fourier wave 中文意思是什麼

fourier wave 解釋
傅里葉波
  • fourier : n 1 傅立葉〈姓氏〉。2 Francois Marie Charles Fourier 弗朗瓦斯馬利沙利傅立葉〈1772 1837,法國空想...
  • wave : n 〈美海軍〉女志願軍人〈見 WAVES 條〉。n 1 波浪;碎浪; 〈the wave(s)〉 〈詩〉海。2 波動;波狀...
  1. This multi - purpose optical metering system had adopted the twyman - green interferometric system as its center, containing an advanced digital wave surface interferometry and a kind of homodyne interferometer displacement testing method with nanometer - sized capacity. at the same time, many wide - applied metering technology, for example, the diffracted field ( fringe ) measurement, co - focal lens system, optical fiber sensors and 4f ( focal distance ) space filter system which can embody the chief principle of fourier optics well, were combined into it successfully. this instrument can firstly offer and show modern optical testing method in the laboratory for majors of information processing, instrument science, measuring and testing technology and automatic technology

    該多功能激光光電實驗系統以泰曼-格林干涉( twyman - green )光路作核心,包括先進的數字波面干涉技術和一種基於空間干涉原理的、納米解析度零差干涉儀位移測量方法,同時將多種新穎、工程實用價值高的測量技術和光路如衍射測量、共焦顯微技術、光纖傳感技術以及反映傅立葉光學基本光學原理的4f空間濾波系統也組合進去。
  2. As an example of the technique, let's compute the fourier series which corresponds to a square wave.

    作為這種方法的一個例子,讓我們計算一個方波的傅里葉級數。
  3. In this paper, a method assessing harmonic impedance by synchronously layered distortion waves is proposed, which is based on the " fluctuations method " - a simple and effective means. however the method is based on the fourier transform, which can just precisely analyze the signals whose cycle is integer times as broad as that of fundamental wave. with sampling windows widening, the variations of distorted signals in a fundamental period are weakened

    本文是以一種被廣泛採用的非干預式諧波阻抗估計方法? ? 「波動量」法,的基礎上,針對現有方法以直接的fourier變換為分析工具,只能對基波周期的整數倍窗口采樣信號進行分析,畸變信號在一個基波周期內的變化隨采樣窗口增大而被弱化,並且,諧波次數越高,解析度就越低,大大限制了諧波阻抗估計的準確性的提高。
  4. One is the non - orthogonal gabor - daubechies frame, or g - d frame, a complete set of discrete window fourier functions which are constructed by space - shifting and harmonically modulating a gaussian window. although a g - d frame is not an orthogonal basis, it bears considerable advantages for the study of physical problems, especially those related to the wave field extrapolation, due to the optimal localization properties of the gaussian window function under the heisenberg uncertainty principle

    其一為將高斯窗函數經平移和調制而構成的一組窗口富里葉框架( gabor - daubechies框架,或g - d框架)基本函數,另一種為在富里葉分析和小波包理論基礎上發展起來的局部餘弦基函數。
  5. And non - fourier heat conduction is encountered. when the wavelength of the heat carrier is comparable to the characteristic length of the structures, or the time of heat conduction is shorter than that required for reaching the state of thermal equilibrium, the heat conduction has wave characteristics

    當載熱體的微時間尺度與能量激發特徵時間相比擬時,或者傳熱發生的時間比達到熱力學平衡態所需的時間短時,熱傳導就可能出現波動性質。
  6. Advanced mathematical technologies, especially the newly developed wavelet transform and the frame theory, provide a solid foundation for such an effort. the ray - theory based beam - summation method, such as the complex source - generated beam and the gaussian beam methods, and the local phase - space domain ( beamlet domain ) wave field extrapolation methods employing windowed fourier transform ( wft ) or wavelet transform are proposed consequently

    基於射線理論的高頻漸近射束(復射束、高斯射束)疊加方法,以窗口富里葉變換( wft )以及小波變換為基礎的局部相位-空間域(小波束域)波場外推方法等相繼產生。
  7. Essential to their utility is the requirement that the evolution of the basic functions through the propagation environment constitutes a simplified problem with an exact or approximate closed form solution to the original wave equation. the evolution of a spatial fourier harmonic through a homogeneous medium is governed by a reduced wave equation, obtained by applying the fourier transform to the helmholtz equation, with a simple and well - known solution - the plane wave

