• 1. second time derivative: 二阶时间导数
• 2. second-time derivative: 二次导数

• 1.The second time derivative is the constant acceleration.
  它的二阶导数就是这个恒加速度。
  dict.yoduao.com
• 2.Moreover, due to the dynamic equations of LPMs with second-order derivative terms in time, the resulting structure-foundation-soil system can be solved by an explicit time-integration method.
  此外，由于模型的动力方程具有二阶时间导数项，因而应用本文模型的结构—基础—土系统可以采用显式时间积分求解。
  dict.yoduao.com

©2026 网易公司