Research on the social security system in Asian countries and regions History of the social security system in western countries Research on the national security system and mechanisms of main countries in the world Research on social security system in rural China Research on the political system and security system of major countries in the world A study on the social security system in the United States of America Research on the social security for the elderly and the disabled Research on constructing Chinese social security system based on coordinated urban and rural areas Research on rural social security legal system in China Research on information security accountability system international comparison and reference