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   58875篇
  免费   2387篇
  国内免费   18篇
  2020年   548篇
  2019年   734篇
  2018年   979篇
  2017年   1006篇
  2016年   1072篇
  2015年   781篇
  2014年   920篇
  2013年   4301篇
  2012年   1725篇
  2011年   1887篇
  2010年   1168篇
  2009年   1155篇
  2008年   1671篇
  2007年   1687篇
  2006年   1541篇
  2005年   1359篇
  2004年   1254篇
  2003年   1181篇
  2002年   1290篇
  2001年   1960篇
  2000年   1937篇
  1999年   1463篇
  1998年   681篇
  1997年   605篇
  1996年   605篇
  1993年   546篇
  1992年   1237篇
  1991年   1135篇
  1990年   1119篇
  1989年   1019篇
  1988年   1000篇
  1987年   956篇
  1986年   1025篇
  1985年   1041篇
  1984年   867篇
  1983年   780篇
  1982年   544篇
  1981年   550篇
  1979年   928篇
  1978年   658篇
  1975年   755篇
  1974年   810篇
  1973年   904篇
  1972年   766篇
  1971年   719篇
  1970年   639篇
  1969年   663篇
  1968年   851篇
  1967年   770篇
  1966年   650篇
排序方式: 共有10000条查询结果,搜索用时 281 毫秒
91.
A series of stereograms are presented which demonstrate that texture boundaries can strongly influence the perception of discontinuities between neighbouring three-dimensional (3-D) surfaces portrayed by means of stereo cues. In these demonstration figures, no stereo information is available in the immediate vicinity of the boundary between the two 3-D stereo surfaces because all texture in that region is removed in one eye's view. On the other hand, various forms of texture boundary information are provided in the resulting monocular region. This stimulus paradigm is used to explore the question: what influence does texture boundary information have on the nature of the perceived 3-D surface that is interpolated between two stimulus regions which carry stereo cues? It is shown that if a clear-cut texture boundary is present in the monocular region then this is used by the human visual system to fix the perceived location of 3-D crease and step surface discontinuities between the stereo regions. Collett (1985) explored this issue with a similar methodology and reported weak and unreliable assistance from monocular texture boundaries in helping shape 3-D stereo surface discontinuities. The strong and robust phenomena demonstrated here seem to rely on two main differences between the present stimuli and those of Collett. In the present stimuli, figurally continuous textures containing strong texture boundaries are used, together with a technique for minimising the complications, including binocular rivalry, that arise from the borders of the stimulus regions present in only one half of each stereogram.  相似文献   
92.
93.
This essay presents a philosophical and computational theory of the representation of de re, de dicto, nested, and quasi-indexical belief reports expressed in natural language. The propositional Semantic Network Processing System (SNePS) is used for representing and reasoning about these reports. In particular, quasi-indicators (indexical expressions occurring in intentional contexts and representing uses of indicators by another speaker) pose problems far natural-language representation and reasoning systems, because—unlike pure indicators—they cannot be replaced by coreferential NPs without changing the meaning of the embedding sentence. Therefore, the referent of the quasi-indicator must be represented in such a way that no invalid coreferential claims are entailed. The importance of quasi-indicators is discussed, and it is shown that all four of the above categories of belief reports can be handled by a single representational technique using belief spaces containing intensional entities. Inference rules and belief-revision techniques for the system ore also examined.  相似文献   
94.
Three factors that have transformed perceptual research in the last fifty years are the digital computer, single-unit electrophysiology, and molecular biology. Amongst the developments in which members of the Experimental Psychology Society have been central are: the recognition of the role of optic flow in spatial vision; the demonstration that our perceptual systems contain parallel pathways extracting different information from the sensory array; the identification of specific detectors that can be selectively adapted in psychophysical experiments; and the transfer of the concepts of fourier analysis from audition to vision. The history of Opponent Process Theory offers an example where experimental psychologists have been misled by too simple an interpretation of physiological recordings.  相似文献   
95.
96.
97.
98.
99.
Researchers have used multicomponent behavioral skills training packages including written and verbal instructions, modeling, rehearsal, and feedback when teaching caregivers to implement pediatric feeding treatment protocols (e.g., Anderson & McMillan, 2001; Seiverling et al., 2012). Some investigators have shown that fewer behavioral skills training components may be necessary for effective training (e.g., Mueller et al., 2003; Pangborn et al., 2013). We examined the use of in-vivo feedback following written instructions to train caregivers to implement pediatric feeding treatment protocols using a multiple baseline design across 3 caregiver dyads. Correct implementation of the feeding treatment procedures was low during baseline (written instructions only), increased with only the addition of in-vivo feedback, and remained high during follow-up sessions for all caregivers. Results are discussed in terms of clinical implications and caregiver satisfaction.  相似文献   
100.
Social Psychology of Education - Attitudes toward ethnic and racial identity have been linked to both wellbeing and maladaptive outcomes that affect belonging at school. Further, relatedness (or...  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