In this paper, some properties of the monotone set function defined by theChoquet integral are discussed. It is shown that several important structural characteristics of theoriginal set function, such as weak null-ad...In this paper, some properties of the monotone set function defined by theChoquet integral are discussed. It is shown that several important structural characteristics of theoriginal set function, such as weak null-additivity, strong order continuity, property (s) andpseudomelric generating property, etc., are preserved by the new set function. It is also shown thatC-integrability assumption is inevitable for the preservations of strong order continuous andpseudometric generating property.展开更多
The roughness of the model function f(x) to the basis functions has been identified. When the model function is continuous segment, its roughness does not depend on the behavior of the first segment, but depends on ...The roughness of the model function f(x) to the basis functions has been identified. When the model function is continuous segment, its roughness does not depend on the behavior of the first segment, but depends on "h", the shift in the slope of two consecutive segments. If the distribution of design is uniform, f(x) is continuous segment function, and h is constant, then the maximum roughness is h2/192 obtained at the midpoint of the observations. Suppose that we have a sequence of designs {Pn(x)} then its corresponding distribution {Fn (x)} converges weakly to some distribution F(x). Let D(f) be a set of discontinuous points off(x), it is possible to take the limit of the roughness if D(f) has zero (dF)-measure. The behavior of maximum roughness of the discontinuous segment function has been studied by using grid points.展开更多
The aim of this paper is to study the continuity of weak solutions for quasilinear degenerate parabolic equations of the form: μt-△φ(μ) = 0 ,where φ ε C1(R^1) is a strictly monotone increasing function. Cle...The aim of this paper is to study the continuity of weak solutions for quasilinear degenerate parabolic equations of the form: μt-△φ(μ) = 0 ,where φ ε C1(R^1) is a strictly monotone increasing function. Clearly, the above equation has strong degeneracy, i.e., the set of zero points of φ'(.) is permitted to have zero measure. This is an answer to an open problem in [13, p. 288].展开更多
The recently proposed weak form quadrature element method (QEM) is applied to flexural and vibrational analysis of thin plates The integrals involved in the variational description of a thin plate are evaluated by a...The recently proposed weak form quadrature element method (QEM) is applied to flexural and vibrational analysis of thin plates The integrals involved in the variational description of a thin plate are evaluated by an efficient numerical scheme and the par- tial derivatives at the integration sampling points are then approximated using differential quadrature analogs. Neither the grid pattern nor the number of nodes is fixed, being adjustable according to convergence need. The C~ continuity conditions char- acterizing the thin plate theory are discussed and the robustness of the weak form quadrature element for thin plates against shape distortion is examined. Examples are presented and comparisons with analytical solutions and the results of the finite element method are made to demonstrate the convergence and computational efficiency of the weak form quadrature element method. It is shown that the present formulation is applicable to thin plates with varying thickness as well as uniform plates.展开更多
Some results concerning weakly continuous selection for set-valued mappingare given and, applied to metric projection. Let Y be a subspace of a Banach space X.If Y is a separable reflexive Banach space,reinoved a firs...Some results concerning weakly continuous selection for set-valued mappingare given and, applied to metric projection. Let Y be a subspace of a Banach space X.If Y is a separable reflexive Banach space,reinoved a first category subset, the metricprojection is weakly lower semicontinnous and admits a weakly continuous selection.展开更多
This paper presents several examples of fundamental problems involving weak continuity and compactness for nonlinear partial differential equations, in which compensated compactness and related ideas have played a sig...This paper presents several examples of fundamental problems involving weak continuity and compactness for nonlinear partial differential equations, in which compensated compactness and related ideas have played a significant role. The compactness and convergence of vanishing viscosity solutions for nonlinear hyperbolic conservation laws are first analyzed, including the inviscid limit from the Navier-Stokes equations to the Euler equations for homentropic flow, the vanishing viscosity method to construct the global spherically symmetric solutions to the multidimensional compressible Euler equations, and the sonic-subsonic limit of solutions of the full Euler equations for multi-dimensional steady compressible fluids. Then the weak continuity and rigidity of the Gauss-Codazzi-Ricci system and corresponding isometric embeddings in differential geometry are revealed. Further references are also provided for some recent developments on the weak continuity and compactness for nonlinear partial differential equations.展开更多
文摘In this paper, some properties of the monotone set function defined by theChoquet integral are discussed. It is shown that several important structural characteristics of theoriginal set function, such as weak null-additivity, strong order continuity, property (s) andpseudomelric generating property, etc., are preserved by the new set function. It is also shown thatC-integrability assumption is inevitable for the preservations of strong order continuous andpseudometric generating property.
