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First two cases of living related liver transplantation with complicated anatomy of blood vessels in Beijing

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World Journal of Gastroenterology 2004年第19期10卷 2854-2858页

作者： Wen-HanWu Yuan-LianWan LongLee yin-MoYang Yan-TingHuang Chao-LongChert sheung-TatFan DepartmentofSurgery TheFirstHospitalPekingUniversityBeijing100034China DepartmentofSurgery ChangGungMemorialHospital123Ta-PeiRoadNiao-SungKaohsiungTaiwanChina DepartmentofSurgery QueenMaryHospitalUniversityofHongKongMedicalCentre102PokfulamRoadHongKongChina

AIM: Living related liver transplantation (LRLT) has beendeveloped in response to the paediatric organ donor *** it has been succeeded in many centers worldwide,the safety of the donor is still a major concern, especiallyin donors with anatomy variation. We succeeded in performingthe first two cases of living related liver transplantationwith complicated anatomy of blood vessels as a way toovercome cadaveric organ shortage in ***: Two patients, with congenital liver fibrosis andcongenital biliary atresia were performed with living donorliver transplantation in our hospital and then followed upfrom November 12 to December 13, 2001. The two livingdonors, mother and father, were healthy aged 34 and 35years. One right lobe (segment V, VI, VII, VIII) and oneleft lateral lobe (segment II and III) were used. The graftsweighed 394 g and 300 g. The ratio of graft weight to thestandard liver volume (SLV) of donors was 68% and 27%.The graft weight to recipient body weight ratio was 3.2%and 4.4%. The graft weight to recipient estimated standardliver mass (ESLM) ratio was 63% and 85%. The two donorshad complicated blood vessel ***: Two patients undergone living donor livertransplantation had good results. Abnormal liver functionwith high bilirubin level appeared in a few days afteroperation, but liver function returned to normal one monthafter operation with bilirubin level almost decreased tonear normal. No bleeding, thrombosis, infection and bileleakage occurred. One had an acute rejection and *** two donors recovered in two weeks. One had slightfever because of a little collection in abdomen and recoveredafter paracentesis and drainage.

关键词：肝移植解剖学血管北京病例分析腹部疾病

Integrated phase unwrapping algorithm for the measurement of 3D shapes by Fourier transform profilometry

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第7期10卷 1018-1028页

作者： Shuang-qing WU yin ZHANG san-yuan ZHANG Xiu-zi YE School of Computer Science and Technology Zhejiang University Hangzhou 310027 China

An integrated and reliable phase unwrapping algorithm is proposed based on residues and blocking-lines detection, closed contour extraction and quality map ordering for the measurement of 3D shapes by Fourier-transform profilometry (FTP). The proposed algorithm first detects the residues on the wrapped phase image, applies wavelet analysis to generate the blocking-lines that can just connect the residues of opposite polarity, then carries out the morphology operation to extract the closed contour of the shape, and finally uses the modulation intensity information and the Laplacian of Gaussian operation of the wrapped phase image as the quality map. The unwrapping process is completed from a region of high reliability to that of low reliability and the blocking-lines can prevent the phase error propagation effectively. Furthermore, by using the extracted closed contour to exclude the invalid areas from the phase unwrapping process, the algorithm becomes more efficient. The experiment shows the effec-tiveness of the new algorithm.

关键词： Fourier-transform profilometry (FTP) Phase unwrapping Residues Blocking-lines Laplacian of Gaussian Modulation intensity

Flower solid modeling based on sketches

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第4期9卷 481-488页

作者： Zhan DING Shu-chang XU Xiu-zi YE yin ZHANG san-yuan ZHANG State Key Lab of CAD ＆ CG School of Computer Science Zhejiang University Hangzhou 310027 China

In this paper we propose a method to model flowers of solid shape. Based on (Ijiri et al., 2005)’s method, we separate individual flower modeling and inflorescence modeling procedures into structure and geometry modeling. We incorporate interactive editing gestures to allow the user to edit structure parameters freely onto structure diagram. Furthermore, we use free-hand sketching techniques to allow users to create and edit 3D geometrical elements freely and easily. The final step is to automatically merge all independent 3D geometrical elements into a single waterproof mesh. Our experiments show that this solid modeling approach is promising. Using our approach, novice users can create vivid flower models easily and freely. The generated flower model is waterproof. It can have applications in visualization, animation, gaming, and toys and decorations if printed out on 3D rapid prototyping devices.

关键词： Solid modeling Floral diagram Inflorescence Gesture Constrained Delauny triangulation (CDT) Freehand sketching

Image-based 3D model retrieval using manifold learning

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Frontiers of Information Technology & Electronic Engineering 2018年第11期19卷 1397-1408页

作者： Pan-pan MU san-yuan ZHANG yin ZHANG Xiu-zi YE Xiang PAN College of Computer Science and Technology Zhejiang University College of Mathematics and Information Science Wenzhou University College of Computer Science and Technology Zhejiang University of Technology

We propose a new framework for image-based three-dimensional(3D) model retrieval. We first model the query image as a Euclidean point. Then we model all projected views of a 3D model as a symmetric positive definite(SPD) matrix, which is a point on a Riemannian manifold. Thus, the image-based 3D model retrieval is reduced to a problem of Euclid-to-Riemann metric learning. To solve this heterogeneous matching problem, we map the Euclidean space and SPD Riemannian manifold to the same high-dimensional Hilbert space, thus shrinking the great gap between them. Finally, we design an optimization algorithm to learn a metric in this Hilbert space using a kernel trick. Any new image descriptors, such as the features from deep learning, can be easily embedded in our framework. Experimental results show the advantages of our approach over the state-of-the-art methods for image-based 3D model retrieval.

