dulac meaning in English

迪拉克
杜拉克

Assume that . in this paper , we will discuss the existence , the non - existence and the uniqueness of limit cycle system ( * ) . the methods employed are poincare - bendixsion theorem , method of dulac function and zhang zhifen ' s uniqueness theorem . our main results are as follows : theorem 1
对的情形,我们讨论了系统（ * ）极限环的存在性、不存在性和唯一性。主要利用环域定理、 dulac函数法和张芷芬的唯一性定理等手法。