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81.
This study assessed the effect of design instructional video based on the Cognitive Theory of Multimedia Learning by applying segmentation and signaling on the learning outcome of students in an online technology integration course. The study assessed the correlation between students’ personal preferences (preferred learning styles and area of specialization) and their learning outcomes. A three-group pretest–posttest design was employed to assess whether there were significant differences in students’ test scores after they watched an instructional video. The results of the analysis of covariance (ANCOVA) analysis indicate that instructional design had a significant effect on students’ learning outcome. This effect was demonstrated by the statistically significant differences in students’ learning outcomes, with the highest scores achieved by students in the segmented and signaled video group and the lowest scores in the no-segmentation and no-signaling group. Moreover, results indicate that students’ learning preferences and area of specialization related significantly and positively to their learning outcomes. These findings suggest that the use of educational video in online courses has the potential to effectively improve students’ learning outcome; however, it requires design manipulation. The results also emphasize the importance of rethinking the one-size-fits-all approach in developing online course content and include consideration of the students’ learning preferences and area of specialization to optimize their learning.  相似文献   
82.
The present drinking water purification system in Egypt Uses surface water as a raw water supply without a pre-liminary filtration process.On the other hand,chlorine gas iS added as a disinfectant agent in two steps,pre- and post.chlorination.Due to these reasons most of water treatment plants suffer low fltering effectiveness and produce the trihalomethane (THM) species as a chlorination by-product.The Ismailia Canal represents the most distal downstream of the main Nile Rivet.ThUS its water contains all the proceeded pollutants discharged into the Nile.In addition.the downstream reaches of the canal act as an agricultural drain during the closing period of the High Dam gates in January and February every year.Moreover,the wide in-dustrial zone along the upstream course of the carlal enriches the canal water with high concentrations of heavy metals.The obtained results indicate that the canal gains up to 24.06×106m3 of water from the surrounding shallow aquifer during the closing period ofthe High Dam gates,while during the rest ofthe year,the callal acts as an influent stream losing about 99.6×106m3 of its water budget.The reduction oftotaI organic carbon(TOC) and suspended particulate mattes(SPMs)should be one of the central goals of any treatment plan to avoid the disinfectants by-products.The combination of sedimentation basins.gravel pre-filtration and slow sand filtration,and underground passage with microbiological oxidation-reduction and adsorption criteria showed good removal of parasites and bacteria and complete elimination of TOC.SPM and heavy metals.Moreover,it reduces the use of disinfectants chemicals and lowers the treatment costs.However,this purification system under the arid climate prevailing in Egypt should be tested and modified prior to application.  相似文献   
83.
How girls and boys take decisions in the presence and absence of a teacher – This work is part of an innovative approach to physical and sports education in Tunisia, and team sports in particular. It uses language studies carried out within the framework of this teaching both to generate a reflective attitude on the part of students, and to identify the effect of gender as a variable in the ways in which they make decisions. Discourse analysis highlights the importance of language output by girls and boys in football teaching when a teacher is present or absent. The teacher is an institutional authority who imposes specific uses of language, and when he/she is absent, emotional tensions predominate and may reflect the repression of ideas that occurs when the teacher is present. Although girls appear to take part in the discussion, their utterances are fewer in number, and their analytical statements less effective than those of boys. Girls never gain the upper hand over boys. The study also suggests a redefinition of social role divisions on the basis of gender – masculinity and femininity.  相似文献   
84.
85.
Education and Information Technologies - E-Assessment, which is a key element in the instructional design process, plays a major role in supporting and enhancing learning. However, the current...  相似文献   
86.
Education and Information Technologies - Considering that emotions have a great impact on motivation, reasoning, and decision making, affective computing methods, that were designed to attempt to...  相似文献   
87.
ABSTRACT

