SYDNEY : The dollar rose against the yen on Monday after Japan's top central banker flagged further policy tightening ahead but left open the question of timing, leaving the market no clearer on whether a move would come next month. Bank of Japan Governor Kazuo Ueda reiterated that interest rates would continue to rise gradually should the economy develop in line with the central bank's outlook. However, he made no mention of whether a hike would come in December, saying the BOJ would need to