时间：12月5日星期五上午10：00
地点：浙大紫金港校区CAD&CG国家重点实验室402室
报告人：袁铭辉　教授
主持人：高曙明　教授
报告题目：Boolean Operation using OFN Surfel-Mesh

Abstract：Boolean operation is a necessary operation in geometric modelling to create complex models. Inherently Boolean of mesh models creates substantial problems in geometric computation as it involves determination of intersection of mesh faces; evaluation and membership classification of the resulting geometric data, and handling of possible degeneracy issues. This makes the process tedious and time consuming. It is often difficult to guarantee geometry validity of the resulting geometric model.
Advancement in GPU parallel processing has providing opportunities to make significant improvements in Boolean operation computation, typically using techniques such as Layer Depth Image (LDI). The deficiency in this approach is the lack of topology information to support the final model creation.
Conventionally, surfel stands for surface elements. OFN surfels are surfels with embedded oriented-four-neighbourhood(OFN) topological information. An OFN Surfel-Mesh is composed of a set of OFN Surfels. A model represented by OFN Surfel-Mesh is guaranteed to be valid if each of the OFN surfels in the model satisfies the OFN connectivity and orientation requirements. The OFN Surfel-Mesh is inherently adapted to parallel computation and thus enabling fast Boolean operation. The embedded topology in OFN Surfel-Mesh facilitates effective surfel traverse and point classification in potential degeneracy evaluation.
OFN Surfel-Mesh can find applications in contouring and creating valid STL models for 3D printing applications.

Bio：Professor Matthew Yuen is currently Professor of Mechanical Engineering at The Hong Kong University of Science and Technology. He graduated from the University of Hong Kong with a 1st Class Honours in Mechanical Engineering and obtained his Ph.D. in Mechanical Engineering from Bristol University. He worked for GEC and Babcock & Wilcox in UK before returning to Hong Kong in 1979 to lecture at the University of Hong Kong.
He joined The Hong Kong University of Science and Technology (HKUST) as one of the founding members of the Department of Mechanical Engineering in 1992. He had served as the Associate Dean of Engineering, the founding Director of the CAD/CAM Facility and the founding Director of the EPACK Laboratory at HKUST. On top of his academic duties, in 1998-2007, he served as the Director of the Technology Transfer Center at HKUST and concurrently as the Vice President of the HKUST R&D Corporation. Between January 2009 and October 2010, Professor Yuen was the Acting Vice-President for Research and Development at HKUST. He was also the CEO and President of the HKUST R&D Corporation. Under his leadership, HKUST was the only University in Hong Kong to receive an extra 20% funding from The University Grants Council for Knowledge Transfer.  He was Head of Department of Mechanical Engineering at The Hong Kong University of Science and Technology starting from 2008 to June 2014.
He has successfully guided the Department to initiate a program in Aerospace Engineering and the name of the Department was changed to Department of Mechanical and Aerospace Engineering in 2013.
Professor Yuen’s research areas cover: computer-aided-design, computer-aided-manufacturing, electronic packaging, and medical devices. He has published more than 200 papers in international journals and conferences. He holds 5 US patents, 3 Chinese patents and has 9 US patents pending. He has won Best Paper Awards from the Institution of Mechanical Engineers, UK and American Society of Mechanical Engineers. He was a Commonwealth Fellow and a United Nation Industrial Development Organization Fellow.  He is a Fellow of the Institution of Mechanical Engineers (UK) and a Fellow of the Hong Kong Institution of Engineers. Professor Yuen teaches courses on engineering design and manufacture, technology innovation and intellectual property law.