实际威胁,为空战决策研究提供参考。  相似文献   
95.
针对火箭弹卷弧尾翼在特定气动载荷下的轻量化问题,基于结构动力学理论,依托ABAQUS非线性有限元软件,建立了火箭弹卷弧尾翼的有限元模型。通过对比碳纤维复合材料(CFRP)和合金钢材料的卷弧尾翼的有限元分析,得出了碳纤维复合材料在满足强度和刚度的要求下,使卷弧尾翼减重达80%。该方法为火箭弹卷弧尾翼的轻量化设计提供了一种参考和借鉴。  相似文献   
96.
97.
In the ten years since the establishment of South Africa's first inclusive democratic government, an ambitious, extensive and systematic process of reform has been carried out in the governance of security. The process is widely regarded as having been successful and a model for other processes of ‘security sector reform’ in the context of transitions from authoritarian forms of governance to democratic ones.

That this been achieved with hardly a shot fired in anger is a remarkable achievement and a credit to visionary political leadership as well as organisational capacity, in other words to effective security governance.

At the same time, progress has been uneven and sometimes fragmentary, policy intentions and commitments have not always been translated into practice, the end results have not been to everyone's liking, and transformation has engendered its own pathologies. Thus several challenges remain in improving security governance.

This article provides a broad overview of the roles played by the various actors in the governance of the security sector, including the executive, parliament and civil society. It examines the main policy frameworks and touches on organisational transformation, because it is impossible to deal with governance in isolation from these issues. Policy processes and the frameworks they give rise to—in particular—are critical for effective governance. This article deals with the defence, safety and security and intelligence fields. A comprehensive overview would need to include the governance of criminal justice and foreign policy. The article does not seek to make an overall evaluation of governance, but to identify achievements, shortfalls and challenges.  相似文献   
98.
Abstract

The mandate of South Africa's recently appointed National Planning Commission includes addressing ‘defence and security matters’. This article seeks to outline the central elements of the threat environment facing South Africa in the foreseeable future. It is argued that South Africa faces no meaningful existential threat from conventional military forces but that its security forces will need to be prepared to address possible raids and attacks by conventional military forces both on home soil and on vital interests beyond the nation's borders. Other threats highlighted include the threats posed by potential insurgencies, by terrorism, and by crime, social unrest and banditry. Also addressed is the danger of so-called hybrid threats, in which two or more of the single threat types outlined here are combined. Finally, the article challenges the National Planning Commission to rethink South Africa's policy on peace operations in the light of the need to ensure the safety and security of the nation's citizenry.  相似文献   
99.
目前,不协调决策表的分布约简、最大分布约简和分配约简算法复杂度较高,不适合处理大数据集。在分析已有算法基础上,分析了基于相对可区分度的属性重要性度量的性质,解决了正域度量属性重要性的缺陷。针对不协调决策表,给出了多种简化协调决策表的定义,从而大大缩减了约简的实例数。以相对可区分度为启发函数构造了一种高效完备的不协调决策表约简算法。理论分析和实验结果表明,该约简算法解决了现有算法在复杂度和属性重要性度量上的缺陷,适合处理不协调的大数据集。  相似文献   
100.
简述了各种武器效能评定方法。建立武器参数效能模型,首先要挑选特征参数,这里采用知识约简方法选择武器的特征参数。利用神经网络理论建立了参数效能模型,武器系统的效能与武器特征参数的关系可通过神经网络的阈值和权值得到体现。通过实例对神经网络法与指数法所得的结果进行了比较,结果表明神经网络法比指数法精确。  相似文献   
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