항공기용 복합소재 인증 고찰

양용만,윤범수,전승목,이승근,백운율,오만석,Yong-Man Yang,Bum-Soo Yoon,Seung-Mok Jeon,Seung-Ken Lee,Un-Ryul Baek,Man-Seok Oh 한국복합재료학회 2023 Composites research Vol.36 No.5

Composite materials used in aircraft must be certified using approved materials to ensure the the airworthiness of the aircraft. Certification is carried out by verifying the physical properties and processes of the materials, and producing material and process specifications. The composite material certification system in ROK(Republic of Korea) has been established through the MOLIT(Ministry of Land, Infrastructure and Transport) pilot certification project for aircraft composite materials. Currently, the KIAST(Korea Institute of Aviation Safety Technology) operates and manages the certification and shared data system. This study identifies realm for improvement in the established certification system for aircraft composite materials based on empirical evidence and aims to propose measures for the certification and industrial promotion of domestically produced aircraft composite materials.

모바일 환경 기반 비디오 선택 및 요약 서비스 시스템에 관한 연구

양선우(Sun Woo Yang),배빛나라(Beetnara Bae),노용만(Yong Man Ro) 한국정보과학회 2003 한국정보과학회 학술발표논문집 Vol.30 No.2Ⅱ

본 논문에서는 모바일 환경에서, 사용자의 상황정보와 개인적 선호도 정보를 고려하여 사용자에게 적합한 영화를 선택, 추천하고, 선택된 영화의 요약(Summary)을 서비스 할 수 있는 시스템을 제안한다. 제안된 시스템은 사용자가 이동하는 상황에 따라 변하는 위치, 시간 정보와 개인적 선호도인 영화장르 정보에 기반한 영화선택 서비스를 제공하고, 선택된 영화 콘텐츠의 요약을 MPEG-7 메타데이터로 기술하고, 이를 이용해 요약을 효과적으로 소모할 수 있게 한다. 제안된 시스템을 통해, 모바일 환경 기반 영화 선택 및 요약 서비스 시스템(Mobile Environment-Based Movie Selection and Summary Service System)을 실현하고, 그 효용성을 입증하였다.

직무스트레스에 따른 조직몰입과 직무만족

양춘희(Chun Hee Yang),권용만(Yong Man Kwon) 한국관광연구학회 2005 관광연구저널 Vol.19 No.3

The results of the analysis can be summarized at the following: First, the influence of job satisfaction varies factors in job stress expect participation in decision-making at full-time employees, but only two factors `task characteristic, role conflict` at part-time employees. Second, factors in job stress with role conflict, leadership style showed significant difference depending on employment mode. Therefore, full-time employment showed the increase task level and trust in organization and part-time employment showed increase task and participation in decision-making implying the decrease of job stress through the endowment organizational involvement. Third, the influence of job stress depending on the employment mode showed no significant difference.

소형 복합재 태양광 무인기 윙 리딩에지스킨 모델 비교 연구

양용만,김용하,김종환,김영인,이수용,Yang, Yong-Man,Kim, Yong-Ha,Kim, Jong-Hwan,Kim, Young-In,Lee, Soo-Yong 한국전산구조공학회 2017 한국전산구조공학회논문집 Vol.30 No.5

본 연구에서의 날개 앞전은 날개의 공기역학적인 기능뿐만 아니라 조류 등의 외부의 손상을 줄 수 있는 것으로부터 날개 내부 구성요소를 보호하고 안전한 항공기 운항을 위한 반드시 필요한 구조 요소이다. 복합재 무인기의 날개 경량화를 위한 최적의 제작 모델을 비교 검토하였다. MSC. Patran/Nastran을 이용한 유한요소해석을 통하여 비틀림 하중의 변위 형상을 비교 확인하였으며, 각 모델들의 비틀림 강도 실험을 통하여 적층 유형, 두께 변화 및 형상 적용에 따른 경량화 성능 개선을 확인하므로써 소형 복합재 무인기 최적의 경량화 날개 앞전스킨의 형태를 제시하였다. The wing leading edge skin in this research is an essential structural factor for improving wings' aeromechanical functions, protecting the interior elements of the wings from external damage including birds, and navigating planes safely. The study compared and reviewed models manufactured for optimal light-weight wings of composite UAVs. It compared and investigated displacement forms of torsion loads through finite element analysis using MSC. Patran/Nastran. By confirming the improvement of light-weighting performance according to lamination type, thickness change and shape through torsion strength tests of each model, the research suggested the optimal light-weight wing leading edge skin for small composite UAVs.

