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561.
Keypecking of pigeons was studied under differential-reinforcement-of-low-rate (DRL) and variable-interval (VI) schedules in which the interreinforcement times on the two schedules were equated by a yoking procedure. Each schedule was available for half of every session and a change of schedule was signaled by a change of key color. The value of the DRL schedule was varied from .5 to 300 sec. Response rates were always higher in the VI schedule, but within sessions there was a sharp change in response rate coincident with the change in schedule only under lower schedule values. A group without prior training was tested with a 180-sec schedule value, and it, too, developed a higher response rate during the VI schedule, showing that the effect was not dependent on prior experience under low schedule values. In all conditions except the .5- and 1-sec values of the schedule, the mean proportion of responses emitted during the VI schedule was approximately .85 of the responses emitted during both schedules. The conclusion was that the requirement of a minimum interresponse time for reinforcement may work its effect by determining which responses may occur just prior to the reinforced response and thus receive delayed reinforcement.  相似文献   
562.
Six desert iguanas (Dipsosaurus dorsalis) were trained on a black-white discrimination problem using a modified Lashley maze I. The results, in terms of number of trials to criterion, compared favorably to those reported for turtles on the same brightness difference. Efficiency of learning was attributed to (1) the angle separating the discriminanda, (2) intertrial substrate temperature, and (3) visual attentional characteristics of the apparatus. In addition, orienting responses (VTE) varied in expected directions according to speed of learning and difficulty of maze choice points.  相似文献   
563.
A short version of the Approaches to Studying Inventory (ASI), commended as a ‘quick and easy’ means of assessing student learning, was administered to two groups of students at the University of the South Pacific. Measures of its internal consistency and test‐retest reliability were comparable with those obtained in European research, but were not wholly satisfactory. Moreover, its factor structure was found to be qualitatively different in this context and constituted by different forms of motivation for studying in higher education. It is concluded that approaches to studying are culture‐specific and, in particular, that one should be cautious about using this version of the ASI in systems of higher education in non‐Western countries.  相似文献   
564.
This experiment tests the hypothesis that background, adult television is a disruptive influence on very young children's behavior. Fifty 12-, 24-, and 36-month-olds played with a variety of toys for 1 hr. For half of the hour, a game show played in the background on a monaural TV set. During the other half hour, the TV was off. The children looked at the TV for only a few seconds at a time and less than once per minute. Nevertheless, background TV significantly reduced toy play episode length as well as focused attention during play. Thus, background television disrupts very young children's play behavior even when they pay little overt attention to it. These findings have implications for subsequent cognitive development.  相似文献   
565.
The primary purpose of the present study was to assess the ontogeny of nonassociative learning and memory in 16-, 30-, and 75-day-old rats. In each of three experiments, habituation of the orienting response to a novel auditory stimulus was measured. The orienting response is an unconditioned reaction elicited by innocuous environmental stimulation that habituates with repeated stimulus presentations. Both an autonomic component (heart-rate deceleration) and a behavioral index (head jerk) of the orienting response were recorded in this study. Although no age differences in rate of habituation (i.e., rate of nonassociative learning) were found (see Experiment 1), a marked effect of age on retention of habituation was observed. Preweanling rats retained habituation of the orienting response to an auditory stimulus for less than 4 h (Experiment 2), whereas adult animals exhibited no forgetting even after a 1-week interval (Experiment 3). These results are discussed in terms of (1) demonstrations of age-related differences in associative memory, (2) the persistence of nonassociative memories in adults, and (3) the significance of the orienting response as a measure of retention of nonassociative learning.  相似文献   
566.
OBJECTIVE: A cross-sectional study of gender specific relationships between self-reported child sexual abuse and suicidality in a community sample of adolescents. METHOD: Students aged 14 years on average (N = 2,485) from 27 schools in South Australia completed a questionnaire including items on sexual abuse and suicidality, and measures of depression (Centre for Epidemiological Studies Depression Scale), hopelessness (Beck Hopelessness Scale), and family functioning (McMaster Family Assessment Device General Functioning Subscale). Data analysis included logistic regression. RESULTS: In boys, self-report sexual abuse is strongly and independently associated with suicidal thoughts, plans, threats, deliberate self-injury, and suicide attempts, after controlling for current levels of depression, hopelessness, and family dysfunction. In girls, the relationship between sexual abuse and suicidality is mediated