A NEW APPROACH ON IDENTIFICATION OF BOUNDARY PARAMETER FOR A TWODIMENSIONAL DIFFUSION SYSTEM

This paper presents a new approach of the boundary parameter identification of adiffusion system.The system model is governed by a two-dimensional parabolic problem,which involves an unknown boundary parameter.Identifiability of the boundary parameterand the new approach are discussed briefly,which show that the new approach can overcomenot only the ill-posedness of the nonlinear output least square method but also the difficultyof numerical computation of the nonlinear output least square estimate due to the existenceof the local minima of the performance functional,Finally,some numerical examples aregiven.     

悬臂弹性梁振动的稳定性

本文用宋健提出的具有结构阻尼的数学模型来研究悬臂梁弹性振动的稳定性。考虑简单情况:质量均匀,结构阻尼η是常数。设梁长为l,u(t,x)为梁上距x=0为x处的垂直于纵体轴的法向偏离,此时悬臂梁弹性振动方程为     

一类非线性动力学系统的稳定性分析

研究了具终身免疫的传染病动力系统,得出模型的稳态解的存在性,并且给出了此类非线性模型稳态解处局部渐近稳定的充分条件。