查询词典 tensor density

Objective To explore the clinical value of MRI and MR diffusion tensor imaging in amyotrophic lateral sclerosis.

目的探讨常规MRI检查和MR扩散张量成像新技术在肌萎缩侧索硬化症中的临床应用价值。

Objective To investigate the involvement of upper motor neuron in amyotrophic lateral sclerosis patients using diffusion tensor imaging.

目的采用DTI技术，定量检测肌萎缩侧索硬化症患者脑内上运动神经元的受累情况。

The computation of conformal rotational vector from rotational tensor and angular velocity is also studied, and the linearized formulation of angular velocity and acceleration is given.

为便于将该理论应用到多体系统动力学的建模中，还讨论了如何从转动张量和角速度中提取相应的保角转动矢量；以及角速度和角加速度的线性化问题。

We show that the differences between the results of our approach and the previous for the axial vector and vector vacuum susceptibilities are large, while that for the tensor vacuum susceptibility is small.

结果表明，我们的方法在计算轴矢量和矢量真空磁化率时与以前的方法相比数值差别是很大的，而张量真空磁化率的差别不大。

In studying the linear response of the dressed quark propagator in the presence of the variable external field, we derive a general expression for the vacuum susceptibility, based on the two-point external field formula in the Quantum Chromodynamical sum rule. The expressions we have derived for the calculation of vacuum susceptibility are model independent. Then we use the expressions to calculate the renormalised axial vector, vector and tensor vacuum susceptibilities.

接下来在研究夸克传播子在外场中的线性响应时，我们利用QCD求和规则两点外场公式推导出了一般的计算真空磁化率的公式（以变化的轴矢量外场为例），我们这里推导出的真空磁化率的计算公式是模型无关的。

The material's elastic constants for different orientations are obtained from the elastic constants along the axis of symmetry through the regular tensor transformation law.

不同旋转角度时材料的弹性常数是从晶轴坐标系下的弹性常数通过张量变换得来的。

Secondly, we discuss the boundary value problem of two dimensional biharmonic equation in a rectangular field and its variational problem,discretize it by using dual tensor product of and the direct product and lining up of matrices, we get some special matrices which are the presupposition in exploring the fast computation, then solve the system of linear equations.

其次本文讨论了矩形域上二维双调和方程边值问题及其相应的变分问题，利用二元张量积小波分析和矩阵的直积、拉直技巧将变分问题离散化，从而使求解偏微分方程问题变为求解线性方程组的问题。一维情况两组基的张量积下得到的系数矩阵分别为块状七对角阵和稀疏矩阵。这些特殊结构为以后快速算法的研究打下一个基础。

It is true that the discrete version of Korn's second inequality does not hold in the standard Crouziex-Raviart 1 element space. In [24] , the strain tensor was modified, at the same time, the bilinear form changed, as a result the modified discrete version of Korn's second inequality holding in the standard Crouziex-Raviart 1 element space.

我们知道，在标准的Crouziex-Raviart 1元空间中第二Korn不等式的离散形式是不成立，Falk在[24]中修改了应变张量，相应的弹性问题的双线性型也被修改，这样，修改后的第二Korn不等式的离散形式在标准的Crouziex-Raviart 1元空间中成立。

In this paper, a "two-molecule" model of ellipsoidal drop was established.And then the ellipsoid situation was transformed into sphere situation by coordinate transformation.By utilizing bipolar coordinates and Maxwell stress tensor, the expression of electrostatic radial and tangential forces between two drops was deduced.

通过建立水滴的"二分子"椭球模型，利用坐标变换把椭球问题转换成圆球问题，并运用双球面坐标和Maxwell应力张量理论，推导出两椭球水滴间的径向和切向电场力的表达式。

Generalized Darcy's law was first derived from the study of fluid flow through a solid-fluid mixture,and the saturated permeability tensor of a preform could be predicted by studying its unit cell under periodic boundary conditions.

首先，采用均匀化理论分析了流体在多孔介质内的流动问题，推导出广义达西定律，证明以施加周期性边界条件的单胞为研究对象，可以预测预成型体的渗透率张量，并以单向纤维织物为例，对该方法进行了验证。

The dissecting of samples in group2 were difficult. The root of pulmonary artery and ascending aorta failed to be unfolded because fibrous tissue was tough, right and left fibrous trigone were too firm to be solved by hand. Cardiac muscle fibers couldn't be stripped along myofibrillar trajectory since they were prone to break because of their friability.

组2的心脏解剖困难，表现为纤维组织坚韧，游离肺动脉非常困难；徒手无法松解左、右纤维三角，肺动脉和主动脉根部的游离非常困难；心肌纤维坚硬、质脆，解剖时容易断离成碎块，无法沿纤维走行方向剥离。

We have battled against the odds in a province that has become increasingly violent.

我们对在一个争夺日益激烈省的可能性。