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Convolution Theorem of Fractional Fourier Transformation Derived by Representation Transformation in Quantum Mechancis 被引量:1
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作者 FAN Hong-Yi HAO Ren LU Hai-Liang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第9期611-614,共4页
Based on our previous paper (Commun.Theor.Phys.39 (2003) 417) we derive the convolution theoremof fractional Fourier transformation in the context of quantum mechanics,which seems a convenient and neat way.Generalizat... Based on our previous paper (Commun.Theor.Phys.39 (2003) 417) we derive the convolution theoremof fractional Fourier transformation in the context of quantum mechanics,which seems a convenient and neat way.Generalization of this method to the complex fractional Fourier transformation case is also possible. 展开更多
关键词 分数傅里叶转换 卷积定理 量子力学 转换形式
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A Sound Field Separation and Reconstruction Technique Based on Reciprocity Theorem and Fourier Transform 被引量:1
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作者 李小雷 王宁 +1 位作者 高大治 李琪 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第11期42-45,共4页
We show a method to separate the sound field radiated by a signal source from the sound field radiated by noise sources and to reconstruct the sound field radiated by the signal source. The proposed method is based on... We show a method to separate the sound field radiated by a signal source from the sound field radiated by noise sources and to reconstruct the sound field radiated by the signal source. The proposed method is based on reciprocity theorem and the Fourier transform. Both the sound field and its gradient on a measurement surface are needed in the method. Evanescent waves are considered in the method, which ensures a high resolution reconstruction in the near field region of the signal source when evanescent waves can be measured. A simulation is given to verify the method and the influence of measurement noise on the method is discussed. 展开更多
关键词 A Sound Field Separation and Reconstruction Technique Based on Reciprocity theorem and Fourier transform
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A WIENER-TAUBERIAN THEOREM FOR FOURIER-JACOBI TRANSFORM
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作者 Liu Jianming Zheng Weixing(Nanjing University, China) 《Analysis in Theory and Applications》 1997年第2期97-104,共8页
Let we consider conditions under which the space spanned by generalized translates of f is dense in in terms of Fourier-Jacobi transform of f. This generalizes and improves the earlier results of A. Sitaram on semi-si... Let we consider conditions under which the space spanned by generalized translates of f is dense in in terms of Fourier-Jacobi transform of f. This generalizes and improves the earlier results of A. Sitaram on semi-simple Lie groups of rank one. 展开更多
关键词 exp A WIENER-TAUBERIAN theorem FOR FOURIER-JACOBI transform
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Some minimax theorems with strictly monotone transformation
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作者 TANG Gu-sheng CHENG Cao-zong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2008年第1期69-78,共10页
Some two-function minimax theorems are proved. In these results, the staircase and quantitative-topological conditions of both functions involve strictly monotone transformation and mixing of functional values. Conseq... Some two-function minimax theorems are proved. In these results, the staircase and quantitative-topological conditions of both functions involve strictly monotone transformation and mixing of functional values. Consequently, Lin Quan and Kindler's minimax theorems are generalized. 展开更多
关键词 minimax theorems STAIRCASE monotone transformation.
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Differential Sandwich Theorems for Analytic Functions Defined by an Extended Multiplier Transformation
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作者 Amnah Shammaky 《Advances in Pure Mathematics》 2012年第5期323-329,共7页
In this investigation, we obtain some applications of first order differential subordination and superordination results involving an extended multiplier transformation and other linear operators for certain normalize... In this investigation, we obtain some applications of first order differential subordination and superordination results involving an extended multiplier transformation and other linear operators for certain normalized analytic functions. Some of our results improve previous results. 展开更多
