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Results Involving Partial Differential Equations and Their Solution by Certain Integral Transform
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作者 Rania Saadah Mohammed Amleh +2 位作者 Ahmad Qazza Shrideh Al-Omari Ahmet Ocak Akdemir 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1593-1616,共24页
In this study,we aimto investigate certain triple integral transformand its application to a class of partial differentialequations.We discuss various properties of the new transformincluding inversion, linearity, exi... In this study,we aimto investigate certain triple integral transformand its application to a class of partial differentialequations.We discuss various properties of the new transformincluding inversion, linearity, existence, scaling andshifting, etc. Then,we derive several results enfolding partial derivatives and establish amulti-convolution theorem.Further, we apply the aforementioned transform to some classical functions and many types of partial differentialequations involving heat equations,wave equations, Laplace equations, and Poisson equations aswell.Moreover,wedraw some figures to illustrate 3-D contour plots for exact solutions of some selected examples involving differentvalues in their variables. 展开更多
关键词 ARA transform double ARA transform triple ARA transform partial differential equations integral transform
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Major-Countries Competition and Pivot to the Asia-Pacific:the Strategic Transformation and Influence of“Global NATO”
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作者 Jin Ling 《Contemporary World》 2024年第4期30-33,共4页
As a product of the Cold War,NATO did not disintegrate with the end of it,but rather,it has sought to become“global NATO”through continuous expansion and transformation,in order to hold wider sway in international s... As a product of the Cold War,NATO did not disintegrate with the end of it,but rather,it has sought to become“global NATO”through continuous expansion and transformation,in order to hold wider sway in international security.In its 75-year history,NATO has made numerous moves including adopting confrontational security thinking,building exclusive alliances,conducting humanitarian intervention and crisis management,expanding eastward and northward and involving in the Asia-Pacific. 展开更多
关键词 NATO transformation integrATE
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THE INTEGRAL TYPE GAUGE TRANSFORMATION AND THE ADDITIONAL SYMMETRY FOR THE CONSTRAINED KP HIERARCHY 被引量:2
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作者 程纪鹏 贺劲松 《Acta Mathematica Scientia》 SCIE CSCD 2015年第5期1111-1121,共11页
In this paper, the compatibility between the integral type gauge transformation and the additional symmetry of the constrained KP hierarchy is given. And the string-equation constraint in matrix models is also derived.
关键词 constrained KP hierarchy integral type gauge transformation additional symmetry.
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MATHEMATICAL PROBLEMS IN THE INTEGRAL-TRANSFORMATION METHOD OF DYNAMIC CRACK
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作者 边文凤 王彪 贾宝贤 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2004年第3期252-256,共5页
In the investigation on fracture mechanics,the potential function was introduced, and the moving differential equation was constructed. By making Laplace and Fourier transformation as well as sine and cosine transform... In the investigation on fracture mechanics,the potential function was introduced, and the moving differential equation was constructed. By making Laplace and Fourier transformation as well as sine and cosine transformation to moving differential equations and various responses, the dual equation which is constructed from boundary conditions lastly was solved. This method of investigating dynamic crack has become a more systematic one that is used widely. Some problems are encountered when the dynamic crack is studied. After the large investigation on the problems, it is discovered that during the process of mathematic derivation, the method is short of precision, and the derived results in this method are accidental and have no credibility.A model for example is taken to explain the problems existing in initial deriving process of the integral_transformation method of dynamic crack. 展开更多
关键词 potential function integral transform dynamic crack dual equation
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FOURIER TRANSFORMATION AND SINGULAR INTEGRALS ON SELF-SIMILAR MEASURE
