Chapter 8: We discuss the acceleration of multigrid by Krylov subspace approaches, and recognize the reason for slow convergence of algebraic multigrid methods is that error reduction is significantly less efficient for some very specific error components which may cause a few eigenvalues of the algebraic multigrid iteration matrix to be considerably closer to 1 than all the rest. However, the eigenvectors belonging to the few isolated eigenvalues can be expected to be typically captured after only a few conjugate gradient iterations, which accelerate algebraic multigrid algorithms. Theoretical analysis and numerical results of some practical problems show the iterant recombination accelerates algebraic multigrid convergence.

第八章：先介紹用Krylov子空間迭代法加速一般多重網(wǎng)格方法收斂的基本框架，然后緊緊抓住引起代數(shù)多重網(wǎng)格方法收斂減慢的根本原因往往是誤差減小對(duì)幾個(gè)特別的誤差分量不明顯超级毛片网址在线观看，這導(dǎo)致代數(shù)多重網(wǎng)格方法的迭代矩陣的幾個(gè)特征值接近于1一级黄色AAA性爱片，而共軛梯度方法則能比較典型地捕捉屬于孤立特征值的特征向量，從而推導(dǎo)出有效的共軛梯度加速算法和程序?qū)崿F(xiàn)国产黄美女视频网站，不僅從一些具體的實(shí)際應(yīng)用例子的數(shù)值結(jié)果去驗(yàn)證迭代復(fù)合加速收斂的效果三级黄片a，而且還從理論上分析了預(yù)處理共軛梯度法加速代數(shù)多重網(wǎng)格法收斂的機(jī)理。

Based on the analysis of kinetical process of CH4 -air oxidation, a numerical modeling of the species concentrations and temperature for CH4 jet diffusion combustion is made using a four-step reduced mechanism and two semi-detailed chemical kinetical reaction mechanismsW mechanism and Y mechansim.

在分析甲烷-空氣氧化反應(yīng)動(dòng)力學(xué)過程的基礎(chǔ)上在线观看韩国免费A∨网站，采用四步簡(jiǎn)化機(jī)理和兩種半詳細(xì)的化學(xué)反應(yīng)動(dòng)力學(xué)機(jī)理-W機(jī)理和Y機(jī)理自拍亚洲国产，對(duì)甲烷射流擴(kuò)散燃燒的組分濃度和溫度進(jìn)行了數(shù)值模擬，計(jì)算結(jié)果與實(shí)驗(yàn)結(jié)果進(jìn)行了對(duì)比分析国产原创激情在线观看网站免费下载。

In order to make Maca be introduced to China, the basicproblems related to introduction and planting such as morphology classification, regionlayout, tissue culture and allelopathy were carried out. And the results were as follows:(1) The numerical Taxonomy of Maca and fifteen plants of Lepidium in China wasinvestigated by cluster analysis and the results showed that the method of numericaltaxonomy could be applied for Lepidium and its results were basically consistent with thatof morphology taxonomy and molecular marker such as Pi intron, ITS and cpDNA.

本文圍繞瑪咖在中國(guó)引種栽培的基礎(chǔ)性和關(guān)鍵性問題一级毛片无码不卡直接观看，進(jìn)行了形態(tài)學(xué)分類、區(qū)域規(guī)劃台湾特级黄片、組織快繁以及克生現(xiàn)象等的研究久艹自拍偷拍，取得以下成果：(1)采用聚類分析，對(duì) 15 種中國(guó)獨(dú)行菜屬植物以及瑪咖進(jìn)行數(shù)量學(xué)分類黄色十黄片，結(jié)論與經(jīng)典形態(tài)學(xué)分類以及用 Pi 內(nèi)含子序列AV天堂永久网、ITS 序列和 cpDNA 序列進(jìn)行分類的結(jié)果基本吻合，瑪咖與家獨(dú)行菜国产精品视频免费视频看看、堿獨(dú)行菜的親緣關(guān)系最近性爱日韩一区，相似系數(shù)分別為 0.839、0.722三级片A片一级毛片视频。

The high frequency combustion instability in liquid rocket engine LRE is analyti cally studied by usin g CFD methods.The comprehensive model and governing equations for numerical simu lation of high frequency combustion instability are presented.The PISO and MacCo rmack algorithms are compared in this study.Both methods can successfully handle combustion instability analysis.

