returned material

However, under the Extensive management pattern in Chinese coalmine industry, the management pattern that coalmine production enterprises use to returned logistics and waste material logistics in coalmine production logistics system will cause tremendous waste of resources, and the management efficiency is extremely low.

然而，在我国煤炭行业粗放式管理模式下，煤炭生产企业对煤矿生产物流体系中回收物流和废弃物流的现行管理方式不但造成极大的资源浪费，而且管理效率极其低下。

2,311 valid and returned questionnaires were received and the items of questionnaires included eight dimensions: technical support, instructional design, course material design, website design, flexibility, student-student interaction, teacher support, and assessment.

本调查收回有效问卷2311份，内容包括八个方面：技术支持、教学设计、内容设计、网站设计、灵活性、学生互动、教师支持，以及学习评估。

Research of Utilizing The Returned Material of The Fe-Cr-Co Permanent Magnet

Fe Cr Co永磁合金返料利用研究