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RECURRENT NEURAL NETWORK MODEL BASED ON PROJECTIVE OPERATOR AND ITS APPLICATION TO OPTIMIZATION PROBLEMS
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作者 马儒宁 陈天平 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第4期543-554,共12页
The recurrent neural network (RNN) model based on projective operator was studied. Different from the former study, the value region of projective operator in the neural network in this paper is a general closed con... The recurrent neural network (RNN) model based on projective operator was studied. Different from the former study, the value region of projective operator in the neural network in this paper is a general closed convex subset of n-dimensional Euclidean space and it is not a compact convex set in general, that is, the value region of projective operator is probably unbounded. It was proved that the network has a global solution and its solution trajectory converges to some equilibrium set whenever objective function satisfies some conditions. After that, the model was applied to continuously differentiable optimization and nonlinear or implicit complementarity problems. In addition, simulation experiments confirm the efficiency of the RNN. 展开更多
关键词 recurrent neural network model projective operator global convergence OPTIMIZATION complementarity problems
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Accelerated Primal-Dual Projection Neurodynamic Approach With Time Scaling for Linear and Set Constrained Convex Optimization Problems
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作者 You Zhao Xing He +1 位作者 Mingliang Zhou Tingwen Huang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第6期1485-1498,共14页
The Nesterov accelerated dynamical approach serves as an essential tool for addressing convex optimization problems with accelerated convergence rates.Most previous studies in this field have primarily concentrated on... The Nesterov accelerated dynamical approach serves as an essential tool for addressing convex optimization problems with accelerated convergence rates.Most previous studies in this field have primarily concentrated on unconstrained smooth con-vex optimization problems.In this paper,on the basis of primal-dual dynamical approach,Nesterov accelerated dynamical approach,projection operator and directional gradient,we present two accelerated primal-dual projection neurodynamic approaches with time scaling to address convex optimization problems with smooth and nonsmooth objective functions subject to linear and set constraints,which consist of a second-order ODE(ordinary differential equation)or differential conclusion system for the primal variables and a first-order ODE for the dual vari-ables.By satisfying specific conditions for time scaling,we demonstrate that the proposed approaches have a faster conver-gence rate.This only requires assuming convexity of the objective function.We validate the effectiveness of our proposed two accel-erated primal-dual projection neurodynamic approaches through numerical experiments. 展开更多
关键词 Accelerated projection neurodynamic approach lin-ear and set constraints projection operators smooth and nonsmooth convex optimization time scaling.
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SINGULAR INTEGRAL EQUATIONS WITHCOMPLEX TRANSLATIONS 被引量:1
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作者 杜金元 胡继承 《Acta Mathematica Scientia》 SCIE CSCD 1999年第4期469-480,共12页
In this paper, a class of singular integral equations with complex translations is discussed. By using the Plemelj projection method the authors reduce them to the boundary value problem of analytic functions in A(+)(... In this paper, a class of singular integral equations with complex translations is discussed. By using the Plemelj projection method the authors reduce them to the boundary value problem of analytic functions in A(+)(H) over cap(0) with upper translation and the boundary value problem of analytic functions in A-(H) over cap(0) with lower translation, which are solved here. 展开更多
关键词 singular integral equation singular integral operator singular projection operator upper translation lower translation
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Arnoldi Projection Fractional Tikhonov for Large Scale Ill-Posed Problems 被引量:1
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作者 Wang Zhengsheng Mu Liming +1 位作者 Liu Rongrong Xu Guili 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2018年第3期395-402,共8页
It is well known that Tikhonov regularization in standard form may determine approximate solutions that are too smooth for ill-posed problems,so fractional Tikhonov methods have been introduced to remedy this shortcom... It is well known that Tikhonov regularization in standard form may determine approximate solutions that are too smooth for ill-posed problems,so fractional Tikhonov methods have been introduced to remedy this shortcoming.And Tikhonov regularization for large-scale linear ill-posed problems is commonly implemented by determining apartial Arnoldi decomposition of the given matrix.In this paper,we propose a new method to compute an approximate solution of large scale linear discrete ill-posed problems which applies projection fractional Tikhonov regularization in Krylov subspace via Arnoldi process.The projection fractional Tikhonov regularization combines the fractional matrices and orthogonal projection operators.A suitable value of the regularization parameter is determined by the discrepancy principle.Numerical examples with application to image restoration are carried out to examine that the performance of the method. 展开更多
