外四家
外四家-
基于上述研究问题，本文采用了案例分析和案例比较的研究方法，主要研究了国内外四家汽车企业的专利申请情况，并重点分析了东风汽车公司的专利申请和专利管理工作。
Based on the above topic , the thesis adopts the methods of case study and case comparison . It mainly studies patent application of four auto companies , especially in analyzing patent application and patent management of DongFeng Motor Corporation ( DFM ) .