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101.
In this study we investigated the influence of text modality on learning with static and dynamic visualizations in a dynamic domain, namely the physical principles underlying fish locomotion. A 2 × 2-design with type of visualization (static vs. dynamic) and text modality (spoken vs. written) as independent variables was used. Concerning learning outcomes, it was hypothesized that (1) learners presented with dynamic visualizations would outperform learners presented with static visualizations, (2) learners presented with spoken text would outperform learners presented with written text, and (3) an interaction between type of visualization and modality would occur: the superiority of dynamic over static visualizations was expected to be more pronounced for spoken compared to written text. Subjective cognitive load measures were assessed and expected to mirror the aforementioned pattern of learning outcomes in accordance with Cognitive Load Theory (i.e., higher extraneous cognitive load (ECL) related to lower learning outcomes). For transfer tasks, the first two hypotheses could be confirmed. However, there was no interaction. Moreover, ECL was rated higher by subjects when learning with static compared to dynamic visualizations, but there were no differences for ECL with respect to the text modality. The results are discussed within the framework of Cognitive Load Theory.  相似文献   
102.
Many animations impose a high cognitive load due to the transience of information, which often hampers learning. Segmentation, that is presenting animations in pieces (i.e., segments), has been proposed as a means to reduce this high cognitive load. The expertise reversal effect shows, however, that design measures that have a positive effect on cognitive load and learning for students with lower levels of prior knowledge, might not be effective, or might even have a negative effect on cognitive load and learning for students with higher levels of prior knowledge. This experiment with animated worked-out examples showed an expertise reversal effect of segmentation: segmented animations were more efficient than continuous animations (i.e., equal test performance with lower investment of mental effort during learning) for students with lower levels of prior knowledge, but not for students with higher levels of prior knowledge.  相似文献   
103.
To have a quality multimedia presentation through networks, its presentation lag needs to be controlled. One way to reduce the lag is to prefetch the media objects before their due dates. This paper explores techniques for optimizing the object sequence in a prefetch-enabled TV-like presentation. An optimal solution is the one with which the presentation lag is minimized. We formulate the problem into a two-machine flowshop scheduling problem with a single chain precedence constraint and a player-side buffer constraint. The player-side buffer is “processing time-dependent” and distinguished from the conventional item-based intermediate buffer constraints discussed in previous flowshop studies. We prove the problem to be strongly NP-hard. A branch and bound algorithm equipped with four lower bounds and an NEH-based upper bound is developed. The simulation results show that the average gaps between the overall lower bounds and the NEH-based upper bound are less than 3% for problems with a large buffer size, and less than 13% for problems with a small buffer size and high density of precedence constraints. For applications where the media objects are delivered through extremely busy servers with which only very restricted CPU resources can be allocated for computation, the CDS-based algorithm provides better sequences than the NEH-based algorithm.  相似文献   
104.
Advances in e-learning technologies parallels a general increase in sophistication by computer users. The use of just one theory or model, such as the technology acceptance model, is no longer sufficient to study the intended use of e-learning systems. Rather, a combination of theories must be integrated in order to fully capture the complexity of e-learners, who are both system users and learners. The current research presents an integrated theoretical framework to study users’ acceptance of streaming media for e-learning. Three streams of research provide the basis for this integrated framework: the technology acceptance model, flow theory and media richness theory. Students enrolled in an online section of an information systems course used one of three different combinations of text, streamed audio and streamed video. Regression analysis was used to test the hypotheses in this field experiment. Perceived ease of use was a predictor of perceived usefulness; both the perceived usefulness and the attitude of the user were predictors of intention to use. Richer content-presentation types were positively correlated with higher concentration levels but showed mixed results when correlated with perceived usefulness. Results from this study have practical implications for those interested in integrating streaming media into e-learning.  相似文献   
105.
The aim of this study was to assess the learning effectiveness and motivational appeal of a computer game for learning computer memory concepts, which was designed according to the curricular objectives and the subject matter of the Greek high school Computer Science (CS) curriculum, as compared to a similar application, encompassing identical learning objectives and content but lacking the gaming aspect. The study also investigated potential gender differences in the game’s learning effectiveness and motivational appeal. The sample was 88 students, who were randomly assigned to two groups, one of which used the gaming application (Group A, N = 47) and the other one the non-gaming one (Group B, N = 41). A Computer Memory Knowledge Test (CMKT) was used as the pretest and posttest. Students were also observed during the interventions. Furthermore, after the interventions, students’ views on the application they had used were elicited through a feedback questionnaire. Data analyses showed that the gaming approach was both more effective in promoting students’ knowledge of computer memory concepts and more motivational than the non-gaming approach. Despite boys’ greater involvement with, liking of and experience in computer gaming, and their greater initial computer memory knowledge, the learning gains that boys and girls achieved through the use of the game did not differ significantly, and the game was found to be equally motivational for boys and girls. The results suggest that within high school CS, educational computer games can be exploited as effective and motivational learning environments, regardless of students’ gender.  相似文献   
106.
