期刊文献+
共找到987篇文章
< 1 2 50 >
每页显示 20 50 100
THE JACKSON THEOREM IN B_a SPACES 被引量:3
1
作者 Wu Garidi (Inner Mongolia Normal University,China) 《Analysis in Theory and Applications》 1996年第2期60-69,共10页
As everyone knows,the classical Jackson theorem in approximation theory was generalized in Lp spaces by R.A.Devore.In this paper,we proved the Jackson theorem in B,spaces which introduced by Ding Xia Xi,
关键词 THE jackson theorem IN B_a sPACEs APPI
下载PDF
New Asymptotic Results on Fermat-Wiles Theorem
2
作者 Kimou Kouadio Prosper Kouakou Kouassi Vincent Tanoé François 《Advances in Pure Mathematics》 2024年第6期421-441,共21页
We analyse the Diophantine equation of Fermat xp yp = zp with p > 2 a prime, x, y, z positive nonzero integers. We consider the hypothetical solution (a, b, c) of previous equation. We use Fermat main divisors, Dio... We analyse the Diophantine equation of Fermat xp yp = zp with p > 2 a prime, x, y, z positive nonzero integers. We consider the hypothetical solution (a, b, c) of previous equation. We use Fermat main divisors, Diophantine remainders of (a, b, c), an asymptotic approach based on Balzano Weierstrass Analysis Theorem as tools. We construct convergent infinite sequences and establish asymptotic results including the following surprising one. If z y = 1 then there exists a tight bound N such that, for all prime exponents p > N , we have xp yp zp. 展开更多
关键词 Fermat’s Last theorem Fermat-Wiles theorem Kimou’s Divisors Diophantine Quotient Diophantine Remainders Balzano Weierstrass Analysis theorem
下载PDF
Small Modular Solutions to Fermat’s Last Theorem
3
作者 Thomas Beatty 《Advances in Pure Mathematics》 2024年第10期797-805,共9页
The proof by Andrew Wiles of Fermat’s Last Theorem in 1995 resolved the existence question for non-trivial solutions in integers x,y,zto the equation xn+yn=znfor n>2. There are none. Surprisingly, there are infini... The proof by Andrew Wiles of Fermat’s Last Theorem in 1995 resolved the existence question for non-trivial solutions in integers x,y,zto the equation xn+yn=znfor n>2. There are none. Surprisingly, there are infinitely many solutions if the problem is recast in terms of modular arithmetic. Over a hundred years ago Issai Schur was able to show that for any n there is always a sufficiently large prime p0such that for all primes p≥p0the congruence xn+yn≡zn(modp)has a non-trivial solution. Schur’s argument wasnon-constructive, and there is no systematic method available at present to construct specific examples for small primes. We offer a simple method for constructing all possible solutions to a large class of congruences of this type. 展开更多
关键词 Fermat’s Last theorem Modular Arithmetic CONGRUENCEs Prime Numbers Primitive Roots Indices Ramsey Theory schur’s Lemma in Ramsey Theory
下载PDF
Whole Perfect Vectors and Fermat’s Last Theorem
4
作者 Ramon Carbó-Dorca 《Journal of Applied Mathematics and Physics》 2024年第1期34-42,共9页
A naïve discussion of Fermat’s last theorem conundrum is described. The present theorem’s proof is grounded on the well-known properties of sums of powers of the sine and cosine functions, the Minkowski norm de... A naïve discussion of Fermat’s last theorem conundrum is described. The present theorem’s proof is grounded on the well-known properties of sums of powers of the sine and cosine functions, the Minkowski norm definition, and some vector-specific structures. 展开更多
关键词 Fermat’s Last theorem Whole Perfect Vectors sine and Cosine Functions Natural and Rational Vectors Fermat Vectors
下载PDF
Hardy型A_μ空间中的Jackson定理 被引量:4
5
作者 陈英伟 王志军 刘玉军 《河北师范大学学报(自然科学版)》 CAS 北大核心 2013年第2期113-118,共6页
在Cn中的星形圆型上对Hardy型Aμ函数空间中的全纯函数构造逼近多项式,得出逼近的正定理即Jackson定理.作为Aμ空间的具体例子,给出了Fock空间Apm上的Jackson定理.