关键词 DIFFERENTIAL SANDWICH theoremS Analytic Functions MULTIPLIER transformATION
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Inversion formula and Parseval theorem for complex continuous wavelet transforms studied by entangled state representation
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作者 胡利云 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第7期263-267,共5页
In a preceding letter (2007 Opt. Lett. 32 554) we propose complex continuous wavelet transforms and found Laguerre-Gaussian mother wavelets family. In this work we present the inversion formula and Parseval theorem ... In a preceding letter (2007 Opt. Lett. 32 554) we propose complex continuous wavelet transforms and found Laguerre-Gaussian mother wavelets family. In this work we present the inversion formula and Parseval theorem for complex continuous wavelet transform by virtue of the entangled state representation, which makes the complex continuous wavelet transform theory complete. A new orthogonal property of mother wavelet in parameter space is revealed. 展开更多
关键词 Parseval theorem complex continuous wavelet transforms entangled state representation
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Helmholtz Theorems, Gauge Transformations, General Covariance and the Empirical Meaning of Gauge Conditions
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作者 Andrew Chubykalo Augusto Espinoza Rolando Alvarado Flores 《Journal of Modern Physics》 2016年第9期1021-1044,共24页
It is well known that the use of Helmholtz decomposition theorem for static vector fields , when applied to the time dependent vector fields , which represent the electromagnetic field, allows us to obtain instan... It is well known that the use of Helmholtz decomposition theorem for static vector fields , when applied to the time dependent vector fields , which represent the electromagnetic field, allows us to obtain instantaneous-like solutions all along . For this reason, some people thought (see e.g. [1] and references therein) that the Helmholtz theorem cannot be applied to time dependent vector fields and some modification is wanted in order to get the retarded solutions. However, the use of the Helmholtz theorem for static vector fields is correct even for time dependent vector fields (see, e.g. [2]), so a relation between the solutions was required, in such a way that a retarded solution can be transformed in an instantaneous one, and conversely. On this paper we want to suggest, following most of the time the mathematical formalism of Woodside in [3], that: 1) there are many Helmholtz decompositions, all equally consistent, 2) each one is naturally related to a space-time structure, 3) when we use the Helmholtz decomposition for the electromagnetic potentials it is equivalent to a gauge transformation, 4) there is a natural methodological criterion for choosing the gauge according to the structure postulated for a global space-time, 5) the Helmholtz decomposition is the manifestation at the level of the fields that a gauge is involved. So, when we relate the retarded solution to the instantaneous one what we do is to change the gauge and the space-time. And, if the Helmholtz decompositions are related to a space-time structure, and are equivalent to gauge transformations, each gauge transformation is natural for a specific space-time. In this way, a Helmholtz decomposition for Euclidean space is equivalent to the Coulomb gauge and a Helmholtz decomposition for the Minkowski space is equivalent to the Lorenz gauge. This leads us to consider that the theories defined by different gauges may be mathematically equivalent, because they can be related by means of a gauge transformation, but they are not empirically equivalent, because they have quite different observational consequences due to the different space-time structure involved. 展开更多
关键词 Helmholtz theorem Gauge transformations Space-Time transformations Symmetries of Differential Equations Underdetermination of Systems of Differential Equations Natural Covariance
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MATLAB在“张量分析”课程教学中的应用 被引量:1
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作者 汪建军 许才军 《科教导刊》 2024年第1期130-132,共3页
