检索结果-南通市图书馆

Bispectra-mellin transform and its application in Doppler-distorted Pulsar Signals

在线全文

学校读者我要写书评

暂无评论

Bispectra-Mellin transform and its application in Doppler-di...

Algebraic Properties of Toeplitz and Small Hankel Operators on the Harmonic Bergman Space

第三届中国卫星导航学术年会

作者： Su Zhe*, Zhang Lixin, Qian Xiaoping, Xu Qibing, Li Yisong China Academy of Space Technology (Xi’an), Xi’an 710100, China

The bispectra based pulsar integrated pulse profile recognition algo- rithm performs poorly when the pulsar signal received by spacecraft is distorted by Doppler effect. In order to improve the recognition rate, this paper proposes a novel pulsar integrated pulse profile recognition algorithm based on the bispectra-mellin （BM） transform. By combining bispectra and mellin transform together, the BM transform is independent of both translation and scale changes, and robust to Gaussian noise, which is especially suitable for pulsar signal recognition in X-ray pulsar deep space navigation system. Several experiments dealing with different pulsars have been carried out to illustrate the applicability of this algorithm, even when the signal is Doppler-distorted.

关键词： pulsar bispectra mellin transform low-pass filtering property Doppler

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2014年第8期30卷 1395-1406页

作者： Hong Yan GUAN Yu Feng LU School of Mathematical Sciences Dalian University of Technology School of Mathematics and Systems Science Shenyang Normal University

In this paper,we discuss some algebraic properties of Toeplitz operators and small Hankel operators with radial and quasihomogeneous symbols on the harmonic Bergman space of the unit disk in the complex plane *** solve the product problem of quasihomogeneous Toeplitz operator and quasihomogeneous small Hankel ***,we characterize the commutativity of quasihomogeneous Toeplitz operator and quasihomogeneous small Hankel operator.

关键词： Toeplitz operator small Hankel operator quasihomogeneous symbols harmonic Bergman space mellin transform

Modeling multilook polarimetric SAR images with heavy-tailed rayleigh distribution and novel estimation based on matrix log-cumulants

在线全文

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2013年第6期56卷 60-73页

作者： LIU Tao CUI HaoGui MAO Tao XI ZeMin GAO Jun Electronic School of Engineering Naval University of Engineering Fourth Department Headquarters of Navy

With the improvements in modern radar resolution,the Gaussian-fluctuation model based on the central limit theorem does not accurately describe the scattering echo from *** contrast,the heavytailed Rayleigh distribution,based on the generalized central limit theorem,performs well in modeling the synthetic aperture radar(SAR) images,whereas its application to multi-look image processing is *** describe successful modeling of multilook polarimetric SAR images with the heavy-tailed Rayleigh distribution and present novel parameter estimators based on matrix log-cumulants for the heavy-tailed Rayleigh distribution including the equivalent number of looks(ENL).First,a compound variable of heavy-tailed Rayleigh distribution is divided into a product of a positive alpha-stable variable and a complex Gaussian *** parameter estimations of the characteristic exponent and scale parameter based on log-cumulants in a single polarization channel are then ***,the matrix log-cumulants(MLCs) for full polarization in multilook images are obtained,which can be applied to estimate model ***,a novel ENL estimator based on MLC is presented that describes the model more *** to all other multivariable product models,this estimator performs better than existing ***,calculations on both simulated and real data are performed that give good fits with theoretical *** processing in one image with a fixed pixel number can improve parameter estimations over single-look *** heavy-tailed Rayleigh model with its parameter estimation provides a new method to analyze the multilook polarimetric SAR images for target detection and classification.

关键词： heavy-tailed Rayleigh distribution multilook polarimetric synthetic aperture radar mellin transform matrix log-cumulants

CONCENTRATION DISTRIBUTION OF FRACTIONAL ANOMALOUS DIFFUSION CAUSED BY AN INSTANTANEOUS POINT SOURCE

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2003年第11期24卷 1302-1308页

作者：段俊生徐明瑜 Department of Basic Sciences Tianjin University of Commerce Tianjin 300134 P.R.China Institute of Mathematics and Systematical Science Shandong University Jinan 250100 P. R. Chinahe Fox function expression and the analytic expression for the concentration distribution of fractional anomalous diffusion caused by an instantaneous point source in n-dimensional space (n= 1 2 or 3) are derived by means of the condition of mass conservation the time-space similarity of the solution Mellin transform and the properties of the Fox function . And the asymptotic behaviors for the solutions are also given .

