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Study on Characteristics of 3-D Translating-Pulsating Source Green Function of Deep-Water Havelock Form and Its Fast Integration Method 被引量:19
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作者 许勇 董文才 《China Ocean Engineering》 SCIE EI 2011年第3期365-380,共16页
The singularities, oscillatory performances and the contributing factors to the 3-'D translating-pulsating source Green function of deep-water Havelock form which consists of a local disturbance part and a far-field ... The singularities, oscillatory performances and the contributing factors to the 3-'D translating-pulsating source Green function of deep-water Havelock form which consists of a local disturbance part and a far-field wave-like part, are analyzed systematically. Relative numerical integral methods about the two parts are presented in this paper. An improved method based on LOBATTO rule is used to eliminate singularities caused respectively by infinite discontinuity and jump discontinuous node from the local disturbance part function, which makes the improvement of calculation efficiency and accuracy possible. And variable substitution is applied to remove the singularity existing at the end of the integral interval of the far-field wave-like part function. Two auxiliary techniques such as valid interval calculation and local refinement of integral steps technique in narrow zones near false singularities are applied so as to avoid unnecessary integration of invalid interval and improve integral accordance. Numerical test results have proved the efficiency and accuracy in these integral methods that thus can be applied to calculate hydrodynamic performance of floating structures moving in waves. 展开更多
关键词 translating-pulsating source Green's function singularity highly oscillatory function integration method
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A Cauchy integral formula for(p,q)-monogenic functions withα-weight
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作者 GAO Long DU Xiao-jing +1 位作者 LIU Yue XIE Yong-hong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第3期545-553,共9页
Firstly,some properties for(p,q)-monogenic functions withα-weight in Clifford analysis are given.Then,the Cauchy-Pompeiu formula is proved.Finally,the Cauchy integral formula and the Cauchy integral theorem for(p,q)-... Firstly,some properties for(p,q)-monogenic functions withα-weight in Clifford analysis are given.Then,the Cauchy-Pompeiu formula is proved.Finally,the Cauchy integral formula and the Cauchy integral theorem for(p,q)-monogenic functions withα-weight are given. 展开更多
关键词 (p q)-monogenic functions with-weight Cauchy-Pompeiu formula Cauchy integral formula Cauchy integral theorem
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On the global L^(1)-boundedness of Fourier integral operators with rough amplitude and phase functions
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作者 Joachim Sindayigaya WU Xiao-mei HUANG Qiang 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第4期604-613,共10页
Let T_(ϕ,a)be a Fourier integral operator with amplitude a and phase functions ϕ.In this paper,we study the boundedness of Fourier integral operator of rough amplitude a∈L^(∞)S_(ρ)^(m)and rough phase functionsϕ∈L^... Let T_(ϕ,a)be a Fourier integral operator with amplitude a and phase functions ϕ.In this paper,we study the boundedness of Fourier integral operator of rough amplitude a∈L^(∞)S_(ρ)^(m)and rough phase functionsϕ∈L^(m)ϕ^(2)with some measure condition.We prove the global L^(1)boundedness for T_(ϕ,a),when 1/<ρ≤1 and m<ρ-n+1/2.Our theorem improves some known results. 展开更多
关键词 Fourier integral operators L1-Boundedness rough amplitude rough phase functions
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Wave propagation of a functionally graded plate via integral variables with a hyperbolic arcsine function
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作者 Mokhtar Ellali Mokhtar Bouazza Ashraf M.Zenkour 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第3期547-561,共15页
Several studies on functionally graded materials(FGMs)have been done by researchers,but few studies have dealt with the impact of the modification of the properties of materials with regard to the functional propagati... Several studies on functionally graded materials(FGMs)have been done by researchers,but few studies have dealt with the impact of the modification of the properties of materials with regard to the functional propagation of the waves in plates.This work aims to explore the effects of changing compositional characteristics and the volume fraction of the constituent of plate materials regarding the wave propagation response of thick plates of FGM.This model is based on a higher-order theory and a new displacement field with four unknowns that introduce indeterminate integral variables with a hyperbolic arcsine function.The FGM plate is assumed to consist of a mixture of metal and ceramic,and its properties change depending on the power functions of the thickness of the plate,such as linear,quadratic,cubic,and inverse quadratic.By utilizing Hamilton’s principle,general formulae of the wave propagation were obtained to establish wave modes and phase velocity curves of the wave propagation in a functionally graded plate,including the effects of changing compositional characteristics of materials. 展开更多