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作者 Wu Baoyi Su Weiyi, Nanjing University, China Department of Mathematics Nanjing University Nanjing 210093 PRC 《Analysis in Theory and Applications》 1998年第4期102-114,共13页
This paper serves two purposes. One is to modify Strichartz's results with respect to the asymptotic averages of the Fourier transform of μ on , self-similar measure defined by Hutchinson. Another purpose is to c... This paper serves two purposes. One is to modify Strichartz's results with respect to the asymptotic averages of the Fourier transform of μ on , self-similar measure defined by Hutchinson. Another purpose is to consider a singular integral operator on μ and show that this op- erator is of type (p,p)(1<p<∞). 展开更多
关键词 SHOW FOURIER transformation AND SINGULAR integralS ON SELF-SIMILAR MEASURE MATH APPI
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On How to Achieve the Scientific Transformation From College Integral English to Academic English
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作者 LIU Xu-liang 《Sino-US English Teaching》 2013年第7期543-547,共5页
In order to meet the trend of China's rapid economic and social development and the internationalization of higher education, a new round of college English teaching reform is ready to start. Following the pilot refo... In order to meet the trend of China's rapid economic and social development and the internationalization of higher education, a new round of college English teaching reform is ready to start. Following the pilot reform by colleges and universities in Beijing, some colleges and universities in Shanghai will also initiate college English teaching reform program this fall. According to SCETFR (Shanghai College English Teaching Frame of Reference), the core of the new round of reform is to replace the traditional integral or comprehensive English with academic English, and through which to strive to improve students' English language ability in academic study and profession, and help them build a strong competence in international exchanges and competitions. The author, based on the status quo of China's current college English teaching, made some forward-looking predictions to the reform, and put forward some constructive proposals and measures 展开更多
关键词 college English teaching reform integral English academic English scientific transformation
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Dynamic response of axially moving Timoshenko beams: integral transform solution 被引量:5
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作者 安晨 苏健 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2014年第11期1421-1436,共16页
The generalized integral transform technique (GITT) is used to find a semianalytical numerical solution for dynamic response of an axially moving Timoshenko beam with clamped-clamped and simply-supported boundary co... The generalized integral transform technique (GITT) is used to find a semianalytical numerical solution for dynamic response of an axially moving Timoshenko beam with clamped-clamped and simply-supported boundary conditions, respectively. The implementation of GITT approach for analyzing the forced vibration equation eliminates the space variable and leads to systems of second-order ordinary differential equations (ODEs) in time. The MATHEMATICA built-in function, NDSolve, is used to numerically solve the resulting transformed ODE system. The good convergence behavior of the suggested eigenfunction expansions is demonstrated for calculating the transverse deflection and the angle of rotation of the beam cross-section. Moreover, parametric studies are performed to analyze the effects of the axially moving speed, the axial tension, and the amplitude of external distributed force on the vibration amplitude of axially moving Timoshenko beams. 展开更多
关键词 axially moving Timoshenko beam transverse vibration integral transform hybrid solution
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Analytical solution for stress and deformation of the mining floor based on integral transform 被引量:5
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作者 Feng Qiang Jiang Binsong 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2015年第4期581-586,共6页
