저온분사 공정에서 알루미늄 분말의 산화가 임계 적층 속도에 미치는 영향

강기철,윤상훈,지율권,이창희,Kang, Ki-Cheol,Yoon, Sang-Hoon,Ji, Youl-Gwun,Lee, Chang-Hee 대한용접접합학회 2007 대한용접·접합학회지 Vol.25 No.4

In kinetic spraying process, the critical velocity is an important criterion which determines the deposition of a feedstock particle onto the substrate. In other studies, it was experimentally and numerically proven that the critical velocity is determined by the physical and mechanical properties and the state of materials such as initial temperature, size and the extent of oxidation. Compared to un-oxidized feedstock, oxidized feedstock required a greater kinetic energy of in-flight particle to break away oxide film during impact. The oxide film formed on the surface of particle and substrate is of a relatively higher brittleness and hardness than those of general metals. Because of its physical characteristics, the oxide significantly affected the deposition behavior and critical velocity. In this study, in order to investigate the effects of oxidation on the deposition behavior and critical velocity of feedstock, oxygen contents of Al feedstock were artificially controlled, individual particle impact tests were carried out and the velocities of in-flight Al feedstock was measured for a wide range of process gas conditions. As a result, as the oxygen contents of Al feedstock increased, the critical velocity increased.

탄소 나노튜브 알루미늄 복합재료 저온 분사 코팅의 적층 거동 및 특성

강기철,이창희,Kang, Ki-Cheol,Xiong, Yuming,Lee, Chang-Hee 대한용접접합학회 2008 대한용접·접합학회지 Vol.26 No.5

Carbon nanotube (CNT) aluminum composite coatings were built up through kinetic spraying process. Deposition behavior of CNT aluminum composite on an aluminum 1050 alloy substrate was analyzed based on deposition mechanism of kinetic spraying. The microstructure of CNT aluminum composite coating were observed and analyzed. Also, the electrical resistivity, bond strength and micro-hardness of the CNT aluminum composite coatings were measured and compared to kinetic sprayed aluminum coatings. The CNT aluminum composite coatings have a dense structure with low porosity. Compared to kinetic sprayed aluminum coating, the CNT aluminum composite coatings present lower electrical resistivity and higher micro-hardness due to high electrical conductivity and dispersion hardening effects of CNTs.

일본문화교육 전후 일본이해도 차이 연구 ― 경남지역 대학생을 중심으로 ―

강기철 ( Kang Gichul ) 한국일본어교육학회 2021 日本語敎育 Vol.- No.97

As a result of an empirical test of the difference in Japanese understanding before and after Japanese cultural education, the four areas of response samples(understanding of Japanese culture, understanding of Japanese politics and society, understanding of relations between Korea and Japan, understanding of historical issues between Korea and Japan) and the “friendliness,” “learning point,” and “necessity” of Japan were statistically significant results, confirming the necessity of Japanese cultural education. However, there was no significant difference in Japan, depending on gender and whether it was experienced in Japan. Based on these results, it is important to understand and educate Japanese culture with high interest, but efforts should be made to educate Japanese culture by enhancing the understanding of Japanese political society with relatively low interest. It is hoped that the results of the study will have a positive impact on the improvement of bilateral relations between Korea and Japan as a reference to understanding Japan.

만화가 고바야시 요시노리의 쇼와 천황에 대한 인식

강기철(Kang, GiChul) 동아시아일본학회 2024 일본문화연구 Vol.- No.89

Since the 1990s, Japanese society has become conservative in many areas, including politics, society, and culture. The same was true of Japanese comics, which are popular culture areas. In particular, Yoshinori Kobayashi has developed his conservative logic through comics activities and has had a great influence on Japanese society. Kobayashi has made great efforts to convey to the Japanese people the ideology of the Japanese emperor, which is the core of his conservative logic. The purpose of this study is to analyze the theory of the emperor expressed in Yoshinori Kobayashi comics. In this paper, data was collected & organized over the first and second rounds to analyze Kobayashi Yoshinoris comics, 『The Theory of Emperor Showa』. As a result of the analysis, it was possible to classify the subtopics as 1) the theory of imperial beautification 2) the theory of war responsibility 3) the theory of historical distortion. Then using the method of Roland Barts mythological theory, the final myth was derived that the Emperor is the national body of Japan and Japan itself.