关键词 FGM plate effects of material properties wave propagation indeterminate integral variables inverse sinus hyperbolic function
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Highly Accurate Golden Section Search Algorithms and Fictitious Time Integration Method for Solving Nonlinear Eigenvalue Problems
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作者 Chein-Shan Liu Jian-Hung Shen +1 位作者 Chung-Lun Kuo Yung-Wei Chen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期1317-1335,共19页
This study sets up two new merit functions,which are minimized for the detection of real eigenvalue and complex eigenvalue to address nonlinear eigenvalue problems.For each eigen-parameter the vector variable is solve... This study sets up two new merit functions,which are minimized for the detection of real eigenvalue and complex eigenvalue to address nonlinear eigenvalue problems.For each eigen-parameter the vector variable is solved from a nonhomogeneous linear system obtained by reducing the number of eigen-equation one less,where one of the nonzero components of the eigenvector is normalized to the unit and moves the column containing that component to the right-hand side as a nonzero input vector.1D and 2D golden section search algorithms are employed to minimize the merit functions to locate real and complex eigenvalues.Simultaneously,the real and complex eigenvectors can be computed very accurately.A simpler approach to the nonlinear eigenvalue problems is proposed,which implements a normalization condition for the uniqueness of the eigenvector into the eigenequation directly.The real eigenvalues can be computed by the fictitious time integration method(FTIM),which saves computational costs compared to the one-dimensional golden section search algorithm(1D GSSA).The simpler method is also combined with the Newton iterationmethod,which is convergent very fast.All the proposed methods are easily programmed to compute the eigenvalue and eigenvector with high accuracy and efficiency. 展开更多
关键词 Nonlinear eigenvalue problem quadratic eigenvalue problem two new merit functions golden section search algorithm fictitious time integration method
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Feynman Path Integral Using Operator Integration in Banach Space
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作者 Reza R. Ahangar Erbil Cetin Serife Muge Ege 《Journal of Applied Mathematics and Physics》 2024年第2期432-444,共13页
Feynman-Path Integral in Banach Space: In 1940, R.P. Feynman attempted to find a mathematical representation to express quantum dynamics of the general form for a double-slit experiment. His intuition on several slits... Feynman-Path Integral in Banach Space: In 1940, R.P. Feynman attempted to find a mathematical representation to express quantum dynamics of the general form for a double-slit experiment. His intuition on several slits with several walls in terms of Lagrangian instead of Hamiltonian resulted in a magnificent work. It was known as Feynman Path Integrals in quantum physics, and a large part of the scientific community still considers them a heuristic tool that lacks a sound mathematical definition. This paper aims to refute this prejudice, by providing an extensive and self-contained description of the mathematical theory of Feynman Path Integration, from the earlier attempts to the latest developments, as well as its applications to quantum mechanics. About a hundred years after the beginning of modern physics, it was realized that light could in fact show behavioral characteristics of both waves and particles. In 1927, Davisson and Germer demonstrated that electrons show the same dual behavior, which was later extended to atoms and molecules. We shall follow the method of integration with some modifications to construct a generalized Lebesgue-Bochner-Stieltjes (LBS) integral of the form , where u is a bilinear operator acting in the product of Banach spaces, f is a Bochner summable function, and μ is a vector-valued measure. We will demonstrate that the Feynman Path Integral is consistent and can be justified mathematically with LBS integration approach. 展开更多
关键词 Feynman Path integral Lebesgue-Bochner-Stieltjes integral Operator integral Particle-Wave function Operator integration Position and Momentum Operators
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THE INTEGRATION OF ALGEBROIDAL FUNCTIONS
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作者 孙道椿 霍颖莹 +1 位作者 孔荫莹 柴富杰 《Acta Mathematica Scientia》 SCIE CSCD 2017年第6期1861-1869,共9页
