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A Technique for Estimation of Box Dimension about Fractional Integral
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作者 Ruhua Zhang 《Advances in Pure Mathematics》 2023年第10期714-724,共11页
This paper discusses further the roughness of Riemann-Liouville fractional integral on an arbitrary fractal continuous functions that follows Rfs. [1]. A novel method is used to reach a similar result for an arbitrary... This paper discusses further the roughness of Riemann-Liouville fractional integral on an arbitrary fractal continuous functions that follows Rfs. [1]. A novel method is used to reach a similar result for an arbitrary fractal function , where is the Riemann-Liouville fractional integral. Furthermore, a general resultis arrived at for 1-dimensional fractal functions such as with unbounded variation and(or) infinite lengths, which can infer all previous studies such as [2] [3]. This paper’s estimation reveals that the fractional integral does not increase the fractal dimension of f(x), i.e. fractional integration does not increase at least the fractal roughness. And the result has partly answered the fractal calculus conjecture and completely answered this conjecture for all 1-dimensional fractal function (Xiao has not answered). It is significant with a comparison to the past researches that the box dimension connection between a fractal function and its Riemann-Liouville integral has been carried out only for Weierstrass type and Besicovitch type functions, and at most Hlder continuous. Here the proof technique for Riemann-Liouville fractional integral is possibly of methodology to other fractional integrals. 展开更多
关键词 Upper Box Dimension riemann-liouville fractional integral Fractal Continuous Function Box Dimension
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Some New Delay Integral Inequalities Based on Modified Riemann-Liouville Fractional Derivative and Their Applications
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作者 Zhimin Zhao Run Xu 《Journal of Applied Mathematics and Physics》 2015年第5期465-477,共13页
By using the properties of modified Riemann-Liouville fractional derivative, some new delay integral inequalities have been studied. First, we offered explicit bounds for the unknown functions, then we applied the res... By using the properties of modified Riemann-Liouville fractional derivative, some new delay integral inequalities have been studied. First, we offered explicit bounds for the unknown functions, then we applied the results to the research concerning the boundness, uniqueness and continuous dependence on the initial for solutions to certain fractional differential equations. 展开更多
关键词 MODIFIED riemann-liouville fractional DERIVATIVE integral INEQUALITIES DELAY fractional Differential Equation
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Characterization of image spaces of Riemann-Liouville fractional integral operators on Sobolev spaces W^(m,p)(Ω)
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作者 Lijing Zhao Weihua Deng Jan S.Hesthaven 《Science China Mathematics》 SCIE CSCD 2021年第12期2611-2636,共26页
Fractional operators are widely used in mathematical models describing abnormal and nonlocal phenomena.Although there are extensive numerical methods for solving the corresponding model problems,theoretical analysis s... Fractional operators are widely used in mathematical models describing abnormal and nonlocal phenomena.Although there are extensive numerical methods for solving the corresponding model problems,theoretical analysis such as the regularity result,or the relationship between the left-side and right-side fractional operators is seldom mentioned.Instead of considering the fractional derivative spaces,this paper starts from discussing the image spaces of Riemann-Liouville fractional integrals of L_(p)(Ω) functions,since the fractional derivative operators that are often used are all pseudo-differential.Then the high regularity situation-the image spaces of Riemann-Liouville fractional integral operators on the W^(m,p)(Ω) space is considered.Equivalent characterizations of the defined spaces,as well as those of the intersection of the left-side and right-side spaces are given.The behavior of the functions in the defined spaces at both the nearby boundary point/points and the points in the domain is demonstrated in a clear way.Besides,tempered fractional operators are shown to be reciprocal to the corresponding Riemann-Liouville fractional operators,which is expected to contribute some theoretical support for relevant numerical methods.Last,we also provide some instructions on how to take advantage of the introduced spaces when numerically solving fractional equations. 展开更多
关键词 image space riemann-liouville integral regularity property APPROXIMATION
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THE FRACTIONAL TYPE MARCINKIEWICZ INTEGRALS AND COMMUTATORS ON WEIGHTED HARDY SPACES
