As the oil industry tightens its belt after the worst price slump in a generation, the state-owned giants of the Middle East are taking the opposite tack. Saudi Arabian Oil Co., Abu Dhabi National Oil Co. and Kuwait Petroleum Corp. are using a record number of drilling rigs and boosting production, a contrast to international companies from Exxon Mobil Corp. to Royal Dutch Shell Plc, which are shelving projects and slashing costs.