首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   209篇
  免费   5篇
  国内免费   6篇
教育   172篇
科学研究   25篇
各国文化   2篇
体育   6篇
文化理论   1篇
信息传播   14篇
  2023年   3篇
  2022年   10篇
  2021年   13篇
  2020年   9篇
  2019年   20篇
  2018年   13篇
  2017年   20篇
  2016年   11篇
  2015年   9篇
  2014年   10篇
  2013年   33篇
  2012年   9篇
  2011年   10篇
  2010年   4篇
  2009年   6篇
  2008年   7篇
  2007年   3篇
  2006年   7篇
  2005年   2篇
  2003年   2篇
  2002年   3篇
  1997年   1篇
  1996年   2篇
  1993年   1篇
  1992年   1篇
  1990年   2篇
  1987年   1篇
  1985年   2篇
  1984年   2篇
  1981年   1篇
  1980年   1篇
  1976年   1篇
  1940年   1篇
排序方式: 共有220条查询结果,搜索用时 0 毫秒
121.
This paper argues against a view of curriculum as a means for moulding students into, and making teachers accountable for, something pre‐determined and singularly governed by qualification demands of the labour market. It makes a case for the value of inter‐subjective teacher–student relationships in education and addresses the significance of negotiations and their open‐endedness. This paper draws its empirical material from case studies for which interviews were the main source for gathering data. The data analyses were made using the AtlasTi software designed for qualitative analysis. In the empirical material were found instances of negotiations in which inter‐subjective relationships are established and maintained; negotiations that are rendered obscured or even invisible from a qualification purpose but that influence the educational processes. The results show that teachers and students creatively use potentials within contextual conditions to attain relationships which sometimes constitute a precondition for education.  相似文献   
122.
In this study, a Surface Computer Supported Cooperative Work paradigm is proposed. Recently, multitouch technology has become widely available for human–computer interaction. We found it has great potential to facilitate more awareness of human-to-human interaction than personal computers (PCs) in colocated collaborative work. However, other studies and modern operating systems have rarely been concerned with colocated interactions in their user interface (UI) design. Therefore, one UI framework, which we have named Surface Application Framework (SAF), is proposed to support multitouch and multiuser applications on tabletop computers. To explore the effects of wide area SAFs on colocated collaboration, one application, capable of making English sentences, was developed based on an SAF. This application was used to conduct a user-centric study to investigate differences between surface computers and PCs. The results show that a surface computer performs better than a PC in creating awareness during collaborative work, but it requires more time due to its poor performance with drag-and-drop operations. Finally, this study summarizes a three-dimensional design approach to consider various trade-offs between awareness and manipulative performances. Additionally, some mechanisms are suggested to be employed to overcome the weakness of drag-and-drop operations with multitouch interfaces in a future study.  相似文献   
123.
124.
In this paper we present a method for testing the Hurwitz property of a segment of polynomials (1−λ)p0(s)+λp1(s), where λ∈[0,1] and p0(s) and p1(s) are nth-degree polynomials with complex coefficients. The method consists in constructing a parametric Routh-like array with polynomial entries and generating Sturm sequences for checking the absence of zeros of two real λ-polynomials of degrees 2 and 2n in the interval (0,1). The presented method is easy to implement. Moreover, it accomplishes the test in a finite number of arithmetic operations because it does not invoke any numerical root-finding procedure.  相似文献   
125.
This study investigated students’ modeling progress and strategies in a problem-solving simulation game through content analysis, and through supervised and unsupervised lag sequential analysis (LSA). Multiple data sources, including self-report models and activity logs, were collected from 25 senior high school students. The results of the content analysis found that the problem-solving simulation game helped most of the students to reflectively play with the science problem and build a workable model to solve it. By using the supervised LSA, it was found that the students who successful solved the game frequently linked the game contexts with the physics terminologies, while those who did not solve the problem simply relied on the intuitive knowledge provided in the reference materials. Furthermore, the unsupervised LSA identified four activity patterns that were not noticed in the supervised LSA: the fragmented, reference material centered, reference material aided modeling, and modeling centered patterns. Each pattern has certain associations with certain problem-solving outcomes. The results of this study also shed light on the use of different analytics techniques. While the supervised LSA is particularly helpful for depicting a contrast of activity patterns between two specific student groups, the unsupervised LSA is able to identify hidden significant patterns which were not clearly distinguished in the pre-defined student groups. Researchers may find these analytics techniques useful for analyzing students’ learning processes.  相似文献   
126.
