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边加权有限图的Weil-Riemann-Roch定理
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作者 曹廷彬 刘洁 《南昌大学学报(理科版)》 CAS 2024年第2期103-107,共5页
Riemann-Roch定理是数学中的一个重要结论,并有了广泛的应用。在有限图和边加权有限图等图中也有对应的Riemann-Roch定理以及应用,但所有这些工作都有一个共同点,那就是它们都聚焦于在除子或和除子线性等价的线丛的情况下,也就是秩为1... Riemann-Roch定理是数学中的一个重要结论,并有了广泛的应用。在有限图和边加权有限图等图中也有对应的Riemann-Roch定理以及应用,但所有这些工作都有一个共同点,那就是它们都聚焦于在除子或和除子线性等价的线丛的情况下,也就是秩为1的情况。为了得到高维秩的情形,可以借助多重除子的术语来描述。本文利用还原群GLn的root datum的概念给出了边加权有限图上主GLn-丛——向量丛的定义,并用多重除子的术语来描述向量丛,进而给出了边加权有限图的Weil-Riemann-Roch定理以及证明,推广了GROSS A.ULIRSCH M.和ZAKHAROV D的结果。 展开更多
关键词 边加权有限图 riemann-Roch定理 向量丛 多重除子
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DISTORTION THEOREMS FOR CLASSES OF g-PARAMETRIC STARLIKE MAPPINGS OF REAL ORDER IN C^(n)
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作者 刘红炎 涂振汉 熊良鹏 《Acta Mathematica Scientia》 SCIE CSCD 2023年第4期1491-1502,共12页
In this paper,we define the class S_(g)^(BX)of g-parametric starlike mappings of real order γ on the unit ball BX in a complex Banach space X,where g is analytic and satisfies certain conditions.By establishing the d... In this paper,we define the class S_(g)^(BX)of g-parametric starlike mappings of real order γ on the unit ball BX in a complex Banach space X,where g is analytic and satisfies certain conditions.By establishing the distortion theorem of the Fr´echet-derivative type of S_(g)^(BX)with a weak restrictive condition,we further obtain the distortion results of the Jacobi-determinant type and the Fr´echet-derivative type for the corresponding classes(compared with S_(g)^(BX))defined on the unit polydisc(resp.unit ball with the arbitrary norm)in the space of n-dimensional complex variables,n≥2.Our results extend the classic distortion theorem of holomorphic functions from the case in one-dimensional complex space to the case in the higher dimensional complex space.The main theorems also generalize and improve some recent works. 展开更多
关键词 Banach space distortion theorem of Jacobi-determinant type distortion theorems of the Frechet-derivative type g-parametric starlike mappings
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A fixed point theorem for Proinov mappings with a contractive iterate
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作者 Erdal Karapnar Andreea Fulga 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2023年第3期403-412,共10页
In this paper,we consider the fixed point theorem for Proinov mappings with a contractive iterate at a point.In other words,we combine and unify the basic approaches of Proinov and Sehgal in the framework of the compl... In this paper,we consider the fixed point theorem for Proinov mappings with a contractive iterate at a point.In other words,we combine and unify the basic approaches of Proinov and Sehgal in the framework of the complete metric spaces.We consider examples to illustrate the validity of the obtained result. 展开更多
关键词 contractive iterate at a point Proinov mappings fixed point theorems
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ESTIMATE ON THE BLOCH CONSTANT FOR CERTAIN HARMONIC MAPPINGS UNDER A DIFFERENTIAL OPERATOR
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作者 陈洁玲 刘名生 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期295-310,共16页
In this paper,we first obtain the precise values of the univalent radius and the Bloch constant for harmonic mappings of the formL(f)=zfz-zfz,where f represents normalized harmonic mappings with bounded dilation.Then,... In this paper,we first obtain the precise values of the univalent radius and the Bloch constant for harmonic mappings of the formL(f)=zfz-zfz,where f represents normalized harmonic mappings with bounded dilation.Then,using these results,we present better estimations for the Bloch constants of certain harmonic mappings L(f),where f is a K-quasiregular harmonic or open harmonic.Finally,we establish three versions of BlochLandau type theorem for biharmonic mappings of the form L(f).These results are sharp in some given cases and improve the related results of earlier authors. 展开更多
关键词 Bloch-Landau type theorem Bloch constant linear complex operator harmonic mapping biharmonic mapping UNIVALENT
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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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The Growth Theorem for Almost Starlike Mappings of Order α on Bounded Starlike Circular Domains 被引量:3
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作者 冯淑霞 卢克平 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第2期50-56,共7页
In this paper,we extend the definition of almost starlike mappings of order 1/2 on B n to the almost starlike mappings of order α on the bounded starlike circular domains in C n,and give the growth theorem of it.... In this paper,we extend the definition of almost starlike mappings of order 1/2 on B n to the almost starlike mappings of order α on the bounded starlike circular domains in C n,and give the growth theorem of it. This type of domain on which we discuss is rather general,in the sense that the domain must be starlike if there exists a normalized biholomorphic starlike mapping on it. 展开更多
关键词 almost starlike mapping of order α growth theorem starlike circular domains
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The Growth Theorem for Strongly Starlike Mappings of Order α on Bounded Starlike Circular Domains
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作者 刘浩 李小申 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第3期28-33,共6页
