全文获取类型
收费全文 | 33562篇 |
免费 | 348篇 |
国内免费 | 30篇 |
专业分类
教育 | 24751篇 |
科学研究 | 3130篇 |
各国文化 | 206篇 |
体育 | 2024篇 |
综合类 | 34篇 |
文化理论 | 560篇 |
信息传播 | 3235篇 |
出版年
2022年 | 133篇 |
2021年 | 229篇 |
2020年 | 363篇 |
2019年 | 493篇 |
2018年 | 2734篇 |
2017年 | 2721篇 |
2016年 | 2191篇 |
2015年 | 535篇 |
2014年 | 686篇 |
2013年 | 4352篇 |
2012年 | 763篇 |
2011年 | 1295篇 |
2010年 | 1271篇 |
2009年 | 870篇 |
2008年 | 1129篇 |
2007年 | 1588篇 |
2006年 | 510篇 |
2005年 | 763篇 |
2004年 | 792篇 |
2003年 | 674篇 |
2002年 | 506篇 |
2001年 | 432篇 |
2000年 | 418篇 |
1999年 | 403篇 |
1998年 | 212篇 |
1997年 | 248篇 |
1996年 | 256篇 |
1995年 | 220篇 |
1994年 | 212篇 |
1993年 | 199篇 |
1992年 | 306篇 |
1991年 | 306篇 |
1990年 | 332篇 |
1989年 | 314篇 |
1988年 | 302篇 |
1987年 | 251篇 |
1986年 | 262篇 |
1985年 | 326篇 |
1984年 | 268篇 |
1983年 | 258篇 |
1982年 | 199篇 |
1981年 | 209篇 |
1980年 | 176篇 |
1979年 | 242篇 |
1978年 | 216篇 |
1977年 | 197篇 |
1976年 | 161篇 |
1975年 | 130篇 |
1974年 | 120篇 |
1973年 | 147篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
941.
In this paper, we consider theories about processes of visual perception and perception-based knowledge representation (VPR)
in order to explain difficulties encountered in figural processing in junior high school geometry tasks. In order to analyze
such difficulties, we take advantage of the following perspectives of VPR: (1) Perceptual organization: Gestalt principles,
(2) recognition: bottom-up and top-down processing; and (3) representation of perception-based knowledge: verbal vs. pictorial
representation, mental images and hierarchical structure of images. Examples given in the paper were mostly taken from Gal's
study (2005) which aimed at identifying and analyzing Problematic Learning Situations (after Gal & Linchevski, 2000) in junior high school geometry classes. Gal's study (2005) suggests that while this theoretical perspective became part of teachers' pedagogic content knowledge, the teachers were
aware of their students' thinking processes and their ability to analyze and cope with their students’ difficulties in geometry
was improved. 相似文献
942.
Amy B. Adcock Molly H. Duggan Ginger S. Watson Lee A. Belfore 《British journal of educational technology : journal of the Council for Educational Technology》2010,41(3):388-402
This paper describes an assessment of a web‐based interview simulation designed to teach empathetic helping skills. The system includes an animated character acting as a client and responses designed to recreate a simulated role‐play, a common assessment method used for teaching these skills. The purpose of this study was to determine whether learning gains found in previous evaluations would transfer to students needing similar skill sets but in different areas of study. Findings indicate a positive trend in learning gains across both areas of study (human services and counselling) with no significant differences in skill acquisition. Developers of the system conclude that the system is effective in the general training of empathetic helping skills regardless of the students' area of study. 相似文献
943.
944.
Depending on the kindness of strangers: current national data initiatives and developmental research 总被引:2,自引:0,他引:2
This article provides a brief review of current large-scale, longitudinal data collection initiatives focusing on children. These studies will be available for secondary data analyses in the twenty-first century. In addition to child outcome data, process-oriented information is being collected on child-parent interactions, quality of child care, elementary school teacher reports and classroom observations, accessibility and use of health, educational and social services, parental mental health, family violence, fathering, parental residence patterns, income and income sources, child support, employment patterns, and community characteristics. Several of these studies are randomized trials of the efficacy of early childhood intervention services and housing mobility programs. The usefulness of these efforts for exploring policy-relevant issues (child support enforcement, work requirements for welfare recipients, antipoverty strategies, housing subsidies and relocation, availability of child care, child-care subsidies) are discussed. 相似文献
945.
