fourier transformation 中文意思是什麼

fourier transformation 解釋
傅理葉變換
  • 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...
  • transformation : n 轉變,變化;變形;【生物學】(尤指昆蟲的)轉化,變態,改造,改革;變質;【數學】變換;【電學】...
  1. Optical 3 - d profilometry has been widely used for 3 - d sensing, machine vision, intelligent robots control, industry monitoring, biomedicine, dressmaking, etc. several 3 - d object profilometry methods, including moire technique ( mt ), phase - measuring profilometry ( pmp ), fourier transformation profilometry ( ftp ), modulation measurement profilometry ( mmp ) have been exhaustively studied

    光學三維傳感已廣泛應用於機器視覺,實物仿形,工業檢測,生物醫學等方面,在三維面形測量中,對莫爾輪廓術,位相測量輪廓術,付里葉變換輪廓術,調制度測量輪廓術這些方法已經進行了大量深入的研究。
  2. Fourier analysis has been changed to fit to analyze unsteady signal, which is represented by short - time fourier transformation. but in essence, the short - time fourier transformation is a method of ingle resolution because it uses an unchanged short - time widow function

    但從本質上講,短時傅里葉變換是一種單一解析度的信號分析方法,因為它使用一個固定的短時窗函數。
  3. Abstract : events contributing to the establishment of statistics the science of data and its chemical branch are epitomized. as the new chemical branch named chemometrics or chemstatistics has been disputed in the circles of chemistry for a long time, reasons for adopting chemstatistics are given, which is defined as the science of gathering or generating, describing, summarizing and interpreting the data concerned to acquire new chemical knowledge or information. the fact that many traditional statistical methods, such as significance tests, analysis of variance, regression and correlation, and some others not usually considered statistical, such as model building, monte carlo method, fourier transformation, artificial nerval networks and pattern recognition, each contains one or more of the five connotations of statistics is expounded. the regular pattern that a chemstatistician grows up is approached. the urgent task is to include chemstatistics in the undergraduate or graduate curriculum of chemistry specialty. the goal of the project is to nurture chemists who know statistics

    文摘:本文追溯了統計學發展、建立中的大事,陳述了它的定義及其化學分支發展、建立的梗概;鑒于化學界對該新興化學分支學科的名稱長期存在爭議,提出了以化學統計學而不以化學計量學為該學科名稱的理由,把化學統計學定義為一個研究有關數據的收集或產生、描述、分析、綜合和解釋,以獲得新化學知識或信息的學科;闡明了許多公認屬于統計學的方法,如顯著性檢驗、方差分析、回歸和相關,以及一些尚未認定屬于統計學的方法,如模型建立、蒙特卡羅方法、傅立葉變換和人工神經網路,都含有統計學5個內涵中的一個或多個;探討了化學統計學家成長的模式,認為當務之急是把化學統計學納入化學專業的教學計劃,以培養懂統計學的化學家。
  4. Then fourier transformation is employed to solve equations of motion of the rings, bulkheads, stringers and fluid respectively, with their reactions ( moments ) expanded by the shell ' s in - vacuo modes. by means of continuity conditions on the interfaces between the shell and the stiffeners as well as the fluid, and inverse fourier transformation, the modal reactions ( moments ) are finally expressed by the shell ' s modal velocities

    然後用fourier變換分別求解環肋、艙壁、縱骨和流場的運動方程,將它們對殼體的作用力(力矩)用殼體周向模態展開,利用它們與殼體在連接處位移連續條件以及fourier逆變換得到用殼體速度表示的模態相互作用力(力矩) 。
  5. By performing fourier transformation, the relationship between the turbulent intensity of the particle and that of the carrier fluid was obtained which makes clear that particle size, specific gravity, velocity gradient, and the characteristic frequency of energy - containing eddies are four basic influencing parameters. it is proven theoretically that under certain conditions, the stream - wise and transverse particle turbulent intensities exceed those of the carrier fluid. based on the equations of two - phase flow, the presence of fine sediment suspension is shown to attenuate the turbulent intensity of the water

    通過對細小顆粒在剪切流場中運動方程的fourier分析,得到了顆粒脈動強度和流體脈動強度之間的定量關系,表明顆粒粒徑、顆粒密度、流速梯度以及紊動場含能旋渦的特徵頻率是影響顆粒脈動強度的主要因素,首次從理論上證明了在一定條件下,顆粒在縱、垂向的脈動強度均會超過相應的流體脈動強度,為已有的實測資料提供了合理的解釋。
  6. In this thesis, summarized the basic theories of fourier transformation and the fast fourier transformation that are generally adopted to detect and analyze the electric power harmonic in the electric power supply system. at the same time, summarized the even sample principle, the phenomenon of frequency mix, the window functions and the frequency leaking as so on, those are closely - related to sample from figure signal

    簡要闡述了電力系統諧波檢測分析所普遍採用的傅利葉變換和快速傅利葉變換的基本理論以及與數字信號采樣密切相關的均勻抽樣定理、頻譜混疊現象、窗函數和頻譜泄漏等的基本理論。
  7. Summarized no - line loads and the present situations of the electric power harmonic pollution in the guangyuan district ' s electric power supply system ; explained the theories of fourier transformation and the fast fourier transformation those are widely adopted by majority scholars to examine and analyze the electric power harmonic in the electric power supply system. summarized the principle of even sample, the frequency mix phenomenon, the window functions and the frequency leaking as so on, those are closely - related to the figure signal

