Sony Ericsson Mobile Communications named Hideki Komiyama as its new top executive on Tuesday as it announced that Miles Flint will step down for personal reasons. Mr. Flint, who became president of the company in 2004 and helped bring the venture to profitability, will remain executive adviser to Mr. Komiyama, currently chairman of Sony Electronics, until the end of the year. Mr. Komiyama will take up his position Nov. 1. Sony Ericsson, based in London, was founded in 2001 as a joint venture of Ericsson of Stockholm and Sony of Tokyo.