关键词 ill-posed problems fractional matrix Tikhonov regularization orthogonal projection operator image restoration
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Non-Markovian dynamics of a qubit in a reservoir: different solutions of non-Markovian master equation 被引量:1
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作者 丁邦福 王小云 +2 位作者 唐艳芳 米贤武 赵鹤平 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第6期25-29,共5页
We present a non-Markovian master equation for a qubit interacting with a general reservoir, which is derived according to the Nakajima-Zwanzig and the time convolutionless projection operator technique. The non-Marko... We present a non-Markovian master equation for a qubit interacting with a general reservoir, which is derived according to the Nakajima-Zwanzig and the time convolutionless projection operator technique. The non-Markovian solutions and Markovian solution of dynamical decay of a qubit are compared. The results indicate the validity of non-Markovian approach in different coupling regimes and also show that the Markovian master equation may not precisely describe the dynamics of an open quantum system in some situation. The non-Markovian solutions may be effective for many qubits independently interacting with the heated reservoirs. 展开更多
关键词 Nakajima-Zwanzig and time convolutionless projection operator technique non- Markovian solutions Markovian solutions correlation function QUBIT
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ERROR ESTIMATE FOR INFLUENCE OF MODEL REDUCTION OF NONLINEAR DISSIPATIVE AUTONOMOUS DYNAMICAL SYSTEM ON LONG-TERM BEHAVIOURS
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作者 张家忠 刘雁 陈党民 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2005年第7期938-943,共6页
From viewpoint of nonlinear dynamics, the model reduction and its influence on the long-term behaviours of a class of nonlinear dissipative autonomous dynamical system with higher dimension are investigated theoretica... From viewpoint of nonlinear dynamics, the model reduction and its influence on the long-term behaviours of a class of nonlinear dissipative autonomous dynamical system with higher dimension are investigated theoretically under some assumptions. The system is analyzed in the state space with an introduction of a distance definition which can be used to describe the distance between the full system and the reduced system, and the solution of the full system is then projected onto the complete space spanned by the eigenvectors of the linear operator of the governing equations. As a result, the influence of mode series truncation on the long-term behaviours and the error estimate are derived, showing that the error is dependent on the first products of frequencies and damping ratios in the subspace spanned by the eigenvectors with higher modal damping. Furthermore, the fundamental understanding for the topological change of the solution due to the application of different model reduction is interpreted in a mathematically precise way, using the qualitative theory of nonlinear dynamics. 展开更多
关键词 nonlinear dynamical system dissipative system projection operator long-term behaviour
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Non-Markovian dynamics of two non-coupled qubits interacting with two separate reservoirs with different spectral densities
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作者 王小云 丁邦福 赵鹤平 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第4期128-132,共5页
The dynamics of two non-coupled qubits independently interacting with their reservoirs is solved by the time convolutionless projection operator method. We study two-qubit quantum correlation dynamics for two differen... The dynamics of two non-coupled qubits independently interacting with their reservoirs is solved by the time convolutionless projection operator method. We study two-qubit quantum correlation dynamics for two different types of spectral densities, which are a Lorentzian distribution and an Ohmic spectral density with a Lorentzian–Drude cutoff function. For two qubits initially prepared in the initial Bell state, quantum discord can keep longer time and reach larger values in nonMarkovian reservoirs for the first spectral distribution or by reducing the cutoff frequency for the second case. For the initial Bell-like state, the dynamic behaviors of quantum discord and entanglement are compared. The results show that a long time of quantum correlation can be obtained by adjusting some parameters in experiment and further confirm that the discord can capture quantum correlation in addition to entanglement. 展开更多
关键词 Lorentzian and Ohmic spectral densities the time convolution-less projection operator method non-Markovian and Markovian regime quantum discord and entanglement
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Jilin Tongyu Wind Power Farm 2nd Phase Project put into operation
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《Electricity》 2001年第1期51-51,共1页
关键词 WIND PROJECT Jilin Tongyu Wind Power Farm 2nd Phase Project put into operation