    簡要闡述了電力系統諧波檢測分析所普遍採用的傅利葉變換和快速傅利葉變換的基本理論,簡要闡明了與數字信號采樣密切相關的均勻抽樣定理、頻譜混疊現象、窗函數和頻譜泄漏等的基本理論,同時闡述了電力系統的諧波檢測與分析的相關理論基礎知識。
  8. Because massive harmonic interference in the electrical network, it causes signal - sampling to include the very big harmonic in the measurement system, for eliminating measurement result influence by harmonic, the paper has an in - depth study of fourier transformation harmonics analysis measurement principle, analysis the forming reasons of frequency spectrum leakage and railing effect during measurement, achieves phase locked loop and frequency multiplier technique to realize integer - period synchronous sampling and eliminate impact of frequency spectrum leakage and railing effect in the result of measurement, and investigates in depth theory on phase locked loop and frequency multiplier technique, gives the method of realizing phase locked loop and frequency multiplier technique

    由於電網中存在大量的諧波干擾,導致測量系統中取樣信號也含有很大的諧波,為了消除諧波對測量結果的影響,論文深入研究了傅立葉變換諧波分析法的測量原理,分析了測量中頻譜泄漏和柵欄效應形成的原因,提出了採用鎖相環倍頻技術實現信號的整周期同步采樣,消除頻譜泄漏和柵欄效應對測量結果的影響,並對鎖相環倍頻技術的理論進行了深入研究,給出鎖相環倍頻技術的實現方法。
  9. Then we obtain the height and current of a storm moving along the seacoast at the continental shelf by using fourier transformation

    運用fourier變換及其反演變換求出了風暴潮潮高和風暴潮流的解析表達式。
  10. In chapter 2, the first and the second section give explicit explanations of how to use split - step fourier transformation ( ssft ) algorithm and finite - difference methods to solve nonlinear equation. a code table, in which a list of normalized transmission formula is included, is given to facilitate programming

    第二章,前兩節詳細介紹了如何用分步傅里葉變換演算法和有限差分法實際求解非線性方程,並給出了求解光束、脈沖及脈沖光束的歸一化方程編碼表,供編程參考。
  11. Pulse step return loss from measurement in the frequency domain using the inverse discrete fourier transformation

    反向不連續傅里葉傳輸的頻率區域內脈沖分步回損測量
  12. In section 4, by making use of the fourier transformation for spatial variables and starting from the nonparaxial propagating equation of ultrashort pulsed beam in temporal frequency domain, the nonparaxial solution basing on the paraxial propagating solution was derived, which come to exact solution by iterative of the paraxial integral solution

    在第四節里,通過採用空間變量的傅立葉變換和利用時間頻率域下的非傍軸傳輸方程,我們得出了超短脈沖光束傳輸的非傍軸的修正方法。
  13. At the doppler centroid aspect, this paper make use of maximum value method ; energy method and autocorrelation function method to estimate doppler centroid. at the doppler frequency aspect, this paper make use of image offset method ; time - frequency method ; minimum entropy and fractional fourier transformation method to estimate doppler frequency rate

    在多普勒參數估計中,採用了最大值法、能量法和自相關函數法進行多普勒中心頻率估計;採用了圖像偏移法、時頻分析法、最小熵法和分數階傅里葉變換法進行多普勒調頻斜率估計。
  14. The composites with different compatibilizers and nano - sio2 content were characterized by means of mechanical testing, differential scanning calorimetry ( dsc ), x - ray diffraction ( xrd ), fourier transformation infra - red spectroscopy ( ft - ir ), transmission electron microscope ( tem ), scanning electron microscope ( sem ), etc. the relation between the structure and property of the composites was discussed in this thesis

    研究了不同增容劑、納米sio _ 2含量對復合材料的沖擊強度、拉伸強度等力學性能;並利用差熱掃描量熱分析( dsc ) 、 x射線衍射譜( xrd ) 、紅外吸收光譜( ir ) 、掃描電鏡( sem )等分析,討論了復合材料結構與性能的關系。
  15. A fast fourier transformation based second order reliability method

    基於傅立葉變換的變元可分離核函數的確定方法
  16. 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。
  17. Firstly, in the paper a family of integral solution representing ultrashort pulsed beam propagating in free space have been studied by using the co - moving frame coordinates and the fourier transformation for time variable in terms of well - known paraxial approximation. and the pulsed gaussian - like beam solution can be obtained as a especial solution of the integral solution, where including the pulsed gaussian beam

    首先利用傅立葉變換和惠更斯-菲涅爾衍射積分公式,我們給出了傍軸標量場近似下超短脈沖光束傳輸的基本積分解,並進一步得到了用卷積形式表示的脈沖類gauss光束解( pulsedgaussian - likebeam )的普遍形式解。
  18. This bias mainly come from the un - uniform characteristics of the system and the couplings between the receiving channels. if we use fourier transformation to retrieve the image, the errors introduced by this bias will not be represented

    如果使用理想的傅立葉方法反演亮溫圖像將反映不出系統的不理想因素,而且因為這些誤差對于可視度函數值的影響不同,一一剔除是極其困難的。
  19. 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。
  20. The submarine structure is simplified to single or double infinite cylindrical shell stiffened with rings, bulkheads and stringers, focusing on underwater sound radiation from the single shell. the shell motion is described by donnell ' s theory including excitation forces and reactions of rings, bulkheads, stringers and fluid, which leads to the fluid - structure coupling vibration equation. expressing displacements by velocities, applying modal expansion circumferentially and fourier transformation longitudinally result in the shell ' s modal equations of motion

    殼體的運動方程採用較為簡單的donnell理論描述,運動方程中包括了激勵力、加筋結構(環肋、艙壁和縱骨)和流場對殼體的作用力,從而組成流場-結構的耦合振動方程,並進一步將方程中的位移用速度表示,然後沿軸線方向進行fourier變換,將速度和各項荷載沿圓周方向進行模態展開,得到了殼體振動的模態運動方程。
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