Based on the nonlinear equations of the theory of density wave, the evolutionary direction and the observable conditions on spiral galaxies may be derived by the qualitative analysis theory.

基于密度波理论的非线性方程，用定性分析理论可导出旋涡星系的演化方向和由观测可得到的演化条件。

youdao

The paper introduces the present knowledge of the theory and technology of diffusion photon density wave (DPDW) which have been focus of the recent research.

本文介绍了目前生物医学光子学领域内引人注目的新技术— 扩散光子密度波技术的理论基础、 系统及国内外的最新进展。

youdao

The structural stabilities and electronic structures of W atomic chains are studied by employing first-principles plane wave pseudopotential method based on the density functional theory.

使用基于密度泛函理论的第一原理平面波赝势法，研究了W原子链的结构稳定性和电子结构性质。

youdao