Asiana Airlines Inc., South Korea's No. 2 flag carrier, said Tuesday that it is seeking to launch a low cost carrier in a bid to expand its share in the budget airline market. "The company is studying plans to set up a budget carrier that might use Incheon International Airport and Gimpo International Airport for its main bases," said an official at Asiana. "Details have yet to be decided and the company will convene on the move as soon as possible."    Asiana already holds a 46 percent stake in Air Busan Co., which is based in Busan, 453 kilometers southeast of Seoul.