The authors obtain the growth and covering theorems for strongly starlike mappings of order α on bounded starlike circular domains.This kind of domain discussed is rather general,since the domain must be starlike if ... The authors obtain the growth and covering theorems for strongly starlike mappings of order α on bounded starlike circular domains.This kind of domain discussed is rather general,since the domain must be starlike if exists a normalized biholomorphic starlike mapping on it. 展开更多
关键词 strongly starlike mappings of order α growth theorem startike circular domains
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Noether's theorems of a fractional Birkhoffian system within Riemann-Liouville derivatives 被引量:17
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作者 周燕 张毅 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第12期281-288,共8页
The Noether symmetry and the conserved quantity of a fractional Birkhoffian system are studied within the Riemann–Liouville fractional derivatives. Firstly, the fractional Birkhoff's equations and the corresponding ... The Noether symmetry and the conserved quantity of a fractional Birkhoffian system are studied within the Riemann–Liouville fractional derivatives. Firstly, the fractional Birkhoff's equations and the corresponding transversality conditions are given. Secondly, from special to general forms, Noether's theorems of a standard Birhoffian system are given, which provide an approach and theoretical basis for the further research on the Noether symmetry of the fractional Birkhoffian system. Thirdly, the invariances of the fractional Pfaffian action under a special one-parameter group of infinitesimal transformations without transforming the time and a general one-parameter group of infinitesimal transformations with transforming the time are studied, respectively, and the corresponding Noether's theorems are established. Finally, an example is given to illustrate the application of the results. 展开更多
关键词 fractional Birkhoffian system Noether's theorem fractional conserved quantity riemann–Liouville fractional derivative
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DISTORTION THEOREMS FOR SUBCLASSES OF STARLIKE MAPPINGS ALONG A UNIT DIRECTION IN C^n 被引量:4
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作者 卢金 刘太顺 王建飞 《Acta Mathematica Scientia》 SCIE CSCD 2012年第4期1675-1680,共6页
In this paper, we obtain a distortion theorem of Jacobian matrix for biholomorphic subclasses of starlike mappings along a unit direction on the unit polydisc. These results extend the classical distortion theorem of ... In this paper, we obtain a distortion theorem of Jacobian matrix for biholomorphic subclasses of starlike mappings along a unit direction on the unit polydisc. These results extend the classical distortion theorem of starlike mappings to higher dimensions. We then give an upper bound estimate for biholomorphic subclasses of starlike mappings along a unit direction in a complex Banach space. 展开更多
关键词 subclasses of starlike mappings distortion theorem Banach space growththeorem
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GROWTH AND DISTORTION THEOREMS FOR ALMOST STARLIKE MAPPINGS OF COMPLEX ORDER λ 被引量:3
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作者 Xiaofei ZHANG Jin LU Xiaofei LI 《Acta Mathematica Scientia》 SCIE CSCD 2018年第3期769-777,共9页
In this article, the sharp growth theorem for almost starlike mappings of complex order λ is given firstly. Secondly, distortion theorem along a unit direction is also established as the application of the growth the... In this article, the sharp growth theorem for almost starlike mappings of complex order λ is given firstly. Secondly, distortion theorem along a unit direction is also established as the application of the growth theorem. In particular, using our results can reduce to some well-known results. 展开更多
关键词 Distortion theorem convex mapping Schwarz lemma at the boundary
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ON THE SHARP GROWTH,COVERING THEOREMS FOR NORMALIZED BIHOLOMORPHIC MAPPINGS IN C^n 被引量:2
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作者 刘小松 刘太顺 《Acta Mathematica Scientia》 SCIE CSCD 2007年第4期803-812,共10页
In this article, a normalized biholomorphic mapping f defined on bounded starlike circular domain in Cn is considered, where z = 0 is a zero of order k + 1 of f(z) - z. The sharp growth, covering theorems for almos... In this article, a normalized biholomorphic mapping f defined on bounded starlike circular domain in Cn is considered, where z = 0 is a zero of order k + 1 of f(z) - z. The sharp growth, covering theorems for almost starlike mappings of order α and starlike mappings of order α are established. Meanwhile, the construction of the above mappings on bounded starlike circular domain in Cn is also discussed, it provides the extremal mappings for the growth, covering theorems of the above mappings. 展开更多
关键词 Zero of order k 1 normalized biholomorphic mappings almost starlike mappings of order α starlike mappings of order α GROWTH covering theorems
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A DEGENERACY THEOREM FOR MEROMORPHIC MAPPINGS WITH TRUNCATED MULTIPLICITIES 被引量:2
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作者 颜启明 陈志华 《Acta Mathematica Scientia》 SCIE CSCD 2011年第2期549-560,共12页
In this article, we prove a degeneracy theorem for three linearly non-degenerate meromorphic mappings from Cn into PN (C), sharing 2N + 2 hyperplanes in general position, counted with multiplicities truncated by 2.
