Research On Identification Of Technological Trajectories

With the theoretical progress the technological trajectory research, the identification of technological trajectory research has become the most important part of the theory of technological trajectory. The identification of technological trajectories bases on the quantitative research. This dissertation studies the identification of technological trajectories with the main path analysis (MPA) which bases on the patent citation network.With the deep research on the classical main path analysis, this dissertation studies the method from the composition of the main path analysis. There are four parts of the classical main path analysis. They are the topological order of citation network, the algorithm of transversal weight of edges, the criterion of the option of main path and the determination of the star point (origin) of main path.There are a lot of application of the classical main path analysis on the discovery of the technology trends and science progress. However, the flaws of the method have been explored by many scholars. In this dissertation, the flaws of the main path analysis have been concluded into4aspects, which are invariance property, over-selectivity, unicity and the limitation of algorithm. The main path analysis method can be extended with the optimizing of the algorithm, integrity of the other methods. The optimizing of the algorithm includes:from local view to global view, from single to multidimensional of the selection of path algorithm; the determination of the topological order of the citation network and the determination of the start point of the main path.The procedure of the identification of the technological trajectories with main path analysis has been proposed. With the analysis of the inner mechanism of the identification of the technological trajectories and patent citation networks, this dissertation proposes the procedure of the identification of the technological trajectories with main path analysis of patent citation network. This dissertation makes a thorough research on the demands of the identification of technological trajectories with the main path analysis or the variation or extension of this method. The program is included:the selection and determination of the technological domain; the construction of patent network; the selection of methods and softwares of identification of technological trajectories and the engineering analysis of the technology information of the patents composing the main path.The last part of this dissertation is the empirical analysis. The empirical analysis includes two technological domains, and for each domain the one-step and two-step patent citation network has been analyzed. Except the sub-network extraction and classical main path analysis, the extended main path analysis has also been conducted.