INTabbr.(=interior)内部的abbr.(=international)国际的abbr.(=interjection)感叹词abbr.(=intelligence)智力intestacyn.未留遗嘱而死亡

1. The existence of periodic solutions of a neutral integro-differential equation with infinite delay was studied.
   摘要本文考虑具无穷时滞中立型积分微分方程周期解的存在性。
2. The use of expression such as these for the aerodynamic forces converts the differential equations of motion into integro-differential equations.
   如对空气动力采用这类表达式，就将运动的微分方程变换成积分微分方程。