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101.
Although there have been efforts to define, describe, and classify business models, current literature does not provide a structured method of comparing business models between companies within or between industries. This article outlines a conceptual business model and proposes 5 components that a business model for content delivery should include: the product, the consumer, the revenue, the price, and the delivery. By using the newspaper and magazine industry as an example, we empirically test the impact of these 5 components on profit. Furthermore, we address 2 key issues content providers are confronted with when selling digital content: First, how much of the digital content is available free or at cost, and second, is the digital product as complementary or a substitute to the physical product. Finally, we assess the risk of cannibalizing the physical product with the digital one by a multiple regression analysis. 相似文献
102.
Is your library market-driven, product-driven or customer-driven? New internet-based data and tools are now available for public libraries that enable you to be customer-driven—for your own unique service area. This article shows how three library systems are using these tools—focused on market segmentation data and geographic information system (GIS) technology—to deliver more relevant customer services. Each solution described in the article was developed in close collaboration between CIVICTechnologies and the library, involving research to understand the library's objectives and desired outcomes, and using the data needed to meet each library's unique challenge. 相似文献
103.
Vladimir Vilde Marc Fourneau Catherine Charles Daniel Van Vlaender Julie Bouhy Yves Poumay 《文物保护研究》2013,58(5):284-297
ABSTRACTThe preservation state of parchment primarily depends on the structure of the collagen fibre network, which in turn is responsible for optical anisotropy, i.e. birefringence. Polarised light microscopy can therefore be used as a non-invasive technique that allows recording of birefringence distribution in the parchment, which directly relates to stress–strain distribution. Using samples from diverse sources (commercial parchment, parchment used by restorers for book binding, and parchment fabricated for the purpose of this study), we assessed the capability of polarised light microscopy for various diagnostics. We performed, for instance, identification of gelatinised regions, layered or ?brous regions in parchment cross section, qualitative analysis of parchment fat content (lipids), observation of stress-induced patterns resulting from tensile tests, and observation of water diffusion. These proof-of-principle experiments extend the capability of polarised light microscopy far beyond its common use and open the path to its deployment in conservation studies. 相似文献
104.
Dr. Morgan discusses the recommended content of economics courses, describes several significant projects in economics education, and provides sources from which teachers may obtain complete reports of these projects. 相似文献
105.
Although molecular-level details are part of the upper-secondary biology curriculum in most countries, many studies report that students fail to connect molecular knowledge to phenomena at the level of cells, organs and organisms. Recent studies suggest that students lack a framework to reason about complex systems to make this connection. In this paper, we present a framework that could help students to reason back and forth between cells and molecules. It represents both the general type of explanation in molecular biology and the research strategies scientists use to find these explanations. We base this framework on recent work in the philosophy of science that characterizes explanations in molecular biology as mechanistic explanations. Mechanistic explanations describe a phenomenon in terms of the entities involved, the activities displayed and the way these entities and activities are organized. We conclude that to describe cellular phenomena scientists use entities and activities at multiple levels between cells and molecules. In molecular biological research, scientists use heuristics based on these intermediate levels to construct mechanistic explanations. They subdivide a cellular activity into hypothetical lower-level activities (top-down approaches) and they predict and test the organization of macromolecules into functional modules that play a role in higher-level activities (bottom-up approaches). We suggest including molecular mechanistic reasoning in biology education and we identify criteria for designing such education. Education using molecular mechanistic reasoning can build on common intuitive reasoning about mechanisms. The heuristics that scientists use can help students to apply this intuitive notion to the levels in between molecules and cells. 相似文献
106.
Süleyman Turşucu Jeroen Spandaw Steven Flipse Marc J. de Vries 《International Journal of Science Education》2013,35(5):587-604
ABSTRACTStudents in senior pre-university education encounter difficulties in the application of mathematics into physics. This paper presents the outcome of an explorative qualitative study of teachers’ beliefs about improving the transfer of algebraic skills from mathematics into physics. We interviewed 10 mathematics and 10 physics teachers using a semi-structured questionnaire that was based on an algebraic transfer problem. Almost all teachers acknowledged this transfer problem and considered it to be important. We found a continuum of teachers’ beliefs about aspects influencing transfer, including beliefs on improving this transfer. Together with identified improvement aspects about coherent mathematics education, these may help reduce physics teachers’ frustrations who spend extra time on re-teaching mathematics. Teachers think that transfer does not happen, because students see both subjects as separate disciplines. Contrary to most physics teachers, most mathematics teachers do not feel the need to collaborate with physics teachers. We found two extreme, opposite beliefs about the transfer of algebraic skills into physics. An intermediate group believes that only an integrated approach can solve the transfer problem. Some of the teachers’ beliefs could be organised into a beliefs system. Further research could investigate to which extent such beliefs systems exist and which beliefs these contain. 相似文献
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Elena Bender Peter Hubwieser Niclas Schaper Melanie Margaritis Marc Berges Laura Ohrndorf 《Peabody Journal of Education》2013,88(4):519-532
To address the special challenges of teaching computer science, adequate development of teachers’ competencies during their education is extremely important. In particular, pedagogical content knowledge and teachers’ beliefs and motivational orientations play an important role in effective teaching. This research field has been sparsely investigated up to now and there exists no consistent competency model for teaching computer science in Germany. Therefore, this paper describes the development of competency in the areas of pedagogical content knowledge, teachers’ beliefs, and motivational orientations with regard to computer science. Competency-relevant factors for teaching computer science are theoretically derived and concretely formulated with the help of expert interviews conducted according to the critical incident technique and analyzed using techniques of qualitative content analysis. 相似文献
110.
This study explored how neighborhood characteristics may relate to African American adolescents' internalizing symptoms via adolescents' social support and perceptions of neighborhood cohesion. Participants included 571 urban, African American adolescents (52% female; M age = 17.8). A multilevel path analysis testing both direct and indirect effects of neighborhood characteristics on adolescents' mental health outcomes was conducted. Higher neighborhood poverty and unemployment rates predicted greater internalizing symptoms via lower cumulative social support and perceptions of neighborhood cohesion. In contrast, higher concentrations of African American and residentially stable residents in one's neighborhood related to fewer internalizing symptoms among adolescent residents via greater cumulative social support and perceptions of neighborhood cohesion. Implications of these findings are discussed. 相似文献