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Recursion-transform method and potential formulae of the m×n cobweb and fan networks 被引量:12
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作者 谭志中 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第9期82-90,共9页
In this paper, we made a new breakthrough, which proposes a new recursion–transform(RT) method with potential parameters to evaluate the nodal potential in arbitrary resistor networks. For the first time, we found ... In this paper, we made a new breakthrough, which proposes a new recursion–transform(RT) method with potential parameters to evaluate the nodal potential in arbitrary resistor networks. For the first time, we found the exact potential formulae of arbitrary m × n cobweb and fan networks by the RT method, and the potential formulae of infinite and semi-infinite networks are derived. As applications, a series of interesting corollaries of potential formulae are given by using the general formula, the equivalent resistance formula is deduced by using the potential formula, and we find a new trigonometric identity by comparing two equivalence results with different forms. 展开更多
关键词 recursion-transform method network model potential formula exact solution
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MORE ABOUT MELLIN TRANSFORM IN WEAK FUNCTIONS AND MUNTS FORMULA
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作者 丁夏畦 罗佩珠 《Acta Mathematica Scientia》 SCIE CSCD 2004年第1期1-8,共8页
This paper is a further continuation of the paper [1]. In the present paper Mellin transform and Miints formula of weak functions in complex domain will be treated.
关键词 Weak function Mellin transform Miints formula Fourier transform
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Some New Transformation Formulas for q-Series through the Bailey Transform
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作者 Lijun Hao Liangliang Xu 《Advances in Pure Mathematics》 2023年第10期651-661,共11页
In the literature, the Bailey transform has many applications in basic hypergeometric series. In this paper, we derive many new transformation formulas for q-series by means of the Bailey transform. Meanwhile, We also... In the literature, the Bailey transform has many applications in basic hypergeometric series. In this paper, we derive many new transformation formulas for q-series by means of the Bailey transform. Meanwhile, We also obtain some new terminated identities. Furthermore, we establish a companion identity to the Rogers-Ramanujan identity labelled by number (23) on Slater’s list. 展开更多
关键词 Q-SERIES Bailey transform transformation formulas Rogers-Ramanujan Identities
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基于Transformer的深度符号回归方法 被引量:2
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作者 许鹏程 何磊 +2 位作者 李川 钱炜祺 赵暾 《计算机应用》 北大核心 2025年第5期1455-1463,共9页
针对利用遗传进化算法解决符号回归(SR)问题时存在的种群多样性降低以及对超参数敏感等问题,提出基于Transformer的深度符号回归(DSRT)方法。该方法在利用Transformer自回归的方式生成表达式符号序列后,将数据和表达式符号序列的拟合度... 针对利用遗传进化算法解决符号回归(SR)问题时存在的种群多样性降低以及对超参数敏感等问题,提出基于Transformer的深度符号回归(DSRT)方法。该方法在利用Transformer自回归的方式生成表达式符号序列后,将数据和表达式符号序列的拟合度值的变换值当作奖励值,再利用深度强化学习的方法更新模型参数,使模型输出的表达式序列更加拟合数据,并随着模型的不断收敛找出最优的表达式。在SR基准数据集Nguyen上对DSRT方法进行有效性测试,并在200次迭代内将它与DSR(Deep Symbolic Regression)和GP(Genetic Programming)算法进行对比,实验结果验证了DSRT方法的有效性。另外,讨论了各参数对DSRT方法的影响,并在NACA4421数据上进行飞机翼型表面压力系数公式预测实验,将所得到的公式与卡门-钱学森公式作对比,找到了均方根误差(RMSE)较小的数学公式。 展开更多
关键词 符号回归 transformER 深度强化学习 NACA4412 卡门-钱学森公式
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Transformation Formulas for the First Kind of Lauricella’s Function of Several Variables
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作者 Fadhle B. F. Mohsen Ahmed Ali Atash Hussein Saleh Bellehaj 《Journal of Applied Mathematics and Physics》 2016年第6期1112-1119,共8页
Very recently Atash and Al-Gonah [1] derived two extension formulas for Lauricella’s function of the second kind of several variables and . Now in this research paper we derive two families of transformation formulas... Very recently Atash and Al-Gonah [1] derived two extension formulas for Lauricella’s function of the second kind of several variables and . Now in this research paper we derive two families of transformation formulas for the first kind of Lauricella’s function of several variables and with the help of generalized Dixon’s theorem on the sum of the series obtained earlier by Lavoie et al. [2]. Some new and known results are also deduced as applications of our main formulas. 展开更多
关键词 transformation formulas Lauricella’s function Dixon’s Theorem Kampé de Fériet Function
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THE TRANSFORMATION LAW AND TRACE FORMULA ON THETA SERIES UNDER SIEGEL MODULAR GROUP
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作者 周海港 陆洪文 《Acta Mathematica Scientia》 SCIE CSCD 2008年第1期201-209,共9页
The purposes of this article are to discuss the symplectic transformation laws on theta series and to give some explicit formulas for the trace of the symplectic operator.
