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81.
The effectiveness of an active shutter-glasses stereoscopic display (SD) and a passive polarised SD was evaluated in a live robot-teleoperation task and a simulated indirect-vision driving task in various terrains. Overall, participants completed their tasks significantly faster with the SDs in three-dimensional (3D) mode than with the SDs in the baseline 2D mode. They also navigated more accurately with the SDs in 3D mode. When the effectiveness of the two types of SDs was examined separately, results showed that the active shutter-glasses SD resulted in faster responses and task completion times than the passive polarised SD, though most of the differences failed to reach statistical significance. Perceived workload when interacting with the two SD systems did not differ significantly between the active versus passive display types or between the 3D and 2D modes of operation; however, participants reported more severe discomfort after interacting with the passive polarised SD.  相似文献   
82.
This study aims to determine whether indirect touch device can be used to interact with graphical objects displayed on another screen in an air traffic control (ATC) context. The introduction of such a device likely requires an adaptation of the sensory-motor system. The operator has to simultaneously perform movements on the horizontal plane while assessing them on the vertical plane. Thirty-six right-handed participants performed movement training with either constant or variable practice and with or without visual feedback of the displacement of their actions. Participants then performed a test phase without visual feedback. Performance improved in both practice conditions, but accuracy was higher with visual feedback. During the test phase, movement time was longer for those who had practiced with feedback, suggesting an element of dependency. However, this ‘cost’ of feedback did not extend to movement accuracy. Finally, participants who had received variable training performed better in the test phase, but accuracy was still unsatisfactory. We conclude that continuous visual feedback on the stylus position is necessary if tablets are to be introduced in ATC.  相似文献   
83.
This pilot study focuses on the use real‐time visual feedback technology (VFT) in vocal training. The empirical research has two aims: to ascertain the effectiveness of the real‐time visual feedback software ‘Sing & See’ in the vocal training of pre‐service music teachers and the teachers' perspective on their experience with VFT. Forty participants from an undergraduate music teacher education programme were randomly assigned to three groups. The first two groups were assigned the teacher and student versions of Sing & See, respectively, and the third group served as a control group without access to the software. The experimental groups were given 12 weeks to use the software for vocal training on a self‐regulated basis. The technique of complex selections (TCS) was designed to assess the pitch accuracy and richness of vocal timbre. Pre‐ and post‐test singing tasks showed that the participants from the experimental groups significantly improved their vocal timbre. A questionnaire survey conducted after the training period found that most of the participants in the experimental s were positive about the effectiveness of VFT software in vocal training. As future leaders in the implementation of music education technology, pre‐service music teachers expressed a positive attitude towards the use of VFT as a technology‐enhanced learning (TEL) component in music education.  相似文献   
84.
We present a visual analytics system to understand the operation data of a company, GAStech, from IEEE VAST Challenge 2016. The data include proximity data recording the locations and movements of employees, and heating, ventilation, and air conditioning (HVAC) data recording the environmental conditions in the building. Analyzing the data to detect the suspicious behaviors of some disgruntled employees is of special interest. Our system provides coordinated multiple views to visualize the proximity data and the HVAC data over time. Visual hints and comparisons are designed for users to identify abnormal patterns and compare them. Furthermore, the system automatically detects and correlates the anomalies in the data. We provide use cases to demonstrate the effectiveness of our system.  相似文献   
85.
通过云浮硫铁矿计算机动态管理系统的开发,总结出一般矿山企业物资计算机管理系统在开发过程中应注意的问题,为其它矿山企业物资计算机动态管理系统的开发提供了有益的经验。  相似文献   
86.
This paper presents a dynamic compensation concept to grapple with the dynamic defects of a traditional robot arm, especially while performing high-speed endpoint regulations. The proposed high-speed dynamic compensation concept offers a new point of view for cooperating with a traditional manipulator to realize highly dexterous performance of manipulations. The concept is realized through adoption of a high-speed light-weight actuator as well as endpoint closed loop configured high-speed cameras. The dynamic compensation is analyzed experimentally with 1000 Hz visual feedback and a high-speed finger for a robot arm in the case of one degree of freedom. The advantage of the proposed approach is that the modeling for the robot system’s dynamics is not needed, whereas it is necessary and trivial in order to realize high-speed regulations by traditional approaches. Thus, the control issue becomes easier with the proposed approach. As an application for this concept, fast peg-and-hole alignment with large position and attitude uncertainty is studied. The alignment algorithm is based on a visual compliance strategy. Alignment experiments show that with the proposed concept of dynamic compensation as well as visual compliant motion control, robust and fast convergence was realized for most cases.  相似文献   
87.
对于工业企业而言,了解复烤片烟的颜色有利于指导烟叶储存养护等技术工作的开展。为了解决在复烤片烟环节颜色区分的局限,使烟叶颜色外观质量分析评价更为科学、准确,通过计算机图像获取技术,采用CIE1976L~*a~*b~*均匀色空间系统,并对数据进行PCA分析。结果表明:与传统物理或化学判断方法比较,该方法能有效地对河南、吉林、四川3个产区的正面、背面、混合面进行颜色区分,是一种可靠的复烤片烟质量评价辅助手段。  相似文献   
88.
比较了4种评价PVC-U塑化度的方法:目测法简单;溶剂法迅速,容易操作;拉伸法可定量判断,但需要大量样品;DSC法准确、方便。  相似文献   
89.
提出了一种无理数字典码的测试数据压缩方案,能有效地压缩芯片测试数据。方案利用无理数序列建立字典,编码时只需进行相容性检查,无需填充无关位,简化了操作步骤;同时,选择局部压缩率最大的一组数据作为最终编码结果,保证压缩效果可以达到局部最优。对ISCAS 89标准电路Mintest集的实验结果显示,该方案的压缩效果优于传统压缩方法,如Golomb码、FDR码、混合定变长码等。  相似文献   
90.
近年来,随着信号的稀疏性理论越来越受到人们的关注,稀疏表征分类器也作为一种新型的分类算法被应用到话者识别系统中。该模型的基本思想是:只要超完备字典足够大,任意待测样本都能够用超完备字典进行线性表示。基于信号的稀疏性理论,未知话者的向量系数,即稀疏解可以通过L1范数最小化获取。超完备字典则可视为语音特征向量在高斯混合模型-通用背景模型(GMM-UBM)上进行MAP自适应而得到的大型数据库。采用稀疏表征模型作为话者辨认的分类方法,基于TIMIT语料库的实验结果表明,所采用的话者辨认方法,能够大大提高说话人识别系统的性能。  相似文献   
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