The Fox function expression and the analytic expression for the concentration distribution of fractional anomalous diffusion caused by an instantaneous point source in n-dimensional space (n= 1, 2 or 3) are derived by means of the condition of mass conservation , the time-space similarity of the solution , mellin transform and the properties of the Fox function . And the asymptotic behaviors for the solutions are also given .

关键词： instantaneous point source anomalous diffusion fractional calculus Fox function mellin transform

Commuting Toeplitz Operators on Fock-Sobolev Spaces of Negative Orders

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2023年第10期39卷 1989-2005页

作者： Hong Rae CHO Han-Wool LEE Department of Mathematics Pusan National UniversityBusan 46241Korea

In the setting of Fock-Sobolev spaces of positive orders over the complex plane,Choe and Yang showed that if the one of the symbols of two commuting Toeplitz operators with bounded symbols is non-trivially radial,then the other must also be *** this paper,we extend this result to the Fock-Sobolev space of negative order using the Fock-type space with a confluent hyper geometric function.

关键词： Fock–Sobolev spaces commutator of Toeplitz operators mellin transform Confluent Hypergeometric Function

Trace of heat kernel,spectral zeta function and isospectral problem for sub-laplacians

在线全文

学校读者我要写书评

暂无评论

Science China Mathematics 2009年第12期52卷 2570-2589页

作者： CHANG Der-Chen YEUNG Sai-Kee Department of Mathematics Georgetown University Department of Mathematics Purdue University

In this article, we first study the trace for the heat kernel for the sub-Laplacian operator on the unit sphere in ? n+1. Then we survey some results on the spectral zeta function which is induced by the trace of the ... 详细信息

关键词： sub-Laplacian heat kernel CR-isospectral problem Riemannian zeta function mellin transform pseudo-hermitian structure Primary: 53C17 Secondary: 34K10, 35H20

Krätzel Function and Related Statistical Distributions

在线全文

学校读者我要写书评

暂无评论

Communications in Mathematics and Statistics 2014年第3期2卷 413-429页

作者： T.Princy Centre for Mathematical Sciences Arunapuram P.O.Pala 686574KeralaIndia Department of Statistics Banaras Hindu University(B.H.U)Varanasi 221005India

The Krätzel function has many applications in applied analysis,so this function is used as a base to create a density function which will be called the Krätzel *** density is applicable in chemical physics,Hartree–Fock energy,helium isoelectric series,statistical mechanics,nuclear energy generation,etc.,and also connected to Bessel *** main properties of this newfamily are studied,showing in particular that it may be generated via mixtures of gamma random *** basic statistical quantities associated with this density function such as moments,mellin transform,and Laplace transform are *** of Krätzel distribution to reaction rate probability integral in physics,inverse Gaussian density in stochastic processes,Tsallis statistics and superstatistics in non-extensive statistical mechanics,mellin convolutions of products and ratios thereby to fractional integrals,synthetic aperture radar,and other areas are pointed out in this ***,we extend the Krätzel density using the pathway model of Mathai,and some applications are also *** new probability model is fitted to solar radiation data.

关键词： Laplace transform Krätzel function mellin transform H-function Krätzel density Pathway model

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

时间分数阶扩散-反应方程

高等学校计算数学学报 2005年第3期27卷 79-85页

作者：卢旋珠刘发旺厦门 361005 福州大学数学系厦门大学数学系福州 350002

当前,对含有非整数阶导数和积分的方程的研究正引起越来越多学者的关注,这类分数阶导数和积分将广泛应用于科学和工程的各个领域.在标准扩散方程中用α(0<α≤1)阶分数阶导数替代一阶导数,用β(0<β≤2)阶分数阶导数替代二阶导数,得到空... 详细信息

当前,对含有非整数阶导数和积分的方程的研究正引起越来越多学者的关注,这类分数阶导数和积分将广泛应用于科学和工程的各个领域.在标准扩散方程中用α(0<α≤1)阶分数阶导数替代一阶导数,用β(0<β≤2)阶分数阶导数替代二阶导数,得到空间-时间分数阶扩散方程.近年来,许多学者研究了空间-时间分数阶扩散方程,时间分数阶扩散-波动方程,时间分数阶扩散方程,空间分数阶扩散方程,时间分数阶对流-扩散方程,以及空间分数阶对流-扩散方程.

关键词： fractional order diffusion-reaction equation mellin transform Laplace transform Fox function Green function.