Following exploitation of a coal seam, the final stress field is the sum of in situ stress field and an excavation stress field. Based on this feature, we firstly established a mechanics analytical model of the mining... Following exploitation of a coal seam, the final stress field is the sum of in situ stress field and an excavation stress field. Based on this feature, we firstly established a mechanics analytical model of the mining floor strata. Then the study applied Fourier integral transform to solve a biharmonic equation,obtaining the analytical solution of the stress and displacement of the mining floor. Additionally, this investigation used the Mohr–Coulomb yield criterion to determine the plastic failure depth of the floor strata. The calculation process showed that the plastic failure depth of the floor and floor heave are related to the mining width, burial depth and physical–mechanical properties. The results from an example show that the curve of the plastic failure depth of the mining floor is characterized by a funnel shape and the maximum failure depth generates in the middle of mining floor; and that the maximum and minimum principal stresses change distinctly in the shallow layer and tend to a fixed value with an increase in depth. Based on the displacement results, the maximum floor heave appears in the middle of the stope and its value is 0.107 m. This will provide a basis for floor control. Lastly, we have verified the analytical results using FLAC3 Dto simulate floor excavation and find that there is some deviation between the two results, but their overall tendency is consistent which illustrates that the analysis method can well solve the stress and displacement of the floor. 展开更多
关键词 integral transform Mining floor Plastic failure depth Floor heave Analytical solution
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A complementary integrated Transformer network for hyperspectral image classification
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作者 Diling Liao Cuiping Shi Liguo Wang 《CAAI Transactions on Intelligence Technology》 SCIE EI 2023年第4期1288-1307,共20页
In the past,convolutional neural network(CNN)has become one of the most popular deep learning frameworks,and has been widely used in Hyperspectral image classification tasks.Convolution(Conv)in CNN uses filter weights... In the past,convolutional neural network(CNN)has become one of the most popular deep learning frameworks,and has been widely used in Hyperspectral image classification tasks.Convolution(Conv)in CNN uses filter weights to extract features in local receiving domain,and the weight parameters are shared globally,which more focus on the highfrequency information of the image.Different from Conv,Transformer can obtain the long‐term dependence between long‐distance features through modelling,and adaptively focus on different regions.In addition,Transformer is considered as a low‐pass filter,which more focuses on the low‐frequency information of the image.Considering the complementary characteristics of Conv and Transformer,the two modes can be integrated for full feature extraction.In addition,the most important image features correspond to the discrimination region,while the secondary image features represent important but easily ignored regions,which are also conducive to the classification of HSIs.In this study,a complementary integrated Transformer network(CITNet)for hyperspectral image classification is proposed.Firstly,three‐dimensional convolution(Conv3D)and two‐dimensional convolution(Conv2D)are utilised to extract the shallow semantic information of the image.In order to enhance the secondary features,a channel Gaussian modulation attention module is proposed,which is embedded between Conv3D and Conv2D.This module can not only enhance secondary features,but suppress the most important and least important features.Then,considering the different and complementary characteristics of Conv and Transformer,a complementary integrated Transformer module is designed.Finally,through a large number of experiments,this study evaluates the classification performance of CITNet and several state‐of‐the‐art networks on five common datasets.The experimental results show that compared with these classification networks,CITNet can provide better classification performance. 展开更多
关键词 complementary integrated transformer module convolutional neural network Gaussian modulation transformER
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A New Kind of Two-Fold Integration Transformation in Phase Space and Its Uses in Weyl Ordering of Operators 被引量:3
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作者 FAN Hong-Yi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第10期935-937,共3页
We propose a new two-fold integration transformation in p-q phase space∫∫^∞-∞dpdq/π e^2i(p-x)(q-y)f(p,q)≡G(x,y),which possesses some well-behaved transformation properties. We apply this transformation t... We propose a new two-fold integration transformation in p-q phase space∫∫^∞-∞dpdq/π e^2i(p-x)(q-y)f(p,q)≡G(x,y),which possesses some well-behaved transformation properties. We apply this transformation to the Weyl ordering of operators, especially those Q-P ordered and P-Q ordered operators. 展开更多
