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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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The Error Estimates of Direct Discontinuous Galerkin Methods Based on Upwind-Baised Fluxes 被引量:1
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作者 Hui Bi Yixin Chen 《Journal of Applied Mathematics and Physics》 2020年第12期2964-2970,共7页
<div style="text-align:justify;"> In this paper, we study the error estimates for direct discontinuous Galerkin methods based on the upwind-biased fluxes. We use a newly global projection to obtain the... <div style="text-align:justify;"> In this paper, we study the error estimates for direct discontinuous Galerkin methods based on the upwind-biased fluxes. We use a newly global projection to obtain the optimal error estimates. The numerical experiments imply that <em>L</em><sup>2 </sup>norms error estimates can reach to order <em>k</em> + 1 by using time discretization methods. </div> 展开更多
关键词 Direct Discontinuous Galerkin Methods Global Projection error estimates the Upwind-Biased Fluxes
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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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THE ERROR ESTIMATES OF HALLEY'S METHOD
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作者 韩丹夫 王兴华 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 1997年第2期231-240,共10页
In this paper we give an almost sharp error estimate of Halley’s iteration for the majorizing sequence. Compared with the corresponding results in [6,14], it is far better. Meanwhile,the convergence theorem is establ... In this paper we give an almost sharp error estimate of Halley’s iteration for the majorizing sequence. Compared with the corresponding results in [6,14], it is far better. Meanwhile,the convergence theorem is established .for Halley’s iteration in Banach spaces. 展开更多
关键词 Halley’s METHOD error estimateS majorizing function CONVERGENCE theorem.
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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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THE LARGE TIME ERROR ESTIMATES OF FOURIER SPECTRAL METHOD FOR GENERALIZED BENJAMIN-BONA-MAHONY EQUATIONS
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作者 ShangYadong GuoBoling 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2003年第1期17-29,共13页
In this paper, a spectral method to analyze the generalized Benjamin Bona Mahony equations is used. The existence and uniqueness of global smooth solution of these equations are proved. The large time error estimati... In this paper, a spectral method to analyze the generalized Benjamin Bona Mahony equations is used. The existence and uniqueness of global smooth solution of these equations are proved. The large time error estimation between the spectral approximate solution and the exact solution is obtained. 展开更多
关键词 Benjamin-Bona-Mahony equation Fourier spectral method error estimate.
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A POSTERIORI ERROR ESTIMATE OF THE DSD METHOD FOR FIRST-ORDER HYPERBOLIC EQUATIONS
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作者 KANG Tong(康彤) +1 位作者 YU De-hao(余德浩) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第6期732-740,共9页
A posteriori error estimate of the discontinuous-streamline diffusion method for first-order hyperbolic equations was presented, which can be used to adjust space mesh reasonably. A numerical example is given to illus... A posteriori error estimate of the discontinuous-streamline diffusion method for first-order hyperbolic equations was presented, which can be used to adjust space mesh reasonably. A numerical example is given to illustrate the accuracy and feasibility of this method. 展开更多
关键词 posteriori error estimate discontinuous-streamline diffusion method first-order hyperbolic equation
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Application of Variance Component Analysis (ANOVA) in Setup Errors and PTV Margins for Lung Cancer with Stereotactic Body Radiation Therapy (SBRT)
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作者 Xiaotian Huang Jun Zhang +2 位作者 Conghua Xie Yunfeng Zhou Hong Quan 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2018年第4期522-538,共17页
Purpose: To investigate the feasibility of applying ANOVA newly proposed by Yukinori to verify the setup errors, PTV (Planning Target Volume) margins, DVH for lung cancer with SBRT. Methods: 20 patients receiving SBRT... Purpose: To investigate the feasibility of applying ANOVA newly proposed by Yukinori to verify the setup errors, PTV (Planning Target Volume) margins, DVH for lung cancer with SBRT. Methods: 20 patients receiving SBRT to 50 Gy in 5 fractions with a Varian iX linear acceleration were selected. Each patient was scanned with kV-CBCT before the daily treatment to verify the setup position. Two other error calculation methods raised by Van Herk and Remeijer were also compared to discover the statistical difference in systematic errors (Σ), random errors (σ), PTV margins and DVH. Results: Utilizing two PTV margin calculation formulas (Stroom, Van Herk), PTV calculated by Yukinori method in three directions were (5.89 and 3.95), (5.54 and 3.55), (3.24 and 0.78) mm;Van Herk method were (6.10 and 4.25), (5.73 and 3.83), (3.51 and 1.13) mm;Remeijer method were (6.39 and 4.57), (5.98 and 4.10), (3.69 and 1.33) mm. The volumes of PTV using Yukinori method were significantly smaller (P < 0.05) than Van Herk method and Remeijer method. However, dosimetric indices of PTV (D98, D50, D2) and for OARs (Mean Dose, V20, V5) had no significant difference (P > 0.05) among three methods. Conclusions: In lung SBRT treatment, due to fraction reduction and high level of dose per fraction, ANOVA was able to offset the effect of random factors in systematic errors, reducing the PTV margins and volumes. However, no distinct dose distribution improvement was founded in target volume and organs at risk. 展开更多
关键词 SBRT KV-CBCT PTV margin SETUP errors DVH
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Optimal error estimates for Fourier spectral approximation of the generalized KdV equation
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作者 邓镇国 马和平 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2009年第1期29-38,共10页