應(yīng)用CFD方法對(duì)液體火箭發(fā)動(dòng)機(jī)中的高頻燃燒不穩(wěn)定性進(jìn)行了分析研究高清无码性爱视频在线观看，建立了液體火箭發(fā)動(dòng)機(jī)不穩(wěn)定燃燒數(shù)值模擬的綜合模型和控制方程，比較了PISO和Ma cCormack兩種算法在线观看黄色视频一站，得出了兩種算法均能成功應(yīng)用于不穩(wěn)定燃燒分析的結(jié)論一级做a爰片久久毛片A片高潮。

Diversity and phylogeny of rhizobia isolated from root nodules of Sesbania cannabina in Jinshajiang arid river valley;2. To study the diversity and phylogeny of rhizobia from Sesbania cannabina in JinShaJiang arid river vally in Sichuan,48 rhizobia was isolated,nodulated,and studied by numerical taxonomy,BOXAIR-PCR,16S rDNA PCR-RFLP,sequences analysis of 16S rDNA and GSⅡ.

從金沙江干熱河谷區(qū)田菁根瘤中分離得到48株根瘤菌，在對(duì)其進(jìn)行回接實(shí)驗(yàn)后日本男人插女人，采用數(shù)值分類日韩精品合集第一页免费观看、BOXAIR-PCR、16S rDNAPCR-RFLP清清草影院欧美日韩、16S rDNA和GSⅡ序列分析方法對(duì)這些菌株進(jìn)行研究日韩网友自拍区在线观看视频网站大全，以揭示在金沙江干熱河谷區(qū)這一特殊地理環(huán)境下田菁根瘤菌的多樣性和系統(tǒng)發(fā)育地位。

Fourth, it conducts the formula deduction, analysis and numerical calculations of the noncollinear quasi-phase matching gains and the output parametric spectrum, which leads to the conclusions that under the same circumstances, the gains of noncollinear interaction will be much less than those of the collinear interaction, and consequently the noncollinear interaction possesses the larger acceptance bandwidths than that of the collinear interaction.

對(duì)非共線準(zhǔn)相位匹配的增益和輸出參量光的允許波長(zhǎng)進(jìn)行了公式推導(dǎo)、分析和計(jì)算手机看A片小视频，得到了允許信號(hào)光波長(zhǎng)的精確公式和關(guān)系曲線日韩一级AV不卡毛片完整版。

The multiresolution time-domain algorithm based on the scaling function of the Daubechies wavelet is introduced, and the perfectly matched layer absorbing boundary condition for the algorithm is deduced. In order to overcome the difficulties due to the nonlocalized property of the MRTD basis functions, the pure scattered-field formulation is adopted. The method presented is applied to the scattering analysis of multiple conducting objects, and the numerical results are compared with those by the traditional finite-difference time-domain method. It is shown that the computational resource is reduced drastically without sacrificing much accuracy.

對(duì)基于Daubechies小波尺度函數(shù)的時(shí)域多分辨分析算法進(jìn)行了詳細(xì)論述，推導(dǎo)了MRTD算法的完全匹配層吸收邊界條件亚洲无码天堂在线，為克服傳統(tǒng)MRTD方法中基函數(shù)存在著非局部性的缺點(diǎn)国产精品网站在线，在源的加入上采用了純散射場(chǎng)方法；并應(yīng)用該算法對(duì)多目標(biāo)的電磁散射特性進(jìn)行了分析亚洲欧美日韩国产综合，數(shù)值結(jié)果表明日韩一级片91插，MRTD算法與傳統(tǒng)的時(shí)域有限差分法結(jié)果相吻合，大大節(jié)約了計(jì)算資源18岁禁止入内网站。

By utilizing the theory of numerical processing, digital frequency spectrum analysis and multi-rate digital signal processing, this paper focuses the research on mechanism of the testing error, the compensation of testing error in the field of sampling technology, nonsynchronous sampling, nonuniformly sampling, and puts forward some new analyzing, compensation and realization methods.