삼차원 유한요소법을 이용한 대퇴골두 무혈성괴사의 역학에 관한 정량적 연구

양진원 ( Yang Jin Won ),구경회 ( Gu Gyeong Hoe ),이민철 ( Lee Min Cheol ),하용찬 ( Ha Yong Chan ),김강일 ( Kim Gang Il ),황선철 ( Hwang Seon Cheol ),이상진 ( Lee Sang Jin ),전만수 ( Jeon Man Su ) 대한고관절학회 2000 Hip and Pelvis Vol.12 No.3

치료계획 시스템을 이용한 Varian Standard Couch 모델링의 유용성 평가

양용모,송용민,김진만,최지민,최병기,Yang, yong mo,Song, yong min,Kim, jin man,Choi, ji min,Choi, byeung gi 대한방사선치료학회 2016 대한방사선치료학회지 Vol.28 No.1

목 적 : 방사선 치료 시 Carbon Fiber Couch에 의한 감약이 일어난다. 본 연구에서는 치료계획 시스템(Treatment Planning System: TPS)을 이용해 Varian사의 Varian Standard Couch(VSC)를 모델링 하여 유용성을 평가하고자 한다. 대상 및 방법 : 선형가속기(Clinac IX, VARIAN, USA)의 CBCT(Cone Beam Computed Tomography)를 이용하여 VSC의3가지 조건Side Rail Out Grid(SROG), Side Rail InGrid(SRIG), Side Rail In OutSpine Down Bar(SRIOS)로 스캔 한 후 TPS(Pinnacle9.8, Philips, USA)로 전송하여 Side Rail, Side Bar Upper, Side Bar Lower, Spine Down Bar를 Automatic Contouring하여 모델링 하였다. 전산화 단층촬영(Light Speed RT 16, GE, USA)으로 스캔 한 Cheese Phantom(Middelton, USA) 을 TPS로 전송하여 모델링 한 VSC를 적용하였다. 측정 점은 Cheese Phantom내의 Ion Chamber(A1SL, Standard imaging, USA)이며 Isocenter에 위치시켜 Energy(4, 10MV), Gantry Angle($5^{\circ}$간격으로 측정), Field Size($3{\times}3cm^2$, $10{\times}10cm^2$)에 변화를 주어 각 100MU의 동일한 조건에서 얻은 계산 값과 측정값을 비교하였으며 Side Bar Upper에 의한 감약을 비교하기 위해 SRIG조건에서 $127^{\circ}$를 포함하였다. 결 과 : CBCT를 이용해 얻은 VSC의 Density를 TPS에서 확인한 결과 $0.9g/cm^3$였으며 Spine Down Bar의 경우 $0.7g/cm^3$로 나타났다.Side Rail, Side Bar Upper, Side Bar Lower, Spine Down Bar에서 각 17.49%, 16.49%, 8.54%, 7.59%의 감약이 일어났으며모델링의 정확성을 평가하기 위해 계산 값과 측정값을 비교한 결과 평균 1.13%의 오차가 보였으며 Spine Down Bar를 지나는 $170^{\circ}beam$에서 1.98%로 가장 많은오차를 보였다. 결 론 : TPS이용해 모델링 한 VSC의 유용성을 평가하기 위해계산 값과 측정값을 비교한 결과 최대1.98%의 오차를 보였다. 방사선 치료계획 시 VSC를 모델링 하여 적용한다면선량에 대한 예측이 가능해 더욱 정확한 치료를 하는데 도움이 될 것으로 사료된다. Purpose : When a radiation treatment, there is an attenuation by Carbon Fiber Couch. In this study, we tried to evaluate the usability of the Varian Standard Couch(VSC) by modeling with Treatment Planning System (TPS) Materials and Methods : VSC was scanned by CBCT(Cone Beam Computed Tomography) of the Linac(Clinac IX, VARIAN, USA), following the three conditions of VSC, Side Rail OutGrid(SROG), Side Rail InGrid(SRIG), Side Rail In OutSpine Down Bar(SRIOS). After scan, the data was transferred to TPS and modeled by contouring Side Rail, Side Bar Upper, Side Bar Lower, Spine Down Bar automatically. We scanned the Cheese Phantom(Middelton, USA) using Computed Tomography(Light Speed RT 16, GE, USA) and transfer the data to TPS, and apply VSC modeled previously with TPS to it. Dose was measured at the isocenter of Ion Chamber(A1SL, Standard imaging, USA) in Cheese Phantom using 4 and 10 MV radiation for every $5^{\circ}$ gantry angle in a different filed size($3{\times}3cm^2$, $10{\times}10cm^2$) without any change of MU(=100), and then we compared the calculated dose and measured dose. Also we included dose at the $127^{\circ}$ in SRIG to compare the attenuation by Side Bar Upper. Results : The density of VSC by CBCT in TPS was $0.9g/cm^3$, and in the case of Spine Down Bar, it was $0.7g/cm^3$. The radiation was attenuated by 17.49%, 16.49%, 8.54%, and 7.59% at the Side Rail, Side Bar Upper, Side Bar Lower, and Spine Down Bar. For the accuracy of modeling, calculated dose and measured dose were compared. The average error was 1.13% and the maximum error was 1.98% at the $170^{\circ}beam$ crossing the Spine Down Bar. Conclusion : To evaluate the usability for the VSC modeled by TPS, the maximum error was 1.98% as a result of compassion between calculated dose and measured dose. We found out that VSC modeling helped expect the dose, so we think that it will be helpful for the more accurate treatment.

