全文获取类型
收费全文 | 21892篇 |
免费 | 127篇 |
国内免费 | 20篇 |
专业分类
教育 | 16028篇 |
科学研究 | 2283篇 |
各国文化 | 105篇 |
体育 | 1403篇 |
综合类 | 6篇 |
文化理论 | 486篇 |
信息传播 | 1728篇 |
出版年
2021年 | 83篇 |
2020年 | 136篇 |
2019年 | 202篇 |
2018年 | 2403篇 |
2017年 | 2308篇 |
2016年 | 1788篇 |
2015年 | 279篇 |
2014年 | 356篇 |
2013年 | 2157篇 |
2012年 | 439篇 |
2011年 | 896篇 |
2010年 | 1004篇 |
2009年 | 595篇 |
2008年 | 826篇 |
2007年 | 1335篇 |
2006年 | 248篇 |
2005年 | 567篇 |
2004年 | 598篇 |
2003年 | 541篇 |
2002年 | 294篇 |
2001年 | 186篇 |
2000年 | 188篇 |
1999年 | 176篇 |
1998年 | 88篇 |
1997年 | 103篇 |
1996年 | 125篇 |
1995年 | 90篇 |
1994年 | 109篇 |
1993年 | 110篇 |
1992年 | 174篇 |
1991年 | 172篇 |
1990年 | 151篇 |
1989年 | 145篇 |
1988年 | 129篇 |
1987年 | 130篇 |
1986年 | 157篇 |
1985年 | 148篇 |
1984年 | 118篇 |
1983年 | 141篇 |
1982年 | 128篇 |
1981年 | 114篇 |
1980年 | 105篇 |
1979年 | 177篇 |
1978年 | 117篇 |
1977年 | 117篇 |
1976年 | 111篇 |
1975年 | 88篇 |
1974年 | 98篇 |
1972年 | 72篇 |
1971年 | 75篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
81.
Der gleichzeitige Betrieb mehrerer Gast-Betriebssysteme auf einem einzigen physischen Rechner unter einem Host-Betriebssystem ist eine leistungsfähige moderne Entwicklung. Bekannte Beispiele sind VMware für die IA32-Architektur sowie das Betriebssystem z/VM und die PR/SM-LPAR Einrichtungen der zSeries-Architektur. Die Nutzung eines Betriebssystems als Gast bedingt einen Leistungsverlust. Die als Partitionierung bezeichnete Zuordnung von Systemressourcen zu den einzelnen Gast-Betriebssysteme ist schwierig, wenn eine dynamische Anpassung an sich ändernde Lastprofile erforderlich ist. Diese Probleme lassen sich mittels Erweiterungen der Hardwarearchitektur adressieren, sowie durch Softwarestrukturen, welche diese Erweiterungen nutzen. Die Erweiterungen der Hardwarearchitektur gehen über das hinaus, was auf heutigen Rechnerarchitekturen wie IA32 oder Mips verfügbar ist. Der vorliegende Beitrag erläutert den optimalen Betrieb von Gast-Betriebssystemen und die begleitenden Partitionierungsmöglichkeiten auf der zSeries-Plattform und beschreibt die zusätzlichen Hardware- und Software-Einrichtungen, welche dies ermöglichen. 相似文献
82.
83.
传媒经济学研究的历史、方法与范例 总被引:3,自引:0,他引:3
本文主要回顾了传媒经济学在西方的发展历程、研究方法以及不同时期的研究议题。传媒经济学是构建于不同的经济学理论和分析方法之上的应用性学科,它致力于研究经济和金融力量如何影响传媒体系和传媒组织。西方传媒经济学创建于20世纪50年代,至今已发展成为一个活跃的和跨学科研究领域。文章认为,西方传媒经济学的主要研究范例包括理论型、应用型和批评型范例;其研究方法可分为行业市场研究、公司研究和影响力研究。在介绍西方传媒经济学研究的同时,本文还简要回顾了传媒经济学在中国的兴起与发展。 相似文献
84.
85.
Question classification systems play an important role in question answering systems and can be used in a wide range of other domains. The goal of question classification is to accurately assign labels to questions based on expected answer type. Most approaches in the past have relied on matching questions against hand-crafted rules. However, rules require laborious effort to create and often suffer from being too specific. Statistical question classification methods overcome these issues by employing machine learning techniques. We empirically show that a statistical approach is robust and achieves good performance on three diverse data sets with little or no hand tuning. Furthermore, we examine the role different syntactic and semantic features have on performance. We find that semantic features tend to increase performance more than purely syntactic features. Finally, we analyze common causes of misclassification error and provide insight into ways they may be overcome. 相似文献
86.
