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A POSTERIORI ERROR ESTIMATION OF THE NEW MIXED ELEMENT SCHEMES FOR SECOND ORDER ELLIPTIC PROBLEM ON ANISOTROPIC MESHES
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作者 王培珍 陈绍春 《Acta Mathematica Scientia》 SCIE CSCD 2014年第5期1510-1518,共9页
This paper presents a posteriori residual error estimator for the new mixed el-ement scheme for second order elliptic problem on anisotropic meshes. The reliability and efficiency of our estimator are established with... This paper presents a posteriori residual error estimator for the new mixed el-ement scheme for second order elliptic problem on anisotropic meshes. The reliability and efficiency of our estimator are established without any regularity assumption on the mesh. 展开更多
关键词 error estimator anisotropic meshes new mixed element schemes
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A REFINEMENT OF THE SCHWARZ-PICK ESTIMATES AND THE CARATHéODORY METRIC IN SEVERAL COMPLEX VARIABLES
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作者 Xiaosong LIU Taishun LIU 《Acta Mathematica Scientia》 SCIE CSCD 2024年第4期1337-1346,共10页
In this article,we first establish an asymptotically sharp result on the higher order Fréchet derivatives for bounded holomorphic mappings f(x)=f(0)+∞∑s=1Dskf(0)(x^(sk))/(sk)!:B_(X)→B_(Y),where B_X is the unit... In this article,we first establish an asymptotically sharp result on the higher order Fréchet derivatives for bounded holomorphic mappings f(x)=f(0)+∞∑s=1Dskf(0)(x^(sk))/(sk)!:B_(X)→B_(Y),where B_X is the unit ball of X.We next give a sharp result on the first order Fréchet derivative for bounded holomorphic mappings F(X)=F(0+)∞∑s=KD^(s)f(0)(x^(8)/s!):B_(X)→B_(Y),where B_(X)is the unit ball of X.The results that we derive include some results in several complex variables,and extend the classical result in one complex variable to several complex variables. 展开更多
关键词 refined Schwarz-Pick estimate bounded holomorphic mapping Carathéodory metric first order Fréchet derivative higher order Fréchet derivatives
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THE SUPERIORITY OF EMPIRICAL BAYES ESTIMATION OF PARAMETERS IN PARTITIONED NORMAL LINEAR MODEL 被引量:4
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作者 张伟平 韦来生 《Acta Mathematica Scientia》 SCIE CSCD 2008年第4期955-962,共8页
In this article,the empirical Bayes(EB)estimators are constructed for the estimable functions of the parameters in partitioned normal linear model.The superiorities of the EB estimators over ordinary least-squares... In this article,the empirical Bayes(EB)estimators are constructed for the estimable functions of the parameters in partitioned normal linear model.The superiorities of the EB estimators over ordinary least-squares(LS)estimator are investigated under mean square error matrix(MSEM)criterion. 展开更多
关键词 Partitioned linear model empirical Bayes estimator least-squares estimator mean square error matrix
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On the Error Estimate of Adini's Element for the Second Order Problems 被引量:1
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作者 高继梅 李文华 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2007年第3期364-369,共6页
The main aim of this paper is to have an accurate analysis on the famous Adini's element for the second order problems under to the anisotropic meshes. We firstly show that the interpolation of Adini's element satis... The main aim of this paper is to have an accurate analysis on the famous Adini's element for the second order problems under to the anisotropic meshes. We firstly show that the interpolation of Adini's element satisfy the anisotropic property. Then the optimal error estimate is obtained without the regularity assumption on the meshes. 展开更多
关键词 Adini's element ANISOTROPIC regularity assumption error estimate
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Error Estimates of H^1-Galerkin Mixed Methods for the Viscoelasticity Wave Equation 被引量:1
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作者 WANG Jin-feng~,LIU Yang~,LI Hong~(1. LIU Yang LI Hong 《Chinese Quarterly Journal of Mathematics》 CSCD 2011年第1期131-137,共7页
H1-Galerkin mixed methods are proposed for viscoelasticity wave equation.Depending on the physical quantities of interest,two methods are discussed.The optimal error estimates and the proof of the existence and unique... H1-Galerkin mixed methods are proposed for viscoelasticity wave equation.Depending on the physical quantities of interest,two methods are discussed.The optimal error estimates and the proof of the existence and uniqueness of semidiscrete solutions are derived for problems in one space dimension.And the methods don't require the LBB condition. 展开更多
关键词 viscoelasticity wave equation H1-Galerkin mixed finite element methods existence and uniqueness optimal error estimates
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AN ASYMPTOTIC BEHAVIOR AND A POSTERIORI ERROR ESTIMATES FOR THE GENERALIZED SCHWARTZ METHOD OF ADVECTION-DIFFUSION EQUATION
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作者 Salah BOULAARAS Mohammed Said TOUATI BRAHIM +1 位作者 Smail BOUZENADA Abderrahmane ZARAI 《Acta Mathematica Scientia》 SCIE CSCD 2018年第4期1227-1244,共18页
