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The digital computer Z4 which was installed in 1950 at the Institute for Applied Mathematics of the ETH Zurich was a remarkable instrument in many respects.


Quantum information theory is a new interdisciplinary research field related to quantum mechanics, computer science, information theory, and applied mathematics.


The Wiberg algorithm is a numerical algorithm developed for the problem in the community of applied mathematics.


To allow direct comparisons with algorithms from the applied mathematics and computer vision communities, we consider both inhomogeneous and homogeneous systems.


Supercomputing applications to the numerical modeling of industrial and applied mathematics problems

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 Wavelet analysis is a rapidly developing domain of applied mathematics. It has been used in turbulence, and several methods are presented to study the coherent structure in turbulence. In this paper, two conclusions are made from the relation between wavelet energy spectrum and Fourier energy spectrum. The first conclusion is that the peak height of wavelet energy spectra of sine and cosine waves is proportional to their scale, and the second is that the peak width of wavelet energy spectra of sine and... Wavelet analysis is a rapidly developing domain of applied mathematics. It has been used in turbulence, and several methods are presented to study the coherent structure in turbulence. In this paper, two conclusions are made from the relation between wavelet energy spectrum and Fourier energy spectrum. The first conclusion is that the peak height of wavelet energy spectra of sine and cosine waves is proportional to their scale, and the second is that the peak width of wavelet energy spectra of sine and cosine waves is proportional to their scale. Based on wavelet analysis and these two conclusions, a new energy maxima criterion of coherent structure, P(a m)/ a m=max a >0 P(a )/ a , where P is wavelet energy spectrum, which can extract several coherent structures of close scale in turbulence and determine their scales, is presented. At the same time, Morlet wavelet is found to have a higher resolution ratio than Mexican hat wavelet and some orthonormal wavelets, such as Daubechies, Symlets, Meyer and Coiflets, which can distinctly distinguish fundamental wave from subharmonic. So Morlet wavelet is much suited to detect coherent structure in turbulence. The new criterion is validated with simulative signals which are constructed by adding three kinds of noises with different energy spectra exponents (r=0, 1.00, 1.67) to y=sin(16π x )+sin(32π x ) and keeping the intensity of coherent structure about 0.1. The results show that the new criterion can distinguish fundamental wave from subharmonic based on simulative signals with a small coherent structure intensity. At last, the new criterion is validated with threedimensional fluctuation velocities of a round jet flow near the nozzle exit. The results show that the scale of coherent structure determined by the new criterion is equivalent to the integral scale, and the coherent structure is a large vortex.  根据对小波能谱的分析 ,提出了基于小波分析的辨识相干结构的能量最大准则 ,能分辨湍流信号中多个相近尺度的相干结构 ;根据对不同小波的计算 ,发现常用小波中以Morlet小波的分辨率最高 ,能有效地分辨基波与次谐波 ;并用模拟信号和圆形湍流射流边界层内的实验数据对上述结论进行了验证 .  Based on intensive investigation and analysis of lowturbulence wind tunnel,a wind tunnel has been set up at Shanghai Institute of Applied Mathematics and Mechanics.Some notable characteristics include lowturbulence,adaptable turbulence and low noise.Aerodynamic design of the main parts including the inclined flow blower,the settling chamber,the contraction section and the working section are described.Together with other experimental facilities,the wind tunnel can be used in the experiments of velocity... Based on intensive investigation and analysis of lowturbulence wind tunnel,a wind tunnel has been set up at Shanghai Institute of Applied Mathematics and Mechanics.Some notable characteristics include lowturbulence,adaptable turbulence and low noise.Aerodynamic design of the main parts including the inclined flow blower,the settling chamber,the contraction section and the working section are described.Together with other experimental facilities,the wind tunnel can be used in the experiments of velocity and pressure measurement for teaching,and in aeronautics and astronautics,building and bridge construction,pollution, automobile industry,etc.,for aerodynamic research.  通过对国内外现有低湍流风洞进行调研和分析,上海大学力学所建造了一座低湍流度低速风洞(以下简称SIAMM400).该风洞具有低湍流度、可变湍流度、低噪声等几个特色.在风洞的设计过程中,对其主要部件(包括斜流式风机、稳定段、收缩段、试验段等)进行详细的气动计算,给出了设计依据.风洞建成后,结合实验室内先进的测量手段,除了能满足模型的测压、测速、流态观测等教学实验外,还可以利用该风洞从事航空航天、桥梁建筑、环境污染、汽车等工业空气动力学研究工作.  
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