全文获取类型
收费全文 | 13373篇 |
免费 | 425篇 |
国内免费 | 500篇 |
专业分类
教育 | 9300篇 |
科学研究 | 2255篇 |
各国文化 | 110篇 |
体育 | 520篇 |
综合类 | 838篇 |
文化理论 | 21篇 |
信息传播 | 1254篇 |
出版年
2024年 | 8篇 |
2023年 | 99篇 |
2022年 | 161篇 |
2021年 | 299篇 |
2020年 | 425篇 |
2019年 | 350篇 |
2018年 | 293篇 |
2017年 | 283篇 |
2016年 | 356篇 |
2015年 | 400篇 |
2014年 | 439篇 |
2013年 | 863篇 |
2012年 | 993篇 |
2011年 | 981篇 |
2010年 | 531篇 |
2009年 | 659篇 |
2008年 | 922篇 |
2007年 | 1066篇 |
2006年 | 1153篇 |
2005年 | 967篇 |
2004年 | 814篇 |
2003年 | 611篇 |
2002年 | 460篇 |
2001年 | 311篇 |
2000年 | 257篇 |
1999年 | 132篇 |
1998年 | 86篇 |
1997年 | 81篇 |
1996年 | 72篇 |
1995年 | 40篇 |
1994年 | 40篇 |
1993年 | 37篇 |
1992年 | 30篇 |
1991年 | 21篇 |
1990年 | 15篇 |
1989年 | 21篇 |
1988年 | 3篇 |
1987年 | 6篇 |
1985年 | 5篇 |
1984年 | 2篇 |
1983年 | 2篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1976年 | 1篇 |
1957年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
62.
GPS/GIS车辆监控管理系统中的关键技术 总被引:1,自引:0,他引:1
简要论述了车辆监控管理系统的工作原理及通信链路的选择策略,针对一套实用的GPS/GIS车辆监控系统设计方案,详细阐述了系统设计中的关键技术. 相似文献
63.
跨国公司技术转移研究评述 总被引:10,自引:0,他引:10
跨国公司是影响世界经济发展和技术进步的重要力量。本文通过对1960年代以来国内外学术界有关跨国公司技术转移影响东道国或地区经济增长和技术进步的理论和实证研究成果进行细致的分析和梳理发现:整体上看,跨国公司的直接投资对东道国或地区经济增长和技术进步的影响是不确定的。在很多情况下,跨国公司的技术控制会造成东道国或地区企业长期的技术依赖。更重要的是,学术界一直缺乏基于提高东道国或地区技术创新能力视角的研究,更缺乏精确度量技术转移程度的指标体系,而这正是我们全面、客观、科学评价跨国公司技术转移和技术扩散的出发点。 相似文献
64.
趋势与前景:新世纪师范教育发展探寻 总被引:8,自引:0,他引:8
新世纪的中国师范教育将在以下方面出现新发展、新变化 :减少办学层次、开放培养体系、完善课程结构、促进一体化教育、提高专业化水平、掌握信息技术、加强高师教师队伍建设 相似文献
65.
This paper addresses a dynamic portfolio investment problem. It discusses how we can dynamically choose candidate assets, achieve the possible maximum revenue and reduce the risk to the minimum level. The paper generalizes Markowitz's portfolio selection theory and Sharpe's rule for investment decision. An analytical solution is presented to show how an institutional or individual investor can combine Markowitz's portfolio selection theory, generalized Sharpe's rule and Value-at-Risk(VaR) to find candidate assets and optimal level of position sizes for investment (dis-investment). The result shows that the generalized Markowitz's portfolio selection theory and generalized Sharpe's rule improve decision making for investment. 相似文献
66.
67.
The performance of speaker verification systems is often compromised under real-world environments. For example, variations in handset characteristics could cause severe performance degradation. This paper presents a novel method to overcome this problem by using a non-linear handset mapper. Under this method, a mapper is constructed by training an elliptical basis function network using distorted speech features as inputs and the corresponding clean features as the desired outputs. During feature recuperation, clean features are recovered by feeding the distorted features to the feature mapper. The recovered features are then presented to a speaker model as if they were derived from clean speech. Experimental evaluations based on 258 speakers of the TIMIT and NTIMIT corpuses suggest that the feature mappers improve the verification performance remarkably. 相似文献
68.
陈英杰 《三门峡职业技术学院学报》2007,6(3):1-4
本文从世界高等教育发展史、我国高等职业教育发展史和我国学位制度的演变说明高等职业教育是一种类型,并对今后我国职业教育的发展从认识上、制度上、具体办学上相应提出了建议。 相似文献
69.
Limeng Liang 《International Journal of Disability, Development & Education》2016,63(3):369-383
This article reports on a mixed-method inquiry into pre-service and in-service secondary school teachers’ knowledge about Attention-deficit Hyperactivity Disorder (ADHD) and attitudes toward students with this disorder in Hong Kong. The inquiry revealed no differences between pre-service and in-service secondary school teachers concerning their knowledge of ADHD and attitudes toward students with ADHD. It also identified possible sources of participants’ knowledge and a variety of factors underlying their attitudes toward students with ADHD including sociocultural beliefs and working conditions. The findings call for teacher educators to develop better education programmes to support both pre-service and in-service teachers in undertaking the challenging task of teaching students with ADHD. 相似文献
70.
Robert W. Bell 《PRIMUS》2017,27(3):406-417
AbstractMentoring undergraduate students in research is both rewarding and challenging. In this paper we present how we established a summer Research Experience for Undergraduates (REU) program in the mathematical sciences at Michigan State University. A goal of our REU is to include students who are at an early stage of their study of mathematics. We share our experiences in recruiting students, designing research projects, and mentoring our participants. We discuss the challenges we faced and the solutions we found while working with a diverse group of undergraduate students from across the nation. 相似文献