首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   2707篇
  免费   47篇
  国内免费   3篇
教育   2109篇
科学研究   187篇
各国文化   35篇
体育   183篇
综合类   4篇
文化理论   30篇
信息传播   209篇
  2023年   14篇
  2022年   31篇
  2021年   48篇
  2020年   68篇
  2019年   90篇
  2018年   127篇
  2017年   131篇
  2016年   129篇
  2015年   79篇
  2014年   94篇
  2013年   568篇
  2012年   105篇
  2011年   89篇
  2010年   67篇
  2009年   60篇
  2008年   81篇
  2007年   69篇
  2006年   67篇
  2005年   70篇
  2004年   71篇
  2003年   48篇
  2002年   55篇
  2001年   43篇
  2000年   47篇
  1999年   39篇
  1998年   29篇
  1997年   19篇
  1996年   19篇
  1995年   20篇
  1994年   22篇
  1993年   21篇
  1992年   11篇
  1991年   26篇
  1990年   24篇
  1989年   24篇
  1988年   15篇
  1987年   22篇
  1986年   11篇
  1985年   28篇
  1984年   18篇
  1983年   8篇
  1982年   12篇
  1981年   10篇
  1980年   7篇
  1979年   10篇
  1978年   7篇
  1977年   10篇
  1976年   14篇
  1974年   7篇
  1880年   5篇
排序方式: 共有2757条查询结果,搜索用时 31 毫秒
151.
High-fidelity anatomical models can be produced with three-dimensional (3D) scanning techniques and as such be digitally preserved, archived, and subsequently rendered through various media. Here, a novel methodology—digital body preservation—is presented for combining and matching scan geometry with radiographic imaging. The technique encompasses joining layers of 3D surface scans in an anatomical correct spatial relationship. To do so, a computed tomography (CT) volume is used as template to join and merge different surface scan geometries by means of nonrigid registration into a single environment. In addition, the use and applicability of the generated 3D models in digital learning modalities is presented. Finally, as computational expense is usually the main bottleneck in extended 3D applications, the influence of mesh simplification in combination with texture mapping on the quality of 3D models was investigated. The physical fidelity of the simplified meshes was evaluated in relation to their resolution and with respect to key anatomical features. Large- and medium-scale features were well preserved despite extensive 3D mesh simplification. Subtle fine-scale features, particular in curved areas demonstrated the major limitation to extensive mesh size reduction. Depending on the local topography, workable mesh sizes ranging from 10% to 3% of the original size could be obtained, making them usable in various learning applications and environments.  相似文献   
152.
To learn language, children must map variable input to categories such as phones and words. How do children process variation and distinguish between variable pronunciations (“shoup” for soup) versus new words? The unique sensory experience of children with cochlear implants, who learn speech through their device's degraded signal, lends new insight into this question. In a mispronunciation sensitivity eyetracking task, children with implants (N = 33), and typical hearing (N = 24; 36–66 months; 36F, 19M; all non-Hispanic white), with larger vocabularies processed known words faster. But children with implants were less sensitive to mispronunciations than typical hearing controls. Thus, children of all hearing experiences use lexical knowledge to process familiar words but require detailed speech representations to process variable speech in real time.  相似文献   
153.
We digitized three years of Dutch election manifestos annotated by the Dutch political scientist Isaac Lipschits. We used these data to train a classifier that can automatically label new, unseen election manifestos with themes. Having the manifestos in a uniform XML format with all paragraphs annotated with their themes has advantages for both electronic publishing of the data and diachronic comparative data analysis. The data that we created will be disclosed to the public through a search interface. This means that it will be possible to query the data and filter them on themes and parties. We optimized the Lipschits classifier on the task of classifying election manifestos using models trained on earlier years. We built a classifier that is suited for classifying election manifestos from 2002 onwards using the data from the 1980s and 1990s. We evaluated the results by having a domain expert manually assess a sample of the classified data. We found that our automatic classifier obtains the same precision as a human classifier on unseen data. Its recall could be improved by extending the set of themes with newly emerged themes. Thus when using old political texts to classify new texts, work is needed to link and expand the set of themes to newer topics.  相似文献   
154.
Combining both interview data and empirical analyses at the patent and firm levels, we explore the value-appropriation and value-creation implications of R&D collaboration resulting in the co-ownership of intellectual property (i.e. co-patents). We make an explicit distinction between three different types of co-patenting partners: intra-industry partners, inter-industry partners, and universities. Our findings indicate that the value-appropriation challenges of IP sharing are clearly evident with intra-industry co-patenting, where partners are more likely to encounter overlapping exploitation domains. Co-patenting with universities is associated with higher market value, since appropriation challenges are unlikely to play a role and collaboration may signal novel technological opportunities. Although we find some evidence that co-patenting corresponds to higher (patent) value, patents co-owned with firms are significantly less likely to receive self-citations, indicating constraints on the future exploitation and development of co-owned technologies.  相似文献   
155.
156.
157.
158.
The impact of electric overhead radiant heaters on the microclimate, air flows, transport and deposition of suspended particulate matter (SPM) was monitored between March 2004 and March 2005 in the historic churches of Saint Michael Archangel in Szalowa and Saint Catherine in Cracow (Poland). The measurements show that although irradiation at the floor level increases temperature and reduces relative humidity in the interior of the church, the effect out of the heated zone and for the surfaces sheltered from irradiation is very limited, i.e. their extent is comparable with natural fluctuations inherent to the local climate of the church. The radiant heaters proved to generate little convectional flow of the air. Therefore, the heating system was not found to increase the concentration of SPM indoors; in particular, no re-suspension of particles already present in the church was observed. This work has demonstrated that the overhead radiant heaters are capable of providing localised heat to the areas where people congregate without adversely affecting painted walls and the works of arts displayed in churches. Care, however, should be taken that sensitive works of art are not exposed to the direct infrared radiation.  相似文献   
159.
160.
This paper starts from a brief sketch of the ‘classical’ figure of critical educational theory or science (Kritische Erziehungswissenshaft). ‘Critical educational theory’ presents itself as the privileged guardian of the critical principle of education (Bildung) and its emancipatory promise. It involves the possibility of saying ‘I’ in order to speak and think in one's own name, to be critical, self‐reflective and independent, to determine dependence from the present power relations and existing social order. Actual social and educational reality and relations are approached as a limitation, threat, alienation, re/oppression or negation of ultimate human principles or potential. The task of critical educational theory becomes one of enabling an autonomous, critical, self‐reflective life. While ‘critique’ and ‘autonomy’ have meanwhile become commonplace, and ‘critique’ and ‘autonomy’ are reclaimed and required from everybody, we should also consider the question of the relation between an institutional or ideological framework as that which claims to question this frame and to constitute its opposite. The trivialisation of critique is taken as occasion to recall Michel Foucault's analysis of power relations and especially his thesis according to which the ‘government of individualisation’ is the actual figure of power. Starting from the framework offered by Foucault, it can be made clear that the autonomous, critical, self‐reflective life does not represent an ultimate principle but refers to a very specific form of subjectification operating as a transmission belt for power. The autonomous, critical, self‐reflective person appears as an historical model of self‐conduct whereby power operates precisely through the intensification of reflectiveness and critique rather than through their repression, alienation or negation. This brings us back then to the question of how to conceive of the task of a critical educational theory at a time in which critique, autonomy and self‐determination have become an essential modus operandi of the existing order.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号