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SOME PROPERTIES OF THE INTEGRATION OPERATORS ON THE SPACES F(p,q,s)
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作者 陈家乐 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期173-188,共16页
We study the closed range property and the strict singularity of integration operators acting on the spaces F(p,pα-2,s).We completely characterize the closed range property of the Volterra companion operator I_(g)on ... We study the closed range property and the strict singularity of integration operators acting on the spaces F(p,pα-2,s).We completely characterize the closed range property of the Volterra companion operator I_(g)on F(p,pα-2,s),which generalizes the existing results and answers a question raised in[A.Anderson,Integral Equations Operator Theory,69(2011),no.1,87-99].For the Volterra operator J_(g),we show that,for 0<α≤1,J_(g)never has a closed range on F(p,pα-2,s).We then prove that the notions of compactness,weak compactness and strict singularity coincide in the case of J_(g)acting on F(p,p-2,s). 展开更多
关键词 integration operator closed range property strict singularity
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Precise integration method for a class of singular two-point boundary value problems 被引量:2
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作者 Wen-Zhi Zhang Pei-Yan Huang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2013年第2期233-240,共8页
In this paper we present a precise integration method based on high order multiple perturbation method and reduction method for solving a class of singular twopoint boundary value problems.Firstly,by employing the met... In this paper we present a precise integration method based on high order multiple perturbation method and reduction method for solving a class of singular twopoint boundary value problems.Firstly,by employing the method of variable coefficient dimensional expanding,the non-homogeneous ordinary differential equations(ODEs) are transformed into homogeneous ODEs.Then the interval is divided evenly,and the transfer matrix in every subinterval is worked out using the high order multiple perturbation method,and a set of algebraic equations is given in the form of matrix by the precise integration relation for each segment,which is worked out by the reduction method.Finally numerical examples are elaboratedd to validate the present method. 展开更多
关键词 singular two point boundary value problem Precise integration method High order multiple perturbation method reduction method
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Precise integration method for solving singular perturbation problems 被引量:1
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作者 富明慧 张文志 S.V.SHESHENIN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2010年第11期1463-1472,共10页
This paper presents a precise method for solving singularly perturbed boundary-value problems with the boundary layer at one end. The method divides the interval evenly and gives a set of algebraic equations in a matr... This paper presents a precise method for solving singularly perturbed boundary-value problems with the boundary layer at one end. The method divides the interval evenly and gives a set of algebraic equations in a matrix form by the precise integration relationship of each segment. Substituting the boundary conditions into the algebraic equations, the coefficient matrix can be transformed to the block tridiagonal matrix. Considering the nature of the problem, an efficient reduction method is given for solving singular perturbation problems. Since the precise integration relationship introduces no discrete error in the discrete process, the present method has high precision. Numerical examples show the validity of the present method. 展开更多
关键词 singular perturbation problem first-order ordinary differential equation two-point boundary-value problem precise integration method reduction method
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Research on Chaos of Nonlinear Singular Integral Equation
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作者 Yannan Liu Yu Wang 《Journal of Applied Mathematics and Physics》 2023年第4期1152-1159,共8页
In this paper, one class of nonlinear singular integral equation is discussed through Lagrange interpolation method. We research the connections between numerical solutions of the equations and chaos in the process of... In this paper, one class of nonlinear singular integral equation is discussed through Lagrange interpolation method. We research the connections between numerical solutions of the equations and chaos in the process of solving by iterative method. 展开更多
关键词 Lagrange Interpolation Method Nonlinear singular integral Equation Iterative Method
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On the Numerical Solution of Singular Integral Equation with Degenerate Kernel Using Laguerre Polynomials
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作者 Khadeejah Sultan Alroogy Musa Adam Aigo 《American Journal of Computational Mathematics》 2023年第1期153-160,共8页
In this paper, we derive a simple and efficient matrix formulation using Laguerre polynomials to solve the singular integral equation with degenerate kernel. This method is based on replacement of the unknown function... In this paper, we derive a simple and efficient matrix formulation using Laguerre polynomials to solve the singular integral equation with degenerate kernel. This method is based on replacement of the unknown function by truncated series of well known Laguerre expansion of functions. This leads to a system of algebraic equations with Laguerre coefficients. Thus, by solving the matrix equation, the coefficients are obtained. Some numerical examples are included to demonstrate the validity and applicability of the proposed method. 展开更多
关键词 singular integral Equation Projection Method Galerkin Method La-guerre Polynomials
