helmholtz theory 中文意思是什麼
helmholtz theory
解釋
共振學說-
A new coupled - mode theory based on scalar modes is presented for the anisotropic waveguide with random disturbance via helmholtz equation and a modified dielectric tensor
摘要從亥姆霍茲方程出發，得到了各向異性光波導在弱導近似下的耦合模理論。 -
First, in virtual of identification of flaws is a typical of in - verse problems, proceeding from time - harmonic electromagnetic maxwell ' s equa - tion and helmholtz equation, the uniqueness and existence of direct scattering problems including the numerical algorithms of diverse of boundary conditions is given. second, the uniqueness and existence of inverse scattering problems and the theory of ill - posed integral equation are briefly looked back upon. finally, indicator function method for boundary identification is set up under all kinds of boundary conditions for inverse scattering of homogenous and inhomogenous objects, meanwhile, the proof of possibility for near - field measurements and nu - merical simulation are given
由於缺陷的識別是一類典型的反問題，因而首先從時諧電磁maxwell方程和helmholz方程出發，具體地闡述了求解正散射問題的有關方法，包括各種（夾雜）邊界條件下的數值解法，就解的存在性唯一性給予了肯定的回答；隨后對逆散射問題的理論作了簡短的回顧，包括解的唯一性以及非線性不適定積分方程的處理等；然後對均勻介質和非均勻介質的逆散射問題建立了在各種邊界條件下的邊界識別的指示函數方法，鑒于近場數據獲得的重要性，對近場測試時邊界識別的方法給予了相應的證明，並且實現了數值模擬。 -
Base on helmholtz integral equation, the incoherent scattering of plane wave from rough cone - shaped surface is derived with the far field theory and stationary phase method. and the incoherent scattering of plane wave from rough conical surface is also derived with shadowing function when the the radius of principal
最後計算並分析了入射光為= 0 . 48 m時，粗糙錐面的平面波散射特性，考察了入射波和散射波的幾何關系，偏振態以及粗糙面統計參量等對散射強度的影響。 -
In this dissertation, the numerical computation for the acoustic radiation problem ( arp ) is studied deeply and systematically in the theory, method and the application technique, based on analyzing the situation of the home and abroad on the numerical computation for the acoustic radiation problem. the calculation formulas of the boundary element method ( bem ) for the exterior acoustic radiation problem in the full - space and half - space are deduced, based on the wave propagation theorem ; the arising of the non - unique solutions, which is associated with the application of the boundary integral equation ( bie ) in acoustic radiation problem, is analyzed and proofed ; the improved combined helmholtz integral equation formulation ( ichief ) is presented to overcome the non - uniqueness problem more effectively and reliably ; the determination of the singular integral coefficients on various occasions is analyzed ; the properties and treatments of the singular integrals with different orders axe studied ; the computation program of the cubic spline ichief is developed and its ability to overcome the non - uniqueness problem and feasibility to discrete the surface coarsely with the sufficient calculation precision are examined through examples
第二章在聲波動理論基礎上，詳細地推導出對應于無限域和半無限域的外部振動聲輻射問題的邊界積分方程計算公式；根據fredholm積分理論，對利用邊界積分方程計算振動聲輻射問題過程中解的非唯一性的產生進行了分析和證明；改進了chief法以提高其克服解的非唯一性的有效性和可靠性；對不同條件下奇性系數的計算、強奇性積分的收斂性及其在變量替換時與普通積分的差異性、不同階奇性積分的計算、數值求積分等進行了研究；開發了三次樣條改進chief法計算軟體，並通過算例考核了該方法在特徵波數處克服解的非唯一性的有效性和在保證計算精度的前提下實現剖分粗化以提高計算效率的可行性。 -
Secondly, the helmholtz oscillator was designed. based on the flow network theory, the expression of intrinsic frequency was deduced. the main parameter of helmholtz oscillator was calculated
對于同一結構的helmholtz共振腔，水力參數不同，所產生的自激振蕩脈沖射流的強弱也不相同。 -
First of all, the algorithm base on the boundary problem of helmholtz equation and finite - difference technique, calculate the field in “ cold ” cavity and disperse the helmholtz equation, as a result of the formula : ax = x. secondly, according to the eigenvalue of matrix theory and applied iterative methods, eigenmode adopt a numerical approach which allows the improved chebyshev polynomial iteration which based on the power method to extract the isolated eigenmode in the spectrum. finally, we resolve the problem of compatibility in software and insert the eigenmode module into the chipic which will have the function of eigenmode analysis
具體的說: （ 1 ）首先以電磁理論中的亥姆霍茲方程的邊值問題理論和計算電磁學中的有限差分法為基礎，計算冷腔中的場分佈並離散亥姆霍茲方程，得到標準的本徵值問題: ax = x ; （ 2 ）然後根據矩陣理論中的eigenvalue問題和數值計算中的迭代方法，採用改進后的chebyshev多項式，在power迭代法的基礎上對ax = x進行多項式迭代，實現對頻譜中孤立本徵模的萃取; （ 3 ）最後將用fortran語言編制的eigenmode模塊加入到chipic軟體中，解決了eigenmode模塊與chipic主代碼的兼容問題，從而實現了chipic軟體的模式分析功能。 -
A new approach, the multipole theory ( mt ) method, is briefly described for analysis of waveguide eigenvalue problems. the essential concept is to represent the solution of the waveguide partial differential equation by the generalized mt formula of 2 - d helmholtz equation. the applied rules and the procedure of the mt method are also introduced. by calculating and analyzing some engineering problems, it is shown that the mt method is an effective approach for analysis of waveguide eigenvalue problems
本文利用多極理論分析波導本徵值問題.給出用多極理論分析波導本徵值問題的使用規則和實施方法.實例計算結果表明，用多極理論分析波導本徵值問題，不僅具有較高的計算精度，而且可以很方便地應用於波導工程問題的設計與計算，多極理論是一種有效的波導本徵值分析方法 -
This paper has presented the situation of intake silencer research and application and expounded the intake noise engendering cause and the basic theory on controlling the intake noise. then a research established in the accurate determination of resonance frequencies of different kind of helmholtz resonators is done. according to different assumptions, four kind of mathematical models are established, and the relations between them are discussed
本文介紹了進氣消聲器研究與應用的現狀與發展，闡述了進氣噪聲產生機理及控制的基本理論，研究了helmholtz共振型進氣消聲器的原理，立足於helmholtz共振型進氣消聲器的共振頻率的準確確定，建立了兩類四種共振腔模型，並討論了它們之間的相互推演關系。 -
We regard every layer of grain as a lot of helmholtz resonators in parallel, and regard different layer of grains as the paralleling resonators in series. the grain is a combined resonator in series and parallel. based biot ' s theory of acoustic propagation in porous media this paper applies johnson ' s model to grain media
一定厚度的糧食可看作是一種組合式共振吸聲結構，每層認為由許多個單獨亥姆霍茲共振腔並聯而成，而層與層的共振腔為串聯關系，表現為共振性吸收，出現了共振吸收峰。
分享友人