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作者 韩妍妍 伍火熊 《Acta Mathematica Scientia》 SCIE CSCD 2023年第5期1981-1996,共16页
This paper is devoted to studying the behaviors of the fractional type Marcinkiewicz integralsμΩ,βand the commutatorsμΩ,βb generated byμΩ,βwith b b∈Lloc(Rn)on weighted Hardy spaces.Under the assumption of th... This paper is devoted to studying the behaviors of the fractional type Marcinkiewicz integralsμΩ,βand the commutatorsμΩ,βb generated byμΩ,βwith b b∈Lloc(Rn)on weighted Hardy spaces.Under the assumption of that the homogeneous kernelΩsatisfies certain regularities,the authors obtain the boundedness ofμΩ,βfrom the weighted Hardy spaces Hωpp(Rn)to the weighted Lebesgue spaces Lωqq(Rn)for n/(n+β)≤<p≤1 with 1/q=1/p-β/n,as well as the same(Hωpp,Lωqq)-boudedness ofμΩ,βb when b belongs to BMOωp,p(Rn),which is a non-trivial subspace of BMO(Rn). 展开更多
关键词 fractional type Marcinkiewicz integrals COMMUTATORS Muckenhoupt weights BMO spaces Hardy spaces
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Chromatin condensation but not DNA integrity of pig sperm is greater in the sperm-rich fraction
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作者 Estel Viñolas-Vergés Jordi Ribas-Maynou +4 位作者 Isabel Barranco Camila Peres Rubio Sergi Bonet Jordi Roca Marc Yeste 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第1期171-181,共11页
Background Protamination and condensation of sperm chromatin as well as DNA integrity play an essential role during fertilization and embryo development.In some mammals,like pigs,ejaculates are emitted in three separa... Background Protamination and condensation of sperm chromatin as well as DNA integrity play an essential role during fertilization and embryo development.In some mammals,like pigs,ejaculates are emitted in three separate fractions:pre-sperm,sperm-rich(SRF)and post sperm-rich(PSRF).These fractions are known to vary in volume,sperm concentration and quality,as well as in the origin and composition of seminal plasma(SP),with differences being also observed within the SRF one.Yet,whether disparities in the DNA integrity and chromatin condensation and pro-tamination of their sperm exist has not been interrogated.Results This study determined chromatin protamination(Chromomycin A3 test,CMA_(3)),condensation(Dibromobi-mane test,DBB),and DNA integrity(Comet assay)in the pig sperm contained in the first 10 m L of the SRF(SRF-P1),the remaining portion of the sperm-rich fraction(SRF-P2),and the post sperm-rich fraction(PSRF).While chromatin protamination was found to be similar between the different ejaculate fractions(P>0.05),chromatin condensation was seen to be greater in SRF-P1 and SRF-P2 than in the PSRF(P=0.018 and P=0.004,respectively).Regarding DNA integrity,no differences between fractions were observed(P>0.05).As the SRF-P1 has the highest sperm concentra-tion and ejaculate fractions are known to differ in antioxidant composition,the oxidative stress index(OSi)in SP,calcu-lated as total oxidant activity divided by total antioxidant capacity,was tested and confirmed to be higher in the SRF-P1 than in SRF-P2 and PSRF(0.42±0.06 vs.0.23±0.09 and 0.08±0.00,respectively;P<0.01);this index,in addition,was observed to be correlated to the sperm concentration of each fraction(Rs=0.973;P<0.001).Conclusion While sperm DNA integrity was not found to differ between ejaculate fractions,SRF-P1 and SRF-P2 were observed to exhibit greater chromatin condensation than the PSRF.This could be related to the OSi of each fraction. 展开更多
关键词 CHROMATIN Condensation DNA integrity Ejaculate fractions PIG Protamination SPERM
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协同拟凸函数的Riemann-Liouville分数阶积分不等式
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作者 郑茜 王淑红 《内蒙古民族大学学报(自然科学版)》 2024年第2期46-53,共8页
基于Riemann-Liouville分数阶积分,对协同拟凸函数的Hermite-Hadamard分数阶积分不等式进行了研究。剖析Riemann-Liouville分数阶积分的运算特点,深入探究SAR?KAYA给出的Riemann-Liouville分数阶积分恒等式。在该Riemann-Liouville分数... 基于Riemann-Liouville分数阶积分,对协同拟凸函数的Hermite-Hadamard分数阶积分不等式进行了研究。剖析Riemann-Liouville分数阶积分的运算特点,深入探究SAR?KAYA给出的Riemann-Liouville分数阶积分恒等式。在该Riemann-Liouville分数阶积分恒等式的基础上,利用二元函数的单调性和协同拟凸性,巧妙应用三角不等式和H?lder不等式等经典不等式,建立了若干个协同拟凸函数的Hermite-Hadamard分数阶积分不等式。 展开更多
关键词 协同拟凸函数 HERMITE-HADAMARD不等式 riemann-liouville分数阶积分
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Time series analysis-based seasonal autoregressive fractionally integrated moving average to estimate hepatitis B and C epidemics in China
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作者 Yong-Bin Wang Si-Yu Qing +3 位作者 Zi-Yue Liang Chang Ma Yi-Chun Bai Chun-Jie Xu 《World Journal of Gastroenterology》 SCIE CAS 2023年第42期5716-5727,共12页
