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A Radial Basis Function Method with Improved Accuracy for Fourth Order Boundary Value Problems
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作者 Scott A. Sarra Derek Musgrave +1 位作者 Marcus Stone Joseph I. Powell 《Journal of Applied Mathematics and Physics》 2024年第7期2559-2573,共15页
Accurately approximating higher order derivatives is an inherently difficult problem. It is shown that a random variable shape parameter strategy can improve the accuracy of approximating higher order derivatives with... Accurately approximating higher order derivatives is an inherently difficult problem. It is shown that a random variable shape parameter strategy can improve the accuracy of approximating higher order derivatives with Radial Basis Function methods. The method is used to solve fourth order boundary value problems. The use and location of ghost points are examined in order to enforce the extra boundary conditions that are necessary to make a fourth-order problem well posed. The use of ghost points versus solving an overdetermined linear system via least squares is studied. For a general fourth-order boundary value problem, the recommended approach is to either use one of two novel sets of ghost centers introduced here or else to use a least squares approach. When using either ghost centers or least squares, the random variable shape parameter strategy results in significantly better accuracy than when a constant shape parameter is used. 展开更多
关键词 Numerical Partial Differential Equations Boundary Value problems Radial Basis function Methods Ghost Points Variable Shape Parameter Least Squares
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ASYMPTOTIC BEHAVIOUR OF EIGENVALUES FOR THE DISCONTINUOUS BOUNDARY-VALUE PROBLEM WITH FUNCTIONAL-TRANSMISSION CONDITIONS 被引量:11
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作者 O.Sh.Mukhtarov Department of Mathematics, Science and Arts Faculty, Gaziosmanpasa University, Tokat, TurkeyMustafa Kandemir Department of Mathematics, Faculty of A mas y a Education, Ondokuz Mayis University, Amasya, Turkey 《Acta Mathematica Scientia》 SCIE CSCD 2002年第3期335-345,共11页
In this study, the boundary-value problem with eigenvalue parameter generated by the differential equation with discontinuous coefficients and boundary conditions which contains not only endpoints of the considered in... In this study, the boundary-value problem with eigenvalue parameter generated by the differential equation with discontinuous coefficients and boundary conditions which contains not only endpoints of the considered interval, but also point of discontinuity and linear functionals is investigated. So, the problem is not pure boundary-value. The authors single out a class of linear functionals and find simple algebraic conditions on coefficients, which garantee the existence of infinit number eigenvalues. Also the asymptotic formulas for eigenvalues are found. 展开更多
关键词 Asymptotic behaviour of eigenvalues boundary-value problems functional-conditions discontinuous coefficients
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ON RIEMANN BOUNDARY VALUE PROBLEM FOR POLYANALYTIC FUNCTIONS ON THE REAL AXIS 被引量:9
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作者 汪玉峰 杜金元 《Acta Mathematica Scientia》 SCIE CSCD 2004年第4期663-671,共9页
In this article, Riemann boundary value problem with different factors for polyanalytic functions on the real axis is studied. The expression of solution and sufficient and necessary condition for solvability of the n... In this article, Riemann boundary value problem with different factors for polyanalytic functions on the real axis is studied. The expression of solution and sufficient and necessary condition for solvability of the non-homogeneous Riemann boundary value problem are obtained. 展开更多
关键词 Polyanalytic function Riemann boundary value problem
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THE HILBERT BOUNDARY VALUE PROBLEM FOR GENERALIZED ANALYTIC FUNCTIONS IN CLIFFORD ANALYSIS 被引量:2
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作者 司中伟 杜金元 《Acta Mathematica Scientia》 SCIE CSCD 2013年第2期393-403,共11页
Let R0,n be the real Clifford algebra generated by e1, e2,... , en satisfying eiej+ejei=-2δij,i,j=1,2…,ne0 is the unit element.Let Ω be an open set. A function f is called left generalized analytic in ft if f sati... Let R0,n be the real Clifford algebra generated by e1, e2,... , en satisfying eiej+ejei=-2δij,i,j=1,2…,ne0 is the unit element.Let Ω be an open set. A function f is called left generalized analytic in ft if f satisfies the equation Lf=0,where ……qi 〉0, i =-, 1, - ……, n. In this article, we first give the kernel function for the generalized analytic function. Further, the Hilbert boundary value problem for generalized analytic functions in Rn+1 will be investigated. 展开更多
关键词 Generalized analytic function Hilbert boundary value problem H^u function
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On the Variational Problems of the Functionals with Derivatives of Higher Orders and Undetermined Boundary 被引量:1
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作者 老大中 谈天民 《Journal of Beijing Institute of Technology》 EI CAS 2007年第1期116-121,共6页
According to the necessary condition of the functional taking the extremum, that is its first variation is equal to zero, the variational problems of the functionals for the undetermined boundary in the calculus of va... According to the necessary condition of the functional taking the extremum, that is its first variation is equal to zero, the variational problems of the functionals for the undetermined boundary in the calculus of variations are researched, the functionals depend on single argument, arbitrary unknown functions and their derivatives of higher orders. A new view point is posed and demonstrated, i.e. when the first variation of the functional is equal to zero, all the variational terms are not independent to each other, and at least one of them is equal to zero. Some theorems and corollaries of the variational problems of the functionals are obtained. 展开更多