기업의 윤리정책이 윤리적 의사결정에 미치는 영향에 관한 연구 -개인특성의 조절효과를 중심으로-

양춘희 ( Chun Hee Yang ),권용만 ( Yong Man Kwon ) 한국인적자원관리학회 2009 인적자원관리연구 Vol.16 No.4

뇌동맥류 파열 위험성 예측을 위한 혈류 역학 기반 딥러닝 모델

양현동(Hyeondong Yang),조광천(Kwang-Chun Cho),김정재(Jung-Jae Kim),김재호(Jae Ho Kim),김용배(Yong Bae Kim),오제훈(Je Hoon Oh) 대한기계학회 2021 대한기계학회 춘추학술대회 Vol.2021 No.11

Cerebral aneurysms should be treated before rupture because ruptured cerebral aneurysms result in serious disability. Therefore, accurate rupture risk prediction is important and has been estimated using various hemodynamic factors. Our study aimed to suggest a new way to predict rupture risk in cerebral aneurysms using a deep learning model based on hemodynamic factors. A convolutional neural network (CNN) was utilized for rupture risk prediction for 123 aneurysm cases. To train the effect of hemodynamic parameters on the CNN, the hemodynamic parameters were first calculated using computational fluid dynamics and fluid-structure interaction. Then, they were converted into images for training the CNN using a novel approach. In addition, new data augmentation methods were devised to obtain sufficient training data. A deep learning algorithm based on hemodynamic factors, including WSS and strain, could be an effective tool for predicting rupture risk in cerebral aneurysms with good predictive accuracy.

전기동력 무인항공기의 추진시스템 효율 추정에 관한 연구

안일영,양용만,주영철,박상혁,배재성,Ahn, Il-Young,Yang, Yong-Man,Ju, Young-Chul,Park, SangHyuk,Bae, Jae-Sung 한국항공운항학회 2015 한국항공운항학회지 Vol.23 No.3

In the present study, we conducted the research on the high efficiency propulsion system for the development of long-endurance UAV with an electric propulsion system. For the long endurance UAV, fair aerodynamic characteristics with the high efficiency of the propulsion system is required because the flight power and the duration time of the long-endurance UAV vary greatly depending on the efficiency of the propulsion system. Therefore, in this study, the tracking program which records the performance of motor, propeller was developed because of their wide variation in the efficiency depending on the using condition, and records from the existing flight test program were utilized to check the accuracy of the program we had developed. For the development of future long-endurance solar UAV, we confirmed the applied voltage of motor, the optimal rotation of propeller and the gear ratio of reduction gear in order to get the highest efficiency on the propulsion system at the optimal flying condition.

21CM 우주전파 수신용 안테나의 제작

박종애,양종만,한석태,박용선,Park, Jong-Ae,Yang, Jong-Man,Han, Seok-Tae,Park, Yong-Seon 한국천문학회 1993 天文學論叢 Vol.8 No.1

We made a pyramidal horn antenna system for 21cm cosmic radio wave. The antenna system has a rectangular waveguide with $TE_{10}$ mode and a copper probe to detect the electromagnetic wave in waveguide. The parameters of the probe are obtained by experiments using two waveguides. Pyramidal horn antenna is designed to get a gain of 20dB. The size of the aperture of this horn is $94cm{\times}74cm$. The beam width of half power is about $14.7^{\circ}$ for the frequency of 1.4GHz. The horn is made of aluminum plate with a thickness of 2mm. The signal from horn and waveguide is amplified in a receiver system and is converted into DC in the detecter. The intensity of the signal is recorded on a chart recorder. We observed the sun using this simple radio telescope and obtained the brightness temperature of $2.2{\times}10^5K$, which indicates that the sun is quiet at 21cm.