In this paper, we introduce the integration of algebroidal functions on Riemann surfaces for the first time. Some properties of integration are obtained. By giving the defi- nition of residues and integral function el... In this paper, we introduce the integration of algebroidal functions on Riemann surfaces for the first time. Some properties of integration are obtained. By giving the defi- nition of residues and integral function element, we obtain the condition that the integral is independent of path. At last, we prove that the integral of an irreducible algebroidal function is also an irreducible algebroidal function if all the residues at critical points are zeros. 展开更多
关键词 algebroidal function integrAL integral function element direct continuation
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Multisensory mechanisms of gait and balance in Parkinson’s disease:an integrative review
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作者 Stiven Roytman Rebecca Paalanen +4 位作者 Giulia Carli Uros Marusic Prabesh Kanel Teus van Laar Nico I.Bohnen 《Neural Regeneration Research》 SCIE CAS 2025年第1期82-92,共11页
Understanding the neural underpinning of human gait and balance is one of the most pertinent challenges for 21st-century translational neuroscience due to the profound impact that falls and mobility disturbances have ... Understanding the neural underpinning of human gait and balance is one of the most pertinent challenges for 21st-century translational neuroscience due to the profound impact that falls and mobility disturbances have on our aging population.Posture and gait control does not happen automatically,as previously believed,but rather requires continuous involvement of central nervous mechanisms.To effectively exert control over the body,the brain must integrate multiple streams of sensory information,including visual,vestibular,and somatosensory signals.The mechanisms which underpin the integration of these multisensory signals are the principal topic of the present work.Existing multisensory integration theories focus on how failure of cognitive processes thought to be involved in multisensory integration leads to falls in older adults.Insufficient emphasis,however,has been placed on specific contributions of individual sensory modalities to multisensory integration processes and cross-modal interactions that occur between the sensory modalities in relation to gait and balance.In the present work,we review the contributions of somatosensory,visual,and vestibular modalities,along with their multisensory intersections to gait and balance in older adults and patients with Parkinson’s disease.We also review evidence of vestibular contributions to multisensory temporal binding windows,previously shown to be highly pertinent to fall risk in older adults.Lastly,we relate multisensory vestibular mechanisms to potential neural substrates,both at the level of neurobiology(concerning positron emission tomography imaging)and at the level of electrophysiology(concerning electroencephalography).We hope that this integrative review,drawing influence across multiple subdisciplines of neuroscience,paves the way for novel research directions and therapeutic neuromodulatory approaches,to improve the lives of older adults and patients with neurodegenerative diseases. 展开更多
关键词 aging BALANCE encephalography functional magnetic resonance imaging GAIT multisensory integration Parkinson’s disease positron emission tomography SOMATOSENSORY VESTIBULAR visual
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The Numerical Integration of Discrete Functions on a Triangular Element
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作者 陆宏轮 仇文革 关宝树 《Journal of Modern Transportation》 2001年第1期50-42,51-58,共10页
With the application of Hammer integral formulas of a continuous function on a triangular element, the numerical integral formulas of some discrete functions on the element are derived by means of decomposition and re... With the application of Hammer integral formulas of a continuous function on a triangular element, the numerical integral formulas of some discrete functions on the element are derived by means of decomposition and recombination of base functions. Hammer integral formulas are the special examples of those of the paper. 展开更多
关键词 numerical integration discrete functions finite element method base function triangular element
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The Integration of Dual-domain Method for Estimating the Drift Function of Financial Assets
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作者 YE Xu-guo DU Xue-qiao 《Chinese Quarterly Journal of Mathematics》 CSCD 2011年第2期190-195,共6页
Time-domain state-domain methods are common approaches in modern financial analysis.Economic conditions vary time,drift function depends on time and price level for a given state variable.In this paper,to consistently... Time-domain state-domain methods are common approaches in modern financial analysis.Economic conditions vary time,drift function depends on time and price level for a given state variable.In this paper,to consistently estimate the bivariate drift function,our purpose a new dynamic integrated estimator by combing time-and state-domain methods for estimating drift function.And we establish its asymptotic properties and illustrates it outperforms some old ones by simulations. 展开更多
