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Recent progress and trends in predictive visual analytics

Frontiers of computer Science 2017年第2期11卷 192-207页

作者： Junhua LU Wei CHEN Yuxin MA Junming KE Zongzhuang LI Fan ZHANG Ross MACIEJEWSKI State Key Lab of Computer Aided Design and Computer Graphics Zhejiang University Hangzhou 310058 China College of Science Zhejiang University of Technology Hangzhou 310023 China College of Computer Science and Technology Zhejiang University of Technology Hangzhou 310023 China School of Computing Informatics and Decision Systems Engineering Arizona State University Tempe AZ 85287-8809 USA

A wide variety of predictive analytics techniques have been developed in statistics, machine learning and data mining; however, many of these algorithms take a black-box approach in which data is input and future predictions are output with no insight into what goes on during the process. Unfortunately, such a closed system approach often leaves little room for injecting domain expertise and can result in frustration from analysts when results seem snurious or confusing. In order to allow for more human-centric approaches, the visualization community has begun developing methods to enable users to incorporate expert knowledge into the pre- diction process at all stages, including data cleaning, feature selection, model building and model validation. This paper surveys current progress and trends in predictive visual ana- lytics, identifies the common framework in which predictive visual analytics systems operate, and develops a summariza- tion of the predictive analytics workfiow.

关键词： predictive visual analytics visualization visual analytics data mining predictive analysis

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Consistency maintenance for constraint in role-based access control model

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Journal of Zhejiang University-SCIENCE A 2017年第3期3卷 292-297页

作者： Han, Wei-li Chen, Gang Yin, Jian-wei Dong, Jin-xiang State Key Laboratory of Computer Aided Design and Computer Graphics Zhejiang University Hangzhou China

Constraint is an important aspect of role-based access control and is sometimes argued to be the principal motivation for role-based access control (RBAC). But so far few authors have discussed consistency maintenance for constraint in RBAC model. Based on researches of constraints among roles and types of inconsistency among constraints, this paper introduces corresponding formal rules, rule-based reasoning and corresponding methods to detect, avoid and resolve these inconsistencies. Finally, the paper introduces briefly the application of consistency maintenance in ZD-PDM, an enterprise-oriented product data management (FDM) system.

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View-Aware Image Object Compositing and Synthesis from Multiple Sources

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Journal of computer Science & Technology 2016年第3期31卷 463-478页

作者： Xiang Chen Wei-Wei Xu Sai-Kit Yeung Kun Zhou State Key Laboratory of Computer Aided Design and Computer Graphics Zhejiang University Hangzhou 310058 China Vision Graphics and Computational Design Group Singapore University of Technology and Design Singapore 487372 Singapore

Image compositing is widely used to combine visual elements from separate source images into a single image. Although recent image compositing techniques are capable of achieving smooth blending of the visual elements from different sources, most of them implicitly assume the source images are taken in the same viewpoint. In this paper, we present an approach to compositing novel image objects from multiple source images which have different viewpoints. Our key idea is to construct 3D proxies for meaningful components of the source image objects, and use these 3D component proxies to warp and seamlessly merge components together in the same viewpoint. To realize this idea, we introduce a coordinate- frame based single-view camera calibration algorithm to handle general types of image objects, a structure-aware cuboid optimization algorithm to get the cuboid proxies for image object components with correct structure relationship, and finally a 3D-proxy transformation guided image warping algorithm to stitch object components. We further describe a novel application based on this compositing approach to automatically synthesize a large number of image objects from a set of exemplars. Experimental results show that our compositing approach can be applied to a variety of image objects, such as chairs, cups, lamps, and robots, and the synthesis application can create novel image objects with significant shape and style variations from a small set of exemplars.

关键词： image cloning 3D proxy probabilistic modeling data-driven method

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Variance Analysis and Adaptive Sampling for Indirect Light Path Reuse

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Journal of computer Science & Technology 2016年第3期31卷 547-560页

作者： Hao Qin Xin Sun Jun Yan Qi-Ming Hou Zhong Ren Kun Zhou State Key Laboratory of Computer Aided Design and Computer Graphics Zhejiang University Hangzhou 310058 China Microsoft Research Asia Beijing 100080 China

