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121.
We use eye tracking as a method to examine how different mathematical representations of the same mathematical object are attended to by students. The results of this study show that there is a meaningful difference in the eye movements between formulas and graphs. This difference can be understood in terms of the cultural and social shaping of human perception, as well as in terms of differences between the symbolic and graphical registers.  相似文献   
122.

Objective:

The research tested the accuracy of the VIVO Harvester software in identifying publications authored by faculty members affiliated with a National Institutes of Health Clinical and Translational Sciences Award (CTSA) site.

Methods:

Health sciences librarians created “gold standard” lists of references for the years 2001 to 2011 from PubMed for twenty-five randomly selected investigators from one CTSA site. These gold standard lists were compared to the same twenty-five investigators'' reference lists produced by VIVO Harvester. The authors subjected the discrepancies between the lists to sensitivity and specificity analyses.

Results:

The VIVO Harvester correctly identified only about 65% of the total eligible PubMed references for the years 2001–2011 for the CTSA-affiliated investigators. The identified references produced by VIVO Harvester were precise yet incomplete. The sensitivity rate was 0.65, and the specificity rate was 1.00.

Conclusion:

While the references produced by VIVO Harvester could be confirmed in PubMed, the VIVO Harvester retrieved only two-thirds of the required references from PubMed. National Institutes of Health CTSA sites will need to supplement VIVO Harvester–produced references with the expert searching skills of health sciences librarians.

Implications:

Health sciences librarians with searching skills need to alert their CTSA sites about these deficiencies and offer their skills to advance their sites'' missions.  相似文献   
123.
This investigation reports the effects of chewing caffeinated gum on race performance with trained cyclists. Twenty competitive cyclists completed two 30-km time trials that included a maximal effort 0.2-km sprint each 10-km. Caffeine (~3–4 mg · kg?1) or placebo was administered double-blind via chewing gum at the 10-km point following completion of the first sprint. Measures of power output, oxygen uptake, heart rate, lactate and perceived exertion were taken at set intervals during the time trial. Results indicated no substantial differences in any measured variables between caffeine and placebo conditions during the first 20-km of the time trial. Caffeine gum did however lead to substantial enhancements (mean ± 90% confidence limits (CLs)) in mean power during the final 10-km (3.8% ± 2.3%), and sprint power at 30-km (4.0% ± 3.6%). The increases in performance over the final 10-km were associated with small increases in heart rate and blood lactate (effect size of 0.24 and 0.28, respectively). There were large inter-individual variations in the response to caffeine, and apparent gender related differences in sprint performance. Chewing caffeine gum improves mean and sprint performance power in the final 10-km of a 30-km time trial in male and female cyclists most likely through an increase in nervous system activation.  相似文献   
124.
Designing public policies using information technology as a communication support system is one of the most important current issues in the public policy making field. This work presents a methodology for the design and selection of public policies based on the cognitive democratic model known as e-Cognocracy. In addition to facilitating debate between representatives and the represented (deliberative democracy), this model allows for co-decision making between citizens and politicians. Furthermore, and of even greater importance, e-Cognocracy generates a process of continuing education that is concordant to the lifelong process of living systems (cognitive process). The methodology contemplates multiple rounds (usually two) when incorporating the preferences of the actors implicated in decision making and takes advantage of the creative capacity of human beings when solving complex problems. At the same time, the methodology permits the evaluation of both the individual and social learning that is derived from the scientific resolution of the problem and the democratisation of the knowledge that is extracted. This methodology was applied to a real-life experience in the Spanish municipality of Cadrete.  相似文献   
125.
Although the environmental light/dark cycle is the main zeitgeber for the human species, the social cues seem to be important in the synchronization of circadian rhythms. In Brazil, the existence of two school schedules—one with only morning classes (MG) and other with only afternoon classes (AG)—allows the investigation of the effect of school activities on light exposure and sleep/wake patterns in children. Forty‐seven children wore wrist actimeters for a week for registration of light and sleep data. MG children presented shorter sleep duration on school days than the children from the AG. The results showed that during school days MG children were exposed to bright light earlier in the morning when compared to AG children. Nevertheless, there were no differences in light exposure after sunset. The results reflect the role of school schedules and artificial light in shaping light exposure, and its association with sleep timing in children.  相似文献   
126.
Ethics and Information Technology - During the last decade there has been burgeoning research concerning the ways in which we should think of and apply the concept of responsibility for Artificial...  相似文献   
127.
The use of Web 2.0 technologies for knowledge management is invading the corporate sphere. The Web 2.0 is the most adopted knowledge transfer tool within knowledge intensive firms and is starting to be used for mentoring. This paper presents IM-TAG, a Web 2.0 tool, based on semantic technologies, for informal mentoring. The tool offers recommendations of mentoring contents built upon personal competencies of the mentee, combined with content and opinion tagging. To validate the tool, a case study comparing recommendations from the IM-TAG and a group of experts was conducted. Results show that the accuracy of IM-TAG's recommendations is notable and satisfactory. The main conclusions of this research may be valuable to organizations immersed in mentoring programs.  相似文献   
128.
Brazil is a huge country with at least 100 million readers with a total population of 200 million. Is this a good number for you? The article describes the developments of the Brazilian book market and publishing industry. Sales in 2009 were an estimated $2.5 billion for more than 228 million copies of books sold. But a country this big, as it is almost 50% of entire South America, confronts several major challenges including a real lack of bookstores. But one of the channels that is growing every year are the door-to-door sales, it has grown from 5% of all sales in 2006 to 17% in 2009. In a country this big, the digital or eBooks may also be a very good strategy to get to more readers, but it is still a small market in Brazil. The interesting news is that publishers are working on it and looking for solutions and ways to act on this new area of digital and online publishing.  相似文献   
129.
The paper describes the numerical techniques implemented in the finite-element code NOSA for structural analysis of masonry constructions. The code is then applied to the analysis of “Buti’s bell tower”, a medieval structure located on the Pisa mountains, under two different conditions: firstly, with the structure subjected to its own weight alone, and then while subjected to both its own weight and a horizontal load, which models an earthquake. The displacement and stress fields, as well as the distribution of cracking have been calculated with NOSA, and the numerical results analysed and compared to the actual distribution of fractures in the tower.  相似文献   
130.
This study investigated how the age of entry into regular group day care may influence, in the context of other relevant variables, some short-time outcomes of this experience. In particular the study focused on behaviours expressing well-being or discomfort in the day care environment during the third year. Subjects were 129 young children who were enrolled in group day care when they were 6–29 months old. During their third year their social behaviour was evaluated by caregivers with the Day Care Adaptation Scale. Researchers observed 54 of the children in reunion with their parents. The quality of care was rated with the ITERS scale. It was found that children who started day care in the intervals 6–12 months and 18–23 months displayed more frequently difficult reunions with their mothers, and were rated as less resistant to frustration. Children who started day care from 12–17 months showed lower relational distress. Some significant relationships were found between the ratings of ITERS and the Day Care Adaptation Scale. These findings are discussed with reference to theories of attachment.  相似文献   
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