【摘要】 本文得到了Ⅱ型循环拟差集的一个基本性质和两个重要的不存在性定理．给出了ｖ＝３ｍ时Ｒｙｓｅｒ关于Ⅱ型循环拟差集的一个结果的另外一种证法．并给出了几组Ⅱ型循环拟差集不存在的参数．更多还原

【Abstract】 in this paper, we obtain a property and two important nonexistence theorems of near difference sets of type 2. Another proof of one of Ryser’s theorems with respect to near difference sets of type 2 is given. And also we give several classes parameters that near difference sets of type 2 do not exist.更多还原