It is of interest to note that the ultraconvergence, i . e . with two order higher than the global optimal convergent rate, of the derivatives at the points of interest is obtained by the spr technique for all even-order elements on the uniform meshes in either one or two situation 有趣的是,在一致剖分意义下,无论是一维还是二维情形,对偶次有限元利用spr技术都可以获得节点应力强超收敛结果,即比整体最优收敛阶高两阶的超收敛。