In this paper, we study the estimation variance of a set of global illumination algorithms based on indirect light path reuse. These algorithms usually contain two passes -- in the first pass, a small number of indirect light samples are generated and evaluated, and they are then reused by a large number of reconstruction samples in the second pass. Our analysis shows that the covariance of the reconstruction samples dominates the estimation variance under high reconstruction rates and increasing the reconstruction rate cannot effectively reduce the covariance. We also find that the covariance represents to what degree the indirect light samples are reused during reconstruction. This analysis motivates us to design a heuristic approximating the covariance as well as an adaptive sampling scheme based on this heuristic to reduce the rendering variance. We validate our analysis and adaptive sampling scheme in the indirect light field reconstruction algorithm and the axis-aligned filtering algorithm for indirect lighting. Experiments are in accordance with our analysis and show that rendering artifacts can be greatly reduced at a similar computational cost.

关键词： Monte Carlo method global illumination variance indirect light path reuse

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A Survey of Visual Analytic Pipelines

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Journal of computer Science & Technology 2016年第4期31卷 787-804页

作者： Xu-Meng Wang Tian-Ye Zhang Yu-Xin Ma Jing Xia Wei Chen State Key Laboratory of Computer Aided Design and Computer Graphics Zhejiang University Hangzhou 310058 China Innovation Joint Research Center for Cyber-Physical-Society System Zhejiang University Hangzhou 310058 China

Visual analytics has been widely studied in the past decade. One key to make visual analytics practical for both research and industrial applications is the appropriate definition and implementation of the visual analytics pipeline which provides effective abstractions for designing and implementing visual analytics systems. In this paper we review the previous work on visual analytics pipelines and individual modules from multiple perspectives： data, visualization, model and knowledge. In each module we discuss various representations and descriptions of pipelines inside the module, and compare the commonalities and the differences among them.

关键词： visual analytics pipeline visualization model knowledge

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Quantification of flupirtine maleate polymorphs using X-ray powder diffraction

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Chinese Chemical Letters 2016年第11期27卷 1666-1672页

作者： Yu-Mei Zhao Zhi-Bing Zheng Song Li Laboratory of Computer-Aided Drug Design & Discovery Beijing Institute of Pharmacology and Toxicology Laboratory of Structure Identification Beijing Institute of Pharmacology and Toxicology State Key Laboratory of Toxicology and Medical Countermeasures Beijing Institute of Pharmacology and Toxicology

Flupirtine maleate, a pharmaceutical compound for treating psychotic disease in clinics, has seven polymorphs. Form A, with better crystal stability and bioavailability, has been widely used as the pharmaceutical crystal form. Unfortunately, it is usually found in a polymorphic mixture with form B. In this study, pure crystal forms of A and B were prepared and characterized by X-ray powder diffraction （XRPD）, Fourier transform infrared spectroscopy （FT-IR） and thermal analysis. An XRPD-based method for the quantitative determination of the amount of the flupirtine maleate polymorphs form A and form B was also established through a systematic optimization of instrumental parameters. The results of the analytical methodology validation showed that the XPRD method had a broad quantitative range of 0- 100% （w/w）, good linear relationship, with R2= 0.999, excellent repeatability and precision and low limits of detection （LoD） of 0.15% （w/w） and quantification （LoQ） of 0.5% （w/w）. The results also showed that the single-peak method was not as good as the whole pattern in reducing the influence of the preferred orientation, but this can be compensated for by a systematic optimization of instrumental parameters and validating the analytical methodology to reduce errors and obtain a good, repeatable, sensitive, and accurate method. This XRPD method can be used to analyze mixtures of flupirtine maleate polymorphs （forms A and B） quantitatively and control the quality of the bulk drug.

关键词： Flupirtine maleate X-ray powder diffraction Quantitative analysis of polymorphs Preferred orientation Transmission

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Irradiance regression for efficient final gathering in global illumination

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Frontiers of computer Science 2015年第3期9卷 456-465页

作者： Xuezhen HUANG Xin SUN Zhong REN Xin TONG Baining GUO Kun ZHOU State Key Laboratory of Computer Aided Design and Computer Graphics Zhejiang University Hangzhou 310058 China Microsoft Research Asia Beijing 100029 China

Photon mapping is widely used for global illumi- nation rendering because of its high computational efficiency. But its efficiency is still limited, mainly by the intensive sam- piing required in final gathering, a process that is critical for removing low frequency artifacts of density estimation. In this paper, we propose a method to predict the final gather- ing estimation with direct density estimation, thereby achiev- ing high quality global illumination by photon mapping with high efficiency. We first sample the irradiance of a subset of shading points by both final gathering and direct radiance es- timation. Then we use the samples as a training set to predict the final gathered irradiance of other shading points through regression. Consequently, we are able to achieve about three times overall speedup compared with straightforward final gathering in global illumination computation with the same rendering quality.

