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A study on equivalence of nonlinear energy dissipation between first-order computational homogenization(FOCH)and re duce d-order homogenization(ROH)methods 被引量:2
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作者 Jiajia Yue Zifeng Yuan 《Theoretical & Applied Mechanics Letters》 CSCD 2021年第1期14-19,共6页
Nowadays,studies on the mechanism of macro-scopic nonlinear behavior of materials by accumulation of micro-scopic degradation are attracting more attention from researchers.Among numerous approaches,multiscale methods... Nowadays,studies on the mechanism of macro-scopic nonlinear behavior of materials by accumulation of micro-scopic degradation are attracting more attention from researchers.Among numerous approaches,multiscale methods have been proved as powerful and practical approaches in predicting macro-scopic material status by averaging and homogenizing physical information from associated micro-scopic mate-rial behavior.Usually in mechanical problem,the stress,consistent material modulus,and possible mate-rial state variables are quantities in interest through the upscaling process.However,the energy-related quantities are not studied much.Some initiative work has been done in the early year including but not limited to the Hill-Mandel condition in multiscale framework,which gives that the macro-scopic elastic strain energy density can be computed by volumetric averaging of that in the micro-scale.However,in the nonlinear analysis,the energy dissipation is an important quantity to measure the degradation status.In this manuscript,two typical multiscale methods,the first-order computational homogenization(FOCH)and reduced-order homogenization(ROH),are adopted to numerically analyze a fiber-reinforced compos-ite material with capability in material nonlinearity.With numerical experiments,it can be shown that energy dissipation is the same for both approaches. 展开更多
关键词 Multiscale first-order computational homogenization (FOCH) Reduced-order homogenization(ROH) Energy dissipation Computational certification
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V-BILIPSCHITZ DETERMINACY OF WEIGHTED HOMOGENEOUS ANALYTIC FUNCTION-GERMS ON WEIGHTED HOMOGENEOUS REAL ANALYTIC VARIETIES 被引量:1
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作者 刘恒兴 张敦穆 《Acta Mathematica Scientia》 SCIE CSCD 2010年第4期1249-1256,共8页
In this article, we provide estimates for the degree of V bilipschitz determinacy of weighted homogeneous function germs defined on weighted homogeneous analytic variety V satisfying a convenient Lojasiewicz condition... In this article, we provide estimates for the degree of V bilipschitz determinacy of weighted homogeneous function germs defined on weighted homogeneous analytic variety V satisfying a convenient Lojasiewicz condition.The result gives an explicit order such that the geometrical structure of a weighted homogeneous polynomial function germs is preserved after higher order perturbations. 展开更多
关键词 V bilipschitz determinacy weighted homogeneous polynomial function germs controlled vector field weighted homogeneous control functions
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THE ANALYTICAL PROPERTIES FOR HOMOGENEOUS RANDOM TRANSITION FUNCTIONS 被引量:1
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作者 胡迪鹤 邱育峰 《Acta Mathematica Scientia》 SCIE CSCD 2007年第1期180-192,共13页
The concepts of Markov process in random environment and homogeneous random transition functions are introduced. The necessary and sufficient conditions for homogeneous random transition function are given. The main r... The concepts of Markov process in random environment and homogeneous random transition functions are introduced. The necessary and sufficient conditions for homogeneous random transition function are given. The main results in this article are the analytical properties, such as continuity, differentiability, random Kolmogorov backward equation and random Kolmogorov forward equation of homogeneous random transition functions. 展开更多
关键词 Markov process in random environment random transition function homogeneous random transition function random Kohnogorov backward equation random Kohnogorov forward equation
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A MAXIMAL FUNCTION CHARACTERIZATION 0F HARDY SPACES ON SPACES OF HOMOGENEOUS TYPE 被引量:6
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作者 Li Wenming Zhongshan University, China 《Analysis in Theory and Applications》 1998年第2期12-27,共16页
A new maximal function is introduced in the dual spaces of test function spaces on spaces of homogeneous type. Using this maximal function, we get new characterization of atomic H^p spaces.