关键词 theta series symplectic transformation law trace formula
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Concerning Two Formulaic Classes in Computational Combinatorics 被引量:4
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作者 Leetsch C.HSU 《Journal of Mathematical Research with Applications》 CSCD 2012年第2期127-142,共16页
Here introduced and studied are two formulaic classes consisting of various combinatorial algebraic identities and series summation formulas. The basic ideas include utilizing properly the △-operator and Stirling num... Here introduced and studied are two formulaic classes consisting of various combinatorial algebraic identities and series summation formulas. The basic ideas include utilizing properly the △-operator and Stirling numbers for some series transformations. A variety of classic formulas and remarkable identities are shown to be the members of the classes. 展开更多
关键词 difference operator Newton-type series △-operational series transformation summation formula combinatorial identity.
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Reconstruction Results about the Exponential Radon Transform
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作者 JIANG Jun WANG Jinping 《Wuhan University Journal of Natural Sciences》 CAS 2013年第1期25-28,共4页
In this paper, the properties of the exponential Radon transform and its dual are discussed. Furthermore, the analytical reconstruction formulas of exponential Radon transform with two different methods are developed.
关键词 exponential Radon transform dual transform re-construction formula Dirac function
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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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Variation of Constant Formulae for Time Invariant and Time Varying Caputo Fractional Delay Differential Systems 被引量:1
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作者 Hai ZHANG Daiyong WU 《Journal of Mathematical Research with Applications》 CSCD 2014年第5期549-560,共12页
This paper studies the variation of constant formulae for linear Caputo fractional delay differential systems. We discuss the exponential estimates of the solutions for linear time invariant fractional delay different... This paper studies the variation of constant formulae for linear Caputo fractional delay differential systems. We discuss the exponential estimates of the solutions for linear time invariant fractional delay differential systems by using the Gronwall's integral inequality. The variation of constant formula for linear time invariant fractional delay differential systems is obtained by using the Laplace transform method. In terms of the superposition principle of linear systems and fundamental solution matrix, we also establish the variation of constant formula for linear time varying fractional delay differential systems. The obtained results generalize the corresponding ones of integer-order delayed differential equations. 展开更多
关键词 fractional delay differential systems variation formula exponential estimates Laplace transform Gronwall's integral inequality.
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Relativistic Formulae for the Biquaternionic Model of Electro-Gravimagnetic Charges and Currents
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作者 Lyudmila Alexeyeva 《Journal of Modern Physics》 2017年第7期1043-1052,共10页
Here the biquaternionic model of electro-gravimagnetic field (EGM-field) has been considered, which describes the change of EGM-fields, charges and currents in their interaction. The invariance of these equations with... Here the biquaternionic model of electro-gravimagnetic field (EGM-field) has been considered, which describes the change of EGM-fields, charges and currents in their interaction. The invariance of these equations with respect to the group of Poincare-Lorentz transformations has been proved. The relativistic formulae of transformation for density of electric and gravity-magnetic charges and currents, active power and forces have been obtained. 展开更多
关键词 Electro-Gravimagnetic Field Electric CHARGE Gravimagnetic CHARGE Cur-rent Poincare-Lorentz transformation RELATIVISTIC formula
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AN ASYMPTOTIC ORDER OF FOURIER TRANSFORM ON SL(2,R) 被引量:1
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作者 Wang Xinsong and Zheng Weixing (Nanjing University, China) 《Analysis in Theory and Applications》 2003年第1期76-80,共5页
In this paper, a better asymptotic order of Fourier transform on SL(2,R) is obtained by using classical analysis and Lie analysis comparing with that of [5],[6] ,and the Plancherel theorem on C2i(SL(2,R)) is also obta... In this paper, a better asymptotic order of Fourier transform on SL(2,R) is obtained by using classical analysis and Lie analysis comparing with that of [5],[6] ,and the Plancherel theorem on C2i(SL(2,R)) is also obtained as an application. 展开更多
关键词 Fourier transform SL(2 R) Lie algebra Plancherel formula HS-norm
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The New Inversion of Laplace Transform
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作者 Andrey Pavlov V. 《Journal of Mathematics and System Science》 2014年第3期197-201,共5页
