Abstract: the paper presents the DSL classification, main technique of ADSL, network structure, technical advantages, applications, products, existing problems and so on.
文摘：介绍了DSL的分类及其中ADSL的主要技术、网络结构、技术优势、应用、产品及存在的问题等等。
2
Abstract: this paper mainly introduces the PN of solar cell structure, working principle, classification method and improving the efficiency of conversion.
摘要：该文主要介绍太阳能电池的PN结构、工作原理、分类和转化效率的提高方法。
3
ABSTRACT: OBJECTIVE: To provide reference for improving classification management and specifying standards of retail pharmacies in China.