Research on quality assurance of career and technical education in the United States Research on quality assurance of international technical and vocational education Research on quality assurance of Chinese-foreign cooperation in running schools Research on quality assurance of international cooperative education in higher vocational colleges Research on quality assurance mechanism of engineering education in Germany 并列题名：Research on quality assurance of international technical and vocational education 并列题名：Research on quality assurance of Chinese-foreign cooperation in running schools Research on employment discrimination law in the united states 并列题名：Research on quality assurance mechanism of engineering education in Germany