本論文通過運(yùn)用數(shù)值處理日韩福利在线视频免费观看网址、數(shù)字頻譜分析和多抽樣率信號(hào)處理的有關(guān)理論和原理，對(duì)采樣技術(shù)人人操人人人人摸人人干、采樣的非同步方式和采樣的多通道方式中的測(cè)試原理国产VA在线视频观看、測(cè)試誤差產(chǎn)生機(jī)理、測(cè)試誤差補(bǔ)償及其應(yīng)用技術(shù)等主要環(huán)節(jié)進(jìn)行了深入的研究亚洲第一色日韩，提出了一些新的分析與處理方法国产久精品，建立了有關(guān)測(cè)試誤差分析與補(bǔ)償?shù)念A(yù)估理論和實(shí)現(xiàn)方法。

The bifurcation and chaos behavior of impact and rubbing fault rotor system caused by the parameters of nonlinear rigidity, rotor rotating speed, eccentric mass is analyzed, in the numerical value analysis method. The bifurcation diagrams, maximum Lyapunov exponent diagrams, Poincaré maps, phase plane portraits, trajectories of journal center, time-history curve, amplitude spectra diagrams of the rotor motion are used. The convert and evolution course of periodical response, quasi-periodical response, double-periodical bifurcation, chaos of the system response is analyzed.(3). It is deduced that the general differential equation of bending-torsional-pendular coupling vibration about rotor with the gyroscopic moment. On the basis of this equation, the general differential equations of coupled bending, torsional and pendular nonlinear vibration about rotor with unbalance character and rubbing character are deduced.

2建立了具有非線性剛度的轉(zhuǎn)子系統(tǒng)在非穩(wěn)態(tài)非線性油膜力作用下的徑向碰摩動(dòng)力學(xué)微分方程人人操人人操人人操人人操人人人操，并應(yīng)用含高階余項(xiàng)的非線性動(dòng)力方程的線性化數(shù)值法研究了此類系統(tǒng)響應(yīng)的復(fù)雜動(dòng)力學(xué)行為少妇无码大屁股视频XXXX，利用轉(zhuǎn)子響應(yīng)的分岔圖、最大Lyapunov指數(shù)曲線一级牧交视频播放在线观看、Poincaré截面映射2020国产精品永久在线、時(shí)域波形、相軌線黄色电影久久久、軸心軌跡欧美日韩亚洲图片、幅值譜等圖形分析了系統(tǒng)響應(yīng)的周期運(yùn)動(dòng)、擬周期運(yùn)動(dòng)四川美女大白屁股黄毛片观看、倍周期分岔、混沌等運(yùn)動(dòng)形式的轉(zhuǎn)化與演變過程天天久久国产精品电影网，重點(diǎn)研究了非線性剛度黄色网站在伦看、轉(zhuǎn)子轉(zhuǎn)速、偏心質(zhì)量等系統(tǒng)參數(shù)對(duì)碰摩故障轉(zhuǎn)子系統(tǒng)的分岔和混沌行為的影響a片一及毛片手机在线免费观看网络。

This method can make sure the structure radiant sound status in total noise and the detail phonate part quickly and correctly.(3) Study on the control mechanism of structure noise radiated from rotary machines, we build a common model of rotary machine structure noise analysis relied on the general characters of rotary machines. Based on this model, we analyzed various influence factors to structure radiant noise using the union of revolution and numerical calculation method. We found that the joint stiffness between the rotor and the frame is the most sensitive parameter of structure radiant noise by calculating and analyzing.

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