A Fourier spectral method for the generalized Korteweg-de Vries equation with periodic boundary conditions is analyzed, and a corresponding optimal error estimate in L^2-norm is obtained. It improves the result presen... A Fourier spectral method for the generalized Korteweg-de Vries equation with periodic boundary conditions is analyzed, and a corresponding optimal error estimate in L^2-norm is obtained. It improves the result presented by Maday and Quarteroni. A modified Fourier pseudospectral method is also presented, with the same convergence properties as the Fourier spectral method. 展开更多
关键词 Fourier spectral method modified Fourier pseudospectral method gener-alized Korteweg-de Vries equation error estimate
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Error Estimates for the Difference Method to System of Ordinary Differential Equations with Boundary Layer
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作者 Ilhame Amirali 《Journal of Applied Mathematics and Physics》 2013年第5期79-84,共6页
This work deals with the numerical solution of singular perturbation system of ordinary differential equations with boundary layer. For the numerical solution of this problem fitted finite difference scheme on a unifo... This work deals with the numerical solution of singular perturbation system of ordinary differential equations with boundary layer. For the numerical solution of this problem fitted finite difference scheme on a uniform mesh is constructed and analyzed. The uniform error estimates for the approximate solution are obtained. 展开更多
关键词 SINGULAR PERTURBATION Linear System Difference Scheme UNIFORM Convergence error estimateS
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Error Estimate of the Fourier Collocation Method for the Benjamin-Ono Equation
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作者 Zhenguo Deng Heping Ma 《Numerical Mathematics(Theory,Methods and Applications)》 SCIE 2009年第3期341-352,共12页
In this paper,the Fourier collocation method for solving the generalized Benjamin-Ono equation with periodic boundary conditions is analyzed.Stability of the semi-discrete scheme is proved and error estimate in H^(1/2... In this paper,the Fourier collocation method for solving the generalized Benjamin-Ono equation with periodic boundary conditions is analyzed.Stability of the semi-discrete scheme is proved and error estimate in H^(1/2)-norm is obtained. 展开更多
关键词 Fourier collocation Benjamin-Ono equation error estimate.
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Optimal Error Estimates of the Crank-Nicolson Scheme for Solving a Kind of Decoupled FBSDEs
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作者 Zhe Wang Yang Li 《Journal of Applied Mathematics and Physics》 2018年第2期338-346,共9页
In this paper, under weak conditions, we theoretically prove the second-order convergence rate of the Crank-Nicolson scheme for solving a kind of decoupled forward-backward stochastic differential equations.
关键词 FORWARD BACKWARD Stochastic Differential Equations SECOND-ORDER Scheme error estimate Trapezoidal RULE
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THE APPLICATION OF RANDOM METRIC SPACE IN ERROR ESTIMATE
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作者 Zhu Linhu Yang Yali(Faculty of Engineering,The Air Force Engincering University,Xi’an 710038,PRC) 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2000年第S1期129-131,共3页
Throughout this paper,let(Ω,ι,μ)be a probability space,D the collection of allleft-continuous distribution functions,and D^+={F(0)=0|F∈D},and L(Ω)the collec-tion of all random variables which is a.s.finite on Ω,... Throughout this paper,let(Ω,ι,μ)be a probability space,D the collection of allleft-continuous distribution functions,and D^+={F(0)=0|F∈D},and L(Ω)the collec-tion of all random variables which is a.s.finite on Ω,and L^+={ξ≥0 a.s.|ξ∈L(Ω)}.For random metric (normed) spaces,see [1]or[2].Theorem 1 Let(M,d)be a complete metric space f:M→M,a contract mappingwith contract coefficient α∈[0,1),L(Ω,m)the collection of all M-valued random vari- 展开更多
关键词 In the APPLICATION of RANDOM METRIC SPACE IN 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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A New Method for Identifying the Model Error of Adjust ment System 被引量:3
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作者 TAO Benzao ZHANG Chaoyu 《Geo-Spatial Information Science》 2005年第3期189-192,共4页
Some theory problems affecting parameter estimation are discussed in this paper. Influence and transformation between errors of stochastic and functional models is pointed out as well. For choosing the best adjustment... Some theory problems affecting parameter estimation are discussed in this paper. Influence and transformation between errors of stochastic and functional models is pointed out as well. For choosing the best adjustment model, a formula, which is different from the literatures existing methods, for estimating and identifying the model error, is proposed. On the basis of the proposed formula, an effective approach of selecting the best model of adjustment system is given. 展开更多
关键词 adjustment model model error model error estimation model error identification
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Using self-location to calibrate the errors of observer positions for source localization 被引量:2
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作者 Wanchun Li Wanyi Zhang Liping Li 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第2期194-202,共9页
The uncertainty of observers' positions can lead to significantly degrading in source localization accuracy. This pa-per proposes a method of using self-location for calibrating the positions of observer stations in ... The uncertainty of observers' positions can lead to significantly degrading in source localization accuracy. This pa-per proposes a method of using self-location for calibrating the positions of observer stations in source localization to reduce the errors of the observer positions and improve the accuracy of the source localization. The relative distance measurements of the two coordinative observers are used for the linear minimum mean square error (LMMSE) estimator. The results of computer si-mulations prove the feasibility and effectiveness of the proposed method. With the general estimation errors of observers' positions, the MSE of the source localization with self-location calibration, which is significantly lower than that without self-location calibra-tion, is approximating to the Cramer-Rao lower bound (CRLB). 展开更多
关键词 self-location errors of the observer positions linearminimum mean square error (LMMSE) estimator accuracy of thesource localization Cramer-Rao lower bound (CRLB).