BACKGROUND Hepatitis B(HB)and hepatitis C(HC)place the largest burden in China,and a goal of eliminating them as a major public health threat by 2030 has been set.Making more informed and accurate forecasts of their s... BACKGROUND Hepatitis B(HB)and hepatitis C(HC)place the largest burden in China,and a goal of eliminating them as a major public health threat by 2030 has been set.Making more informed and accurate forecasts of their spread is essential for developing effective strategies,heightening the requirement for early warning to deal with such a major public health threat.AIM To monitor HB and HC epidemics by the design of a paradigmatic seasonal autoregressive fractionally integrated moving average(SARFIMA)for projections into 2030,and to compare the effectiveness with the seasonal autoregressive integrated moving average(SARIMA).METHODS Monthly HB and HC incidence cases in China were obtained from January 2004 to June 2023.Descriptive analysis and the Hodrick-Prescott method were employed to identify trends and seasonality.Two periods(from January 2004 to June 2022 and from January 2004 to December 2015,respectively)were used as the training sets to develop both models,while the remaining periods served as the test sets to evaluate the forecasting accuracy.RESULTS There were incidents of 23400874 HB cases and 3590867 HC cases from January 2004 to June 2023.Overall,HB remained steady[average annual percentage change(AAPC)=0.44,95%confidence interval(95%CI):-0.94-1.84]while HC was increasing(AAPC=8.91,95%CI:6.98-10.88),and both had a peak in March and a trough in February.In the 12-step-ahead HB forecast,the mean absolute deviation(15211.94),root mean square error(18762.94),mean absolute percentage error(0.17),mean error rate(0.15),and root mean square percentage error(0.25)under the best SARFIMA(3,0,0)(0,0.449,2)12 were smaller than those under the best SARIMA(3,0,0)(0,1,2)12(16867.71,20775.12,0.19,0.17,and 0.27,respectively).Similar results were also observed for the 90-step-ahead HB,12-step-ahead HC,and 90-step-ahead HC forecasts.The predicted HB incidents totaled 9865400(95%CI:7508093-12222709)cases and HC totaled 1659485(95%CI:856681-2462290)cases during 2023-2030.CONCLUSION Under current interventions,China faces enormous challenges to eliminate HB and HC epidemics by 2030,and effective strategies must be reinforced.The integration of SARFIMA into public health for the management of HB and HC epidemics can potentially result in more informed and efficient interventions,surpassing the capabilities of SARIMA. 展开更多
关键词 HEPATITIS Seasonal autoregressive fractionally integrated moving average Seasonal autoregressive integrated moving average Prediction EPIDEMIC Time series analysis
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AN INTEGRATION BY PARTS FORMULA FOR STOCHASTIC HEAT EQUATIONS WITH FRACTIONAL NOISE
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作者 尹修伟 《Acta Mathematica Scientia》 SCIE CSCD 2023年第1期349-362,共14页
In this paper,we establish the integration by parts formula for the solution of fractional noise driven stochastic heat equations using the method of coupling.As an application,we also obtain the shift Harnack inequal... In this paper,we establish the integration by parts formula for the solution of fractional noise driven stochastic heat equations using the method of coupling.As an application,we also obtain the shift Harnack inequalities. 展开更多
关键词 integration by parts formula stochastic heat equations fractional Brownian motion shift Harnack inequality coupling by change of measures
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基于Riemann-Liouville分数阶积分Bernstein-Kantorovich算子的逼近性质
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作者 汪洋 程文韬 +1 位作者 刘玉洁 刘磊 《淮北师范大学学报(自然科学版)》 CAS 2024年第1期27-32,共6页
文章构造一种基于Riemann-Liouville分数阶积分的Bernstein-Kantorovich算子。利用一阶、二阶光滑模、Peetre’-K泛函和Lipschitz型极大函数等工具研究该算子的近似性质。然后利用一阶、二阶和四阶中心矩对该算子建立Vorononskaja型渐... 文章构造一种基于Riemann-Liouville分数阶积分的Bernstein-Kantorovich算子。利用一阶、二阶光滑模、Peetre’-K泛函和Lipschitz型极大函数等工具研究该算子的近似性质。然后利用一阶、二阶和四阶中心矩对该算子建立Vorononskaja型渐进公式。该算子的构建使得在曲线曲面造型方面对于给定的函数将会有更小的近似误差。 展开更多
关键词 BERNSTEIN-KANTOROVICH算子 riemann-liouville分数阶积分 Peetre’-K泛函 Vorononskaja定理
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CBMO Estimates for Commutators of Fractional Integral Operators with Variable Kernels 被引量:2
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作者 WANG Li-wei SHU Li-sheng QU Meng 《Chinese Quarterly Journal of Mathematics》 CSCD 2012年第1期68-73,共6页
In this paper,the authors introduce the central bounded oscillation space CBMO q (R n),let [b,T,α ] be the commutator generated by fractional integral operators with variable kernels and CBMO function,we establish th... In this paper,the authors introduce the central bounded oscillation space CBMO q (R n),let [b,T,α ] be the commutator generated by fractional integral operators with variable kernels and CBMO function,we establish the boundedness of [b,T,α ] on homogeneous Morrey-Herz spaces. 展开更多
关键词 CBMO Morrey-Herz space fractional integral COMMUTATOR variable kernel
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Existence of positive solutions for integral boundary value problem of fractional differential equations 被引量:4