关键词 Value distribution theory degeneracy theorem meromorphic mapping
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COINCIDENCE THEOREMS INVOKING COMPOSITES OF ACYCLIC MAPPINGS AND APPLICATIONS 被引量:2
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作者 丁协平 《Acta Mathematica Scientia》 SCIE CSCD 1999年第1期53-61,共9页
Some new coincidence theorems involving a new class of set-valued mappingscontaining composites of acyclic mappings defined on a contractible space are proved.As applications, some existence theorems of maximal elemen... Some new coincidence theorems involving a new class of set-valued mappingscontaining composites of acyclic mappings defined on a contractible space are proved.As applications, some existence theorems of maximal elements and solutions of abstract variational inequalities, and best approximation theorems are proved. These theorems improve and generalize a number of known results in recent literature. 展开更多
关键词 Coincidence theorem maximal element variational inequality best approximation contractible space composites of acyclic mappings
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ELXED POINT THEOREM OF COMPOSITION g-CONTRACTION MAPPING AND ITS APPLICATIONS 被引量:1
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作者 YUN Tian-quan(云天铨) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2001年第10期1132-1139,共8页
Any composition sequential mapping, periodic composition mapping of a complete non-empty metric space M into M with geometric mean contraction ratio less than 1 ( simplifying as 'g-contraction mapping' ) has a... Any composition sequential mapping, periodic composition mapping of a complete non-empty metric space M into M with geometric mean contraction ratio less than 1 ( simplifying as 'g-contraction mapping' ) has a unique fixed point in M . Applications of the theorem to the proof of existence and uniqueness of the solutions of a set of non-linear differential equations and a coupled integral equations of symmetric bending of shallow shell of revolution are given. 展开更多
关键词 CONTRACTION mapping g-contraction mapping BANACH CONTRACTION mapping theorem functional analysis differential EQUATION integral EQUATION SHALLOW shell
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From the second gradient operator and second class of integral theorems to Gaussian or spherical mapping invariants 被引量:1
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作者 殷雅俊 吴继业 +1 位作者 黄克智 范钦珊 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2008年第7期855-862,共8页
By combining of the second gradient operator, the second class of integral theorems, the Gaussian-curvature-based integral theorems and the Gaussian (or spherical) mapping, a series of invariants or geometric conser... By combining of the second gradient operator, the second class of integral theorems, the Gaussian-curvature-based integral theorems and the Gaussian (or spherical) mapping, a series of invariants or geometric conservation quantities under Gaussian (or spherical) mapping are revealed. From these mapping invariants important transformations between original curved surface and the spherical surface are derived. The potential applications of these invariants and transformations to geometry are discussed 展开更多
关键词 the second gradient operator integral theorem Gaussian curvature Gaussian (or spherical) mapping mapping invariant
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Approach to a Proof of the Riemann Hypothesis by the Second Mean-Value Theorem of Calculus 被引量:3
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作者 Alfred Wünsche 《Advances in Pure Mathematics》 2016年第13期972-1021,共51页
By the second mean-value theorem of calculus (Gauss-Bonnet theorem) we prove that the class of functionswith an integral representation of the form  with a real-valued function which is non-increasing a... By the second mean-value theorem of calculus (Gauss-Bonnet theorem) we prove that the class of functionswith an integral representation of the form  with a real-valued function which is non-increasing and decreases in infinity more rapidly than any exponential functions , possesses zeros only on the imaginary axis. The Riemann zeta function  as it is known can be related to an entire functionwith the same non-trivial zeros as . Then after a trivial argument displacement we relate it to a function  with a representation of the form  where  is rapidly decreasing in infinity and satisfies all requirements necessary for the given proof of the position of its zeros on the imaginary axis z=iy by the second mean-value theorem. Besides this theorem we apply the Cauchy-Riemann differential equation in an integrated operator form derived in the Appendix B. All this means that we prove a theorem for zeros of  on the imaginary axis z=iy for a whole class of function  which includes in this way the proof of the Riemann hypothesis. This whole class includes, in particular, also the modified Bessel functions  for which it is known that their zeros lie on the imaginary axis and which affirms our conclusions that we intend to publish at another place. In the same way a class of almost-periodic functions to piece-wise constant non-increasing functions  belong also to this case. At the end we give shortly an equivalent way of a more formal description of the obtained results using the Mellin transform of functions with its variable substituted by an operator. 展开更多
