The Defense Systems Information Analysis Center (DSIAC) was asked to search available databases to identify the top global researchers and organizations in low observable (LO) material science. DSIAC searched multiple literature databases, including Elsevier’s Scopus database and Clarivate’s Derwent Innovations and Web of Science (WoS) databases, to provide information on the publications, number of citations, and patents awarded in LO material science technology and research development. Lists of the top global researchers and affiliations were compiled based on patents awarded and Scopus and WoS database publications and citations.
1.0 Introduction
The Defense Systems Information Analysis Center (DSIAC) completed literature searches for publications and patent information on low observable (LO) material science technology via the Scopus database and Clarivate’s Derwent Innovation and Web of Science (WoS) databases. DSIAC used a combination of the following search terms:
- stealth AND military AND (material OR coating)
- “low observable” AND (infrared OR coating)
- “low observable” AND (materials OR design OR shaping)
- stealth AND (materials OR design OR infrared)
The searches were limited to the past 3 years so that the results would reflect the most recent research. The results across all searches are compiled in Table 1.
Table 1: Top Researchers Across All Searches
| Researcher | No. of Patents Granted | No. of Patents Pending | No. of Scopus Publications | No. of WoS Publications |
| Cheng, Hai-feng | 13 | — | — | — |
| Liu, Hai-tao | 12 | — | — | — |
| Pottier, Agnes | 10 | — | — | — |
| Levy, Laurent | 10 | — | — | — |
| Meyre, Marie-Edith | 10 | — | — | — |
| Cao, Tun | 10 | 31 | — | — |
| Zhou, Yong-jiang | 10 | — | — | — |
| Cui, Hua-gang | 9 | — | — | — |
| Yao, Jun-feng | 8 | — | — | — |
| Zhang, Chao-yang | 8 | — | — | — |
| Qu, Shaobo | — | — | 11 | 12 |
| Wang, Jia-fu | — | — | 9 | 11 |
| Pang, Yongqiang | — | — | 8 | 10 |
| Zhang, Anxue | — | — | 8 | — |
| Baskey, Himangshu Bhusan | — | — | 7 | — |
| Brookner, Eli | — | — | 7 | — |
| Chen, Juan | — | — | 7 | — |
| Jiang, Tian | — | — | 7 | — |
| Singh, Dharmendar Kumar | — | — | 7 | 10 |
| Liu, Ruihuang | — | — | 7 | — |
| Panwar, Ravi | — | — | 7 | — |
| Xu, Guoyue | — | — | 7 | — |
| Zhang, Jieqiu | — | — | 7 | — |
| Zhao, Dapeng | — | — | 7 | — |
| Huang, Jun | — | — | 7 | — |
| Li, Xiong | — | — | — | 12 |
| Li, Guanyong | — | — | — | 10 |
| Zhang, Yin | — | — | — | 9 |
| Liu, Yujia | — | — | — | 9 |
| Wang, Jian-wei | — | — | — | 9 |
| Zhang, Jing | — | — | — | 9 |
| Zhou, Jian-jing | — | 17 | — | — |
| Yamashita, Shigeyuki | — | 17 | — | — |
| Junkers, Eric P. | — | 15 | — | — |
| Junkers, John K. | — | 14 | — | — |
| Wang, Fei | — | 14 | — | — |
| Shi, Chen-guang | — | 13 | — | — |
| Zhang, Xiaoxing | — | 12 | — | — |
| Li, Hai-lin | — | 12 | — | — |
| Wang, Feng | — | 12 | — | — |
Note: WoS = Web of Science.
The following results are provided in Sections 2.1 and 2.2:
- Top researchers and organizations based on the number of patents awarded and pending in LO material science research (Section 2.1).
- Research and patent trends among top countries performing LO material science research (Section 2.1).
- Top researchers and organizations based on the number of publications and citations found in Scopus (Section 2.2).
- Top researchers and organizations found in the WoS database (Section 2.2).
