全文获取类型
收费全文 | 337篇 |
免费 | 10篇 |
国内免费 | 1篇 |
专业分类
教育 | 168篇 |
科学研究 | 127篇 |
各国文化 | 4篇 |
体育 | 18篇 |
文化理论 | 2篇 |
信息传播 | 29篇 |
出版年
2023年 | 5篇 |
2022年 | 6篇 |
2021年 | 11篇 |
2020年 | 15篇 |
2019年 | 12篇 |
2018年 | 39篇 |
2017年 | 23篇 |
2016年 | 17篇 |
2015年 | 22篇 |
2014年 | 24篇 |
2013年 | 29篇 |
2012年 | 20篇 |
2011年 | 15篇 |
2010年 | 13篇 |
2009年 | 17篇 |
2008年 | 18篇 |
2007年 | 9篇 |
2006年 | 5篇 |
2005年 | 12篇 |
2004年 | 2篇 |
2003年 | 2篇 |
2002年 | 2篇 |
2001年 | 2篇 |
2000年 | 1篇 |
1998年 | 3篇 |
1996年 | 1篇 |
1994年 | 1篇 |
1990年 | 2篇 |
1988年 | 2篇 |
1987年 | 1篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1983年 | 2篇 |
1982年 | 4篇 |
1981年 | 2篇 |
1980年 | 1篇 |
1975年 | 1篇 |
1973年 | 2篇 |
1963年 | 2篇 |
1961年 | 1篇 |
排序方式: 共有348条查询结果,搜索用时 15 毫秒
341.
The present study investigated English as a foreign language (EFL) teachers’ attributions of success and failure. It also set out to investigate whether these attributions vary by teachers’ age, teaching experience, gender and educational level. To do so, 200 EFL teachers were selected according to convenience sampling among EFL teachers teaching English in Language Institutes in Mashhad and Tehran, two cities in Iran. The participants completed the language teacher attribution scale measuring four attributions: teaching competency (TC), teacher effort (TE), student effort (SE) and institution supervision (IS). The present study yielded mixed results regarding English language teachers’ attributions of success and failure events. It was also found that these attributions vary by their age, teaching experience and educational level, but not by gender. The discussion and implications of the research are further presented with reference to the earlier findings. 相似文献
342.
Neda Nasiri Ahmad Fakharian Mohammad Bagher Menhaj 《Journal of The Franklin Institute》2021,358(10):5185-5212
This paper presents a novel combined State Dependent Riccati Equation (SDRE) / Function Approximation Technique (FAT)-based control design for nonlinear uncertain systems. The SDRE is employed to construct an optimal controller and the function approximation technique is utilized to estimate time-varying disturbances and uncertainties. Moreover, a robust term in the proposed control law compensates for the truncation error. The closed-loop stability and boundedness of the tracking error and FAT weights approximation error are proved in the sense of Lyapunov, with consideration of truncation error. Due to the great importance of the adequate performance of transient response from practical point of view, performance evaluation has been accomplished. The proposed scheme is computationally simple due to utilizing the FAT to represent uncertainties and disturbances as a function of time. Compared with the SDRE based SMC, the proposed controller is superior in terms of capability to track a fast and highly complicated trajectory and no need to determine time-varying disturbances and uncertainties bounds. The case study is a Selective Compliant Articulated Robot for Assembly (SCARA) flexible joint manipulator as a representative of highly nonlinear, coupled, large robotic systems. Simulation results easily verify the effectiveness and superiority of the proposed controller. 相似文献
343.
Mohammad Allahbakhsh Haleh Amintoosi Behshid Behkamal Amin Beheshti Elisa Bertino 《Journal of Informetrics》2021,15(2):101127
In collaborative content generation (CCG), such as publishing scientific articles, a group of contributors collaboratively generates artifacts available through a venue. The main concern in such systems is the quality. A remarkable range of research considers quality metrics partially when dealing with the quality of artifacts, contributors, and venues. However, such approaches have several drawbacks. One of the most notable ones is that they are not comprehensive in terms of the metrics to evaluate all entities, including artifacts, contributors, and venues. Also, they are vulnerable to potential attacks.In this paper, we propose a novel iterative definition in which the quality of artifacts, collaborators, and venues are defined interconnectedly. In our framework, the quality of an artifact is defined based on the quality of its contributors, venue, references, and citations. The quality of a contributor is defined based on the quality of his artifacts, collaborators, and the venues. Quality of a venue is defined based on both quality of artifacts and contributors. We propose a data model, formulations, and an algorithm for the proposed approach. We also compare the robustness of our approach against malicious manipulations with two well-known related approaches. The comparison results show the superiority of our method over other related approaches. 相似文献
344.
