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   446篇
  免费   1篇
  447篇
  2021年   11篇
  2019年   11篇
  2017年   11篇
  2016年   8篇
  2015年   11篇
  2014年   9篇
  2013年   91篇
  2010年   3篇
  2008年   5篇
  2007年   5篇
  2006年   4篇
  2005年   5篇
  2004年   3篇
  2003年   3篇
  2002年   6篇
  2001年   7篇
  2000年   4篇
  1999年   4篇
  1998年   8篇
  1997年   9篇
  1996年   6篇
  1995年   7篇
  1994年   9篇
  1993年   8篇
  1992年   7篇
  1991年   9篇
  1990年   3篇
  1989年   10篇
  1988年   17篇
  1987年   8篇
  1986年   15篇
  1985年   9篇
  1984年   6篇
  1983年   5篇
  1982年   5篇
  1981年   9篇
  1980年   5篇
  1979年   11篇
  1978年   7篇
  1977年   7篇
  1975年   9篇
  1974年   7篇
  1973年   5篇
  1972年   7篇
  1971年   5篇
  1970年   4篇
  1969年   6篇
  1968年   3篇
  1967年   3篇
  1966年   3篇
排序方式: 共有447条查询结果,搜索用时 0 毫秒
111.
Famous cultural monuments are often regarded as unique icons, making them an attractive target for terrorists. Despite huge military and police outlays, terrorist attacks on important monuments can hardly be avoided. We argue that an effective strategy to discourage terrorist attacks on iconic monuments is for a government to show a firm commitment to swift reconstruction. Using a simple game‐theoretic model, we demonstrate how a credible claim to rebuild any destroyed cultural monument discourages terrorist attacks by altering the terrorists' expectations and by increasing the government's reputation costs if they fail to rebuild.  相似文献   
112.
This paper aims at forecasting the burden on the Greek economy resulting from the arms race against Turkey and at concentrating on the leading determinants of this burden. The military debt and the defence share of GDP are employed alternatively in order to approximate the measurement of the arms race pressure on Greece, and the method used is that of artificial neural networks. The use of a wide variety of explanatory variables in combination with the promising results derived, suggest that the impact on the Greek economy resulting from this arms race is determined, to a large, extent, by demographic factors which strongly favour the Turkish side. Prediction on both miltary debt and defence expenditure exhibited highly satisfactory accuracy, while the estimation of input significance, indicates that variables describing the Turkish side are often dominant over the corresponding Greek ones.  相似文献   
113.
Abstract

This article surveys China’s current naval forces and considers key dynamics and possible Chinese naval futures to 2020, the projected end of Beijing’s ‘strategic window of opportunity’, the idea that a peaceful external environment for economic development, globalization, and integration of China into the global economy allows China to benefit from diversion of US attention to countering terrorism. It considers broad possibilities through 2030, the general limit of public US government projections, and by which time multiple factors will likely slow China’s growth and compete for leadership focus and resources.  相似文献   
114.
115.
116.
For the family D, consisting of those zero-sum two-person games which have a value, the value-function on D is characterized by four properties called objectivity, monotony, symmetry and sufficiency.  相似文献   
117.
Many optimization problems occur in both theory and practice when one has to optimize an objective function while an infinite number of constraints must be satisfied. The aim of this paper in to describe methods of handling such problems numerically in an effective manner. We also indicate a number of applications.  相似文献   
118.
In this article we present three properties that will improve the performance of branch-and-bound algorithms for fixed-cost transportation problems. By applying Lagrangian relaxation we show that one can develop stronger up and down penalties than those traditionally used and also develop a strengthened penalty for nonbasic variables. We also show that it is possible to “look ahead” of a particular node and determine the solution at the next node without actually calculating it. We present computational evidence by comparing our developments with existing procedures.  相似文献   
119.
Kanet addressed the problem of scheduling n jobs on one machine so as to minimize the sum of absolute lateness under a restrictive assumption on their common due date. This article extends the results to the problem of scheduling n jobs on m parallel identical processors in order to minimize the sum of absolute lateness. Also, a heuristic algorithm for a more general version with no restriction on the common due date, for the problem of n-job single-machine scheduling is presented and its performance is reported.  相似文献   
120.
Competitive imperatives are causing manufacturing firms to consider multiple criteria when designing products. However, current methods to deal with multiple criteria in product design are ad hoc in nature. In this paper we present a systematic procedure to efficiently solve bicriteria product design optimization problems. We first present a modeling framework, the AND/OR tree, which permits a simplified representation of product design optimization problems. We then show how product design optimization problems on AND/OR trees can be framed as network design problems on a special graph—a directed series‐parallel graph. We develop an enumerative solution algorithm for the bicriteria problem that requires as a subroutine the solution of the parametric shortest path problem. Although this parametric problem is hard on general graphs, we show that it is polynomially solvable on the series‐parallel graph. As a result we develop an efficient solution algorithm for the product design optimization problem that does not require the use of complex and expensive linear/integer programming solvers. As a byproduct of the solution algorithm, sensitivity analysis for product design optimization is also efficiently performed under this framework. © 2002 Wiley Periodicals, Inc. Naval Research Logistics 49: 574–592, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/nav.10031  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