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971.
为了解决当前地铁屏蔽门人群挤压荷载测试装置存在的自动化程度不高、产生的线荷载不精确不均匀的问题,综合计算机软件技术、自动控制技术和传感器技术设计了地铁屏蔽门人群挤压荷载测试系统.设计了计算机软件和PLC控制程序实现测试过程的自动控制.采用多点加载法,并对加载点引入闭环反馈控制来实现对荷载的精确控制.实验结果证明,设计的系统实现了测试的自动化,并解决了线荷载不精确不均匀的问题. 相似文献
972.
973.
Inspired by recent work on robust and fast computation of 3D Local Reference Frames (LRFs), we propose a novel pipeline for coarse registration of 3D point clouds. Key to the method are: (i) the observation that any two corresponding points endowed with an LRF provide a hypothesis on the rigid motion between two views, (ii) the intuition that feature points can be matched based solely on cues directly derived from the computation of the LRF, (iii) a feature detection approach relying on a saliency criterion which captures the ability to establish an LRF repeatably. Unlike related work in literature, we also propose a comprehensive experimental evaluation based on diverse kinds of data (such as those acquired by laser scanners, Kinect and stereo cameras) as well as on quantitative comparison with respect to other methods. We also address the issue of setting the many parameters that characterize coarse registration pipelines fairly and realistically. The experimental evaluation vouches that our method can handle effectively data acquired by different sensors and is remarkably fast. 相似文献
974.
阿法狗围棋系统的简要分析 总被引:1,自引:0,他引:1
谷歌的围棋系统阿法狗(AlphaGo)在三月的比赛中以4:1的成绩击败了围棋世界冠军李世石, 大大超过了许多人对计算机围棋程序何时能赶上人类职业高手的预期(约10~30年).本文在技术层面分析了阿法狗系统的组成部分, 并基于它过去的公开对局预测了它可能的弱点. 相似文献
975.
This paper develops and tests a motivational model to explain the overall continuance intention to use computers and smartphones. Based on survey data from 192 undergraduate students, structural equation modeling analysis is used to report: (1) the independent effect of intrinsic motivation on the continuance intention to use computers and smartphones; (2) the independent effect of extrinsic motivation on the continuance intention to use computers but not smartphones; (3) intrinsic motivation mediating the effect of extrinsic motivation on the continuance intention to use computers; (4) the independent effect of technology cognizance on the continuance intention to use computers but not smartphones; (5) intrinsic motivation positively influencing extrinsic motivation and technology cognizance, with respect to both devices. This research contributes to an improved understanding of the independent and interrelated effects of intrinsic and extrinsic motivations to use technological devices. The findings have important implications for theory and practice regarding the overall use of technology. 相似文献
976.
A cross‐cultural study of the effect of a graph‐oriented computer‐assisted project‐based learning environment on middle school students' science knowledge and argumentation skills 下载免费PDF全文
The purpose of this mixed‐methods study was to explore how seventh graders in a suburban school in the United States and sixth graders in an urban school in Taiwan developed argumentation skills and science knowledge in a project‐based learning environment that incorporated a graph‐oriented, computer‐assisted application (GOCAA). A total of 42 students comprised the treatment condition and were engaged in a project‐based learning environment that incorporated a GOCAA. Of these 42 students, 21 were located in the United States and 21 were located in Taiwan. A total of 26 students comprised the control condition and were engaged in a project‐based learning environment without the GOCAA. Of these 26 students, 15 were in the United States and 11 were in Taiwan. In each country, verbal collaborative argumentation was recorded and the students' post‐essays were collected. A one‐way analysis of variance (ANOVA) was conducted for each measure of science knowledge about alternative energies. The results showed a significant treatment effect for the outcome of scientific explanation among U.S. students, while among Taiwanese students, a significant treatment effect on scientific facts was observed. A one‐way ANOVA was additionally conducted for each measure of argumentation skills and a significant treatment effect on counterarguments and rebuttals was observed among the U.S. students, while in Taiwan, a significant treatment effect on reasoning and rebuttals was observed. A qualitative analysis was conducted to examine how the GOCAA supported students' development of argumentation skills in different countries. This study found distinct argumentation patterns between the U.S. and Taiwanese intervention teams. Additionally, a distinct gender difference in the use of evidence and division of labour was noted when the Taiwanese teams were compared with the U.S. teams, which may be explained by cultural differences. This study concluded that, in both the United States and Taiwan, a project‐based learning environment incorporating a GOCAA was effective in improving students' science knowledge and developing their scientific argumentation skills. 相似文献
977.
978.
Kailas Vodrahalli Achintya K. Bhowmik 《Journal of the Society for Information Display》2017,25(11):676-694
Recent advances in the field of computer vision can be attributed to the emergence of deep learning techniques, in particular convolutional neural networks. Neural networks, partially inspired by the brain's visual cortex, enable a computer to “learn” the most important features of the images it is shown in relation to a specific, specified task. Given sufficient data and time, (deep) convolutional neural networks offer more easily designed, more generalizable, and significantly more accurate end‐to‐end systems than is possible with previously employed computer vision techniques. This review paper seeks to provide an overview of deep learning in the field of computer vision with an emphasis on recent progress in tasks involving 3D visual data. Through a backdrop of the mammalian visual processing system, we hope to also provide inspiration for future advances in automated visual processing. 相似文献
979.
传统无人机飞控计算机检测以人工操作为主,操作繁琐、数据量大、易受人为因素影响,导致测试效率低、结果主观性强、安全性不足;提出基于信号门限自动检测技术的飞控计算机一键式全功能检测方案;以586-Driver板卡为核心,设计了接口板、电源板、信号调理板和检测板,研制了智能检测系统;模块功能包括底层驱动、时序控制、上电控制与电流检测、功能检测等模块,实现了在全程无人干预情况下对飞控计算机按预设时序逻辑的自动测试;采用人为注入故障测试方式进行了系统测试,结果表明:该系统满足某型飞控计算机的检测需求,提高了飞控计算机检测效率,具有实际工程应用价值。 相似文献
980.
张识达 《计算机测量与控制》2017,25(3):126-129
为实现当前经济市场中各应用软件的整合,提高我国各行业间个性化软件的开发能力,加强企业间的科学化系统软件设立,保证企业的高效运行,以及质量和系统维护能力;根据较为常用的分布式计算机系统,提出一种软件数据整合平台的设计;以商用软件整合平台设计为例,以开发模式、服务、技术结构、功能为研究方向,在企业正常运行时,可以实现业务系统功能开发以及门户单点登录,提高企业的个性化系统应用和经济效益;本文根据以上基本需求提出该功能软件平台进行设计,并在实际应用中分析出对于当前企业发展所提供的助力;结果显示,在当前经济发展状况下,有效地使用软件数据整合平台可以很大程度上提高企业的科学化管理和有效的资源分配,使企业在市场竞争中提高经济效益和社会效益。 相似文献