张量分析是一种重要的数学工具,它在相对论、电磁场论和连续介质力学等诸多学科都有着广泛的应用。掌握这种数学工具,已成为从事相关科学研究的必备基础。然而,张量分析中非欧几里得空间局部切标架的存在,增加了张量计算和分析的复杂性... 张量分析是一种重要的数学工具,它在相对论、电磁场论和连续介质力学等诸多学科都有着广泛的应用。掌握这种数学工具,已成为从事相关科学研究的必备基础。然而,张量分析中非欧几里得空间局部切标架的存在,增加了张量计算和分析的复杂性。学生在学习“张量分析”课程时面临着抽象概念和复杂公式的理解上的困难。本文提出利用MATLAB工具在绘图、脚本编程和符号推导等方面的强大功能,从旋度分析、坐标变换和定理辅助证明这三个方面,并结合MATLAB脚本代码,展示MATLAB工具辅助于该课程教学的重要作用。教师借助该工具开展课程教学,将帮助学生有效提高对张量分析知识的理解。学生掌握了该课程的基础知识后,便能进一步使用MATLAB的张量工具箱或Pytorch深度学习库进行张量运算操作。 展开更多
关键词 张量分析 坐标变换 定理辅助证明 MATLAB
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线性正则正余弦加权卷积及其应用
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作者 王小霞 冯强 《贵州大学学报(自然科学版)》 2024年第2期15-21,25,共8页
针对积分方程的求解问题,本文提出了利用卷积运算及其卷积定理来讨论两类卷积类积分方程组的解。首先,在线性正则正弦变换与线性正则余弦变换的基础上,定义了线性正则正余弦卷积运算及其加权卷积运算;其次,推导了相应的卷积定理,研究了... 针对积分方程的求解问题,本文提出了利用卷积运算及其卷积定理来讨论两类卷积类积分方程组的解。首先,在线性正则正弦变换与线性正则余弦变换的基础上,定义了线性正则正余弦卷积运算及其加权卷积运算;其次,推导了相应的卷积定理,研究了该卷积与傅里叶正余弦变换卷积运算的关系;最后,讨论了两类卷积类积分方程组的解,给出了该方程解的一般形式。 展开更多
关键词 线性正则正弦变换 线性正则余弦变换 卷积定理 积分方程
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数学哲学与人生智慧
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作者 朱宏伟 《自然杂志》 CAS 2024年第2期157-160,共4页
数学概念深远地影响着人类的思维方式和世界观。文章探讨了贝叶斯定理、泊松分布和傅里叶变换在日常生活中的应用,揭示了这些数学公式背后的深层人生哲理。数学理论不仅能够解释科学现象,也为个人决策提供了可参照的方案,指导我们如何... 数学概念深远地影响着人类的思维方式和世界观。文章探讨了贝叶斯定理、泊松分布和傅里叶变换在日常生活中的应用,揭示了这些数学公式背后的深层人生哲理。数学理论不仅能够解释科学现象,也为个人决策提供了可参照的方案,指导我们如何更新信念、把握机遇,从不同角度理解复杂问题。 展开更多
关键词 贝叶斯定理 泊松分布 傅里叶变换 数学哲学 人工智能
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基于无限长梁模型的车路振动耦合系统半解析解
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作者 赵妍 张步云 +2 位作者 TAN Chin-An 刘志强 胡正林 《汽车工程学报》 2024年第2期217-225,共9页
针对无限长道路与车辆耦合系统响应计算复杂难题,考虑地基的弹性特性与道路不平度,建立基于无限长欧拉-伯努利梁模型的车路振动耦合系统。进而以车辆为参考点建立移动坐标系,提出通过积分变换推导耦合系统振动响应解析解的方法,并应用... 针对无限长道路与车辆耦合系统响应计算复杂难题,考虑地基的弹性特性与道路不平度,建立基于无限长欧拉-伯努利梁模型的车路振动耦合系统。进而以车辆为参考点建立移动坐标系,提出通过积分变换推导耦合系统振动响应解析解的方法,并应用留数定理对其进行数值计算,获得车辆垂向位移、加速度、路面振动响应等系统响应的半解析解。与传统应用模态叠加法的有限长道路与车辆耦合响应相比,具有更高的计算效率与精度,系统参数化研究也证明了该半解析解的有效性。 展开更多
关键词 车路振动耦合 无限长梁模型 积分变换 留数定理 半解析解
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基于Mohand变换求解模糊Volterra积分微分方程
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作者 余乐 陈豫眉 《西安文理学院学报(自然科学版)》 2024年第1期21-26,共6页
Mohand变换是一种常见的积分变换,具有运算时间少的特点.利用模糊Mohand变换求解模糊Volterra积分微分方程,得到方程以参数形式表达的上解和下解.最后通过数值算例验证了模糊Mohand变换求解模糊Volterra积分微分方程的有效性.
关键词 模糊数 模糊Volterra积分微分方程 模糊Mohand变换 卷积定理
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A NOTE ON SINGULAR VALUE DECOMPOSITION FOR RADON TRANSFORM IN R^n 被引量:3
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作者 王金平 杜金元 《Acta Mathematica Scientia》 SCIE CSCD 2002年第3期311-318,共8页
The singular value decomposition is derived when the Radon transform is restricted to functions which are square integrable on the unit ball in R-n with respect to the weight W-lambda(x). It fulfilles mainly by means ... The singular value decomposition is derived when the Radon transform is restricted to functions which are square integrable on the unit ball in R-n with respect to the weight W-lambda(x). It fulfilles mainly by means of the projection-slice theorem. The range of the Radon transform is spanned by products of Gegenbauer polynomials and spherical harmonics. The inverse transform of the those basis functions are given. This immediately leads to an inversion formula by series expansion and range characterizations. 展开更多
关键词 radon transform projection-slice theorem singular value decomposition
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Demonstration of Inverse Scattering Transform for DNLS Equation 被引量:1
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作者 YANG Chun-Nuan YU Jia-Lu WANG Qu-Quan HUANG Nian-Ning 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第2X期299-303,共5页
关键词 逆散射传输 单体解答方法 DNLS解答方法 物理数学
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~ Transform Demonstration of Dark Soliton Solutions Found by Inverse Scattering 被引量:2
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作者 LI Cun YANG Bai-Feng CAI Hao HUANG Nian-Ning 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第2X期244-248,共5页
关键词 逆散射变换 模糊孤立子 LIOUVILLE定理 理论物理
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GALIN’S THEOREM HOLDS FOR MOVING PUNCH 被引量:2
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《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1991年第1期82-87,共6页
This paper presents a formulation for solving three-dimensional moving punch problem. It proves that Galin's theorem holds for the punch. As an example, the study offers some results (including numerical data) of ... This paper presents a formulation for solving three-dimensional moving punch problem. It proves that Galin's theorem holds for the punch. As an example, the study offers some results (including numerical data) of dynamic displacement over an ellipse contact region. 展开更多
