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On n-K Width of Certain Function Classes Defined by Linear Differential Operators in L_2 Space
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作者 吴嘎日迪 包那 《Chinese Quarterly Journal of Mathematics》 CSCD 1999年第4期27-31, ,共5页
Let M(u) be an N function, A=D r+∑r-1k=0a k(x)D k a linear differential operator and W M(A) the Sobolev Orlicz class defined by M(u) and A. In this paper we give the asymptotic estimates... Let M(u) be an N function, A=D r+∑r-1k=0a k(x)D k a linear differential operator and W M(A) the Sobolev Orlicz class defined by M(u) and A. In this paper we give the asymptotic estimates of the n K width d n(W M(A),L 2[0,1]) . 展开更多
关键词 linear operator smooth function class WIDTH
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On n-K Width of Certain Function Classes Defined by Linear Differential Operators in L2 Space 被引量:2
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作者 吴嘎日迪 包那 《Chinese Quarterly Journal of Mathematics》 CSCD 1999年第4期27-31,共页
Let M(u) be an N function, A=D r+∑r-1k=0a k(x)D k a linear differential operator and W M(A) the Sobolev Orlicz class defined by M(u) and A. In this paper we give the asymptotic estimates... Let M(u) be an N function, A=D r+∑r-1k=0a k(x)D k a linear differential operator and W M(A) the Sobolev Orlicz class defined by M(u) and A. In this paper we give the asymptotic estimates of the n K width d n(W M(A),L 2[0,1]) . 展开更多
关键词 linear operator smooth function class WIDTH
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MNTZ RATIONAL APPROXIMATION FOR SPECIAL FUNCTION CLASSES IN Ba[0,1] SPACES
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作者 Zhenghua Kang Garidi Wu 《Analysis in Theory and Applications》 2012年第1期87-94,共8页
In this paper, we research the Miintz rational approximation of two kinds of spe- cial function classes, and give the corresponding estimates of approximation rates of these classes.
关键词 Muntz rational approximation bounded variation function class Sobolevfunction class approximation rate
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Muntz Rational Approximation for Special Function Classes in Orlicz Spaces 被引量:1
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作者 Ruifang Yu Garide Wu 《Analysis in Theory and Applications》 CSCD 2017年第1期20-28,共9页
Using the method of construction, with the help of inequalities, we research the Muntz rational approximation of two kinds of special function classes, and give the corresponding estimates of approximation rates of th... Using the method of construction, with the help of inequalities, we research the Muntz rational approximation of two kinds of special function classes, and give the corresponding estimates of approximation rates of these classes under widely con- ditions. Because of the Orlicz Spaces is bigger than continuous function space and the Lp space, so the results of this paper has a certain expansion significance. 展开更多
关键词 Muntz rational approximation bounded variation function class Sobolev functionclass Orlicz space.
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AVERAGE σ-K WIDTH OF CONVOLUTION FUNCTION CLASS OF L_(pq) (R) IN L_q(R)
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作者 Liu Yongping Beijing Normal University. Beijing 《Analysis in Theory and Applications》 1994年第1期34-46,共13页
In this paper. we study the average n-K width of the convolution class B_(pq)(G)(or B_(?)(G)), for which the kernel G(x) is a PF density, in the metric L_q(R)(or L_(qp)(R)) for the case 1≤q<p ≤∞, and obtain some... In this paper. we study the average n-K width of the convolution class B_(pq)(G)(or B_(?)(G)), for which the kernel G(x) is a PF density, in the metric L_q(R)(or L_(qp)(R)) for the case 1≤q<p ≤∞, and obtain some exact results. 展开更多
关键词 IN L_q K WIDTH OF CONVOLUTION function class OF L PQ AVERAGE Math
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Existence of Solutions for Volterra Singular Integral Equations in the Class of Exponentially Increasing Functions
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作者 ZHANG Wen-wen LI Ping-run 《Chinese Quarterly Journal of Mathematics》 2025年第2期135-147,共13页
The goal of this paper is to investigate the theory of Noether solvability for Volterra singular integral equations(VSIEs)with convolution and Cauchy kernels in a more general function class.To obtain the analytic sol... The goal of this paper is to investigate the theory of Noether solvability for Volterra singular integral equations(VSIEs)with convolution and Cauchy kernels in a more general function class.To obtain the analytic solutions,we transform such equations into boundary value problems with discontinuous coefficients by the properties of Fourier analysis.In view of the analytical Riemann-Hilbert method,the generalized Liouville theorem and Sokhotski-Plemelj formula,we get the uniqueness and existence of solutions for such problems,and study the asymptotic property of solutions at nodes.Therefore,this paper improves the theory of singular integral equations and boundary value problems. 展开更多