In this paper, a posteriori error estimates for the generalized Schwartz method with Dirichlet boundary conditions on the interfaces for advection-diffusion equation with second order boundary value problems are prove... In this paper, a posteriori error estimates for the generalized Schwartz method with Dirichlet boundary conditions on the interfaces for advection-diffusion equation with second order boundary value problems are proved by using the Euler time scheme combined with Galerkin spatial method. Furthermore, an asymptotic behavior in Sobolev norm is de- duced using Benssoussau-Lions' algorithm. Finally, the results of some numerical experiments are presented to support the theory. 展开更多
关键词 a posteriori error estimates GODDM ADVECTION-DIFFUSION Galerkin method Benssoussan-Lions' algorithm
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Empirical Bayes Absolute Error Loss Estimation for Parameter of One-Side Truncation Distribution Families
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作者 李金平 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第2期20-22,共3页
In this paper we propose an absolute error loss EB estimator for parameter of one-side truncation distribution families. Under some conditions we have proved that the convergence rates of its Bayes risk is o, where 0&... In this paper we propose an absolute error loss EB estimator for parameter of one-side truncation distribution families. Under some conditions we have proved that the convergence rates of its Bayes risk is o, where 0<λ,r≤1,Mn≤lnln n (for large n),Mn→∞ as n→∞. 展开更多
关键词 one-side truncation distribution families absolute error loss function empirical Bayes estimator convergence rates
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THE LARGE TIME BEHAVIOR OF SPECTRAL APPROXIMATION FOR A CLASS OF PSEUDOPARABOLIC VISCOUS DIFFUSION EQUATION 被引量:4
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作者 尚亚东 《Acta Mathematica Scientia》 SCIE CSCD 2007年第1期153-168,共16页
The asymptotic behavior of the solutions to a class of pseudoparabolic viscous diffusion equation with periodic initial condition is studied by using the spectral method. The semidiscrete Fourier approximate solution ... The asymptotic behavior of the solutions to a class of pseudoparabolic viscous diffusion equation with periodic initial condition is studied by using the spectral method. The semidiscrete Fourier approximate solution of the problem is constructed and the error estimation between spectral approximate solution and exact solution on large time is also obtained. The existence of the approximate attractor AN and the upper semicontinuity d(AN,A) → 0 are proved. 展开更多
关键词 Pseudoparabolic diffusion equation VISCOSITY spectral methods long time behavior large time error estimates
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A MODIFIED TIKHONOV REGULARIZATION METHOD FOR THE CAUCHY PROBLEM OF LAPLACE EQUATION 被引量:3
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作者 杨帆 傅初黎 李晓晓 《Acta Mathematica Scientia》 SCIE CSCD 2015年第6期1339-1348,共10页
In this paper, we consider the Cauchy problem for the Laplace equation, which is severely ill-posed in the sense that the solution does not depend continuously on the data. A modified Tikhonov regularization method is... In this paper, we consider the Cauchy problem for the Laplace equation, which is severely ill-posed in the sense that the solution does not depend continuously on the data. A modified Tikhonov regularization method is proposed to solve this problem. An error estimate for the a priori parameter choice between the exact solution and its regularized approximation is obtained. Moreover, an a posteriori parameter choice rule is proposed and a stable error estimate is also obtained. Numerical examples illustrate the validity and effectiveness of this method. 展开更多
关键词 Cauchy problem for Laplace equation ill-posed problem a posteriori parameterchoice error estimate
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FINITE DIFFERENCE FRACTIONAL STEP METHODS FOR THE TRANSIENT BEHAVIOR OF A SEMICONDUCTOR DEVICE 被引量:4
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作者 袁益让 《Acta Mathematica Scientia》 SCIE CSCD 2005年第3期427-438,共12页
Characteristic finite difference fractional step schemes are put forward. The electric potential equation is described by a seven-point finite difference scheme, and the electron and hole concentration equations are t... Characteristic finite difference fractional step schemes are put forward. The electric potential equation is described by a seven-point finite difference scheme, and the electron and hole concentration equations are treated by a kind of characteristic finite difference fractional step methods. The temperature equation is described by a fractional step method. Thick and thin grids are made use of to form a complete set. Piecewise threefold quadratic interpolation, symmetrical extension, calculus of variations, commutativity of operator product, decomposition of high order difference operators and prior estimates are also made use of. Optimal order estimates in l2 norm are derived to determine the error of the approximate solution. The well-known problem is thorongley and completely solred. 展开更多
关键词 General region semiconductor device 3-dimensional heat conduction characteristic finite difference parallel fractional steps l^2 error estimate.