The new inversion formula of the Laplace transform is considered. In the formula we use only the positive values ofx SiCoLT(x) = c S(x), L(S(x)) = T(x), c = const., x 〉 O,from the real axis. Si is the sinus... The new inversion formula of the Laplace transform is considered. In the formula we use only the positive values ofx SiCoLT(x) = c S(x), L(S(x)) = T(x), c = const., x 〉 O,from the real axis. Si is the sinus transform, Co is the cosines transform of Fourier and L is the Laplace transform. 展开更多
关键词 Laplace transform new inversion formula of Laplace transform evenness of Laplace transform integral transform ofFourier
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Weinstein Gabor Transform and Applications
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作者 Hatem Mejjaoli Ahmedou Ould Ahmed Salem 《Advances in Pure Mathematics》 2012年第3期203-210,共8页
In this paper we consider Weinstein operator. We define and study the continuous Gabor transform associated with this operator. We prove a Plancherel formula, an inversion formula and a weak uncertainty principle for ... In this paper we consider Weinstein operator. We define and study the continuous Gabor transform associated with this operator. We prove a Plancherel formula, an inversion formula and a weak uncertainty principle for it. As applications, we obtain analogous of Heisenberg’s inequality for the generalized continuous Gabor transform. At the end we give the practical real inversion formula for the generalized continuous Gabor transform. 展开更多
关键词 Weinstein GABOR transform Practical REAL INVERSION formula KERNEL Reproducing Theory
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Immunomodulating Activities of Polysaccharides from ZhuQin Formula and Atractylodes in Hypoimmune Mice 被引量:1
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作者 Min PANG Yichen LUO +3 位作者 Yongfeng HAO Xin YUE Zhaorong ZHU Juan LIU 《Medicinal Plant》 CAS 2018年第1期67-71,共5页
[Objectives] To investigate the infrared identification of ZhuQin Formula and Atractylodes polysaccharides and its effect on immune function in immunocompromised mice. [Methods] In this experiment,the structure of pol... [Objectives] To investigate the infrared identification of ZhuQin Formula and Atractylodes polysaccharides and its effect on immune function in immunocompromised mice. [Methods] In this experiment,the structure of polysaccharides was analyzed by Fourier transform infrared spectroscopy. The experiment was divided into the polysaccharide groups of high,medium and low dose of ZhuQin,the extraction group of ZhuQin,the polysaccharide group of Atractylodes,the positive drug group,the blank group and the model group. The model of immunosuppressed mice was established by intraperitoneal injection of cyclophosphamide. The carbon clearance index,immune organ index,serum hemolysin,spleen T and B lymphocyte transformation rate were determined. [Results]The results show that the polysaccharides have obvious absorption peaks of polysaccharides; Formula extracts and polysaccharides can enhance the immune function of immunosuppressive mice at a certain dose level,and the effect of formula polysaccharide is better than that of extract and single traditional Chinese medicine polysaccharides. [Conclusions] The results suggest that the polysaccharides of ZhuQin Formula and Atractylodes may be acidic polysaccharides containing pyran ring and furan ring. ZhuQin Formula polysaccharide may play an immunomodulatory role mainly by improving the specific immunity of the organism. 展开更多
关键词 ZhuQin formula polysaccharide Atractylodes polysaccharide Fourier transform infrared spectroscopy Immune function
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Behavior of a Scale Factor for Wiener Integrals and a Fourier Stieltjes Transform on the Wiener Space
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作者 Young Sik Kim 《Applied Mathematics》 2018年第5期488-495,共8页
The purpose of this paper is to investigate the behavior of a Wiener integral along the curve C of the scale factor ρ > 0 for the Wiener integral ∫C0[0,T]F(ρx)dm(x) about the function defined on the Wiener space... The purpose of this paper is to investigate the behavior of a Wiener integral along the curve C of the scale factor ρ > 0 for the Wiener integral ∫C0[0,T]F(ρx)dm(x) about the function defined on the Wiener space C0[0,T], where θ(t,u) is a Fourier-Stieltjes transform of a complex Borel measure. 展开更多
关键词 WIENER Space WIENER INTEGRAL FEYNMAN INTEGRAL ANALYTIC WIENER INTEGRAL ANALYTIC FEYNMAN INTEGRAL Fourier-Stieltjes transform Change of SCALE formula SCALE Factor
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Green Function of Generalized Time Fractional Diffusion Equation Using Addition Formula of Mittag-Leffler Function
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作者 Fang Wang Jinmeng Zhang 《Journal of Applied Mathematics and Physics》 2022年第9期2720-2732,共13页
In this paper, we use the Mittag-Leffler addition formula to solve the Green function of generalized time fractional diffusion equation in the whole plane and prove the convergence of the Green function.
