冲原丰是日本著名比较教育学家，比较教育社会科学方法时代的重要代表人物。

OkiHara Yutaka is a leading scholar of Comparative Education in Japan and an important representative in the times of social science methods in Comparative Education.

youdao

丰山铜矿南缘矿带开采技术条件复杂，原采用的无底柱分段崩落法在生产中存在较大问题。

Because of the mining condition of ore belt of southern edge in Fengshan Copper Mine is more complicated, the originally used sublevel caving method in the production have obvious shortcomings.

youdao