2.0 Top Researchers / Organizations Based on Patents
The Derwent Innovation database, part of Clarivate Analytics, was used to search for global researchers in LO material science based on the number of granted (awarded) patents. Searches were performed using the following terms:
- stealth AND military AND (material OR coating)
- “low observable” AND (infrared OR coating)
- “low observable” AND (materials OR design OR shaping)
- stealth AND (materials OR design OR infrared)
A spreadsheet containing patent information for the top results found in Derwent Innovations was exported and delivered to the inquirer for further review.
2.1 Patents Granted
The search parameters included patents granted in 2016 to the present and alive and indeterminate patents. The total number of hits was 733, and 100 (i.e., 14%) of the patents are from the top organizations (shown in Table 2).
Table 2 lists the top organizations based on patents granted, with the top researcher from the associated organization. The researchers identified in bold in Table 2 can also be found in Table 3, which lists the top researchers, based on patents granted, in descending order. The top researchers hold 100 patents, or 14% of the total patents granted.
Table 2: Top Organizations Based on Patents Granted
| Organization | No. of Patents Granted per Organization |
Top Researcher(s) |
No. of Patents per Researcher |
| Dalian University of Technology | 15 | Cao, Tun | 10 |
| National University of Defense Technology, China | 15 | Cheng, Hai-feng | 13 |
| Nanjing University of Aeronautics and Astronautics | 13 | Zhou, Jian-jing | 6 |
| Nanobiotix | 10 | Pottier, Agnes | 10 |
| Harbin Institute of Technology | 8 | Li, Long-qiu | 2 |
| University of Electronic Science and Technology of China | 8 | Deng, Long-jiang | 3 |
| Massachusetts Institute of Technology | 8 | Wardle, Brian L. | 3 |
| Northwestern Polytechnical University, China | 8 | Zhang, Qun | 4 |
| Hnegyang Tellhow Communication Vehicles Co., Ltd. | 8 | Cui, Hua-gang | 9 |
| Shandong University | 7 | Liu, Jiu-rong | 4 |
Table 3: Top Researchers Based on Patents Granted
| Researcher | No. of Patents Granted | Affiliation |
| Cheng, Hai-feng | 13 | National University of Defense Technology |
| Liu, Hai-tao | 12 | National University of Defense Technology |
| Pottier, Agnes | 10 | Nanobiotix Co., Ltd. |
| Levy, Laurent | 10 | Nanobiotix Co., Ltd. |
| Meyre, Marie-Edith | 10 | Nanobiotix Co., Ltd. |
| Cao, Tun | 10 | Dalian University of Technology |
| Zhou, Yong-jiang | 10 | National University of Defense Technology |
| Cui, Hua-gang | 9 | Hengyang Tellhow Communication Vehicles Co., Ltd. |
| Yao, Jun-feng | 8 | Shanghai Smartee Denti-Technology Co., Ltd. |
| Zhang, Chao-yang | 8 | National University of Defense Technology |
2.2 Patent Trends by Top Countries
According to the Derwent database, China, the United States, and Japan are the top patent holders in LO research. Based on data from Derwent, the number of patents issued in each country from 2016 to the present has increased each year, suggesting LO research is on the rise (shown in Figure 1).
Figure 1: Graph of U.S., Chinese, and Japanese Patent Trends.
2.3 Patents Pending
The top researchers and their affiliations based on the number of pending LO patent applications without grants are shown in Table 4. Using the same terms as before, the search was limited to alive and indeterminate patents from 2016 to the present. Indeterminate patents were included because it was unclear whether they were dead or alive.
Table 4: Top Researchers Based on Pending Patents
| Researcher | No. of Pending Patents | Affiliation |
| Cao, Tun | 31 | Dalian University of Technology |
| Zhou, Jian-jing | 17 | Nanjing University of Aeronautics and Astronautics |
| Yamashita, Shigeyuki | 17 | Lintec, Corporated |
| Junkers, Eric P. | 15 | Hytorc Division, UNEX Corporation |
| Junkers, John K. | 14 | Hytorc Division, UNEX Corporation |
| Wang, Fei | 14 | Nanjing University of Aeronautics and Astronautics |
| Shi, Chen-guang | 13 | Nanjing University of Aeronautics and Astronautics |
| Zhang, Xiaoxing | 12 | Hytorc Division, UNEX Corporation |
| Li, Hai-lin | 12 | Nanjing University of Aeronautics and Astronautics |
| Wang, Feng | 12 | Hengyang Tellhow Communication Vehicles Co. Ltd.
