유동해석 및 음향해석을 이용한 bleeding system 최적 설계

최재우(Jaewoo, Choi),김호진(Hojin, Kim),송재욱(Jaewook, Song) 한국유체기계학회 2016 유체기계 연구개발 발표회 논문집 Vol.2016 No.11

4년제 대학졸업 구직자의 구직선호 유형과 성별과 졸업대학 소재 지역에 따른 차이

최재우(Jaewoo Choi),강운선(Woonsun Kang) 동아인문학회 2015 동아인문학 Vol.33 No.-

본 연구는 한국교육고용패널조사(KEEP) 데이터를 활용하여 4년제 대학 졸업자들의 구직선호도의 잠재적 유형을 도출하고, 성별과 졸업대학 소재지에 따른 구직선호 유형의 차이를 밝히는데 목적을 두고 수행되었다. 잠재적 집단분석(Latent Class Analysis: LCA)을 활용하여 4년제 대학졸업자의 구직 선호도를 분석한 결과 4년제 대졸 구직자의 구직선호 유형은 ‘완생형(21%)’, ‘전통적 관념형(19%)’, ‘수도권일자리추구형(18%)’, ‘취업맹목형 구직자(16%)’, ‘칼퇴근 중시형(14%)’, ‘암니옴니형(7%)’, 그리고 ‘중소기업회피형(5%)’의 7개 집단으로 유형화되었다. 성별과 대학소재지가 구직선호 유형에 미치는 영향을 분석한 결과, 성별과 졸업대학 소재지역은 구직선호도 유형에 유의미한 영향을 미치는 것으로 밝혀졌다. This article examines whether there is latent class structure that adequately represents the heterogeneity in job preference of job seekers from university, and whether gender and location of university are predictive of membership in latent classes. For these, I address two researches problem: 1) Are there underlying types relate to job preferences of job seekers? If so, what are the types and their corresponding prevalence? 2) Are gender and location of university predictive of membership in job seekers classes? For these, data were used the Korea Education and Employment Panel(KEEP). Latent class analysis (LCA) and multinominal logistic regression carried out using PROC LCA for SAS. The results are following. Firstly, the respondents were grouped into seven latent classes: Secondly, gender and location of university were strong predictors of latent class membership of job seekers.

평가 기준의 조합에 따른 차원 축소 비교 연구

최재우(Jaewoo Choi),전용운(Yongun Jeon),박정선(Jungsun Park) 항공우주시스템공학회 2023 항공우주시스템공학회 학술대회 발표집 Vol.2023 No.05

복합화력발전소 경영진의 안전관심이 직원의 안전참여에 미치는 영향관계에서 조직요인의 매개효과 분석

최재우(JaeWoo Choi),엄성인(SungIn Um),홍인기(InGi Hong) 한국가스학회 2016 한국가스학회지 Vol.20 No.3

조직특성 및 안전문화는 매우 다양한 요인들을 포함하고 있으며, 그러한 안전문화의 향상을 위해서는 다양한 방법으로 접근되어야 한다. 구조방정식모형 분석을 통해 복합화력발전소의 안전문화 요인의 영향관계 검증결과 경영진의 관심도가 증가할수록 교육훈련정도의 향상과, 의사소통 및 안전참여의 향상에 긍정적인 역할을 함을 알 수 있었다. 그리고, 교육훈련 강도가 높을수록 근무향상에 도움이 될 것이 예측되었다. Organization characteristics and safety culture contains a wide variety of factors. It should be accessed in a variety of ways in order to improve such a safety culture. Thru by analyzing the safety culture factor of combined-cycle-power plants, it was found to be a positive role in the improvement and enhancement for the improving of safety training, communication and training participation level by structural equation modeling analysis as the management’s interest is increased. As the safety training is emphasized, it would be help to improve work participation.

환경공학과 대학생의 지속가능발전 태도에 대한 잠재적 집단 유형과 지속가능발전교육 경험과 학년에 따른 차이 분석

최재우(Jaewoo Choi),강운선(Woonsun Kang) 한국환경교육학회 2012 環境 敎育 Vol.25 No.4

The aim of research is to examine Environment Engineering Undergraduate Students Attitude towards Sustainable Development (SD). In this article the following two research questions were addressed: Firstly, Are there underlying types of environment engineering undergraduate students attitude about sustainable development? Secondly, are educational experience for sustainable development and year predictive of membership in types of environment engineering undergraduate students perception towards Sustainable Development (SD)? For this research, I carried out latent class analysis (LCA) and multinominal logistic regression. LCA is a statistical method used to identify a set of discrete, mutually exclusive latent classes of individuals based on their responses to a set of observed categorical variables. I used PROC LCA, SAS procedure for latent class analysis and multinominal logistic regression. The results are following. Firstly, 25.8% of respondents are expected to belong to the ecologism centered social welfare class. 6.0% of respondents are expected to belong to the techno-centrism centered social welfare class, 9.9% are expected to belong to the social welfare based economic growth class, 39.6% are expected to belong to the greenism class, 9.6% are expected to belong to the techno-centrism centered economic growth class, and 9.1% are expected to belong to the environment centered social and economic development class. Secondly, Both educational experience for sustainable development (p<.001) and year (p<.0001) were strong predictors of latent class membership.

