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101.
102.
Effects of increment size and reinforcer volume on progressive ratio performance 总被引:11,自引:9,他引:2 下载免费PDF全文
The progressive ratio schedule requires the subject to emit an increasing number of responses for each successive reinforcement. Eventually, the response requirement becomes so large that the subject fails to respond for a period of 15 min and thereby terminates the session. This point is arbitrarily defined as the “breaking point” of the subject's performance. The measure is quantified in terms of the number of responses in the final completed (i.e., reinforced) ratio run of the session. Previous work has shown that this measure varies as a function of several motivational variables and may thus be useful as an index of reinforcement strength. The present study is an extension of that work. The subjects were four rats. In the first experiment, the effects of the size of the increment by which each ratio run increased were studied. In two additional experiments, the volume of a liquid reinforcer was varied using both large and small ratio increments. The results indicate that the number of responses in the final completed ratio run increases as a function of the size of the ratio increment. However, the number of reinforcements obtained by the animals per session declines sharply. When large ratio increments are used, the number of responses in the final ratio increases as a function of the volume of the reinforcer, but when small increments are used, progressive satiation results in a decline in performance with the larger volumes of liquid. 相似文献
103.
104.
3 groups of university freshmen took the SAT-V before and after a course in Accelerated Reading. The mean post-test scores for 2 groups increased slightly less than 10 points, while the mean post-test score for the third group decreased significantly. It is concluded that for the type of students used in this study, a course emphasizing speed and accuracy of reading is not of value in increasing scores on the verbal part of the Scholastic Aptitude Test. 相似文献
105.
In this paper we concern ourselves with the problem of whether or not conditioning stimuli of other modalities or stimuli applied to a distant locus of the body interact with a sensitive test of somesthetic temporal acuity we have called the gap test. The results of the experiment indicate that visual stimuli do not exert an observable influence on this temporal judgment, but that auditory stimuli and contralateral stimulation in the same modality do show a significant but relatively small effect. This is compared and contrasted with the very large and persistent effect reported when the conditioning stimulus is applied to the same electrodes as the gap test. By comparing our results with experiments of similar design carried out on lower animals by other investigators, some insights into the neural localization of the reported effects is obtained. 相似文献
106.
Preconditioning, with a burst of electrical pulse stimuli elevates the threshold for temporal acuity as measured with a technique requiring the S to detect a short gap in an otherwise regular burst of similar stimuli. Only a small amount of backward inhibition can be observed. The temporal duration of the inhibitory effect (up to 700 msec.) suggests that repetitive after-discharges of second-order afferents in Ike spinal cord may underlie this behavioral measure by actually filling in the intervals which are used by the S to make the judgment. The phenomenon is thus thought to be a disruption of a true temporal judgment rather than one indirectly mediated by an amplitude judgment, and as such it represents a significant datum on the temporal resolving power of time dimensions of neural coding. 相似文献
107.
William E. Kline 《Psychometrika》1959,24(4):343-359
A battery of 18 tests of intermediate algebra and 20 reference tests was administered to two successive second-year algebra classes. Each battery was separately factor analyzed by Thurstone methods, and the two analyses were synthesized by the Tucker method. The five congruent factors obtained were identified as: Verbal Comprehension, Deductive Reasoning, Algebraic Manipulative Skill, Number Ability, and Adaptability to a New Task.This paper is a condensation of a thesis. The work was begun while the author was a Psychometrics Fellow of the Educational Testing Service. The work was further supported by Contract N6onr-270-20 of the Office of Naval Research and by Grant NSF G-642 of the National Science Foundation. The writer is indebted to Professors Harold Gulliksen and Ledyard R Tucker for their guidance throughout this study. 相似文献
108.
William C. Schutz 《Psychometrika》1959,24(1):69-87
An exposition of a calculus for empirical classes (CEC), one of the few attempts by logicians to deal with the problem of constructs and indicators, is presented. The CEC provides the groundwork for a formal structure for the situation in which individuals have a degree of membership in various classes rather than having either membership or nonmembership—a situation nearly always true in empirical research. The CEC is presented and its relation to various social science concepts is mentioned. An application of the CEC model to latent structure analysis (LSA) suggests alternatives to the local independence assumption including one called the local scale assumption, which has a close relation to a Guttman scale. 相似文献
109.
110.
Auditory reaction time and the derivation of equal loudness contours for the monkey 总被引:4,自引:2,他引:2 下载免费PDF全文
William C. Stebbins 《Journal of the experimental analysis of behavior》1966,9(2):135-142
Monkeys were trained to release a telegraph key at the onset of a pure tone. Latency of the response was measured over a 70-db range of sound pressure (re 0.0002 dyn/cm(2)) at six frequencies (250 to 15,000 cps). Latency was found to be an inverse exponential function of intensity at all frequencies. Equal loudness was inferred from the equal latency contours which were constructed from the latency-intensity functions at each frequency. These data indicate peak auditory sensitivity for the monkey near 1000 cps. At the frequencies above and below 1000 cps consistently more sound energy was required for equal latency. 相似文献