关键词 A MAXIMAL function CHARACTERIZATION 0F HARDY SPACES ON SPACES OF homogeneous TYPE APPI 尸气
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ESTIMATES OF ALL TERMS OF HOMOGENEOUS POLYNOMIAL EXPANSIONS FOR THE SUBCLASSES OF G-PARAMETRIC STARLIKE MAPPINGS OF COMPLEX ORDER IN SEVERAL COMPLEX VARIABLES
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作者 Liangpeng XIONG Qingchao WANG Xiaoying SIMA 《Acta Mathematica Scientia》 2025年第4期1555-1566,共12页
In this paper,the class of starlike functions of complex order γ(γ∈ℂ−{0})is extended from the case on unit disk U=(z∈C:|z|<1)to the case on the unit ball B in a complex Banach space or the unit polydisk U^(n) i... In this paper,the class of starlike functions of complex order γ(γ∈ℂ−{0})is extended from the case on unit disk U=(z∈C:|z|<1)to the case on the unit ball B in a complex Banach space or the unit polydisk U^(n) in C^(n).Let g be a convex function in U. We mainly establish the sharp bounds of all terms of homogeneous polynomial expansions for a subclass of g-parametric starlike mappings of complex order γ on B (resp.U^(n))when the mappings f are k-fold symmetric, k ∈ N. Our results partly solve the Bieberbach conjecture in several complex variables and generalize some prior works. 展开更多
关键词 class starlike functions complex order g parametric starlike mappings unit polydisk bieberbach co convex function homogeneous polynomial expansions banach space
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GENERALIZED HOMOGENEOUS FUNCTIONS AND THE TWO-BODY PROBLEM
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作者 C.Biasi S.M.S.Godoy 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2005年第2期171-178,共8页
A generalization of the homogeneous function concept is studied.An application is done with a solution of the two-body problem.
关键词 homogeneous function generalized homogeneous function Kepler's second law two-body problem
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A closure model on velocity structure functions in homogeneous isotropic turbulence
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作者 Le FANG Feng GAO 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2017年第11期1627-1634,共8页
Closure models started from Chou's work have been developed for more than 70 years, aiming at providing analytical tools to describe turbulent flows in the spectral space. In this study, a preliminary attempt is pres... Closure models started from Chou's work have been developed for more than 70 years, aiming at providing analytical tools to describe turbulent flows in the spectral space. In this study, a preliminary attempt is presented to introduce a closure model in the physical space, using the velocity structure functions as key parameters. The present closure model appears to qualitatively reproduce the asymptotic scaling behav- iors at small and large scales, despite some inappropriate behaviors such as oscillations. Therefore, further improvements of the present model are expected to provide appropriate descriptions of turbulent flows in the physical space. 展开更多
关键词 homogeneous isotropic turbulence closure model structure function
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COMMUTATORS OF BMO FUNCTIONS AND SINGULAR INTEGRAL OPERATORS WITH NON-SMOOTH KERNELS ON SPACES OF HOMOGENEOUS TYPE OF FINITE MEASURE
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作者 Donggao Deng Yanbo Xu Lixin Yan 《Analysis in Theory and Applications》 2006年第1期41-55,共15页
Let X be a space of homogeneous type with finite measure. Let T be a singular integral operator which is bounded on L^p (X), 1 〈 p 〈 ∞. We give a sufficient condition on the kernel k(x,y) of Tso thatwhen a func... Let X be a space of homogeneous type with finite measure. Let T be a singular integral operator which is bounded on L^p (X), 1 〈 p 〈 ∞. We give a sufficient condition on the kernel k(x,y) of Tso thatwhen a function b ∈ BMO (X),the commutator [b,T] (f)=T (b f)- bT (f) is bounded on spaces L^p for all p, 1 〈 p 〈 ∞. 展开更多
关键词 COMMUTATOR homogeneous space BMO function singular integral operator
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The Zeros of a Certain Homogeneous Difference Polynomials of Meromorphic Functions
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作者 Qian Lu Qilong Liao 《Advances in Pure Mathematics》 2013年第1期99-104,共6页
Let f(z) be a function transcendental and meromorphic in the plane of growth order less than 1. This paper focuses on discuss and estimate the number of the zeros of a certain homogeneous difference polynomials of deg... Let f(z) be a function transcendental and meromorphic in the plane of growth order less than 1. This paper focuses on discuss and estimate the number of the zeros of a certain homogeneous difference polynomials of degree k in f(z), and obtains that this certain homogeneous difference polynomials has infinitely many zeros. 展开更多
关键词 MEROMORPHIC functions ZEROS homogeneous DIFFERENCE POLYNOMIALS
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Fast First-Order Methods for Minimizing Convex Composite Functions
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作者 Qipeng Li Hongwei Liu Zexian Liu 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2019年第6期46-52,共7页
Two new versions of accelerated first-order methods for minimizing convex composite functions are proposed. In this paper, we first present an accelerated first-order method which chooses the step size 1/ Lk to be 1/ ... Two new versions of accelerated first-order methods for minimizing convex composite functions are proposed. In this paper, we first present an accelerated first-order method which chooses the step size 1/ Lk to be 1/ L0 at the beginning of each iteration and preserves the computational simplicity of the fast iterative shrinkage-thresholding algorithm. The first proposed algorithm is a non-monotone algorithm. To avoid this behavior, we present another accelerated monotone first-order method. The proposed two accelerated first-order methods are proved to have a better convergence rate for minimizing convex composite functions. Numerical results demonstrate the efficiency of the proposed two accelerated first-order methods. 展开更多
关键词 first-order method iterative shrinkage-thresholding algorithm convex programming adaptive restart composite functions.