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EXPLICIT ERROR ESTIMATE FOR THE NONCONFORMING WILSON'S ELEMENT 被引量:3
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作者 赵纪坤 陈绍春 《Acta Mathematica Scientia》 SCIE CSCD 2013年第3期839-846,共8页
In this article, we study the explicit expressions of the constants in the error estimate of the nonconforming finite element method. We explicitly obtain the approximation error estimate and the consistency error est... In this article, we study the explicit expressions of the constants in the error estimate of the nonconforming finite element method. We explicitly obtain the approximation error estimate and the consistency error estimate for the Wilson's element without the regular assumption, respectively, which implies the final finite element error estimate. Such explicit a priori error estimates can be used as computable error bounds. 展开更多
关键词 Nonconforming finite element explicit error estimate Wilson's element
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Robust state of charge estimation of lithium-ion battery via mixture kernel mean p-power error loss LSTM with heap-based-optimizer 被引量:1
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作者 Wentao Ma Yiming Lei +1 位作者 Xiaofei Wang Badong Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第5期768-784,I0016,共18页
The state of charge(SOC)estimation of lithium-ion battery is an important function in the battery management system(BMS)of electric vehicles.The long short term memory(LSTM)model can be employed for SOC estimation,whi... The state of charge(SOC)estimation of lithium-ion battery is an important function in the battery management system(BMS)of electric vehicles.The long short term memory(LSTM)model can be employed for SOC estimation,which is capable of estimating the future changing states of a nonlinear system.Since the BMS usually works under complicated operating conditions,i.e the real measurement data used for model training may be corrupted by non-Gaussian noise,and thus the performance of the original LSTM with the mean square error(MSE)loss may deteriorate.Therefore,a novel LSTM with mixture kernel mean p-power error(MKMPE)loss,called MKMPE-LSTM,is developed by using the MKMPE loss to replace the MSE as the learning criterion in LSTM framework,which can achieve robust SOC estimation under the measurement data contaminated with non-Gaussian noises(or outliers)because of the MKMPE containing the p-order moments of the error distribution.In addition,a meta-heuristic algorithm,called heap-based-optimizer(HBO),is employed to optimize the hyper-parameters(mainly including learning rate,number of hidden layer neuron and value of p in MKMPE)of the proposed MKMPE-LSTM model to further improve its flexibility and generalization performance,and a novel hybrid model(HBO-MKMPE-LSTM)is established for SOC estimation under non-Gaussian noise cases.Finally,several tests are performed under various cases through a benchmark to evaluate the performance of the proposed HBO-MKMPE-LSTM model,and the results demonstrate that the proposed hybrid method can provide a good robustness and accuracy under different non-Gaussian measurement noises,and the SOC estimation results in terms of mean square error(MSE),root MSE(RMSE),mean absolute relative error(MARE),and determination coefficient R2are less than 0.05%,3%,3%,and above 99.8%at 25℃,respectively. 展开更多
关键词 SOC estimation Long short term memory model Mixture kernel mean p-power error Heap-based-optimizer Lithium-ion battery Non-Gaussian noisy measurement data
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CONVERGENCE OF THE CRANK-NICOLSON/NEWTON SCHEME FOR NONLINEAR PARABOLIC PROBLEM
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作者 冯新龙 何银年 《Acta Mathematica Scientia》 SCIE CSCD 2016年第1期124-138,共15页
In this paper, the Crank-Nicolson/Newton scheme for solving numerically second- order nonlinear parabolic problem is proposed. The standard Galerkin finite element method based on P2 conforming elements is used to the... In this paper, the Crank-Nicolson/Newton scheme for solving numerically second- order nonlinear parabolic problem is proposed. The standard Galerkin finite element method based on P2 conforming elements is used to the spatial discretization of the problem and the Crank-Nieolson/Newton scheme is applied to the time discretization of the resulted finite element equations. Moreover, assuming the appropriate regularity of the exact solution and the finite element solution, we obtain optimal error estimates of the fully discrete Crank- Nicolson/Newton scheme of nonlinear parabolic problem. Finally, numerical experiments are presented to show the efficient performance of the proposed scheme. 展开更多
