transform,fourier 《英文msh词典》Transform,Fourier ; [入口词] Transform,Fourier ; [主题词] Fourier Analysis ; [英文释义] Analysis based on the mathematical function first formulated by Jean-Baptiste-Joseph Fourier in 1807. The function,known as the Fourier transform,describes the sinusoidal pattern of any fluctuating pattern in the physical world in terms of its amplitude and its phase. It has broad applications in biomedicine,e.g.,analysis of the x-ray crystallography data pivotal in identifying the double helical nature of DNA and in analysis of other molecules,including viruses,and the modified back-projection algorithm universally used in computerized tomography imaging,etc. (From Segen,The Dictionary of Modern Medicine,1992)
Direct digital frequency synthesizer ( dds ) is an apparatus to generate wave on the required frequency . it provides high frequency resolution, rapid frequency transforma-tion and other superiority 直接数字频率合成器是现代频率合成的主要工具,它有频率分辨率高,频率转化快等众多优点。
This paper integrates linear affine transformation and nonlinear affine transforma-tion's approach ability . integrated affine transformation not only inherits the linear affine transformation's low bit rate merit, but also inherits the nonlinear affine transformation's approach ability . the method proposed in this paper is a new method, and never be proposed in other papers 本硕士论文综合了线性仿射变换和非线性仿射变换的逼近能力,采用混合型的仿射变换既能发扬线性仿射变换的低比特率的优点,又能发扬非线性仿射变换的相似逼近能力,提高重建质量,本算法是一种新型的算法,文献中尚未提及。