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   1364篇
  免费   73篇
  2024年   2篇
  2023年   15篇
  2022年   25篇
  2021年   28篇
  2020年   37篇
  2019年   40篇
  2018年   93篇
  2017年   94篇
  2016年   64篇
  2015年   36篇
  2014年   34篇
  2013年   167篇
  2012年   79篇
  2011年   122篇
  2010年   64篇
  2009年   39篇
  2008年   82篇
  2007年   60篇
  2006年   54篇
  2005年   47篇
  2004年   38篇
  2003年   34篇
  2002年   31篇
  2001年   15篇
  2000年   11篇
  1999年   20篇
  1998年   5篇
  1997年   11篇
  1996年   7篇
  1995年   3篇
  1994年   12篇
  1993年   5篇
  1992年   7篇
  1991年   4篇
  1990年   2篇
  1989年   5篇
  1988年   2篇
  1987年   4篇
  1985年   5篇
  1982年   2篇
  1981年   6篇
  1980年   2篇
  1976年   2篇
  1974年   4篇
  1972年   2篇
  1968年   2篇
  1965年   2篇
  1964年   1篇
  1963年   1篇
  1962年   2篇
排序方式: 共有1437条查询结果,搜索用时 31 毫秒
1.
2.
3.
In this paper, an attempt is made to solve various problems posed to current theories of verisimilitude: (1) the (Miller's) problem of linguistic variance; (2) the problem of which are the best scientific methods for getting the most verisimilar theories; and (3) the question of the ontological commitment in scientific theories. As a result of my solution ot these problems, and with the help of other considerations of epistemological character, I conclude that the notion of Tarskian truth is dispensable in a rational (and realist) interpretation of the scientific enterprise. As a logical result, however, falsificationism will be vindicated.
... and in brief, a speaker must always aim at verisimilitude, and send the truth packing.
Plato,Phaedrus, 272 EI want to express my gratitude to Professors García-Bermejo, Niiniluoto, and Zofío for interesting comments and critiques of several of the ideas in this paper, and to Miss Karen Firnich for correcting my English. I am also thankful to an anonymous referee who indicated several dark points on a previous version of my article.  相似文献   
4.
The continuous approach to optic-flow processing shows that the curvature of a moving surface is related to a second spatial derivative of the velocity field, the spin variation (Droulez & Cornilleau-Pérès, 1989). With this approach as a theoretical framework, visual sensitivity to the curvature of a cylinder in motion was measured using a task of discrimination between cylindrical and planar patches. The results confirm the predictions suggested by the theory: (1) Sensitivity to curvature was always greater when the cylinder axis and the frontal translation were parallel than when they were orthogonal. The ratio of curvature detection thresholds in the two cases was between 1.3 and 2.5; the value predicted from the spin variation theory is about 2. (2) Sensitivity to curvature increased strongly with the velocity of the motion but was only weakly affected by its amplitude and the duration of viewing for the range of values used in our experiments.  相似文献   
5.
Ås, A. Non-hypnotic experiences related to hypnotizability in male and female college students. Scand. J. Psychol ., 1962, 3 , 112–131.—Some recent research on the relation between subjective experiences and hypnotic susceptibility is reviewed. In a male sample of 50 subjects significant correlations between scores on the Experience Inventory and hypnotizability were found. A cross-validation of composite experience scores on this sample and a female sample studied earlier gave positive results. Based on several sources of data a preliminary analysis is made of the similarities and differences between male and female students regarding experiences related to hypnotizability.  相似文献   
6.
In this paper a method is outlined for measuring the diversity of the results of applied R&D with the use of IPC (International Patent Classification). The method has been tested in the contexts of the academic physical, engineering, and chemical institutes. The trend of applied research at a given institute increases both at the level of classes and subclasses, and at the IPC level. Inventions developed within specializations at each institute have a greater efficiency than other forms of inventive activity. The objective was to seek the optimal extent of diversification of applied R&D, which would simultaneously ensure the preservation of the scientific specialization of an institute, the high level of scientific research associated with developing innovations, and the high overall efficiency of each institute.  相似文献   
7.
Finland has followed the Scandinavian model of the welfare state in which the level of state activism is high, the economic pressures on the scientific activities are strong, and the left-wing parties and the Center Party have formulated the main ideas. In the 1970s welfare ideology was adopted in science policy by emphasizing the promotion of socially relevant scientific activities and the expansion of the university system as a means of effecting equal opportunity. Currently, the trend is toward a mixed welfare economy. Programs have been prepared in spite of the radical cut in government expenditure, and without a consideration of the long-term consequences.  相似文献   
8.
When an observer views a moving scene binocularly, both motion parallax and binocular disparity provide depth information. In Experiments lA-1C, we measured sensitivity to surface curvature when these depth cues were available either individually or simultaneously. When the depth cues yielded comparable sensitivity to surface curvature, we found that curvature detection was easier with the cues present simultaneously, rather than individually. For 2 of the 6 subjects, this effect was stronger when the component of frontal translation of the surface was vertical, rather than horizontal. No such anisotropy was found for the 4 other subjects. If a moving object is observed binocularly, the patterns of optic flow are different on the left and right retinae. We have suggested elsewhere (Cornilleau-Pérès & Droulez, in press) that this motion disparity might be used as avisual cue for the perception of a 3-D structure. Our model consisted in deriving binocular disparity from the left and right distributions of vertical velocities, rather than from luminous intensities, as has been done in classical studies on stereoscopic vision. The model led to some predictions concerning the detection of surface curvature from motion disparity in the presence or absence of intensity-based disparity (classically termedbinocular disparity). In a second set of experiments, we attempted to test these predictions, and we failed to validate our theoretical scheme from a physiological point of view.  相似文献   
9.
10.
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