中文摘要：

研究了在子区间上奇异摄动的一类半线性二阶微分方程边值问题，用边界层函数法构造出问题的形式渐近解，借助微分不等式理论证明了渐近解的一致有效性．

英文摘要：

A class of boundary value problems for second-order semi-linear dif- ferential equations with singular perturbation on a subinterval is studied. With the method of the boundary layer function, the formal asymptotic solution is con- structed, and its uniformly validity is proved by using the theory of differential inequalities.