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Distributed Reduced-order Optimal Fusion Kalman Filters for Stochastic Singular Systems 被引量:2
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作者 SUN Shu-Li MA Jing 《自动化学报》 EI CSCD 北大核心 2006年第2期286-290,共5页
Based on the optimal fusion algorithm weighted by matrices in the linear minimum variance (LMV) sense, a distributed full-order optimal fusion Kalman filter (DFFKF) is given for discrete-time stochastic singular syste... Based on the optimal fusion algorithm weighted by matrices in the linear minimum variance (LMV) sense, a distributed full-order optimal fusion Kalman filter (DFFKF) is given for discrete-time stochastic singular systems with multiple sensors, which involves the inverse of a high-dimension matrix to compute matrix weights. To reduce the computational burden, a distributed reduced-order fusion Kalman filter (DRFKF) is presented, which involves in parallel the inverses of two relatively low-dimension matrices to compute matrix weights. A simulation example shows the effectiveness. 展开更多
关键词 多传感器 信息融合 KALMAN滤波 随机奇异系统
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LOCAL SALINE APPROXIMATION METHODS FOR SINGULAR PRODUCT INTEGRATION 被引量:1
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作者 C. Dagnino V. Demichelis E. Santi 《Analysis in Theory and Applications》 1996年第3期37-51,共15页
The purpose of this paper is to propose and study local spline approximation methods for singular product integration,for which;i)the precision degree is the highest possible using splint approximation; ii) the nodes ... The purpose of this paper is to propose and study local spline approximation methods for singular product integration,for which;i)the precision degree is the highest possible using splint approximation; ii) the nodes fan be assumed equal to arbitrary points,where the integrand function f is known; iii) the number of the requested evaluations of f at the nodes is low,iv) a satisfactory convergence theory can be proved. 展开更多
关键词 LOCAL SALINE APPROXIMATION METHODS FOR singular PRODUCT integration
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On Convergence of Singular integral Operators With Respect to Path of Integration
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作者 Wang Xiaolin Lu Jianke 《Wuhan University Journal of Natural Sciences》 CAS 1996年第2期144-148,共5页
Given f being Holder continuous in a region GC. For the Cauchy principal integral where G is a smooth closed contour,lt is established that,if a sequence or smooth closed contours G(n ∈N ) smoothly convergent top,the... Given f being Holder continuous in a region GC. For the Cauchy principal integral where G is a smooth closed contour,lt is established that,if a sequence or smooth closed contours G(n ∈N ) smoothly convergent top,then the corresponding sequence I(Γm,f)is convergent to I (,f). Furthermore,when Γ is approximated by a sequence of complex cubic splines(Γ)interpolatory to Γ,the error is estimated. 展开更多
关键词 singular integral operator smooth convergence complex interpolatory spline
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Accurate Calculation of Equilibrium Reduced Density Matrix for the System-Bath Model:a Multilayer Multiconfiguration Time-Dependent Hartree Approach and its Comparison to a Multi-Electronic-State Path Integral Molecular Dynamics Approach
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作者 Haobin Wang Xinzijian Liu Jian Liu 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2018年第4期446-456,614,共12页
An efficient and accurate method for computing the equilibriurn reduced density matrix is presented for treating open quantum systems characterized by the systern-bath model. The method employs the rnultilayer nmltico... An efficient and accurate method for computing the equilibriurn reduced density matrix is presented for treating open quantum systems characterized by the systern-bath model. The method employs the rnultilayer nmlticonfiguration tirne-dependent Hartree theory for imag- inary time propagation and an importance sampling procedure for calculating the quantum mechanical trace. The method is applied to the spin-boson Harniltonian, which leads to ac- curate results in agreement with those produced by the rnulti-electronic-state path integral molecular dynamics method. 展开更多
关键词 Multilayer multiconfiguration time-dependent Hartree Path integral riurn reduced density matrix Imaginary time propagation
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Integral Representation of the Manifold Solution for New Class of the Volterra Type Integral Equation with a Boundary Singularity in the Case, When Kernel Contain Logarithmic Singularity and its Power
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作者 Nusrat Rajabov 《Journal of Mathematics and System Science》 2016年第1期23-37,共15页
In this work we suggestion new methods investigation the model Volterra type integral equation with logarithmic singularity, kernel which consisting from composition polynomial function with logarithmic singularity an... In this work we suggestion new methods investigation the model Volterra type integral equation with logarithmic singularity, kernel which consisting from composition polynomial function with logarithmic singularity and function with singular point. The problem investigation this type integral equation at n = 2m reduce to problem investigate the Volterra type integral equation (1) for n = 2 the theory for which was constructed in [2]. In this work, we investigation integral equation (1) at = 2m + 1 In this case, we investigate integral equation (1) reduction it's to m integral equation type [2] φ(x)+∫xa[p1+p2 ln(x-a/t-a)]φ(t)/t-a dt=f(x)and one the following integral equation [1] ω(x)+p3∫xω(t)/ a t-adt=g(x). 展开更多
关键词 singular kernel volterra type integral equation boundary singularity logarithmic singularity.
