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Choi, Junsub;Moon, Taeseok;Choi, Jongin;Park, Sanghyeon;Kim, Hansol;Huh, Hwanil
- Journal of the Korean Society for Aeronautical & Space Sciences
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- v.46 no.8
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- pp.662-670
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- 2018
The altitude compensation nozzle is a nozzle designed for optimum performance at all altitudes. A method of improving the specific impulse of the space launch vehicle is a method of improving the characteristic exhaust velocity which is a characteristic of the combustion chamber and a method of improving the thrust coefficient which is a characteristic of the nozzle. The altitude compensation nozzle enables improvement of the performance of the space launch vehicle by improving the nozzle performance for the same combustor. Research on altitude compensation nozzles has been actively carried out in the DLR in Germany and is being carried out in advanced countries such as the US, Russia, UK, Australia and Japan. In this paper, the technology trends and patent trends of altitude compensation nozzles are investigated and summarized. Based on this, the technical trends of altitude compensation nozzles is grasped and utilized as basic data for the study on the performance improvement of a launch vehicle.
https://doi.org/10.5139/JKSAS.2018.46.8.662 인용 PDF KSCI

Kim, Kirl;Chun, Joung-Yoon;Shin, Dong-Bin;Lim, Si-Yeong
- Journal of Korean Society for Geospatial Information Science
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- v.19 no.1
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- pp.53-61
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- 2011
The purpose of this study is to suggest development directions and elicit future research themes of U-City and future city by identifying the research trends of U-City theses. For this, meta-keywords were elicited based on the theses of U-City and future city published from mid 1990s to 2010. Centered on the meta-keywords, temporal keyword analysis was performed to compare the research trends of U-City and future city theses in Korea and oversea. The results show that most of U-City and future theses in Korea and oversea mainly dealt with technology. U-City theses in Korea have a tendency to research technology, methodology, service, planning and management in order from the early beginning. However, the U-City and future theses in oversea have a tendency to continuously study U-City applications to city through the model based on the technology and methodology. Therefore, the U-City research in Korea should focus on aspects of urban regeneration, urban scale, and so on. That is to say, the research in near future is required to apply the U-City to various urban themes.
PDF KSCI

Ko, Ungdai;Seo, Inho;Lee, Juyoung;Jeong, Hyunjae
- Journal of Space Technology and Applications
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- v.1 no.3
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- pp.337-355
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- 2021
This paper is made to suggest a future strategy for the Korean High Resolution Wide Swath Synthetic Aperture Radar (HRWS SAR) satellite development by surveying the current trends for the SAR satellite technologies. From the survey, the latest SAR technology trends are revealed of using Digital Beam-Forming (DBF), SCan-On-Receive (SCORE), Displaced Phase Center Antenna (DPCA), interferometry, and polarimetry for exploiting the SAR imagery. Based on the latest SAR technology trends and the foreign HRWS SAR development cases, the strategy for the future HRWS Korean SAR satellite development is suggested to develop the DPCA and SCORE technologies by using the KOrea Multi-Purpose SATellite-6 (KOMPSAT-6) which is going to launch in a few years, and consequently to develop the HRWS SAR satellites which can monitor the whole Earth at weekly intervals.
https://doi.org/10.52912/jsta.2021.1.3.337 인용 PDF