Programm control exchanging system of de - xing copper mine 德兴铜矿程控交换系统
Spc exchange fundamentals 程控交换原理
All these changes took place after the first spc exchange was put into service in the capital in 1984 , enabling the use of pcm circuits for local trunks 这是从1984年北京开通第一个程控交换局,首次在市内中继使用pcm数字电路之后巨大的变化。
The telephone network based on circuit - switching and digital program controlled exchanging technology plays an important role in the whole communicating networks 以电路交换和数字程控交换技术为基础的电话网更是在整个通信网中占据着重要的地位。
According to the theory of spc exchange , we devise and develop an experimental system of automatic exchange to meet the need of teaching and practice 本文结合程控交换原理课程及其教学实践要求,开发了一套用于教学演示及实验使用的小型程控交换机仿真系统。