学术报告
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On the Value Distribution Theory of Algebroid FunctionsIn this lecture, we will introduce the basic definitions and summarize some main results on the value distribution theory of algebroid functions. The results focus on the singular directions, filling discs, uniqueness theorems. These results are compared with the case of meromorphic functions. Some open problems are also proposed.玄祖兴 教授 (北京联合大学)腾讯会议室2020年10月25日 (周日) 14:00-15:00
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Long-Time Behaviors of Numerical Methods on Random Genetic DriftRandom genetic drift occurs at a single unlinked locus with two or more alleles. The probability density of alleles is governed by a degenerated Fokker-Planck equation. Due to the degeneration and convection, Dirac singularities will always be developed at boundary as time evolves, which is just the so-called fixation phenomenon. In order to find a complete solution which should keep the conservation of positivity, total probability and expectation, different schemes of FDM, FVM and FEM are tested to solve the equation numerically. We observed that the methods have totally different long-time behaviors. Some of them are stable and keep the conservation of positivity and probability, but fail to keep the expectation. Some of them fails to keep the positivity.岳兴业 教授(苏州大学)腾讯会议室2020年10月23日(周五)下午 15:30-16:30
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Revisit Heterogeneous Multiscale MethodsIn this talk, we will revisit the Heterogeneous Multiscale Methods(HMM) for homogenization of elliptic problems. Firstly we talk about the relationship between HMM and other multiscale methods such as Variational Multiscale Methods, Multiscale Finite Element Methods and Free Bubble Methods. Then we discuss the error analysis for problems without scale separation.岳兴业 教授(苏州大学)腾讯会议室2020年10月23日(周五)下午 14:30-15:30
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Efficient Estimation and Computation of Parameters and Nonparametric Function...The efficiency of estimation for the parameters in semiparametric models has been widely studied in the literature. In this paper, we study efficient estimators for both parameters and nonparametric functions in a class of generalized semi/non-parametric regression models, which cover commonly used semiparametric models such as partially linear models, partially linear single index models, and two-sample semiparametric models. We propose a maximum likelihood principle combined with the local linear technique for estimating the parameters and nonparametric functions. The proposed estimators of the parameters and a linear functional of the nonparametric functions are consistent and asymptotically normal and are further shown to be semiparametrically efficient.林华珍 教授(西南财经大学)腾讯会议室2020年10月21日(周三)晚20:00开始
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Horo-Convex Hypersurfaces with Prescribed Shifted Gauss Curvatures in Hyperbo...In this paper, we consider prescribed shifted Gauss curvature equations for horo-convex hypersurfaces in hyperbolic space. Under some sufficient conditions, we obtain an existence result by the standard degree theory based on a priori estimates for solutions to the equations. Different from the prescribed Weingarten curvature problem in space forms, we do not impose a condition for radial derivative of the functions in the right hand side of the equations to prove the existence due to the horo-convexity of hypersurfaces in hyperbolic space.陈立 博士(湖北大学)腾讯会议室2020年10月15日 14:00-16:00
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A Grassmannian Loomis-Whitney Inequality and its DualBased on reverse isoperimetric inequalities on Grassmann manifolds, a Grassmannian Loomis-Whitney inequality and its dual are established, which provides a lower bound for the volume of an origin-symmetric convex body in terms of its lower dimensional sections.李爱军 教授( 河南理工大学)腾讯会议室2020年10月13日 09:00-10:00
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New Sine Ellipsoids and Related Volume InequalitiesThe celebrated Legendre ellipsoid and the LYZ ellipsoid introduced by Lutwak, Yang, and Zhang in 2000 are important concepts in convex geometric analysis. These ellipsoids are generated by the cosine transform (i.e., this transform origins from the inner product of two vectors). In this talk, we will discuss two types of ellipsoids by using the sine transform (i.e., this transform is related to the cross product of two vectors), which can be considered as the sine counterparts of the Legendre ellipsoid and the LYZ ellipsoid.黄卿中 博士(加拿大纽芬兰纪念大学)腾讯会议室2020年10月13日 8:00-9:00
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The Gradient Flow of Isoperimetric Ratio for Immersed Locally Convex Closed C...In this talk, we investigate the evolution of a curvature flow in the plane, which can be regarded as the gradient flow of isoperimetric ratio, for immersed locally convex closed curves. In particular, it is shown that the flow evolves two classes of rotationally symmetric curves, i.e., highly symmetric curves and Abresch-Langer type curves, into $m$fold circles as time goes to infinity.王小六 副教授 (东南大学)腾讯会议室2020年10月13日 10:00-11:00