ABSTRACTLighting a cultural heritage artifact requires balancing visual perception with preventive conservation, by providing the best lighting (in terms of spectral distribution and quantity) to enable the viewer to appreciate details and color, while limiting photo-induced degradation. The paper outlines the methodology applied by a multi-disciplinary team while lighting the Shroud of Turin at its last public exhibition in 2015. The methodology considered the special requirements of the Shroud, including exposure to ultraviolet light, while providing appropriate display conditions that would meet audience expectations. The desired appearance (readability of the body image and color) was defined with the help of Shroud researchers and confirmed by subjective tests, while appropriate light levels for preservation were set in agreement with standard requirements and using knowledge of the degradation of linen in visible and UV light. The installation provided a controlled environment and a managed visitor route to the Shroud, assuring excellent perception of both details and color, with the lowest illuminance level about 15?lx. 相似文献
87.
Walter Moreira 《Cataloging & classification quarterly》2018,56(1):19-39
Knowledge organization systems have been studied in several fields and for different and complementary aspects. Among the aspects that concentrate common interests, in this article we highlight those related to the terminological and conceptual relationships among the components of any knowledge organization system. This research aims to contribute to the critical analysis of knowledge organization systems, especially ontologies, thesauri, and classification systems, by the comprehension of its similarities and differences when dealing with concepts and their ways of relating to each other as well as to the conceptual design that is adopted. 相似文献
88.
Nathan Walter Sheila T. Murphy Erica L. Rosenthal 《Communication Research Reports》2018,35(5):402-412
The study explored the role of second-screen use and binge-watching in moderating entertainment education (EE) effects. A pretest/posttest experiment of 273 viewers of East Los High measured the effects of exposure to three subplots, concerning alcohol abuse, abortion, and immigration. The effect of identification with characters on change in attitudes was significantly moderated by second-screen use and binge-watching. In particular, second-screening tended to enhance the positive impact of identification; whereas, among respondents who binge-watched the show, the effects of identification were weaker. 相似文献
89.
There are three models for community archives in China. The first one is where community archives are kept in government-funded/government-established museums or archives. The second is where community archives are kept by scholarly organizations such as universities. The third involves the community establishing its own archive. This last model is very unusual in China. The PiCun Culture and Art Museum of Migrant Labor (PCMML) provides an example of this model as it is the only independent community archives focusing on migrant workers in China. This paper explores the emergence and development of PCMML, its impact on community members and challenges faced including funding and staffing, but also those unique to China—PCMML is greatly influenced by a range of national and local government policies and regulations. Conclusions are that survival strategies for independent community archives in China are dependent on three dimensions: the community itself, society and the government. Cultural consciousness of the community is the premise for the establishment and sustainability of independent community archives, and independent community archives can be the public space to cultivate cultural consciousness of community members and thus activates community members’ agency to document, preserve and disseminate their own history. At the same time, independent community archives also need to engage with broader society to avoid involution and gain support and understanding. Independent community archives are constrained by government policies and regulations, so it is essential for them to develop strategic relationships with government. 相似文献
90.
Textbook vetting and evaluation process intends to ensure that the materials provided are relevant, of the required quality, suitable ad would enhance learning efficiency and effectiveness. The paper investigates the role of publishers and Tanzania Institute of Education (TIE) in the textbooks vetting and evaluation process; examines factors used to vet, evaluate and approve primary and secondary school textbooks in Tanzania and proposes Strategies that would enhance the textbook vetting, evaluation and process. The study used a mixed method research design. Respondents were selected educational publishers; MoEVT, Baraza la Kiswahili Tanzania, TIE, and Publishers Association of Tanzania. Questionnaire and semi- structured interview were used to collect data which were analysed qualitatively and quantitatively. Major findings of the study were; textbooks vetting and evaluation process is not professionally conducted although standard criteria have been established; there is not well established roles among key players involved in the vetting and evaluation process leading to conflict of interest between TIE and the publishers. The study recommends establishing an independent professional evaluation board and a well-defined timetable and effective communication among various players; enacting a book policy and adopting a limited multiple-textbook publishing system. 相似文献