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Boundedness of Multiplication Operators on α-Bloch Spaces
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作者 GUOJi-dong LOUZeng-jian 《Chinese Quarterly Journal of Mathematics》 CSCD 2004年第2期205-208,共4页
In this note we study and give a full characterization of the boundeness of mul-tiplication operators on α-Bloch spaces.
关键词 multiplication operator a-Bloch space boundeness
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Frictional contact algorithm study on the numerical simulation of large deformations in deep soft rock tunnels 被引量:5
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作者 GUO Hongyun CHEN Xin +2 位作者 HE Manchao XI Shouzhong TANG Juzhen 《Mining Science and Technology》 EI CAS 2010年第4期524-529,共6页
There exist three types of nonlinear problems in large deformation processes of deep softrock engineering, i.e., nonlin- earity caused by material, geometrical and contact boundary. In this paper, the numerical method... There exist three types of nonlinear problems in large deformation processes of deep softrock engineering, i.e., nonlin- earity caused by material, geometrical and contact boundary. In this paper, the numerical method to tackle the nonlinear eontact and large deformation problem in A Software on Large Deformation Analysis for Soft Rock Engineering at Great Depth was presented. In the software, based on Lagrange multiplier method and Coulomb friction law, kinematic constraints on contact boundaries were introduced in functional function, and the finite element equations was established for two incremental large deformation analyses models, polar decomposition model and additive decomposition model. For every incremental loading step, by searching for the contact points in the potential contact interfaces (the excavation boundaries), the Lagrange multipliers, i.e., contact forces are cal- culated iteratively by Gauss-Seidel method, and justified through satisfy the inequalities of static constraint on contact boundaries. With the software, large deformation and frictional contact of a transport roadway were analyzed numerically by the two models. The numerical examples demonstrated the efficiency of the method used in the software. 展开更多
关键词 deep softrock engineering large deformation frictional contact Lagrange multiplier method FEM
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Determination of Natural Frequencies of Multilayered Plates by Mixed Finite Elements
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作者 Roberto S. Carnicer Braian A. Desia Rodolfo A. Schwarz 《Journal of Mechanics Engineering and Automation》 2014年第10期820-827,共8页
Natural frequencies for multilayer plates are calculated by mixed finite element method. The main object of this paper is to use the mixed model for multilayer plates, analyzing each layer as an isolated plate, where ... Natural frequencies for multilayer plates are calculated by mixed finite element method. The main object of this paper is to use the mixed model for multilayer plates, analyzing each layer as an isolated plate, where the continuity of displacements is achieved by Lagrange multipliers (representing static variables). This procedure allows us to work with any model for single plate (so as to ensure the proper behavior of each layer), and the complexity of the multilayer system is avoided by ensuring the condition of displacements by the Lagrange multipliers (static variables). The plate is discretized by finite element modeling based on a primary hybrid model, where the domain is divided by quadrilateral, both for the displacement field and static variables. This mixed element for plates was implemented and several examples of vibrations have been verified successfully by the results obtained by other methods in the literature. 展开更多
关键词 Mixed finite element multilayer plate Lagrange multipliers natural frequencies free vibrations.
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论补数除法(上)
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作者 江璧卿 《齐鲁珠坛》 1997年第5期11-12,共2页
论补数除法(上)江璧卿(编者按:本文是作者提交福建省97年度珠算教育研讨会上讨论的论文,内容主要是关于开发补数除法的构想。内文较长,现分三次连载,以飨读者。)一、什么是补数除法补数除法是以除数的补数代替除数进行除算的... 论补数除法(上)江璧卿(编者按:本文是作者提交福建省97年度珠算教育研讨会上讨论的论文,内容主要是关于开发补数除法的构想。内文较长,现分三次连载,以飨读者。)一、什么是补数除法补数除法是以除数的补数代替除数进行除算的方法。此法在古代没有统一的名称,最... 展开更多
关键词 补数 除法 现实意义 算法并行 算法解 乘积加 隔位 计算教程 发展过程 乘变数
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Parseval Frame Wavelet Multipliers in L^2(R^d) 被引量:3
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作者 Zhongyan LI Xianliang SHI 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2012年第6期949-960,共12页
Let A be a d x d real expansive matrix. An A-dilation Parseval frame wavelet is a function φ E n2 (Rd), such that the set {|det A|n/2φ(Ant -l) :n ∈ Z, l∈ Zd} forms a Parseval frame for L2 (Rd). A measurab... Let A be a d x d real expansive matrix. An A-dilation Parseval frame wavelet is a function φ E n2 (Rd), such that the set {|det A|n/2φ(Ant -l) :n ∈ Z, l∈ Zd} forms a Parseval frame for L2 (Rd). A measurable function f is called an A-dilation Parseval frame wavelet multiplier if the inverse Fourier transform of fφ is an A-dilation Parseval frame wavelet whenever φ is an A-dilation Parseval frame wavelet, where φ denotes the Fourier transform of φ. In this paper, the authors completely characterize all A-dilation Parseval frame wavelet multipliers for any integral expansive matrix A with | det(A)|= 2. As an application, the path-connectivity of the set of all A-dilation Parseval frame wavelets with a frame MRA in L2(Rd) is discussed. 展开更多
关键词 Parseval frame wavelet Wavelet multiplier Frame multiresolutionanalysis
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Invariant Subspaces of Sobolev Disk Algebra
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作者 刘义强 王宗尧 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2006年第2期233-238,共6页
In this paper, we study the invariant subspaces of the operator Mz on the Sobolev disk algebra R(D) and characterize the invariant subspace with finite codimension.
