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   9839篇
  免费   252篇
  10091篇
  2024年   56篇
  2023年   72篇
  2022年   53篇
  2021年   113篇
  2020年   184篇
  2019年   240篇
  2018年   290篇
  2017年   341篇
  2016年   359篇
  2015年   270篇
  2014年   289篇
  2013年   1089篇
  2012年   499篇
  2011年   507篇
  2010年   307篇
  2009年   301篇
  2008年   397篇
  2007年   404篇
  2006年   329篇
  2005年   359篇
  2004年   343篇
  2003年   305篇
  2002年   290篇
  2001年   156篇
  2000年   168篇
  1999年   148篇
  1998年   119篇
  1997年   104篇
  1996年   116篇
  1995年   106篇
  1994年   87篇
  1993年   80篇
  1992年   103篇
  1991年   89篇
  1990年   86篇
  1989年   69篇
  1988年   75篇
  1987年   62篇
  1986年   70篇
  1985年   82篇
  1984年   82篇
  1983年   70篇
  1982年   81篇
  1981年   76篇
  1980年   58篇
  1979年   64篇
  1978年   57篇
  1977年   79篇
  1975年   52篇
  1973年   50篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
11.
Feature integration theory has recently been revised with two proposals that visual conjunction search can be parallel under some circumstances—either because items with nontarget features are inhibited, or because items with target features are excited. We examined whether excitatory or inhibitory guidance controlled conjunction search for an X oscillating in one direction among Os oscillating in that direction and Xs oscillating in another. Search was affected by whether items oscillated in phase with each other, and it was exceptionally difficult when items with target motion moved out of phase with each otherand items with nontarget motion moved out of phase. The results suggest that conjunction search can be guided both by excitation of target features and by inhibition of nontarget features.  相似文献   
12.
Peter Turney 《Synthese》1989,79(3):515-542
The logic of scientific discovery is now a concern of computer scientists, as well as philosophers. In the computational approach to inductive inference, theories are treated as algorithms (computer programs), and the goal is to find the simplest algorithm that can generate the given data. Both computer scientists and philosophers want a measure of simplicity, such that simple theories are more likely to be true than complex theories. I attempt to provide such a measure here. I define a measure of simplicity for directed graphs, inspired by Herbert Simon's work. Many structures, including algorithms, can be naturally modelled by directed graphs. Furthermore, I adapt an argument of Simon's to show that simple directed graphs are more stable and more resistant to damage than complex directed graphs. Thus we have a reason for pursuing simplicity, other than purely economical reasons.This paper is based on part of my doctoral dissertation. Thanks to my thesis supervisor Professor Alasdair Urquhart for his encouragement, constructive criticism, and for directing me to several relevant articles; to my advisor, Professor Ian Hacking, for reminding me to concentrate on results that might have some application in the real world; to Professor Eric Mendelsohn for checking my use of graph theory; and to my friend Wendy Brandts for sharing her ideas on a closely related problem.Thanks to my friends and family (the latter being a (proper) subset of the former, and both including Dr. Louise Linney, of course) for ongoing support in my scholastic endeavors.Thanks to the Social Sciences and Humanities Research Council for financial assistance. (Awards 452-86-5885 and 453-87-0513.) Thanks to the University of Toronto for financial assistance.  相似文献   
13.
It was a coincidence that I was asked to talk about resistance at Ground Rounds at the University of Texas, Department of Psychiatry, on the tenth anniversary of mailing the first version of Death of Resistance to a journal in 1979. Although the paper was subsequently rejected 17 times and revised six times, it was eventually published inFamily Process (de Shazer, 1984). I still insist that the concept of resistance was a bad idea for therapists to have in their heads.This paper was presented April 14, 1989, at Ground Rounds, University of Texas, Southwest Medical Center, Department of Psychiatry, Dallas, Texas.  相似文献   
14.
In this paper, 1 describe psychological guidelines for simplifying medical information — methods to aid the perception and recognition of abnormalities in medical test reports. These techniques resemble natural human editing strategies outlined in prospect theory. The methods pre-edit data as humans do but to reduce human effort. I review empirical studies assessing these techniques and discuss needs for further research.  相似文献   
15.
16.
Although there has been a considerable amount of research on simultaneous and successive processing (Luria's second functional unit) by Das and others, there have been relatively few investigations into the measurement of attention and planning (the first and third functional units, respectively). The purpose of this investigation was to examine the factorial validity of tasks designed to measure cognitive processing in each of Luria's three functional units. A sample of 112 normal fourth- and fifth-grade students were administered nine experimental tasks chosen or developed according to the theoretical components of planning, attention, simultaneous, and successive processes. Principal factor analyses (orthogonal and oblique) with rotation of four factors resulted in solutions that closely matched the anticipated groupings based on a structural analysis of the tasks. General support for the feasibility of measurement of Luria's cognitive processing model, and the need to further develop and refine these and other experimental tasks, was obtained.  相似文献   
17.
18.
An investigation was conducted to examine how individuals choose situations in which to initiate relationships. It was hypothesized that individuals' self-monitoring orientation and the characteristics of their relationship partners would interact to determine situation choices. Accordingly, low- and high-self-monitoring men were asked to rate their preferences for interacting in romantic and nonromantic situations with particular types of partners. The characteristics of the partners were varied along two dimensions: physical attractiveness and personality desirability. Results demonstrated that low-, relative to high-, self-monitoring individuals' preferences for interacting in romantic situations were more influenced by the personality characteristics of potential partners. In contrast, high-, relative to low-, self-monitoring individuals' preferences for interacting in romantic situations were more influenced by the physical attractiveness of potential partners. Neither of these effects occurred when preferences for nonromantic situations were assessed. Implications of these differences for the initiation, maintenance, and dissolution of relationships were discussed.  相似文献   
19.
D A de Rosenroll 《Adolescence》1987,22(88):791-802
This paper reviews six articles which appear to be representative of the past fifteen years during which researchers have focused on early adolescent egocentrism. Each article is described in chronological order and compared to research findings suggested by the other articles. Although the researchers have suggested some interesting associations, there is a lack of consistency among their findings. The author indicates methodological problems and questions for further research which arise from the reviewed articles.  相似文献   
20.
The purpose of this note is to formulate some weaker versions of the so called Ramsey test that do not entail the following unacceptable consequenceIf A and C are already accepted in K, then if A, then C is also accepted in K. and to show that these versions still lead to the same triviality result when combined with a preservation criterion.  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