approximation model 中文意思是什麼

approximation model 解釋
近似模式
  • approximation : n. 1. 接近；近似。2. 【數學】近似值。3. 概算，略計。
  • model : n 1 模型，雛型；原型；設計圖；模範；（畫家、雕刻家的）模特兒；樣板。2 典型，模範。3 （女服裝店僱...
  1. The jellium model in a certain approximation leads to the equation.

    凝膠模型在某種近似下導致下列方程。
  2. There has been many papers to discuss the in - medium quark and gluon condensates in nuclear matter which use the models with su ( 2 ) l su ( 2 ) r sym - metry. now, we make use of the chiral model su ( 3 ) l su ( 3 ) n including the baryon octet to discuss the quark condensate < qq > in strange matter, where q is an up or down quark field. on the one hand, from the experimetal data, it is found that < qq > vac = - ( 225 25mev ) 3, on the other hand, with the hellmann - feynman theorem, quark condensate can be evaluated on the hadronic level. in this paper, we will investigate the quark condensate in strange matter with the chiral symmetry su ( 3 ) l x su ( 3 ) rspontaneous breaking lagrangian to obtain the variation of the quark condensate in the strange matter when the baryon number change. it can be applied to understand the neutron stars when the neutron star are considered to be constructed by the strange matter. because nertron stars are homogeneous and at very low temperature, we will use the mean - field approximation and zero temperature throughout this paper

    鑒于已有大量文獻討論了核物質中的夸克凝聚，本文將討論在奇異物質中的夸克凝聚。而在介質中的夸克凝聚的基本公式可由hellmann - feynman理論導出，所以運用手征對稱自發破缺拉氏量以及平均場近似，我們就可以討論在奇異物質中的夸克凝聚，由所計算的結果表明： （ 1 ）奇異物質中的夸克凝聚隨奇異物質密度的增大而單調減小。 （ 2 ） -凝聚的出現對衰減率有影響。
  3. The approximation analysis result of band dipole model is obtained on the basis of the theory of mfl. the electromagnetic distribution feature of the defect in the steel panel is studied by means of simulation. the leakage magnetic distribution of the two defects and four defects plural and the defects in the column differently in the width are also assayed. conclusions that factors affecting flaw magnetic leakage to the panel also affect the column and magnetic leakage bx should be the feature of the flaw identification to several flaws are drawn

    在對漏磁檢測原理進行詳細介紹的基礎上，得出了帶偶極子模型的近似解析解，並以有限元數值模擬分析為主要手段，以鋼板上缺陷為對象，分析了各因素對缺陷漏磁場產生影響的不同規律，同時模擬分析了板上平行的兩條裂紋，四條裂紋以及柱體上寬度不同時的裂紋的漏磁場分佈特徵，得出結論:影響板上缺陷漏磁場的諸因素會對柱體上缺陷漏磁場產生同樣的影響;對于多條裂紋，宜用漏磁分量bx作為缺陷識別的特徵量。
  4. Collisonal quantum interference ( cqi ) was observed in the intramolecular rotational energy transfer in the experiment of the static cell, and the integral interference angles were measured. to observe more precise information, the experiment in the molecular beam should be taken, from which the differential interference angle can be obtained precisely. in this paper, the theoretical model of cqi is described in an atom - diatom system in the condition of the molecular beam, based on the first - born approximation of time dependent perturbation theory, taking into accounts the anisotropic lennard - jones interaction potentials. the method of observing and measuring correctly the differential interference angle is presented. the changing tendencies of the differential interference angle with the impact parameter, velocity, and et al. are discussed

    分子內部轉動傳能的靜態池實驗觀察到了碰撞量子干涉效應（ cqi ） ，並且測得積分干涉角，為了獲得更加精確的分子內部轉動傳能的碰撞量子干涉效應信息，實驗就必須要採用分子束實驗進行.本文理論上採用各項異性相互作用勢，應用含時微擾理論的一級波恩近似，假想在分子束實驗的條件下，建立在原子-雙原子分子體系中碰撞量子干涉的理論模型.理論上推導出微分干涉角具體表達式，通過計算定性地討論了微分干涉角隨著碰撞參數、速率等的變化趨勢，同時初步探討了實驗的正確觀測途徑，得出了採用分子束進行實驗觀測的實驗方法，為進一步進行分子束實驗提供了理論基礎，對實驗的進行起到了一定的借鑒作用
  5. The work of the paper mainly includes : ( 1 ) present a model for measuring the similarity between two hydrological time series. in this model, we adopt an intuitive dimensionality reduction technique for hydrological time series which is called piecewise average approximation ( paa )