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UNIFORM DIFFERENCE SCHEME FOR A SINGULARLY PERTURBED LINEAR 2ND ORDER HYPERBOLIC PROBLEM WITH ZEROTH ORDER REDUCED EQUATION
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作者 苏煜城 林平 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1990年第4期301-313,共13页
In this paper a singularly perturbed linear second order hyperbolic problem with zeroth order reduced equation is discussed. Firstly, an energy inequality of the solution and an estimate of the remainder term of the a... In this paper a singularly perturbed linear second order hyperbolic problem with zeroth order reduced equation is discussed. Firstly, an energy inequality of the solution and an estimate of the remainder term of the asymptotic solution are given. Then an exponentially fitted difference scheme is developed in an equidistant mesh. Finally, uniform convergence in small parameter is proved in the sense of discrete energy norm. 展开更多
关键词 UNIFORM DIFFERENCE SCHEME FOR A singularLY PERTURBED LINEAR 2ND ORDER HYPERBOLIC PROBLEM WITH ZEROTH ORDER reduced EQUATION
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China Should Adopt Integration Policies to Reduce Energy Waste
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《China Oil & Gas》 CAS 2016年第3期1-1,共1页
China should pilot renewable energy integration policies similar to those adopted in Germany and Texas in the Beijing-Tianjin-Hebei region to transmit excess energy and reduce wasted wind power.Renewable energy integr... China should pilot renewable energy integration policies similar to those adopted in Germany and Texas in the Beijing-Tianjin-Hebei region to transmit excess energy and reduce wasted wind power.Renewable energy integration will be fundamental to China?s transition to a low-carbon economy.Although China now leads the world in terms 展开更多
关键词 WILL China Should Adopt integration Policies to reduce Energy Waste HIGH
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L^p Boundedness of Commutators of Calderón-Zygmund Singular Integral Operators 被引量:8
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作者 邓东皋 颜立新 《数学进展》 CSCD 北大核心 1998年第3期259-269,共11页
本文证明了当b∈BMO时,具有弱核的CalderónZygmund奇异积分算子的交换子[b,T]f=bT(f)-T(bf)是Lp(1<p<∞)有界的.一个等价的命题是双线性算子gT(f)-fT(g)∈H1,只... 本文证明了当b∈BMO时,具有弱核的CalderónZygmund奇异积分算子的交换子[b,T]f=bT(f)-T(bf)是Lp(1<p<∞)有界的.一个等价的命题是双线性算子gT(f)-fT(g)∈H1,只要f∈Lp,g∈Lq,1<p<∞,1p+1q=1. 展开更多
关键词 交换子 HARDY空间 奇异积分算子 L^P有界性
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Study on Characteristics of 3-D Translating-Pulsating Source Green Function of Deep-Water Havelock Form and Its Fast Integration Method 被引量:19
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作者 许勇 董文才 《China Ocean Engineering》 SCIE EI 2011年第3期365-380,共16页
The singularities, oscillatory performances and the contributing factors to the 3-'D translating-pulsating source Green function of deep-water Havelock form which consists of a local disturbance part and a far-field ... The singularities, oscillatory performances and the contributing factors to the 3-'D translating-pulsating source Green function of deep-water Havelock form which consists of a local disturbance part and a far-field wave-like part, are analyzed systematically. Relative numerical integral methods about the two parts are presented in this paper. An improved method based on LOBATTO rule is used to eliminate singularities caused respectively by infinite discontinuity and jump discontinuous node from the local disturbance part function, which makes the improvement of calculation efficiency and accuracy possible. And variable substitution is applied to remove the singularity existing at the end of the integral interval of the far-field wave-like part function. Two auxiliary techniques such as valid interval calculation and local refinement of integral steps technique in narrow zones near false singularities are applied so as to avoid unnecessary integration of invalid interval and improve integral accordance. Numerical test results have proved the efficiency and accuracy in these integral methods that thus can be applied to calculate hydrodynamic performance of floating structures moving in waves. 展开更多
关键词 translating-pulsating source Green's function singularity highly oscillatory function integration method
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Multilinear singular integrals and commutators in variable exponent Lebesgue spaces 被引量:24
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作者 HUANG Ai-wu XU Jing-shi 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2010年第1期69-77,共9页
Boundedness of multilinear singular integrals and their commutators from products of variable exponent Lebesgue spaces to variable exponent Lebesgue spaces are obtained. The vector-valued case is also considered.