The objective of this study is to assess the effectiveness of the educational environment supported by computer aided presentations at primary school. The effectiveness of the environment has been evaluated in terms of students’ learning and remembering what they have learnt. In the study, we have compared experimental group and control group in terms of learning and recalling what has been learned regarding the effect which computer aided learning environment imposes. Data have been collected through the control grouped pretest–final test model. During the experiment, we have prepared an achievement test, which explains behaviors the students should acquire. According to the findings obtained, a computer aided educational environment has been observed to be more effective than that of conventional education in terms of learning. However, in terms of the permanence of what has been learned, no meaningful difference between the educational environment supported by computer aided presentations and that of conventional education has come out. According to the results of the follow-up tests performed, even though students in the test group have forgotten more of what they have learnt, it has been concluded that students in both groups have forgotten on the same level. Consequently, it has been observed that though the educational environment supported by computer aided presentations has positive contributions to learning activity, it does not have effects on the permanence of what has been learnt.  相似文献   
107.
This study examined business students’ perceptions of four objectives (i.e., Enjoyment, Learning, Motivation, and Career Application) across five teaching technologies (i.e., Projector, PowerPoint, Video, the Internet, and Lecture), business professors’ effective application of technologies, and students’ academic performance. We collected data from 215 students at a regional state university in the USA. We developed Students’ Perceptions of Technology Scale, SPOTS, specifically for the present study, used the most rigorous criteria, and investigated reliability, convergent and discriminant validity, exploratory and confirmatory factor analysis, and measurement invariance of this scale. Mean scores revealed that Video conveyed the highest amount of Enjoyment. PowerPoint provided the highest amount of Learning and Motivation. The Internet provided the highest Career Application for future jobs. Younger students preferred Video, whereas older students favored Lecture. Regression results showed that the use of Video for Learning, Projector and Lecture for Enjoyment, PowerPoint for career and Motivation, and the Internet for Learning contributed to professors’ teaching effectiveness. Students’ high ratings for professors’ effective use of the Lecture method and low expectation for the use of a Projector predicted their self-reported GPA (academic performance). Professors may use a different mix of technologies in the classroom and use them creatively in order to promote the most Learning for students and satisfy students’ Learning needs and objectives.  相似文献   
108.
The management of large collections of music data in a multimedia database has received much attention in the past few years. In the majority of current work, researchers extract the features, such as melodies, rhythms, and chords, from the music data and develop indices that will help to retrieve the relevant music quickly. Several reports have pointed out that these music features can be transformed and represented in forms of music feature strings or numeric values so that indices can be created for music retrieval. However, there are only a small number of existing approaches which introduce multi-feature index structures for music queries while most of the others are for developing single feature indices. The existing music multi-feature index structures are memory consuming and have lack of scalability. In this paper, we will propose a two-tier music index structure which is an efficient and scalable approach for multi-feature music indexing. Our experimental results show that this new approach outperforms existing multi-feature index schemes.  相似文献   
109.
基于IMS的移动多媒体广播时移系统信令设计   总被引:2,自引:0,他引:2       下载免费PDF全文
提出一种基于IMS的移动多媒体广播时移系统架构,该架构融合广播网络和无线移动通信网络,为移动多媒体广播提供时移服务,实现服务与接入无关。设计基于SIP的时移信令流程来完成对时移业务的支撑。利用排队论方法对时移请求信令延迟进行理论分析,结果表明信令延迟能够满足实时性需求,证明该系统是完全可行的。  相似文献   
110.
针对目前教学中多媒体课件的不足和程序的演示不能同步等问题.设计制作教学演示系统,该系统将程序演示和多媒体课件有机融合并同步显示,将理论和实践紧密结合,更好地帮助学生理解课堂教学内容,有效改善课堂效果和提高教学效率,同时具有良好的可扩充性。  相似文献   
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