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211.
考虑到装备工况变化通常会影响到装备寿命,提出了一种基于工况-时间分布规律的装备可靠性评估及预防性维修间隔期的确定方法。采用Gamma过程描述装备性能指标退化过程,以形状参数反映工况的变化,推导出基于工况-时间分布规律的装备寿命分布;进而得到可靠度表达式,确定了预防性维修间隔期;最后给出了方法在某6300型柴油机中的应用实例,验证了方法的有效性。  相似文献   
212.
从关于国防和军队重大改革的重要论述入手,系统地阐述了武警部队重大改革必须向“能打胜仗”的战斗力聚焦。主要从三个层面进行分析:一是向提高部队整体素质及优化规模结构聚焦;二是向提高部队武器装备保障效能聚焦;三是向增强部队以执勤处突为中心的军事能力聚焦。  相似文献   
213.
We know little of the internal governing practices of non-state actors once in control of territory. Some territories have witnessed the establishment of new institutions of public goods remarkably similar to state institutions. This article compares four armed political parties governing territory during the Lebanese civil war. These non-state violent actors established complex political and economic institutions and administrative structures. Despite the wide range of ideologies and identities of these actors, they all converged in their institutional priorities, although not in their capacities or the particular ways of achieving those priorities. Data from interviews and the actions of the armed political parties suggest a combination of ideology and desire for control is causal in generating public institutions, partly attributable to the high degree of citizen activism marking the Lebanese case.  相似文献   
214.
The growth of the African Internet, and services related to the Internet, has been rapid over the last decade. Following this market expansion, a variety of service providers have started to provide access. A fast-growing market puts pressure on the providers to deliver services first and only then seek to secure the networks. Over time, industrialised nations have become more able to detect and trace cyber attacks against their networks. These tracking features are constantly developing and the precision in determining the origin of an attack is increasing. A state-sponsored cyber attacker, such as intelligence agencies and electronic warfare units, will seek to avoid detection, especially when the attacks are politically sensitive intelligence-gathering and intrusion forays into foreign states' networks. One way for the attacker to create a path that links the attacks and the originating country is by actions through a proxy. The less technologically mature developing nations offer an opportunity for cyber aggression due to their lower level of security under the quick expansion of the Internet-based market. Developing countries could be used as proxies, without their knowledge and consent, through the unauthorised usage of these countries' information systems in an attempt to attack a third country by a state-sponsored offensive cyber operation. If the purpose of the cyber attack is to destabilise a targeted society and the attack succeeds, the used proxies are likely to face consequences in their relations with foreign countries, even if the proxy was unaware of the covert activity.  相似文献   
215.
考虑到预防维修可以提高系统生产效益的同时,故障率会随着维修次数的增加而上升,引入役龄回退因子对预防维修活动前后系统性能的动态变化进行描述;而且还充分考虑到系统预防维修周期随维修次数的变化情况,建立了系统预防维修周期优化模型,并将改进后的遗传算法运用于模型的优化求解.重点研究了系统总效益随预防维修次数的变化率, 从而有效地帮助决策者判定系统何时进行更新替换.  相似文献   
216.
近年来,随着军队使命任务的拓展,涉外非战争军事行动日益成为国家运用军事力量的重要方式。因此,必须加强涉外非战争军事行动中法律保障问题研究,使其在法律框架下进行。加强对涉外非战争军事行动的法律保障,有助于为军队遂行多样化军事任务提供有力的法律支持和保障。  相似文献   
217.
‘Greed’ vs. ‘grievance’ is weighed using a generally applicable methodology as motivations in the American War of Independence. Greed is quantified as the expected economic benefit of Independence – escaping colonial trade burdens and expected increased economic growth rates. Grievance is measured as willingness to pay to escape perceived political burdens. Quantification of the relative contributions is made possible by using estimates of expected war-costs. To the extent that the economic burden was insufficient to explain the War, the residual is ascribed to the grievance motivation. Both motives are shown to have contributed to the War, but grievance dominates.  相似文献   
218.
在分析当前水面舰艇面临的现实威胁基础上,研究了指挥关系及指挥流程对水面舰艇对空防御作战效能的影响,提出利用流程仿真工具进行指挥流程的建模仿真、采用蒙特卡洛模拟方法计算作战效能的指挥关系评估方法,该理论可为指挥关系或指挥流程的优化提供技术参考和研究方向。  相似文献   
219.
The utilization of chemical weapons to quash domestic rebellion is a drastic action for a regime facing domestic challengers to take, especially given the reputation costs and risk of international intervention. However, recent developments have illustrated that some regimes have contemplated and implemented extraordinary measures (including the use of chemical munitions) to quash rebellion. This study addresses the question of why some states utilize chemical weapons against domestic challengers while others refrain from this level of state repression. I argue that the utilization of chemical weapons has both domestic and international elements. Specifically, that ethnic cleavages that lead to secessionist challenges and factors associated with inter-state rivalry impact the likelihood that a state utilizes the employment of chemical munitions. I test my argument and other explanations regarding repression with a casestudy approach utilizing captured Iraqi Government documents comparing Iraq’s Al-Anfal campaigns with developments during the recent Syrian Civil War.  相似文献   
220.
What if claims about the future informed us about the intentions and the capabilities of our opponents to wage war against ourselves? Would and should the existing norms that restrict the preventive use of force change in the wake of such transformation? This article highlights the potential normative consequences of this change and discriminates between several possible normative evolutions. Would and should the “knowability of the future” alter radically the traditional rule of self-defense? This rule could indeed be jeopardized but, as I argue in this paper, it should not (and might not necessarily). However, the distinction between preemption and prevention could become obsolete. Future claims about security will also induce new security doctrines as knowledge about the future would be used to signal one’s intentions and deter one’s opponent. This change would also have a significant impact on accountability, as citizens would have a more active role in discussions over foreign policy. Moreover, new modes of predictions and forecasting will challenge the traditional role of experts whose biases have hampered their analyses and anticipations. Thus, trustworthy future claims could bring significant progress in both ethical and political terms as they would trigger a debate on the role of knowledge in democratic societies.  相似文献   
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