South Korean President Lee Myung-bak nominated Thursday the head of a national trade promotion agency as the new minister of knowledge economy, Lee\'s office said. Hong Suk-woo, head of the state-run Korea Trade-Investment Promotion Agency (KOTRA), will replace Choi Joong-kyung, who offered to resign over rare nationwide blackouts last month, according to Cheong Wa Dae. Hong now faces a parliamentary hearing, a formality. The president also named Eo Cheong-soo, former National Police Agency chief, as head of the presidential security service. Eo is to replace Kim In-jong, who offered to step down earlier this month to shoulder responsibility for the controversial purchase of land for Lee\'s retirement home. The president has scrapped the plan to build his residence in an affluent Seoul neighborhood following press allegations of irregularities surrounding the land deal.