关键词 new two-fold integration transform phase space Weyl ordering of operators
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New two-fold integration transformation for the Wigner operator in phase space quantum mechanics and its relation to operator ordering 被引量:2
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作者 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第4期42-49,共8页
Using the Weyl ordering of operators expansion formula (Hong-Yi Fan, J. Phys.A 25 (1992) 3443) this paper finds a kind of two-fold integration transformation about the Wigner operator △( q',p) q-number transf... Using the Weyl ordering of operators expansion formula (Hong-Yi Fan, J. Phys.A 25 (1992) 3443) this paper finds a kind of two-fold integration transformation about the Wigner operator △( q',p) q-number transform) in phase space quantum mechanics,∫∫∞-∞dp'dq'/π △(q',p')e-2i( p-p')( q-q')=δ( p-P)δ( q-Q),∫∫∞-∞dqdpδ(p-P)δ(q-Q)e2i(p-p')(q-q')=△(q',p'),whereQ,P are the coordinate and momentum operators, respectively. We apply it to study mutual converting formulae among Q-P ordering, P-Q ordering and Weyl ordering of operators. In this way, the contents of phase space quantum mechanics can be enriched. The formula of the Weyl ordering of operators expansion and the technique of integration within the Weyl ordered product of operators are used in this discussion. 展开更多
关键词 Wigner operator Weyl ordering two-fold integration transformation
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Mixture of a New Integral Transform and Homotopy Perturbation Method for Solving Nonlinear Partial Differential Equations 被引量:1
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作者 Artion Kashuri Akli Fundo Matilda Kreku 《Advances in Pure Mathematics》 2013年第3期317-323,共7页
In this paper, we present a new method, a mixture of homotopy perturbation method and a new integral transform to solve some nonlinear partial differential equations. The proposed method introduces also He’s polynomi... In this paper, we present a new method, a mixture of homotopy perturbation method and a new integral transform to solve some nonlinear partial differential equations. The proposed method introduces also He’s polynomials [1]. The analytical results of examples are calculated in terms of convergent series with easily computed components [2]. 展开更多
关键词 HOMOTOPY PERTURBATION Methods A NEW integral transform Nonlinear Partial Differential Equations He’s POLYNOMIALS
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A Solution of the Burger’s Equation Arising in the Longitudinal Dispersion Phenomenon in Fluid Flow through Porous Media by Mixture of New Integral Transform and Homotopy Perturbation Method 被引量:1
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作者 Kunjan Shah Twinkle Singh 《Journal of Geoscience and Environment Protection》 2015年第4期24-30,共7页
The main aim of the paper is to examine the concentration of the longitudinal dispersion phenomenon arising in fluid flow through porous media. These phenomenon yields a partial differential equation namely Burger’s ... The main aim of the paper is to examine the concentration of the longitudinal dispersion phenomenon arising in fluid flow through porous media. These phenomenon yields a partial differential equation namely Burger’s equation, which is solved by mixture of the new integral transform and the homotopy perturbation method under suitable conditions and the standard assumption. This method provides an analytical approximation in a rapidly convergent sequence with in exclusive manner computed terms. Its rapid convergence shows that the method is trustworthy and introduces a significant improvement in solving nonlinear partial differential equations over existing methods. It is concluded that the behaviour of concentration in longitudinal dispersion phenomenon is decreases as distance x is increasing with fixed time t > 0 and slightly increases with time t. 展开更多
关键词 Longitudinal Dispersion Phenomenon Porous Media NEW integral transform HOMOTOPY PERTURBATION Method
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Some New Applications of Elzaki Transform for Solution of Linear Volterra Type Integral Equations 被引量:1
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作者 Saad Sharjeel Mushtaq Ahmed Khan Barakzai 《Journal of Applied Mathematics and Physics》 2019年第8期1877-1892,共16页