일본 만화에 대한 인식과 연구 패러다임의 변화

강기철 ( Gi Chul Kang ) 가톨릭대학교 콘텐츠산업과 문화정책연구소 2009 디지털콘텐츠와 문화정책 Vol.4 No.-

SCTP 기술을 이용한 효율적인 DLNA 미디어 스트리밍 환경 구축에 관한 연구

강기철(Ki Cheol Kang),김대진(Dae Jin Kim) 한국방송·미디어공학회 2011 한국방송공학회 학술발표대회 논문집 Vol.2011 No.7

최근의 스마트 폰 및 스마트 TV 열풍은 사용자의 가정 내 무선 멀티미디어 네트워킹 서비스에 대한 욕구를 증가시켰고, 2004년 출범한 DLNA 기술의 보급을 촉진시켰다. 그러나 무선 네트워크 환경의 불안정성과 기존 TCP/UDP 데이터 전송 기술이 가진 한계로 인해 DLNA를 통한 고화질의 멀티미디어 데이터 서비스에는 제한이 존재했던 것이 사실이다. 이에 본 논문은 이러한 문제의 해결 방안을 모색하고자 DLNA 디바이스인 DMR과 DMS 간 SCTP 멀티 스트리밍 기술을 이용한 미디어 데이터 스트리밍 방법에 관해 연구하고, 이를 구현하였다. 전송된 스트림은 여러 조각으로 나뉘어 동일한 양의 버퍼에 복사되고, 버퍼 각각에 스트림 번호를 부여하여 SCTP 멀티 스트리밍 기법을 이용해 전송함으로써 더욱 신뢰성 있는 미디어 데이터의 스트리밍이 가능하였다.

고속 화염 용사를 통하여 형성된 다중벽 탄소 나노튜브 알루미늄 복합소재 코팅의 특성 평가

강기철(Kicheol Kang),박형권(Hyungkwon Park),이창희(Changhee Lee) 한국표면공학회 2012 한국표면공학회지 Vol.45 No.1

Multi-walled carbon nanotube (MWCNT) aluminum composite powders were deposited to form coatings using a high velocity oxygen fuel (HVOF) spraying process. High thermal energy and contact with atmospheric oxygen were supplied as the MWCNT aluminum composite particles were exposed to a gas flow field at high temperature (~3.0 × 10<SUP>3</SUP> K) during HVOF spraying. As a result, the particles underwent full or partial melting and rapid solidification due to the high thermal energy, and the exposure to oxygen induced the interfacial reaction of MWCNTs within the particle. The electrical and mechanical properties of MWCNT aluminum composite coatings were evaluated based on microstructure analysis. Electrical resistivity, elastic modulus, and micro-hardness, of the MWCNT aluminum composite coatings were higher than those of pure aluminum coating. The contribution of MWCNTs to the aluminum matrix can be attributed to their high electrical conductivity, dispersion hardening and anchoring effects. The relationship among the properties and the interaction of the MWCNTs with the aluminum matrix is discussed.

한국 대학생의 한일관계개선의 결정요인 ― 경남지역 대학생을 중심으로 ―

강기철 ( Kang Gichul ) 한국일본어교육학회 2021 日本語敎育 Vol.- No.95

The purpose of this study is to analyze the determinants for the improvement of Korea-Japan relations among Korean university students. Multiple Regression Analysis was conducted by setting variables such as understanding of Japanese culture, Japanese political society, Korean-Japanese historical issues, and the improvement of Korea-Japan relations. As a result of the analysis, understanding of Japanese culture and Korean-Japanese history issues had a statistically significant influence on the determinants of improving relations between Korea and Japan, but understanding of Japanese political society did not show a meaningful statical result. The subsequent research tasks of this study are as follows. First, there is a need for a sufficient analysis and research on why understanding of Japanese political society did not affect Korean university students. Second, it is necessary to collect and analyze from mid-to long-term data more than over 5 years. Third, data and analysis.