    主要工作包括： （ 1 ）提出了適合水文時間序列數據特點的相似性模型，採用簡單直觀的等時間間隔序列分段平均值技術（ paa ）作為水文時間序列降維方法。
  6. For micro - cavity semiconductor laser, station model is proposed in this paper and its steady - state and instantaneous characteristics when the coupling efficiency of spontaneous emission into a lasing mode is equal to 1 are analysised. for current noise, sp noise, noise, p noise, as well as current modulation, sp modulation, modulation and p modulation, using small - signal approximation, we derive the laser ' s corresponding transfer functions. and we calculate their signal - to - noise ratio ( snr ) gain in various parameters through frequency domain analysis in the premiss of large input snr

    本文對于微腔半導體激光器，提出站模型，能夠較直觀簡潔地分析微腔半導體激光器的穩態和瞬態特性，利用此模型對具有重要實用價值的= 1的微腔半導體激光器進行了討論；對于電流i噪聲、自發發射壽命_ （ sp ）噪聲、自發發射因子噪聲、光子壽命_ p噪聲，以及電流調制、 _ （ sp ）調制、調制、 _ p調制，在小信號近似下，得到了相應的激光器的傳遞函數；在大信噪比的前提下，對激光器進行了頻域分析，分別計算了它們在不同參數下的信噪比增益，分析了其抗噪聲性能。
  7. We also give the properties and the convergence of the two models. in the aspect of the fractal approximation of surfaces. we propose the improved quadrangular projected ifs ( qpifs ) model and quadrangular rational projected ifs ( qrpifs ) model

    在曲面的分形逼近方面，首先給出了改進后的四邊域曲面的投影迭代函數系統模型，然後給出了四邊域曲面的有理投影迭代函數系統模型。
  8. The opacity of element is calculated with a bsa ( band smear approximation ) theory on the basis of hydrogen - like screen average atom model

    在此基礎上，用能帶抹平近似方法計算元素的不透明度。
  9. The dissertation proposes originally the idea of decomposing the time - variant load to solve this problem. first, the time - variant load is decomposed into the time - variant load characteristic and the time - variant load model due to the modeling method. second, the multi - curve approximation method is proposed to identify the load parameters, which to a great extent, reduces the effects on the time - variation of the load model from modeling method

    針對負荷的時變性，論文首次提出了將負荷時變性分解的思想，首先將負荷的時變性分解為負荷特性的時變性和由建模方法引起的負荷模型的時變性，然後提出了多曲線擬合參數辨識方法，很大程度上消除了建模方法引起的負荷模型的時變性。
  10. The equation including the nonlinear dispersion, i. e. the modified nonlinear schrodinger ( mnls ) equation, is a better model. in this thesis, we take mnls solitons as a model for femtosecond soltions. then based on the recently developed direct perturbation theory for perturbed mnls equation, we study the raman self - frequency shift of femtosecond solitons and its suppression by the means of frequency filters. for this purpose, first, we define the physical parameters of mnls solitons ; next, through the direct perturbation theory for perturbed mnls equation, under adiabatic approximation, we obtain the evolving parameters of mnls soliton on our questions and then choose the parameters of frequency filters based on it ; at last, we directly numerically simulated our questions by split - step fourier ( ssf ) method after improving the arithmetic of the differentiation of the nonlinear item for satisfying mnls equation

    本論文以mnls孤子作為光纖飛秒孤子的模型，通過新近建立的mnls孤子直接微擾理論，研究光纖中由拉曼效應引起的飛秒孤子在傳輸中的自頻移，以及通過頻率濾波對自頻移的抑制。為此，首先給出描述mnls孤子的各物理量，然後用mnls孤子直接微擾理論，解析地得到這些問題絕熱近似下的孤子參數演化，並由此選擇頻率濾波的參數，最後用分步傅里葉方法，在對非線性項微商的演算法做出了適合於mnls孤子的改善後，對拉曼效應及頻率濾波進行了直接數值模擬，其中頻率濾波參數用微擾理論確定。
  11. This article describes the development process of surrogate models and introduces some experiment design methods and approximation approaches that can be used for a mdo surrogate model, they are full factorial experiment design, orthogonal experiment design, uniform experiment design, central - composite experiment design, and polynomial response surface method, kriging method, radial basis function method and artificial neural network