유튜브 여행콘텐츠 특성이 몰입과 만족에 미치는 영향 연구

최재우 ( Jaewoo Choi ) 관광경영학회 2019 관광경영연구 Vol.88 No.-

This study has researched the effect of YouTube travel contents features on flow and satisfaction. First, this study has defined the relation of effect between YouTube travel contents and users' flow. Second, it has clarified the relation of effect between users' flow and satisfaction. Lastly, it has defined the relation of effect between YouTube travel contents features and satisfaction. With these research purposes, this study suggests practical implications for YouTube travel contents strategies of travel agency through the empirical research results. The survey was conducted from January 18th to January 28th in 2019. A total of 200 questionnaires were distributed and usable 195 questionnaires were analyzed after removing 5 irresponsible questionnaires. As a result of analysis, first, the only factor of amusement has a significant positive effect on pleasure with regard to the factor of YouTube travel contents features for users' flow. Also, with respect to time distortion, both variety and amusement have a statistically significant and positive influence on pleasure. Second, users' flow has a significant impact on satisfaction. Third, YouTube travel contents features have significant positive effect on satisfaction.

중장년층의 디지털 미디어 활용 기능 유형과 사회인구학적인 변인에 따른 차이

최재우(Jaewoo Choi),강운선(Woonsun Kang) 동아인문학회 2016 동아인문학 Vol.37 No.-

본 연구는 중장년층을 대상으로 디지털 미디어의 활용 기능을 유형화하고, 연령대, 성별, 소득, 학력과 같은 사회인구학적변인이 디지털미디어의 활용 기능 유형에 미치는 차별적 영향을 밝히는데 목적을 두고 수행하였다. 이를 위하여 정보통신정책연구원에서 제공하는 2015년 한국미디어패널 자료를 활용하였으며, 잠재적 집단분석(Latent Class Analysis: LCA)과 다중로지스틱 회귀분석을 실시하였다. 분석결과는 다음과 같다. 첫째, 디지털 미디어를 활용하기 위한 중장년층의 기능유형은 ‘디지털 문맹자(18%)’, ‘인터넷 입문자(12%)’, ‘인터넷 초보자(15%)’, ‘인터넷 중급자(18%)’, 그리고 ‘디지털 문식자(43%)’의 다섯 집단으로 유형화할 수 있다. 둘째, 연령대, 성별, 소득, 학력과 같은 사회인구학적 변인은 중장년층의 디지털 미디어의 활용 기능 유형에 유의미한 영향을 미친다. This article addressed two research questions were addressed: 1) Are there underlying types of digital skills among the middle-aged? In other words, is there a latent class structure that adequately represents the heterogeneity in underlying types of perception on digital skills? If so, what are the types? and how the middle-aged distributed types of the latent classes? 2) Are sociodemographic factors such as age, sex, grade, income predictive of membership in types of digital skills among the middle-aged? For the purpose of this study, we used the Korean Media Panel Data, and Latent class analysis (LCA) and multinominal logistic regression carried out using PROC LCA for SAS. The results are following. 1) the respondents were grouped into five latent classes: ‘digital illiterate (18%)’, ‘internet starter(18%)’, ‘internet beginner(12%)’ ‘internet middle level(5%)’, and “digital literate(43%). 2) Sociodemographic factors such as age, sex, grade, income were predictors of latent class membership.

스마트 관광 비즈니스 확장을 위한 여행플랫폼 모델의 탐색적 연구

최재우 ( Jaewoo Choi ) 관광경영학회 2019 관광경영연구 Vol.87 No.-

As an exploratory research on the travel platform model for the expansion of the smart tourism business, with the Team Heads and the Heads of the Business Departments in the travel business field as the subjects and as the interviewees of this research, by selecting the subjects who are scheduled to push ahead and plan regarding the travel platform as the interviewees, the expert interviews had been proceeded with the related items, including the following: Firstly, the direction of the travel platform: Secondly, the structure of the travel platform model; Thirdly, the constituent elements of the travel platform; Fourthly, the important matters when designing a travel platform; Etc. As a result of the research, in order to strengthen the competitiveness of a platform in the travel industry, the introduction, and the possibility of the utilization, of a cutting-edge technology regarding the travel information and the travel products and services are the very important elements. And, according to the expansions of the B2C, O2O, and OTA business models in the travel market, the preparation and the establishment of a customized-type, travel platform business model with the foreign tourists as the subjects are needed. And a standardization strategy regarding the process of the expansion of the travel platform business for drawing the agreement between the persons interested must be formulated. It is judged that, in the researches in the future, the specific, additional researches regarding the convenience of the travel platform users and regarding the commercialization of the platforms are needed.