关键词 Invaxiant subspace Sobolev disk algebra multiplication operator.
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L_p-L_q DECAY ESTIMATES FOR HYPERBOLIC EQUATIONS WITH OSCILLATIONS IN COEFFICIENTS
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作者 M.REISSIG K.YAGDJIAN 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2000年第2期153-164,共12页
This work is concerned with the proof of Lp-Lq decay estimates for solutions of the Cauchy problem for utt-λ2(t)b2(t) △ u =0. The coefficient consists of an increasing smooth function λ and an oscillating smoot... This work is concerned with the proof of Lp-Lq decay estimates for solutions of the Cauchy problem for utt-λ2(t)b2(t) △ u =0. The coefficient consists of an increasing smooth function λ and an oscillating smooth and bounded function b which are uniformly separated from zero. The authors’ main interest is devoted to the critical case where one has an interesting interplay between the growing and the oscillating part. 展开更多
关键词 L_p-L_q decay estimates Wave equation Fourier multipliers
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Study on Adjoint-Based Optimization Method For Multi-Stage Turbomachinery 被引量:6
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作者 Weiwei Li Yong Tian +3 位作者 Weilin Yi Lucheng Ji Weiwei Shao Yunhan Xiao 《Journal of Thermal Science》 SCIE EI CAS CSCD 2011年第5期398-405,共8页
Adjoint-based optimization method is a hotspot in turbomachinery.First,this paper presents principles of adjoint method from Lagrange multiplier viewpoint.Second,combining a continuous route with thin layer RANS equat... Adjoint-based optimization method is a hotspot in turbomachinery.First,this paper presents principles of adjoint method from Lagrange multiplier viewpoint.Second,combining a continuous route with thin layer RANS equations,we formulate adjoint equations and anti-physical boundary conditions.Due to the multi-stage environment in turbomachinery,an adjoint interrow mixing method is introduced.Numerical techniques of solving flow equations and adjoint equations are almost the same,and once they are converged respectively,the gradients of an objective function to design variables can be calculated using complex method efficiently.Third,integrating a shape perturbation parameterization and a simple steepest descent method,a frame of adjoint-based aerodynamic shape optimization for multi-stage turbomachinery is constructed.At last,an inverse design of an annular cascade is employed to validate the above approach,and adjoint field of an Aachen 1.5 stage turbine demonstrates the conservation and areflexia of the adjoint interrow mixing method.Then a direct redesign of a 1+1 counter-rotating turbine aiming to increase efficiency and apply constraints to mass flow rate and pressure ratio is taken. 展开更多
关键词 adjoint method aerodynamic shape optimization multi-stage turbomachinery N-S equations
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Properties and Iterative Methods for the Lasso and Its Variants 被引量:6
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作者 Hong-Kun XU 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2014年第3期501-518,共18页
The lasso of Tibshirani (1996) is a least-squares problem regularized by the l1 norm. Due to the sparseness promoting property of the l1 norm, the lasso has been received much attention in recent years. In this pape... The lasso of Tibshirani (1996) is a least-squares problem regularized by the l1 norm. Due to the sparseness promoting property of the l1 norm, the lasso has been received much attention in recent years. In this paper some basic properties of the lasso and two variants of it are exploited. Moreover, the proximal method and its variants such as the relaxed proximal algorithm and a dual method for solving the lasso by iterative algorithms are presented. 展开更多
关键词 Lasso Elastic net Smooth-lasso l1 regulaxization SPARSITY Proximalmethod Dual method Projection THRESHOLDING
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Shrinkage estimation analysis of correlated binary data with a diverging number of parameters 被引量:2
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作者 XU PeiRong FU WenJiang ZHU LiXing 《Science China Mathematics》 SCIE 2013年第2期359-377,共19页
For analyzing correlated binary data with high-dimensional covariates,we,in this paper,propose a two-stage shrinkage approach.First,we construct a weighted least-squares(WLS) type function using a special weighting sc... For analyzing correlated binary data with high-dimensional covariates,we,in this paper,propose a two-stage shrinkage approach.First,we construct a weighted least-squares(WLS) type function using a special weighting scheme on the non-conservative vector field of the generalized estimating equations(GEE) model.Second,we define a penalized WLS in the spirit of the adaptive LASSO for simultaneous variable selection and parameter estimation.The proposed procedure enjoys the oracle properties in high-dimensional framework where the number of parameters grows to infinity with the number of clusters.Moreover,we prove the consistency of the sandwich formula of the covariance matrix even when the working correlation matrix is misspecified.For the selection of tuning parameter,we develop a consistent penalized quadratic form(PQF) function criterion.The performance of the proposed method is assessed through a comparison with the existing methods and through an application to a crossover trial in a pain relief study. 展开更多
关键词 correlated binary data variable selection diverging number of parameters adaptive LASSO GEE oracle properties sandwich covariance formula penalized quadratic form function
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S^1×S^1-INDEX THEORY ON PRODUCT SPACE
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作者 ZHONGCHENGKUI ZHAOPEIHAO SHIKE 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 1999年第3期363-368,共6页
A new index is constructed by use of the canonical representation of S1 × S1 group over a product space. This index satisfies the general properties of the usual index but does not satifsy the dimension property.... A new index is constructed by use of the canonical representation of S1 × S1 group over a product space. This index satisfies the general properties of the usual index but does not satifsy the dimension property. As an application, two abstract critical point theorems are given. 展开更多
关键词 INDEX Equivariant mapping Critical point Critical value
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