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   344篇
  免费   17篇
  国内免费   1篇
  2021年   5篇
  2019年   9篇
  2018年   6篇
  2017年   10篇
  2016年   8篇
  2015年   6篇
  2014年   9篇
  2013年   76篇
  2012年   7篇
  2011年   5篇
  2010年   6篇
  2009年   6篇
  2008年   4篇
  2007年   4篇
  2006年   6篇
  2003年   3篇
  2002年   3篇
  2000年   3篇
  1999年   2篇
  1998年   2篇
  1997年   5篇
  1996年   7篇
  1995年   2篇
  1994年   5篇
  1993年   9篇
  1992年   6篇
  1991年   8篇
  1990年   2篇
  1989年   7篇
  1988年   5篇
  1987年   4篇
  1986年   6篇
  1985年   8篇
  1984年   5篇
  1983年   4篇
  1982年   5篇
  1981年   4篇
  1980年   8篇
  1979年   7篇
  1978年   8篇
  1976年   7篇
  1975年   10篇
  1974年   6篇
  1973年   8篇
  1972年   5篇
  1971年   4篇
  1970年   5篇
  1969年   4篇
  1968年   5篇
  1967年   3篇
排序方式: 共有362条查询结果,搜索用时 31 毫秒
301.
Ethnicity and ideology are frequently used to determine whether an armed group is hostile or friendly vis-à-vis the state. By contrast, I argue that the social structure of insurgent movements holds more explanatory power for their respective positions than ethnicity or ideology. To illustrate this, I apply Pierre Bourdieu’s concept of a contest between forces of ‘conservation’ and forces of ‘heresy’ to the current Afghanistan war. I demonstrate that the social structure of the Taleban renders them prone to ‘heresy’, while the formerly second biggest insurgent group, Gulbuddin Hekmatyar’s party, has rather been an impeded force of ‘conservation.’  相似文献   
302.
In this article we investigate the problem of locating a facility among a given set of demand points when the weights associated with each demand point change in time in a known way. It is assumed that the location of the facility can be changed one or more times during the time horizon. We need to find the time “breaks” when the location of the facility is to be changed, and the location of the facility during each time segment between breaks. We investigate the minisum Weber problem and also minimax facility location. For the former we show how to calculate the objective function for given time breaks and optimally solve the rectilinear distance problem with one time break and linear change of weights over time. Location of multiple time breaks is also discussed. For minimax location problems we devise two algorithms that solve the problem optimally for any number of time breaks and any distance metric. These algorithms are also applicable to network location problems.  相似文献   
303.
This article addresses the problem of scheduling the United States Navy's Atlantic Fleet to satisfy overseas strategic requirements. An integer programming formulation is developed but results in a model with prohibitive size. This fact and the qualitative nature of additional secondary objectives and constraints suggest an interactive optimization approach. A system that solves a natural relaxation of the integer program within an interactive environment is discussed.  相似文献   
304.
305.
It is shown that two recent results of Baxter and Harche [1] on monotone and balanced optimal assemblies hold only under conditions that are more restrictive than those originally proposed by the authors. We describe such additional conditions, illustrate why they are needed, and establish their sufficiency. We also consider a recent result by Malon [11] and demonstrate that, while the result itself is correct, its two proofs were incomplete. A complete proof of an extension of the result is then suggested. © 1995 John Wiley & Sons, Inc.  相似文献   
306.
This article defines and develops a simulation optimization system based upon response surface classification and the integration of multiple search strategies. Response surfaces are classified according to characteristics that indicate which search technique will be most successful. Typical surface characteristics include statistical measures and topological features, while search techniques encompass response surface methodology, simulated annealing, random search, etc. The classify-then-search process flow and a knowledge-based architecture are developed and then demonstrated with a detailed computer example. The system is useful not only as an approach to optimizing simulations, but also as a means for integrating search techniques and thereby providing the user with the most promising path toward an optimal solution. © 1995 John Wiley & Sons, Inc.  相似文献   
307.
Control charts are widely used for process surveillance. The design of a control chart refers to the choice of sample size, the width of the control limits, and the interval between samples. Economic designs have been widely investigated and shown to be an effective method of determining control chart parameters. This article describes two different manufacturing process models to which the X¯ control chart is applied: The first model assumes that the process continues in operation while searches for the assignable cause are made, and the second assumes that the process must be shut down during the search. Economic models of the control chart for these two manufacturing process models are developed, and the sensitivity of the control chart parameters to the choice of model is explored. It is shown that the choice of the proper manufacturing process model is critical because selection of an inappropriate process model may result in significant economic penalties.  相似文献   
308.
309.
310.
In this article we present some advanced basis or block-pivoting, relaxation, and feasible direction methods for solving linear programming problems. Preliminary computational results appear to indicate that the former two types of simplex-based procedures may hold promise for solving linear programming problems, unlike the third type of scheme which is shown to be computationally unattractive.  相似文献   
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