利用拓扑度理论研究半闭 1-集压缩算子,在一定条件下得到拓扑度为零的结果以及算子不动点的存在性,所得结果加强了已知文献的结论和减弱相应定理的条件.

Semi-closed 1-set-contractive operators are studied by using topological degree heory. Under some boundary conditions, we get results of the topological
degree zero and existence of fixed points for the opertors. We strengthen conclusion of the known results and weken the conditions of the known results.