    這些方法均採用一組具有全局特性的基本函數對波場進行分解,如占據整個空間的富氏調諧函數或充滿各個方向的dirac函數(點源) ,並通過求解基本函數滿足波動方程的精確解或近似解來達到波場外推的目的。
  8. Comprehensively discuss the issues in application, adaptive condition and performance, propose a fast arithmetic of forward modeling and depth migration in common shot gathers with one - way acoustic wave equation based on vrselrf, and verify the arithmetic by numerical simulation. concisely discuss the cause of the creation of evanescence and the problem of lateral amplitude discontinuity result from it. fourthly, use the reflectivity model, computed to describe the fracture model, with the formula of computation reflectivity based on elastic - acoustic approximation, and the wavelet model computed by the method, wavelet creation with fourier transform, we proposed, in conjunction with vrselrf wavefield extrapolation operator

    第三,將頻率波數域穩定的變參考慢度rytov近似廣義屏波場延拓運算元( vrselrf )應用於疊前與疊后正演模擬、疊前與疊后深度偏移,對演算法應用中應注意的問題、適用范圍、性能等作了較為全面的論述;提出了基於vrselrf的單程聲波方程共炮記錄正演模擬和深度偏移快速演算法,並通過數值模擬試驗對演算法進行了驗證;簡要地討論了倏逝波的產生原因及其帶來的橫向振幅不連續性問題。
  9. Thermal wave scattering of subsurface defects in solids based on non - fourier ' s models

    固體中亞表面缺陷的非傅里葉熱波散射問題
  10. The numerical method based on the coupling of the finite difference method in time domain with the discrete fast fourier transform is applied to calculate the first four eigenfrequencies and eigenfunctions of the six - cavity with open boundary. the absorbing boundary condition for tem wave is tested numerically, and it is applied to writing the code. the cold testing of the cavity is done and the results are good agreement with the numerical results

    計算x波段六腔開放腔前四個模式的場分佈;根據第二章公式分別計算x波段六腔開放腔前四個模式的電子負載電導並總結了這四種工作模式渡越效應的規律,基於這種小信號理論分析了x波段渡越輻射振蕩器,得到了工作模式及可能產生的模式競爭。
  11. An algorithm that can extract harmonics " amplitudes using morlet wavelets is put forward. compared with the full - wave fourier algorithm, the algorithm proposed in this article is more stable when the frequency of electric network flutters. meanwhile the algorithm has the rapidity of giving out the

    在電網頻率波動情況下,通過比較說明短窗morlet復小波演算法在頻率波動過程中具有比傅氏演算法更穩定的特點,同時也可以達到1 3周波內完成的快速性。
  12. Thirdly, the method to calculate the 3 - d dynamic responding of layered transversely isotropic saturated soils to an arbitrary buried source in cylindrical coordinate as well as to an arbitrary harmonious source in rectangular coordinate is presented respectively. based on biot ' s wave theory, the 3 - d wave equations in cylindrical coordinate for transversely isotropic saturated poroelastic media are transformed into a group of governing different equations with 1 - order by the fourier expanding with respect to azimuth and hankel integral transform method or by the double fourier transform method with respect to horizontal coordinates in rectangular coordinate. then, transfer matrixes within layered media are derived under the continuous conditions, drainage conditions and the boundary conditions

    基於飽和土的biot波動理論,通過fouricr變換,將橫觀各向同性飽和土三維非軸對稱波動方程轉化為一組一階常微分方程組,再經har止el變換,建立問題的狀態方程,求解狀態方程得到傳遞矩陣;利用傳遞矩陣,結合飽和層狀地基的邊界條件、排水條件及層間接觸和連續條件,首次給出層狀橫觀各向同性飽和地基在任意地展力作用下的三維非軸對稱動力響應的解析解。
  13. The unfocused hologram of lensless fourier holography are also discussed, and a way to revise the reconstruction image of unfocused hologram is presented. ( 2 ) the reconstruction of image plane hologram is analyzed by plane wave theory. the image plane holograms of transparent and opaque objects are also obtained by using fibers

    ( 2 )用角譜理論分析了像面全息圖的再現過程,採用光纖傳光分別拍攝了透射和反射物體的像面全息圖,並利用頻域法對全息圖進行數值再現,得到了物體較清晰的再現像。
  14. The migration results of the synthetic and ocean field datasets show that this method is correct and effective. several prestack depth migration methods are proposed and unified to the synthetic source record migration method. these methods include plane wave migration with fourier finite difference ( ffd ) extrapolator, maximum energy plane wave migration and prestack migration with phase encoding of areal shot records

