全文获取类型
收费全文 | 13367篇 |
免费 | 304篇 |
国内免费 | 375篇 |
专业分类
教育 | 8979篇 |
科学研究 | 2448篇 |
各国文化 | 9篇 |
体育 | 523篇 |
综合类 | 775篇 |
文化理论 | 13篇 |
信息传播 | 1299篇 |
出版年
2024年 | 9篇 |
2023年 | 50篇 |
2022年 | 110篇 |
2021年 | 202篇 |
2020年 | 232篇 |
2019年 | 171篇 |
2018年 | 152篇 |
2017年 | 142篇 |
2016年 | 206篇 |
2015年 | 315篇 |
2014年 | 801篇 |
2013年 | 870篇 |
2012年 | 1055篇 |
2011年 | 1171篇 |
2010年 | 852篇 |
2009年 | 770篇 |
2008年 | 905篇 |
2007年 | 1125篇 |
2006年 | 1141篇 |
2005年 | 946篇 |
2004年 | 802篇 |
2003年 | 676篇 |
2002年 | 516篇 |
2001年 | 419篇 |
2000年 | 214篇 |
1999年 | 77篇 |
1998年 | 34篇 |
1997年 | 29篇 |
1996年 | 18篇 |
1995年 | 5篇 |
1994年 | 4篇 |
1993年 | 8篇 |
1992年 | 4篇 |
1991年 | 4篇 |
1990年 | 7篇 |
1989年 | 2篇 |
1979年 | 1篇 |
1976年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
91.
92.
1958年颁布的《国防教育法》对认识二战后美国的教育变革有重要意义。但长期以来研究者都视其为对"苏联卫星事件"的回应,是冷战时期国防政策的重要内容。笔者通过对文献的重新发掘与分析,指出两者之间不存在必然联系,这场教育改革不是"刺激-反应"模式的产物;此外,该法案立法过程中的焦点问题是对联邦政府干预教育权限的再讨论;法案通过后,在宣誓政治忠诚和学术自由问题上也受到广泛批评。国家安全不能概括法案的全部,至于联邦政府如何干预教育,以法案为代表的每一次讨论本身就是答案。 相似文献
93.
目前,学术界多开展引用动机和引文功能的相关研究,但对于引用偏好等引用行为却关注较少。基于Taylor的信息使用环境理论,本研究采用参考文献分析方法,全面揭示了施引者引用行为的特征和影响因素。研究将信息使用环境理论中的前三类要素分别通过学者特征、组织环境及论题进行定义,采用参考文献分析法提取第四类要素;随机抽取论文样本,针对上述四类特征进行编码并通过统计分析探讨影响施引者引用行为的因素。研究发现:学者的年龄、性别、教育水平、学术年龄、职业角色、职称、所属机构的类型和层次以及所从事的研究主题和类型,都能对质量、语种、数量、信息资源类型、论文新旧的引用偏好产生显著影响。研究表明:信息使用环境理论和参考文献分析法在引用行为研究中具有适用性。表4。参考文献47。 相似文献
94.
大数据时代,信息安全保障能力的提升与制度体系的完善,是世界各国奋力攀登的制高点和国家战略。本文运用文献分析法、比较分析法,对中外信息安全保障概念、立法原则及其法律制度的演化路径进行深入分析。信息安全保障是大安全观下对信息内容安全、数据安全、物理安全、网络安全和信息基础设施安全等的积极防御措施;其法律制度建设正在由分散走向统一,由单纯立法走向“立法与实施机制”并进;其保障体系正在形成一个由技术、管理、法制、文化等多元素、跨国跨区域、全方位的主动积极防御整体联动框架。中国特色的国家安全体制机制,以及“总体安全观”下以《国家安全法》为基准的信息安全法律体系正走向健全与发展之路;新型信息安全保障体系的构建正在成为前沿课题。图2。表5。参考文献105。 相似文献
95.
Jiawei Huang Mahda M. Bagher Heather Dohn Ross Nathan Piekielek Jan Oliver Wallgrün Jiayan Zhao 《Journal of Map & Geography Libraries》2018,14(1):40-63
Libraries have been the key to preserving culture and historic legacy for centuries. One such treasure cataloged in The Pennsylvania State University (Penn State) Libraries is a collection of over 33,000 Sanborn? Fire Insurance Maps. Originally kept safe in metal drawers, the library has embarked on a journey to digitize this abundance of information, combine it with other media such as photographs, and make it accessible through a web interface. Inspired by these efforts, we accessed this information and took it to the next level. Using state of the art 3D modeling and immersive technologies, we created a historic 3D model and immersive experiences of Penn State, exemplarily for the 1922 campus. The resulting experiences can be accessed through the web but also through head mounted displays (HMDs) and mobile phones in combination with VR viewers such as the Google Cardboard. Additionally, they can be used anywhere in the world or on the campus itself as a way to enable remote and in situ experiences and learning. Immersive experiences let us connect to the past, the present and the future, and as such offer value to digital cultural heritage efforts. 相似文献
96.
