首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   350篇
  免费   5篇
  2021年   3篇
  2019年   8篇
  2018年   3篇
  2017年   10篇
  2016年   4篇
  2015年   5篇
  2014年   7篇
  2013年   105篇
  2010年   4篇
  2008年   3篇
  2007年   4篇
  2006年   2篇
  2005年   4篇
  2004年   2篇
  2003年   3篇
  2002年   3篇
  2001年   2篇
  2000年   4篇
  1999年   4篇
  1998年   3篇
  1996年   6篇
  1995年   7篇
  1994年   6篇
  1993年   5篇
  1992年   6篇
  1991年   4篇
  1990年   3篇
  1989年   6篇
  1988年   8篇
  1987年   7篇
  1986年   9篇
  1985年   7篇
  1983年   3篇
  1982年   9篇
  1980年   5篇
  1979年   3篇
  1978年   4篇
  1977年   5篇
  1976年   3篇
  1975年   5篇
  1974年   5篇
  1973年   6篇
  1972年   5篇
  1971年   9篇
  1970年   4篇
  1969年   6篇
  1968年   5篇
  1967年   5篇
  1966年   2篇
  1948年   3篇
排序方式: 共有355条查询结果,搜索用时 15 毫秒
251.
There are a great number of queueing systems, including the MX/MY/c, the GlX/M/c and the discrete Gl/G/1 queue in which the state probabilities are determined by repeated queue equations. This paper gives a simple, efficient and numerically stable algorithm to caiculate the state probabilities and measure of performance for such systems. The method avoids both complex arithmetric and matrix manipulations.  相似文献   
252.
This paper analyses the E/M/c queueing system and shows how to calculate the expected number in the system, both at a random epoch and immediately preceding an arrival. These expectations are expressed in terms of certain initial probabilities which are determined by linear equations. The advantages and disadvantages of this method are also discussed.  相似文献   
253.
An example of a network with flow costs depending on congestion is presented for which no system of tolls and subsidies exists which can ensure that all equilibria in the game of route selection are Pareto optimal.  相似文献   
254.
255.
An attacker, being one of two types, initiates an attack at some time in the interval [-T, 0]. The a priori probabilities of each type are known. As time elapses the defender encounters false targets which occur according to a known Poisson process and which can be properly classified with known probability. The detection and classification probabilities for each type attacker are given. If the defender responds with a weapon at the time of attack, he survives with a probability which depends on the number of weapons in his possession and on attacker type. If he does not respond, his survival probability is smaller. These probabilities are known, as well as the current number of weapons in the defender's possession. They decrease as the number of weapons decreases. The payoff is the defender's survival probability. An iterative system of first-order differential equations is derived whose unique solution V1(t),V2(t),…,Vk(t) is shown to be the value of the game at time t, when the defender has 1, 2,…, k,… weapons, respectively. The optimal strategies are determined. Limiting results are obtained as t→-∞, while the ratio of the number of weapons to the expected number of false targets remaining is held constant.  相似文献   
256.
In recent years many large government and commercial organizations have developed large-scale management information systems. During the early phases of any system development, questions are likely to be raised concerning the criteria of completeness and accuracy of the data. How to respond to these questions is difficult, and represents the general subject of this paper. In particular, this paper describes the application of statistical techniques, namely, various kinds of multivariate data analysis, to the problem of assessing the quality of a large-scale data collection system in the U. S. Navy. Results of using these techniques are described and indicate their usefulness as auditing procedures. While the discussion is placed in a particular context, the procedures should be of value for other large-scale information systems.  相似文献   
257.
258.
Comments that Donald Trump made while campaigning to be U.S. president have raised concerns that his administration will pull back from U.S. alliance commitments and encourage countries such as Japan and South Korea to acquire nuclear arms. The new article by Frühling and O’Neil outlines an institutional framework that can be helpful in assessing the risks that Trump administration policies will lead to nuclear proliferation. An institutional perspective shows that important elements of U.S. security assurances will continue to function, and this reduces the chances that President Trump’s actions or statements will trigger proliferation by U.S. allies. The greatest risk to global non-proliferation efforts posed by a Trump administration in fact lies elsewhere, in the possibility that President Trump will seek to abrogate the Iran nuclear deal.  相似文献   
259.
NATO burden sharing has become an especially timely issue in the past several years as a result of a number of factors, including Russian annexation of Crimea and destabilization of eastern Ukraine in 2014. This article argues that alliance unity among the great democracies of Europe and North America is indispensable to peace and stability on the Eurasian continent. A fractured NATO, and especially, a large divide in purposes or commitments as between the United States and its European security partners, invites aggression and the possibility of inadvertent escalation. Past successes and failures in US-involved multinational peace and stability operations, within and outside of Europe, show that mission accomplishment requires give and take, including the occasional acceptance of unequal costs and benefits among the members, in order to achieve peace and security objectives.  相似文献   
260.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号