关键词 Volterra singular integral equations The theory of Noether solvability The class of exponentially increasing functions Riemann-Hilbert method
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Chronic heart failure with reduced and mildly reduced left ventricle ejection fraction:relationship between mitochondrial respiratory dysfunction of peripheral blood mononuclear cells and iron deficiency
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作者 Alla A Garganeeva Viacheslav A.Korepanov +4 位作者 Elena A Kuzheleva Olga V Tukish Karina N Vitt Elvira F Muslimova Sergey A Afanasiev 《Journal of Geriatric Cardiology》 2025年第9期812-817,共6页
Objectives To compare respiratory parameters of peripheral blood mononuclear cell mitochondria and iron metabolism indicators in patients with different NYHA functional classes of ischemic heart failure(HF).Methods Th... Objectives To compare respiratory parameters of peripheral blood mononuclear cell mitochondria and iron metabolism indicators in patients with different NYHA functional classes of ischemic heart failure(HF).Methods This single center, prospective, non-blinded study enrolled 20 patients with diagnosed chronic HF of ischemic genesis with reduced and mildly reduced left ventricle ejection fraction. The maximum oxygen consumption at the peak of the exercise test(VO2peak), iron metabolism parameters and respiratory activity of peripheral blood mononuclear cell mitochondria were assessed.Results Among the patients, a half of individuals were diagnosed with iron deficiency. Subgroups of patients with different HF severity did not significant differ in VO2peak(P=0.209), serum iron(P=0.468) and ferritin(P=0.235) levels. But there was a trend in increasing in these parameters with increasing NYHA HF functional class. Respiratory control coefficient(RC) in NADdependent and FAD-dependent mitochondrial oxidation were lower in patients with NYHA HF Ⅲ functional class compared to individuals with NYHA HF I functional class(P=0.028 and P=0.040, respectively). Serum iron(P=0.026), ferritin(P=0.045)levels, transferrin saturation(P=0.006) were negatively correlated with RC in NAD-dependent mitochondrial oxidation.Conclusions In aggravation of ischemic HF NYHA FC, there is a decrease in RC of PBMC mitochondria during the oxidation of NAD-dependent and FAD-dependent substrates. In the whole sample, patients with laboratory-confirmed iron deficiency accounted a half of the total number. Iron metabolism parameters had a paradoxical inverse relationship with the level of RC in PBMC mitochondria of patients with HF. 展开更多
关键词 metabolism parameters nyha functional classes peripheral blood mononuclear cell mitochondria respiratory parameters maximum oxygen iron metabolism indicators Chronic Heart Failure ischemic heart failure hf methods
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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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RELATIVE WIDTH OF SMOOTH CLASSES OF MULTIVARIATE PERIODIC FUNCTIONS WITH RESTRICTIONS ON ITERATED LAPLACE DERIVATIVES IN THE L_2-METRIC 被引量:1
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作者 刘永平 杨连红 《Acta Mathematica Scientia》 SCIE CSCD 2006年第4期720-728,共9页
For two subsets W and V of a Banach space X, let Kn(W, V, X) denote the relative Kolmogorov n-width of W relative to V defined by Kn(W,V,X):=inf sup inf/Ln f∈W g∈V∩Ln‖f-g‖x, where the infimum is taken over ... For two subsets W and V of a Banach space X, let Kn(W, V, X) denote the relative Kolmogorov n-width of W relative to V defined by Kn(W,V,X):=inf sup inf/Ln f∈W g∈V∩Ln‖f-g‖x, where the infimum is taken over all n-dimensional linear subspaces Ln of X. Let W2(△^τ) denote the class of 2π-periodic functions f with d-variables satisfying ∫[-π, π]^d|△^τf(x)|^2dx≤1, while △^τ is the r-iterate of Laplace operator △. This article discusses the relative Kolmogorov n-width of W2(△^τ) relative to W2(△^τ) in Lq([-π, π]^d) (1≤ q ≤ ∞), and obtain its weak asymptotic result. 展开更多
关键词 Multivariate function classes WIDTH relative width
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HAAR EXPANSIONS OF A CLASS OF FRACTAL INTERPOLATION FUNCTIONS AND THEIR LOGICAL DERIVATIVES 被引量:1
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作者 Sha Zhen Chen Gang Zhejiang University,China 《Analysis in Theory and Applications》 1993年第4期73-88,共16页
In this paper,we study a special class of fractal interpolation functions,and give their Haar-wavelet expansions.On the basis of the expansions,we investigate the H(o|¨)lder smoothness of such functions and their... In this paper,we study a special class of fractal interpolation functions,and give their Haar-wavelet expansions.On the basis of the expansions,we investigate the H(o|¨)lder smoothness of such functions and their logical derivatives of order α. 展开更多