    通過對本文提出的平面波傅立葉有限差分疊前深度偏移方法、最大能量面炮記錄疊前深度偏移方法和相位編碼面炮記錄疊前深度偏移方法的研究,試算和對比,提出了合成震源三原則,根據這些原則,提出了合成震源概念和合成震源記錄疊前深度偏移方法。
  15. The method and theory of time - frequency analysis based on short - time fourier transformation are studied and the wave arrival points of easy component are determined by making software and using time - frequency analysis

    研究了基於短時傅里葉變換的時頻分析方法理論,並通過編制軟體利用時頻分析方法確定各組分波的波至點。
  16. In order to utilize the atmospheric duct phenomena, and to make the electronic reconnaissance facilities more effective and the status of battlefield more advantageous, on the basis of classification of the atmospheric duct, first the model for evaluating the effective detective zone of electronic reconnaissance facility is established, then the numerical value simulation method of electromagnetic wave propagation under the condition of surface duct calculated with parabolic equation and fourier arithmetic is presented, and finally the influences of atmospheric duct on electronic reconnaissance facility is analyzed

    為充分利用大氣波導條件,發揮電子偵察設備效能,使戰場態勢向有利於己方方向轉化,在介紹大氣波導分類的基礎上,建立評估電子偵察設備的有效探測區的模型,給出用拋物線方程及其分佈傅里葉演算法計算電磁波在表面波導條件下傳播的數值模擬方法,並分析了大氣波導對電子偵察設備的影響情況。
  17. One is to use fourier transformation to convert the source signal from time domain to frequency domain and to discard high frequency harmonious components upwards of 19 ( gb / t14953 - 93 d5. 3 demanding ), then to have static huffman coding to the quantized char array which is composed of reserved direct current component and basic wave and each high frequency " s amplitudes and angles. the other is to use discrete wavelet transformation to convert the source signal from time domain to frequency domain and to set the high frequency coefficients that its absolute value is smaller than the given threshold to zero, then to have dynamic huffman coding to the quantized char array which is composed of multiple, wavelet ' s level, datum length, low frequency coefficients and reserved high frequency coefficients. mass simulinks and analyses under the two circumstances have done to show that data compression ratio is small and the relative error is also small and within the permission of engineering and the compression problem can be solved in theory of measured datum of power system

    第一種情況的壓縮方法為:採用傳統的傅立葉變換把原始信號從時間域變換到頻率域,舍棄20次及其以上的高次諧波成分(保證了gb / t14953 ? 93d5 . 3要求) ,然後對保留的直流分量、基波和各次諧波的幅值和相角數據量化后和量化時分別乘以的倍數系數構成一個數組,以字元形式保存,採用靜態huffman編碼對變換數據進行壓縮;採用離散小波變換把原始信號從時間域變換到頻率域,然後對分解得到的高頻系數進行閾值量化處理,對乘以的倍數系數、小波變換的階數、小波變換后的低頻、各級高頻以及原始數據長度、量化后的低頻系數以及保留的高頻系數大小、位置構成一個數組,以字元形式保存,採用動態huffman編碼對這個文件進行壓縮。
  18. The main contents are : ( 1 ) the recording and numerical reconstruction of lensless fourier hologram are analyzed by spherical wave theory

    主要內容包括: ( 1 )用球面波理論分析了無透鏡傅里葉變換全息圖的記錄和再現過程。
  19. By 1 - d fourier transform, we could analyze wave spectrum and get wave speed by computing phrase shift, then calculate the velocity of the wind, so we can avoid the problem of " sub - pixel motion "

    使用傅立葉相位分析法,對示蹤雲進行頻域波譜分析,由諧波的相位變化計算波速,繼而得出風速,能夠避免「亞像素尺度位移」問題,提高導風的精確度。
  20. From 1920s up to now, various techniques and methods for wave field decomposition, propagation and migration / imaging have been well developed, such as the kirchhoff asymptotic method, frequency - wavenumber domain phase - shift and phase - shift - plus - interpolation methods, and the one - way wave equation based phase - screen and generalized screen methods, etc. wave field extrapolation in these methods is implemented based on the expansion of the wave field by sets of basic functions like spatial fourier harmonies, modes, and green ' s functions

    自上個世紀二十年代至今,波場分解、傳播與偏移成像技術經歷了將近一個世紀的發展,形成了多種不同的方法,如kirchhoff波動方程高頻近似解方法,頻率-波數域的相移( phase - shift )方法和相移-內插( pspi )方法,以及在混合域中基於單向波動方程的相位屏、廣義屏方法等。
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