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A Proof for the Nonexistence of Some Homogeneous Bent Functions
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作者 MENG Qing-shu ZHANG Huan-guo +1 位作者 QIN Zhong-ping WANG Zhang-yi 《Wuhan University Journal of Natural Sciences》 CAS 2005年第3期504-506,共3页
By the relationship between the first linear spectra of a function at partialpoints and the Hamming weights of the sub-functions,and by the Hamming weight of homogenousBoolean function,it is proved that there exist no... By the relationship between the first linear spectra of a function at partialpoints and the Hamming weights of the sub-functions,and by the Hamming weight of homogenousBoolean function,it is proved that there exist no homogeneous bent functions ofdegree in in n=2mvariables for m>3. 展开更多
关键词 homogeneous bent functions Walsh transformation Hamming weight
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A Direct Calculation of First-Order Wave Function of Helium
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作者 Boniface Otieno Ndinya Joseph Akeyo Omolo 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第10期647-650,共4页
We develop a simple analytic calculation for the first order wave function of helium in a model in which nuclear charge screening is caused by repulsive coulomb interaction. The perturbation term, first-order correlat... We develop a simple analytic calculation for the first order wave function of helium in a model in which nuclear charge screening is caused by repulsive coulomb interaction. The perturbation term, first-order correlation energy, and first-order wave function are divided into two components, one component associated with the repulsive coulomb interaction and the other proportional to magnetic shielding. The resulting first-order wave functions are applied to calculate second-order energies within the model. We find that the second-order energies are independent of the nuclear charge screening constant in the unperturbed Hamiltonian with a central coulomb potential. 展开更多
关键词 nuclear charge screening first-order wave function and second-order energy
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Existence and Uniqueness of Positive Periodic Solutions for First-order Functional Differential Equations
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作者 HAN Qian-qian ZHAI Cheng-bo 《Chinese Quarterly Journal of Mathematics》 CSCD 2013年第3期454-461,共8页
In this paper, we prove the existence and uniqueness of positive periodic solutions for first-order functional differential equation y'(t) = α(t)y(t) + f(t, y(t -τ-(t))) + g(t)by using two fixed poi... In this paper, we prove the existence and uniqueness of positive periodic solutions for first-order functional differential equation y'(t) = α(t)y(t) + f(t, y(t -τ-(t))) + g(t)by using two fixed point theorems of general α-concave operators and homogeneous operators in ordered Banach spaces. 展开更多
关键词 functional differential equation existence and uniqueness positive periodics olution~ general s-concave operator homogeneous operator
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A radiomics approach for predicting gait freezing in Parkinson's disease based on resting-state functional magnetic resonance imaging indices:A cross-sectional study
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作者 Miaoran Guo Hu Liu +6 位作者 Long Gao Hongmei Yu Yan Ren Yingmei Li Huaguang Yang Chenghao Cao Guoguang Fan 《Neural Regeneration Research》 2026年第4期1621-1627,共7页
Freezing of gait is a significant and debilitating motor symptom often observed in individuals with Parkinson's disease.Resting-state functional magnetic resonance imaging,along with its multi-level feature indice... Freezing of gait is a significant and debilitating motor symptom often observed in individuals with Parkinson's disease.Resting-state functional magnetic resonance imaging,along with its multi-level feature indices,has provided a fresh perspective and valuable insight into the study of freezing of gait in Parkinson's disease.It has been revealed that Parkinson's disease is accompanied by widespread irregularities in inherent brain network activity.However,the effective integration of the multi-level indices of resting-state functional magnetic resonance imaging into clinical settings for the diagnosis of freezing of gait in Parkinson's disease remains a challenge.Although previous studies have demonstrated that radiomics can extract optimal features as biomarkers to identify or predict diseases,a knowledge gap still exists in the field of freezing of gait in Parkinson's disease.This cross-sectional study aimed to evaluate the ability of radiomics features based on multi-level indices of resting-state functional magnetic resonance imaging,along with clinical features,to distinguish between Parkinson's disease patients with and without freezing of gait.We recruited 28 patients with Parkinson's