fully by depression, hopelessness, and family dysfunction. Girls who report current high distress about sexual abuse, however, have a threefold increased risk of suicidal thoughts and plans, compared to non-abused girls. Boys who report current high distress about sexual abuse have 10-fold increased risk for suicidal plans and threats, and 15-fold increased risk for suicide attempts, compared to non-abused boys. Fifty-five percent (n = 15) of sexually abused boys attempted suicide versus 29% (n = 17) girls. CONCLUSIONS: A history of sexual abuse should alert clinicians, professionals and carers in contact with adolescents, to greatly increased risks of suicidal behavior and attempts in boys, even in the absence of depression and hopelessness. Distress following sexual abuse, along with depression and hopelessness indicate increased risk of suicidal behavior in girls, as well as boys.  相似文献   
567.
Conceptions of learning in adult students embarking on distance education   总被引:1,自引:0,他引:1  
A 60-item questionnaire on conceptions of learning was mailed to students taking preparatory courses by distance learning with The Open University in the United Kingdom. Complete data were provided by 372 respondents. Their scores on six factor-based scales showed satisfactory internal consistency, cluster analysis identified five groups of students with distinct patterns of scores, and discriminant analysis identified the scales that served to distinguish among the clusters. Three groups had conceptions of learning based on critical thinking, personal development, and personal change, but the other groups had conceptions that were defined in largely negative terms. Adult learners embarking on distance education seem to hold distinctive conceptions of learning, which suggests that conceptions of learning are culturally and contextually dependent.  相似文献   
568.
We investigated motivation for taking low stakes tests. Based on expectancy-value theory, we expected that the effect of student perceptions of three task values (interest, usefulness, and importance) on low stakes test performance would be mediated by the student’s reported effort. We hypothesized that all three task value components would play a significant role in predicting test-taking effort, and that effort would significantly predict test performance. Participants were 1005 undergraduate students enrolled at four midsize public universities. After students took all four subtests of CBASE, a standardized general education exam, they immediately filled out a motivation survey. Path analyses showed that the task value variables usefulness and importance significantly predicted test-taking effort and performance for all four tests. These results provide evidence that students who report trying hard on low stakes tests score higher than those who do not. The results indicate that if students do not perceive importance or usefulness of an exam, their effort suffers and so does their test score. While the data are correlational, they suggest that it might be useful for test administrators and school staff to communicate to students the importance and usefulness of the test that they are being asked to complete.  相似文献   
569.
It is unclear how children develop the ability to learn words incidentally (i.e., without direct instruction or numerous exposures). This investigation examined the early achievement of this skill by longitudinally tracking the expressive vocabulary and incidental word-learning capacities of a hearing child of Deaf adults who was natively learning American Sign Language (ASL) and spoken English. Despite receiving only 20% of language input in spoken English, the child's expressive vocabularies at 16 and 20 months of age, in each language, were similar to those of monolingual age-matched peers. At 16 months of age, the child showed signs of greater proficiency in the incidental learning of novel ASL signs than she did for spoken English words. At 20 months of age, the child was skilled at incidental word learning in both languages. These results support the methodology as it applies to examining theoretical models of incidental word learning. They also suggest that bilingual children can achieve typical vocabulary levels (even with minimal input in one of the languages) and that the development of incidental word learning follows a similar trajectory in ASL and spoken English.  相似文献   
570.
Primary objective. To examine perceptions of academic quality and approaches to studying in students taking six technology courses by distance education.

Research design. Students taking four courses received an end-of-course questionnaire. The following year, students taking all six courses received a mid-course questionnaire.

Method. The Course Experience Questionnaire and the Revised Approaches to Studying Inventory were administered in a postal survey to 3539 students of the UK Open University.

Outcomes and results. Across successive levels of study, students were progressively less likely to adopt a deep approach, were more likely to adopt a surface approach and rated their courses less favourably, especially with regard to the workload and materials. Between the middle and end of a course, students were more likely to adopt a deep approach and gave more positive ratings with regard to the materials and amount of choice.

Conclusions. The survey instruments can be recommended as useful tools for monitoring the experiences of engineering and technology students.  相似文献   

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