关键词: &ldquo, 一带一路&rdquo, ；科技合作；社会网络分析

Abstract: Since the Belt and Road Initiative has been advanced in the year of 2013, more and more countries in this area have developed science and technology cooperation with each other. Some researchers have studied the science and technology cooperation among countries along the Belt and Road. Most of the existing literature explores the science and technology cooperation between China and some major countries along the Belt and Road by using the research method of scientometrics. However, it did not analyze the overall status of scientific and technical cooperation between all countries in the area with the research method of social network analysis. Moreover, although the existing literature studied the evolution of science and technology cooperation among countries along the Belt and Road by contracting the cooperation in different ages, it did not contract the scientific and technical cooperation among countries in the Area in different technical fields. Accordingly, based on the information of transnational PCT patent application collaboration of countries along the Belt and Road which was searched from Incopat patent information platform, this paper established the scientific and technical collaboration networks in five different technical fields of countries along the Belt and Road. It analyzed the network visible graphs, network overall structure indicators and network centrality indicators with social network analysis method.
On the basis of the findings, it explores the similarities and differences of science and technology collaboration networks in different technical fields of countries along the Belt and Road so as to provide suggestions for reference and promotions for countries in the area to make and implement a suitable science and technology collaboration policy.
On the one hand, this article finds that the scientific and technical collaboration networks in different technical fields of countries along the Belt and Road have three important similarities. First, the cooperation breadth and cooperation depth of nodes of each science and technology collaboration network in different technical fields of countries along the Belt and Road seem to be obviously different. Second, five science and technology collaboration networks in different technical fields of countries along the Belt and Road have the followed common characteristics: relatively big network scale, low network density and short average distance. This illustrated that although most of the countries along the Belt and Road have taken part in the science and technology collaboration the collaboration relationship in the networks is not close enough and there are enormous opportunities for collaboration in the networks. Third, almost all of the core nods of science and technology collaboration networks in different technical fields of countries along the Belt and Road are richer countries in this area. 
On the other hand, this article finds that science and technology collaboration networks in different technical fields of countries along the Belt and Road have three significant differences. First, big nodes and the collaborative pair of countries connecting by thick line are different in scientific and technical collaboration networks in five technical fields of countries along the Belt and Road. This means that the country which has collaborated with the most nodes and the pair of countries which have collaborated for the most times are different in science and technology collaboration networks in five technical fields of countries along the Belt and Road. Second, science and technology collaboration networks in different technical fields of countries along the Belt and Road are classified into different types. The science and technology collaboration networks in the fields of instruments and other fields have low network scale and low network density. Thus, both of the networks in the two fields are grouped into Newborn Model network. The strategy for developing Newborn Model network is to enlarge the number of nodes of the science and technology network. The science and technology collaboration networks in the fields of electrical engineering and mechanic engineering have relatively high network scale and relative low network density and are defined as Youngster Model. Youngster Model network should not only enlarge the number the nodes but also strength the collaboration between the existing nodes. The science and technology collaboration networks in the field of chemistry is close to Adult Model because this network has relatively high network scale and relatively high network density. Adult Model network should focus on increasing the existing collaborating between nodes in the network. Third, the distribution and order of core nodes of science and technology collaboration networks in different technical fields of countries along the Belt and Road are different. For example, the first core node of science and technology collaboration networks in fields of chemistry, mechanic engineering, instrument and other fields is Russia, yet that of science and technology collaboration network in field of electrical engineering is China.
The finding above shows that, all of the science and technology collaboration networks in different technical fields of countries along the Belt and Road have the problem that few richer countries have more powerful influence in the network and the overall collaboration relationship is not close enough. Science and technology collaboration networks in five technical fields of countries along the Belt and Road have various differences. The development of scientific and technical collaboration network in chemistry of countries along the Belt and Road is relatively mature compared with those of other technical fields. Besides, most countries along the Belt and Road may have different influence scientific and technical collaboration networks in different technical fields. According to the research results, this article points out that countries along the Belt and Road should make a reasonable choice of strategic technical fields on the basis of their own development need, and make a proper policy so as to push forward transnational science and technology collaboration with their own characteristics step by step.

Key words: the Belt and Road, scientific collaboration, social network analysis