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151.
Phonological awareness, phonological memory, and phonological access to lexical storage play important roles in acquiring literacy. We examined the convergent, discriminant, and predictive validity of these phonological processing abilities (PPA) in 389 3-, 4-, and 5-year-old children. Confirmatory factor analysis supported the validity of each PPA as separate from general cognitive ability and separate from each other. Multigroup structural equation modeling (SEM) with mean structure demonstrated that older preschoolers have better developed latent PPA than younger preschoolers but that the structure of PPA is equivalent. RAN was found uniquely associated with letter knowledge and text discrimination in younger preschoolers, and PA was found uniquely associated with word reading skills in older preschoolers. Finally, general cognitive ability was only indirectly associated with emergent literacy via PPA. These results highlight the importance of PPA in the early literacy development of English-speaking preschool children.  相似文献   
152.
Considering the uncertainty of material performance, geometric characteristic and analysis method, the analysis of statistical parameters of the resistance of cast ball-and-socket support joints and the reliability analysis are carried out by JC method (improved first-order second-moment method) based on the relevant experimental data. Results show that the resistance partial factor of the joint increases with the increase of the reliability index. The resistance partial factors are suggested corresponding to the reliability index under different load combinations. Moreover, the suggested resistance partial factor is adopted in reliability design, and it is found that the reliability index of the joint is larger than the target reliability index. The optimal load combination is the one in which live load plays an important control role. Finally, based on the suggested resistance partial factors, the reliability analysis of cast ball-and-socket support joints of a project is conducted.  相似文献   
153.
Funding agencies in Canada are attempting to break down the organizational boundaries between disciplines to promote interdisciplinary research and foster the integration of the social sciences into the health research field. This paper explores the extent to which biomedical and clinician scientists’ perceptions of social science research operate as a cultural boundary to the inclusion of social scientists into this field. Results indicated that cultural boundaries may impede social scientists’ entry into the health research field through three modalities: (1) biomedical and clinician scientists’ unfavourable and ambivalent posture towards social science research; (2) their opposition to a resource increase for the social sciences; and (3) clinician scientists procedural assessment criteria for social science. The paper also discusses the merits and limitations of Tom Gieryn’s concept of boundary-work for studying social dynamics within the field of science.
Brian D. HodgesEmail:
  相似文献   
154.
Tim Ray 《Minerva》2009,47(1):75-92
Half a century after Michael Polanyi conceptualised ‘the tacit component’ in personal knowing, management studies has reinvented ‘tacit knowledge’—albeit in ways that squander the advantages of Polanyi’s insights and ignore his faith in ‘spiritual reality’. While tacit knowing challenged the absurdities of sheer objectivity, expressed in a ‘perfect language’, it fused rational knowing, based on personal experience, with mystical speculation about an un-experienced ‘external reality’. Faith alone saved Polanyi’s model from solipsism. But Ernst von Glasersfeld’s radical constructivism provides scope to rethink personal tacit knowing with regard to ‘other people’ and the intersubjectively viable construction of ‘experiential reality’. By separating tacit knowing from Polanyi’s metaphysical realism and drawing on Benedict Anderson’s concept of ‘imagined communities’, it is possible to conceptualise ‘imagined institutions’ as the tacit dimension of power that shapes human interaction. Whereas Douglass North claimed institutions could be reduced to rules, imagined institutions are known in ways we cannot tell.  相似文献   
155.
This article investigates the effect of a Tony nomination or win on the demand facing a Broadway production using a panel of weekly revenues for Broadway productions from 1996 to 2007. Our results indicate that the effect of a nomination or win is positive in the week of the announcement and gradually increases in successive weeks, presumably due to publicity and word-of-mouth. Winners experience an increase in demand as late as 1 year later when awards are publicized for the following season. Moreover, nominees that do not win the award are penalized heavily in the weeks following the Award announcements. We find that winning a Tony Award increases a production’s revenues by 12% in the week immediately following the Awards.
Lesley ChiouEmail:
  相似文献   
156.