체외수정시술 후 발생한 병합임신

강기철(Gi Chul Kang),이장용(Jang Yong Lee),배유영(Yu Young Bae),김대화(Dae Hwa Kim),기광수(Kwang Soo Kee),임헌정(Hun Jung Im) 대한산부인과학회 1999 Obstetrics & Gynecology Science Vol.42 No.9

Heterotopic pregnancy, simultaneous intrauterine and extrauterine pregnancy, is an extremely rare case. The incidence of heterotopic pregnancy was about 1 to 30,000 pregnancies, but it has increased after wider use of assisted reproductive technology. The rising incidence presents a serious problem as the diagnosis of this potentially fatal condition is often missed. Careful pelvic examination combined with serial β-hCG determinations, and transvaginal sonography to evaluate the adnexal region are necessary prerequisites for early diagnosis. We report a case of heterotopic pregnancy following in vitro fertilization and embryo transfer(IVF-ET) with a brief review of literature.

동진강 유역 비점오염원 관리지역 선정을 위한 수질 변화 특성 연구

강기철 ( Ki-cheol Kang ),김재승 ( Jae-seung Kim ),원찬희 ( Chan-hee Won ) 한국환경기술학회 2013 한국환경기술학회지 Vol.14 No.5

본 연구에서는 동진강 유역 4대하천인 동진강, 정읍천, 고부천, 원평천 수계의 수질변화 특성을 파악하였다. 우선 수질측정망 측정지점을 기준으로 해당유역의 지목별 분포 특성을 파악하였고, 해당유역의 배출부하량을 산출하였다. 이들을 토대로 측정망 수질자료를 활용, 수질변화를 분석하였다. BOD의 경우 대부분 농번기인 5~6월이 연평균보다 20~60 % 이상 높게 나타났으며, TN의 경우 건기인 11~2월에 높게 나타났다. 고부천의 경우 측정망 최상류지점인 GB1 유역이 수계 수질에 가장 큰 영향을 미치는 것으로 나타났다. 원평천 WP1 유역의 경우 농경지 비율이 낮은 데도 불구하고 농번기의 BOD농도가 연평균 보다 60 %정도 높아 이 유역의 농경지 관리가 요구된다. GB1 및 WP1 유역의 경우 비점오염원 관리를 위해 유역을 좀 더 세분하여 모니터링 할 필요가 있다. 정읍천 및 동진강의 경우 수질에 영향을 많이 미치는 유역은 CW(천원천) 유역과 JE4 유역으로 나타났다. 동진강 유역의 BOD는 농경지가 주 요인이며, 농번기의 농경지 관리가 요구된다. BOD저감을 위한 비점오염원 관리가 필요한 지역은 고부천 GB1 유역, 원평천 WP1 유역, 정읍천 CW 유역이다. TN의 경우 축산폐수 및 생활하수 등이 주 요인이며, 지속적인 관리가 요구되는 지역은 고부천유역과 정읍천의 JE4 유역이다. In four streams of Dongjin River basin, consisted of mainstream Dongjin-River, Jungeup-cheon, Gobu-cheon, Wonpyeong-cheon, changes characteristics of water quality were researched. Based on the monitoring points of water quality monitoring newtwork, the effluent loads was calculated, and the water quality change was analysed. BOD was 20-60 % higher in busy farming season from May to June than in the annual average. TN was higher in the dry season from December to February than in the annual average. In Gobu-cheon basin, GB1 basin was shown in highest effect of water quality deterioration. In Wonpyeong-cheon basin, WP1 basin was shown that BOD was 60 % higher in the farming season than in the annual average. GB1 and WP1 basins is necessary for monitoring non-point source management specifically In Dongjin-river and Jeongeup-cheon basin, CW(Cheonwon-cheon) and JE4 basins was shown in highest effect of water quality deterioration. In Dongjin-river basin, agricultural land is a major cause of deterioration of BOD. So there is a need to manage agricultural land of the busy farming season. For BOD reduction, non-point source management of GB1, WP1 and CW basins is needed. Livestock wastewater and sewage is the main cause of deterioration of TN. For TN reduction, non-point source management of Gobu-cheon and JE4 basins is needed.