关键词： Model retrieval Euclidean space Riemannian manifold Hilbert space Metric learning

Adaptive foreground and shadow segmentation using hidden conditional random fields

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第4期8卷 586-592页

作者： CHU Yi-ping YE Xiu-zi QIAN Jiang ZHANG yin ZHANG san-yuan School of Computer Science State Key Lab. of CAD ＆ CG Zhejiang University Hangzhou 310027 China

Video object segmentation is important for video surveillance, object tracking, video object recognition and video editing. An adaptive video segmentation algorithm based on hidden conditional random fields (HCRFs) is proposed, which models spatio-temporal constraints of video sequence. In order to improve the segmentation quality, the weights of spatio-temporal con- straints are adaptively updated by on-line learning for HCRFs. Shadows are the factors affecting segmentation quality. To separate foreground objects from the shadows they cast, linear transform for Gaussian distribution of the background is adopted to model the shadow. The experimental results demonstrated that the error ratio of our algorithm is reduced by 23% and 19% respectively, compared with the Gaussian mixture model (GMM) and spatio-temporal Markov random fields (MRFs).

关键词： Video segmentation Shadow elimination Hidden conditional random fields (HCRFs) On-line learning

Trimming self-intersections in swept volume solid modeling

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第4期9卷 470-480页

作者： Zhi-qi XU Xiu-zi YE Zhi-yang CHEN yin ZHANG san-yuan ZHANG State Key Laboratory of CAD ＆ CG School of Computer Science and Technology Zhejiang University Hangzhou 310027 China College of Software Zhejiang University of Technology Hangzhou 310014 China

Swept volume solid modeling has been applied to many areas such as NC machining simulation and verification, robot workspace analysis, collision detection, and CAD. But self-intersections continue to be a challenging problem in the boundary representation of swept volume solids. A novel algorithm is presented in this paper to trim self-intersection regions in swept volume solids modeling. This trimming algorithm consists of two major steps: (1) roughly detecting self-intersection regions by checking intersections or overlapping of the envelop profiles; (2) splitting the whole envelop surfaces of the swept volume solid into separate non-self-intersecting patches to trim global self-intersections, and to trim local self-intersections, dividing local self-intersecting regions into patches and replacing self-intersecting patches with non-self-intersecting ones. Examples show that our algorithm is efficient and robust.

关键词： Self-intersection Swept volume (SV) Solid modeling

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第6期9卷 807-815页

作者： Ren-fang WANG Wen-zhi CHEN san-yuan ZHANG yin ZHANG Xiu-zi YE School of Computer Science and Technology Zhejiang University Hangzhou 310027 China Faculty of Computer Science and Information Technology Zhejiang Wanli University Ningbo 315100 China

A non-local denoising (NLD) algorithm for point-sampled surfaces (PSSs) is presented based on similarities, including geometry intensity and features of sample points. By using the trilateral filtering operator, the differential signal of each sample point is determined and called "geometry intensity". Based on covariance analysis, a regular grid of geometry intensity of a sample point is constructed, and the geometry-intensity similarity of two points is measured according to their grids. Based on mean shift clustering, the PSSs are clustered in terms of the local geometry-features similarity. The smoothed geometry intensity, i.e., offset distance, of the sample point is estimated according to the two similarities. Using the resulting intensity, the noise component from PSSs is finally removed by adjusting the position of each sample point along its own normal direction. Ex- perimental results demonstrate that the algorithm is robust and can produce a more accurate denoising result while having better feature preservation.

关键词： Point-sampled surfaces (PSSs) Similarity Geometry intensity Geometry feature Non-local filtering

Metal Spray Forming Process Examined Using Mathematical Model

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Journal of Iron and Steel Research International 2008年第2期15卷 46-50页

作者： ZHANG yin HE You-duo FAN Jun-fei REN san-bin School of Rare Earth Inner Mongolia University of Science and Technology Baotou 014010 Nei Monggol China Baoshan Iron and Steel Co Ltd Research Institute Shanghai 201900 China

The metal spray forming process was examined using the mathematical model simulation by Baosteel＇s test and developed *** mathematical model comprised of the probability and statistical analysis of the droplet mass b... 详细信息

关键词： spray forming droplet mathematical model billet

Mesh sharpening via normal filtering

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第4期10卷 546-553页

作者： Jian-guo SHEN san-yuan ZHANG Zhi-yang CHEN yin ZHANG Xiu-zi YE State Key Laboratory of CAD & CG Zhejiang University Hangzhou 310027 China Software College Zhejiang University of Technology Hangzhou 310014 China

We present a robust mesh sharpening approach to reconstructing sharp features from blended or chamfered features, even with noise and aliasing errors. Feature regions were first recognized via normal variation according to the user's input, and then normal filtering was applied to faces of feature regions. Finally, the vertices of the feature region were gradually updated based on new face normals using a least-squares error criterion. Experimental results demonstrate that the method is effective and robust in sharpening meshes.

关键词： Normal filtering Sharp feature Mesh sharpening Blend Chamfer