This study considers a frailty duration approach to modelling the life-length of a sample of 360 films that went into wide release at the Australian box office from 1 January 2000 to 31 December 2005. The analysis extends previous research by considering a range of film-specific covariates relating to distribution, production, consumer signals, and weekly performance. In particular, it is shown that film success (defined in a duration context) responds to previewing, advertising, critical reviews, and US box office—but not to production budget, star power or opening-week screens. The study also reveals that it is appropriate to account for unobservable heterogeneity between films in the choice of empirical methodology.  相似文献   
157.
Nathaniel Logar 《Minerva》2009,47(4):345-366
How does the research performed by a government mission agency contribute to useable technologies for its constituents? Is it possible to incorporate science policy mechanisms for increasing benefits to users in the decision process? The United States National Institute of Standards &; Technology (NIST) promises research directed towards industrial application. This paper considers the processes that produce science and technology at NIST. The institute’s policies for science provide robust examples for how effective science policies can contribute to the emergence of useful technologies. To progress towards technologies that can be years away, the agency uses several means for integrating the needs of eventual information users into the prioritization process. To accomplish this, NIST units, such as the Materials Science and Engineering Laboratory, incorporate mechanisms for considering user need and project impact into different stages of its scientific decision processes. This, and other specific strategies that the agency utilizes for connecting the supply of science to information demand, provide lessons for generating useable science.  相似文献   
158.
The present study dealt with the characterisation of marble surfaces coated by three kinds of polymeric material usually employed in stones conservation and with the evaluation of the removal of these coatings from the surfaces by means of new nanocontainer aqueous systems constituted of micellar solutions (MS) and oil-in-water microemulsions (MC). The polymeric coatings were also subjected to accelerated artificial ageing in order to detect possible effects associated to natural photochemical ageing. The aim of the work was the assessment of the performance of such nanocontainer aqueous systems taking acetone (Ac) as a reference “traditional” solvent for the removal procedure. The characterisation was carried out by means of Scanning Electron Microscopy (SEM) and Environmental Scanning Electron Microscopy (ESEM), Fourier Transform Infra-Red (FTIR) and Nuclear Magnetic Resonance (NMR) spectroscopies and the results obtained showed that the performance of these innovative methods based on nanocontainer aqueous systems can be considered highly promising in the view of a “green approach” to the conservation of cultural heritage.  相似文献   
159.
Probability density function (PDF) method is proposed for analysing the structure of the reconstructed attractor in computing the correlation dimensions of RR intervals of ten normal old men. PDF contains important information about the spatial distribution of the phase points in the reconstructed attractor. To the best of our knowledge, it is the first time that the PDF method is put forward for the analysis of the reconstructed attractor structure. Numerical simulations demonstrate that the cardiac systems of healthy old men are about 6 - 6.5 dimensional complex dynamical systems. It is found that PDF is not symmetrically distributed when time delay is small, while PDF satisfies Gaussian distribution when time delay is big enough. A cluster effect mechanism is presented to explain this phenomenon. By studying the shape of PDFs, that the roles played by time delay are more important than embedding dimension in the reconstruction is clearly indicated. Results have demonstrated that the PDF method represents a promising numerical approach for the observation of the reconstructed attractor structure and may provide more information and new diagnostic potential of the analyzed cardiac system.  相似文献   
160.
Increased awareness of the problem of child sexual abuse has resulted in increasing numbers of children presenting to professionals for the evaluation of possible sexual victimization. A multidisciplinary project to develop professionals' knowledge and skills in the identification and evaluation of possible victims is described. The program focused on the child as a victim and emphasized developmental perspectives with regard to identification, interviewing children, the medical examination, and children in the legal system. Fifty-one medical and social work professionals from ten Indiana counties attended the program and responded to questionnaires about their experience and knowledge. Of 40 (78%) respondents, 63% had had no previous training in the medical evaluation for child sexual abuse. Child protective workers referred alleged victims primarily to the child's regular physician (37%) or emergency room (31%) for medical examination. Knowledge about child sexual abuse improved significantly at two weeks postsymposium (p = .001) and remained improved at six months postsymposium (p less than .02). These original participants have subsequently organized similar multidisciplinary programs in their local communities for medical, social, law enforcement, and legal professionals; thus, they have been "seeds" for further educational and cooperative efforts throughout the state.  相似文献   
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