This study investigated split-step timing when returning serves and whether this timing is related to neuromechanical capabilities in world-class tennis players. In Experiment 1, the split-step timing of four groups of world-class players (male and female ATP/WTA seniors, and ITF juniors) was measured on court when returning serves of the same level players. The four groups initiated the split-step at a similar time, starting around the time ball-racket contact in the serve stroke and landed when early ball-flight information was available. In Experiment 2, the neuromechanical capabilities (leg stiffness and vertical jump performance) of a group of world-class players and three groups of less-skilled tennis players were examined. The results showed an increase in leg stiffness with an increase in the level of expertise. A cross-experiment analysis in world-class male players (ATP/ITF, n = 10) revealed that the timing of initial foot movement was significantly correlated with the leg stiffness (r2 = 0.54), with later lateral step after the serve in the players who had higher stiffness. The findings support the hypothesis that world-class tennis players adapt perceptual-motor control on the basis of their neuromechanical capabilities and maximise the time before initiating their interceptive action to rely on more reliable information.  相似文献   
88.
ABSTRACT

The effects of plyometric jump training on the physical fitness of male youth (age = 10–17 years) soccer players was examined in relation to inter-set recovery intervals and the maturity of the players in a single-blind, randomized-and controlled crossover trial. Jumping tests and kicking velocities were measured before (T0), after a 6 week control period (T1), after 6 weeks of plyometrics (T2), after 6 weeks of wash-out (T3), and after a further 6 weeks of plyometrics (T4). Subjects were divided into pre- and post- peak-height-velocity (PHV) groups, and were randomly assigned to 30 s or 120 s inter-set intervals during periods T2 and T4. Any changes in jumping and maximum kicking velocities during T1 and T3, had trivial effect sizes (0.01–0.15), but small to moderate improvements (effect size = 0.20–0.99) were observed in both groups during T2 and T4. Gains in pre-PHV players were similar for the two inter-set intervals, but gains in post-PHV players were greater (p < 0.05) with an inter-set recovery of 120 s than with a 30 s recovery. We conclude that plyometric jump training improves the physical fitness of adolescents, irrespective of their maturity, but that in older individuals gains are greater with a longer inter-set recovery interval.  相似文献   
89.
Abstract

This study examines the promotion and knowledge of online patent literature search among students, librarians, and instructors to enhance university scientific output in Zanzibar. The study was guided by four key questions: What is the level of awareness of students, instructors and library staff about patent documents as source of information? To what extent do students and instructors access online patent databases? What is the library experience in training students about online patent literature searching?, and what are the challenges facing library and instructors in promoting patent literature search? The study used survey approach whereby questionnaire and interview were used to collect data. The recent literatures regarding online patent literature searching were also critically reviewed. A survey was conducted at two Universities in Zanzibar namely the State University of Zanzibar and Zanzibar University, whereby 20 library staff, 10 instructors and 140 undergraduate students from the School of Computing and the Faculty of Engineering were involved in this study. The findings show that more than three quarters of respondents were either partially aware or not aware at all about the existence of free online patent databases. Likewise, the majority of students had no enough skills of patent literature searching. However, usually the library organizes training on general online literature searching skills but patent literature searching was not effectively taught and a big challenge observed in this study regarding promotion of patent literature searching is inadequate patent searching skills among library and instructors. Based on the findings, the study proposed several recommendations to rectify the existing problem.  相似文献   
90.
This paper presents a dynamic model to simulate the adsorption-desorption processes associated with intermittent heat pump systems. This simulation plays an important role in sizing the adsorption systems for various types of applications in the design stage. A mathematical model that is based on the control volume approach was first developed and then discretized using the finite difference implicit scheme. The equations for the conservation of mass, momentum, and energy in the bed were derived for high-pressure and low-pressure segments, including the adsorbate (refrigerant), the adsorbent (Linde 13X), and the vessel wall. A pseudo-homogeneous model for the compression system was adopted. The numerical results that describe the adsorption-desorption history were obtained. It was found that the amount of the refrigerant recovered in the desorption process at the end of the cyclic operation is smaller than the amount adsorbed during the adsorption process. This indicates that the time for the regeneration process should be longer than the time for the adsorption process in order to raise the sieve temperature. In order to compare the simulated results with experimental data, numerical values for the heat transfer coefficients were theoretically evaluated. To assure the stability of the simulated results, the incremental time of system operation is kept equal or less than the value obtained from the minimum stability requirement. The simulated results of the temperature distribution history during system operation are in good agreement with the conducted experimental results, which led to the conclusion that the model can be used as an effective tool during the design stage and for the system development.  相似文献   
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