关键词 Aμ空间 多项式逼近 jackson定理 HARDY空间 FOCK空间
下载PDF
有界对称域上Ω代数中的Jackson定理 被引量:2
6
作者 王志军 陈英伟 《河北大学学报(自然科学版)》 CAS 北大核心 2014年第4期342-346,共5页
对多复变Cn中有界对称域Ω上球代数的中心逼近性质进行了研究.通过建立多项式偏差估计,最终获得了Jackson型定理.
关键词 Ω代数 jackson定理 光滑模 有界对称域
下载PDF
Müntz有理逼近的点态Jackson型估计 被引量:6
7
作者 王建力 《数学杂志》 CSCD 北大核心 2004年第4期403-405,共3页
Müntz系统的非线性使得其逼近速度刻画成为一个困难的问题 .本文考虑条件λn+ 1 -λn ≥Mn2 下 ,Müntz系统 {xλn}有理逼近的一个点态Jackson型估计 ,这是对J.
关键词 Muentz有理函数 点态逼近 jackson型估计
下载PDF
四元数Hardy空间中的slice正则Jackson定理 被引量:1
8
作者 陈英伟 王志军 《河北大学学报(自然科学版)》 CAS 北大核心 2019年第3期230-234,共5页
对于非交换领域四元数上2种类型的Hardy空间,构造了新的de la Vallée Poussin卷积算子,进而得到了高阶光滑模的slice正则Jackson逼近定理.
关键词 四元数Hardy空间 jackson定理 de la Vallée Poussin算子 正则多项式
下载PDF
球面带形平移网络逼近的Jackson定理 被引量:4
9
作者 盛宝怀 《数学进展》 CSCD 北大核心 2006年第3期325-335,共11页
研究了球面带型平移网络逼近阶用球面调和多项式的最佳逼近及光滑模的刻画问题.借助于球调和多项式的最佳逼近多项式和Riesz平均构造出了单位球面Sq上的带形平移网络,并建立了球面带形平移网络对Lp(Sq)中函数一致逼近的Jackson型定理... 研究了球面带型平移网络逼近阶用球面调和多项式的最佳逼近及光滑模的刻画问题.借助于球调和多项式的最佳逼近多项式和Riesz平均构造出了单位球面Sq上的带形平移网络,并建立了球面带形平移网络对Lp(Sq)中函数一致逼近的Jackson型定理.所得结果表明球面带形平移网络可以达到球调和多项式的逼近阶. 展开更多
关键词 球调和多项式 平移网络 RIEsZ平均 逼近 jackson定理
下载PDF
L_2中的Jackson不等式与函数类的Kolmogorov n-宽度 被引量:1
10
作者 耿爱成 王树新 《辽宁师范大学学报(自然科学版)》 CAS 2012年第3期300-304,共5页
研究了L2空间中用三角多项式逼近周期可微函数时关于S-平均连续模的Jackson不等式,得到了Jackson不等式中最小常数的精确值.涉及的函数类Fα,rh,φ由L2r中满足约束条件ωα,S(f(r);h)≤φ(h)的函数f组成,其中α≥1/2,r∈■,0<h≤π/(... 研究了L2空间中用三角多项式逼近周期可微函数时关于S-平均连续模的Jackson不等式,得到了Jackson不等式中最小常数的精确值.涉及的函数类Fα,rh,φ由L2r中满足约束条件ωα,S(f(r);h)≤φ(h)的函数f组成,其中α≥1/2,r∈■,0<h≤π/(2n),φ(t)为[0,+∞)上的连续增函数且φ(0)=0.并计算了F(α,r)(h,φ)在L2中的Kolmogorov n-宽度的精确值,同时得到F(h,φ)(α,r)中函数f的Fourier系数绝对值的上确界的精确值.其中L2=L2[0,2π]表示以2π为周期的勒贝格平方可积实函数空间,Lr2表示由L2中r-1阶导数f(r-1)绝对连续,r阶导数f(r)∈L2的函数f组成的集合. 展开更多
关键词 steklov函数 s-平均连续模 jackson不等式 Kolmogorovn-宽度
下载PDF
Q_p空间中向量型Jackson定理
11
作者 陈英伟 王志军 王占京 《河北师范大学学报(自然科学版)》 CAS 2015年第4期277-282,共6页
Jackson定理是函数逼近的中心正定理.首先引入单位多圆柱Un上的Qp空间,其为单位圆盘U上Qp空间在多圆柱Un上的拓展.再利用高阶光滑模得到了Qp空间上的向量型Jackson逼近不等式:Ek(f,Qp)≤Cωr(1/k,f,Qp),其中Ek(f,Qp)为f∈Qp的向量阶多... Jackson定理是函数逼近的中心正定理.首先引入单位多圆柱Un上的Qp空间,其为单位圆盘U上Qp空间在多圆柱Un上的拓展.再利用高阶光滑模得到了Qp空间上的向量型Jackson逼近不等式:Ek(f,Qp)≤Cωr(1/k,f,Qp),其中Ek(f,Qp)为f∈Qp的向量阶多项式最佳逼近,ωr(1/k,f,Qp)为相应的向量阶光滑模. 展开更多
关键词 QP空间 jackson定理 向量型光滑模 多圆柱
下载PDF
若干函数空间中Jackson定理及有关问题
12
作者 陈广荣 赵天宇 《宝鸡文理学院学报(自然科学版)》 CAS 1997年第4期14-18,共5页
研究了Lp空间、LM&空间、Ba空间中函数及各阶导函数用多项式算子同时逼近的Jackson定量的证明过程和使用的方法,阐述了这些函数空间相互联系与不同之处。
关键词 函数空间 jackson定理 逼近 K泛函
下载PDF
层次化的K.Fan’s Theorem
13
作者 朱凤梅 李令强 孟广武 《聊城大学学报(自然科学版)》 2010年第2期1-3,89,共4页
在L-拓扑空间中,对任意LF集,我们利用层次化的K.Fan’s Theorem定义了一种层次连通并研究了其基本性质.
关键词 L-拓扑空间 层次连通 K.Fan’s theorem
下载PDF
基于S-R和分解定理的二维几何非线性问题的虚单元法求解
14
作者 江巍 尹豪 +3 位作者 吴剑 汤艳春 李坤鹏 郑宏 《工程力学》 EI CSCD 北大核心 2024年第8期23-35,共13页
应变-旋转(Strain-Rotation,S-R)和分解定理为分析几何非线性问题提供了合理可靠的理论基础,但用有限元求解时会遇到大变形发生后的网格畸变问题。近年提出的虚单元法(Virtual element method,VEM)适用于一般的多边形网格,因此,该文尝... 应变-旋转(Strain-Rotation,S-R)和分解定理为分析几何非线性问题提供了合理可靠的理论基础,但用有限元求解时会遇到大变形发生后的网格畸变问题。近年提出的虚单元法(Virtual element method,VEM)适用于一般的多边形网格,因此,该文尝试使用一阶虚单元求解基于S-R和分解定理的二维几何非线性问题,以克服网格畸变的影响。基于重新定义的多项式位移空间基函数,推演获得一阶虚单元分析线弹性力学问题时允许位移空间向多项式位移空间的投影表达式;按照虚单元法双线性格式的计算规则,分析处理基于更新拖带坐标法和势能率原理的增量变分方程;进而建立离散系统方程及其矩阵表达形式,并编制MATLAB求解程序;采用常规多边形网格和畸变网格,应用该文算法分析均布荷载下的悬臂梁和均匀内压下的厚壁圆筒变形。结果与已有文献和ANSYS软件的对比表明:该文算法在两种网格中均可有效执行且具备足够数值精度。总体该文算法为基于S-R和分解定理的二维几何非线性问题求解提供了一种鲁棒方法。 展开更多
