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631.
Arian L. Pregenzer 《The Nonproliferation Review》2013,20(3):529-538
International technical cooperation on issues relevant to the challenges of nuclear disarmament can demonstrate commitment to obligations under Article VI of the Treaty on the Non-Proliferation of Nuclear Weapons, strengthen the security of fissile materials and weapons, and develop technical approaches to support more ambitious disarmament activities in the future. Including non-nuclear weapon states would ensure that their views are taken into account and would invest them in developing solutions to key challenges. This article discusses three areas for technical cooperation that would build on past activities and that could produce such benefits as improved protection, control, and accounting of nuclear weapons and fissile material; enhanced transparency for nuclear weapon complexes; and mechanisms for international management of sensitive civilian nuclear facilities. International cooperation in each of these areas could provide a technical basis for pursuing possible future disarmament negotiations and substantively demonstrate commitment to Article VI. 相似文献
632.
在系统奇点唯一的条件下,研究了一类微分系统不存在极限环的的充分条件,运用和发展了以往的结果. 相似文献
633.
针对竞争失效产品加速寿命试验存在试验时间长、费用高、效率低的问题,提出了一种基于Monte-Carlo仿真的竞争失效产品步降加速寿命试验优化设计方法.采用Monte-Carlo对步降加速寿命试验进行仿真模拟,以正常使用应力下的p阶分位寿命渐进方差估计最小为目标,以各试验应力水平及对应应力下的试验截尾数作为设计变量,采用MIE理论进行统计分析,建立了基于仿真的竞争失效产品步降加速寿命试验优化设计模型.最后,通过实例分析表明:该方法具有可行性、有效性. 相似文献
634.
时变环境下基于加速寿命试验的产品故障预测方法 总被引:1,自引:0,他引:1
针对传统可靠性模型及分析方法无法分析产品在时变环境下可靠性的缺陷,提出了时变环境应力下产品可靠性预测方法.引入比例风险模型描述产品可靠性与工作环境因素的关系,结合加速寿命试验数据,利用极大似然估计确定基准失效率函数及各环境因素协变量回归系数.在假设产品工作环境应力转换时间确定的情况下,建立了时变环境下可靠度分析模型.实例验证了该方法的有效性. 相似文献
635.
A. S. Andreou ? K. E. Parsopoulos ? M. N. Vrahatis § G. A. Zombanakis 《Defence and Peace Economics》2013,24(5):481-495
The issue that this paper tackles is the assessment of the relative security benefits that Cyprus and Greece derive in the context of their cooperation on defence matters. This form of cooperation, known as the ‘Integrated Defence Space Doctrine’, aims at defending their interests in the Aegean Sea and the broader East Mediterranean theatre. The paper relies heavily on earlier research on this topic, which deals with the Greek–Cypriot alliance facing an arms race against Turkey, and uses a coefficient especially designed to assess the optimal levels of security and the associated defence expenditure of the two allies. A comparison of the relative security coefficient values for the two allies suggests that the security benefit that Greece derives thanks to its alliance with Cyprus exceeds the corresponding Cypriot benefit by far. Given the importance assigned to human resources by this index, in conjunction with the demographic problems of Greece, this conclusion justifies the recent Greek defence policy revision, emphasizing quality, capital equipment and flexibility of forces. This revision aims at satisfying the security requirements of the alliance and the increasing demands of an arms race against Turkey. 相似文献
636.
The economic theory of defense has traditionally described public safety as achieved through investments that deter adversaries. Deterrence is, however, ineffective and pre‐emptive defense is required when a population of intended victims confronts supreme‐value suicide terror. A moral dilemma then arises, since pre‐emption may impose collective punishment, while in the absence of pre‐emption the population of intended victims is exposed to acts of terror. We consider how a population of intended terror victims confronts the moral dilemma, and compare the threatened population's response with the public‐safety recommendations of external judges who are not personally affected by the threat of terror. 相似文献
637.
An examination of past analyses suggests that today's sailors may be less responsive to compensation changes than previous generations. Such a change could make recruiting and retaining high‐quality sailors more difficult. However, variation in researchers' decisions over time may simply have created the appearance of such a change. Our results suggest there is little variation in the pay elasticity over time. In contrast, the different reduced‐form models we use to measure this relationship can explain most of the variation in the literature. Therefore, the evidence suggests that while sailors may have changed over time, their response to compensation has not. 相似文献
638.
ANDREA E OSTHEIMER 《African Security Review》2013,22(4):45-58
Guinea-Bissau's transition toward democracy has been violent and disruptive. Despite holding elections and attempts to promote economic and social development, the latest government, under President Yala, is not equipped to bring stability or even a more democratic state. A politicised military, inexperienced opposition and corrupt government officials have contributed to the current poverty and instability. Although unlikely to be deposed by the fragmented opposition, Yala is not secure within his own party and is likely to use his position to weaken his opponents. As a Catholic, Yala has been careful to avoid religious conflict by reassuring Muslim citizens that they will not be marginalised. The economy is precarious and poverty has not been addressed. Guinea-Bissau is dependent on foreign donors for its financial needs. Guinea-Bissau has begun military operations against rebels opposing the Senegalese government and the battles seem likely to continue to cause regional instability. Without external intervention political and economic development looks remote. 相似文献
639.
L EN LE ROUX 《African Security Review》2013,22(1):105-107
640.
AbstractThis paper offers a simple strategic framework to help governments identify various policy mechanisms to minimize public sector corruption. The paper offers a formal model that blends the economics of crime with identity economics and money laundering. It presents a partial equilibrium framework that focuses on a representative public official engaged in a mix of legal and illegal effort. The model introduces various levers a government might use to impact the costs and benefits of illegal effort. The ultimate goal is to help turn volatile vicious cycles of political instability, into steady virtuous cycles of stability, growth, and sustainable development. 相似文献