查询词典 gradient change

D resistivity forward modeling ; Finite-element ; Secondary potential ; Symmetric successive overrelaxation ; Conjugate gradient.

电阻率三维正演；有限元；异常电位；对称超松弛；共轭梯度

Firstly, the three-dimension boundary question and its corresponding variation question concerning the point-source electrical field on a 3-D structure are presented. Secondly, the finite element method is used to solve the variational equation. The study area is divided into many tetrahedral elements. Then, we interpolate with a tri-linear function in each element. So, the variational equation is converted into a linear equation system. Finally, taking into account saving of time, we make use of symmetric successive overrelaxation preconditioned conjugate gradient algorithm to solve large linear system, and obtain the potential value of each node, resulting in the calculation of the apparent resistivity values on the ground surface.

首先给出了三维构造中点源电场的边值问题以及相应的变分问题；然后利用有限单元法求解变分问题，采用四面体单元对研究区域进行剖分，在单元中进行三线性函数插值，将变分方程化为线性代数方程组；最后，考虑到节约计算时间，利用对称超松弛预条件共轭梯度迭代算法求解大型线性方程组，得到了各节点的电位值，进而计算出地表的视电阻率。

In this study, symmetric successive overrelaxation preconditioned conjugate gradient algorithm is used to solve large linear system derived from 3-D finite-element resistivity forward modeling. Using row-indexed sparse storage mode to store coefficient matrix, the algorithm converges much quickly and requires much less storage of computer.

引入对称超松弛预条件共轭梯度迭代算法求解电阻率三维有限元计算形成的大型线性方程组，并有机结合系数矩阵的稀疏存储模式，使得三维有限元正演计算的速度大大提高而内存需求则大大减少。

Methods Human pancreas tissue was digested with collagenase P using a semi-automated pancreas-digestion system followed by purification in a HCA-Ficoll continuous gradient using Cobe2991 cell separator.

方法使用自制的半自动人胰腺消化分离装置及胶原酶P进行人胰腺的消化分离，用COBE2991细胞分离机及HCA-Ficoll纯化人胰岛细胞。

In the paint program, paint over the particles so they get covered with a gradient like this, and save the image.

3.9 在绘画程序中，描绘整个粒子，这样他们将被一种渐变色覆盖，然后保存这张图片。

It is shown that the pressure distribution is a piecewise parabolic curve, and the pressure gradient can be discontinuous at the border of the slip and no-slip regions.

结果显示压力分布为分段光滑的抛物线，在滑移／非滑移边界，存在不连续的压力梯度。

Acquisition of high-quality chromosome suspension: The chromosome suspension released from homogenization suited for flow karyotypic analysis and sorting after fixed in 2% paraformaldehyde for 20 minutes and purified through 10% and 30% sucrose concentration gradient.

高质量染色体悬液制备结果：同步化的根尖细胞经2%多聚甲醛固定20 min，机械匀浆释放染色体并结合10%及30%蔗糖浓度梯度纯化释放的染色体悬液。

The parametric optimization model is established on the basis of explicit least square error, and the parameters of digital points are optimized by subspace interior reflective conjugate gradient method.

建立了基于显式的最小二乘重构误差的参数优化模型，运用子空间共轭梯度内部反射牛顿优化技术实现了大规模数据点的参数优化。

Fuzzy logic is used to get the membership function with the local characteristics of the gradient and phase angle.

为解决传统图像插值算法存在的边缘模糊和边缘锯齿，提出了一种基于像素点模糊隶属度的图像自适应插值方法。

The resolution and renaturation efficiency of lysozyme were found to be independent of the flow rate and gradient time when the volume of mobile phase was kept a constant.

在计量置换模型的基础上首次提出了流动相用量估算公式，用实验对其进行了检验，并得出在保持流动相用量不变的条件下，改变流速和梯度时间对分离度和变性蛋白的复性效率影响不大的结论。

Researches reveal that students who suffer from corporal punishment tend to resort to violence in their future life.

研究表明遭受过肉体惩罚的孩子倾向于在他们今后的人生中使用暴力。

Total sugar of sarcocarp and chlorophyll of pericarp increased firstly, and then decreased afterward along with altitude; Titratable acidity, ascorbicacid and anthocyanin of pericarp were increased along with altitude; The content of protein increased firstly and decreased afterward along with altitude; Carotenoid of pericarp were decreased along with altitude.

果肉总糖和果皮叶绿素含量随海拔高度升高先升高后降低；可滴定酸、维生素C和果皮花青苷含量均随海拔升高而升高；蛋白质在1720m处最大，1420m处最小；果皮类胡萝卜素随海拔升高而降低。