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121.
Forrest W. Young David J. Lubinsky 《Journal of computational and graphical statistics》2013,22(4):229-250
Abstract The concept of statistical strategy is introduced and used to develop a structured graphical user interface for guiding data analysis. The interface visually represents statistical strategies that are designed by expert data analysts to guide novices. The representation is an abstraction of the expert's concepts of the essence of a data analysis. We argue that an environment that visually guides and structures data analysis will improve data analysis productivity, accuracy, accessibility, and satisfaction in comparison to an environment without such aids, especially for novice data analysts. Our concepts are based on notions from cognitive science, and can be empirically evaluated. The interface consists of two interacting windows—the guidemap and the workmap. Each window contains a graph that has nodes and edges. The guidemap graph represents the statistical strategy for a specific statistical task (such as describing data). Nodes represent potential data analysis actions that can be taken by the system. Edges represent potential actions that can be taken by the analyst. The guidemap graph exists prior to the data analysis session, having been created by an expert. The workmap graph represents the complete history of all steps taken by the data analyst. It is constructed during the data analysis session as a result of the analyst's actions. Workmap nodes represent data sets, data models, or data analysis procedures that have been created or used by the analyst. Workmap edges represent the chronological sequence of the analyst's actions. One workmap node is highlighted to indicate which statistical object is the focus of the strategy. We illustrate our concepts with ViSta, the Visual Statistics system that we have developed. 相似文献
122.
Pedestrians’ road-crossing behavior can often interrupt traffic flow and cause vehicle queueing. In this paper, we propose some moving rules for modeling the interaction of vehicles and pedestrians. The modified visual angle car-following model is presented for the movement of vehicles with consideration of the lateral effect of waiting pedestrians. The pedestrians’ behavior is summarized as consisting of three steps: pedestrian arrival, gap acceptance, and pedestrian crossing. Some characteristic parameters of pedestrians are introduced to characterize pedestrians’ behavior. Simulation results show that the interaction of vehicles and pedestrians lowers the traffic capacity and increases delays to both vehicles and pedestrians. 相似文献
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125.
介绍了在标准钟罩检测装置的基础上增设传动装置、旋转编码器、计算机等部件组成系统,形成了可自动计量、检定的全自动钟罩式气体检定装置。计算机对PLC采集的所有的数据进行处理,对现场进行实时监控,自动计算分析检测数据,并自动打印出检定结果。该自动检定系统的实现,对于提高气体流量仪表检定的效率和准确度具有实际意义。 相似文献
126.
在传统的开放式考试平台的基础上,利用Visual C 6.0开发了一个视频监控系统,从而保证考试的严肃性、公平性和公正性. 相似文献
127.
Saliency model-based face segmentation and tracking in head-and-shoulder video sequences 总被引:1,自引:0,他引:1
Hongliang Li King N. Ngan 《Journal of Visual Communication and Image Representation》2008,19(5):320-333
In this paper, a novel face segmentation algorithm is proposed based on facial saliency map (FSM) for head-and-shoulder type video application. This method consists of three stages. The first stage is to generate the saliency map of input video image by our proposed facial attention model. In the second stage, a geometric model and an eye-map built from chrominance components are employed to localize the face region according to the saliency map. The third stage involves the adaptive boundary correction and the final face contour extraction. Based on the segmented result, an effective boundary saliency map (BSM) is then constructed, and applied for the tracking based segmentation of the successive frames. Experimental evaluation on test sequences shows that the proposed method is capable of segmenting the face area quite effectively. 相似文献
128.
网络的宽带化发展有效促进了可视化资源的使用,特别是"三网融合",推动了应用协作和资源共享的发展,在三网间共享资源,实现整个社会信息资源的重复利用和深度挖掘,必将给社会带来巨大的经济效益和社会效益.因此,探索在"三网"间进行可视化资源协同、信息共享是社会信息化发展的重要内容. 相似文献
129.
R. Alkofer C. S. Fischer R. Williams 《The European Physical Journal A - Hadrons and Nuclei》2008,38(1):53-60
The U
A(1) problem of QCD is inevitably tied to the infrared behaviour of quarks and gluons with its most visible effect being the
-mass. A dimensional argument of Kogut and Susskind showed that the mixing of the pseudoscalar flavour-singlet mesons with
gluons can provide a screening of the Goldstone pole in this channel if the full quark-quark interaction is strongly infrared
singular as ∼ 1/k
4 . We investigate this idea using previously obtained results for the Landau gauge ghost and gluon propagator, together with
recent determinations for the singular behaviour of the quark-gluon vertex. We find that, even with an infrared vanishing
gluon propagator, the singular structure of the quark-gluon vertex for certain kinematics is apposite for yielding a non-zero
screening mass. 相似文献
130.
Essential properties of halo nuclei can be described in terms of a few low-energy constants. For neutron halo nuclei, analytical
results can be found for wave functions and electromagnetic transition matrix elements in simple but well-adapted models.
These wave functions can be used to study nuclear reactions; an especially simple and instructive example is Coulomb excitation.
A systematic expansion in terms of small parameters can be given. We present scaling laws for excitation amplitudes and cross-sections.
The results can be used to analyze experiments like 11Be Coulomb excitation. They also serve as benchmark tests for more involved reaction theories. 相似文献