关键词 HAAR EXPANSIONS OF A class OF FRACTAL INTERPOLATION functionS AND THEIR LOGICAL DERIVATIVES der HAAR FIF
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Correlation between the Six-Minute Walk Test and Subjective Functional Class in Patients with Heart Failure
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作者 Davi Muzi Rios Gabriela Lira Devens +10 位作者 Leticia Admiral Louzada Priscila Cabral Gomes Coelho Lima Rodolfo Costa Sylvestre Vinicius Angelo Astolpho Lucas Crespo de Barros Larissa Novaes Paganini Lucas Martins Frizzera Borges Renato Giestas Serpa Osmar Araujo Calil Luiz Fernando Machado Barbosa Roberto Ramos Barbosa 《World Journal of Cardiovascular Diseases》 CAS 2023年第4期205-213,共9页
Introduction: The Six-Minute Walk Test (6MWT) is an inexpensive method to objectively evaluate physical capacity or limitation and stratify prognosis in patients with Heart Failure (HF). Since the clinical p... Introduction: The Six-Minute Walk Test (6MWT) is an inexpensive method to objectively evaluate physical capacity or limitation and stratify prognosis in patients with Heart Failure (HF). Since the clinical perception of symptoms may be adapted or compromised, regular evaluation from medical interviews often fails to determine functional classification. This study aimed to assess the correlation between New York Heart Association Functional Class (NYHA-FC) and the distance walked in the 6MWT. Methods: We conducted a cross-sectional observational study that included patients with HF with reduced ejection fraction followed up at an outpatient service of a teaching hospital, from August 2018 to April 2019. Patients in NYHA-FC I, II, or III were included. We compared NYHA-FC subjectively obtained during the consultation with the 6MWT performed after medical consultation, and the correlation between these two parameters was assessed. Results: The study included 70 patients with HF, 41 (58.6%) of whom were female. The mean age was 61.2 ± 12.7 years. The most prevalent etiologies were dilated idiopathic cardiomyopathy (35.7%) followed by ischemic cardiomyopathy (25.7%). The mean ejection fraction was 34.1% ± 9.8%. The average distance walked in the 6MWT by NYHA-FC I patients was 437.8 ± 95.8 meters, NYHA-FC II 360.1 ± 96.4, and NYHA-FC III 248.4 ± 98.3. Functional class measured by the 6MWT was different than that estimated by NYHA-FC in 34 patients (48.6%), 23 (32.9%) for a higher functional class and 11 (15.7%) for a lower one (p = 0.07). Pearson’s correlation coefficient between NYHA-FC and the 6MWT was -0.55. Conclusion: There was a moderate correlation between the subjective NYHA-FC and the 6MWT. The 6MWT revealed a different classification from NYHA-FC in almost half of the patients. Among those who presented discrepancies between methods, 6MWT reclassification towards a higher functional class was more common. 展开更多
关键词 Heart Failure Six-Minute Walk Test functional class
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CONVERGENCE OF A CLASS OF MEANS OF H^p FUNCTIONS(0 被引量:1
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作者 Wang Jiwen Anhui University,China 《Analysis in Theory and Applications》 1993年第4期37-45,共9页
In this paper we study the convergence nf a class of means on H^p(G)(0<p<1),the means take the Bochner-Riesz means in[1],the generalized Bochner-Riesz means in[2],and the operators T^(Φ_r)in[3]as special cases.... In this paper we study the convergence nf a class of means on H^p(G)(0<p<1),the means take the Bochner-Riesz means in[1],the generalized Bochner-Riesz means in[2],and the operators T^(Φ_r)in[3]as special cases.We obtain weak-type estimates for the associated maximal operators and the maximal mean boundedness for the means. 展开更多
关键词 exp p<1)ON COMPACT LIE GROUPS CONVERGENCE OF A class OF MEANS OF H~p functionS
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APPROXIMATION BY FABER-LAURENT RATIONAL FUNCTIONS IN THE MEAN OF FUNCTIONS OF CLASS LP(T) WITH 1
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作者 A. Cavus D. M. Israfilov 《Analysis in Theory and Applications》 1995年第1期105-118,共14页
Let Γ be a regular curve and Lp (Γ), 1<p<+∞. be the class of all complex - valued functions f de-fined on Γ which are such that |f|p is mtegrabie in sense of Lebesgue. In this work, we define the k th p-Fabc... Let Γ be a regular curve and Lp (Γ), 1<p<+∞. be the class of all complex - valued functions f de-fined on Γ which are such that |f|p is mtegrabie in sense of Lebesgue. In this work, we define the k th p-Fabcrpolynomial F k,p (z),the kth p-Faber principle part F k.p (1/z) for Γ , and defined the nth p-Fcber- Laurent rational function Rn.p (f, z) and p- generalized modulus of continuity Ωp(f, t) of a function f of Lp(Γ) We inves-tigate some properties of Fk,p (z) and Fk.p (1/z). And then we prove a direct theorem characterizing the degree of approximation with respect to Ω (. , t) in the mean of functions of Lp(Γ) by the rational junctions Rn.p (. . z). 展开更多