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The Second-Order Differential Equation System with the Feedback Controls for Solving Convex Programming
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作者 Xingxu Chen Li Wang +1 位作者 Juhe Sun Yanhong Yuan 《Open Journal of Applied Sciences》 2022年第6期977-989,共13页
In this paper, we establish the second-order differential equation system with the feedback controls for solving the problem of convex programming. Using Lagrange function and projection operator, the equivalent opera... In this paper, we establish the second-order differential equation system with the feedback controls for solving the problem of convex programming. Using Lagrange function and projection operator, the equivalent operator equations for the convex programming problems under the certain conditions are obtained. Then a second-order differential equation system with the feedback controls is constructed on the basis of operator equation. We prove that any accumulation point of the trajectory of the second-order differential equation system with the feedback controls is a solution to the convex programming problem. In the end, two examples using this differential equation system are solved. The numerical results are reported to verify the effectiveness of the second-order differential equation system with the feedback controls for solving the convex programming problem. 展开更多
关键词 Convex Programming Lagrange Function Projection operator Second-Order Differential Equation
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Research on Safety Risk Assessment Method for Large Scale Field Operation Project
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作者 JIANG Wei-yang ZHAO Man-yun +1 位作者 ZHANG Lian SONG Wei-dong 《International Journal of Plant Engineering and Management》 2016年第2期65-74,共10页
By applying man-machine-environment system engineering theory, safety risks on large scale field operation project have been evaluated in this article. The factors concerning with the man, machine and environment in s... By applying man-machine-environment system engineering theory, safety risks on large scale field operation project have been evaluated in this article. The factors concerning with the man, machine and environment in system were proposed separately. The value for lowest indexs was determined by decision-making of expert group. The weights were calculated based on AHP, and then safety risk assessment in different layers was made. The results show that the assessment method is reasonable, and it is significant for large scale field operation project safety managerment. 展开更多
关键词 large scale field operation project safety risk assessment man-machine-environment system
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Risk Management and Operation Strategies of Chinese Overseas Risk Exploration Projects
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作者 Li Juntin Li Song Wen Zhifeng 《China Oil & Gas》 CAS 2013年第4期41-47,共7页
Currently,the investment of oil and gas industry is still facing an unfavorable environment,in which,instable factors,such as financial crisis,terrorist,religious conflicts and rigorous environmental regulations,keep ... Currently,the investment of oil and gas industry is still facing an unfavorable environment,in which,instable factors,such as financial crisis,terrorist,religious conflicts and rigorous environmental regulations,keep mucking up the business all around the world.Meanwhile,China’s rapid energy consumption growth boosted by a booming economy has put the country to rely heavily on exported oil.It is therefore extremely urgent to expand and diversify petroleum supply channel in consideration of the country’s energy security.As the world’s economy has been slowly recovering from the slump and 展开更多
关键词 HSE Risk Management and Operation Strategies of Chinese Overseas Risk Exploration Projects
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West-East Gas Project Operational This Year
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《Journal of Natural Gas Chemistry》 CAS CSCD 2004年第4期248-248,共1页
China’s massive project to transfer natural gas from the Tarim Basin of Xinjiang Uygur autonomous region all the way to the coastal metropolis of Shanghai in the east will go into commercial operation on Dec. 30, acc... China’s massive project to transfer natural gas from the Tarim Basin of Xinjiang Uygur autonomous region all the way to the coastal metropolis of Shanghai in the east will go into commercial operation on Dec. 30, according to the National Development and Reform Commission (NDRC). 展开更多
关键词 PROJECT West-East Gas Project Operational This Year
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The Connection Between the Metric and Generalized Projection Operators in Banach Spaces 被引量:3
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作者 Yakov ALBER Jin Lu LI 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2007年第6期1109-1120,共12页
In this paper we study the connection between the metric projection operator PK : B →K, where B is a reflexive Banach space with dual space B^* and K is a non-empty closed convex subset of B, and the generalized pr... In this paper we study the connection between the metric projection operator PK : B →K, where B is a reflexive Banach space with dual space B^* and K is a non-empty closed convex subset of B, and the generalized projection operators ∏K : B → K and πK : B^* → K. We also present some results in non-reflexive Banach spaces. 展开更多
