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   46404篇
  免费   1597篇
  国内免费   19篇
  2020年   445篇
  2019年   461篇
  2018年   628篇
  2017年   722篇
  2016年   738篇
  2015年   533篇
  2014年   628篇
  2013年   3403篇
  2012年   1204篇
  2011年   1277篇
  2010年   801篇
  2009年   794篇
  2008年   1139篇
  2007年   1074篇
  2006年   971篇
  2005年   907篇
  2004年   859篇
  2003年   831篇
  2002年   902篇
  2001年   1342篇
  2000年   1332篇
  1999年   974篇
  1998年   482篇
  1997年   430篇
  1992年   873篇
  1991年   809篇
  1990年   852篇
  1989年   834篇
  1988年   773篇
  1987年   756篇
  1986年   798篇
  1985年   866篇
  1984年   702篇
  1983年   652篇
  1982年   483篇
  1981年   512篇
  1979年   763篇
  1978年   568篇
  1977年   507篇
  1976年   478篇
  1975年   716篇
  1974年   793篇
  1973年   789篇
  1972年   707篇
  1971年   658篇
  1970年   607篇
  1969年   689篇
  1968年   798篇
  1967年   765篇
  1966年   731篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Ss judged average heaviness of two unseen lifted weights on a 20-step rating scale. They also rated heaviness of a single visible object of variable size and weight. The data for each task obeyed the parallelism prediction of the linear integration model. This within-task consistency validates jointly the model and the response scale. Functional measurement procedure yielded independent scales of subjective heaviness from each task. These were linearly related, a criterion of external consistency. The plot of subjective heaviness against objective weight was slightly negatively accelerated. These results disagree with those that have been obtained with magnitude estimation. Since the rating data satisfy both internal and external consistency, they constitute the true measure of sensation. Magnitude estimation, in contrast, must be biased and invalid.  相似文献   
992.
The effects of backward masker “fringe” on performance in homophasic and antiphasic masking conditions were investigated. The results of the study indicate that (1) the presence of a backward masker fringe has only a small effect on performance in homophasic masking conditions; (2) under antiphasic masking conditions, the presence of a backward masker fringe improves performance; (3) similar to the results of studies investigating the effects of forward masker fringe, the magnitude of the improvement in performance increases as the duration of the fringe increases; and (4) the magnitude of the improvement caused by the presence of backward masker fringe is considerably smaller than the magnitude of the improvement caused by the forward masker fringe. It appears, then, that the presence of backward masker fringe may provide a baseline or reference phase similar to that which the forward fringe is presumed to provide. The presence of this reference phase after the offset of the signal apparently makes the phase shift associated with the signal-plus-noise waveform more discernible, thus leading to higher detectability. However, for reasons not yet clear, the presence of a baseline or reference phase after the offset of the signal (backward fringe conditions) does not make the signal-plus-noise phase shift as discernible as do either the presence of that same reference phase before the onset of the signal (forward fringe condition) or the presence of that same reference phase both before signal onset and after signal offset (continuous masker condition).  相似文献   
993.
A variation of the method of graded dichotomies was used to obtain judgments of interstimulus similarity for all pairings of 21 12-turn random shapes. Using the Tucker-Messick procedure, a six-dimensional spatial model, representing individual variation in performance on the task, was derived. Six “idealized individuals” (IIs) were isolated. A five-dimensional Euclidean spatial model was obtained for each II using the Shepard-Kruskal scaling technique. The resulting psychological dimensions of perceived form were related to two sets of physical measures on the forms: the factor space suggested by Brown and Owen and a set of more basic physical measures. These basic measures allowed interpretation of most of the psychological dimensions and revealed differences between IIs in patterns of cue utilization.  相似文献   
994.
995.
Sustained behavioral contrast in children   总被引:1,自引:1,他引:0       下载免费PDF全文
Children were exposed to a multiple schedule involving equal variable-interval schedules in each of two components and a multiple schedule involving a variable-interval schedule in one component and an extinction schedule in the other. Response rates were equal in both components when each involved a variable-interval schedule. Response rates differed in the two components of the multiple variable-interval extinction schedule. Response rates were higher in the variable-interval schedule when the accompanying schedule was extinction than when it was variable interval. The increase in response rate in the variable-interval component, simultaneous with the decrease in response rate in the extinction component, illustrated sustained behavioral contrast, and was the first evidence of this phenomenon in children.  相似文献   
996.
Rats trained to lever press on a fixed-interval limited-hold avoidance schedule maintained a pattern of responding similar to that maintained by fixed-interval limited-hold schedules of positive reinforcement. But this positively accelerated pattern of behavior was maintained only when the occurrence of reinforcement was signalled by the presentation of a brief flash of light. This result suggests that the discriminative function of the reinforcer in avoidance is less pronounced than the discriminative function of the reinforcer in escape or positive reinforcement. It also suggests that the distinction between positive reinforcement and avoidance is not superfluous. Although the schedule of reinforcement is an important variable in determining the pattern of behavior, other variables, such as the nature (i.e., stimulus presentation, termination, or omission) of the reinforcer, are also potent determinants of behavior.  相似文献   
997.
Zusammenfassung Parks Kritik beruht, meiner Ansicht nach, auf einem entscheidenden Mißverständnis meiner Intentionen: es geht mir überhaupt nicht um eine Argumentation gegen eine Transformationsgrammatik à la Chomsky, und nicht einmal in erster Linie gegen die Absicht mancher Psycholinguisten, eine derartige Theorie in ihren psychischen Funktionen aufzuzeigen. Ich möchte lediglich dafür plädieren, daß die Psycholinguistik in erster Linie psychologische (und nicht linguistische) Überlegungen und Modellvorstellungen als Leitlinien verwendet.  相似文献   
998.
An ann-out-of-water response was conditioned as an operant inOctopus cyaneus Gray. The response was limited to a vertical tube, 2.54 em i.d, Photoresistive sensors, illuminated with modulated light arranged around the tube above the waterline, detect the presence of an opaque object in the tube. The signal from this response detector is amplified and used to initiate a commercial motor-driven universal feeder according to the reinforcement schedule maintained by the logic control circuit. A sample cumulative record for perfonnance on a CRF schedule is given.  相似文献   
999.
Modifications of the Hewlett-Packard version of the BASIC language to permit its use in data acquisition and control of on-line experiments are described. The resulting software system is an easy-to-use interpretative compiler.  相似文献   
1000.
Errors in a serial choice-reaction time experiment employing two-finger chord responses to alphabetic stimuli are shown to be distributed in a significantly non-random fashion. Two factors are postulated which are relevant to prediction of the error response. These are the presence or absence of a common finger, and the difference in finger separation, between the actual and the required response. It is suggested that the chord response is coded in terms of a pattern (the distance between the two response components). Responses which mirror the correct response about the centre of the hand are also shown to be significantly more frequent.  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