Abstract:     In the establishment of a "dual circulation" development pattern, we regard the Belt and Road Initiative as a quasi-natural experiment of high-level international circulation. Further, we have constructed a policy identification framework to examine the impact of external circulation on enterprise technological innovation, which includes the difference in difference model, the difference in difference in difference model, and the mediating effect model.
    Based on the existing literature and the international situation, we define a high-level international circulation as a new round of opening-up process, with a global governance mechanism of extensive consultation, joint contribution and shared benefits. Compared with the traditional international circulation, it has advantages in terms of trade structure, production methods, and industrial chain cooperation models. Considering that the Belt and Road Initiative drives the international circulation to a higher level, this paper analyzes the changes brought about by the Belt and Road Initiative in external market demand, factor market supply, and enterprises′ own risk areas. According to the conclusion, we further explored the triple effect mechanism of high-level external circulation on enterprise technological innovation.
     This paper uses data from China′s A-share listed companies from 2008 to 2017, empirically analyzing the impact of the initiative on the technological innovation of Chinese enterprises. We find that the high-level international circulation has a significant positive effect on the technical change. Taking into account the innovation motivation, the initiative can promote both the company′s substantial technical change and strategic technical improvement. In addition, the results show a heterogeneous influence under company′s different basic levels of innovation, which is particularly good for low basic level enterprises. As results, the high-level international circulation has brought a substantial technological change and balanced economic development.
    Further research find that external market expansion, innovation factor integration, and survival risk avoidance are the three major mechanisms affecting enterprise technological innovation. Specifically, the external market expansion mechanism means that enterprises can obtain new external demand and stimulate technological innovation by expanding their trade to markets along the Belt and Road Initiative. And the innovation factor integration mechanism means that international circulation promotes technological innovation of enterprises by promoting the accumulation of R&D funds and R&D personnel in the domestic market. The survival risk avoidance mechanism refers to the indirect effect brought by risk aversion. Because it avoids the survival risks that may exist in foreign investment, the high-level international circulation provides a good development environment for the enterprise and ensures the sustainability of enterprise innovation. Finally, high-level international circulation drives continuous technological innovation on both market demand side and factor supply side. In addition, R&D talents play an important role in both innovation factor integration mechanism and survival risk avoidance mechanism, and shoulder the double responsibilities of "promoting innovation and reducing risks".
   We have obtained some managerial insights and policy recommendations. First of all, Chinese enterprises, especially those with a low level of innovation foundation, should deeply participate in cooperation along the Belt and Road Initiative, and improve technological innovation by integrating into a higher level of international circulation, to achieve technological independence and solve the supply chain crisis. Secondly, the government should encourage and lead domestic enterprises to find new opportunities in countries along the Belt and Road Initiative, and help microeconomic entities re-plan their supply chain to deal with international market risks. Thirdly, the government can support enterprises to participate in a new round of international circulation and to build a "reservoir" of innovative factors by direct subsidies or indirect credit support. Finally, through the Belt and Road Initiative talent exchange project, the Chinese government should improve the talent introduction and training mechanism and let them play the role of promoting innovation and reducing risks.

Key words: new development paradigm, international circulation, technological innovation, the Belt and Road Initiative