博士 数学科学伊人直播 , 1992
伊人直播
学士 数学科学伊人直播 , 1988
伊人直播
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.
数字生态指数是伊人直播 大数据分析与应用技术国家工程实验室联合校内外多方共同开展的研究项目,将为数字中国建设提供科学评估工具,也为促进地方数字经济发展、营造良好数字生态环境提供实践抓手。
在张平文院士的领衔指导下,基于中国科伊人直播 学部工作局院士课题、发改委重大研究系列课题、网信办委托课题等研究基础,实验室于2020年开始连续四年发布《数字生态指数报告》。
相关学术研究成果在《电子政务》特约专刊发表,在政届、学界和业界都产生了较高影响力。
围绕“生态视角引领规制建设激发数据活力”的主题分享了观点,认为数字生态包括数字基础、数字能力、数字应用和数字规则四个一级指标。在数字生态视角之下,能够更好地建立数字规制、激发要素活力,实现理论与实践的相互促进,从而加快推动数据要素市场的建设和发展。首先介绍数字经济发展的时代背景以及国家的相关政策,接下来阐述激活数据要素价值过程中所需经历的数据要素化、价值化、资产化等重要步骤,最后就其中的规划、人才、场景、合规、协作等问题给出建议,探索通过流通交易、协同赋能、多源融合等模式来进一步激活数据要素价值,促进经济高质量发展。
围绕“生态视角引领规制建设激发数据活力”的主题分享了观点,认为数字生态包括数字基础、数字能力、数字应用和数字规则四个一级指标。在数字生态视角之下,能够更好地建立数字规制、激发要素活力,实现理论与实践的相互促进,从而加快推动数据要素市场的建设和发展。
首先通过若干理论探讨和客观现象来阐述数字经济的重要性,然后对数字经济领域中的几个重要问题,即数据生产要素特征、数字化转型规律、以及数字经济如何评估等进行深入分析,并强调构建数字生态的重要性,最后对伊人直播 在数字经济和数字生态方面已经开展的一些工作做简要介绍。
首先对武汉大学学科建设的目标、特色、理念,观念等方面进行梳理,然后结合武汉大学2023年“学科建设年”具体行动,从人才培养、队伍建设、科学研究、体制机制改革等四个方面重点介绍武汉大学优化学科布局,探索学科交叉研究和交叉学科发展模式等一系列加强学科建设的举措和成效,最后强调,学科发展要以党建引领、资源配置协同、治理体系完善、大学精神凝心铸魂为实践保障。
从应用数学的价值观与发展历史说起,阐述什么是机理与数据的融合计算及其特点和意义,然后通过智慧气象预报与AI for Social Science两个方面来介绍如何有效地结合具体场景来应用机理与数据的融合计算,最后分析了融合计算对应用数学的影响,并探讨如何加强相关体制机制的建设来促进机理与数据融合计算的发展。
首先简要介绍数字化时代对人类、社会和国家的影响以及目前北大在数字化方面的理论探索进展,然后详细阐述伊人直播 在数智化建设方面所取得的成果,之后对教育数智化进行思考,探索教育与数智化的关系、数智化对教育的影响以及教育应该对数智化发展所起的引导作用,最后对教育数智化的未来发展提出了若干建议。
本报告首先从几个日常问题切入,揭示“计算在当前已经与生产生活密不可分”的结论,进而简要介绍数学和计算相互交融的历史进程和发展现状,接下来详细阐述计算的几个要素(数据、算法、算力和场景)所具有的特点、新的时代特征和数学在其中的重要作用等,最后对计算与数学共进的未来进行展望。
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 - 《工程数学学报》
2006 - 《数学杂志》
2004 - 《计算数学》
2004 - 《计算物理》
2004 - 《东北数学》
李英女士