基金Foundation item: Supported by the NSF of Fujian(Z0511033)Supported by the Eduction Committee of Fujian(JB04298)Supported by the Eduction Committee of Henan (2004606018, 200510483002)
文摘In this paper, we prove that a space with a compact Countable weak base if and only if it is a weak open cs-image of a metric space.
文摘The roughness of the model function f(x) to the basis functions has been identified. When the model function is continuous segment, its roughness does not depend on the behavior of the first segment, but depends on "h", the shift in the slope of two consecutive segments. If the distribution of design is uniform, f(x) is continuous segment function, and h is constant, then the maximum roughness is h2/192 obtained at the midpoint of the observations. Suppose that we have a sequence of designs {Pn(x)} then its corresponding distribution {Fn (x)} converges weakly to some distribution F(x). Let D(f) be a set of discontinuous points off(x), it is possible to take the limit of the roughness if D(f) has zero (dF)-measure. The behavior of maximum roughness of the discontinuous segment function has been studied by using grid points.
基金Project supported by the Teaching and Research Award Fund for Outstanding Young Teachers in Higher Education Institutions of MOE(No.[2000]26)the 973 Project of the Ministry of Science and Technology of China(No.2006CB805902)+1 种基金the National Natural Science Foundation of China(No.10571072)the Key Laboratory of Symbolic Computation and Knowledge Engineering of the Ministry of Education of China and the 985 Project of Jilin University.
文摘The aim of this paper is to study the continuity of weak solutions for quasilinear degenerate parabolic equations of the form: μt-△φ(μ) = 0 ,where φ ε C1(R^1) is a strictly monotone increasing function. Clearly, the above equation has strong degeneracy, i.e., the set of zero points of φ'(.) is permitted to have zero measure. This is an answer to an open problem in [13, p. 288].
基金supported by the National Natural Science Foundation of China (Grant Nos.51178247 and 50778104)the National High Technology Research and Development Program of China (Grant No.2009AA04Z401)
文摘The recently proposed weak form quadrature element method (QEM) is applied to flexural and vibrational analysis of thin plates The integrals involved in the variational description of a thin plate are evaluated by an efficient numerical scheme and the par- tial derivatives at the integration sampling points are then approximated using differential quadrature analogs. Neither the grid pattern nor the number of nodes is fixed, being adjustable according to convergence need. The C~ continuity conditions char- acterizing the thin plate theory are discussed and the robustness of the weak form quadrature element for thin plates against shape distortion is examined. Examples are presented and comparisons with analytical solutions and the results of the finite element method are made to demonstrate the convergence and computational efficiency of the weak form quadrature element method. It is shown that the present formulation is applicable to thin plates with varying thickness as well as uniform plates.
基金Supported by the Natural Science Foundation of Hebei
文摘Some results concerning weakly continuous selection for set-valued mappingare given and, applied to metric projection. Let Y be a subspace of a Banach space X.If Y is a separable reflexive Banach space,reinoved a first category subset, the metricprojection is weakly lower semicontinnous and admits a weakly continuous selection.
基金supported by the UK EPSRC Science and Innovation Award to the Oxford Centre for Nonlinear PDE(No.EP/E035027/1)the UK EPSRC Award to the EPSRC Centre for Doctoral Training in PDEs(No.EP/L015811/1)+1 种基金the National Natural Science Foundation of China(No.10728101)the Royal Society-Wolfson Research Merit Award(UK)
文摘This paper presents several examples of fundamental problems involving weak continuity and compactness for nonlinear partial differential equations, in which compensated compactness and related ideas have played a significant role. The compactness and convergence of vanishing viscosity solutions for nonlinear hyperbolic conservation laws are first analyzed, including the inviscid limit from the Navier-Stokes equations to the Euler equations for homentropic flow, the vanishing viscosity method to construct the global spherically symmetric solutions to the multidimensional compressible Euler equations, and the sonic-subsonic limit of solutions of the full Euler equations for multi-dimensional steady compressible fluids. Then the weak continuity and rigidity of the Gauss-Codazzi-Ricci system and corresponding isometric embeddings in differential geometry are revealed. Further references are also provided for some recent developments on the weak continuity and compactness for nonlinear partial differential equations.