关键词: 低碳技术, 合作创新网络, 多维邻近性演化, 社会网络分析, 低碳汽车

Abstract: Based on the realistic consideration of climate change and energy security, low-carbon technology (LCT) innovation has become an important global issue. Multidimensional proximity is a new perspective of innovation research at home and abroad. However, the evolution of multidimensional proximity in the LCT collaborative innovation network is rarely studied. In recent years, the globe’s focus on reducing the environmental impact of vehicle emissions and fossil energy consumption has driven low-carbon vehicle technology (LCVT) innovation. In response to this significant change, this paper takes LCVT as an example to inspect whether there is multidimensional proximity in the LCVT collaborative network, and analyze the evolution of multidimensional proximity.At first, this paper analyzes multidimensional proximity and its evolution in the LCT collaborative innovation network theoretically. We propose that multidimensional proximity is an important driving force for innovation, which plays an important role in promoting the construction of partners as well as the development of LCT collaborative innovation network and evolves with the development of LCT as well as innovation networks.Then, this paper constructs the global 1992-2011 LCVT collaborative innovation network based on joint patent application data, which comes from the patent application data in the field of LCVT in the world's authoritative patent intelligence platform—Derwent database. Referring to the definition of new energy vehicles, "low-carbon vehicles" as the research object in this paper mainly refer to hybrid vehicles, pure electric vehicles and fuel cell vehicles classified by power sources. Based on the change trend of global LCVT innovation patent number and the annual distribution comparability requirements, while considering the issued time of relevant global low carbon policy, this paper extracts the collaboration matrix of patent applicants in the four stages of 1992-1996, 1997-2001, 2002-2006 and 2007-2011 through manual collection and data mining. Next, this paper uses social network analysis software UCINET to build global LCVT collaborative network, and uses the method of combining whole network with egocentric network to analyze the evolution of multidimensional proximity in the global LCVT collaborative network. The conclusions are as follows: firstly, LCT and its collaborative innovation network co-evolve with multidimensional proximity. In the past 20 years, proximity has continued to evolve, research & development area has broadened, collaborative relationship has expanded, collaborative intensity has deepened generally, the number of patent applications has increased, mutual learning, knowledge compatibility and organization compatibility have improved, and structural holes have developed more fully. The formation of new connections helps actors constructing their own structural holes to enjoy the advantages of information control and information access, therefore enhance the innovation capabilities of LCT. If the actors at both ends of the structure holes are connected to its advantage, then the actor living in the structure hole is willing to act as a bridge to enrich the existing network structure. Toyota, for example, provides platforms for collaboration among its suppliers. Overall, the actors become more closely connected, the number of cliques and network centrality have continue to increases, collaboration is more concentrated among central actors, patent output gradually increase and jumped sharply in the later period. This obtains benefit from the acquisition and accumulation of knowledge, experience, trust, reputation, norm and routine, as well as the attention and support of the state. The joint action of mechanisms such as attraction & agglomeration, integration & consolidation, interaction & learning, social embeddedness and decoupling tend to promote the co-evolution of LCVT collaborative innovation network and geographical, organizational, cognitive and social proximity. Secondly, multidimensional proximity’s evolution in the LCT collaborative innovation network involves the network status and capability evolution of different countries & regions and actors. In the evolution of LCVT collaborative innovation network and the multidimensional proximity, although the actors’ development paths are different, core actors such as Toyota are always in an advantageous position in the network, and have the advantage of information control and information access. In addition, position resources and innovation capabilities of some other actors such as Hyundai and BMW have strengthened increasingly. Core enterprises, as the main forces of LCT innovation and diffusion, tend to select neighboring actors to establish connections to promote the diffusion of low-carbon technology. The total number of cliques is increasing, whose country & regions and actors composition are presenting a trend?of?diversification, and the participating enterprises from other countries are mostly affiliated enterprises or neighboring enterprises with cooperative history. The number and the growth rate of cliques constituted by Japanese actors are higher than other countries or regions, which makes it easier to form a mutually beneficial cooperative relationship. This is mainly because the number of European and American actors is less than that of Japanese actors in the network, and most of actors from European and American are enterprises with a high degree of globalization, which have a longer history of interaction. On the other hand, Japanese enterprise groups are more closed in organizational culture and organizational system.Thirdly, the evolution of multidimensional proximity in the LCT collaborative innovation network needs to be paid attention to in the "locking effect" of excessive proximity. In the first stage, when the degree of network cohesion and compactness are not high, the average distance between actors is relatively small. When the degree of network cohesion and compactness increase slightly in the second stage, the average distance increases slightly, and more actors are needed to connect two actors in the network on average. This partly reflects the tendency of "proximity locking" as the multidimensional proximity evolves. This trend continues to decline during the latter decade and the overall organizational connectivity increases. In future, during the evolution of LCT collaborative innovation network and multidimensional proximity, it is necessary to find the balance point between partner proximity and network closure, so as to avoid excessive conformity pressure, high relationship maintenance cost, high knowledge management costs and too much homogeneous knowledge, thus hindering the development of LCT innovation. This could be brought about by the high degree of attraction & agglomeration, learning & reinforcement, norm & routine sharing, and environmental embeddedness, which may come with LCT collaborative innovation network of excessive proximity and density.

Key words: low-carbon technology, collaborative innovation network, social network analysis, multidimensional proximity evolution, low-carbon vehicle