Nanjing University of Aeronautics and Astronautics |
3.0 Top Researchers / Organizations Based on Publications and Citations
3.1 Scopus Search Results
DSIAC also used Scopus, a literature database, to search for researchers and organizations working in hypersonics and patents related to hypersonics. Scopus is the largest curated abstract and citation database of peer-reviewed literature, containing over 71 million records, 23,000 peer-reviewed journals, and more than 166,000 books. Scopus uses sophisticated search tools that can search by document, author, or affiliation and can refine results by source type, year, language, author, affiliation, and more. As with other search engines, Boolean logic can narrow the number of citations to more relevant results. Scopus also contains hundreds of thousands of engineering conference papers not covered in alternative databases [1].
Using the same search terms as in the patent search, the Scopus search was also limited to publications from 2016 to the present. The top organizations are shown in Table 5, and the top researchers are shown in Table 6. The rankings are based on number of publications and citations per organization/researcher. The h‑index metric is also included as an attempt to measure the productivity and citation impact of the publications of the researchers. The h‑index is based on an author’s number of publications and citations to provide an estimate of the importance and impact of his/her research contributions. The h-index means a researcher has index h if h of his/her publications have at least h citations each. For example, an h-index of 15 means that 15 of the author’s publications have received at least 15 citations each. The higher the h-index, the more credible the research.
Table 5 identifies the top organizations based on the number of publications, with the top researcher(s) from the associated organization. Ten of the top researchers identified in bold in Table 5 are can also be found in Table 6, which identifies top researchers based on number of publications.
Table 5: Top Organizations Based on the Number of Publications
| Organization | No. of Documents | Top Researcher(s) | No. of Documents |
No. of Citations |
h-Index |
| Ministry of Education China | 43 | Cao, Weiping | 2 | 32 | 9 |
| Northwestern Polytechnical University | 39 | Zhou, Li | 5 | 16 | 7 |
| Air Force Engineering University, China | 37 | Qu, Shaobo | 11 | 47 | 39 |
| Wang, Jiafu | 9 | 47 | 32 | ||
| Pang, Yongqiang | 8 | 47 | 18 | ||
| Zhang, Jieqiu | 7 | 41 | 21 | ||
| National University of Defense Technology | 30 | Liu, Ruihuang | 7 | 3 | 1 |
| Zhao, Dapeng | 7 | 19 | 7 | ||
| Nanjing University of Aeronautics and Astronautics | 27 | Jiang, Tian | 7 | 68 | 22 |
| Xu, Guoyue | 7 | 17 | 22 | ||
| Chinese Academy of Sciences | 26 | Luo, Xiangang | 6 | 45 | 51 |
| Beihang University | 22 | Huang, Jun | 7 | 6 | 10 |
| Beijing Institute of Technology | 22 | Fang, Daining | 3 | 24 | 43 |
| Xi’an Jiaotong University | 19 | Zhang, Anxue | 8 | 5 | 18 |
| Harbin Institute of Technology | 19 | Wen, Guangwu | 3 | 11 | 23 |
Table 6: Top Researchers Based on Scopus Publications and Citations
| Researcher | Affiliation | No. of Documents | No. of Citations | h-Index |
| Qu, Shaobo | Air Force Engineering University, China | 11 | 47 | 39 |
| Wang, Jiafu | Air Force Engineering University, China | 9 | 47 | 32 |
| Pang, Yongqiang | Air Force Engineering University, China & Xi’an Jiaotong University, China | 8 | 47 | 18 |
| Zhang, Anxue | Xi’an Jiaotong University, China | 8 | 5 | 18 |
| Baskey, Himangshu Bhusan | Indian Institute of Technology | 7 | 24 | 9 |
| Brookner, Eli | Raytheon | 7 | 9 | 14 |
| Chen, Juan | Xi’an Jiaotong University, China | 7 | 4 | 9 |
| Jiang, Tian | Nanjing University, China | 7 | 68 | 22 |
| Singh, Dharmendar Kumar | Indian Institute of Technology | 7 | 45 | 25 |
| Liu, Ruihuang | National University of Defense Technology, China | 7 | 3 | 1 |
| Panwar, Ravi | Pandit Dwarka Prasad Mishra Indian Institute of Information Technology, Design and Manufacturing, India | 7 | 57 | 9 |
| Xu, Guoyue | Nanjing University, China | 7 | 17 | 22 |
| Zhang, Jieqiu | Air Force Engineering University, China | 7 | 41 | 21 |
| Zhao, Dapeng | National University of Defense Technology, China | 7 | 19 | 7 |
| Huang, Jun | Beihang University, China | 7 | 6 | 10 |
3.2 WoS Search Results
WoS provides access to research literature linked to a rigorously selected core of journals, ensuring a unique combination of discovery through captured metadata and citation connections. The WoS Core Collection provides over one billion cited reference connections indexed from high-quality, peer-reviewed journals, books, and proceedings from 1900 to the present.
