In this paper, we first discuss the methods of comparing two special absolutely convergentsine series, sinnx and sinnx. We state the theorem in.one dimensional case as follows; Theorem. Let be convergent series with n...In this paper, we first discuss the methods of comparing two special absolutely convergentsine series, sinnx and sinnx. We state the theorem in.one dimensional case as follows; Theorem. Let be convergent series with nonnegative terms. SupposeThen for all x∈[0,π]If, in addition, then展开更多
This note is devoted to the study of the absolute convergence of Bernstein polynomials. It is proved that for each x∈ , the sequence of the Bernstein polynomials of a function of bounded variation is absolutely su...This note is devoted to the study of the absolute convergence of Bernstein polynomials. It is proved that for each x∈ , the sequence of the Bernstein polynomials of a function of bounded variation is absolutely summable by |C,1| method. Moreover, the estimate of the remainders of the |C,1| sum of the sequence of the Bernstein polynomials is obtained.展开更多
A space-time coupled spectral element method based on Chebyshev polynomials is presented for solving time-dependent wave equations.Acoustic propagation problems in1+1,2+1,3+1 dimensions with the Dirichlet boundary ...A space-time coupled spectral element method based on Chebyshev polynomials is presented for solving time-dependent wave equations.Acoustic propagation problems in1+1,2+1,3+1 dimensions with the Dirichlet boundary conditions are simulated via space-time coupled spectral element method using quadrilateral,hexahedral and tesseractic elements respectively.Space-time coupled spectral element method can obtain high-order precision over time.With the same total number of nodes,higher numerical precision is obtained if the higher-order Chebyshev polynomials in space directions and lower-order Chebyshev polynomials in time direction are adopted.Numerical illustrations have indicated that the space-time algorithm provides higher precision than the semi-discretization.When space-time coupled spectral element method is used,time subdomain-by-subdomain approach is more economical than time domain approach.展开更多
文摘In this paper, we first discuss the methods of comparing two special absolutely convergentsine series, sinnx and sinnx. We state the theorem in.one dimensional case as follows; Theorem. Let be convergent series with nonnegative terms. SupposeThen for all x∈[0,π]If, in addition, then
文摘This note is devoted to the study of the absolute convergence of Bernstein polynomials. It is proved that for each x∈ , the sequence of the Bernstein polynomials of a function of bounded variation is absolutely summable by |C,1| method. Moreover, the estimate of the remainders of the |C,1| sum of the sequence of the Bernstein polynomials is obtained.
基金supported by the the State Plan for Development of Basic Research in Key Area(973Project)(2012CB026004)
文摘A space-time coupled spectral element method based on Chebyshev polynomials is presented for solving time-dependent wave equations.Acoustic propagation problems in1+1,2+1,3+1 dimensions with the Dirichlet boundary conditions are simulated via space-time coupled spectral element method using quadrilateral,hexahedral and tesseractic elements respectively.Space-time coupled spectral element method can obtain high-order precision over time.With the same total number of nodes,higher numerical precision is obtained if the higher-order Chebyshev polynomials in space directions and lower-order Chebyshev polynomials in time direction are adopted.Numerical illustrations have indicated that the space-time algorithm provides higher precision than the semi-discretization.When space-time coupled spectral element method is used,time subdomain-by-subdomain approach is more economical than time domain approach.