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941.
942.
A variety of theorists have proposed that individuals desire to be confident in their inferences and predictions. One way this can be accomplished is by overestimating the extent to which available information provides a logic basis for such conclusions. Thus, when one's goal is to make an accurate prediction, if information about a prior known instance has potential implications for the prediction, one may overestimate the similarity of the prior known instance to the current instance. In this way, the perceived utility of the information as a basis for prediction can be inflated. To test this idea, three studies were conducted. In each study, subjects were asked to judge the similarity of past instances to an upcoming instance for which an outcome prediction was required. Judging a past instance as similar to the upcoming instance should only provide a firm basis for outcome prediction if outcome information regarding the past instance is known. Therefore, it was expected that when subjects are asked to make an outcome prediction, they would judge a past instance more similar to the upcoming instance if outcome information about the past instance is known than if it is not. Support for this hypothesis was obtained along with evidence concerning the conditions under which the eflect does and does not occur.  相似文献   
943.
Tuck  Bryan  Rolfe  Jan  Adair  Vivienne 《Sex roles》1994,31(9-10):547-558
Sex Roles - Information was obtained from 184 females and 157 males enrolled in grade 11 in six urban high schools. The majority of the students were of European descent (70%), but there were...  相似文献   
944.
Historically, unaccompanied Southeast Asian refugee adolescents have been inadequately served by mental health professionals. The authors of this article report research findings on self-perceived depression and isolation and implications for psychotherapy. Results indicate significant differences regarding sex, English language skills, work involvement, and self-disclosure.  相似文献   
945.
In two experiments, the active haptic identification of three-dimensional mathematically welldefined objects is investigated. The objects, quadric surfaces, are defined in terms of the shape index, a quantity describing the shape, and curvedness, a quantity describing overall curvature. Both shape index and curvedness are found to have a significant influence on haptic shape identification . Concave surfaces lead to a larger spread in responses than convex ones. Hyperbolic surfaces show a slight tendency to be identified with more difficulty than elliptic ones. Surfaces with a high curvedness are identified more easily than those with a low curvedness. Results from experiments with constant and with random curvedness are indistinguishable . It is concluded that shape index and curvedness are psychophysically not confounded.  相似文献   
946.
We asked subjects to match points on the surface of a smooth three-dimensional (3-D) shape with points on the surface of another object that was geometrically identical to the first object but was placed in a different pose, was differently textured, and was differently shaded. In all cases, the fiducial point was on the rim of one of the objects (i.e., the boundary of the visible region of the surface), whereas the matching point was well within the silhouette of the other object. This allowed us to draw (preliminary) conclusions concerning the way monocular human observers are able to handle the neighborhood of the rim, where the local slant assumes arbitrarily high values. All experiments were done in real space with real objects (no computer-simulated scenes), the points being indicated with laser beam illumination. The subject was given control over the direction of the laser beams and was thus able to perform the task by adjustment from the vantage position. We studied both consistency (whether the subject’s judgments were invariant against changes of relative pose) and veridicality (whether the depth of the visual contour as calculated from the settings agreed with the true distance as measured by mechanical means). Subjects caught much of the 3-D structure of the contour but did deviate appreciably and apparently idiosyncratically from the true geometry.  相似文献   
947.
We investigated the extent to which the human visual system can detect discontinuities in firstorder optical flow fields. We constructed two types of spatial discontinuities: a circular split field with a straight edge and a disk with annular surround. We used two different first-order optical flow components: an expansion and a rotation. We found an intriguing difference in the detection thresholds for straight and circular discontinuities. Whereas straight discontinuities yielded thresholds of 10%— 50% difference in expansion or rotation, circular discontinuities could, at first, only be detected at extreme differences (>>100%). After a learning period, thresholds for such stimuli decreased, but they remained significantly higher than thresholds for the straight edge. Thresholds rose for stimuli that formed a gradual transition between a circular and a straight edge, and they decreased with increasing eccentricity of the circular discontinuity. Results suggest that symmetry in the stimulus, defined by the coincidence of the center of expansion or rotation and the center of the circular discontinuity, was responsible for the difference in thresholds for circular and straight discontinuities.  相似文献   
948.
949.
Four odor substances (lemon aroma, rum aroma, ethyl butyrate, and amyl acetate) in different concentrations were presented nasally and orally (retronasally) in a four-alternative forced-choice procedure (detection tasks). In a further experimental condition, sucrose was added to the stimuli. Finally, the taste properties of the (nonsugared) odor stimuli were judged on seven semantic scales. In the detection of odor-containing stimuli, there were no significant differences between nasal and retronasal stimulation. In the taste conditions, however, there was a significant decline of “hits” when the stimuli contained sucrose in addition to the odor substances. Furthermore, in semantic scaling of the taste stimuli, a new variant of the taste-smell illusion was observed, namely, a tendency to attribute “suited” basic taste categories (e.g., “sweet”) to pure (nongustatory) odor stimuli.  相似文献   
950.
A total of 200 residents of Columbus, Ohio, were questioned over the telephone about their knowledge of U.S. and Soviet crisis relocation plans, their feelings about chances of surviving nuclear attack, and their behavioral intentions in the event of an evacuation. Few respondents displayed knowledge of the existence or substance of crisis relocation plans. Most gauged survival rates in the event of a nuclear attack as substantially higher with an evacuation plan than without one, but in both cases expectations were that fewer than 50% of the population would survive. While most respondents stated they would follow evacuation procedures, evidence of possible noncompliance was found.  相似文献   
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