=Publication=The accepted and registered paper will be included in CEES 2020 conference proceedings, which will be indexed by Ei Compendex and Scopus, etc. major databases. =History=*CEES 2019 / July 27-29, 2019 | Nanjing, China--The proceedings of CEES2019 has been published online and it will be indexed by Ei and Scopus soon.*CEES 2018 / July 25-27, 2018 | Vancouver, Canada--The accepted papers have been indexed by Ei and Scopus.