中文摘要：

将含有3条超边的超圈存取结构分为两类：一类是任意一条超边都没有属于自己的独立点集;另一类是至少存在一条超边有属于自己的独立点集。对第一类超圈存取结构,用Shamir方案构造了一个理想的秘密共享方案,从而证明了其最优信息率等于1;对第二类超圈存取结构用信息论和λ-分解方法证明了其最优信息率等于2/3。给出了参与者人数为6、7且含有3条超边共86种互不同构的超圈存取结构,并计算了其最优信息率。

英文摘要：

The hypercycle access structures with three hyperedges is divided into two kinds： one kind is that any hyper- edge has no its own independent point set, another kind is that there is at least one hyperedge which has its own inde- pendent point set. By using Shamir-threshold scheme, an ideal secret sharing scheme is constructed, and it is proved that the optimal information rate of the first kind of hypercycle access structures are equal to 1 ; Using information theory and A-decomposition method, it is shown that the optimal information rate of the second kind of hypercycle access struc- tures are equal to 2/3. Eighty-six hypercycle access structures with three hyperedges on six and seven participants, in which all of each other are not isomorphic, and their optimal information rates are calculated.