In this contribution, we develop a new approach to explore the process of knowledge transition from discovery-oriented science to technological fields, via applications-oriented research, including a mediator set. This trajectory is referred to as the D-A-T trajectory. It is shown how it can be constructed and measures are proposed to characterize the relational strength among different environments (discovery oriented research, applications-oriented research and patents) and the speed of evolution. Our approach is illustrated by a case study of three fundamental restriction enzymes articles. Among other results we found that 387 patents cited 124 of the 988 articles (a share of 12.55%) in the mediator set. Defining the non-patent references (NPR) transition rate as the number of citing patents divided by the number of articles in the mediator set yields a value 0.392. Our results suggest that the D-A-T path acts as a backbone and reveals important “invisible contributions” of an original scientific work during its evolution from discovery oriented research to outside academia. Our contribution provides a useful tool for bridging the existing gap in detecting the transition of knowledge between science and technology. 相似文献
97.
Noriaki Hoshino 《Inter-Asia Cultural Studies》2016,17(2):186-205
Focusing on the work of the Japanese sociologist Koyama Eizō, this paper critically explores the development of Japanese race studies from the late 1920s to the 1940s. During this period, Japanese intellectual discourses on race developed in the context of the need to manage heterogeneous populations within the Japanese empire and contain the growing mobility of populations in and outside of the territory. Reflecting Koyama’s keen interest in racial/ethnic contacts and interdisciplinary perspectives, his intellectual work symptomatically exemplifies not only the convergence of knowledge production and the dominant imperial regime but also the transpacific implications of Japanese race studies. On the one hand, my study examines Koyama’s preoccupation with racial/ethnic contacts in relation to imperial security and also traces how his study intersected with the discourse of American social scientists who were also interested in Japanese migrations. On the other hand, the study examines how the development of the idea of minzoku in Koyama’s discourse coincided with contemporaneous attempts to mobilize diverse populations in the empire. Thus, my research reveals a complex dynamic of integration and differentiation in discourse on Japanese race studies in the interwar era. 相似文献
98.
通过对我国2001年至2014年期间,258个户外运动安全事故案例的统计和分析,结合国内外相关研究,建立户外运动安全风险分析框架,将户外运动安全风险划分为4个维度,18个因素指标.根据对应分析模型原理,深入研究户外运动中季节、月份与时段风险的对应性关系,R(3.2.0)软件运行结果显示:户外运动中,凌晨和晚上的风险指数最高;春季、秋季的上午和下午时段,可能存在的伤亡风险几率较高;5月、9月、10月的上午和晚上,3月、6月、11月、12月的下午,1月和4月的凌晨时段,可能存在的伤亡风险几率更高.使用Minitab软件,根据累积贡献率80%以上为主要因素的帕累托原则得到8个主要风险因素和7个次要风险因素. 相似文献
99.
张绍洁 《天津职业院校联合学报》2011,13(11):87-89
信息的安全性在大型企业网络建设和改造提升中,得到的关注日益提高。文章主要介绍了作者本人通过在企业中实习,对信息的安全性方面的一点理解和认识,并对企业中信息管理人员如何结合工作中的需求来实现信息的安全性提出了一些建议。 相似文献
100.
A Framework for Policies and Practices to Improve Test Security Programs: Prevention,Detection, Investigation,and Resolution (PDIR) 下载免费PDF全文
Steve Ferrara 《Educational Measurement》2017,36(3):5-23
Test security is not an end in itself; it is important because we want to be able to make valid interpretations from test scores. In this article, I propose a framework for comprehensive test security systems: prevention, detection, investigation, and resolution. The article discusses threats to test security, roles and responsibilities, rigorous training for everyone involved in testing, and an evaluation of current practices in test security. I call on everyone responsible for testing programs—the Association of Test Publishers, Council of Chief State School Officers, National Council on Measurement in Education, U.S. Department of Education, and state assessment program managers, their vendors, and the research community—to collaborate on guidelines and practices for security violation prevention, detection, investigation, and resolution. 相似文献