关键词 TIME-DOMAIN state-domain integrated estimator drift function
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AN INTEGRATION METHOD WITH FITTING CUBIC SPLINE FUNCTIONS TO A NUMERICAL MODEL OF 2ND-ORDER SPACE-TIME DIFFERENTIAL REMAINDER——FOR AN IDEAL GLOBAL SIMULATION CASE WITH PRIMITIVE ATMOSPHERIC EQUATIONS
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作者 辜旭赞 张兵 王明欢 《Journal of Tropical Meteorology》 SCIE 2013年第4期388-396,共9页
In this paper,the forecasting equations of a 2nd-order space-time differential remainder are deduced from the Navier-Stokes primitive equations and Eulerian operator by Taylor-series expansion.Here we introduce a cubi... In this paper,the forecasting equations of a 2nd-order space-time differential remainder are deduced from the Navier-Stokes primitive equations and Eulerian operator by Taylor-series expansion.Here we introduce a cubic spline numerical model(Spline Model for short),which is with a quasi-Lagrangian time-split integration scheme of fitting cubic spline/bicubic surface to all physical variable fields in the atmospheric equations on spherical discrete latitude-longitude mesh.A new algorithm of"fitting cubic spline—time step integration—fitting cubic spline—……"is developed to determine their first-and2nd-order derivatives and their upstream points for time discrete integral to the governing equations in Spline Model.And the cubic spline function and its mathematical polarities are also discussed to understand the Spline Model’s mathematical foundation of numerical analysis.It is pointed out that the Spline Model has mathematical laws of"convergence"of the cubic spline functions contracting to the original functions as well as its 1st-order and 2nd-order derivatives.The"optimality"of the 2nd-order derivative of the cubic spline functions is optimal approximation to that of the original functions.In addition,a Hermite bicubic patch is equivalent to operate on a grid for a 2nd-order derivative variable field.Besides,the slopes and curvatures of a central difference are identified respectively,with a smoothing coefficient of 1/3,three-point smoothing of that of a cubic spline.Then the slopes and curvatures of a central difference are calculated from the smoothing coefficient 1/3 and three-point smoothing of that of a cubic spline,respectively.Furthermore,a global simulation case of adiabatic,non-frictional and"incompressible"model atmosphere is shown with the quasi-Lagrangian time integration by using a global Spline Model,whose initial condition comes from the NCEP reanalysis data,along with quasi-uniform latitude-longitude grids and the so-called"shallow atmosphere"Navier-Stokes primitive equations in the spherical coordinates.The Spline Model,which adopted the Navier-Stokes primitive equations and quasi-Lagrangian time-split integration scheme,provides an initial ideal case of global atmospheric circulation.In addition,considering the essentially non-linear atmospheric motions,the Spline Model could judge reasonably well simple points of any smoothed variable field according to its fitting spline curvatures that must conform to its physical interpretation. 展开更多
关键词 NUMERICAL forecast and NUMERICAL SIMULATION 2nd-order SPACE-TIME differential REMAINDER NUMERICAL model cubic spline functions Navier-Stokes PRIMITIVE EQUATIONS quasi-Lagrangian time-split integration scheme global SIMULATION case
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Research and Review on the Development of Mechanical and Electrical Integration of System Function Principle and Related Technologies
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作者 Zhihai Zhou 《International Journal of Technology Management》 2015年第10期137-139,共3页
In this paper, we conduct research on the development of mechanical and electrical integration of system function principle and related technologies. Along with the rapid and continuous development of modem science an... In this paper, we conduct research on the development of mechanical and electrical integration of system function principle and related technologies. Along with the rapid and continuous development of modem science and technology, it ' s for the penetration and cross of different subjects great push, the more important is caused by technological revolution in the field of engineering and mechanical engineering field under the rapid development of computer technology and microelectronic technology and penetration to the mechanical and electrical integration, which is formed by the mechanical industry lead to trigger a particularly large changes in the mechanical industry management system and mode of production, product and technical structure, composition and function, thus result in industrial production from the previous mechanical electrification progressively electromechanical integration which lead the trend of the current technology. 展开更多
关键词 Mechanical and Electrical integration System function Development Principle.