disease who had freezing of gait(15 men and 13 women,average age 63 years)and 30 patients with Parkinson's disease who had no freezing of gait(16 men and 14 women,average age 64 years).Magnetic resonance imaging scans were obtained using a 3.0T scanner to extract the mean amplitude of low-frequency fluctuations,mean regional homogeneity,and degree centrality.Neurological and clinical characteristics were also evaluated.We used the least absolute shrinkage and selection operator algorithm to extract features and established feedforward neural network models based solely on resting-state functional magnetic resonance imaging indicators.We then performed predictive analysis of three distinct groups based on resting-state functional magnetic resonance imaging indicators indicators combined with clinical features.Subsequently,we conducted 100 additional five-fold cross-validations to determine the most effective model for each classification task and evaluated the performance of the model using the area under the receiver operating characteristic curve.The results showed that when differentiating patients with Parkinson's disease who had freezing of gait from those who did not have freezing of gait,or from healthy controls,the models using only the mean regional homogeneity values achieved the highest area under the receiver operating characteristic curve values of 0.750(with an accuracy of 70.9%)and 0.759(with an accuracy of 65.3%),respectively.When classifying patients with Parkinson's disease who had freezing of gait from those who had no freezing of gait,the model using the mean amplitude of low-frequency fluctuation values combined with two clinical features achieved the highest area under the receiver operating characteristic curve of 0.847(with an accuracy of 74.3%).The most significant features for patients with Parkinson's disease who had freezing of gait were amplitude of low-frequency fluctuation alterations in the left parahippocampal gyrus and two clinical characteristics:Montreal Cognitive Assessment and Hamilton Depression Scale scores.Our findings suggest that radiomics features derived from resting-state functional magnetic resonance imaging indices and clinical information can serve as valuable indices for the identification of freezing of gait in Parkinson's disease. 展开更多
关键词 amplitude of low-frequency fluctuation degree centrality feedforward neural network freezing of gait machine learning parahippocampal gyrus Parkinson's disease receiver operating characteristic regional homogeneity resting-state functional magnetic resonance imaging
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Approximate Quadratic Functional Inequality in β-Homogeneous Normed Spaces
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作者 Zhihua WANG 《Journal of Mathematical Research with Applications》 CSCD 2020年第1期26-32,共7页
Using the direct method,we investigate the generalized Hyers-Ulam stability of the following quadratic functional inequality■inβ-homogeneous complex Banach spaces.
关键词 β-homogeneous space generalized Hyers-Ulam stability quadratic functional inequality
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On Enforcing Dyadic-type Homogeneous Binary Function Product Constraints in MatBase
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作者 Christian Mancas 《Journal of Computer Science Research》 2024年第1期31-42,共12页
Homogeneous binary function products are frequently encountered in the sub-universes modeled by databases,spanning from genealogical trees and sports to education and healthcare,etc.Their properties must be discovered... Homogeneous binary function products are frequently encountered in the sub-universes modeled by databases,spanning from genealogical trees and sports to education and healthcare,etc.Their properties must be discovered and enforced by the software applications managing such data to guarantee plausibility.The(Elementary)Mathematical Data Model provides 17 types of dyadic-based homogeneous binary function product constraint categories.MatBase,an intelligent data and knowledge base management system prototype,allows database designers to simply declare them by only clicking corresponding checkboxes and automatically generates code for enforcing them.This paper describes the algorithms that MatBase uses for enforcing all 17 types of homogeneous binary function product constraint,which may also be employed by developers without access to MatBase. 展开更多
关键词 Database constraints homogeneous binary function products Dyadic relations Modelling as programming The(Elementary)Mathematical Data Model MatBase
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Altered regional homogeneity in post-traumatic stress disorder: a resting-state functional magnetic resonance imaging study 被引量:11
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作者 Yan Yin Changfeng Jin +9 位作者 Lisa T. Eyler Hua Jin Xiaolei Hu Lian Duan Huirong Zheng Bo Feng Xuanyin Huang Baoci Shan Qiyong Gong Lingjiang Li 《Neuroscience Bulletin》 SCIE CAS CSCD 2012年第5期541-549,共9页
