The paper uses the multi-channel audio recording system as the research object, analyzing the prese.

本文以多通道声音记录系统作为研究对象，分析了声音记录系统的现状及其发展趋势。

Some problems concerning the further study and popularization of the digital multi-connected center air-condition units were prese...

指出了进一步研究和推广数码多联机需要解决问题。