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901.
In theory, not-for-profit organizations will be characterized by higher production costs per unit of output than for-profit producers of otherwise-identical goods/services, since profit maximization implies cost minimization per unit of output; breaking even does not imply cost minimization and, indeed, may imply inflated costs. We explore the empirical validity of this hypothesis in the context of higher education. Using 1996 data, we estimate multiproduct cost functions for 1,450 public, 1,316 private, not-for-profit, and 176 private, for-profit institutions of higher education in the United States. We fail to find a statistically significant difference between for-profit and not-for-profit private providers, but do find a statistically significant difference between private, not-for-profit institutions and public institutions.  相似文献   
902.
903.
This study investigates whether the generation of exploratory talk in grade seven, second-language science classrooms in the Eastern Cape Province, South Africa, has a positive effect on learners in terms of their problem-solving and reasoning skills and whether socio-cultural milieus (urban, peri-urban and rural settings of schools) have an effect on any cognitive gains that may be made by learners. The findings were that there is a clear and statistically significant improvement in the mean test scores on problem-solving and reasoning of pupils who participated in the classroom discussion initiative (exploratory talk) over those of the comparison groups. This result was consistent in both the first- and second-studies that were undertaken. There was also a significant difference between the gains in problem-solving and reasoning test scores of the three socio-geographical settings in which the participating schools are found.  相似文献   
904.
A two-part questionnaire was administered to 143 Head Start personnel in order to determine how personal characteristics of the Head Start workers and the characteristics of the families they serve, affect the identification and reporting of child maltreatment. Of additional interest was whether some forms of maltreatment, once identified, would be more likely to be reported than other forms of maltreatment. The results support the efficacy of educational programs in child maltreatment for increasing the identification and reporting of maltreatment by workers. They also indicate that there are complex interactions between certain characteristics of the reporter (e.g., educational level) and prior training in maltreatment identification. Finally, neglect, although more frequently identified by the workers, appears to be least likely of all forms of maltreatment to be reported to official sources. Results are discussed in light of their implications for future research and practical application.  相似文献   
905.
Journal of Science Education and Technology - Educators are now moving classroom instructional objectives away from what content do we need to know towards how can we support learners in the...  相似文献   
906.
The robustness of the effect of precise elaborations on memory and the relationship of these effects to metacognitions about learning was investigated in two studies. Twenty-six naive experimenters administered prepared tasks to 130 subjects. Participants rated the comprehensibility of each sentence as it was read. An unexpected cued-recall test with a confidence rating for each answer given was administered, followed by rating the ease of learning the types of items used in three treatments: precisely elaborated, imprecisely elaborated, and unelaborated base sentences. Both studies resulted in very similar findings: Memory for precise elaborations was 50% greater than for either imprecisely elaborated or unelaborated statements. Comprehension ratings of the three sets of statements were not significantly different. Confidence ratings of correctly answered items were significantly higher than of incorrectly answered items.  相似文献   
907.
The concepts of randomness and variation are pervasive in science. The purpose of this study was to document how post-secondary life science students explain randomness and variation, infer relationships between their explanations, and ability to describe and identify appropriate and inappropriate variation, and determine if students can identify sources of variation. An instrument designed to test statistical concepts was administered to 282 college students from three universities, ranging from introductory non-science majors to science graduate students. Students readily distinguished between causes of variation. A naïve no-pattern concept of randomness persisted from first-year non-science majors to senior-level science majors, contributing to incorrect responses on the variation instrument. Students’ expressions of randomness were better predictors of performance on the variation instrument than their expressions of variation. It is argued that inclusion of everyday language uses of randomness in instruction can bridge the gap between vernacular and scientific uses of this term.  相似文献   
908.
909.
In this paper we continue our search for a socially responsible science education by an examination of the trends in the Science, Technology and Society movement. These trends reflect differing ideological perspectives and result in courses which serve different ends. We identify two major flaws in the movement that inhibits the realization of a schooling in science dedicated to democracy. We propose skills necessary for citizens to participate in debate over issues surrounding the impact of science and technology on society and a teaching stategy to help develop them. Specializations: social responsibility and the curriculum, ideology and comparative science education.  相似文献   
910.
Widely cited experiments on optimal foraging have used bivalued distributions as representing environmental stochasticity, characterizing these in terms of their arithmetic means. In contrast, research on free-operant choice has established that organisms prefer variable patterns of food delivery, relative to fixed patterns with the same mean values. To explore such departures from linear averaging, specifically with respect to bivalued alternatives, pigeons were given choices between a fixed-ratio (FR) schedule of food delivery that required 15, 30, or 60 responses and bivalued variable-ratio schedules with an arithmetic mean of 60,5 or 60, A bivalued schedule of 1 and 120 was preferred almost exclusively over each of the FR values. With a bivalued schedule of 15 and 105, there was a shift of preference, most notably in the FR-15 condition, but in no case was linear averaging a good predictor of the birds’ choices. Geometric averaging fared better, but even this failed to represent the apparent salience of the minimum value of the bivalued schedule in some conditions.  相似文献   
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