关键词 Multilinear singular integral COMMUTATOR variable exponent Lebesgue space BMO function maximal operator.
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COMMUTATORS OF SINGULAR INTEGRAL OPERATORS WITH NON-SMOOTH KERNELS 被引量:10
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作者 邓东皋 颜立新 《Acta Mathematica Scientia》 SCIE CSCD 2005年第1期137-144,共8页
Let T be a singular integral operator bounded on Lp(Rn) for some p, 1 < p < ∞. The authors give a sufficient condition on the kernel of T so that when b ∈BMO, the commutator [b,T](f) = T(bf) - bT(f) is bounded... Let T be a singular integral operator bounded on Lp(Rn) for some p, 1 < p < ∞. The authors give a sufficient condition on the kernel of T so that when b ∈BMO, the commutator [b,T](f) = T(bf) - bT(f) is bounded on the space Lp for all p, 1 < p < ∞. The condition of this paper is weaker than the usual pointwise Hormander condition. 展开更多
关键词 COMMUTATOR BMO singular integrals semigroup kernel
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INTERIOR ESTIMATES IN MORREY SPACES FOR SOLUTIONS OF ELLIPTIC EQUATIONS AND WEIGHTED BOUNDEDNESS FOR COMMUTATORS OF SINGULAR INTEGRAL OPERATORS 被引量:14
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作者 刘岚喆 《Acta Mathematica Scientia》 SCIE CSCD 2005年第1期89-94,共6页
It is proved that, for the nondivergence elliptic equations Σi,jn=1aijuxixj=f, if f belongs to the generalized Morrey spaces Lp, (w), then uxixj ∈ Lp, (w), where u is the W2,p-solution of the equations. In order to ... It is proved that, for the nondivergence elliptic equations Σi,jn=1aijuxixj=f, if f belongs to the generalized Morrey spaces Lp, (w), then uxixj ∈ Lp, (w), where u is the W2,p-solution of the equations. In order to obtain this, the author first establish the weighted boundedness for the commutators of some singular integral operators on Lp, (w). 展开更多
关键词 Nondivergence elliptic equation generalized Morrey space commutator of singular integral operator Ap weight
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Commutators of Multilinear Singular Integrals with Lipschitz Functions 被引量:9
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作者 WANG WEI XU JING-SHI 《Communications in Mathematical Research》 CSCD 2009年第4期318-328,共11页
The boundedness of commutators of multilinear singular integrals with Lipschitz functions in product Lebesgue spaces is obtained.
关键词 multilinear singular integral Lipschitz function COMMUTATOR maximalfunction
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SINGULAR INTEGRAL EQUATIONS ALONG AN OPEN ARC WITH SOLUTIONS HAVING SINGULARITIES OF HIGHER ORDER 被引量:5
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作者 钟寿国 《Acta Mathematica Scientia》 SCIE CSCD 2005年第2期193-200,共8页
In this paper, the difficulties on calculation in solving singular integral equations are overcome when the restriction of curve of integration to be a closed contour is cancelled. When the curve is an open arc and th... In this paper, the difficulties on calculation in solving singular integral equations are overcome when the restriction of curve of integration to be a closed contour is cancelled. When the curve is an open arc and the solutions for singular integral equations possess singularities of higher order, the solution and the solvable condition for characteristic equations as well as the generalized Noether theorem for complete equations are given. 展开更多
关键词 Open arc singular integral equation solutions with singularity of higher order Noether theorem characteristic equation
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Boundary properties for several singular integral operators in real Clifford analysis 被引量:7
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作者 YANG He-ju XIE Yong-hong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2010年第3期349-358,共10页
On the basis of the Cauchy integral formulas for regular and biregular functions, we define some Cauchy-type singular integral operators. Then we discuss the Holder continuous property of some singular integral operat... On the basis of the Cauchy integral formulas for regular and biregular functions, we define some Cauchy-type singular integral operators. Then we discuss the Holder continuous property of some singular integral operators with one integral variable. Then we divide a singular integral operator with two variables into three parts and prove its Holder continuous property on the boundary. 展开更多
关键词 singular integral operator Holder continuous function boundary property.
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