关键词 Banach spaces normalized duality mappings metric and generalized projection operators variational inequalities minimization problems closed and convex subsets and cones
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Some Applications of Projection Operators in Wavelets 被引量:5
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作者 Han Bin Institute of Mathematics Academia Sinica Beijing,100080 China 《Acta Mathematica Sinica,English Series》 SCIE CSCD 1995年第1期105-112,共8页
By rewriting the projection operator P<sub>0</sub> in wavelets in another formula,we obtain a characterization of dim J<sub>V</sub><sub>0</sub>(x)where V<sub>0</sub> i... By rewriting the projection operator P<sub>0</sub> in wavelets in another formula,we obtain a characterization of dim J<sub>V</sub><sub>0</sub>(x)where V<sub>0</sub> is a Γ-shift-invariant subspace of L<sup>2</sup>(R<sup>n</sup>)derived from a dual wavelet basis and prove that there does not exist a wavelet function ψ ∈ L<sup>2</sup>(R)such that (?)has compact support and ∪<sub>k</sub>∈ZZ(supp■+4πk)=R up to a zero subset of R. 展开更多
关键词 Some Applications of Projection operators in Wavelets
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Decomposition of Molecular Motions into Translational, Rotational, and Intramolecular Parts by a Projection Operator Technique
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作者 F.Y.Hansen H.Taub 《Communications in Computational Physics》 SCIE 2009年第7期231-246,共16页
The motion of the atoms in a molecule may be described as a superposition of translational motion of the molecular center-of-mass,rotational motion about the principal molecular axes,and an intramolecular motion that ... The motion of the atoms in a molecule may be described as a superposition of translational motion of the molecular center-of-mass,rotational motion about the principal molecular axes,and an intramolecular motion that may be associated with vibrations and librations as well as molecular conformational changes.We have constructed projection operators that use the atomic coordinates and velocities at any two times,t=0 and a later time t,to determine the molecular center-of-mass,rotational,and intramolecular motions in a molecular dynamics simulation.This model-independent technique facilitates characterization of the atomic motions within a system of complex molecules and is important for the interpretation of experiments that rely on time correlation functions of atomic and molecular positions and velocities.The application of the projection operator technique is illustrated for the inelastic neutron scattering functions and for the translational and rotational velocity autocorrelation functions. 展开更多
关键词 Molecular dynamics projection operator correlation functions scattering functions translational motion rotational motion intramolecular motion
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SUPERAPPROXIMATION PROPERTIES OF THE INTERPOLATION OPERATOR OF PROJECTION TYPE AND APPLICATIONS 被引量:1
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作者 Tie Zhang Yan-ping Lin R.J.Tait 《Journal of Computational Mathematics》 SCIE EI CSCD 2002年第3期277-288,共12页
Presents information on a study which analyzed superapproximation properties for the interpolation operator of projection type on two-dimensional domain. Discussion on the interpolation operator of projection type and... Presents information on a study which analyzed superapproximation properties for the interpolation operator of projection type on two-dimensional domain. Discussion on the interpolation operator of projection type and its superapproximation properties; Superconvergence of Ritz projection; Proof and applications of the superconveregence of Ritz-Volterra projection. 展开更多
关键词 interpolation operator of projection type finite element SUPERCONVERGENCE
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Distributed accelerated primal-dual neurodynamic approaches for resource allocation problem
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作者 ZHAO You HE Xing +1 位作者 YU JunZhi HUANG TingWen 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2023年第12期3639-3650,共12页
This paper investigates two distributed accelerated primal-dual neurodynamic approaches over undirected connected graphs for resource allocation problems(RAP)where the objective functions are generally convex.With the... This paper investigates two distributed accelerated primal-dual neurodynamic approaches over undirected connected graphs for resource allocation problems(RAP)where the objective functions are generally convex.With the help of projection operators,a primal-dual framework,and Nesterov's accelerated method,we first design a distributed accelerated primal-dual projection neurodynamic approach(DAPDP),and its convergence rate of the primal-dual gap is O(1/(t^(2)))by selecting appropriate parameters and initial values.Then,when the local closed convex sets are convex inequalities which have no closed-form solutions of their projection operators,we further propose a distributed accelerated penalty primal-dual neurodynamic approach(DAPPD)on the strength of the penalty method,primal-dual framework,and Nesterov's accelerated method.Based on the above analysis,we prove that DAPPD also has a convergence rate O(1/(t^(2)))of the primal-dual gap.Compared with the distributed dynamical approaches based on the classical primal-dual framework,our proposed distributed accelerated neurodynamic approaches have faster convergence rates.Numerical simulations demonstrate that our proposed neurodynamic approaches are feasible and effective. 展开更多
