액체금속로 Y-구조물의 비탄성 열응력 해석 및 손상평가에 관한 유한요소해석

곽대영,임용택,김종범,이형연,유봉,Kwak, D.Y.,Im, Y.T.,Kim, J.B.,Lee, H.Y.,Yoo, B. 대한기계학회 1997 大韓機械學會論文集A Vol.21 No.7

LMFBR(Liquid Metal Fast Breeder Reactor) vessel is operated under the high temperatures of 500-550.deg. C. Thus, transient thermal loads were severe enough to cause inelastic deformation due to creep-fatigue and plasticity. For reduction of such inelastic deformations, Y-piece structure in the form of a thermal sleeve is used in LMFBR vessel under repeated start-up, service and shut-down conditions. Therefore, a systematic method for inelastic analysis is needed for design of the Y-piece structure subjected to such loading conditions. In the present investigation, finite element analysis of heat transfer and inelastic thermal stress were carried out for the Y-piece structure in LMFBR vessel under service conditions. For such analysis, ABAQUS program was employed based on the elasto-plastic and Chaboche viscoplastic constitutive equations. Based on numerical data obtained from the analysis, creep-fatigue damage estimation according to ASME Code Case N-47 was made and compared to each other. Finally, it was found out that the numerical predictio of damage level due to creep based on Chaboche unified viscoplastic constitutive equation was relatively better compared to elasto-plastic constitutive formulation.

CHABOCHE 통합 점소성 구성방정식을 이용한 재료거동해석

곽대영,임용택,김종범,이형연,유봉,Kwak, D.Y.,Im, Y.T.,Kim, J.B.,Lee, H.Y.,Yu, B. 대한기계학회 1996 大韓機械學會論文集A Vol.20 No.11

Service conditions for structures at elevated temperatures in nuclear power plant involve transient thermal and mechanical load levels that are severe enough to caeuse inelastic deformations due to creep and plasticity. Therefore, a systematic mehtod of inelastic analysis is needed for the design of structural components in nuclear poser plants subjected to such loading conditions. In the present investigation, the Chabodhe model, one of the unified viscoplastic constitutive equations, was selected for systematic inelastic analysis. The material response was integrated based on GMR ( generallized mid-point rule) time integral scheme and provided to ABAQUS as a material subroutine, UMAT program. By comparing results obtaned from uniaxial analysis using the developed UMAT program with those from Runge-Kutta solutions and experimentaiton, the validity of the adopted Chaboche model and the numerical stability and accuracy of the developed UMAT program were verified. In addition, the developed material subroutine was applied for uniaxial creep and tension analyses for the plate with a hole in the center. The application further demonstrates usefulness of the developed program.

Lactobacillus crispatus KLB46의 스트레스 전처리시 열 내성 증진효과

곽대영(Dae-Yung Kwak),강창호(Chang-Ho Kang),전한을(HanEul Jeon),소재성(Jae-Seong So) 한국생물공학회 2014 KSBB Journal Vol.29 No.2

Lactobacilli, the dominant species of microorganisms in the vaginal flora of healthy women, play important roles to prevent bacterial vaginosis and other sexually transmitted diseases. In this study, we carried out studies on stress adaptation prior to various stress treatment. We found that heat or salt adapted KLB46 showed higher cell viability than non adapted upon heat stress at 60℃ for 20 min. When chloramphenicol was added during the adaptation process, heat tolerance was abolished. This result suggested that de novo protein synthesis was essential during adaptation.

SNS 관광정보의 신뢰 및 만족수준에 따른 정보공유 및 사용의도 차이

곽대영(Dae Young Kwak) 한국전자통신학회 2017 한국전자통신학회 논문지 Vol.12 No.1

본 연구는 SNS 관광정보의 신뢰와 만족수준에 따른 사용자의 정보공유 및 이용의도의 차이를 조사, 분석함으로써 SNS를 통해 관광정보를 제공하는 회사들과 관련 서비스 운영자들에게 시사점을 제공하고자 하였다. 이를 위해, 문헌연구를 통해 SNS 관광정보에 대한 사용자의 신뢰와 만족, 관광정보의 공유의도 및 사용의도에 대한 선행연구들을 조사하고, 표본조사법을 통해 SNS 관광정보 이용경험자들의 의견을 수집, 통계적 분석을 실시하였다. 분석결과, SNS 관광정보의 신뢰와 만족수준에 따라 사용자의 정보공유 및 사용의도에 모두 차이가 있는 것으로 나타나, SNS를 통해 관광정보를 제공하는 기업들 및 서비스 제공자들에게 이와 관련한 시사점을 제시하였다. The objective of this study is to suggest useful directions to the companies providing tourism information through SNS and the related service providers through investigating differences of sharing and use intention of SNS tourism information according to the level of trust and satisfaction. To achieve the objective, as a conceptual framework of the study, the literature on trust and satisfaction about SNS tourism information and information sharing and use intention were reviewed, and the empirical studies on the perception of the people who experienced the service was conducted. The findings showed that there were differences of sharing and use intention of SNS tourism information according to the level of trust and satisfaction

