全文获取类型
收费全文 | 2369篇 |
免费 | 39篇 |
国内免费 | 209篇 |
专业分类
教育 | 1014篇 |
科学研究 | 887篇 |
各国文化 | 4篇 |
体育 | 62篇 |
综合类 | 43篇 |
文化理论 | 10篇 |
信息传播 | 597篇 |
出版年
2024年 | 2篇 |
2023年 | 24篇 |
2022年 | 53篇 |
2021年 | 93篇 |
2020年 | 120篇 |
2019年 | 76篇 |
2018年 | 74篇 |
2017年 | 72篇 |
2016年 | 47篇 |
2015年 | 87篇 |
2014年 | 170篇 |
2013年 | 173篇 |
2012年 | 134篇 |
2011年 | 164篇 |
2010年 | 135篇 |
2009年 | 191篇 |
2008年 | 160篇 |
2007年 | 176篇 |
2006年 | 120篇 |
2005年 | 141篇 |
2004年 | 128篇 |
2003年 | 95篇 |
2002年 | 66篇 |
2001年 | 41篇 |
2000年 | 25篇 |
1999年 | 15篇 |
1998年 | 8篇 |
1997年 | 5篇 |
1996年 | 3篇 |
1995年 | 3篇 |
1994年 | 2篇 |
1993年 | 2篇 |
1992年 | 2篇 |
1989年 | 2篇 |
1988年 | 1篇 |
1987年 | 2篇 |
1986年 | 2篇 |
1985年 | 2篇 |
1984年 | 1篇 |
排序方式: 共有2617条查询结果,搜索用时 15 毫秒
151.
提出了一种基于数据挖掘技术的Web智能服务算法,它通过对Web数据模型的转换,发现并建立有关用户意向关联知识库,然后再利用知识库中的关联规则来预测用户行为,从而提高了用户浏览器访问速度。该研究内容属目前智能信息检索领域的重要研究课题,具有一定的理论和实践意义。 相似文献
152.
余晓征 《广州广播电视大学学报》2006,6(1):23-26
鉴于当前基于主机入侵检测系统的局限性,使得基于代理的入侵检测技术显得日益重要。讨论从基于主机的入侵检测系统的局限性出发,提出了一种基于多代理机制的分布式入侵检测系统方案,并对入侵检测系统中主机检测器基于多代理的技术进行了详细分析和难点解析。 相似文献
153.
Unicorn系统中简编记录升级为详编记录的新方法研究 总被引:1,自引:0,他引:1
概括介绍了在Unicorn 系统中如何使详编记录在装载时成批替换数据库中的简编记录, 以及这种方法的可行性、应用情况和提高替换率的方法。 相似文献
154.
155.
Jeffrey K. Uhlmann 《Journal of The Franklin Institute》2004,341(7):569-593
This paper examines some of the combinatorial issues associated with the batch data association problem arising in tracking and correlation applications. A procedure is developed that addresses a large class of data association problems involving the calculation of permanents of submatrices of the original association matrix. This procedure yields what is termed the Joint Assignment Matrix (JAM), which can be used to optimally rank associations for hypothesis selection. Because the computational cost of the permanent scales exponentially with the size of the matrix, improved algorithms are developed both for calculating the exact JAM and for generating approximations to it. Empirical results suggest that at least one of the approximations is suitable for real-time hypothesis generation in large scale tracking and correlation applications. Novel theoretical results include an improved upper bound on the calculation of the JAM and new upper bound inequalities for the permanent of general nonnegative matrices. One of these inequalities is an improvement over the best previously known inequality. 相似文献
156.
Hong-Guang Ma Xiao-Fei Zhu Ming-Shun Ai Ji-Dong Wang 《Journal of The Franklin Institute》2007,344(8):1102-1112
A fault diagnosis method for analog circuit is proposed in this paper. An all-purpose amplifier is taken as the typical circuit under test (CUT). The chaotic signal, which is generated by an improved Chua's circuit, is employed as the excitation signal of CUT. The algorithm for phase-space reconstruction of chaotic time series is a combination algorithm of multiple autocorrelation and Γ-test. The circuit state is estimated based on detecting the geometric change of Chua's attractor with a data-mining approach. For the purpose of information fusion, another eight features are extracted from the testing data to comprehensively determine the CUT states. A discussion is made for comparing the effectiveness of each feature according to the testing results. 相似文献
157.
Current citation-based document retrieval systems generally offer only limited search facilities, such as author search. In order to facilitate more advanced search functions, we have developed a significantly improved system that employs two novel techniques: Context-based Cluster Analysis (CCA) and Context-based Ontology Generation frAmework (COGA). CCA aims to extract relevant information from clusters originally obtained from disparate clustering methods by building relationships between them. The built relationships are then represented as formal context using the Formal Concept Analysis (FCA) technique. COGA aims to generate ontology from clusters relationship built by CCA. By combining these two techniques, we are able to perform ontology learning from a citation database using clustering results. We have implemented the improved system and have demonstrated its use for finding research domain expertise. We have also conducted performance evaluation on the system and the results are encouraging. 相似文献
158.
The purpose of this study was to assess the sources of award-wining research professors’ (six women; six men) teaching self-efficacy through the framework of Bandura’s (1986) social cognitive theory. Semi-structured interviews revealed that mastery experiences and social persuasions were particularly influential sources of self-efficacy and that these sources tended to be closely related. Professors reported that their self-efficacy had generally stabilized within their first few years of assuming a tenure-track position. Participants framed negative events in adaptive ways that had little cost to their teaching self-efficacy. 相似文献
159.
160.
季士妍 《现代图书情报技术》2011,(3):94-97
以国家图书馆二版主题词升级为背景,介绍升级中书目数据更新的整体情况,分析书目数据替换产生的依据及规则,并针对每种书目数据替换进行程序实现说明。 相似文献