Volterra type integral equations have diverse applications in scientific and other fields. Modelling physical phenomena by employing integral equations is not a new concept. Similarly, extensive research is underway t... Volterra type integral equations have diverse applications in scientific and other fields. Modelling physical phenomena by employing integral equations is not a new concept. Similarly, extensive research is underway to find accurate and efficient solution methods for integral equations. Some of noteworthy methods include Adomian Decomposition Method (ADM), Variational Iteration Method (VIM), Method of Successive Approximation (MSA), Galerkin method, Laplace transform method, etc. This research is focused on demonstrating Elzaki transform application for solution of linear Volterra integral equations which include convolution type equations as well as one system of equations. The selected problems are available in literature and have been solved using various analytical, semi-analytical and numerical techniques. Results obtained after application of Elzaki transform have been compared with solutions obtained through other prominent semi-analytic methods i.e. ADM and MSA (limited to first four iterations). The results substantiate that Elzaki transform method is not only a compatible alternate approach to other analytic methods like Laplace transform method but also simple in application once compared with methods ADM and MSA. 展开更多
关键词 Elzaki transform LINEAR VOLTERRA integral Equation Adomian Decomposition METHOD METHOD of Successive Approximation Laplace Elzaki DUALITY (LED)
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Heat Flux Analysis in Electrical Transformers through Integral Operators of Mechanics 被引量:1
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作者 Francisco Bulnes Alejandro R. Tello Máximo Livera 《Modern Mechanical Engineering》 2014年第2期84-107,共24页
Considering the continuous functioning of a power transformer under charge of high capacity of 50 MVA, predicted studies are proposed to be performed of their thermal behavior under perma nent and variable regimens of... Considering the continuous functioning of a power transformer under charge of high capacity of 50 MVA, predicted studies are proposed to be performed of their thermal behavior under perma nent and variable regimens of flow of charge, using noninvasive methods based in integral trans forms that measure and determine parameters of geometrical, analytical and physical type of the transformer. In before works, we have studied a basic geometry of a winding composed of high and low voltage sections with a uniform heat generation and heat convection boundary conditions. The heat conduction equation representing the phenomena of heat generation in a cylindrical structure was solved by using an integral transform. In this sense, this new study considers the basic geometry composed of a three cylindrical windings (high and low voltage turns) and a rec tangular core. Thus it is proposed to solve magnetic flow equations using integral transforms (Han kel transforms and Bessel integrals) in order to obtain the heat source distribution in the core due to the magnetization currents which are developed in function of the magnetic field flow equations. Based on this, it is proposed as a second step to use this heat source distribution to obtain the corresponding temperature distribution in the core by solving the cylindrical heat conduction equation for the core (cylindrical). Bearing this in mind, it is proposed finally to solve the 3D cylindrical heat conduction equation for the one winding using the calculated heat convection coefficients, the conductivity of the winding, behavior of the mineral oil and the non uniform winding heat generation predicted in recent researches. This equation will be solved by using integral methods (Radon, Hankel and Fourier transforms). This methodology will be useful to establish a new design of a power transformer based on the values of their integrals and the results that throw the inverse methods for this case. Finally if possible we will use the programs of Fluent and/or Phoenics for the validation of functional proposed models of prediction and prevention of heat flow and charge based on the obtained results. 展开更多
关键词 Power transformer Thermal Model CRITICAL Temperature POINTS integral transforms to Heat FLUX Magnetic FLUX
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FTransCNN:基于模糊融合的Transformer-CNN不确定性医学图像分割模型
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作者 王海鹏 丁卫平 +3 位作者 黄嘉爽 鞠恒荣 曹金鑫 刘传升 《小型微型计算机系统》 CSCD 北大核心 2024年第6期1426-1435,共10页
