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991.
Peer-to-Peer systems are emerging as one of the most popular Internet applications. Structured Peer-to-Peer overlay networks use identifier based routing algorithms to allow robustness, load balancing, and distributed lookup needed in this environment. However, identifier based routing that is independent of Internet topology tends to be of low efficiency. Aimed at improving the routing efficiency, the super-proximity routing algorithms presented in this paper combine Internet topology and overlay routing table in choosing the next hop. Experimental results showed that the algorithms greatly improve the efficiency of Peer-to-Peer routing. 相似文献
992.
Theories of adolescent connectedness suggest that adolescents strive to become connected by engaging with and valuing the
people, activities, and worlds in their social ecology. The purpose of this study was to examine the psychometric properties
of a measure designed to assess these worlds of connectedness among 320 junior high school students in Taiwan. The subscales
and composite scales evidenced satisfactory reliability and concurrent validity. A hypothesized three-factor, higher order
structural model of connectedness was cross-validated. Girls were generally more connected than boys. Both connectedness to
school and to friends explained more variance in connectedness to self than did family connectedness. There was mixed support
for separation-individuation processes. The measure appears promising in terms of future research on adolescent social development
in the Asia Pacific. 相似文献
993.
Education in different communication media takes place with functional differences that have consequences for the course of instructional interaction. In this paper, we examine instructional interaction among people using a computer-based electronic message system, contrasting it with conventional face-to-face discussion in a college level class. Interaction via the non-real time message system contained multiple “threads of discourse,” a higher proportion of student turns to teacher turns, and other deviations from the “initiation-response-evaluation” sequences usually found in face-to-face classroom interactions. Based on the results of our contrast, we describe ways to organize instruction using electronic message systems to take advantage of new properties and to avoid shortcomings of these new instructional media. 相似文献
994.
Law enforcement officers, often the first professionals to come in contact with a victim of child sexual abuse, can either increase or decrease the traumatic impact on the child and the family at the time of disclosure. The model for a training program for police officers in handling cases of child sexual abuse outlined in this paper is divided into three sections. The first part is directed towards theoretical issues involved in this problem, including an explanation of the history and background of sexual abuse of children by adults and of the difference in the dynamics of extra- and intrafamilial sexual abuse. The second part consists of a detailed explanation of different types of sex offenses and of standard physical examinations of sexual abuse victims. Graded slides of physical trauma geared towards wound identification are paired with relaxation exercises. The third section focuses on special considerations when interviewing sexually abused children. The difference between interviewing and interrogation, specific questioning techniques, and the use of videotape is explained. Each part of this training procedure is followed by a question and answer period and small group discussions for the purpose of encouraging disclosure and better understanding of the officers' personal reactions to cases of child sexual abuse. 相似文献
995.
Leonard?A.?AnnettaEmail author James?Minogue 《Journal of Science Education and Technology》2004,13(4):485-494
The first year of a 5 year professional development project for elementary teachers in two mid-western states integrated a bridge of two distinctly different distance education networks (T-1 and fiber optics) to provide science professional development for elementary school teachers in rural communities. Interactive television (ITV), the title given to the distance component, consisted of a series of twenty-four, 2 h presentations by scientists and content specialists. It provided expansion to the science pedagogical content knowledge of the elementary teachers involved. Eighty-five teachers in 38 school districts from the two states completed individual surveys following the final ITV session. Analysis of variance of participants post-session survey scores yielded differences (p < 0.05) on the subscales measuring perceived effectiveness of using distance education for professional development purposes and years of teaching experience. Teachers with over 20 years of classroom experience perceived the use of distance education technologies for science professional development to be more effective than teachers with 16–20 years of classroom experience. These results might suggest another digital divide. 相似文献
996.
997.
R J D Rutherford 《British journal of educational technology : journal of the Council for Educational Technology》1983,14(1):4-13
This paper describes four different approaches through which an institution can provide a programme for academic staff training and development. The advantages and disadvantages of each approach are analysed with the help of a recently developed theory which seeks to explain why some innovations are successful while others fail. This analysis may contribute towards the development of institutional strategies to ensure the survival—if not the revival—of staff development in universities in the United Kingdom. 相似文献
998.
999.
1000.
Paul A. Eniaiyeju 《科学教学研究杂志》1983,20(8):795-801
A comparison is made of the relative effectiveness of teacher-demonstration and self-paced modes of teaching concepts and problem-solving skills in chemistry. Sixty students were randomized into two treatment groups. A self-paced instructional package was used by subjects in the self-paced group. Subjects in the second group were taught by a teacher who used the same self-paced package. Results of the analyses of variance performed showed that the selfpaced mode of instruction was significantly more effective for teaching concepts and problem-solving skills. An attitude test was given at the end of the third unit. Results of the test showed that most students preferred the self-paced instruction to the teacher-demonstration method. 相似文献