ZHANG Ji-gao 《浙江大学学报(A卷英文版)》2007,8(3):361-369
Particle pollution in air, also sometimes known as fine dust contamination, may cause electric contact failure. Recent research further proved that the fine particle is becoming a major disruption of the electronic connectors in signal transmission system. This paper specifies the connector contact in mobile phone application. To study the contact failure of mobile phone, a series of inspections and analytical research methods are introduced. Special features that cause the contact failure are summarized. Particle accumulation is the main problem; organic material such as lactates from sweat of the human body may act as adhesives to stick the separate particles together and make them adhere on the contact surface; chemical properties of dust cause serious local corrosion. The corrosion products may trap the particles and firmly attach on the contact surface; micro motion frequently occurs at the contact interface. Hard particle can be embedded into the surface, and soft particle could be squeezed and inserted into the contact; silicon compounds in dust play the most important role in forming high resistance regions that lead to failure; deposition of particles depends on the amount of materials, static electricity attracting force and gravity force applied on the particles. Current dust test can hardly reflect the serious contact failure. It is difficult to simulate the complexity of contact failure caused by particle contamination. Thus alternative ways of simulation experiment and improvement of contact reliability are proposed. 相似文献
946.
Thinking aloud together: A teacher’s semiotic mediation of a whole-class conversation about percents
How does classroom interaction support students’ apprenticeship into the ways of speaking, writing, and diagramming that constitute the practice of mathematics? We address this problem through an interpretative analysis of a whole-group conversation about alternative ways of solving a problem involving percent discounts that occurred in a sixth grade classroom. This research study draws upon Dewey’s theory of inquiry, Vygotsky’s cultural–historical psychology, Freudenthal’s realistic mathematics education, and Halliday’s systemic functional linguistics (SFL). From Freudenthal, we borrow the notions of mathematizing and guided reinvention—the former notion offers a view of mathematics as an activity of structuring subject matter and the latter one provides insights into the processes whereby mathematizing is learned and taught in the classroom. We glean from Dewey his view of reflective thinking as inquiry and the role that conversations may serve therein. We rely upon Vygotsky’s notions of a verbal thinking plane and a social phase of learning in order to reconsider the function of whole-class interaction in apprenticing students into mathematizing. Finally, SFL provides us with tools for explaining the choices of grammar and vocabulary students and teachers make as they realize meanings in whole-group conversations. Treating the selected whole-class conversation as a text, we focus our analysis on how this text came to mean what it did. Our central questions are as follows: What meanings were realized in the whole-class conversation by teacher and students and how were these meanings realized? How did the teacher’s lexico-grammatical choices guide the students’ choices? In addressing these questions, we advance an interpretation of the conversation as paradigmatic of students and teacher thinking aloud together about percents. 相似文献
947.
948.
949.
Lawrence R. Wheeless Ann Bainbridge Frymier Catherine A. Thompson 《Communication quarterly》2013,61(2):102-115
This study tested relationships among verbal output, behavioral receptivity, attraction, and communication satisfaction in a variety of longer and shorter term relationships of differing levels of liking. Two behaviorally referenced reports on others were developed to measure perceived behavioral output and perceived behavioral receptivity. The study tested hypotheses within the attraction paradigm. Results generally supported the notion of an important reinforcement value of high behavioral receptivity and moderate verbal output. Substantial proportions of highly verbal people appeared to be below average in receptivity. 相似文献
950.
A novel floating foundation to support the NREL offshore 5 MW wind turbine was designed conceptually by combining the characteristics of barge and Spar. The main focus was structural design and hydrodynamic modelling. Based on this novel floating foundation, the hydrodynamic performance was investigated in the frequency domain and time domain by using the wave analysis software HydroD and DeepC from Det Norske Veritas. The frequency domain analysis was conducted to investigate the effects of the incident wave angle and water depth. The time-domain analysis was carried out to evaluate the response of the floating foundation under a selected operational condition. The hydrodynamic performances of this floating foundation with respect to time series and response spectra were also investigated in this study. 相似文献