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1.
The number of incidents due to reactive hazards demonstrate the need of training for professionals and for students in the field of Thermal Process Safety. The specific difficulty in this field is that the assessment of thermal risks requires knowledge in physical chemistry as well as engineering knowledge. Hence, in order to teach this knowledge, it must first be simplified. The strongly non-linear behaviour of reactors in runaway situations also requires specific teaching methods. Different didactic tools are presented: case histories, numerical simulation, building a tool box (MS-Excel), E-Learning, Thermal Process Safety App, role game with a virtual laboratory are presented. The text concludes with some considerations on teaching professionals in the industry and students in universities.  相似文献   
2.
随着教育信息化技术的发展,线上线下混合式教学模式已成为一种趋势。为了解决非全日制研究生课堂教学召集困难、效果不佳等问题,提出了基于“互联网+虚拟仿真技术”的线上线下混合式教学模式。本文以控制工程专业学位研究生为例,结合《现代电气控制技术》课程,探讨了线上线下混合式教学实现途径、师生互动方法、项目驱动案例教学法以及电气控制系统虚拟仿真实验平台的构建方法,切实提升非全日制研究生的培养质量。  相似文献   
3.
360° VR videos provide users with an immersive visual experience. To encode 360° VR videos, spherical pixels must be mapped onto a two‐dimensional domain to take advantage of the existing video encoding and storage standards. In VR industry, standard cubemap projection is the most widely used projection method for encoding 360° VR videos. However, it exhibits pixel density variation at different regions due to projection distortion. We present a generalized algorithm to improve the efficiency of cubemap projection using polynomial approximation. In our algorithm, standard cubemap projection can be regarded as a special form with 1st‐order polynomial. Our experiments show that the generalized cubemap projection can significantly reduce the projection distortion using higher order polynomials. As a result, pixel distribution can be well balanced in the resulting 360° VR videos. We use PSNR, S‐PSNR and CPP‐PSNR to evaluate the visual quality and the experimental results demonstrate promising performance improvement against standard cubemap projection and Google's equi‐angular cubemap.  相似文献   
4.
Enhancing the earthquake behavioral responses and post-earthquake evacuation preparedness of building occupants is beneficial to increasing their chances of survival and reducing casualties after the mainshock of an earthquake. Traditionally, training approaches such as seminars, posters, videos or drills are applied to enhance preparedness. However, they are not highly engaging and have limited sensory capabilities to mimic life-threatening scenarios for the purpose of training potential participants. Immersive Virtual Reality (IVR) and Serious Games (SG) as innovative digital technologies can be used to create training tools to overcome these limitations. In this study, we propose an IVR SG-based training system to improve earthquake behavioral responses and post-earthquake evacuation preparedness. Auckland City Hospital was chosen as a case study to test our IVR SG training system. A set of training objectives based on best evacuation practice has been identified and embedded into several training scenarios of the IVR SG. Hospital staff (healthcare and administrative professionals) and visitors were recruited as participants to be exposed to these training scenarios. Participants’ preparedness has been measured along two dimensions: 1) Knowledge about best evacuation practice; 2) Self-efficacy in dealing with earthquake emergencies. Assessment results showed that there was a significant knowledge and self-efficacy increase after the training. In addition, participants acknowledged that it was easy, helpful, and engaging to learn best evacuation practice knowledge through the IVR SG training system.  相似文献   
5.
Evidence suggests that transient visual information, such as animations, may be more challenging to learn than static visualizations. However, when a procedural-manipulative task is involved, our evolved embodied cognition seems to reverse this transitory challenge. Hence, for object manipulative tasks, instructional animations may be more suitable than statics. We investigated this argument further by comparing animations with statics using a Lego task shown to university students, by examining three potential moderators of effectiveness: (a) the environment of manipulation (virtual or physical), (b) the quality of visual information (focused or unfocused), and (c) the presence of hands (no hands or with hands). In Experiment 1 we found an advantage of animation over statics, and no differences among the environments. In Experiment 2, we again observed an animation advantage, a small advantage of focused static information compared to unfocused static information, and a positive effect of not showing the hands.  相似文献   
6.
