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   985篇
  免费   84篇
  2023年   12篇
  2021年   7篇
  2020年   43篇
  2019年   9篇
  2018年   15篇
  2017年   37篇
  2016年   40篇
  2015年   29篇
  2014年   43篇
  2013年   131篇
  2012年   46篇
  2011年   33篇
  2010年   31篇
  2009年   48篇
  2008年   40篇
  2007年   30篇
  2006年   28篇
  2005年   27篇
  2004年   24篇
  2003年   26篇
  2002年   31篇
  2001年   14篇
  2000年   18篇
  1999年   11篇
  1998年   11篇
  1997年   11篇
  1996年   14篇
  1995年   10篇
  1994年   18篇
  1993年   10篇
  1992年   14篇
  1991年   16篇
  1990年   10篇
  1989年   11篇
  1988年   12篇
  1987年   15篇
  1986年   14篇
  1985年   10篇
  1984年   7篇
  1983年   7篇
  1982年   9篇
  1981年   17篇
  1980年   7篇
  1979年   8篇
  1978年   11篇
  1977年   16篇
  1976年   5篇
  1974年   10篇
  1970年   3篇
  1956年   3篇
排序方式: 共有1069条查询结果,搜索用时 15 毫秒
31.
The perception of distance and size in the presence of optical gradient information was investigated under four viewing conditions—binocular view with and without head motion, and monocular view with and without head motion. Subjects (60 adults) matched distance intervals (from 15 to 127 cm) and heights of a target triangle (from 5 to 15 cm) by adjusting the length of a metal tape. Both linear and power functions were fitted to each individual’s distance judgments, and the competing perceptual models were compared. For both models, it was found that binocular information was sufficient to specify relative, but not absolute, distance, that monocular information was sufficient to specify an orderly relation between target distance and judgment but not absolute distance, that average error was less in the binocular conditions, and that perceived distance was not affected in either condition by the addition of head motion. The analysis of size judgments revealed that monocular and binocular judgments did not differ, that matches made with and without head motion did not differ, and that, in all conditions, matches exceeded target heights by an average 30% to 40%. Judged size was also analyzed as a function of target distance. In all conditions but monocular view with head motion, the effect of distance was to increase size judgments. The distance judgments support the hypothesis (Purdy, 1958) that the binocular stimulus carries information that the monocular stimulus does not; they fail to support the hypothesis (Gibson, 1966) that observer motion adds information to the static stimulus. The size judgments support neither hypothesis but suggest an independence of perceived size from perceived distance.  相似文献   
32.
33.
34.
35.
Reliable monitoring of the movement of small aquatic animals presents some unique problems. In the case of the larval salamander, the animal may be less than an inch long and move in sporadic short bursts. A device is described that utilizes infrared emitters and wide-band sensors inter-faced to a computer for monitoring location and movement of animals between light and dark environments over extended periods of time. The system employs a multiplexed digital input, is inexpensive, and can be easily expanded to deal with a range of monitoring problems that may occur with a wide range of both aquatic and terrestrial species.  相似文献   
36.
A limited national sample of 49 school psychologists and 30 regular education teachers provided information on assessment for the purpose of instructional planning. School psychologists listed the types of information they most often collected for this purpose and teachers listed the types of information considered most useful for this purpose. While some indications of agreement were found between school psychologists and teachers, there were also several inconsistencies in the views of the two groups regarding assessment procedures for instructional planning. The findings are discussed in light of empirical evidence on the contribution of various types of assessment data to instructional planning.  相似文献   
37.
Previous research has shown that perceived odor strength does not vary with flow rate of an odorant vapor entering the naris when that variation is produced by subject-controlled changes in sniff pressure, but that it does vary with flow rate when the variation is produced by experimenter-controlled changes in the resistance of the olfactometric system. We have suggested an odor-constancy model in which invariance of perceived odor strength is linked to perceived effort of sniffing, and have hypothesized that changed resistance will have its effect because there is no corresponding change in perceived effort when sniff pressure is held constant. In two studies, subjects made magnitude estimations of the perceived effort of sniffing; sniff pressure was controlled by having the subject match his sniff, displayed on a storage oscilloscope face, to a pattern specifying its required shape, duration, and level. In Experiment 1, resistance was fixed while sniff pressure varied; perceived effort grew as the .8 power of the required sniff pressure. In Experiment 2, sniff pressure and resistance were varied in a factorial design; perceived effort grew as the .8 power of pressure at fixed resistance, but remained unchanged when resistance varied at fixed pressure. This outcome provides indirect support for the odor-constancy model, since it shows that perceived effort covaries with flow rate under the condition in which constancy is found but does not change under the condition in which constancy fails.  相似文献   
38.
Summary Following an abrupt shift from a therapeutic community with emphasis on group meetings to a hierarchical medical model on a mental hospital floor, disturbed patients required extensive individual nursing care. This increased work load for the nursing staff resulted in admissions having to be limited to the rare cases who needed little or no nursing care. As patients were discharged, the vacancy rate went up to approximately 20% for a week and remained high for another two weeks. Nursing staff-patient relations deteriorated.Subsequently, it was possible to resume the emphasis on the groups of a therapeutic community and to observe the contrast. The experience showed how groups can effect and support a therapeutic community. It clarified some of the mechanisms by which groups positively affected disturbed patients. Some mechanisms by which the staff, community, and group meetings favorably influenced the nursing staff-patient relationship and intrastaff communications became clear also.  相似文献   
39.
The study reports relationships between teachers' belief systems (Harvey), a teacher-pupil interaction measure of classroom influence, pupils' perception of the dimate of the dassroom, and pupils' academic achievement. Results demonstrate that more complex teachers encourage more pupil influence, and are perceived as having a more origin climate. In classrooms of high pupil influence and perceived origin climate, the pupils have higher academic achievement. These results are discussed in terms of the theory of personal causation and are cited as evidence for the value of the study of action sequences as related to verbal-utterances of the actors.  相似文献   
40.
The investigation analyzed the phonemic paraphasic errors of 10 asphasic patients with posterior cerebral lesions. The results indicated that paraphasic speech is characterized by complex confusions, often occurring at the ends of words and often involving phonemic transpositions. Many of the unusual and unexpected phonemic errors appeared to be due to simultaneous semantic and phonologic confusions.  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