关键词 riemann Hypothesis riemann Zeta Function Xi Function Gauss-Bonnet theorem Mellin Transformation
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On Growth and Covering Theorem for Almost Spiallike Mapping of Type β with Order α 被引量:2
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作者 刘爱超 崔志会 刘浩 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2005年第4期331-337,共7页
Let f(x) be an almost spirallike mapping of type β with order B on unit ball B of complex Banach space X. In this paper, we consider the growth and covering theorems for f(x), we also prove that the estimation is... Let f(x) be an almost spirallike mapping of type β with order B on unit ball B of complex Banach space X. In this paper, we consider the growth and covering theorems for f(x), we also prove that the estimation is precise when β=0 and still give growth upper bound and distortion upper bound for subordinate mapping. This result include some results known. 展开更多
关键词 spirallike mapping growth and covering theorem subordinate mapping
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The Distortion Theorems for k-fold Symmetric Quasi-convex Mappings along a Unit Direction in C^n 被引量:1
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作者 卢金 刘太顺 王建飞 《Chinese Quarterly Journal of Mathematics》 CSCD 2012年第4期475-479,共5页
We obtain a distortion theorem of Jacobian matrix Jf(z) for k-fold symmetric quasi-convex f along a unit direction in C^n on the unit polydisc.
关键词 quasi-convex mappings k-fold symmetric distortion theorem
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SHARP DISTORTION THEOREMS FOR A CLASS OF BIHOLOMORPHIC MAPPINGS IN SEVERAL COMPLEX VARIABLES 被引量:1
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作者 Xiaosong LIU 《Acta Mathematica Scientia》 SCIE CSCD 2022年第2期454-466,共13页
In this paper,we first establish the sharp growth theorem and the distortion theorem of the Frechet derivative for biholomorphic mappings defined on the unit ball of complex Banach spaces and the unit polydisk in C^(n... In this paper,we first establish the sharp growth theorem and the distortion theorem of the Frechet derivative for biholomorphic mappings defined on the unit ball of complex Banach spaces and the unit polydisk in C^(n) with some restricted conditions.We next give the distortion theorem of the Jacobi determinant for biholomorphic mappings defined on the unit ball of C^(n) with an arbitrary norm and the unit polydisk in C^(n) under certain restricted assumptions.Finally we obtain the sharp Goluzin type distortion theorem for biholomorphic mappings defined on the unit ball of complex Banach spaces and the unit polydisk in C^(n) with some additional conditions.The results derived all reduce to the corresponding classical results in one complex variable,and include some known results from the prior literature. 展开更多
关键词 Biholomorphic mapping distortion theorem Frechet derivative Jacobi determinant Goluzin type distortion theorem
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More on Fixed Point Theorem of{a,b,c}-Generalized Nonexpansive Mappings in Normed Spaces 被引量:1
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作者 Sahar Mohamed Ali 《Analysis in Theory and Applications》 2013年第1期1-11,共11页
Let X be a weakly Cauchy normed space in which the parallelogram law holds,C be a bounded closed convex subset of X with one contracting point and T be an{a,b,c}-generalized-nonexpansive mapping from C into C.We prove... Let X be a weakly Cauchy normed space in which the parallelogram law holds,C be a bounded closed convex subset of X with one contracting point and T be an{a,b,c}-generalized-nonexpansive mapping from C into C.We prove that the infimum of the set{‖x-T(x)‖}on C is zero,study some facts concerning the{a,b,c}-generalized-nonexpansive mapping and prove that the asymptotic center of any bounded sequence with respect to C is singleton.Depending on the fact that the{a,b,0}-generalized-nonexpansive mapping from C into C has fixed points,accord-ingly,another version of the Browder's strong convergence theorem for mappings is given. 展开更多
关键词 Fixed point theorem {a b c}-generalized-nonexp ansive mapping asymptotic center Browder's strong convergence theorem.
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