关键词 s-R和分解定理 虚单元法 几何非线性 网格畸变 多边形网格
下载PDF
VECTORIAL EKELAND'S VARIATIONAL PRINCIPLE WITH A W-DISTANCE AND ITS EQUIVALENT THEOREMS 被引量:8
15
作者 丘京辉 李博 贺飞 《Acta Mathematica Scientia》 SCIE CSCD 2012年第6期2221-2236,共16页
By using the properties of w-distances and Gerstewitz's functions, we first give a vectorial Takahashi's nonconvex minimization theorem with a w-distance. From this, we deduce a general vectorial Ekeland's variatio... By using the properties of w-distances and Gerstewitz's functions, we first give a vectorial Takahashi's nonconvex minimization theorem with a w-distance. From this, we deduce a general vectorial Ekeland's variational principle, where the objective function is from a complete metric space into a pre-ordered topological vector space and the perturbation contains a w-distance and a non-decreasing function of the objective function value. From the general vectorial variational principle, we deduce a vectorial Caristfs fixed point theorem with a w-distance. Finally we show that the above three theorems are equivalent to each other. The related known results are generalized and improved. In particular, some conditions in the theorems of [Y. Araya, Ekeland's variational principle and its equivalent theorems in vector optimization, J. Math. Anal. Appl. 346(2008), 9-16] are weakened or even completely relieved. 展开更多
关键词 Takahashi's minimization theorem Ekeland's variational principle Caristi'sfixed point theorem Gerstewitz's function w-distance
下载PDF
Noether's theorems of a fractional Birkhoffian system within Riemann-Liouville derivatives 被引量:17
16
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
下载PDF
SOME NEW EXTENSIONS OF EDELSTEIN-SUZUKI-TYPE FIXED POINT THEOREM TO G-METRIC AND G-CONE METRIC SPACES 被引量:3
17
作者 Fridoun MORADLOU Peyman SALIMI Pasquale VETRO 《Acta Mathematica Scientia》 SCIE CSCD 2013年第4期1049-1058,共10页
In this paper, we prove some fixed point theorems for generalized contractions in the setting of G-metric spaces. Our results extend a result of Edelstein [M. Edelstein, On fixed and periodic points under contractive ... In this paper, we prove some fixed point theorems for generalized contractions in the setting of G-metric spaces. Our results extend a result of Edelstein [M. Edelstein, On fixed and periodic points under contractive mappings, J. London Math. Soc., 37 (1962), 74-79] and a result of Suzuki [T. Suzuki, A new type of fixed point theorem in metric spaces, Nonlinear Anal., 71 (2009), 5313-5317]. We prove, also, a fixed point theorem in the setting of G-cone metric spaces. 展开更多