关键词 nonlinear parabolic problem Crank-Nicolson scheme Newton method finiteelement method optimal error estimate
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AUTOMATIC AUGMENTED GALERKIN ALGORITHMS FOR FREDHOLM INTEGRAL EQUATIONS OF THE FIRST KIND
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作者 S.Abbasbandy E.Babolian 《Acta Mathematica Scientia》 SCIE CSCD 1997年第1期69-84,共16页
In recent papers, Babolian & Delves [2] and Belward[3] described a Chebyshev series method for the solution of first kind integral equations. The expansion coefficients of the solution are determined as the soluti... In recent papers, Babolian & Delves [2] and Belward[3] described a Chebyshev series method for the solution of first kind integral equations. The expansion coefficients of the solution are determined as the solution of a mathematical programming problem.The method involves two regularization parameters, Cf and r, but values assigned to these parameters are heuristic in nature. Essah & Delves[7] described an algorithm for setting these parameters automatically, but it has some difficulties. In this paper we describe three iterative algorithms for computing these parameters for singular and non-singular first kind integral equations. We give also error estimates which are cheap to compute. Finally, we give a number of numerical examples showing that these algorithms work well in practice. 展开更多
关键词 Fredholm integral equations Galerkin method Regularization parameters error estimation Ill-Posed problems Product of chebyshev series
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Performance and Improvement of MCS Selection with Channel Quality Estimation Errors for HSDPA
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作者 贾民丽 匡镜明 +1 位作者 万蕾 费泽松 《Journal of Beijing Institute of Technology》 EI CAS 2006年第4期462-466,共5页
The throughput performance of modulation and coding schemes (MCS) selection with channel quality estimation errors (CQEE) is analyzed for high-speed downlink packet access (HSDPA). To reduce the loss of throughp... The throughput performance of modulation and coding schemes (MCS) selection with channel quality estimation errors (CQEE) is analyzed for high-speed downlink packet access (HSDPA). To reduce the loss of throughput caused by CQEE, the robust MCS selection method and adaptive MCS switching scheme are proposed. In addition, automatic repeat request (ARQ) scheme is used to improve the block error rate (BLER) performance. Simulation results show that the proposed methods decrease the throughput loss resulted from CQEE efficiently and BLER performance gets better with ARQ scheme. 展开更多
关键词 high-speed downlink packet access (HSDPA) modulation and coding scheme (MCS) channel quality estimation error (CQEE) automatic repeat request (ARQ)
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On the problem of the dynamical reactions of a rolling wheelset to real track irregularities
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作者 Hans True Lasse Engbo Christiansen +2 位作者 Andreas Lindhardt Plesner Andreas Lønstrup Ammitzbøll Bjørn Jerram Dahl 《Railway Engineering Science》 2023年第1期1-19,共19页
We investigate numerically the dynamical reactions of a moving wheelset model to real measured track irregularities.The background is to examine whether the dynamics are suitable as the input to the inverse problem:de... We investigate numerically the dynamical reactions of a moving wheelset model to real measured track irregularities.The background is to examine whether the dynamics are suitable as the input to the inverse problem:determine the true track geometry from measured wheelset dynamical reactions.It is known that the method works well for the vertical position of the rails but the computed lateral position is often flawed.We find that the lateral motion of the wheelset often may differ from the track geometry.The cases are investigated closely but the reasons remain unknown.While the wheelset dynamics reflect the larger(>4-6 mm)aperiodic track disturbances and single large disturbances quite well,this does not seem to be the case for general smaller or periodic track irregularities or sections behind single large disturbances.The resulting dynamics of a wheelset to lateral track irregularities are in general not sufficiently accurate to be used as the basis for a description of the track irregularities. 展开更多
