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91.
在全面总结韩国技术竞争情报(CTI)服务的兴起及发展历史的基础上,客观分析了其CTI应用的特点及其效果, 并且对韩国企业开展CTI活动的动力因素及其影响进行了深入研究.  相似文献   
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Children's experience of violence in China and Korea: a transcultural study   总被引:2,自引:0,他引:2  
Kim DH  Kim KI  Park YC  Zhang LD  Lu MK  Li D 《Child abuse & neglect》2000,24(9):1163-1173
OBJECTIVE: There were two aims: First, to compare children's rates of being battered in home, by peers, and by teachers among students between China and Korea, and second, to identify particular risk factors for such violence. METHODS: Children in grades four through six in Shanghai (238 cases) and Yanji (245 cases) in China and Seoul (248 cases) and Kimpo (241 cases) in Korea were surveyed by questionnaire method. They were asked to complete the Straus' Conflict Tactics Scale and their frequencies in the three situations respectively, and other demographic items. RESULTS: Family violence during the last 1 year was experienced in 70.6% (minor 42.2%; serious 22.6%) of the children in China and 68.9% (minor 9.4%; serious 51.3%) of those in Korea. Experience rates of violence by peers were 42.7% (minor 25.7%; serious 13.7%) in China and 26.0% (minor 11.5%; serious 14.3%) in Korea. Finally, rates of corporal punishment by teachers were 51.1% (minor 28.0%; serious 4.1%) in China and 62.0% (minor 8.8%; serious 43.8%) in Korea. The most important and common risk factor for violence in one situation was the presence of violence in another situation. CONCLUSIONS: The findings indicate that the differences in children's overall experience rates were not particularly striking. However, Korean children experienced more severe forms of violence from family members and from teachers. Findings of risk factors clearly imply that there are children vulnerable to violence from multiple sources.  相似文献   
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Particle focusing is an essential step in a wide range of applications such as cell counting and sorting. Recently, viscoelastic particle focusing, which exploits the spatially non-uniform viscoelastic properties of a polymer solution under Poiseuille flow, has attracted much attention because the particles are focused along the channel centerline without any external force. Lateral particle migration in polymer solutions in square channels has been studied due to its practical importance in lab-on-a-chip applications. However, there are still many questions about how the rheological properties of the medium alter the equilibrium particle positions and about the flow rate ranges for particle focusing. In this study, we investigated lateral particle migration in a viscoelastic flow of DNA solution in a square microchannel. The elastic property is relevant due to the long relaxation time of a DNA molecule, even when the DNA concentration is extremely low. Further, the shear viscosity of the solution is essentially constant irrespective of shear rate. Our current results demonstrate that the particles migrate toward the channel centerline and the four corners of a square channel in the dilute DNA solution when the inertia is negligible (elasticity-dominant flow). As the flow rate increases, the multiple equilibrium particle positions are reduced to a single file along the channel centerline, due to the elasto-inertial particle focusing mechanism. The current results support that elasto-inertial particle focusing mechanism is a universal phenomenon in a viscoelastic fluid with constant shear viscosity (Boger fluid). Also, the effective flow rate ranges for three-dimensional particle focusing in the DNA solution were significantly higher and wider than those for the previous synthetic polymer solution case, which facilitates high throughput analysis of particulate systems. In addition, we demonstrated that the DNA solution can be applied to focus a wide range of particle sizes in a single channel and also align red blood cells without any significant deformation.  相似文献   
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The purpose of this study was to examine which emergent literacy skills contribute to preschool children's emergent writing (name-writing, letter-writing, and spelling) skills. Emergent reading and writing tasks were administered to 296 preschool children aged 4-5 years. Print knowledge and letter-writing skills made positive contributions to name writing; whereas alphabet knowledge, print knowledge, and name writing made positive contributions to letter writing. Both name-writing and letter-writing skills made significant contributions to the prediction of spelling after controlling for age, parental education, print knowledge, phonological awareness, and letter-name and letter-sound knowledge; however, only letter-writing abilities made a significant unique contribution to the prediction of spelling when both letter-writing and name-writing skills were considered together. Name writing reflects knowledge of some letters rather than a broader knowledge of letters that may be needed to support early spelling. Children's letter-writing skills may be a better indicator of children's emergent literacy and developing spelling skills than are their name-writing skills at the end of the preschool year. Spelling is a developmentally complex skill beginning in preschool and includes letter writing and blending skills, print knowledge, and letter-name and letter-sound knowledge.  相似文献   
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The present study investigated relative contributions of initial status and growth rates of emergent literacy skills (i.e., phonological awareness, letter-name knowledge, vocabulary, and rapid serial naming) to initial status and growth rates of conventional literacy skills (i.e., word reading, pseudoword reading, and spelling) for young Korean children. A total of 215 four-year-old children were followed for approximately 15 months. Results showed (1) consistent effects of letter-name knowledge, phonological awareness, and rapid serial naming on conventional literacy skills, and (2) the importance of children’s initial level in the emergent literacy skills for achieving conventional literacy skills. These results are discussed in light of characteristics of the Korean language and writing system.  相似文献   
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This article reports on a two-year ethnographic study of learners participating in multi-site, graduate-level education classes. Classes sometimes met face-to-face in the same physical location; at other times part of the class met physically elsewhere. Yet all were linked through the virtual space. Ethnographic analysis of four data types explored how the instructor and students were able to interact through videoconferencing technologies. Most of the interaction occurred between the local and distance learners by way of cultural guides, local students assigned to host a distance learner through Google Video chat. The distance learners were able to receive real-time attention from the instructor and were able to share differing perspectives that contributed to increased satisfaction in the course. These interactions allowed for a dynamic collaborative effort among a diverse set of actors in the field of education.  相似文献   
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