关键词 calculus of variations functionAL variational problems derivatives of higher orders undetermined boundary
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Analytical solution of axisymmetric contact problem about indentation of a circular indenter into a soft functionally graded elastic layer 被引量:2
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作者 Sergey Volkov Sergey Aizikovich +1 位作者 Yue-Sheng Wang Igor Fedotov 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2013年第2期196-201,共6页
The paper addresses a contact problem of the theory of elasticity,i.e.,the penetration of a circular indenter with a flat base into a soft functionally graded elastic layer.The elastic properties of a functionally gra... The paper addresses a contact problem of the theory of elasticity,i.e.,the penetration of a circular indenter with a flat base into a soft functionally graded elastic layer.The elastic properties of a functionally graded layer arbitrarily vary with depth,and the foundation is assumed to be elastic,yet much harder than a layer.Approximated analytical solution is constructed,and it is shown that the solutions are asymptotically exact both for large and small values of characteristic dimensionless geometrical parameter of the problem.Numerical examples are analyzed for the cases of monotonic and nonmonotonic variations of elastic properties.Numerical results for the case of homogeneous layer are compared with the results for nondeformable foundation. 展开更多
关键词 Contact problems·Indentation·functionally graded layer
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PARAMETER IDENTIFICATION PROBLEM OF THE FRACTAL INTERPOLATION FUNCTIONS 被引量:5
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作者 阮火军 沙震 苏维宜 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2003年第2期205-213,共9页
Parameter identification problem is one of essential problem in order to model effectively experimental data by fractal interpolation function.In this paper,we first present an example to explain a relationship betwee... Parameter identification problem is one of essential problem in order to model effectively experimental data by fractal interpolation function.In this paper,we first present an example to explain a relationship between iteration procedure and fractal function.Then we discuss conditions that vertical scaling factors must obey in one typical case. 展开更多
关键词 分形插值函数 参数鉴定 吸引子 垂直定标因数
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Fekete-Szeg Problems for Certain Classes of Meromorphic Functions Using q-Derivative Operator 被引量:1
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作者 Huo TANG H.M.ZAYED +1 位作者 A.O.MOSTAFA M.K.AOUF 《Journal of Mathematical Research with Applications》 CSCD 2018年第3期236-246,共11页
In this paper, we introduce two subclasses Eq *(φ) and ∑*q,a(φ) of meromorphic functions f(z) for which qzDqf(z)/f(z)〈φ (z) and-(1-a/q)qzDqf(z)+azqDq[zDqf(z)]/(1-a/q)f(z)-azDqf(z)〈φ(... In this paper, we introduce two subclasses Eq *(φ) and ∑*q,a(φ) of meromorphic functions f(z) for which qzDqf(z)/f(z)〈φ (z) and-(1-a/q)qzDqf(z)+azqDq[zDqf(z)]/(1-a/q)f(z)-azDqf(z)〈φ(z),a ∈ C/(0,1],0〈q〈1, respectively. Sharp bounds for the Fekete-Szeg5 functional lal-tta21 of the above classes are obtained. Also, we consider some applications of the results obtained to functions defined by q-Bessel function. 展开更多
关键词 analytic function meromorphic function Fekete-Szego problem q-derivative operator q-Bessel function
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OPTIMALITY CONDITIONS AND DUALITY RESULTS FOR NONSMOOTH VECTOR OPTIMIZATION PROBLEMS WITH THE MULTIPLE INTERVAL-VALUED OBJECTIVE FUNCTION 被引量:5
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作者 Tadeusz ANTCZAK 《Acta Mathematica Scientia》 SCIE CSCD 2017年第4期1133-1150,共18页
In this paper, both Fritz John and Karush-Kuhn-Tucker necessary optimality conditions are established for a (weakly) LU-efficient solution in the considered nonsmooth multiobjective programming problem with the mult... In this paper, both Fritz John and Karush-Kuhn-Tucker necessary optimality conditions are established for a (weakly) LU-efficient solution in the considered nonsmooth multiobjective programming problem with the multiple interval-objective function. Further, the sufficient optimality conditions for a (weakly) LU-efficient solution and several duality results in Mond-Weir sense are proved under assumptions that the functions constituting the considered nondifferentiable multiobjective programming problem with the multiple interval- objective function are convex. 展开更多
关键词 nonsmooth multiobjective programming problem with the multiple interval- objective function Fritz John necessary optimality conditions Karush-Kuhn- Tucker necessary optimality conditions (weakly) LU-efficient solution Mond- Weir duality
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RIEMANN BOUNDARY VALUE PROBLEMS FOR SOME K-REGULAR FUNCTIONS IN CLIFFORD ANALYSIS 被引量:3
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作者 姜乐 杜金元 《Acta Mathematica Scientia》 SCIE CSCD 2012年第5期2029-2049,共21页
In this paper,we study the R m(m〉0) Riemann boundary value problems for regular functions,harmonic functions and bi-harmonic functions with values in a universal clifford algebra C(Vn,n).By using Plemelj formula,... In this paper,we study the R m(m〉0) Riemann boundary value problems for regular functions,harmonic functions and bi-harmonic functions with values in a universal clifford algebra C(Vn,n).By using Plemelj formula,we get the solutions of R m(m〉0) Riemann boundary value problems for regular functions.Then transforming the Riemann boundary value problems for harmonic functions and bi-harmonic functions into the Riemann boundary value problems for regular functions,we obtain the solutions of R m(m〉0) Riemann boundary value problems for harmonic functions and bi-harmonic functions. 展开更多
