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61.
The Two-Dimensional Clifford-Fourier Transform   总被引:1,自引:0,他引:1  
Recently several generalizations to higher dimension of the Fourier transform using Clifford algebra have been introduced, including the Clifford-Fourier transform by the authors, defined as an operator exponential with a Clifford algebra-valued kernel. In this paper an overview is given of all these generalizations and an in depth study of the two-dimensional Clifford-Fourier transform of the authors is presented. In this special two-dimensional case a closed form for the integral kernel may be obtained, leading to further properties, both in the L 1 and in the L 2 context. Furthermore, based on this Clifford-Fourier transform Clifford-Gabor filters are introduced. AMS subject classification numbers: 42B10, 30G35 Fred Brackx received a diploma degree in mathematics from Ghent University, Belgium, in 1970 and a Ph.D. degree in mathematics from the same university in 1973. Since 1984 he is professor for mathematical analysis at Ghent University and currently he is leading the Clifford Research Group. His main interests are function theory and functional analysis for functions with values in quaternion and Clifford algebras. The research covers Clifford distributions, generalized Fourier, Radon and Hilbert transforms, orthogonal polynomials and multi-dimensional wavelets. Nele De Schepper received a diploma degree in mathematics from Ghent University, Belgium, in 2001. Since then she holds an assistantship at the Department of Mathematical Analysis of Ghent University and is a member of the Clifford Research Group. Her main interests are function theory and functional analysis for functions with values in Clifford algebras. The research covers generalized Fourier transforms, orthogonal polynomials and multi-dimensional wavelets. Frank Sommen received a diploma degree in mathematics from Ghent University, Belgium, in 1978, a Ph.D. degree in mathematics from the same university in 1980, and a habilitation degree in mathematical analysis in 1984. From 1978 until 1999 he was at the National Fund for Scientific Research (Flanders). Since 2000 he holds a Research professorship at Ghent University. His main interests are function theory and functional analysis for functions with values in quaternion and Clifford algebras. The research covers Clifford distributions, generalized Fourier, Radon and Hilbert transforms, orthogonal polynomials and multi-dimensional wavelets, algebraic analysis, hyperfunctions and radial algebra.  相似文献   
62.
结合国内外对碳钢CO2腐蚀影响因素的研究成果,采用模糊层次分析法对影响输油管道 CO2腐蚀的因素进行定量分析,明确界定出这些因素对二氧化碳腐蚀影响的相对重要性(权重),为后续制定经济有效的管道内腐蚀防护措施提供了客观依据。  相似文献   
63.
电力系统谐波检测的现状与发展   总被引:7,自引:0,他引:7  
准确、实时地对电力系统谐波进行检测有着重要的意义。本文根据电力系统谐波测量的基本方法,对近年来电力系统谐波检测的新方法进行了分析和评述。最后对电力系统的谐波测量进行了总结并提出了看法。  相似文献   
64.
A stochastic model for local disturbances, particularly for a temporal harmonic with random modulations in amplitude and/or phase, is proposed in this paper. Results for the second moment responses of a linear single-degree-of-freedom system to this type of stochastic loading demonstrate a significant change in response characteristics due to a small uncertainty. A local phenomenon may last much longer and resonance may be smeared to a broad range. Integrated with wavelet transform, the proposed approach may be used to model a random process with non-stationary frequency content. Especially, it can be effectively used for Monte Carlo simulation to generate large size of samples that have similar characteristics in time and frequency domains as a pre-selected mother sample has. The technique has a great potential for the case where uncertainty study is warranted but the available samples are limited.  相似文献   
65.
套保稠油油田火烧油层可行性分析   总被引:2,自引:1,他引:1  
从火烧油层的筛选标准、实际地质条件及室内物理模拟实验入手,对该油田火烧可行性进行了分析。分析结果认为,套保油田进行火烧总体上是可行的,在实际火烧时应避开底水的影响,火烧区域应选在构造高部位或仅烧其主力层。  相似文献   
66.
Identification of anthocyanins in the wine made of the Croatian autochthonous grape variety of Babić (Vitis vinifera L.) was carried out and their profile was determined by means of high-performance liquid chromatography with diode array and mass spectrometric detection. Dependence of anthocyanins content and profile on maceration treatment conditions was investigated. Statistically significant differences of anthocyanins concentration in wines Babić produced by various maceration treatments were confirmed by the use of multivariate analysis of variances. The investigation results indicated that the maceration temperature exerts higher influence on anthocyanins concentration than the duration of maceration. In addition, on the basis of anthocyanin composition and using different multivariate statistical analyses, differentiation of wines Babić according to maceration treatments was procured.  相似文献   
67.
针对加油站在油品进、销、存方面因管理和人为作弊而产生的损耗大问题,提出了解决办法:各环节交接手续要严密完备;发货方实施保量运输,选择信誉好的承运方;在销售、储存方面应加强管理,推行加油站计量员、账务员集中管理,主要账表电子表格化,及时上报主管部门,执行责任追究制并与效益工资挂钩。  相似文献   
68.
69.
基于有限状态的全周期序列混沌映射的研究   总被引:1,自引:1,他引:0  
在有限长度的数字计算机中,混沌迭代序列是一个有限周期序列,其相关性能远远低于理想序列。基于skew tent映射,提出一种离散化的有限状态混沌映射,它允许精确的数值计算,没有舍入误差,通过选择合适的参数,映射能产生全周期长度的序列。仿真实验表明,归一化的序列平均周期对计算机精度不敏感,生成的二进制序列具有良好的相关性能。  相似文献   
70.
试论循环水装置的经济性及其成本分析   总被引:2,自引:1,他引:1  
通过对循环水装置的投资和成本分析,阐述了建设该装置的经济性和社会意义。  相似文献   
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