中文摘要：

本文研究二阶椭圆方程基于泡函数的稳定化的二阶混合有限元格式，通过消去泡函数导出一种自由度很少的简化的稳定化的二阶混合有限元格式，误差分析表明消去泡函数的简化格式与带有泡函数的格式具有相同的精度而可以节省6Np个自由度（其中Np三角形剖分中的顶点数目）．

英文摘要：

In this paper, a stabilized second order mixed finite element formulation based on bubble functions for second-order elliptic equations is studied, and a simplified second order mixed finite element formulation with less freedom degrees is obtained by eliminating all bubble functions. It is shown by analyzing error that the convergence of the simplified and stabilized second order mixed finite element formulation eliminated all bubble functions is the same as that of the stabilized second order mixed finite element formulation with bubble functions, but it can save 6Np freedom degrees （where Np is the number of vertices of triangulaxization）.