关键词 Track monitoring Vehicle dynamical response Inverse problem Numerical analysis Estimate of errors Track irregularity
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The Integral Representations and Their Applications on the Analytic Varieties of Bounded Domains in Stein Manifolds
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作者 CHEN Shu-jin 《Chinese Quarterly Journal of Mathematics》 2021年第4期331-355,共25页
In this paper,we first obtain a unified integral representation on the analytic varieties of the general bounded domain in Stein manifolds(the two types bounded domains in[3]are regarded as its special cases).Secondly... In this paper,we first obtain a unified integral representation on the analytic varieties of the general bounded domain in Stein manifolds(the two types bounded domains in[3]are regarded as its special cases).Secondly we get the integral formulas of the solution of∂-equation.And we use a new and unique method to give a uniform estimate of the solution of∂-equation,which is different from Henkin's method. 展开更多
关键词 ∂-equation Uniform estimation General bounded domain Stein manifold Analytic varieties Integral representation
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Error Coefficient Estimation of Inertial Platform in Its Calibration
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作者 赵大炜 訾方 +1 位作者 张科 李言俊 《Defence Technology(防务技术)》 SCIE EI CAS 2005年第1期109-112,共4页
The error coefficient estimation of inertial platform in the course of its consecutive ground calibration is studied.A separate-bias algorithm is adopted to estimate the error parameters effectively. The ill-condition... The error coefficient estimation of inertial platform in the course of its consecutive ground calibration is studied.A separate-bias algorithm is adopted to estimate the error parameters effectively. The ill-conditioning problem of the equation solution caused by the huge state dimension is also resolved. And the simulation result shows its validity. 展开更多
关键词 惯性平台 误差系数 校准方法 制导估计 独立算法
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A REDUCED MFE FORMULATION BASED ON POD FOR THE NON-STATIONARY CONDUCTION-CONVECTION PROBLEMS 被引量:8
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作者 罗振东 谢正辉 陈静 《Acta Mathematica Scientia》 SCIE CSCD 2011年第5期1765-1785,共21页
In this article, a reduced mixed finite element (MFE) formulation based on proper orthogonal decomposition (POD) for the non-stationary conduction-convection problems is presented. Also the error estimates between... In this article, a reduced mixed finite element (MFE) formulation based on proper orthogonal decomposition (POD) for the non-stationary conduction-convection problems is presented. Also the error estimates between the reduced MFE solutions based on POD and usual MFE solutions are derived. It is shown by numerical examples that the results of numerical computation are consistent with theoretical conclusions. Moreover, it is shown that the reduced MFE formulation based on POD is feasible and efficient in finding numerical solutions for the non-stationary conduction-convection problems. 展开更多
关键词 proper orthogonal decomposition mixed finite element formulation error estimate non-stationary conduction-convection problems
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A NEW NONCONFORMING MIXED FINITE ELEMENT SCHEME FOR THE STATIONARY NAVIER-STOKES EQUATIONS 被引量:8
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作者 石东洋 任金城 龚伟 《Acta Mathematica Scientia》 SCIE CSCD 2011年第2期367-382,共16页
In this article, a new stable nonconforming mixed finite element scheme is proposed for the stationary Navier-Stokes equations, in which a new low order Crouzeix- Raviart type nonconforming rectangular element is take... In this article, a new stable nonconforming mixed finite element scheme is proposed for the stationary Navier-Stokes equations, in which a new low order Crouzeix- Raviart type nonconforming rectangular element is taken for approximating space for the velocity and the piecewise constant element for the pressure. The optimal order error estimates for the approximation of both the velocity and the pressure in L2-norm are established, as well as one in broken H1-norm for the velocity. Numerical experiments are given which are consistent with our theoretical analysis. 展开更多
关键词 Stationary Navier-Stokes equations nonconforming mixed finite elementscheme optimal order error estimates
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