关键词 APPROXIMATION BY FABER-LAURENT RATIONAL functionS IN THE MEAN OF functionS OF class LP WITH 1 Rational
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Comparison of skeletal, dental and soft tissue changes in young adults with Class II malocclusion, treated either by camouflage, fixed functional appliance or orthognathic surgery—A prospective study on Indian subjects 被引量:1
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作者 Anjana Shetty Anand Patil Sanjay Ganeshkar 《Open Journal of Stomatology》 2012年第4期373-382,共10页
Introduction: Borderline Class II malocclusion due to deficient mandible can be treated either by orthodontic camouflage, fixed functional appliances or by orthodontics followed by surgical mandibular advancement. Met... Introduction: Borderline Class II malocclusion due to deficient mandible can be treated either by orthodontic camouflage, fixed functional appliances or by orthodontics followed by surgical mandibular advancement. Methodology: A prospective study was designed on young adults with Class II malocclusion on account of a deficient mandible. A total of 45 subjects were divided into three groups of 15 individuals each. The patients were treated either by camouflage, fixed functional appliances or by orthognathic surgery. Pre and post treatment cephalograms were used to assess the skeletal, dental and soft tissue changes. Pre and post treatment profile photographs were assessed on a Visual Analogue Scale (VAS) by orthodontists, oral surgeons and laypersons. Results: Each group achieved a reduction in facial convexity, but the results obtained from the surgical group were more pronounced than the camouflage and the fixed functional group. Conclusion: The reduction in convexity in the camouflage group was by retracting the upper anteriors, which increases the nasolabial angle. In the fixed functional appliance a combination of skeletal and dentoalveolar changes can be observed. However the most appropriate reduction in profile convexity can be obtained by combined orthodontic and surgical treatment of malocclusion. 展开更多
关键词 class II Malocclulsion CAMOUFLAGE Fixed function APPLIANCE ORTHOGNATHIC Surgery
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Basic Functions for Computational Implementation of the Box-Cox Symmetric Class of Distributions
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作者 Giovana Fumes-Ghantous José Eduardo Corrente 《Open Journal of Statistics》 2021年第6期1010-1016,共7页
A class of distributions called Box-Cox symmetric was proposed for random variables with asymmetric distributions. This class allows through its structure an interpretation of the parameters in terms of quantiles (in ... A class of distributions called Box-Cox symmetric was proposed for random variables with asymmetric distributions. This class allows through its structure an interpretation of the parameters in terms of quantiles (in particular, the median), relative dispersion and skewness. This study presents the initial </span><span style="font-family:Verdana;">results of the computational development of basic functions of each of the</span><span style="font-family:Verdana;"> distributions that make up the Box-Cox symmetric class. Four functions have been developed to compose a routine in software R up to now. These functions are related to random numbers generation, probability density function, cumulative distribution function, and quantile function associated to a given probability. Examples of implemented functions were presented. The gamlss routine was used to check the performance of developed functions. 展开更多
关键词 Asymmetric Distributions Basic functions Box-Cox Symmetric class
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新时代国有企业核心竞争力的构成要素、现实基础与提升方略 被引量:5
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作者 王欣 王梅知 《改革》 北大核心 2025年第2期49-61,共13页
新时代国有企业提升核心竞争力对于有效增强国有企业核心功能、促进国有经济高质量发展、加快建设世界一流企业具有重要战略价值和意义。新时代国有企业核心竞争力的构成要素主要包括战略资源配置能力、原始技术创新能力、现代化治理能... 新时代国有企业提升核心竞争力对于有效增强国有企业核心功能、促进国有经济高质量发展、加快建设世界一流企业具有重要战略价值和意义。新时代国有企业核心竞争力的构成要素主要包括战略资源配置能力、原始技术创新能力、现代化治理能力、数字化运营能力和品牌国际影响力。党的十八大以来,中央不断完善深化国有企业改革的政策措施并开展了“科改示范”、管理提升和价值创造等系列专项行动,国有企业核心竞争力得到显著提升,但与世界一流企业相比仍然存在一定差距。新时代国有企业核心竞争力的提升应着眼于以下方面:以提高整体效率为目标,加强统筹战略资源优化配置;以原始技术突破为驱动,全面激发企业创新发展动能;以打造现代新国企为指引,提升企业现代化治理水平;以推动数字化转型为抓手,促进数字赋能高质量发展;以提升品牌影响力为导向,加快建设更多世界一流企业。 展开更多
关键词 国有企业 核心竞争力 核心功能 世界一流企业
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黎曼积分的扩充
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作者 郑永树 伍锦棠 《大学数学》 2025年第2期89-94,共6页
运用集合论和勒贝格测度论的结果,对“黎曼和”进行修改,把黎曼积分对象扩充到可测函数类.在黎曼修改型积分定义的基础上,证明可测函数的可积性,以及其积分值与勒贝格积分的积分值相等.
