충돌사고 유형에 따른 KHST의 승객거동에 관한 연구

윤영한(Youn Young-Han),구정서(Koo Jeong_Seo) 한국철도학회 1999 한국철도학회 학술발표대회논문집 Vol.- No.-

Safety of passengers in the Korean High Speed Train, KHST, was evaluated under the different accident scenarios. Preliminary occupant analysis has been performed based on the TGV-K train seat characteristics. The influence of the vehicle deceleration and passenger type, seating positions, effectiveness of compartmentalization have been evaluated in terms of occupant injury criteria. This study is the final result of the occupant analysis of KHST project at 1st stage 3rd year.

파라핀왁스 마스크의 적정온도와 안면 피부 개선 효과

윤영한 ( Young Han Youn ),김세희 ( Se Hee Kim ),김기영 ( Ki Young Kim ) 한국미용학회 2014 한국미용학회지 Vol.20 No.5

Paraffin wax is used for mask and bath in skin care and medical therapy. In this study, optimal temperature and skin improvement effect of paraffin wax such as stimulation of micro blood circulation and removal of sebum and keratin was investigated in women in the 20`s. Paraffin wax was spread first 5 layers and 10 layers at 50~55oC on inner wrist to observe potential temperature. Second 5 layers paraffin wax mask were applied twice/week in 4 weeks on dry facial skin of 7 women. Content of moisture and sebum were measured, and pore amount/size, skin surface temperature and skin improvement of keratin remove and texture were observed. In the result, potential temperature of paraffin wax was revealed in 5 layers at 52~53oC. After 8 times application of paraffin wax mask, moisture and sebum content were increased to 6.0% and to 12~19% before application. Face surface temperature were significantly increased to 3.7oC, and fine and large pores were significantly decreased to 234.6 pieces and to 69.7 pieces before application(p<0.05). Removal of keratin and crusts, improvement of skin texture and ton were observed after paraffin wax mask application. In conclusion, paraffin wax mask could have not only thermal effect but also deep cleansing effect and may be very useful in skin care.

[解說] 측면 충돌시 승객보호와 차체해석용 모델

윤영한(Young Han Youn) 한국자동차공학회 1992 오토저널 Vol.14 No.4

[Special Edition/Airbag]에어백의 효용성과 신뢰도

윤영한(Young Han Youn),홍승준(Seung Jun Hong) 한국자동차공학회 2003 오토저널 Vol.25 No.2

컴퓨터 시뮬레이션 기법을 이용한 고속전철 승객안전도 해석 및 평가

윤영한(Young-Han Youn),구정서(Jung-Suh Koo),이재완(Jae-Wan Lee) 한국철도학회 2003 철도저널 Vol.6 No.1

中等學校數學의 位相幾何에 관한 考察

한승국(Seung gook Han),윤영은(Young Eun Youn) 조선대학교 교과교육연구소 2007 敎科敎育硏究 Vol.28 No.1

Topology is rapidly developing field which applies not only to subsidiary field of mathematics, but also applies to astrophysics, computer science, information technology and molecular biology. It helps students to improve geometric sense and space perception so that they analyze the given subject quickly and perceive characteristic. I have a think about it s necessary to prepare paper since this ability is one of the prerequisites that human resources of modern society should acquire. As for theoretical background of topology, I would like to take a look at historical overview of topology in the second chapter of this paper and summarized basic concept of topology which is represented by metric, topology, continuous and homeomorphic. In the third chapter, I researched into current status of topology in secondary school and Euler s theorem treated as high class education material in the first grade of middle school. And I also presented brief summary of one writing along with Koonigsberg s bridge problem in relation with discrete mathematics of high school education. The trend of secondary school is reducing importance of topology, however research for better education involving easy understanding of students and practical use is constantly required since topology teaches students how to analyze mathematical circumstances in their life and helps to improve geometrical intuition.

사이클 수 증가에 따른 엔진밸브 및 시트인서트 착좌면 마모

김재희,전경진,홍재수,윤영한,Kim, Jae-Hak,Chun, Keyoung-Jin,Hong, Jae-Soo,Youn, Young-Han 한국자동차공학회 2007 한국 자동차공학회논문집 Vol.15 No.4

This study investigated the wear of the valve and seat insert seating faces. A tester, an exhaust valve and a seat insert were used. Test variables were cycle numbers ($2{\times}10^6,\;4{\times}10^6,\;6{\times}10^6\;and\;8{\times}10^6$) and Hz (10Hz and 25Hz). The other test conditions such as temperature ($350^{\circ}C$), fuel (LPG) and load (1960N) were fixed. The 10Hz tests indicated that the average Rmax of the valve increased at the rate of $7.76{\mu}m/10^6$ cycles starting from $29.42{\mu}m$ at the $2{\times}10^6$ cycles and that of the seat insert increased at the rate of $8.57{\mu}m/10^6$ cycles starting from $34.19{\mu}m$ at the $2{\times}10^6$ cycles. The 25Hz tests indicated that the average Rmax of the valve increased at the rate of $1.58{\mu}m/10^6$ cycles starting from $74.2{\mu}m$ at the $2{\times}10^6$ cycles and that of the seat insert increased at the rate of $1.25{\mu}m/10^6$ cycles starting from $83.95{\mu}m$ at the $2{\times}10^6$ cycles. The tribochemical reaction product covered the two seating faces, preventing the wear of the seating faces. As cycle numbers became greater, the average Rmax of the seating faces became greater, but the increase rate varied significantly depending on the Hz. The wear mechanism of the two faces was investigated through the tribochemical reaction.