关键词 G-metric spaces G-cone metric spaces fixed point Edelstein's theorem suzuki's theorem
下载PDF
Mei’s symmetry theorem for time scales nonshifted mechanical systems 被引量:7
18
作者 Yi Zhang 《Theoretical & Applied Mechanics Letters》 CSCD 2021年第5期246-251,共6页
We focus on Mei symmetry for time scales nonshifted mechanical systems within Lagrangian framework and its resulting new conserved quantities.Firstly,the dynamic equations of time scales nonshifted holonomic systems a... We focus on Mei symmetry for time scales nonshifted mechanical systems within Lagrangian framework and its resulting new conserved quantities.Firstly,the dynamic equations of time scales nonshifted holonomic systems and time scales nonshifted nonholonomic systems are derived from the generalized Hamilton’s principle.Secondly,the definitions of Mei symmetry on time scales are given and its criterions are deduced.Finally,Mei’s symmetry theorems for time scales nonshifted holonomic conservative systems,time scales nonshifted holonomic nonconservative systems and time scales nonshifted nonholonomic systems are established and proved,and new conserved quantities of above systems are obtained.Results are illustrated with two examples. 展开更多
关键词 Mei’s symmetry theorem Nonholonomic system Nonconservative system Time scales Nonshifted calculus of variation
下载PDF
ON THE CONDITIONAL VERSION OFKOLMOGOROV'S THREE-SERIES THEOREM 被引量:1
19
作者 刘国欣 《Acta Mathematica Scientia》 SCIE CSCD 1999年第3期300-306,共7页
This paper studies the conditional version of Kolmogorov’s three-series theorem, and gets a new extention form of the conditional version. The results here present us an answer to the question when (or where) the con... This paper studies the conditional version of Kolmogorov’s three-series theorem, and gets a new extention form of the conditional version. The results here present us an answer to the question when (or where) the conditional version also provide necessary conditions for convergence in dependent cases. Furthermore, some new sufficient conditions are obtained. 展开更多
关键词 Three-series theorem dependent r.v. s predictable local absolute CONTINUITY MARTINGALE
下载PDF
THE PICARD THEOREM ON S-METRIC SPACES 被引量:1
20
作者 Nihal Yihnaz OZGUR Nihal TAS 《Acta Mathematica Scientia》 SCIE CSCD 2018年第4期1245-1258,共14页
Recently, the notion of an S-metric space is defined and extensively studied as a generalization of a metric space. In this paper, we define the notion of the S∞-space and prove its completeness. We obtain a new gene... Recently, the notion of an S-metric space is defined and extensively studied as a generalization of a metric space. In this paper, we define the notion of the S∞-space and prove its completeness. We obtain a new generalization of the classical "Picard Theorem". 展开更多
关键词 s∞-space COMPLETENEss Picard theorem initial value problem
下载PDF
上一页 1 2 50 下一页 到第
使用帮助 返回顶部