准确的医学图像分割对于疾病的诊断和治疗至关重要,将多个模型提取的分割特征进行联合使用时存在异质性、不确定性等问题,针对这一问题,本文提出了一种基于模糊融合策略的Transformer-CNN模型(FTransCNN).首先以CNN和Transformer作为骨... 准确的医学图像分割对于疾病的诊断和治疗至关重要,将多个模型提取的分割特征进行联合使用时存在异质性、不确定性等问题,针对这一问题,本文提出了一种基于模糊融合策略的Transformer-CNN模型(FTransCNN).首先以CNN和Transformer作为骨干网络,并行提取图片的特征信息;其次使用通道注意力促进Transformer全局关键信息,使用空间注意力增强CNN特征局部细节;接着应用Hadamard乘积对来自两个分支特征之间的细粒度交互进行建模,用Choquet模糊积分抑制融合特征的异质性以及融合特征的不确定性;然后使用Fuzzy Attention Fusion Module(FAFM)分级上采样,有效地捕获低级空间特征和高级语义上下文;最后反卷积得到最终的分割结果.在Chest X-ray数据集、Kvasir-SEG数据集和DRIVE数据集上的实验效果表明,FTransCNN与其它深度分割模型相比,在分割任务上有更好的效果. 展开更多
关键词 CHOQUET模糊积分 模糊融合 医学图像分割 transformER CNN
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A FAMILY OF INTEGRABLE SYSTEMS OF LIOUVILLE AND LAX REPRESENTATION, DARBOUX TRANSFORMATIONS FOR ITS CONSTRAINED FLOWS
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作者 张玉峰 张鸿庆 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第1期26-34,共9页
A family of integrable systems of Liouville are obtained by, Tu pattern. Using higher-order potential-eigenfunction constraints, the integrable systems are factorized to two x- and t(n)-integrable Hamiltonian systems ... A family of integrable systems of Liouville are obtained by, Tu pattern. Using higher-order potential-eigenfunction constraints, the integrable systems are factorized to two x- and t(n)-integrable Hamiltonian systems whose Lax representation and three kinds of Darboux transformations are presented. 展开更多
关键词 integrable system potential-eigenfuction constraint Lax representation Darboux transformation
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Exact solutions of the Klein-Gordon equation with ring-shaped oscillator potential by using the Laplace integral transform
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作者 Sami Ortakaya 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第7期108-112,共5页
We present exact solutions for the Klein Gordon equation with a ring-shaped oscillator potential. The energy eigenvalues and the normalized wave functions are obtained for a particle in the presence of non-central osc... We present exact solutions for the Klein Gordon equation with a ring-shaped oscillator potential. The energy eigenvalues and the normalized wave functions are obtained for a particle in the presence of non-central oscillator potential. The angulm" functions are expressed in terms of the hypergeometric functions. The radial eigenfunetions have been obtained by using the Laplace integral transform. By means of the Laplace transform method, which is efficient and simple, the radial Klein-Gordon equation is reduced to a first-order differential equation. 展开更多
关键词 ring-shaped oscillator Klein-Gordon equation Laplace integral transform bound states
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Certain Integral Transforms of Generalized k-Bessel Function
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作者 Kottakkaran Sooppy Nisar Waseem Ahmad Khan Mohd Ghayasuddin 《Analysis in Theory and Applications》 CSCD 2018年第2期165-174,共10页
The objective of this note is to provide some(potentially useful) integral transforms(for example, Euler, Laplace, Whittaker etc.) associated with the generalized k-Bessel function defined by Saiful and Nisar [3]. We ... The objective of this note is to provide some(potentially useful) integral transforms(for example, Euler, Laplace, Whittaker etc.) associated with the generalized k-Bessel function defined by Saiful and Nisar [3]. We have also discussed some other transforms as special cases of our main results. 展开更多
关键词 GAMMA FUNCTION k-Bessel FUNCTION generalized k-Bessel FUNCTION integral transforms
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APPLYING FAST WALSH TRANSFORM TECHNIQUE TO ANALYZE HIGH-SPEED DIGITAL INTEGRAL TRANSMISSION LINES
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作者 戚颂新 杨铨让 《Journal of Electronics(China)》 1993年第3期227-234,共8页
A new approach, based on the waveform relaxation technique and fast Walsh trans-form, is presented to analyze the coupled loosy transmission lines (CLTL) with arbitrary terminalnetworks. The simulation accuracy of the... A new approach, based on the waveform relaxation technique and fast Walsh trans-form, is presented to analyze the coupled loosy transmission lines (CLTL) with arbitrary terminalnetworks. The simulation accuracy of the new method can be greatly improved, the disadvantagewhich always exists in previous methods can be avoided and a considerable saving in time andmemory of CPU is obtained. 展开更多
关键词 integral transmission line FAST WALSH transform WAVEFORM RELAXATION
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