As technology advances, robots and virtual agents will be introduced into the home and healthcare settings to assist individuals, both young and old, with everyday living tasks. Understanding how users recognize an agent׳s social cues is therefore imperative, especially in social interactions. Facial expression, in particular, is one of the most common non-verbal cues used to display and communicate emotion in on-screen agents (Cassell et al., 2000). Age is important to consider because age-related differences in emotion recognition of human facial expression have been supported (Ruffman et al., 2008), with older adults showing a deficit for recognition of negative facial expressions. Previous work has shown that younger adults can effectively recognize facial emotions displayed by agents (Bartneck and Reichenbach, 2005, Courgeon et al., 2009, Courgeon et al., 2011, Breazeal, 2003); however, little research has compared in-depth younger and older adults’ ability to label a virtual agent׳s facial emotions, an import consideration because social agents will be required to interact with users of varying ages. If such age-related differences exist for recognition of virtual agent facial expressions, we aim to understand if those age-related differences are influenced by the intensity of the emotion, dynamic formation of emotion (i.e., a neutral expression developing into an expression of emotion through motion), or the type of virtual character differing by human-likeness. Study 1 investigated the relationship between age-related differences, the implication of dynamic formation of emotion, and the role of emotion intensity in emotion recognition of the facial expressions of a virtual agent (iCat). Study 2 examined age-related differences in recognition expressed by three types of virtual characters differing by human-likeness (non-humanoid iCat, synthetic human, and human). Study 2 also investigated the role of configural and featural processing as a possible explanation for age-related differences in emotion recognition. First, our findings show age-related differences in the recognition of emotions expressed by a virtual agent, with older adults showing lower recognition for the emotions of anger, disgust, fear, happiness, sadness, and neutral. These age-related difference might be explained by older adults having difficulty discriminating similarity in configural arrangement of facial features for certain emotions; for example, older adults often mislabeled the similar emotions of fear as surprise. Second, our results did not provide evidence for the dynamic formation improving emotion recognition; but, in general, the intensity of the emotion improved recognition. Lastly, we learned that emotion recognition, for older and younger adults, differed by character type, from best to worst: human, synthetic human, and then iCat. Our findings provide guidance for design, as well as the development of a framework of age-related differences in emotion recognition.  相似文献   
7.
The effects of physical embodiment and physical presence were explored through a survey of 33 experimental works comparing how people interacted with physical robots and virtual agents. A qualitative assessment of the direction of quantitative effects demonstrated that robots were more persuasive and perceived more positively when physically present in a user׳s environment than when digitally-displayed on a screen either as a video feed of the same robot or as a virtual character analog; robots also led to better user performance when they were collocated as opposed to shown via video on a screen. However, participants did not respond differently to physical robots and virtual agents when both were displayed digitally on a screen – suggesting that physical presence, rather than physical embodiment, characterizes people׳s responses to social robots. Implications for understanding psychological response to physical and virtual agents and for methodological design are discussed.  相似文献   
8.
An innovative teaching methodology, which incorporates all the advantages offered separately by WebQuest (an inquiry-oriented lesson format in which most or all the information that learners work with comes from the web), CLIL (Content Language Integrated Learning) and STSE (Science, Technology, Society and Environment) was developed to integrate real bioreactor experiments to produce ecological bioethanol with virtual bioreactor computer simulation. Thus, by means of this type of WebQuest, it is possible to connect STSE real laboratory sessions in a Spanish university with CLIL sessions in English in a virtual foreign laboratory through the Internet introducing students to the international scientific world.This teaching approach can be very helpful solving the common problem of limited time to conduct enough applied practical contents, it empowers independent work of students and it is technologically adapted to the times we live.The effectiveness of the implemented system was obtained by evaluation through direct experimentation, assessment (with a rubric for the laboratory session reports and a written test) and survey (through a questionnaire) with 40 undergraduate students. All these results show that students are more motivated and learn more following this kind of laboratory sessions.  相似文献   
9.
The evaluation of functional features of manufactured workpieces is based on GO- and NO-GO-test results, which are obtained by comparing measured geometric characteristics with nominal dimensions and tolerances specified by the designer. These geometrical specifications are based on a tolerancing system, which was originally defined for the function mating capability. Against the background of upcoming lots of other new functions (like reduction of flow resistance, light absorption, reduction of friction, diffraction of light, self-cleaning or mass transmission) are to be realized with our products – particularly by micro- and nano scaled features. If the verification process will deliver the prediction of the achievable degree of functionality, the usability of a part can be assessed more accurately and in consequence quality and economics can be improved. So, a new principle for tolerancing and verifying turns out to be necessary. In this paper the fundamental deficit of the actual tolerancing and specification systems GPS and ASME Y14.5 is derived and the path for enlarging the system by preposing a functional model is shown. To verify the functional capability of the workpieces an approach based on simulations done with the parameterized mathematical–physical model of the function is suggested. Advantages of this approach will be discussed and demonstrated by examples with microstructured inking rolls, crankshafts and injection valves.  相似文献   
10.
Communities of practice are nowadays an important concept in the healthcare sector. Particularly, the intensive use of ICT has allowed their creation into a virtual environment – Virtual Communities of Practice (VCoPs) developing optimal conditions to make possible the collaborative learning process. The VCoPs antecedents can be situated on social network phenomenon, where individuals with different traits but a common interest/objective are linked, use ICT potency (especially social media) to interchange information, experiences and contents among them. And as a result, people create and share knowledge, and learn collaboratively. VCoP users have a higher satisfaction level in the collaborative learning process when they can: (1) Achieve benefits related to patient diagnosis and treatment (cost reductions, faster management, quality and accuracy of diagnosis, etc.); (2) Increase the share capital of participants and creating networks of trusted individuals. Given the interest in this topic, the objective of this work is to identify the factors that determine user satisfaction in relation to Community Practice (CoP) and the process of building shared knowledge. For this, a sample of 130 Spanish health professionals participating in an online community, and developed in a virtual community of practice, is discussed. The results obtained from an analysis of logistic regression show evidence of the perception of efficiency and effectiveness in collaboration with the members of the VCoP as positively influencing the perceived satisfaction with the CoP. Also, the degree of individual participation in the community affects the degree of perceived satisfaction. The conclusions provide interesting strategic recommendations in the management process of the CoP.  相似文献   
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