场合 shu zi xin hao chu li de ying yong chang he qi kan
有哪些 shu zi xin hao chu li you na xie he xin qi kan
数字信号 shu zi xin hao fang mian de guo nei ding ji qi kan
数字化 检索系统 信息 wan fang shu zi hua qi kan xin xi jian suo xi tong
移动通信 因子 通信 tong xin qi kan yi dong tong xin ying xiang yin zi
字数 c s s c i qi kan zi shu 2 0 0 0 0 zi