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作者 Xiping Liu Guiyun Wu 《上海师范大学学报(自然科学版)》 2014年第5期496-505,共10页
In this paper,we concern ourselves with the existence of positive solutions for a type of integral boundary value problem of fractional differential equations with the fractional order linear derivative operator. By u... In this paper,we concern ourselves with the existence of positive solutions for a type of integral boundary value problem of fractional differential equations with the fractional order linear derivative operator. By using the fixed point theorem in cone,the existence of positive solutions for the boundary value problem is obtained. Some examples are also presented to illustrate the application of our main results. 展开更多
关键词 fractional differential equations riemann-liouville fractional derivative fixed point theorem fractional order linear derivative operator
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Upper Bound Estimation of Fractal Dimensions of Fractional Integral of Continuous Functions 被引量:3
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作者 Yongshun Liang 《Advances in Pure Mathematics》 2015年第1期27-30,共4页
Fractional integral of continuous functions has been discussed in the present paper. If the order of Riemann-Liouville fractional integral is v, fractal dimension of Riemann-Liouville fractional integral of any contin... Fractional integral of continuous functions has been discussed in the present paper. If the order of Riemann-Liouville fractional integral is v, fractal dimension of Riemann-Liouville fractional integral of any continuous functions on a closed interval is no more than 2 - v. 展开更多
关键词 BOX DIMENSION riemann-liouville fractional CALCULUS FRACTAL Function
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FRACTIONAL INTEGRAL AND FRACTAL FUNCTION 被引量:1
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作者 Sun Qingjie(孙青杰) +1 位作者 Su Weiyi(苏维宜) 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2002年第1期70-75,共6页
In this paper, the relationship between Riemann-Liouville fractional integral and the box-counting dimension of graphs of fractal functions is discussed.
关键词 fractional integral factal function box-counting dimension.
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Boundedness of Fractional Integral with Variable Kernel and Their Commutators on Variable Exponent Herz Spaces 被引量:3
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作者 Afif Abdalmonem Omer Abdalrhman Shuangping Tao 《Applied Mathematics》 2016年第10期1165-1182,共19页
In this paper, we study the boundedness of the fractional integral operator and their commutator on Herz spaecs with two variable exponents . By using the properties of the variable exponents Lebesgue spaces, the boun... In this paper, we study the boundedness of the fractional integral operator and their commutator on Herz spaecs with two variable exponents . By using the properties of the variable exponents Lebesgue spaces, the boundedness of the fractional integral operator and their commutator generated by Lipschitz function is obtained on those Herz spaces. 展开更多
关键词 fractional integral Variable Kernel COMMUTATOR Variable Exponent Lipschitz Space Herz Spaces
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First Integral Method: A General Formula for Nonlinear Fractional Klein-Gordon Equation Using Advanced Computing Language 被引量:3
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作者 Mohamed A. Abdoon 《American Journal of Computational Mathematics》 2015年第2期127-134,共8页
In this article, a general formula of the first integral method has been extended to celebrate the exact solution of nonlinear time-space differential equations of fractional orders. The proposed method is easy, direc... In this article, a general formula of the first integral method has been extended to celebrate the exact solution of nonlinear time-space differential equations of fractional orders. The proposed method is easy, direct and concise as compared with other existent methods. 展开更多
关键词 First integral Method EXACT Solution fractional KLEIN-GORDON Equation
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Numerical Methods for Solving Space Fractional Partial Differential Equations Using Hadamard Finite-Part Integral Approach 被引量:1
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作者 Yanyong Wang Yubin Yan Ye Hu 《Communications on Applied Mathematics and Computation》 2019年第4期505-523,共19页