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Application of an Error Statistics Estimation Method to the PSAS Forecast Error Covariance Model 被引量:1
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作者 Runhua YANG Jing GUO Lars Peter RIISHФJGAARD 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2006年第1期33-44,共12页
In atmospheric data assimilation systems, the forecast error covariance model is an important component. However, the paralneters required by a forecast error covariance model are difficult to obtain due to the absenc... In atmospheric data assimilation systems, the forecast error covariance model is an important component. However, the paralneters required by a forecast error covariance model are difficult to obtain due to the absence of the truth. This study applies an error statistics estimation method to the Pfiysical-space Statistical Analysis System (PSAS) height-wind forecast error covariance model. This method consists of two components: the first component computes the error statistics by using the National Meteorological Center (NMC) method, which is a lagged-forecast difference approach, within the framework of the PSAS height-wind forecast error covariance model; the second obtains a calibration formula to rescale the error standard deviations provided by the NMC method. The calibration is against the error statistics estimated by using a maximum-likelihood estimation (MLE) with rawindsonde height observed-minus-forecast residuals. A complete set of formulas for estimating the error statistics and for the calibration is applied to a one-month-long dataset generated by a general circulation model of the Global Model and Assimilation Office (GMAO), NASA. There is a clear constant relationship between the error statistics estimates of the NMC-method and MLE. The final product provides a full set of 6-hour error statistics required by the PSAS height-wind forecast error covariance model over the globe. The features of these error statistics are examined and discussed. 展开更多
关键词 forecast error statistics estimation data analysis forecast error covariance model
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THE ANGLE ERROR ESTIMATE METHOD IN THE WIDE SWATH SAR BASING ON MULTI-RECEIVER 被引量:1
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作者 Wang Xiaoqing Zhu Minhui Sheng Xinqing 《Journal of Electronics(China)》 2006年第3期374-378,共5页
The wide-swath method based on multi-receiver is a novel and highly accurate wide-swath method, which requires a very precise view angle. The estimated angle has error because of the atmosphere refraction, angle error... The wide-swath method based on multi-receiver is a novel and highly accurate wide-swath method, which requires a very precise view angle. The estimated angle has error because of the atmosphere refraction, angle error of view and target height. A method is proposed in this paper to estimate the angle error from the return signal. The method makes use of the relationship between the view angle error and the signal correlation of the subswaths to estimate the angle error. The precision of this method is analyzed by the law of great number and it turns out to be in direct proportion to the root square number of averaging. The simulation result is given and the angle precision is 0.025°. 展开更多
关键词 Synthetic Aperture Radar (SAR) Multi-receiver Angle error estimation
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PERFORMANCE OF THE ZERO FORCING PRECODING MIMO BROADCAST SYSTEMS WITH CHANNEL ESTIMATION ERRORS 被引量:1
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作者 Wang Jing Liu Zhanli Wang Yan You Xiaohu 《Journal of Electronics(China)》 2007年第4期490-495,共6页
In this paper, the effect of channel estimation errors upon the Zero Forcing (ZF) precoding Multiple Input Multiple Output Broadcast (MIMO BC) systems was studied. Based on the two kinds of Gaussian estimation error m... In this paper, the effect of channel estimation errors upon the Zero Forcing (ZF) precoding Multiple Input Multiple Output Broadcast (MIMO BC) systems was studied. Based on the two kinds of Gaussian estimation error models, the performance analysis is conducted under different power allocation strategies. Analysis and simulation show that if the covariance of channel estimation errors is independent of the received Signal to Noise Ratio (SNR), imperfect channel knowledge deteriorates the sum capacity and the Bit Error Rate (BER) performance severely. However, under the situation of orthogonal training and the Minimum Mean Square Error (MMSE) channel estimation, the sum ca- pacity and BER performance are consistent with those of the perfect Channel State Information (CSI) with only a performance degradation. 展开更多
关键词 Zero Forcing (ZF) Multiple Input Multiple Output BroadCast (MIMO BC) system Channel estimation errors Sum capacity
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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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