关键词： global illumination photon mapping final gath-ering radiance estimation regression

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Publisher Correction: A new antagonist for CCR4 attenuates allergic lung inflammation in a mouse model of asthma

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Scientific reports 2018年第1期8卷 6859页

作者： Yang Zhang Yinfang Wu Hui Qi Junhai Xiao Hongwei Gong Yan Zhang Enquan Xu Song Li Dalong Ma Ying Wang Wen Li Huahao Shen Department of Immunology School of Basic Medical Sciences Key Laboratory of Immunology Ministry of Health Peking University Health Science Center Beijing 100191 China. Department of Hematology Peking University First Hospital Beijing 100034 China. Department of Respiratory Medicine the Second Affiliated Hospital School of Medicine of Zhejiang University Zhejiang University institute of Respiratory Diseases Hangzhou 310009 China. yw@***. Beijing Children's Hospital Capital Medical University Beijing 100045 China. Laboratory of Computer-Aided Drug Design & Discovery State Key Laboratory of Toxicology and Medical Countermeasures Beijing Institute of Pharmacology and Toxicology Beijing 100850 China. School of Pharmaceutical Sciences Jilin University Changchun 130021 China. Department of Respiratory Medicine the Second Affiliated Hospital School of Medicine of Zhejiang University Zhejiang University institute of Respiratory Diseases Hangzhou 310009 China. liwenzjhz0408@***. Department of Respiratory Medicine the Second Affiliated Hospital School of Medicine of Zhejiang University Zhejiang University institute of Respiratory Diseases Hangzhou 310009 China. hshen@***.

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.

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1-based construction of polycube maps from complex shapes

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ACM Transactions on graphics 2014年第3期33卷 1–11页

作者： Huang, Jin Jiang, Tengfei Shi, Zeyun Tong, Yiying Bao, Hujun Desbrun, Mathieu Key Lab of Computer-Aided Design and Computer Graphics Zhejiang University Hangzhou Zhejiang China Michigan State University East Lansing MI United States Caltech Pasadena CA United States

Polycube maps of triangle meshes have proved useful in a wide range of applications, including texture mapping and hexahedral mesh generation. However, constructing either fully automatically or with limited user control a low-distortion polycube from a detailed surface remains challenging in practice. We propose a variational method for deforming an input triangle mesh into a polycube shape through minimization of the 1-norm of the mesh normals, regularized via an as-rigid-as-possible volumetric distortion energy. Unlike previous work, our approach makes no assumption on the orientation, or on the presence of features in the input model. User-guided control over the resulting polycube map is also offered to increase design flexibility. We demonstrate the robustness, efficiency, and controllability of our method on a variety of examples, and explore applications in hexahedral remeshing and quadrangulation. © 2014 ACM.

关键词： Mesh generation

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44.2: An Analysis of Image Uniformity of Three-dimensional Image Based on Rotating LED Array Volumetric Display System

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SID Symposium Digest of Technical Papers 2012年第1期41卷

作者： Jiang Wu Caijie Yan Xinxing Xia Jia Hou Haifeng Li Xu Liu Wenting Zheng State Key Laboratory of Modern Optical Instrumentation Zhejiang University Hangzhou 310027 P.R. China State Key Laboratory of Computer Aided Design and Computer Graphics Zhejiang University Hangzhou 310058 P.R. China

We analyze the luminance uniformity and color uniformity of the color volumetric 3D display system based on a rotating LED screen. We first analyze the luminance and chromatic coordinate distribution for one RGB cube with different horizontal and vertical view angles and also luminance and color display effect for 64 spatial distributing RGB color cubes. To evaluate the luminance uniformity and color uniformity of 3D image with different display positions, we present three indexes for them respectively. for luminance uniformity, the indexes are the average luminance, the normalized luminance difference, and the average normalized luminance difference. And for color uniformity the indexes are the average of color difference, the maximum color difference, and the variance of color difference. By these evaluation parameters, we can compare luminance and color uniformity in different 3D volumetric display systems.

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