We introduce a novel numerical method for solving two-sided space fractional partial differential equations in two-dimensional case.The approximation of the space fractional Riemann-Liouville derivative is based on th... We introduce a novel numerical method for solving two-sided space fractional partial differential equations in two-dimensional case.The approximation of the space fractional Riemann-Liouville derivative is based on the approximation of the Hadamard finite-part integral which has the convergence order O(h^3-a),where h is the space step size and α∈(1,2)is the order of Riemann-Liouville fractional derivative.Based on this scheme,we introduce a shifted finite difference method for solving space fractional partial differential equations.We obtained the error estimates with the convergence orders O(τ+h^3-a+h^β),where τ is the time step size and β>0 is a parameter which measures the smoothness of the fractional derivatives of the solution of the equation.Unlike the numerical methods for solving space fractional partial differential equations constructed using the standard shifted Griinwald-Letnikov formula or higher order Lubich's methods which require the solution of the equation to satisfy the homogeneous Dirichlet boundary condition to get the firstorder convergence,the numerical method for solving the space fractional partial differential equation constructed using the Hadamard finite-part integral approach does not require the solution of the equation to satisfy the Dirichlet homogeneous boundary condition.Numerical results show that the experimentally determined convergence order obtained using the Hadamard finite-part integral approach for solving the space fractional partial differential equation with non-homogeneous Dirichlet boundary conditions is indeed higher than the convergence order obtained using the numerical methods constructed with the standard shifted Griinwald-Letnikov formula or Lubich's higher order approximation schemes. 展开更多
关键词 riemann-liouville fractional derivative SPACE fractional partial differential equation Error ESTIMATES
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Study for System of Nonlinear Differential Equations with Riemann-Liouville Fractional Derivative 被引量:1
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作者 Yanping Zheng Wenxia Wang 《Applied Mathematics》 2013年第7期5-8,共4页
In this work, we study existence theorem of the initial value problem for the system of fractional differential equations where Dα denotes standard Riemann-Liouville fractional derivative, 0 and A ?is a square matrix... In this work, we study existence theorem of the initial value problem for the system of fractional differential equations where Dα denotes standard Riemann-Liouville fractional derivative, 0 and A ?is a square matrix. At the same time, power-type estimate for them has been given. 展开更多
关键词 riemann-liouville fractional DERIVATIVE WEIGHTED Cauchy-Type Problem fractional Differential EQUATIONS
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Lipschitz estimates for commutator of fractional integral operators on non-homogeneous metric measure spaces 被引量:1
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作者 WANG Ding-huai ZHOU Jiang MA Bo-lin 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2020年第3期253-264,共12页
In this paper, the authors establish the(L^p(μ), L^q(μ))-type estimate for fractional commutator generated by fractional integral operators Tα with Lipschitz functions(b ∈ Lipβ(μ)),where 1 < p < 1/(α + β... In this paper, the authors establish the(L^p(μ), L^q(μ))-type estimate for fractional commutator generated by fractional integral operators Tα with Lipschitz functions(b ∈ Lipβ(μ)),where 1 < p < 1/(α + β) and 1/q = 1/p-(α + β), and obtain their weak(L^1(μ), L^(1/(1-α-β))(μ))-type. Moreover, the authors also consider the boundedness in the case that 1/(α+β) < p < 1/α,1/α≤ p ≤∞ and the endpoint cases, namely, p = 1/(α + β). 展开更多
关键词 Non-homogeneous space fractional integral Lipschitz function COMMUTATOR Endpoint estimate
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The Boundedness of Fractional Integral with Variable Kernel on Variable Exponent Herz-Morrey Spaces 被引量:2
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作者 Afif Abdalmonem Omer Abdalrhman Shuangping Tao 《Journal of Applied Mathematics and Physics》 2016年第4期787-795,共9页
In this paper, we study the boundedness of the fractional integral with variable kernel. Under some assumptions, we prove that such kind of operators is bounded from the variable exponent Herz-Morrey spaces to the var... In this paper, we study the boundedness of the fractional integral with variable kernel. Under some assumptions, we prove that such kind of operators is bounded from the variable exponent Herz-Morrey spaces to the variable exponent Herz-Morrey spaces. 展开更多
关键词 fractional integral Variable Kernel Variable Exponent Herz-Morrey Spaces
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Boundedness of fractional integral operators on α-modulation spaces 被引量:3
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作者 WU Xiao-mei CHEN Jie-cheng 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2014年第3期339-351,共13页
In this paper, we obtain the boundedness of the fractional integral operators, the bilinear fractional integral operators and the bilinear Hilbert transform on α-modulation spaces.
关键词 有界性 分算 分数 空间 调制 希尔伯特变换 双线性
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