关键词 accelerated primal-dual neurodynamic approaches RAP projection operators penalty method convergence rate O(1/(t^(2)))
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The hydrological effect between Jingjiang River and Dongting Lake during the initial period of Three Gorges Project operation 被引量:33
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作者 CHANG Jiang LI Jingbao +4 位作者 LU Dianqing ZHU Xiang LU Chengzhi ZHOU Yueyun DENG Chuxiong 《Journal of Geographical Sciences》 SCIE CSCD 2010年第5期771-786,共16页
Based on the measured hydrological data from 1951 to 2008, the chain hydrological effect between Jingjiang River and Dongting Lake is analyzed by comparative method after the Three Gorges Project operation. The result... Based on the measured hydrological data from 1951 to 2008, the chain hydrological effect between Jingjiang River and Dongting Lake is analyzed by comparative method after the Three Gorges Project operation. The result indicates that 1) the scouring amount in Jing- jiang River made up 78.9% of the total from Yichang to Chenglingji, and its average scouring intensity was higher than the latter; 2) the water and sand diversion rates at the three outlets of the Jingjiang River were reduced by 2.33% and 2.78% separately; 3) the proportion of multi-year average runoff and sediment through the three outlets in the total into the Dongting Lake decreased by 7.7% and 24.4% respectively; 4) in Dongting Lake, the speed of sediment accumulation was lowered by 26.7%, in flood season, the runoff amount was 20.2% less than the multi-year average value, leading to seasonal scarcity of water year by year. The former prolonged the lake life, while the latter induced droughts in summer and fall in successive years, shortage of drinking and industrial water, shipping insecurity, as well as ecological problems such as decrease of birds and quick increase of Microtus fortis; 5) The multi-year average values of sediment and flood transporting capacity at the lake outlet were respec- tively increased by 26.6% and 3.7%, the adapt to the new change of the river-lake embankments were protected effectively. Then, to relation, some suggestions were put forward, such as optimizing further operation program of the Three Gorges Reservoir, reexamining the idea of river and lake regulation, and maintaining connection of the river and the lake. 展开更多
关键词 initial period of Three Gorges Project operation silt-discharge relating hydrological effect DongtingLake area
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DOMAIN DECOMPOSITION WITH NONMATCHING GRIDS FOR EXTERIOR TRANSMISSION PROBLEMS VIA FEM AND DTN MAPPING
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作者 Ju-e Yang De-hao Yu 《Journal of Computational Mathematics》 SCIE EI CSCD 2006年第3期323-342,共20页
In this paper, we are concerned with a non-overlapping domain decomposition method (DDM) for exterior transmission problems in the plane. Based on the natural boundary integral operator, we combine the DDM with a Di... In this paper, we are concerned with a non-overlapping domain decomposition method (DDM) for exterior transmission problems in the plane. Based on the natural boundary integral operator, we combine the DDM with a Dirichlet-to-Neumann (DtN) mapping and provide the numerical analysis with nonmatching grids. The weak continuity of the approximation solutions on the interface is imposed by a dual basis multiplier. We show that this multiplier space can generate optimal error estimate and obtain the corresponding rate of convergence. Finally, several numerical examples confirm the theoretical results. 展开更多
关键词 Domain decomposition Nature boundary element Nonmatching grids Weakcontinuity D-N alternating Dual basis Projection operator Error estimate.
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Decomposition and Approximation of Multivariate Functions on the Cube
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作者 Zhi Hua ZHANG 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2013年第1期119-136,共18页
In this paper, we present a decomposition method of multivariate functions. This method shows that any multivariate function f on [0, 1]d is a finite sum of the form ∑jФjψj, where each Фj can be extended to a smoo... In this paper, we present a decomposition method of multivariate functions. This method shows that any multivariate function f on [0, 1]d is a finite sum of the form ∑jФjψj, where each Фj can be extended to a smooth periodic function, each ψj is an algebraic polynomial, and each Фjψj is a product of separated variable type and its smoothness is same as f. Since any smooth periodic function can be approximated well by trigonometric polynomials, using our decomposition method, we find that any smooth multivariate function on [0, 1]d can be approximated well by a combination of algebraic polynomials and trigonometric polynomials. Meanwhile, we give a precise estimate of the approximation error. 展开更多
关键词 Decomposition of multivariate functions approximation of multivariate functions fundamental polynomial projection operator classification of boundary points
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