张量场

MGM is introduced to solve field distributions in 3-D electron optical systems. The difference equation, the discrete form of Laplace's equation, is deduced in 3-D Cartesian coordinates. In view of the smooth effect, MGM combines Gauss-Seidel iteration with a technique known as coarse grid correction. Formulae for restriction and prolongation are deduced and expressed in terms of tensors.

将多重网格法引入电子光学系统中三维静电场的计算，对三维笛卡尔坐标系中的差分方程，采用高斯-赛德尔迭代法求解差分方程组，并结合迭代过程讨论了粗网格的误差校正技术；在不同网格层之间进行场值的限制和延拓，推导了三维静电场中的限制、延拓公式并以张量的形式表示。

Vector analysis, Dyads, index notation, covariant and contravariant derivatives, Christoffel symbols, Riemann tensor, hydro-dynamical field equation.

张量及场方程式：三维向量，张量符号，张量微分，克里斯多夫符号，黎曼张量，流体动力场方程式。

The completely diagonalized Hamiltonian matrices of 3d2/3d8 ion configuration in the trigonal symmetry have been established by irreducible representation method. Taken into account the influence of the spin-spin coupling interactions omitted in previous publications, the spectra and the constants of crystal structure and zero-field splitting parameters of CsNiCl3 crystal and CsNiCl3: Mg2+ crystal are calculated and the influence of the doping to the spectra, the constants of crystal structure, zero-field splitting parameters and Jahn-Teller effect are studied. The results show that doping can change the structure of crystal which brings about the changes in the spectra and zero-field splitting parameters as well as Jahn-Teller effect.

应用不可约张量理论构造了三角对称晶场中3d2/3d8态离子的45阶可完全对角化的微扰哈密顿矩阵，在考虑了以前工作中被忽略的自旋-自旋耦合作用的基础上计算了CsNiCl3晶体和CsNiCl3：Mg2+晶体的基态能级、晶体结构、零场分裂参量和Jahn-Teller效应，研究了掺入Mg2+对CsNiCl3晶体的光谱、零场分裂参量及Jahn-Teller效应的影响和自旋单重态对基态能级的贡献，发现掺杂使得晶体结构产生畸变，从而改变晶体光谱的精细结构和零场分裂参量，不改变Jahn-Teller效应的分裂规律但改变分裂的大小。

The color dielectric function and the color magnetic permeability are proposed to describe the color dielectric properties of the QCD medium.

注意到QCD中的场张量也可类比QED中的场张量分解为电分量和磁分量，因此人们也相应地引入了色介电函数和色导率来讨论QCD介质的色介电性质。

Firstly, we collected and sorted out the GPS data, established the uniform velocity field for the Chinese mainland and the surrounding regions, and the horizontal deformation field relative to the Eurasia plate; Secondly, we established a motion model for the entire rotation and homogeneous strain of the first and second level blocks in Chinese mainland, analyzed the motion pattern and strain behavior of active blocks in Chinese mainland, as well as the motion pattern of principal fault zones in Chinese mainland; Thirdly, considering the heterogeneity of strain distribution inside a block and supposing that the strain tensor inside the block is the linear function of location, we derived and established an equation for the entire rotation and linear strain of block and a motion model for the entire rotation and linear strain of principal blocks in Chinese mainland; We also calculated the principal strain field and the maximum shear strain field in Chinese mainland and the surrounding regions, analyzed the basic characteristics of strain field in Chinese mainland, as well as the relationship between the spatial distribution of strain field and large tectonic zones; Finally, we established the 2-D geotectonic model and digital model for Chinese mainland and the surrounding regions, calculated the stress field in Chinese mainland and the surrounding regions, and analyzed the basic features of stress field in Chinese mainland and the principal driving force for the motion and deformation in Chinese mainland.

收集整理了已有GPS资料，建立了中国大陆及周边地区统一的速度场以及相对欧亚板块的水平形变场；建立了中国大陆一、二级地块整体旋转与均匀应变的运动模型；分析了中国大陆活动地块的运动状态，应变状态，以及中国大陆主要断裂带的运动状态；考虑到一个块体内部应变张量空间分布的非均匀性，假设块体内部的应变张量是位置的线性函数，推导建立了块体整体旋转与线性应变方程，建立了中国大陆主要地块整体旋转与线性应变的运动模型；计算了中国大陆及周边地区的主应变场与最大剪应变场，分析了中国大陆应变场的基本特征，以及应变场的空间分布与大型构造带的关系；建立了中国大陆及周边地区二维的地质构造模型和数值模型，计算了中国大陆及周边地区的应力场，分析了中国大陆应力场的基本特征以及中国大陆运动、形变的主要驱动力。

A spacetime point with a frame is proposed to be related to a skew-symmetric tensor field of degree 3 defined on Minkowski space, the field consisting of elements in a fixed tensor set.

场中的张量取自于一个固定的张量集合，我们得到了Riemann正则坐标下引力场的一个级数表示式。

In order to eliminate the effect of noise, wavelet-based denoising technique was used both on diffusion weighted images and noisy tensor field. We also compared the wavelet-based denoising method with the Gaussian smoothing, the traditional denoising method in image analysis.

为降低图像噪声对纤维跟踪的影响，分别采用小波去噪方法对扩散加权图像和张量场进行处理，并对小波去噪和传统的高斯平滑方法在扩散加权图像噪声抑制方面的作用进行了比较。

According to the similar nature of gravitational field and electrostatic field, using analogy method, the stress tensor in gravitational field is obtained from Maxwells stress tensor in electrostatic field, and the universal gravitation inside t

文摘：根据引力场和静电场的相似性质，通过类比方法由静电场的麦克斯韦应力张量得出了引力场中的应力张量，并用它计算了均质球体内部的万有引力。

Theorem 3: the gradient of any point in the locus of foot point of the perpendicular line and the tangent line of the cylindrical spiral is , namely one-order tensor field.

定理3 由坐标原点至圆柱螺线的切线所引垂线的垂足轨迹上任一点的梯度为，即为一个一阶张量场。

According to the similar nature of gravitational field and electrostatic field, using analogy method, the stress tensor in gravitational field is obtained from Maxwells stress tensor in electrostatic field, and the universal gravitation inside the isotropic spheroid is calculated with the obtained result.

文摘：根据引力场和静电场的相似性质，通过类比方法由静电场的麦克斯韦应力张量得出了引力场中的应力张量，并用它计算了均质球体内部的万有引力。

Since historical times,England ,where the early inhabitants were Celts, has been conquered three times .

从有历史以来，英国，在此地早期居住的是凯尔特人，已经被征服了三次。

Bluetooth OBEX File Transfer Enables the sending and receiving of files on your phone via Bluetooth.

蓝牙OBEX文件移动允许经过蓝牙传送和接受文件。。。。