The effects of process variables such as enzyme types, enzyme ratio, reaction temperature, pH, time, and ethanol concentration on the extraction of unripe apple polyphenol were investigated. The results indicated that Viscozyme L had the strongest effect on polyphenols extraction and was selected to study the polyphenol composition. The ratio of enzyme (Viscozyme L) to substrate (2 fungal beta-glucanase units (FBG)) at 0.02, reaction at pH 3.7,50 ℃ for 12 h, and ethanol concentration of 70% were chosen as the most favorable extraction condition. Total phenolic content (TPC), reducing sugar content (RSC), and extraction yield increased by about 3,1.5, and 2 times, respectively, compared with control. The contents of p-coumaric acid, ferulic acid, and caffeic acid increased to 8,4, and 32 times, respectively. The enzyme-aided polyphenol extraction process from unripe apples might be applied to food industry for enhancing bioactive compound production.  相似文献   
127.
Many efforts have been made to reach educational equity, especially to reduce mathematics and science achievement gaps by students’ socioeconomic status. Across countries, educators strive to reform traditional teacher-centered instructional approaches to more student-centered/inquiry-based instruction to improve equity in education. In this context, this study examines whether relationships between socioeconomic status and scientific or mathematical literacy are moderated by student-centered instruction. Ten countries covering a wide range of achievement levels as well as equity in education are selected for an international comparison. A linear regression analysis is applied to student achievement, equity, and frequency of student-centered instruction data from the PISA 2012 and PISA 2015. We find mixed results: As student-centered instruction is offered more frequently, the gap in mathematical and scientific literacy between low and high socioeconomic status is generally narrowed or maintained. In most countries, students’ mathematical and scientific literacy scores are expected to decrease across all socioeconomic status as student-centered instruction is given more frequently. The findings necessitate further scrutiny of how teachers implement student-centered instruction in various educational systems. This further research need to consider the complexity of implementation related to sociological and pedagogical aspects.  相似文献   
128.
For diverse multiple access communication systems based on frame slotted aloha (FSA) protocol, it is important to analyze collision probability for the system performance evaluation. As shown in the literature, for general settings, it is difficult to derive an exact and closed-form solution for collision probability without approximation. Recently, an exact solution based on generic analytical approach (GAA) [31] has been proposed, yet its numerical computation will become difficult when the number of slots is larger than 16. In this paper, we develop an exact closed-form formula (ECFF) for collision probability that can not only overcome the computational deficiency of GAA in the presence of a large number of slots, but also reduce the computation complexity of collision probability. Surprisingly, by introducing a differentiation operator to form a hybrid recursive equation and applying various algebraic properties of Laplace transform and Z transform, the final collision probability can be represented by a compact double summation. Accuracy of the ECFF and comparison with the GAA have been studied by Monte Carlo simulation.  相似文献   
129.
Quantum information theory holds the promise of revolutionizing technologies other than computing and communications. In this article we show how quantum entanglement can be harnessed to beat the Rayleigh diffraction limit of conventional optical lithography, and to permit nano-devices to be fabricated at a scale arbitrarily shorter than the wavelength used. Given the relative ease of performing optical lithography compared with other schemes, and the relative costs associated in migrating the lithography industry to each new fabrication technology, exploiting quantum entanglement to extend the useful life of optical lithography could be economically attractive.  相似文献   
130.
International Review of Education - Drawing on critical theory for adult education, the authors of this article examine the Academic Credit Bank System (ACBS), an open educational system operating...  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号