Title: | ICM Colloquium: The LLL Algorithm and Its Applications |
Speaker: | Prof. Sanzheng Qiao, Institute for Computational Mathematics, Hong Kong Baptist University, Hong Kong |
Time/Place: | 15:00 - 16:00 FSC1217, Fong Shu Chuen Library, HSH Campus, Hong Kong Baptist University |
Abstract: | The LLL algorithm, originated from Lenstra, Lenstra, Jr, and Lovasz, is a lattice basis reduction method. Wide applications ranging from cryptography to communications have been found since the publication of the original paper in 1982. In this talk, we first describe the original algorithm and a matrix interpretation of the algorithm and some properties in terms of matrix conditioning. Then we present a pivoting scheme and a proof of its convergence. Finally, possible future work is discussed. |
Title: | Regularity of Solutions for a Class of Kinetic Equations |
Speaker: | Prof. CHEN Hua, School Mathematics, Wuhan University, Cjoma |
Time/Place: | 11:30 - 12:30 FSC1217, Fong Shu Chuen Library, HSH Campus, Hong Kong Baptist University |
Abstract: | In this talk, we shall give some recent results on the regularity of solutions for a class of linear and nonlinear Kinetic equations, which are related to Boltzmann and Landau equations. Also we shall present some recent results on the optimal smoothness effect for the solutions of Cauchy problem for spatially homogeneous Landau equations. |
Title: | CMIV Colloquium: The Future of LCD TV: LED Backlight and Dynamic Backlight Control |
Speaker: | Dr. Min CHEN, ASTRI, Hong Kong |
Time/Place: | 11:30 - 12:30 DLB514, David C. Lam Building, Shaw Campus, Hong Kong Baptist University |
Abstract: | In the past dedicates, home TV have experienced two main evolutions. The first one is from black-white CRT to chromatic CRT. The second one is from CRT display to FPD (flat panel display). So far, home TV market is dominated by LCD display. Nowadays, LCD TV is facing to a new evolution. CCFL is replaced by LED and new backlight control modes are proposed to overcome the existing problems in current LCD displays: low dynamic range, low contrast, limited color depth and gamut, and high power consumption In this presentation, the core technologies of LED backlight and dynamic backlight control method developed by ASTRI will be introduced in detail. |
Title: | DLS: Higher Order Positive Semi-Definite Diffusion Tensor Imaging and Space Tensor Conic Programming |
Speaker: | Prof. Liqun Qi, Department of Applied Mathematics, The Hong Kong Polytechnic University, Hong Kong |
Time/Place: | 16:30 - 17:30 (Preceded by Reception at 4:00pm) RRS905, Sir Run Run Shaw Building, HSH Campus, Hong Kong Baptist University |
Abstract: | Due to the well-known limitations of diffusion tensor imaging (DTI), high angular resolution diffusion imaging (HARDI) is used to characterize non-Gaussian diffusion processes. One approach to analyze HARDI data is to model the apparent diffusion coefficient (ADC) with higher order diffusion tensors (HODT). The diffusivity function is positive semi-definite. In the literature, some methods have been proposed to preserve positive semi-definiteness of second order and fourth order diffusion tensors. None of them can work for arbitrary high order diffusion tensors. In this paper, we propose a comprehensive model to approximate the ADC profile by a positive semi-definite diffusion tensor of either second or higher order. We call this model PSDT (positive semi-definite diffusion tensor). PSDT is a convex optimization problem with a convex quadratic objective function constrained by the nonnegativity requirement on the smallest Z-eigenvalue of the diffusivity function. The smallest Z-eigenvalue is a computable measure of the extent of positive definiteness of the diffusivity function. We also propose some other invariants for the ADC profile analysis. Performance of PSDT is depicted on synthetic data as well as MRI data. PSDT can also be regarded as a conic linear programming (CLP) problem. Yinyu Ye and I investigated PSDT from the viewpoint of CLP. We characterize the dual cone of the positive semi-definite space tensor cone, and study the CLP formulation and duality of the positive semi-definite space tensor programming (STP) problem. |
Title: | Lecture Series on Graph Theory and Combinatorial Algorithms: Game Colouring of Graphs |
Speaker: | Prof. Xuding Zhu, National Sun Yat-sen University, Taiwan |
Time/Place: | 11:00 - 12:00 FSC1217, Fong Shu Chuen Library, HSH Campus, Hong Kong Baptist University |
Title: | Super-geometric Convergence of Spectral Collocation Methods for Eigenvalue Problems |
Speaker: | Prof. Zhimin Zhang, Department of Mathematics, Wayne State University, USA |
Time/Place: | 11:30 - 12:30 FSC1217, Fong Shu Chuen Library, HSH Campus, Hong Kong Baptist University |
Abstract: | Geometric or exponential convergence is one of the most remarkable features of the spectral method. Less well-known is the face that under some ideal situation, the convergence rate of the spectral method and the associated spectral collocation method may exceed the exponential rate. In this talk, we shall discuss such a super-geometric convergence phenomenon in the one-dimensional setting. Eigenvalue problems under concern include : the second order differential operator with jump coefficients and integral equations of the second kind. |
We organize conferences and workshops every year. Hope we can see you in future.
Learn MoreProf. M. Cheng, Dr. Y. S. Hon, Dr. K. F. Lam, Prof. L. Ling, Dr. T. Tong and Prof. L. Zhu have been awarded research grants by Hong Kong Research Grant Council (RGC) — congratulations!
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