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131.
This paper describes a computational method for weighted euclidean distance scaling which combines aspects of an analytic solution with an approach using loss functions. We justify this new method by giving a simplified treatment of the algebraic properties of a transformed version of the weighted distance model. The new algorithm is much faster than INDSCAL yet less arbitrary than other analytic procedures. The procedure, which we call SUMSCAL (subjectivemetricscaling), gives essentially the same solutions as INDSCAL for two moderate-size data sets tested.Comments by J. Douglas Carroll and J. B. Kruskal have been very helpful in preparing this paper. 相似文献
132.
133.
A simple method for producing audio tapes with temporally synchronized messages is described. The duration and spacing of words can be precisely controlled. This method requires a minimum of elaborate equipment, yet synchronization is very accurate with highly intelligible speech. 相似文献
134.
Carol L Smith 《Journal of experimental child psychology》1980,30(2):191-205
Two hypotheses were tested about how young children answer questions with the quantifiers all and some: (a) that children use syntactic cues in determining which noun phrase is quantified, and (b) that children evaluate a some-statement as part of evaluating an all-statement. To test these hypotheses, the same group of 60 4- to 7-year-olds were asked four contrasting types of quantitative questions. The results indicated that children can use syntactic cues under some presentation conditions. However, there was no evidence for an asymmetry between the all-and some-questions. A model of how young children might answer quantitative questions was then considered. 相似文献
135.
Sandra Haber 《Sex roles》1980,6(1):129-138
The career aspirations of 50 female college seniors of lower- and middle-class backgrounds was assessed by a questionnaire and tape-recorded interview. Using a fourfold classification contrasting career choice with career commitment, the women were classified as innovative career oriented, innovative noncareer oriented, traditional career oriented, and traditional noncareer oriented. The career aspirations of these women, however, were not related to maternal employment patterns as previous studies have indicated. Rather, the perceived attitudes and direction of the parents was found to be a significant correlate of career choice and career commitment. It was concluded that maternal employment as a modeling variable may be unimportant for women of lower- and middle-class backgrounds.This article is based on a dissertation which was submitted in partial fulfillment of the requirements for the Ph.D. degree in the Graduate Center, City University of New York. The author expresses appreciation to Dr. Florence Denmark for her continuous support throughout the entire study and also thanks Dr. Bernard Seidenberg for his valuable suggestions on earlier drafts of this article. 相似文献
136.
137.
Ronald S. Harwerth Earl L. Smith Dennis M. Levi 《Attention, perception & psychophysics》1980,27(1):43-50
Binocular interactions of suprathreshold grating patterns have been investigated using a reaction time measure of contrast detection. Simple reaction times were determined for monocular and binocular viewing conditions over a contrast range from .63 to near threshold. The results from all subjects showed binocular summation for contrast levels near threshold, but there was considerable variation across subjects for contrast levels above threshold. Some subjects showed summation over the entire contrast range, but other subjects showed either binocular inhibition or binocular facilitation for some range of contrast levels. The pattern of binocular interaction for a given subject was consistent for several spatial frequencies. The differences in types of interaction between subjects, the variation in magnitude of binocular interaction with contrast level for each subject, and the data from experiments involving stimulation of noncorresponding retinal areas show that the binocular interactions found for suprathreshold stimuli cannot be accounted for on the basis of probability, and must, therefore, result from physiological interactions between the two eyes. These interactions have been investigated further under conditions of (1) induced fixation disparity, (2) horizontal gratings, and (3) orthogonally oriented gratings. 相似文献
138.
Developments in television technology have made possible new approaches to the study of the role of visual feedback in motor control. In two experiments using a special videodisc recording and playback system, the effects of delaying for 66 msec a subject's view of his own hand during a target-directed movement was investigated. The observed effects of such visually delayed feedback compared to spatially distorted feedback produced by prisms led to three major conclusions: (a) despite the behavioral similarity (overshooting) induced by the two kinds of altered feedback, the role of each in the visual-motor control loop is different; (b) adaptation to and the after effect of the two kinds of altered feedback are based on different control mechanisms (c) the processing and use of visual information in hand control requires less time than previous experiments have indicated. 相似文献
139.
Three experiments are described that studied the role of detailed graphemic analysis upon the ability to read text. College students named letters in various approximations to English, with frequency of individual letters constant. Findings were that later skill at reading varied with the order of approximation to English of the letters that were named, that the spacing of the letter sequences was important to this result, and, finally, that the influence of specific visual practice extended to the typeface on which the naming and reading were carried out. Hence, rather than a letter-by-letter process or its opposite, a wholly semantic analysis, reading is shown to be intimately dependent upon details of visual analysis of patterns or letter sequences. 相似文献
140.
Bruce L Smith 《Brain and language》1980,10(1):89-97
Audio recordings of the speech of seven patients receiving cortical stimulation during epilepsy surgery were acoustically analyzed, and duration measurements of the sound /s/ under stimulation and nonstimulation conditions were compared. It was found that in the dominant hemisphere, stimulation tended to significantly increase the duration of /s/; but not all stimulation sites were comparably affected. Stimulation of frontal lobe locations was also observed to more frequently result in durational increases than when temporal or parietal sites were stimulated. However, for sites affected, the actual magnitude of durational increase was comparable among the three lobes. 相似文献