查询词典 isotropic

The constant phase velocities in the direction of the corresponding plane-wave vectors for isotropic media result in three spherical slowness surfaces for each fiber orientation.

这些慢度曲面与各向同性材料中相应平面波矢的相速度为常数的情况不同，对任一纤维方向，都有三个球形的慢度表面。

Theoretically, in spherically symmetric isotropic media, we should not observe rotational signals around the vertical axis before the onset of SH waves.

理论上说，在球对称均匀介质中，在 SH 波到达前不可能观测到绕垂直轴的旋转信号。

To describe why one needs to introduce the concept of static-fluid pressure: it is spherically isotropic.

总体感觉，提问题的人一知半解，对他们的老师太崇拜，在没有完全理解他老师的话的情况下就把这个东西作为挑战题目发到这里了，不知道我的估计对不对。

After a brief summary of the research developments in particle average collision kernel model, correlated mathematic models and numerical simulation algorithms, direct numerical simulations were conducted to study particle collisions in a stationary isotropic homogeneous turbulent flow, with the aim to investigate the influence of turbulence on particle collision kernels of various finite-inertia particles.

本文在系统总结有关颗粒平均碰撞核函数的研究进展和相关数学模型的基础上，基于高效的后溯法来检测碰撞，首先对Reλ约为51均匀各向同性湍流内St_k (St_k=τ_p/τ_k)为0到10的有限惯性颗粒的碰撞行为进行了直接数值模拟，研究了湍流对有限惯性颗粒碰撞的影响。

Then a general expression describing the relation between effective stress coefficient tensor and equivalent connectivity tensor of pore is proposed; and the expression can be applied to isotropic media and also to anisotropic media.

分析了有效应力系数的物理机理及其主要影响因素，在此基础上，提出了等效孔隙连通率的概念，以此表征岩土类孔隙介质的结构和孔隙之间的连通性，建立了有效应力系数张量演化的普适性理论模型。

The isotropic harmonic oscillator is one of the potential fields with strict solution.

1引言各向同性谐振子是量子理论中仅有的几个能够严格求解的可解势场之一。

Using the dual characteristic pairs, we give the if and only if conditions for which a maximally isotropic subbundle of the double of a Jacobi bialgebroid is a Jacobi-Dirac structure.

在此基础上，建立Jacobi流形的两类对应约化定理，并且给出了约化Jacobi流形上的约化Jacobi结构的具体形式以及其与原流形上的Jacobi结构之间的对应关系。

We study the Dirac structures on protobialgebroid, give the integrable conditions for maximally isotropic subbundle being Dirac structure for protobialgebroid by the notion of characteristic pair. From the integrable conditions, we found out that Dirac structure has closed relations with twisting of protobialgebroid. Further, the closed relations are explained, the fact that twisting of protobialgebroids is a equivalence relation is verified.

详细研究了proto双代数胚匕的Dirac结构，给出了极大迷向子丛可积的充要条件，发现在这些充要条件中蕴含了proto双代数胚的扭关系，进一步阐明了扭与Dirac结构之间的内在联系，证明了扭在proto双代数胚范围内是等价关系。

We introduce the notion of characteristic pairs and give the definition of dual characteristic pairs of Dirac structures on Lie bialgebroids. Using the dual characteristic pairs, we give the if and only if conditions for which a maximally isotropic subbundle of the double of a Lie bialgebroid is a Dirac structure.

本文在李双代数胚上，引入了Dirac结构的特征对并给出对偶特征对的概念，利用对偶特征对，给出李双代数胚double的极大迷向子丛是Dirac结构的充要条件；其次，分别利用特征对与对偶特征对，将可约Dirac结构分为第一类可约与第二类可约，在此基础上，建立Poisson流形的两类对应约化定理。

On the ground that the covariance between the disturbing gravity field elements is not isotropic, the covariance matrix has a complicated structure (its submatrix being not repetitive Toeplitz matrix) and thus its degree cannot be degraded with transformation matrix method, so it cannot be put into practice. So far, the application of least squares collocation to the modeling and data processing of the horizontal disturbing gravity field observations has not been found in literature.

由于水平扰动场元之间的协方差并非各向同性，导致协方差矩阵结构复杂(子矩阵不是 Toeplitz 循环阵)，不能利用变换矩阵将其降阶，无法付诸实践，迄今尚无最小二乘配置理论应用于水平扰动场元观测量的模型化公式和数据处理方法。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。