Study on the transformation and upgrading of labor-intensive industries in China 并列题名：Study on the transformation and upgrading of labor-intensive industries in China Study on the transformation and upgrading of travel agency industry Research on the transformation and upgrading of open economy under the new situation in China Research on the transformation and upgrading of urban characteristic industries Research on transformation and upgrading of manufacturing industry cluster in China Research on the transformation and upgrading of China's marine industry Survey on the transformation and upgrading of Chinese firms 并列题名：Research on the transformation and upgrading of open economy under the new situation in China 并列题名：Research on transformation and upgrading of manufacturing industry cluster in China