A retired army general who holds a doctorate in economics was sworn in Wednesday as Indonesia's first directly elected president and announced a cabinet that reflected his style as a cautious reformer.

Susilo Bambang Yudhoyono was elected by a landslide one month ago, defeating President Megawati Sukarnoputri. Yudhoyono, 55, begins his five-year term with public expectations running high that he will bring stability to a country that has had four presidents since the longtime dictator, Suharto, was ousted after protests in 1998.

"I have to remind you all that the complicated and complex problems of the nation cannot be solved within the period of a hundred days. It is not as easy as turning over the palm of your hand," Yudhoyono said in his inaugural speech at the presidential palace. "But I'm convinced that our determination and good intentions are more powerful than the problems we face."

He said he would focus on domestic affairs, cataloguing challenges from unemployment and corruption to terrorism and separatist conflicts in the outlying provinces of Aceh and Papua.

Yudhoyono also singled out the rising price of oil, which could represent an early test for his administration. Government subsidies have increased in recent months to maintain artificially low consumer fuel prices, and Yudhoyono must soon decide whether to cut the popular subsidies or risk wrecking the national budget.

Earlier in the day, appearing at parliament wearing a blue suit and traditional black Muslim cap, he read the oath of office from a brown batik folder, as a religious leader held a copy of the Koran, the Muslim holy book, above his head. Outside, more than 2,000 police officers stood guard.

Security forces in Jakarta have been on alert since the August 2003 bombing of the JW Marriott Hotel, which killed 12 people. Last month, a truck bombing outside the Australian Embassy killed nine people. Both attacks were blamed on Muslim extremists.

Yudhoyono's inauguration as the leader of the world's largest Muslim nation drew lawmakers, judges, ministers, diplomats and the leaders of five neighboring countries. Megawati did not attend, and reportedly spent the morning gardening at her home in the south of the capital.

Most of the cabinet ministers named by Yudhoyono were described as advocating measured changes in the country.

"He wants reform, not a big bang, but a systematic and gradualist approach. That's the message from his cabinet appointments," said Bambang Harymurti, editor of Tempo, a weekly magazine.

The post of attorney general has drawn the most public interest because it is central to fighting graft in a country that was ranked by Transparency International, which analyzes government openness, as among the most corrupt in the world. Yudhoyono gave the job to Abdul Rahman Saleh, a Supreme Court justice who cast the only dissenting vote this year when a five-judge panel cleared the former parliament speaker of graft charges. But several analysts said they were waiting to see whether Saleh's courage extends to tackling the many vested interests that benefit from Indonesia's corrupt legal system.

For chief security minister, Yudhoyono named retired Adm. Widodo Adisutjipto, a former armed forces commander, who will have significant influence in military affairs. He will face demands from activists and some lawmakers to reform the powerful armed forces by placing the military under civilian control and restricting its role in politics and business.

Yudhoyono's chief economics minister will be Aburizal Bakrie, a businessman and former head of the Indonesian Chamber of Commerce who has close ties to the Golkar party of former president Suharto. Jusuf Anwar, an Asian Development Bank director, will become finance minister.

The new administration will seek to reinvigorate the economy, which is growing too slowly to accommodate the estimated 40 percent of the workforce now either jobless or underemployed.

Yudhoyono is expected to play a central role in economic policy. Days after his election victory, he received an economics doctorate from the Bogor Institute of Agriculture, having written a dissertation on the role of agricultural development in alleviating poverty.

Susilo Bambang Yudhoyono said he would focus on domestic issues.