복합발전 플랜트 안전문화 진단을 위한 시스템 다이내믹스 모델링 및 통합도구 개발 연구

최재우(Jaewoo Choi),엄성인(Sungin Um),홍인기(Inki Hong) 한국가스학회 2017 한국가스학회지 Vol.21 No.3

기업의 안전문화 측정에 있어 다양한 방법들이 시도되고 있으나, 평가방법에 따라 정형화되지 못한 주관적인 기준에 따른 정성적 분석결과를 도출하는 한계를 보인다. 이에, 복합발전 플랜트에 적용할 수 있는 설문지를 개발하고, 이 결과를 기반으로 시스템 다이내믹스 모델을 이용하여 평가결과의 정량화를 하였고, 다양한 시나리오를 통한 시뮬레이션을 실시하여 안전문화 측정과 함께 기업의 미래 안전문화 정책에 기준을 제시 하고자 하였다. Although various methods have been tried to measure the safety culture of firms, they are limited to derive the qualitative analysis results according to the subjective criteria that are not formalized according to the evaluation method. We developed a questionnaire that can be applied to a combined power plant, quantified the evaluation results using the system dynamics model based on the results, and conducted simulation through various scenarios. And to present the criteria for safety cultural policy.

시차변화(Disparity Change)와 장면의 부분 분할을 이용한 SLAM 방법

최재우(Jaewoo Choi),이철희(Chulhee Lee),임창경(Changkyoung Eem),홍현기(Hyunki Hong) 대한전자공학회 2015 전자공학회논문지 Vol.52 No.8

카메라를 이용하는 시각(visual) SLAM(Simultaneous Localization And Mapping)은 로봇의 위치 등을 파악하는데 널리 이용되고 있다. 일반적으로 시각 SLAM은 움직임이 없는 고정된 특징점을 대상으로 연속적인 시퀀스 상에서 카메라의 움직임을 추정한다. 따라서 이동하는 객체가 많이 존재하는 상황에서는 안정적인 결과를 기대하기 어렵다. 본 논문에서는 이동 객체가 많은 상황에서 스테레오 카메라를 이용한 SLAM을 안정화하는 방법을 제안한다. 먼저, 스테레오 카메라를 이용하여 깊이영상을 추출하고 옵티컬 플로우를 계산한다. 그리고 좌우 영상의 옵티컬 플로우를 이용하여 시차변화(disparity change)를 계산한다. 그리고 깊이 영상에서 사람과 같이 움직이는 객체에 대한 ROI(Region Of Interest)를 구한다. 실내 상황에서는 벽과 같은 정적인 평면들이 움직이는 영역으로 잘못 판단되는 경우가 자주 발생한다. 이런 문제점을 해결하기 위해 깊이 영상을 X-Z 평면으로 사영하고 허프(hough) 변환하여 장면을 구성하는 평면을 결정한다. 앞의 과정에서 판단된 이동 객체 중에서 벽과 같은 장면 요소를 제외한다. 제안된 방법을 통해 정적인 특징점이 요구되는 SLAM의 성능을 보다 안정화할 수 있음을 확인하였다. Visual SLAM(Simultaneous Localization And Mapping) has been used widely to estimate a mobile robot’s location. Visual SLAM estimates relative motions with static visual features over image sequence. Because visual SLAM methods assume generally static features in the environment, we cannot obtain precise results in dynamic situation including many moving objects: cars and human beings. This paper presents a stereo vision based SLAM method in dynamic environment. First, we extract disparity map with stereo vision and compute optical flow. We then compute disparity change that is the estimated flow field between stereo views. After examining the disparity change value, we detect ROIs(Region Of Interest) in disparity space to determine dynamic scene objects. In indoor environment, many structural planes like walls may be determined as false dynamic elements. To solve this problem, we segment the scene into planar structure. More specifically, disparity values by the stereo vision are projected to X-Z plane and we employ Hough transform to determine planes. In final step, we remove ROIs nearby the walls and discriminate static scene elements in indoor environment. The experimental results show that the proposed method can obtain stable performance in dynamic environment.