关键词 黎曼积分的扩充 “黎曼和”修改模型 黎曼修改型积分 可测函数类
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Polar Functions for Fractional Brownian Motion
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作者 肖益民 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第1期76-80,共5页
Let X (t)(t∈R^N) be a d-dimensional fractional Brownian motion. A contiunous function f:R^N→R^d is called a polar function of X(t)(t∈R^N) if P{ t∈R^N\{0},X(t)=t(t)}=0. In this paper, the characteristies of the cla... Let X (t)(t∈R^N) be a d-dimensional fractional Brownian motion. A contiunous function f:R^N→R^d is called a polar function of X(t)(t∈R^N) if P{ t∈R^N\{0},X(t)=t(t)}=0. In this paper, the characteristies of the class of polar functions are studied. Our theorem 1 improves the previous results of Graversen and Legall. Theorem2 solves a problem of Legall (1987) on Brownian motion. 展开更多
关键词 fractional Brownian motion polar function Lipschitz function class quasi-helix Hausdorff dimension
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关于Euler gamma函数Γ与一类L-函数的代数微分无关性
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作者 李效敏 李奕萱 《中国海洋大学学报(自然科学版)》 北大核心 2025年第S1期106-109,148,共5页
本文研究了Euler gamma函数Γ与满足公理(Ⅰ)—(Ⅴ)的L-函数类S中的L-函数的代数微分无关性问题,证明了S中的L-函数与Euler gamma函数Γ不满足任意给定的非平凡代数微分方程。本文的主要结果推广了李宝勤和叶专2016年的相应结果,改进了... 本文研究了Euler gamma函数Γ与满足公理(Ⅰ)—(Ⅴ)的L-函数类S中的L-函数的代数微分无关性问题,证明了S中的L-函数与Euler gamma函数Γ不满足任意给定的非平凡代数微分方程。本文的主要结果推广了李宝勤和叶专2016年的相应结果,改进了陈玮和王琼2021年的相应结果。 展开更多
关键词 Euler gamma函数Γ L-函数类S 微分无关性 代数微分方程
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GENERALIZED FRACTIONAL CALCULUS OF THE ALEPH-FUNCTION INVOLVING A GENERAL CLASS OF POLYNOMIALS
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作者 R.K.SAXENA D.KUMAR 《Acta Mathematica Scientia》 SCIE CSCD 2015年第5期1095-1110,共16页
The object of this article is to study and develop the generalized fractional calcu- lus operators given by Saigo and Maeda in 1996. We establish generalized fractional calculus formulas involving the product of R-fun... The object of this article is to study and develop the generalized fractional calcu- lus operators given by Saigo and Maeda in 1996. We establish generalized fractional calculus formulas involving the product of R-function, Appell function F3 and a general class of poly- nomials. The results obtained provide unification and extension of the results given by Saxena et al. [13], Srivastava and Grag [17], Srivastava et al. [20], and etc. The results are obtained in compact form and are useful in preparing some tables of operators of fractional calculus. On account of the general nature of the Saigo-Maeda operators, R-function, and a general class of polynomials a large number of new and known results involving Saigo fractional calculus operators and several special functions notably H-function, /-function, Mittag-Leffier function, generalized Wright hypergeometric function, generalized Bessel-Maitland function follow as special cases of our main findings. 展开更多
关键词 generalized fractional calculus operators a general class of polynomials R-function H-function /-function generalized Wright hypergeometric function Mittag-Leffler function generalized Bessel-Maitland function
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