关键词 Mittag-Leffler Function Mellin transforms Generalized Time Fractional Diffusion Equation Green Function Addition formula
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CONVERSION FORMULAS FOR RATIONAL BEZIER SURFACES
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作者 Hu Shimin Wang Guozhao 《Computer Aided Drafting,Design and Manufacturing》 1996年第1期18-24,共2页
In this paper, we investigate the inherent relationship between two types of rational Bezier surfaces. We present a conversion formula for rational Bezier surfaces from triangular patches to rectangular patches with s... In this paper, we investigate the inherent relationship between two types of rational Bezier surfaces. We present a conversion formula for rational Bezier surfaces from triangular patches to rectangular patches with straight forward geometric interpretations, an inverse process of such conversion is also considered. 展开更多
关键词 ss: rational Bezier patch degree elevation conversion formula parameter transformation
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基于Copula理论及等概率分段的有源配电网概率潮流计算
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作者 贾玉栋 刘文彬 +3 位作者 穆希桢 慕小斌 朱永强 夏瑞华 《电测与仪表》 北大核心 2025年第7期49-57,共9页
针对有源配电网中源荷双侧强不确定性场景,文中提出一种基于Copula理论及等概率分段的有源配电网概率潮流计算方法。通过Copula函数和Rosenblatt逆变换实现输入随机变量相关性的描述和独立性的转换。为使基于Copula理论的相关性分析易... 针对有源配电网中源荷双侧强不确定性场景,文中提出一种基于Copula理论及等概率分段的有源配电网概率潮流计算方法。通过Copula函数和Rosenblatt逆变换实现输入随机变量相关性的描述和独立性的转换。为使基于Copula理论的相关性分析易于进行,不再将机组出力离散化,而是将机组出力概率模型在其出力区间进行分段化处理,求取分段区间下的条件概率密度函数。提出基于等概率原则的区间分段方法进行区间分段,通过全概率公式,将完整概率潮流计算分解成多个高精度的条件概率潮流计算,采用Gram-Charlier(GC)级数实现概率分布函数的拟合。 展开更多
关键词 新能源 概率潮流 COPULA理论 Rosenblatt变换 全概率公式
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考虑直流偏磁和非正弦激励影响的高频变压器磁芯损耗修正模型
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作者 张献 陈方宇 +3 位作者 宋文乐 王磊 刘成宇 代中余 《电机与控制学报》 北大核心 2025年第7期85-95,共11页
高频变压器磁芯损耗的精确计算,对电力电子器件的优化设计具有重要意义。首先,针对经典损耗分离方程在非正弦电压激励下磁芯损耗计算精度较低的问题,选取梯形波和方波作为非正弦激励,通过法拉第电磁感应定律得到带有波形因数的磁通密度... 高频变压器磁芯损耗的精确计算,对电力电子器件的优化设计具有重要意义。首先,针对经典损耗分离方程在非正弦电压激励下磁芯损耗计算精度较低的问题,选取梯形波和方波作为非正弦激励,通过法拉第电磁感应定律得到带有波形因数的磁通密度分段曲线,分别修正高频变压器磁芯涡流损耗和剩余损耗解析式。其次,考虑到高频变压器在实际工作状态下可能存在一定程度的直流偏磁,探究直流偏磁分量和磁通密度对磁滞损耗的非线性耦合关系,基于直流偏磁分量修正磁滞损耗解析式,推导出综合考虑直流偏磁和非正弦激励的高频变压器磁芯改进损耗分离模型。最后,搭建磁芯损耗测量平台,通过实验数据得出修正模型拟合参数,将经典模型和修正模型分别与实测值作误差分析,验证本文提出的磁芯损耗修正模型的准确性和有效性。 展开更多
关键词 高频变压器 非正弦激励 波形因数 磁芯损耗 损耗分离公式 直流偏磁
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