This paper discusses the purposes and significance of research of ECAP,the principle of ECAP,its progress in research and its five problems urgent to be solved.

• 本文阐述了ECAP的研究目的与意义,说明了ECAP的原理,探讨了ECAP的国内外研究现状及进展,指出了ECAP急待解决的五大问题,具有较好的实用价值。