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991.
This article considers the problem of monitoring Poisson count data when sample sizes are time varying without assuming a priori knowledge of sample sizes. Traditional control charts, whose control limits are often determined before the control charts are activated, are constructed based on perfect knowledge of sample sizes. In practice, however, future sample sizes are often unknown. Making an inappropriate assumption of the distribution function could lead to unexpected performance of the control charts, for example, excessive false alarms in the early runs of the control charts, which would in turn hurt an operator's confidence in valid alarms. To overcome this problem, we propose the use of probability control limits, which are determined based on the realization of sample sizes online. The conditional probability that the charting statistic exceeds the control limit at present given that there has not been a single alarm before can be guaranteed to meet a specified false alarm rate. Simulation studies show that our proposed control chart is able to deliver satisfactory run length performance for any time‐varying sample sizes. The idea presented in this article can be applied to any effective control charts such as the exponentially weighted moving average or cumulative sum chart. © 2013 Wiley Periodicals, Inc. Naval Research Logistics 60: 625–636, 2013 相似文献
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993.
提出了一种安全私有云解决方案,是通过研究云计算安全体系模型,结合私有云架构特点设计的一种安全架构。与其他私有云解决方案相比,该架构安全系数较高,具有多层次、可扩展和强安全的特点。能够保证云用户安全快速登录云系统,使用透明加解密来保证用数据的可用性和安全性,实现了云数据的密文访问控制功能,增强了云存储数据的机密性,为私有云解决方案提供安全技术保障。 相似文献
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996.
S. Mansoob Murshed 《Defence and Peace Economics》2013,24(5):391-401
This paper constructs a macroeconomic model of North–South interaction where the flow of narcotics from the South to the North is restricted. The economic effects are akin to quantitative restrictions in trade policy. Two alternative policy scenarios will be considered. One involves reducing the supply of drugs at the source, accompanied by aid. Supply‐side restrictions have negative aggregate supply‐side effects in the producing region, because of the monopoly rents generated from that type of control. This makes them a second‐best policy, particularly if the accompanying aid is not used for poverty alleviation and fails to expand domestic aggregate demand. Alternatively, demand side restrictions will be found to be superior. 相似文献
997.
We look at the different ways of aggregating the exports of dual use products to give the security perception of exporter countries and their consistency with the relevant export control regimes. Also, we analyze different models of export controls highlighting the role of the perception of security, market structure and competition between exporting firms in determining the existence of multiple equilibria and therefore, the need for coordination between countries in setting export controls. 相似文献
998.
Cassady B. Craft 《Defence and Peace Economics》2013,24(1):127-148
During the Cold War, two contending hypotheses dominated theories concerning the economic impact of anus control. The first suggested that when certain prerequisites were fulfilled, arms control agreements served to promote lasting reduction in military spending. The second asserted that instead of promoting savings, arms control encouraged diversion of resources to more advanced and expensive weapons, thus driving defense spending higher. Through the examination of the impact of the Washington Naval Agreements on naval expenditure during the 1920s, this paper provides empirical evidence to support the latter of these competing hypotheses. The United States, Great Britain, and Japan all realized economic savings after signing the Washington Naval Agreements. However, these savings soon eroded as the powers developed more advanced weapons‐systems. 相似文献
999.
Togzhan Kassenova 《The Nonproliferation Review》2013,20(2):379-401
Because it is a producer and supplier of high-tech dual-use goods as well as a major transit point for WMD-related and military items, Taiwan represents an important case study of national export control systems. Taiwan is not an official member of the major multilateral export control regimes, yet it remains committed to nonproliferation goals. The article explores the strategic trade controls of Taiwan within the context of its nonproliferation policies and commitments. The author discusses the strong and weak aspects of Taiwan's strategic trade controls by looking in detail at key components of the country's export-import control system: legal basis, licensing system, enforcement and compliance mechanism, government-industry outreach, and adherence to nonproliferation treaties and multilateral export control regimes. 相似文献
1000.
军用移动电站的并网系统在向电网馈电的过程中,当电网电压波动,特别是系统工作于轻载时,会使并网系统输出电流畸变,电流谐波含量增高.在研究传统并网电流控制的基础上,首先提出将重复控制引入电网电压前馈控制计算中,达到抑制电网突变对系统前馈的影响和消除电网周期性扰动产生的电流畸变的目的,提高了系统稳定性;然后采用前馈控制和PI控制器串联方式,保证系统的动态性能.实验结果表明,基于重复控制的前馈补偿方法便于实现,该方法能够降低并网电流总谐波,提高系统稳态特性和并网输出电压质量. 相似文献