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91.
Smith P. Shah M. da Vitoria Lobo N. 《Intelligent Transportation Systems, IEEE Transactions on》2003,4(4):205-218
This paper presents a system for analyzing human driver visual attention. The system relies on estimation of global motion and color statistics to robustly track a person's head and facial features. The system is fully automatic, it can initialize automatically, and reinitialize when necessary. The system classifies rotation in all viewing directions, detects eye/mouth occlusion, detects eye blinking and eye closure, and recovers the three dimensional gaze of the eyes. In addition, the system is able to track both through occlusion due to eye blinking, and eye closure, large mouth movement, and also through occlusion due to rotation. Even when the face is fully occluded due to rotation, the system does not break down. Further the system is able to track through yawning, which is a large local mouth motion. Finally, results are presented, and future work on how this system can be used for more advanced driver visual attention monitoring is discussed. 相似文献
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93.
Partner Relationship Management (PRM) is an information strategy that employs a set of applications focused on directly impacting an enterprise and its business partners' sales and services. Web services employ a distributed computing architecture that consists of many different computers that communicate over the Internet to form one system. the communication standards and protocols used in Web services are universally accepted. These Web services can be requested by client applications: Web based, windows, or mobile devices. This article presents an overview of PRM and Web services, and discusses the potential for improving partner relationship processes through the use of Web services. 相似文献
94.
This paper presents an efficient image-based approach to navigate a scene based on only three wide-baseline uncalibrated images without the explicit use of a 3D model. After automatically recovering corresponding points between each pair of images, an accurate trifocal plane is extracted from the trifocal tensor of these three images. Next, based on a small number of feature marks using a friendly GUI, the correct dense disparity maps are obtained by using our trinocular-stereo algorithm. Employing the barycentric warping scheme with the computed disparity, we can generate an arbitrary novel view within a triangle spanned by three camera centers. Furthermore, after self-calibration of the cameras, 3D objects can be correctly augmented into the virtual environment synthesized by the tri-view morphing algorithm. Three applications of the tri-view morphing algorithm are demonstrated. The first one is 4D video synthesis, which can be used to fill in the gap between a few sparsely located video cameras to synthetically generate a video from a virtual moving camera. This synthetic camera can be used to view the dynamic scene from a novel view instead of the original static camera views. The second application is multiple view morphing, where we can seamlessly fly through the scene over a 2D space constructed by more than three cameras. The last one is dynamic scene synthesis using three still images, where several rigid objects may move in any orientation or direction. After segmenting three reference frames into several layers, the novel views in the dynamic scene can be generated by applying our algorithm. Finally, the experiments are presented to illustrate that a series of photo-realistic virtual views can be generated to fly through a virtual environment covered by several static cameras. 相似文献
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96.
Rahaman Md. Saifur Hasnine Shah Md. Marzuk Ahmed Tanvir Sultana Salma Bhuiyan Md. Abdul Quaiyum Manir Md. Serajum Ullah Nayeb Sen Sapan Kumar Hossain Md. Nazmul Hossain Md. Sahadat Dafader Nirmal Chandra 《Iranian Polymer Journal》2021,30(10):1101-1116
Iranian Polymer Journal - Hydrogels were produced from mixtures of polyvinyl alcohol (PVA), polyvinyl pyrrolidone (PVP), and acrylic acid (AAc) using γ-radiation at doses of 3, 7, and... 相似文献
97.
A simple and rapid non-chromatographic method was developed to determine methylmercury (MeHg) and inorganic mercury (iHg) levels in muscles tissues of 10 freshwater fish species. The MeHg and iHg were determined by cold vapour atomic absorption spectrometry after alkaline wet digestion of samples. The digested samples were reduced sequentially with stannous chloride and sodium tetrahydroborate for iHg and MeHg, respectively. Parameters such as carrier gas flow rate (argon), volume of oxidizing and potassium persulphate solutions were investigated in detail. The accuracy of the technique was evaluated by using certified reference material (DORM-2) and spiking the both Hg species in muscles tissue of a fish. The limits of detection were 0.117 and 0.133 μg kg−1 for MeHg and iHg, respectively. The concentrations of MeHg and iHg in muscles tissues of ten fish species were found in the range of (28.4–56.3) and (3.01–8.11) μg kg−1, respectively. 相似文献
98.
Lee Spencer Martin Jakobsen Sunay Shah Graham Cairns 《Journal of the Society for Information Display》2013,21(8):352-360
There has been a rapid increase in the resolution of small‐sized and medium‐sized displays. This study determines an upper discernible limit for display resolution. A range of resolutions varying from 254–1016 PPI were evaluated using simulated display by 49 subjects at 300 mm viewing distance. The results of the study conclusively show that users can discriminate between 339 and 508 PPI and in many cases between 508 and 1016 PPI. 相似文献
99.
在油井管特殊扣产品的加工过程中,拧接是一个重要工序,而拧接设备是否具有自动判定的功能,自动判定方法合适与否,都会对生产节奏和质量控制产生影响。本文介绍了一种自动判定的方法,通过对拐点的扭矩数值、圈数的判断,再加上一些防错手段,实现对特殊扣拧接曲线的自动判定。 相似文献
100.