Ph.D. in School of Mathematical Sciences, 1992
Peking University
B.S. in School of Mathematical Sciences, 1988
Peking University
Fine-grained weather forecasting data, i.e., the grid data with high-resolution, have attracted increasing attention in recent years, especially for some specific applications such as the Winter Olympic Games. Although European Centre for Medium-Range Weather Forecasts (ECMWF) provides grid prediction up to 240 hours, the coarse data are unable to meet high requirements of these major events. In this paper, we propose a method, called model residual machine learning (MRML), to generate grid prediction with high-resolution based on high-precision stations forecasting. MRML applies model output machine learning (MOML) for stations forecasting. Subsequently, MRML utilizes these forecasts to improve the quality of the grid data by fitting a machine learning (ML) model to the residuals. We demonstrate that MRML achieves high capability at diverse meteorological elements, specifically, temperature, relative humidity, and wind speed. In addition, MRML could be easily extended to other post-processing methods by invoking different techniques. In our experiments, MRML outperforms the traditional downscaling methods such as piecewise linear interpolation (PLI) on the testing data.
The nonlinear space-fractional problems often allow multiple stationary solutions, which can be much more complicated than the corresponding integer-order problems. In this paper, we systematically compute the solution landscapes of nonlinear constant/variable-order space-fractional problems on one- and two-dimensional rectangular domains. A fast approximation algorithm is developed to deal with the variable-order spectral fractional Laplacian by approximating the variable-indexing Fourier modes, and then combined with saddle dynamics to construct the solution landscape of variable-order space-fractional phase field model. Numerical experiments are performed to substantiate the accuracy and efficiency of fast approximation algorithm and elucidate essential features of the stationary solutions of space-fractional phase field model. Furthermore, we demonstrate that the solution landscapes of spectral fractional Laplacian problems can be reconfigured by varying the diffusion coefficients in the corresponding integer-order problems.
Liquid crystal is a typical kind of soft matter that is intermediate between crystalline solids and isotropic fluids. The study of liquid crystals has made tremendous progress over the last four decades, which is of great importance on both fundamental scientific researches and widespread applications in industry. In this paper, we review the mathematical models and their connections of liquid crystals, and survey the developments of numerical methods for finding the rich configurations of liquid crystals.
Due to structural incommensurability, the emergence of a quasicrystal from a crystalline phase represents a challenge to computational physics. Here, the nucleation of quasicrystals is investigated by using an efficient computational method applied to a Landau free-energy functional. Specifically, transition pathways connecting different local minima of the Lifshitz–Petrich model are obtained by using the high-index saddle dynamics. Saddle points on these paths are identified as the critical nuclei of the 6-fold crystals and 12-fold quasicrystals. The results reveal that phase transitions between the crystalline and quasicrystalline phases could follow two possible pathways, corresponding to a one-stage phase transition and a two-stage phase transition involving a metastable lamellar quasicrystalline state, respectively.
2020 - CSIAM Transactions on Applied Mathematics (Editor in Chief)
2014 - Multiscale Modeling & Simulation, A SIAM Interdisciplinary Journal
2013 - Science China Mathematics
2012 - Discrete and Continuous Dynamical System-B
2011 - Journal of Mathematics in Industry (Coordinating Editors)
2010 - Applied Mathematics and Mechanics;(Associate Chief Editor Since 2014)
2007 - Journal of Computational Mathematics
2006 - Communications in Computational Physics
2006 - International Journal of Nonlinear Science
2005 - Communication in Mathematical Sciences
2005 - Journal of Information and Computational Science
2005 - 2013 SIAM Journal on Numerical Analysis
2002 - Applied Mathematical Research Express (AMRX)
2010 - Advances in Mathematics
2007 - Journal of Engineering Mathematics (China)
2006 - Journal of Mathematics (China)
2004 - Journal of Computational Mathematics (China)
2004 - Journal of Computational Physics (China)
2004 - Northeast Mathematical Journal (China)
Ms. Ying Li