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   189篇
  免费   0篇
  2023年   2篇
  2019年   2篇
  2018年   2篇
  2017年   5篇
  2016年   3篇
  2015年   2篇
  2014年   2篇
  2013年   46篇
  2012年   1篇
  2011年   1篇
  2009年   3篇
  2008年   4篇
  2007年   2篇
  2006年   1篇
  2004年   4篇
  2003年   2篇
  2002年   6篇
  2001年   2篇
  2000年   2篇
  1999年   3篇
  1998年   3篇
  1997年   4篇
  1996年   3篇
  1995年   6篇
  1994年   5篇
  1993年   4篇
  1992年   5篇
  1991年   6篇
  1990年   4篇
  1989年   2篇
  1987年   4篇
  1986年   4篇
  1985年   5篇
  1984年   2篇
  1983年   3篇
  1982年   4篇
  1981年   2篇
  1980年   3篇
  1978年   1篇
  1977年   1篇
  1976年   2篇
  1975年   2篇
  1974年   4篇
  1973年   3篇
  1972年   2篇
  1971年   1篇
  1970年   1篇
  1969年   3篇
  1968年   1篇
  1967年   2篇
排序方式: 共有189条查询结果,搜索用时 187 毫秒
21.
A method is presented to locate and allocate p new facilities in relation to n existing facilities. Each of the n existing facilities has a requirement flow which must be supplied by the new facilities. Rectangular distances are assumed to exist between all facilities. The algorithm proceeds in two stages. In the first stage a set of all possible optimal new facility locations is determined by a set reduction algorithm. The resultant problem is shown to be equivalent to finding the p-median of a weighted connected graph. In the second stage the optimal locations and allocations are obtained by using a technique for solving the p-median problem.  相似文献   
22.
Suppose that a contractor is faced with a sequence of “minimum bid wins contract” competitions. Assuming that a contractor knows his cost to fulfill the contract at each competition and that competitors are merely informed whether or not they have won, bids may be selected sequentially via a tailored stochastic approximation procedure. The efficacy of this approach in certain bidding environments is investigated.  相似文献   
23.
24.
25.
Person-borne improvised explosive devices (PBIEDs) are often used in terrorist attacks in Western countries. This study aims to predict the trajectories of PBIED fragments and the subsequent safety risks for people exposed to this hazard. An explosive field test with a typical PBIED composed of a plastic explosive charge and steel nut enhancements was performed to record initial fragment behaviour, including positions, velocity, and trajectory angles. These data were used to predict the full trajectory of PBIED fragments using a probabilistic analysis. In the probabilistic analyses a probability of fatality or serious injury was computed. Based on the results presented, many practical conclusions can be drawn, for instance, regarding safe evacuation distances if a person were exposed to a suspected PBIED.  相似文献   
26.

Plunder and trade are theoretically and historically entwined in complex ways. This paper examines when rational players will choose one or both by employing a model of plunder within an evolutionary game theoretic framework. Evolutionary stable strategy equilibria are derived and the replicator dynamics are examined for simple two-by-two symmetric games. Not only are positive defense allocations necessary for trade, implying that all trade is of a contested nature, but the defense technology must also exhibit sufficient effectiveness relative to the plunder technology. A continuum of possible exchanges is proposed that is based on the effectiveness of enforcing property claims. For high levels of transactions costs, plunder dominates. As transactions costs decline, mutual trade emerges as one possible exchange mechanism. All market exchange entails some cost of enforcement; it is contested. Insufficient enforcement of property claims produces mutual plunder as the dominant exchange mechanism. Some implications are suggested for institutional evolution. C7 K4 N4  相似文献   
27.
Book reviews     
Jurgen Brauer's comment presents what he calls a replication of an earlier study by Higgs and Kilduff (1993) and uses it to criticize the adequacy of the Higgs‐Kilduff model. In several respects, however, Brauer has not actually performed a replication: he uses different data, a different sample period, and arrives at different results. His criticisms rest on his own setup, not that of Higgs and Kilduff. Therefore they have no strict applicability to the latter. Moreover, Brauer's stepwise model has no bearing on the Higgs‐Kilduff model, as it violates that model's specification requirements.  相似文献   
28.
We have used the Michigan Model of World Production and Trade to assess the impact of exports and imports of armaments (based on 1980 data) on sectoral trade and employment and other economic variables in the major Western trading countries. If the United States were to place a unilateral embargo on its arms exports and imports, we calculate that it would experience a comparatively small amount of employment displacement in the aggregate and that most of this displacement would occur in the transport equipment and electric machinery sectors. If all the major Western countries were to place a multilateral embargo on their arms trade, the sectoral effects on the United States would be similarly small. But the sectoral effects in several other industrialized and developing countries measured as a percentage of sectoral employment, would be larger, indicating potential short‐run adjustment problems in labor markets in some cases.  相似文献   
29.
Standard economic concepts of production and cost minimization subject to a production constraint are used to derive the conditions of optimal deployment of home and forward military forces for the production of home security. United States' participation in the NATO alliance is then analyzed in the context of a two‐ally (U.S. and Western Europe) optimal force deployment model of NATO. Next, U.S. force‐basing policy is adduced as an enforcement mechanism for the “transatlantic contract.” Lastly, statistical evidence on burden sharing within Western Europe, and the effectiveness of the U.S. contract enforcement policy, is presented.  相似文献   
30.
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