345.
Hori Ghaneialvar Leila Soltani Hamid Reza Rahmani Abbas Sahebghadam Lotfi Masoud Soleimani 《Indian journal of clinical biochemistry : IJCB》2018,33(1):46-52
Mesenchymal stem cells are multipotent cells capable of replicating as undifferentiated cells, and have the potential of differentiating into mesenchymal tissue lineages such as osteocytes, adipocytes and chondrocytes. Such lineages can then be used in cell therapy. The aim of present study was to characterize bone marrow derived mesenchymal stem cells in four different species, including: sheep, goat, human and mouse. Human bone-marrow mesenchymal stem cells were purchased, those of sheep and goat were isolated from fetal bone marrow, and those of mouse were collected by washing bone cavity of femur and tibia with DMEM/F12. Using flow-cytometry, they were characterized by CD surface antigens. Furthermore, cells of third passage were examined for their osteogenic and adipogenic differentiation potential by oil red and alizarin red staining respectively. According to the results, CD markers studied in the four groups of mesenchymal stem cells showed a different expression. Goat and sheep expressed CD44 and CD166, and weakly expressed CD34, CD45, CD105 and CD90. Similarly, human and mouse mesenchymal cells expressed CD44, CD166, CD105 and CD90 whereas the expression of CD34 and CD45 was negative. In conclusion, although all mesenchymal stem cells display plastic adherence and tri-lineage differentiation, not all express the same panel of surface antigens described for human mesenchymal stem cells. Additional panel of CD markers are necessary to characterize regenerative potential and possible application of these stem cells in regenerative medicine and implantology. 相似文献
346.
Bandur Agustinus Hamsal Mohammad Furinto Asnan 《Educational Research for Policy and Practice》2022,21(1):85-107
Educational Research for Policy and Practice - Since 2001, Indonesian schools have implemented a mandatory school-based management (SBM) policy for better quality education in general and more... 相似文献
347.
348.
Qinyi Liu Mohammad Khalil 《British journal of educational technology : journal of the Council for Educational Technology》2023,54(6):1715-1747
The field of learning analytics has advanced from infancy stages into a more practical domain, where tangible solutions are being implemented. Nevertheless, the field has encountered numerous privacy and data protection issues that have garnered significant and growing attention. In this systematic review, four databases were searched concerning privacy and data protection issues of learning analytics. A final corpus of 47 papers published in top educational technology journals was selected after running an eligibility check. An analysis of the final corpus was carried out to answer the following three research questions: (1) What are the privacy and data protection issues in learning analytics? (2) What are the similarities and differences between the views of stakeholders from different backgrounds on privacy and data protection issues in learning analytics? (3) How have previous approaches attempted to address privacy and data protection issues? The results of the systematic review show that there are eight distinct, intertwined privacy and data protection issues that cut across the learning analytics cycle. There are both cross-regional similarities and three sets of differences in stakeholder perceptions towards privacy and data protection in learning analytics. With regard to previous attempts to approach privacy and data protection issues in learning analytics, there is a notable dearth of applied evidence, which impedes the assessment of their effectiveness. The findings of our paper suggest that privacy and data protection issues should not be relaxed at any point in the implementation of learning analytics, as these issues persist throughout the learning analytics development cycle. One key implication of this review suggests that solutions to privacy and data protection issues in learning analytics should be more evidence-based, thereby increasing the trustworthiness of learning analytics and its usefulness.
Practitioner notes
What is already known about this topic- Research on privacy and data protection in learning analytics has become a recognised challenge that hinders the further expansion of learning analytics.
- Proposals to counter the privacy and data protection issues in learning analytics are blurry; there is a lack of a summary of previously proposed solutions.
- Establishment of what privacy and data protection issues exist at different phases of the learning analytics cycle.
- Identification of how different stakeholders view privacy, similarities and differences, and what factors influence their views.
- Evaluation and comparison of previously proposed solutions that attempt to address privacy and data protection in learning analytics.
- Privacy and data protection issues need to be viewed in the context of the entire cycle of learning analytics.
- Stakeholder views on privacy and data protection in learning analytics have commonalities across contexts and differences that can arise within the same context. Before implementing learning analytics, targeted research should be conducted with stakeholders.
- Solutions that attempt to address privacy and data protection issues in learning analytics should be put into practice as far as possible to better test their usefulness.