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   388篇
  免费   6篇
  2021年   7篇
  2019年   7篇
  2018年   5篇
  2017年   3篇
  2016年   7篇
  2014年   5篇
  2013年   63篇
  2012年   3篇
  2009年   4篇
  2008年   2篇
  2007年   13篇
  2005年   2篇
  2004年   3篇
  2003年   7篇
  2002年   6篇
  2001年   3篇
  2000年   3篇
  1999年   4篇
  1998年   7篇
  1997年   8篇
  1996年   9篇
  1995年   3篇
  1994年   6篇
  1993年   10篇
  1992年   8篇
  1991年   9篇
  1990年   13篇
  1989年   17篇
  1988年   14篇
  1987年   7篇
  1986年   14篇
  1985年   8篇
  1984年   4篇
  1983年   3篇
  1982年   10篇
  1981年   6篇
  1980年   7篇
  1979年   9篇
  1978年   8篇
  1977年   5篇
  1976年   5篇
  1975年   5篇
  1974年   8篇
  1973年   5篇
  1972年   3篇
  1971年   7篇
  1970年   6篇
  1969年   5篇
  1967年   5篇
  1948年   4篇
排序方式: 共有394条查询结果,搜索用时 15 毫秒
101.
We consider the problem of searching for a target that moves in discrete time and space according to some Markovian process. At each time, a searcher attempts to detect the target. If the searcher's action at each time is such as to maximize his chances of immediate detection, we call his strategy “myopic.” We provide a computationally useful necessary condition for optimality, and use it to provide an example wherein the myopic strategy is not optimal.  相似文献   
102.
In military situations of sharply increasing combat activity the Marine Corps is faced with training problems in its expanding aviator corps. Additional training aircraft are required, and procurement decisions must be made. In view of the significant costs involved in procurement and operation of new high performance aircraft, it is very desirable to buy and operate an efficient mix of aircraft necessary for training the pilots to make the Marine Aircraft Wings essentially 100-percent tactically qualified. The mathematical model presented here enables computation of a least-cost mix of training aircraft which satisfies certain specified training requirements. The basic element allowing tradeoffs is the commonality of training available in the F4, RF4, A6, and EA6 types of aircraft. Both airframe oriented and mission oriented training are necessary, but the airframe oriented training can be conducted in either of the aircraft possessing the commonality. Training requirements over a five year period are considered, and the mix of training aircraft has the minimum five year procurement and operating cost.  相似文献   
103.
This paper discusses the operations analysis in the underwater search for the remains of the submarine Scorpion The a priori target location probability distribution for the search was obtained by monte-carlo procedures based upon nine different scenarios concerning the Scorpion loss and associated credibility weights. These scenarios and weights were postulated by others. Scorpion was found within 260 yards of the search grid cell having the largest a priori probability Frequent computations of local effectiveness probabilities (LEPs) were carried out on scene during the search and were used to determine an updated (a posteriori) target location distribution. This distribution formed the basis for recommendation of the current high probability areas for search The sum of LEPs weighted by the a priori target location probabilities is called search effectiveness probability (SEP) and was used as the overall measure of effectiveness for the operation. SEP and LEPs were used previously in the Mediterranean H-bomb search On-scene and stateside operations analysis are discussed and the progress of the search is indicated by values of SEP for various periods during the operation.  相似文献   
104.
Several approximate procedures are available in the literature for obtaining confidence intervals for the parameter A of an exponential distribution based on time truncated samples. This paper contains the results of an empirical study comparing three of these procedures.  相似文献   
105.
The present article considers a problem of missile warfare. It is formulated as a problem of economics and treated as a differential game. Some optimal strategies of targeting and firing of missiles are derived. Conditions under which such a war can be prevented are also developed.  相似文献   
106.
A statistic is determined for testing the hypothesis of equality for scale parameters from two populations, each of which has the first asymptotic distribution of smallest (extreme) values. The probability distribution is derived for this statistic, and critical values are determined and given in tabular form for a one-sided or two-sided alternative, for censored samples of size n1 and n2, n1 = 2, 3, …. 6, n2 = 2, 3, …. 6. The power function of the test for certain alternatives is also calculated and listed in each case considered.  相似文献   
107.
108.
109.
The objective of this article is to describe heuristic solutions to the problem of modeling inventories at each node of a large network in the context of a computer simulation model of that network. The heuristic solutions are compared with the mathematical solution which is too unwieldy for use in a simulation model. The Weibull cumulative distribution is used as an approximation for the heuristic models. We question whether the good performance of the Weibull is coincidence or perhaps mathematically justifiable.  相似文献   
110.
在我们十分敬仰的老总长粟裕同志诞辰100周年之际,我们怀着无比崇敬的心情,深切缅怀他的丰功伟绩和崇高风范,以寄托我们不尽的思念.粟裕同志是久经考验的共产主义战士、无产阶级革命家和杰出的军事家,是新中国军事领率机关建设的主要奠基人之一.  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