WoS was the final database used by DSIAC to search for top global researchers and organizations in hypersonics. The top researchers and organizations identified via the WoS search are shown in Tables 7 and 8, respectively. The same search terms were applied to the WoS search, with this search also being limited to publications from 2016 to the present.
Table 7: Top Researchers in WoS
| Researcher | Affiliation | No. of Documents |
| Li, Xiong | Chinese Academy of Sciences | 12 |
| Qu, Shaobo | Air Force Engineering University, China | 12 |
| Wang, Jia-Fu | Air Force Engineering University, China | 11 |
| Pang, Yongqiang | Air Force Engineering University, China | 10 |
| Singh, Dharmendra | Indian Institute of Technology, Roorkee, India | 10 |
| Li, Guanyong | Chinese Academy of Sciences | 10 |
| Zhang, Yin | Nanjing University, School of Information Engineering | 9 |
| Liu, Yujia | Chinese Academy of Sciences | 9 |
| Wang, Jian-wei | Chinese Academy of Sciences | 9 |
| Zhang, Jing | Chinese Academy of Sciences | 9 |
Table 8: Top Organizations in WoS
| Organization | No. of Documents | No. of Citations |
| Chinese Academy of Sciences | 36 | 238 |
| Air Force Engineering University | 23 | 108 |
| Northwestern Polytechnical University | 21 | 307 |
| Centre National de La Recherche Scientifique, France | 21 | 113 |
| Indian Institute of Technology System | 20 | 141 |
| Nanjing University of Aeronautics Astronautics | 19 | 56 |
| Xi’an Jiaotong University | 16 | 83 |
| Zhejiang University | 16 | 284 |
| Beijing Institute of Technology | 15 | 145 |
| Monashi University | 15 | 127 |
| National University of Defense Technology, China | 15 | 82 |
3.3 Search Results Analysis
There were two different metrics used to search top global researchers in LO material science research—the number of patents and the number of publications and citations. When the searches were compared, zero organizations appeared in the search results of each database. The following organizations appeared in the search results of at least two of the databases:
- Harbin Institute of Technology, China
- Air Force Engineering University, China
- Chinese Academy of Sciences
- Beijing Institute of Technology
- Xi’an Jiaotong University
There were no researchers that appeared in all our database search results. Two researchers appeared in the search results of at least two of the databases, Tun Cao and Dharmendra Singh. Tun Cao is affiliated with Dalian University of Technology and has been awarded 10 patents. He currently has 31 pending patents, suggesting he is a key researcher in current LO material science. Dharmendra Singh is affiliated with the Indian Institute of Technology and had some of the top publications in Scopus and Derwent databases.
A potential point of interest is that even after multiple rounds of filtering search results, many medical patents and publications were in the final search results. The technology being used in medical applications may or may not prove applicable to LO material science applications being sought in the military. However, the medical use of LO materials may be worth exploring.
References
[1] Elsevier. “Scopus. An Eye on Global Research: 5,000 Publishers. Over 71M Records and 23,700 Titles.” https://www.elsevier.com/solutions/scopus/how-scopus-works, 24 October 2019.