    為此本文中分別介紹了正交試驗，均勻試驗以及中心復合試驗等幾種試驗設計方法，以及多項式響應面， kriging ，和徑向基函數等幾種數學近似方法。並且通過構造描述機翼展向升力分佈的代理模型，對上述幾種方法作了對比分析。
  12. On the other hand, the electric field and intensity distributions of the he11 mode in the hollow fiber are calculated by using the exact solutions of maxwell equations based on the vector model, and the diffracted near - and far - field distributions of the he11 - mode output beam under the fresnel approximation are studies. we derive an analytical expression on the far - field distribution of the he n - mode output beam in free space and discuss its applicable condition. we also analyze and compare the differences between the he11 - and lp01 - mode output beams, and find that the near - field distribution of the lpoi - mode output beam is a gaussian - like one, but the near - field distribution of the he11 - mode output beam is a doughnut - like one, whereas the far - field distribution of both the lp01 - and he11 - mode output beams are a doughnut one

    此外，我們把中空光纖中lp _ （ 01 ）模（標量模型）和he _ （ 11 ）模（矢量模型）的場分佈以及它們各自的輸出光束的近場與遠場分佈進行了比較，發現兩種模式的輸出光束在近場分佈有很大的區別， lp _ （ 01 ）模輸出光束在近場是一個高斯分佈，而he _ （ 11 ）模輸出光束在近場是一個中空光束，在遠場兩種模式的輸出光束分佈是基本一致的，這正是由於在中空光纖中採用了弱波導近似以後所引起的誤差。
  13. The thesis also discusses the thermal blooming and physical of the heat halo produced by intense laser. the thesis emphasizes on otf and psf of atmospheric turbulence. taking three screen systems as the example, we get the ideal approximation model, especially the short - exposure otf

    並介紹了強激光產生熱暈的理論模型及其物理特性機理，重點介紹湍流大氣的otf和psf ，以三種屏系統為例，得到湍流大氣的理想近似模型，特別是短曝光otf 。
  14. Firstly, samples are determined by experimental design methods and size optimization of the structures corresponding to the samples is executed with nastran. secondly, an approximation model ( surrogate model ) based on the samples is derived using kriging method. thirdly, the optimal locations of structural elements are found by genetic algorithms ( ga ) because genetic algorithms can find global optimal solutions of surrogate model easily

    基本思路是利用試驗設計法選取樣本點，並對樣本點對應的結構進行尺寸優化，然後根據樣本點和優化結果建立代理模型，再利用遺傳演算法求出設計變量最優解，進而得到結構最優解。
  15. An optimal hankel norm approximation model reduction method is used to reduce the equations of motion to lower order size. it is shown that the method is steady, efficient by numerical emulating. firstly, the influence of viscoelastic layer thickness and material properties, piezoelectric actuator layers thickness on the vibration suppression are investigated

    採用最優hankel最小階逼近降階法對主被動混合阻尼結構的控制狀態方程進行降階，以附加主動約束阻尼層的梁結構為例，進行了數值模擬，結果表明：該方法是一種穩定的、高效的、魯棒性很好的降階方法。
  16. In the aerodynamic optimization design of turbomachine, the approximation model methods enable to balance the computational cost and accuracy, whose successful applications in centrifugal compressor impeller, diffuser, and mixed - flow pump impeller designs are introduced to show a wide engineering foreground

    基於統計學理論提出的近似模型方法有效地平衡了基於計算流體動力學分析的葉輪機械氣動優化設計中計算成本和計算精度這一對矛盾，在離心壓氣機葉片擴壓器、葉輪和混流泵葉輪設計等問題中得到了成功應用，展示了廣闊的工程應用前景。
  17. Especially, the approximation model methods can be applied to the aerodynamic optimization design instead of the time - consuming computational fluid dynamics ( cfd ) analysis to shorten the design process and reduce the computational cost

    在氣動優化設計過程中，用該模型取代耗時的高精度的計算流體動力學分析，可以加速設計過程，降低設計成本。
  18. The thesis studies the generalized rough set models and proposes a multi - level rough set approximation model cbm - rs based on a covering of the universe

    作者研究了粗糙集擴展理論，提出了一種多層粗糙集模型cbm - rs 。該模型是一種基於覆蓋的擴展的多層粗糙集模型。
  19. The shifts of absorption edge of nanocrystsls compared with that of bulk have been calculated by means of effect - mass approximation model. the calculation and experimental results looked almost same

    用有效質量近似模型（ ema ）計算了半導體納米晶體的吸收邊相對體材料的移動，並將理論結果和實驗結果進行了比較，兩者相符較好。
  20. To reduce huge computation of the traditional stochastic optimization methods for engineering optimization, approximation model methods with acceptable accuracy for engineering design are developed based on the statistical theory

    摘要針對在工程中完全採用隨機類優化方法尋優時計算量過大的問題，應用統計學的方法發展了計算量小、在一定程度上可以保證設計準確性的近似模型方法。
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