关键词 three-dimensional moving contact Lame potentials double Fourier transform influence functions Galin's theorem
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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 THE DECOMPOSITION OF COMPLEX VECTOR SPACES AND THE JORDAN CANONICAL FORM OF COMPLEX LINEAR TRANSFORMATIONS
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作者 肖衡 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1994年第11期997-1003,共7页
New objects characterizing the structure of complex linear transformations areintroduced. These new objects yield a new result for the decomposition of complexvector spaces relative to complex lrnear transformations a... New objects characterizing the structure of complex linear transformations areintroduced. These new objects yield a new result for the decomposition of complexvector spaces relative to complex lrnear transformations and provide all Jordan basesby which the Jordan canonical form is constructed. Accordingly, they can result in thecelebrated Jordan theorem and the third decomposition theorem of space directly. and,moreover, they can give a new deep insight into the exquisite and subtle structure ofthe Jordan form. The latter indicates that the Jordan canonical form of a complexlinear transformation is an invariant structure associated with double arbitrary. choices. 展开更多
关键词 complex vector space complex linear transformation. decompo-sition theorems. Jordan canonical form
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A NEW INTEGRAL TRANSFORM AND ITS APPLICATIONS
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作者 H.M.SRIVASTAVA 罗旻杰 R.K.RAINA 《Acta Mathematica Scientia》 SCIE CSCD 2015年第6期1386-1400,共15页
In the present paper, the authors introduce a new integral transform which yields a number of potentially useful (known or new) integral transfoms as its special cases. Many fundamental results about this new integr... In the present paper, the authors introduce a new integral transform which yields a number of potentially useful (known or new) integral transfoms as its special cases. Many fundamental results about this new integral transform, which are established in this paper, in- clude (for example) existence theorem, Parseval-type relationship and inversion formula. The relationship between the new integral transform with the H-function and the H-transform are characterized by means of some integral identities. The introduced transform is also used to find solution to a certain differential equation. Some illustrative examples are also given. 展开更多
关键词 Laplace transform Sumudu transform natural transform H-FUNCTION H- transform inversion formula Parseval-type relationship existence theorem Borel-Dzrbashjan transform Fubini's theorem Weierstrass's test Heaviside generalized function
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THE SPACES OF CESRO ALMOST CONVERGENT SEQUENCES AND CORE THEOREMS
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作者 Kuddusi Kayaduman Mehmet Sengönül 《Acta Mathematica Scientia》 SCIE CSCD 2012年第6期2265-2278,共14页
As known, the method to obtain a sequence space by using convergence field of an infinite matrix is an old method in the theory of sequence spaces. However, the study of convergence field of an infinite matrix in the ... As known, the method to obtain a sequence space by using convergence field of an infinite matrix is an old method in the theory of sequence spaces. However, the study of convergence field of an infinite matrix in the space of almost convergent sequences is so new (see [15]). The purpose of this paper is to introduce the new spaces ^ ~f and fo consisting of all sequences whose Ceshro transforms of order one are in the spaces f and ^ ~ f0, respectively. Also, in this paper, we show that ^ ~f and ^ ~f0 are linearly isomorphic to the spaces f and f0, respectively. The β- and γ-duals of the spaces ^ ~f and 2% are computed. Furthermore, the classes (^ ~f: μ) and (μ : f) of infinite matrices are characterized for any given sequence space μ, and determined the necessary and sufficient conditions on a matrix A to satisfy Bc-core(Ax) K-core(x), K-core(Ax) Bg-core(x), Bc-core(Ax) Be-core(x), Bc-core(Ax) t-core(x) for all x ∈ t∞. 展开更多
关键词 almost convergence matrix domain of a sequence space β- and γ-duals andmatrix transformations core theorems ISOMORPHISM
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