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New Numerical Integration Formulations for Ordinary Differential Equations
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作者 Serdar Beji 《Advances in Pure Mathematics》 2024年第8期650-666,共17页
An entirely new framework is established for developing various single- and multi-step formulations for the numerical integration of ordinary differential equations. Besides polynomials, unconventional base-functions ... An entirely new framework is established for developing various single- and multi-step formulations for the numerical integration of ordinary differential equations. Besides polynomials, unconventional base-functions with trigonometric and exponential terms satisfying different conditions are employed to generate a number of formulations. Performances of the new schemes are tested against well-known numerical integrators for selected test cases with quite satisfactory results. Convergence and stability issues of the new formulations are not addressed as the treatment of these aspects requires a separate work. The general approach introduced herein opens a wide vista for producing virtually unlimited number of formulations. 展开更多
关键词 Single- and Multi-Step Numerical integration Unconventional Base-functions Ordinary Differential Equations
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INTEGRATION OF A ZONAL FUNCTION RELATED TO THE LOCAL HARMONIC ANALYSIS ON SPHERES
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作者 Sun Limin (Hangzhou University,China) 《Analysis in Theory and Applications》 1996年第3期93-97,共5页
In studying Local harmonic analysis on the sphere S',R.S.Strichartz introduced certain zonab functionsid(x,y))which satisfy the equation
关键词 integration OF A ZONAL function RELATED TO THE LOCAL HARMONIC ANALYSIS ON SPHERES
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Some properties of monotone set functions defined by Choquet integral 被引量:4
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作者 欧阳耀 李军 《Journal of Southeast University(English Edition)》 EI CAS 2003年第4期423-426,共4页
In this paper, some properties of the monotone set function defined by theChoquet integral are discussed. It is shown that several important structural characteristics of theoriginal set function, such as weak null-ad... In this paper, some properties of the monotone set function defined by theChoquet integral are discussed. It is shown that several important structural characteristics of theoriginal set function, such as weak null-additivity, strong order continuity, property (s) andpseudomelric generating property, etc., are preserved by the new set function. It is also shown thatC-integrability assumption is inevitable for the preservations of strong order continuous andpseudometric generating property. 展开更多
关键词 non-additive measure monotone set function choquet integral
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THE BASIC THEORY OF SOLUTIONS OF FUNCTIONAL DIFFERENTIAL EQUATIONS WITH BOUNDED DELAY IN THE SPACE OF INTEGRABLE FUNCTIONS
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作者 刘永清 李远清 《华南理工大学学报(自然科学版)》 EI CAS CSCD 北大核心 1997年第7期67-73,共7页
在可积函数空间中讨论有界滞量泛函微分方程,建立其解的基本理论,包括解的存在性,唯一性及延展性。
关键词 有界滞量的泛函微分方程 存在性 唯一性 延展性 可积函数空间
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Irritable bowel syndrome and functional constipation management with integrative medicine: A systematic review 被引量:17
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作者 Liang Dai Linda LD Zhong Guang Ji 《World Journal of Clinical Cases》 SCIE 2019年第21期3486-3504,共19页
