首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   3791篇
  免费   381篇
  国内免费   196篇
电工技术   82篇
综合类   383篇
化学工业   37篇
金属工艺   74篇
机械仪表   310篇
建筑科学   209篇
矿业工程   110篇
能源动力   18篇
轻工业   38篇
水利工程   33篇
石油天然气   21篇
武器工业   59篇
无线电   278篇
一般工业技术   267篇
冶金工业   103篇
原子能技术   13篇
自动化技术   2333篇
  2024年   18篇
  2023年   77篇
  2022年   106篇
  2021年   169篇
  2020年   180篇
  2019年   92篇
  2018年   87篇
  2017年   103篇
  2016年   94篇
  2015年   95篇
  2014年   194篇
  2013年   204篇
  2012年   189篇
  2011年   213篇
  2010年   191篇
  2009年   242篇
  2008年   278篇
  2007年   270篇
  2006年   286篇
  2005年   250篇
  2004年   221篇
  2003年   189篇
  2002年   166篇
  2001年   127篇
  2000年   92篇
  1999年   85篇
  1998年   60篇
  1997年   28篇
  1996年   21篇
  1995年   14篇
  1994年   9篇
  1992年   3篇
  1991年   1篇
  1990年   2篇
  1989年   3篇
  1986年   1篇
  1985年   2篇
  1958年   2篇
  1956年   1篇
  1955年   2篇
  1954年   1篇
排序方式: 共有4368条查询结果,搜索用时 0 毫秒
1.
ABSTRACT

The concept of digital game-based learning (DGBL) evolves rapidly together with technological enhancements of virtual reality (VR) and smart phones. However, the mental workload (MWL) that VR-training applications demand and motivational qualities originating from user experience (UX) should be identified in order to create effective and enjoyable training/learning challenges that fit with individual users’ capabilities. This study examined the effects of reality-based interaction (RBI) and VR on measures of student motivation and MWL, in a mental arithmetic game for secondary school pupils. In a randomised controlled trial with sixty school children, a mental arithmetic game was tested with three different interaction and two different presentation methods – VR RBI, VR head-mounted-display tapping and tablet flick-gesture. Results found a significant effect of RBI on MWL but no differences in enjoyment of training were found between VR-experience and tablet training-experience. In fact, adding the gaming-context to the mental arithmetic task created an enjoyable, motivating experience regardless of presentation or interaction-style.  相似文献   
2.
Internet环境下漫游系统中的视点控制技术   总被引:3,自引:0,他引:3  
在研究了基于Web的虚拟真实漫游系统的应用前景的基础上,利用VRML的网络特性以及内置接口语言Java和JavaScript,对系统中的视点绑定、视点动画交互等关键技术进行了详细的阐述,并给出了相应的VRML程序。  相似文献   
3.
In this paper, we present the findings from an extensive study of the use of virtual reality (VR) models in large construction projects. The study includes two parts: The first part presents a quantitative questionnaire designed to investigate how VR models are experienced and assessed by the workforce at a building site. The second part includes a qualitative field survey of how VR models can be applied and accepted by professionals in the design and planning process of a large pelletizing plant. Through mainly studying persons who had little or no experience with advanced information technology (IT), we hoped to reveal the attitudes of the average person working at a construction site rather than of an IT expert. In summary, the study shows that the VR models in both projects have been very useful and well accepted by the users. Today’s information flow is, from a general point of view, considered to be insufficient and the hypothesis is that using VR models in the construction process have the potential to minimize waste of resources and improve the final result.  相似文献   
4.
In 3 experiments, the authors investigated spatial updating in augmented reality environments. Participants learned locations of virtual objects on the physical floor. They were turned to appropriate facing directions while blindfolded before making pointing judgments (e.g., "Imagine you are facing X. Point to Y"). Experiments manipulated the angular difference between the learning heading and the imagined heading and between the actual heading and the imagined heading. The effect of actual-imagined on pointing latency was observed for naive users but not for users with brief training or instructions concerning the fact that objects can move with body movements. The results indicated that naive users used an environment-stabilized reference frame to access information arrays, but with experience and instruction the nature of the representation changed from an environment stabilized to a body stabilized reference frame. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
5.
We present a new post processing method of simulating depth of field based on accurate calculations of circles of confusion. Compared to previous work, our method derives actual scene depth information directly from the existing depth buffer, requires no specialized rendering passes, and allows easy integration into existing rendering applications. Our implementation uses an adaptive, two‐pass filter, producing a high quality depth of field effect that can be executed entirely on the GPU, taking advantage of the parallelism of modern graphics cards and permitting real time performance when applied to large numbers of pixels.  相似文献   
6.
论述了一个网络化,信息化实验系统开发的方法和思路。该系统以虚拟技术为支撑,以图学教育的宗旨为核心,综合利用了虚拟技术的各种开发工具和理论,具有虚拟现实系统常有的特点,沉浸感,交互性,构想。  相似文献   
7.
基于ARToolkit Plus的增强现实系统实现及框架研究   总被引:1,自引:0,他引:1  
文章首先对基于ARToolkit Plus和WPF的增强现实系统实现的关键技术问题进行了描述,具体讨论了在MVC框架下如何将数据采集层与呈现层进行分划,在保证可用性的同时提供较强的扩展能力,并基于上述框架实现了一个应用于住房装修的实例。  相似文献   
8.
主要探讨了选择虚拟现实系统,建立虚拟现实环境以及虚拟现实系统在实际应用,同时阐述了虚拟现实在未来室内设计的发展趋势。通过该系统让用户仿佛置身于这个设计的虚拟场景中,感受身临其境的效果。  相似文献   
9.
介绍了虚拟现实技术的国内外研究现状,以及仿真技术与虚拟现实技术结合使用的发展趋势.为了更好地履行反恐使命,适应形势的发展,有必要提高反恐教学训练质量,创新反恐行动教学训练手段.将仿真技术和虚拟现实技术应用于路边炸弹的虚拟及仿真,能使反恐受训者不受时间、空间、经费和器材的限制,利用各种3D虚拟模型任意组装不同起爆方式下的路边炸弹,拓展其想象空间和创新思维,使之对路边炸弹的结构组成、工作原理及爆炸效应等有深刻理解.  相似文献   
10.
The three-dimensional virtual scene can provide users with a visual three-dimensional virtual environment, with various multimedia channels such as sound, video, force feedback equipment, etc., to bring users a completely immersive interactive experience. This paper introduces 3D imaging and virtual reality technology in the film and television industry cloud exhibition, and develops a virtual display platform. First of all, this paper divides the registration into two processes: camera calibration and joint calibration of the camera and laser scanner based on the calibration results. Camera calibration can determine the plane model of the calibration board in the camera coordinate system, and the joint calibration uses the RANSAC algorithm to extract the point cloud of the plane model of the calibration board, and then optimizes the distance between the points in the plane model point cloud and the corresponding plane in the camera coordinate system Find the optimal transformation between the two sets of data, and then calculate the registration relationship between the point cloud and the image. Secondly, this article conducts a demand analysis of the film and television industry cloud exhibition platform based on virtual reality technology, including the business goals set by the platform, platform system analysis, overall design, and system operating environment and configuration requirements. This model provides a feasible solution for the visual interaction of the cloud exhibition design of the film and television industry.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号