Anti-Wrinkling Effect of Noni (Morinda citrifolia) by Antioxidant and Anti-Inflammatory Properties

최수철(Soo-Cheol Choi),윤영한(Young Han Youn) 인간식물환경학회 2020 인간식물환경학회지 Vol.23 No.2

Noni has been used for medicinal purposes for more than 2,000 years in South Pacific Polynesia, China and India, and has been heavily ingested as an extract for its excellent antioxidant and anti-inflammatory effects. However, a recent study found that the noni extract causes digestive disorders, kidney problems, and liver diseases, which made it necessary to use it for other purposes than as an extract. In this study, we want to evaluate the potential of noni as an anti-oxidant, anti-inflammatory and anti-wrinkling agent. Methods: Noni was freeze-dried, extracted in water, and concentrated. Skin cells were treated with the noni extract for 24 hrs and then were exposed to UVB (55 mJ/cm²). After 48 hrs of incubation, pro-inflammatory cytokine, elastase, MMP-1 and type-1 procollagen levels were measured by ELISA. Results: To find out the antioxidant effect of the noni extract, the DPPH and ABTS radical scavenging activity experiments were conducted and the noni extract showed 97.0 % and 92.0 % antioxidant efficacy at 200 μg/mL respectively. The noni extract (50 and 100 μg/mL) decreased IL-6 and TNF-α in RAW 264.7 cells induced by LPS in a concentration-dependent manner. In the RT-PCR experiment involving NO production, the noni extract (50 and 100 μg/mL) inhibited NO production by strongly inhibiting iNOS mRNA expression, and also inhibited the elevation of MMP-1 and elastases caused by UVB irradiation by 25.0 % and 7.0 % respectively. In addition, type-1 procollagen was elevated by 20.0 % by the noni extract treatment in HaCaT cells. Conclusion: The noni extract has photoprotective ability by reducing proinflammatory mediators, elastase and MMP-1 production, and elevation of collagen synthesis. Our findings suggest that the noni extract might be a good natural substance to protect against UVB-induced premature skin aging.

자기부상열차 경량시트 개발을 위한 최적화 기법에 관한 연구

김혜영(Kim Hye-young),윤영한(Youn Young-han),한완희(Han Wan-hee),김태현(Kim Tae-hyun),최세화(Choi Se-hwa) 한국철도학회 2009 한국철도학회 학술발표대회논문집 Vol.2009 No.11월

자기부상열차의 부품은 그 특성상 경량화가 필수적이다. 본 연구는 자기부상 열차의 시트를 경량화하는 경향시트를 설계하기위해 CAE를 적용하여 최적의 시트를 개발하는 방법론을 알아보았다. 유한요소 해석으로 열차 시트 프레임이 설계기준에 적용된 JIS E 7104를 만족하는지 판단하였다. Topology Optimization으로 최소한의 형상으로 힘의 분포를 견디는 구조물을 선정하였다. 이 최적화한 형상을 시트의 구조 설계에 적용하였다. In this study for Light Weight Seat of Maglev, the methodology was found to develop optimized seat using CAE. The seat frame must satisfy JIS E 7104 which was applied to judge the structural strengths. Then the seat frame was changed to the minimal shape to bear force distribution using Topology Optimization. This optimized frame was applied to the design of Maglev's seat structure.

자동차 교통사고 시 에어백에 의한 안면부 손상특성

이희영,이강현,이정훈,성실,강찬영,김호중,김상철,윤영한,Lee, Hee-Young,Lee, Kang-Hyun,Lee, Jung-Hun,Sung, Sil,Kang, Chan-Young,Kim, Ho-Jung,Kim, Sang-Chul,Youn, Young-Han 한국자동차안전학회 2016 자동차안전학회지 Vol.8 No.3

The purpose of this study is to evaluate the injury mechanism of facial injury related to an air-bag's deployment in occupant motor vehicle accident (MVA) by using Hospital Information System (HIS) and reconstruction program, based on the materials related to motor vehicle accidents. Among patients who visited the emergency department of Wonju Severance Christian Hospital due to motor vehicle accidents from August 2012 to February 2014, we collected data on patients with agreement for taking the damaged vehicle's photos. After obtaining the verbal consent from the patient, we asked about the cause of the accident, information on vehicle involved in the accident, and the location of car repair shop. The photos of the damaged vehicle were taken on the basis of front, rear, left side and right side. Damage to the vehicle was presented using the CDC code by analytical study of photo-images of the damaged vehicle, and a trauma score was used for medical examination of the severity of the patient's injury. Among the 309 patients with agreement for an investigation, thirty five (11.3 %) were the severe who had ISS over 15. And also, sixteen (5.2%) derived from the reconstructed data (maximum collision energy, maximum acceleration, delta V) by PC-Crash. As a result, ISS including the facial injuries was affected by the condition. It was high when the number of crash extent, the safety belt was not fastened, and the seating position of occupant and the direction of collision is same. For accurate analysis of the relationship between occupant injury and vehicle damage in MVAs, build-up of an in-depth database through carrying out various policies for motor vehicle accidents is necessary for sure.