BACKGROUND Irritable bowel syndrome(IBS)and functional constipation(FC)are two commonly encountered functional gastrointestinal disorders in clinical practice and are usually managed with Western medicines in cooperat... BACKGROUND Irritable bowel syndrome(IBS)and functional constipation(FC)are two commonly encountered functional gastrointestinal disorders in clinical practice and are usually managed with Western medicines in cooperation with traditional Chinese medicine(TCM)interventions.Although clinical practice guidelines(CPGs)have been developed to assist clinicians with their decisions,there are still gaps in management with regard to integrative medicine(IM)recommendations.AIM To comprehensively review the currently available CPGs and to provide a reference for addressing the gaps in IBS and FC management.METHODS We searched mainstream English and Chinese databases and collected data from January 1990 to January 2019.The search was additionally enriched by manual searches and the use of publicly available resources.Based on the development method,the guidelines were classified into evidence-based(EB)guidelines,consensus-based(CB)guidelines,and consensus-based guidelines with no comprehensive consideration of the EB(CB-EB)guidelines.With regard to the recommendations,the strength of the interventions was uniformly converted to a 4-point grading scale.RESULTS Thirty CPGs met the inclusion criteria and were captured as data extraction sources.Most Western medicine(WM)CPGs were developed as EB guidelines.All TCM CPGs and most IM CPGs were identified as CB guidelines.Only the 2011 IBS and IM CPG was a CB-EB set of guidelines.Antispasmodics and peppermint oil for pain,loperamide for diarrhea,and linaclotide for constipation polyethylene glycol and lactulose as osmotic laxatives,bisacodyl and sodium picosulfate as stimulant laxatives,lubiprostone and linaclotide as prosecretory agents,and prucalopride were strongly recommended or recommended in FC.TCM interventions were suggested based on pattern differentiation,while the recommendation level was considered to be weak or insufficient.CONCLUSION WM CPGs generally provide a comprehensive management algorithm,although there are still some gaps that could be addressed with TCM.Specific high-quality trials are needed to enrich the evidence. 展开更多
关键词 IRRITABLE BOWEL disease functional CONSTIPATION Clinical practice GUIDELINE integrATIVE MEDICINE Systematic review
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Commutators of Multilinear Singular Integrals with Lipschitz Functions 被引量:9
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作者 WANG WEI XU JING-SHI 《Communications in Mathematical Research》 CSCD 2009年第4期318-328,共11页
The boundedness of commutators of multilinear singular integrals with Lipschitz functions in product Lebesgue spaces is obtained.
关键词 multilinear singular integral Lipschitz function COMMUTATOR maximalfunction
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THE HADAMARD INEQUALITY FOR CONVEX FUNCTION VIA FRACTIONAL INTEGRALS 被引量:4
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作者 M.E.ZDEMR S.S.DRAGOMIR C.YILDIZ 《Acta Mathematica Scientia》 SCIE CSCD 2013年第5期1293-1299,共7页
In this paper, we establish several inequalities for some differantiable mappings that are connected with the Riemann-Liouville fractional integrals. The analysis used in the proofs is fairly elementary.
关键词 Hadamard's inequality convex functions power-mean inequality Riemann-Liouville fractional integration
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Commutators of Weighted Lipschitz Functions and Multilinear Singular Integrals with Non-Smooth Kernels 被引量:3
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作者 LIAN Jia-li MA Bo-lin WU Huo-xiong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2011年第3期353-367,共15页
This paper is devoted to studying the commutators of the multilinear singular integral operators with the non-smooth kernels and the weighted Lipschitz functions. Some mapping properties for two types of commutators o... This paper is devoted to studying the commutators of the multilinear singular integral operators with the non-smooth kernels and the weighted Lipschitz functions. Some mapping properties for two types of commutators on the weighted Lebesgue spaces, which extend and generalize some previous results, are obtained. 展开更多
关键词 COMMUTATOR multilinear singular integral non-smooth kernel weighted Lipschitz function weights.
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