외국인 환자의 국내 의료관광 상품만족도에 관한 연구 -의료서비스 분야별 차이검증을 중심으로-

곽대영 ( Dae Young Kwak ) (사)한국마이스관광학회(구 한국컨벤션학회) 2013 MICE관광연구 Vol.13 No.1

The objectives of this study are to investigate foreign patients` satisfaction levels with domestic medical tourism products. To achieve these objectives, as a conceptual framework of the study, the concept and definition of medical service, and medical service quality and satisfaction were reviewed, and the empirical studies on the satisfaction levels of foreign patients who have received domestic medical or health care services were conducted. According to the findings of this study, the following suggestions were presented to the domestic healthcare and medical institutions. First, domestic healthcare and medical institutions, especially small private hospitals and clinics are required to improve and equalize their overall service qualities including service mind and communication skill of medical team and other employees, medical and other facilities, service procedures and costs through comparing with domestic and overseas advanced healthcare and medical institutions` those. Second, dermatology clinics which were low estimated comparatively in satisfaction level should try to enhance their overall service qualities continually by comparing with other departments`, and health spa need to improve employees` communication skills.

전시업체의 전시회 참여성과에 영향을 미치는 요인에 관한 연구 -국제관광전시회 및 나노융합대전을 중심으로-

곽대영 ( Dae Young Kwak ),임형택 ( Hyung Taek Lim ) (사)한국마이스관광학회(구 한국컨벤션학회) 2013 MICE관광연구 Vol.13 No.3

The objectives of the this study are to suggest useful directions for the development of domestic exhibition industry through investigating and analyzing exhibitors` comprehensive perceptions regarding participation of exhibition. To achieve these objectives, as a conceptual framework of the study, participation performance of exhibition, exhibition choice attributes and exhibition quality were reviewed, and the empirical studies on the opinions of exhibitors who participated in the 26th Korea World Travel Fair and Nano Korea 2013 were conducted. According to the findings of this study, the factor affecting ``sales performance`` of exhibition participation performance was ``internal factor`` of exhibition choice attribute, and the factors affecting ``performance except sale`` of exhibition participation performance were ``internal factor`` and ``external factor`` of exhibition choice attribute. And no differences exist in participation performance of exhibition in accordance with exhibitors` characteristics.

PC기반 소성가공공정 성형해석 시스템 개발

곽대영(D. Y. Kwak),천재승(J. S. Cheon),김수영(S. Y. Kim),이근안(G. A. Lee),임용택(Y. T. Im) 한국소성·가공학회 2000 소성가공 : 한국소성가공학회지 Vol.9 No.3

전시업체 유형별 전시회 선택속성에 관한 연구

곽대영 ( Dae Young Kwak ) (사)한국마이스관광학회(구 한국컨벤션학회) 2014 MICE관광연구 Vol.14 No.3

The objective of this study is to suggest useful directions for exhibitor attracting strategy of exhibition organizers through dividing the exhibitors who participated in the exhibitions, ``Electronics Manufacturing Korea 2014`` and ``The 29th Korea World Travel Fair``, into several groups by exhibition choice attribute, and comparing and analyzing the differences among the groups. To achieve the objective, as conceptual framework of the study, the literature on concept and effect of exhibition, and exhibitor``s exhibition choice attribute were reviewed, and the empirical study on exhibitors`` perception about exhibition choice attribute was conducted. According to the findings of this study, the following suggestions were presented to exhibition organizers. First, for the exhibitors belonging to the group1 named passive ``external factor`` pursuit type, exhibition organizers are needed to try to choice well known exhibition center and to promote exhibition actively through various mass media and to enhance their operation ability continuously. Second, for the exhibitors belonging to the group2 named ``sale activity factor`` pursuit type, exhibition organizers will have to set conditions in order to take place a lot of sales via exhibition. Third, for the exhibitors belonging to the group3 named active ‘choice attribute factor’ pursuit type, exhibition organizers will have to make preparations not just only for the conditions for the above 2 types but also for the conditions for remaining 2 choice attribute factors, which are ``internal factor`` related to marketing strategy and ``non sales activity factor`` relevant to various information gathering and distribution channel investigation.

국제관광전시회 참여업체의 재 참여의사에 영향을 미치는 요인

곽대영 ( Dae Young Kwak ) (사)한국마이스관광학회(구 한국컨벤션학회) 2014 MICE관광연구 Vol.14 No.1

The objective of this study is to suggest useful directions for domestic exhibition organizers through investigating and analyzing the factors affecting reparticipation intention of international tourism show``s exhibitor. To achieve the objective, as conceptual framework of the study, the literature on tourism exhibition and the factors affecting reparticipation intention of exhibition were reviewed, and the empirical study on exhibitors`` perception of international tourism exhibitions about reparticipation intention of exhibition was conducted. According to the findings of this study, the following suggestions were presented to domestic exhibition organizers. First, exhibition organizers are needed to try to induce noted institutions and companies in tourism field to participate their exhibitions, and to promote them through various media in order for the exhibitors to achieve participation results. Second, it is necessary for exhibition organizers to benchmark foreign renowned exhibitions to enhance operation and facility quality of their exhibitions. Third, exhibition organizers are needed to try to host noted exhibitions, and to increase their reputation as exhibition organizer and maintain it.

소성가공공정 해석을 위한 3차원 해석 시스템 개발

곽대영(D. Y. Kwak),김수영(S. Y. Kim),임용택(Y. T. Im),채수원(S. Y. Chae) 한국소성·가공학회 2000 소성가공 : 한국소성가공학회지 Vol.9 No.7