特征参数

Based on the idea of the structure parametric design method, the parametric finite element model of drill chuck with complicated spiral surface character was established.'The related key technologies of drill chuck's strength analysis were discussed and solved, such as the contact analysis parameters selection, the boundary conditions and the load processing, ANSYS command一string building and so on.

本文采用结构参数化设计方法建立了含有复杂螺旋曲面特征的钻夹头参数化有限元模型；探讨和解决了钻夹头夹紧强度分析中夹爪与螺母接触分析参数的选择、约束边界和载荷处理、分析流程文件创建等关键技术问题。

The mechanical parameters in the model are treated as random variables and it is then resolved with Taylor extension stochastic finite element method, The distribution characteristics of the pore pressure, the effective stress and the displacement are researched by treating the mechanical parameters of the rock as random variables. The sensitivities of the pore pressure, the effective stress and the displacement to the random mechanical parameters are also analyzed.

视模型中的参数为随机变量，采用Taylor展开随机有限元法对该模型进行数值模拟，研究参数具有随机性情况下耦合场中孔隙压力、有效应力，位移等场变量的随机分布特征及孔隙压力、位移等场变量对参数的灵敏度。

In order to avoid using the formant transitions of each phoneme as the training parameters, we propose a procedure to select the steady-state formant features for each phoneme. 2. Accent analysis for Mandarin Chinese based on formant frequencies is presented in this paper.

该方法能够通过选取该音素中间的稳定段参数作为对应音素的参数的手段，避免以往方法中不考虑协同发音对声学特征的影响，而将音素过渡段的参数进行模型训练的问题。

They are as following: to establish the selection method of the slaving designed quality functions according to the interrelationship among designed quality functions; to construct the measurement functions of the optimality robustness with the hypersurface characteristics around the current iterative point of designed quality functions.

具体地，根据设计性能函数之间相互关系给出了处于支配地位设计性能函数的选择方法；利用设计性能目标函数在当前迭代点附近的超曲面特征，构造设计性能目标函数的最优性健壮度量函数；按照系统有序化设计模型的最优解应同时具有可行性健壮与最优性健壮的要求，通过计算设计性能目标函数与约束函数对设计变量的波动与非设计参数的波动的一阶敏度来确定系统有序化设计模型中的健壮参数；并以此为基础建立了进一步考虑非设计参数波动对设计变量波动有影响的后健壮分析方法。

This characteristic could be qualitatively explained as interference between σ amplitude and π amplitude of electrons final wavefunction. It also depends on the impact parameters: the π amplitude contribution is dominant at small impact parameters, which leads to a symmetric velocity distribution around the internuclear axis. However, At large impact parameters the σ amplitude contribution increases relatively, resulting into a asymmetric electrons velocity distribution around the internuclear axis.

出射电子的上述分布特征可由出射电子波函数σ振幅和π振幅的干涉进行定性解释，σ振幅和π振幅对出射电子波函数的贡献与碰撞参数相关，在小碰撞参数下，π振幅的贡献更加明显；而在大碰撞参数下，σ振幅的贡献更加显著。

In order to reduce calculation error, the frequency distribution of average values is used to compute the mixed distribution's digital features of each component distribution, thereinto, the number of the component distribution is determined by AIC, choose the number that meets the minimum value of AIC as the component number of mixed distribution, and the other parameters are estimated by EM algorithm; Secondly, because each component distribution is corresponding to a kind of major gene genotype, according to the values of the average and variance of the each component distribution, we can use the limit error of the normal distribution to plot each individual into the correspondent component distribution, namely into correspondent major gene genotype. Then we regard each major gene genotype as a treatment level of one-way analysis of variances, and the one-way multivariate analysis of variance is carried out to calculate the covariance matrix of major gene effect, covariance matrix of polygene effect, covariance matrix of environment effect and so on; At last, combining the weights of the each component distribution of mixed distribution, we can calculate the variance of major gene effect, the variance of polygene effect, environmental variance and the genetic gain of the quantitative trait.

为减小计算误差，本研究采用均值的频数分布来计算各成分分布的数字特征，其中成分分布个数根据AIC准则，选择使AIC值达到最小的成分分布个数作为混合分布的成分分布数，分布中其它参数的确定利用EM算法来估计；其次，每个成分分布对应一种主基因基因型，根据各个成分分布的均值和方差，利用正态分布的极限误差将每个个体划分到相应的成分分布中，即相应的主基因基因型中，将每种主基因型作为单因素方差分析的一个处理水平，对其进行单因素的多元方差分析，分别计算主基因效应协方差阵、多基因效应协方差阵、环境协方差阵等参数；最后结合混合分布中各成分分布的权重即各主基因基因型的分离比例，计算主基因效应方差，多基因效应方差和环境方差，以及遗传力等参数，进而计算该数量性状的遗传进展。

The experiment results prove that the way with regularization technology is better than the way without regularization technology. In order to overcome the limitation of the regularization method, chapter 6 builds an irregular MRF model suitable for the motion estimation of feature point based on MAP-MRF frame. The energy function, which can reflect the joint probability distribution of motion parameters and the constraints relation of local 3D motion parameters, is established in irregular MRF.

为了解决正则化方法只能分析非刚体局部三维运动的缺点，第6章在基于MAP-MRF的分析框架中建立了与特征点运动估计相对应的非规则MRF模型，构造了非规则MRF模型中反映非刚体局部三维运动参数之间约束关系和运动参数联合概率分布的能量函数，通过能量函数最小化估计运动参数。

The obtained QSRRs can not only be used to predict retentions for structurally related compounds, but also be used to elucidate the molecular mechanism of separation for RP-HPLC. In addition, the obtained structural descriptors can be readily used in the studies of quantitative structure-activity relationships .

通过结构与色谱保留间关系的研究，我们还发现分子连接性指数，溶剂化参数及量化参数可以有效地表征所研究化合物的结构特征，这些参数可以进一步应用于定量结构-活性相关的研究中。

With regard to CAD modeling in reverse engineering, some key techniques, including feature extraction from point cloud and parametric representation, are studied.

本文针对反求工程CAD建模路线：从点云提取特征曲面，再进行曲面参数化CAD造型过程中非常关键的步骤——特征提取进行了深入研究，着重研究了二次曲面特征的提取，并对点云中的全局特征约束优化技术进行了有益的探索。

The feature points from two images were extracted by Harris corner detector, then the corresponding feature point pairs were got by the cross-correlation of the gray scale around the feature points, and the mismatched pairs were eliminated based on the Eulerian distance of the transformation parameter vector.

提出了一种基于特征点的图像拼接算法，首先利用Harris角点检测提取两幅图像中的特征点，用特征点邻域灰度相关性将特征点进行匹配，并在此基础上根据变换参数向量的欧式距离对误匹配进行剔除，进而实现图像拼接。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。