The quantitative evaluation of the timbre is given by testing the empty yard reverberation time and calculating the full yard reverberation time of the gymnasium in China Three Gorges University.
通过对三峡大学室内体育馆空场混响时间的测试及对满场混响时间的推算,给出了定量的音质评价。
This paper introduced the test study, stoping and cutting layout, stoping characters and technical economical effect of explosive transportaiton sublevel open stoping in Tongshan Coppcr Mine, Tongling Nonferrous Metals Group Company.
介绍了爆力运搬分段空场采矿法在铜陵有色金属(集团)公司铜山铜矿的试验研究,该采矿方法的采切工程布置,回采工艺特点以及技术经济效果等。