Objective Little is known about the brain systems that contribute to vulnerability to post-traumatic stress disorder (PTSD). Comparison of the resting-state patterns of intrinsic functional synchronization, as measu... Objective Little is known about the brain systems that contribute to vulnerability to post-traumatic stress disorder (PTSD). Comparison of the resting-state patterns of intrinsic functional synchronization, as measured by functional magnetic resonance imaging (fMRI), between groups with and without PTSD following a traumatic event can help identify the neural mechanisms of the disorder and targets for intervention. Methods Fifty-four PTSD patients and 72 matched traumatized subjects who experienced the 2008 Sichuan earthquake were imaged with blood oxygen level-dependent (BOLD) fMRI and analyzed using the measure of regional homogeneity (ReHo) during the resting state. Results PTSD patients presented enhanced ReHo in the left inferior parietal lobule and right superior frontal gyrus, and reduced ReHo in the right middle temporal gyrus and lingual gyrus, relative to traumatized individuals without PTSD. Conclusion Our findings showed that abnormal brain activity exists under resting conditions in PTSD patients who had been exposed to a major earthquake. Alterations in the local functional connectivity of cortical regions are likely to contribute to the neural mechanisms underlying PTSD. 展开更多
关键词 functional magnetic resonance imaging post-traumatic stress disorder regional homogeneity RESTING-STATE
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Boundedness of Linear Commutators on Herz-Morrey Spaces on Spaces of Homogeneous Type 被引量:3
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作者 GAO Wen-hua JIANG Yin-sheng GONG Xiao-bing 《Chinese Quarterly Journal of Mathematics》 CSCD 2010年第2期172-181,共10页
Under certain weak local size conditions, the boundedness of linear commutators on Herz-Morrey spaces on spaces of homogeneous type are studied. In addition, the boundedness of Hardy-Littlewood maximum commutators on ... Under certain weak local size conditions, the boundedness of linear commutators on Herz-Morrey spaces on spaces of homogeneous type are studied. In addition, the boundedness of Hardy-Littlewood maximum commutators on Herz-Morrey spaces on spaces of homogeneous type are obtained. 展开更多
关键词 homogeneous spaces Herz spaces COMMUTATORS Hardy-Littlewood maximum function
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EXPERIMENTAL EVALUATION ON MODULUS OF EQUIVALENT HOMOGENEOUS ETTRINGITE 被引量:1
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作者 Minghua Zhang Jiankang Chen Jue Zhu Jiangying Chen 《Acta Mechanica Solida Sinica》 SCIE EI 2009年第4期320-327,共8页
In the present study, the average modulus of delayed ettringite is evaluated by an experimental method combined with theoretical analysis. Firstly, the delayed ettringite crystal is synthesized by chemical reaction of... In the present study, the average modulus of delayed ettringite is evaluated by an experimental method combined with theoretical analysis. Firstly, the delayed ettringite crystal is synthesized by chemical reaction of Aluminum sulfate and calcium hydroxide. Secondly, specimens are obtained by compressing the delayed ettringite crystal under different pre-loads. Thirdly, the variation of the modulus of the specimen with different pre-loads is tested using Instron material test machine and the SHPB technique, respectively. It is found that the experimental data may be suitably fitted by Boltzmann Function. Finally, the porosity of the specimen is detected using the saturation method, and the effect of the porosity on the modulus is analyzed by the Eshelby's equivalent inclusion method and the Mori-Tanaka's scheme. The static and dynamic modulli of the equivalent homogeneous ettringite obtained in present study are approximately 10.64 GPa and 24.61 GPa, respectively. 展开更多
关键词 ETTRINGITE equivalent homogeneous materials Boltzmann function MODULUS
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COMMUTATORS OF GENERALIZED HARDY OPERATORS ON HOMOGENEOUS GROUPS 被引量:1
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作者 默会霞 《Acta Mathematica Scientia》 SCIE CSCD 2010年第3期897-906,共10页
Let G be a homogeneous group. The author considers the boundedness of commutators generated by the generalized Hardy operators and CMO(G) functions on Herz spaces in the setting of homogeneous group. This article ex... Let G be a homogeneous group. The author considers the boundedness of commutators generated by the generalized Hardy operators and CMO(G) functions on Herz spaces in the setting of homogeneous group. This article extends some known results. 展开更多
关键词 homogeneous group CMO(G) function Herz space generalized Hardy operator
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