关键词 Riemann boundary value problem harmonic function bi-harmonic function Plemelj formula
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Do Functional Problems and Neighborhood Disturbances in and around the Home Trigger Injuries?
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作者 Koustuv Dalal Charli Eriksson 《Health》 2014年第11期1085-1091,共7页
The study has tried to identify whether poor self-rated health and home and neighbourhood environmental problems trigger injuries. The study used data from the Life & Health year 2008 survey, a postal questionnair... The study has tried to identify whether poor self-rated health and home and neighbourhood environmental problems trigger injuries. The study used data from the Life & Health year 2008 survey, a postal questionnaire administered by Statistics Sweden in five administrative regions in central Sweden (Uppsala, S?dermanland, ?rebro, Varmland and V?stmanland). A random sample of 1,060,032 respondents aged 18 - 79 years had participated in the study. ?rebro and Varmland region had the highest proportions of injuries. People at their age between 18 to 24 years—males—tobacco and alcohol addicted had the highest proportions of injuries. Environmental factors such as disturbances in and around home had emerged as major triggering factors for injuries. Physical functional problems such as problem of buying own food, cooking, dressing-up and walking had been emerged as very strong predicting factors of injuries. Policy makers in Sweden could identify the poor neighborhood, disturb living condition through the housing companies and the cooperative housing societies to control injuries and promote safety. 展开更多
关键词 UNINTENTIONAL INJURIES functionAL problemS and LIVELIHOOD Disturbances Sweden
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Mixed Finite Element Formats of any Order Based on Bubble Functions for Stationary Stokes Problem 被引量:1
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作者 CAO Ji-wei LIU Ming-fang CHEN Shao-chun 《Chinese Quarterly Journal of Mathematics》 2016年第1期87-95,共9页
Mixed element formats of any order based on bubble functions for the stationary Stokes problem are derived in triangular and tetrahedral meshes and the convergence of these formats are proved.
关键词 mixed finite element method bubble function the stationary Stokes problem
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Solutions of Green's function for Lamb's problem of a two-phase saturated medium 被引量:3
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作者 Boyang Ding,and Jun Chen College of Civil Engineering and Architecture,Zhejiang University of Technology,Hangzhou 310014,China 《Theoretical & Applied Mechanics Letters》 CAS 2011年第5期55-59,共5页
The solutions of Green’s function are significant for simplification of problem on a two-phase saturated medium.Using transformation of axisymmetric cylindrical coordinate and Sommerfeld’s integral,superposition of ... The solutions of Green’s function are significant for simplification of problem on a two-phase saturated medium.Using transformation of axisymmetric cylindrical coordinate and Sommerfeld’s integral,superposition of the influence field on a free surface,authors obtained the solutions of a two-phase saturated medium subjected to a concentrated force on the semi-space. 展开更多
关键词 Green's function two-phase saturated medium Lamb's problem
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EXTENSION OF SMOOTHING FUNCTIONS TO SYMMETRIC CONE COMPLEMENTARITY PROBLEMS 被引量:2
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作者 Liu Yongjin Zhang Liwei Liu Meijiao 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2007年第2期245-252,共8页
The paper uses Euclidean Jordan algebras as a basic tool to extend smoothing functions, which include the Chen-Mangasarian class and the Fischer-Burmeister smoothing functions, to symmetric cone complementarity proble... The paper uses Euclidean Jordan algebras as a basic tool to extend smoothing functions, which include the Chen-Mangasarian class and the Fischer-Burmeister smoothing functions, to symmetric cone complementarity problems. Computable formulas for these functions and their Jacobians are derived. In addition, it is shown that these functions are Lipschitz continuous with respect to parameter # and continuously differentiable on J × J for any μ 〉 0. 展开更多
关键词 symmetric cone complementarity problem smoothing function Euclidean Jordan algebra non-interior continuation method
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Integral Global Minimization of Constrained Problems with Discontinuous Penalty Functions 被引量:1
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作者 吴斌 崔洪泉 郑权 《Journal of Shanghai University(English Edition)》 CAS 2005年第5期385-390,共6页
A class of discontinuous penalty functions was proposed to solve constrained minimization problems with the integral approach to global optimization, m-mean value and v-variance optimality conditions of a constrained ... A class of discontinuous penalty functions was proposed to solve constrained minimization problems with the integral approach to global optimization, m-mean value and v-variance optimality conditions of a constrained and penalized minimization problem were investigated. A nonsequential algorithm was proposed. Numerical examples were given to illustrate the effectiveness of the algorithm. 展开更多
关键词 integral global minimization constrained minimization problems discontinuous penalty functions.
