This document discusses research on tracking the trajectory of technological development from initial invention to commercial innovation. It focuses on the development of blue LEDs as a case study. The researcher aims to 1) determine the path from invention to innovation and 2) track the trajectory from scientific discoveries to innovation. The methodology involves building a "citation tree" network of over 1,000 patents and papers related to blue LED development from 1903 to 2007. Key findings include the identification of "cru nodes" or influential inventors that connected different organizations, especially in the 1970s. Many cru nodes held patents from major firms. The research finds these inventors played a role in knowledge sharing beyond their typical inventive work. Overall, the study uses quantitative citation analysis

1. Crunode in Technological Development Hitotsubashi University JSPS DC1 Yasushi HARA 1

3. Quantitative approach

4. Qualitative approach

5. 2.) how do we track the trajectory from the science discoveries into innovation?

6. The origin of innovation.

7. Spillover and scientific base.2

8. Technological development Invention Innovation Invention Invention Invention Invention Invention Invention Invention Invention time 0 3

10. (Martinelli; 2010)

11. Role of prior researches

12. (Comroe and Dripps; 1976)

13. Star Scientist Thesis: (Zucker and Darby; 1997)

14. Knowledge and Innovation

15. (Mokyr; 2003)

16. Knowledge Management: (Nonaka and Takeuchi; 1995)

17. Open Innovation: (Chesbrough; 2003, 2011), (Chesbrough and Vanhaverbeke; 2006)4

19. To capture up the trajectory of technological development numerically, build up “citation tree” for

20. 1.) Ensuring the role of organization.

21. 2.) Identifying the “main path (= most influenced patent and/or paper in each decade)” of trajectory.

22. 3.) Under 1.) and 2.), determining whether the existence of “cru node "scientist [talks later].

23. Field

24. Based on quantitate approach:

25. Blue LED (invented by Dr. Shuji Nakamura [ex. Nichia Corporation] )

26. Data

27. Patent [USPTO, JP Patent Library] / Paper [ISI Web of Knowledge/Science]5

28. “Citation Tree” build algorism 1: Defining the starting point: Shuji Nakamura’s most-cited patent [US7205220] for blue LED.2: Referring [inventor-cited] whole forward citation data of starting point3: Under 2., referring forward citation data of 3-tier paper and/or patents.4: Repeating these procedure for 5 times.Sum: Fetches about 1,000 paper/patents and its forward citation data. [from 1903 to 2007] Starting point 6

29. Entire Network Red node indicates the “Main path”. Source: Web of Knowledge[Derwent Innovation Index]/Web of Science

30. Network (delete pendants) Red node indicates the “Main path”. Source: Web of Knowledge[Derwent Innovation Index]/Web of Science

31. 1910-1970 1960s 1970s 1930s Source: Web of Knowledge[Derwent Innovation Index]/Web of Science

32. 1910-1975 1960s 1970s 1930s 1975 Source: Web of Knowledge[Derwent Innovation Index]/Web of Science

33. 1910-1980 1960s 1970s 1930s 1975 1980 Source: Web of Knowledge[Derwent Innovation Index]/Web of Science

34. Top 10 companies from 1910-2007 1930s 1960s 1970s 1990s 2000s 1980s Source: Web of Knowledge[Derwent Innovation Index]/Web of Science

35. “Main path” of Paper and Patent (1910-2007). Source: Web of Knowledge[Derwent Innovation Index]/Web of Science

36. Cru Node in the Network Cru node [definition]: the certain node which connects certain scale of social groups and/or organizations. Brief Result Papar? Patent? : Mostly Patent. Who? : resides in big firms, and yields many papers/patents. When? : Mostly 1970-1975. How? : total backward-citation number is low, comparing to average of his/her another paper/patents.

37. Cru node in the network [Graph] Source: Web of Knowledge[Derwent Innovation Index]/Web of Science

38. Cru Node in the Network [Table]

39. Behavior of “Cru Node” Scientist Case 1: Jacques Pankove・“Jacques Pankove was born in Russia in 1922 and lived in France for nearly 20 years. To evade Nazi persecution, Jacques and his family came to the United States in 1942, where he became an accomplished electrical engineer and worked for RCA. Jacques is Professor Emeritus at CU in the Department of Electrical Engineering. “ *- http://www.colorado.edu/memorybox/jacquespankove.html Case 2: Ralph A. Logan・”Kressel began his career as a researcher in electronics and lasers at RCA Laboratories, which became Sarnoff Corporation and is now integrated into SRI as SRI International Sarnoff, where he devoted 24 years and attained the position of staff vice president.”, “Kressel also serves on the board of directors of Suniva, Inc., Telcordia Technologies, Inc., and WP Roaming Holdings SA (MACH). He is also Chairman of the Board of Trustees of Yeshiva University.”, “He holds 31 U.S. patents and has published more than 120 papers and three books.”- * http://www.sri.com/about/board/kressel.html

40. Findings “Cru node” scientist is not only classified as acted as “star scientist” (Zucker and Darby et al.), but also plays a role for inbounding, connecting the knowledge across the social group mostly identified as organization. And, “Cru node” patent and/or paper is under the average of his paper in the measurement of backward citation, in this sense, the (tacit / un-codified) knowledge would have a role for technical breakthrough.

42. University/Industry Collaboration had certain role for proceeding the technological development of Blue LED in Japan especially in 1980s.

43. Equivalent to prior research in qualitative case studies (Shimizu et al.)

44. Still couldn’t be ensuring the linkage between core prior technology and major invention via backward citation data only.

45. We must employ the method simultaneously for determining the prior technology for innovation, hybrid of survey, interview and literature survey and numerical approach. 19

46. Thanks. cd091007@g.hit-u.ac.jpyasushi.hara1982@gmail.com