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Comments on “General solutions of plane problem for power function curved cracks”
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作者 陈宜周 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2012年第8期1093-1094,共2页
An error has been found in Ref. [1]. In the case of n = 2, authors of Ref. [1] suggested the following conformal mapping function:
关键词 General solutions of plane problem for power function curved cracks Comments on
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Competitive analysis of price online inventory problem with cost function 被引量:1
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作者 HAN Shu-guang GUO Jiu-ling +1 位作者 ZHANG Lu-ping HU Jue-liang 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2017年第4期493-502,共10页
In this paper,a new price is given to the online decision maker at the beginning of each day.The trader must decide how many items to purchase according to the current price.We present three variants and an online alg... In this paper,a new price is given to the online decision maker at the beginning of each day.The trader must decide how many items to purchase according to the current price.We present three variants and an online algorithm based on cost function.The competitive ratio of the online algorithm is given for each variant,which is a performance measure of an online algorithm.More importantly,we show that the online algorithm is optimal. 展开更多
关键词 inventory problem price online cost function competitive analysis
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Solving frictional contact problems by two aggregate-function-based algorithms
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作者 Suyan He Hongwu Zhang Xingsi Li 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2005年第5期467-471,共5页
Three dimensional frictional contact problems are formulated as linear complementarity problems based on the parametric variational principle. Two aggregate-functionbased algorithms for solving complementarity problem... Three dimensional frictional contact problems are formulated as linear complementarity problems based on the parametric variational principle. Two aggregate-functionbased algorithms for solving complementarity problems are proposed. One is called the self-adjusting interior point algorithm, the other is called the aggregate function smoothing algorithm. Numerical experiment shows the efficiency of the proposed two algorithms. 展开更多
关键词 Frictional contact problem. Linear complementarity problem .Aggregate function ~ Interior pointalgorithm ~ Smoothing algorithm
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EXISTENCE OF POSITIVE SOLUTIONS FOR p-LAPLACIAN SINGULAR BOUNDARY VALUE PROBLEMS OF FUNCTIONAL DIFFERENTIAL EQUATION 被引量:6
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作者 SongChangxiu WengPeixuan 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2005年第1期51-58,共8页
In this paper,the boundary value problems of p-Laplacian functional differential equation are studied.By using a fixed point theorem in cones,some criteria for the existence of positive solutions are given.
关键词 p-Laplacian operator functional differential equation boundary value problem positive solution fixed point theorem in cones.
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Logarithm of a Function, a Well-Posed Inverse Problem
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作者 Silvia Reyes Mora Víctor A. Cruz Barriguete Denisse Guzmán Aguilar 《American Journal of Computational Mathematics》 2014年第1期1-5,共5页
It poses the inverse problem that consists in finding the logarithm of a function. It shows that when the function is holomorphic in a simply connected domain , the solution at the inverse problem exists and is unique... It poses the inverse problem that consists in finding the logarithm of a function. It shows that when the function is holomorphic in a simply connected domain , the solution at the inverse problem exists and is unique if a branch of the logarithm is fixed. In addition, it’s demonstrated that when the function is continuous in a domain , where is Hausdorff space and connected by paths. The solution of the problem exists and is unique if a branch of the logarithm is fixed and is stable;for what in this case, the inverse problem turns out to be well-posed. 展开更多
关键词 LOGARITHM function INVERSE problem STABILITY
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