디젤기관의 신기술 개발동향

최재성,Choi Jae-Sung 한국마린엔지니어링학회 2004 한국마린엔지니어링학회지 Vol.28 No.7

구간분할에 따른 고속도로 사고 빈도 모형에 관한 연구

최재성,김상엽(Kim, Sang-Yeop),황경성(Hwang, Gyeong-Seong),허태영(Heo, Tae-Yeong),조원범(Jo, Won-Beom),김용석 대한교통학회 2009 대한교통학회 학술대회지 Vol.61 No.-

고속주행상황의 운전자 인지·반응시간에 관한 연구

최재성,정승원,김정민,김태호,신준수 한국도로학회 2017 한국도로학회논문집 Vol.19 No.1

PURPOSES : The desire of drivers to increase their driving speeds is increasing in response to the technological advancements in vehicles and roads. Therefore, studies are being conducted to increase the maximum design speed in Korea to 140 km/h. The stopping sight distance (SSD) is an important criterion for acquiring sustained road safety in road design. Moreover, although the perception-reaction time (PRT) is a critical variable in the calculation of the SSD, there are not many current studies on PRT. Prior to increasing the design speed, it is necessary to confirm whether the domestic PRT standard (2.5 s) is applicable to high-speed driving. Thus, in this study, we have investigated the influence of high-speed driving on PRT. METHODS : A driving simulator was used to record the PRT of drivers. A virtual driving map was composed using UC-Win/Road software. Experiments were carried out at speeds of 100, 120, and 140 km/h while assuming the following three driving scenarios according to driver expectation: Expected, Unexpected, and Surprised. Lastly, we analyzed the gaze position of the driver as they drove in the simulated environment using Smarteye. RESULTS: Driving simulator experimental results showed that the PRT of drivers decreased as driving speed increased from 100 km/h to 140 km/h. Furthermore, the gaze position analysis results demonstrated that the decrease in PRT of drivers as the driving speed increased was directly related to their level of concentration. CONCLUSIONS : In the experimental results, 85% of drivers responded within 2.0 s at a driving speed of 140 km/h. Thus, the results obtained here verify that the current domestic standard of 2.5 s can be applied in the highways designated to have 140 km/h maximum speed

택지개발지구에서 보행자도로 공급수준 평가지표 개발

최재성,황경성,김상엽,장영수,박신원 대한교통학회 2009 대한교통학회지 Vol.27 No.2

This paper presents an evaluation index for the supply levels of pedestrian facilities in residential area planning. The pedestrian facility supply levels reveal the quality of a residential area, and can be associated with the resident living standards and satisfaction, pedestrian safety levels, and the effectiveness of the construction cost. This research conducted multifaceted procedures for the index development, and these procedures start first by identifying dominant influencing factors on pedestrian travel demand by reviewing the final reports of site planning in more than eight already-completed residential development sites. Second, based on the Space Syntax model, which was initially developed in the UK by establishing statistical relationships among an integration index, population size (persons/day), and the total development area, this research formulated a set of pedestrian demand estimation models. Then these models were utilized in forming a pedestrian facility supply index by integrating the new models and their results with the available accepted practice in the residential planning sector. This was necessary because planners want to understand the total supply level of pedestrian facilities in a residential area during the initial design stage. Finally, to test the model validity in satisfying pedestrian satisfaction, the research included a resident satisfaction interview, and it was revealed that the evaluation index developed in this research could provide planners and engineers with more promising results. It is therefore anticipated that this research can be of service when designing pedestrian facilities in future residential area planning and design activities. 본 논문에서는 주민 쾌적성, 보행자 안전성, 그리고 택지개발의 효율성을 제고시킬 수 있는 보행자 도로 공급 수준 평가지표를 제시한다. 이를 위한 연구에서 다각적인 분석이 시행되었는데, 첫째, 이미 입주가 끝난 8개 택지개발 사업지에서 보행수요에 미치는 영향요소를 찾았고, 영향 요소 간 관계를 정립하기 위해 Space Syntax 분석을 통한 국부통합도, 활동인구(인/일), 택지개발지구 면적 등을 선택하여 보행수요 예측모형을 정립하였다. 그 후 기존 연구에서 제시한 보행점유공간과 본 연구에서 개발한 보행수요 예측모형을 상호 비교하여 최초 계획단계에서 보행자 도로 공급수준을 산정할 수 있도록 했다. 끝으로, 본 연구에서 정립한 평가지표가 합리적인 공급수준을 평가하는 지표인지 확인하기 위해 주민 만족도 설문조사를 실시했는데, 그 결과 본 연구에서 정립한 평가지표는 기존 지표보다 우수한 것으로 나타났다. 앞으로 본 연구 결과는 택지개발 사업지에서 보행공간을 계획할 때 많은 도움을 제공할 것이다.

[해외리포트] 파리의 친환경 교통수단 보급 동향

최재성,김광호 국토연구원 2019 국토 : planning and policy Vol.453 No.-

조선·해양플랜트 엔지니어링 글로벌 시장 진출을 위한 전략

최재성,김정돈 해양환경안전학회 2019 해양환경안전학회 학술발표대회 논문집 Vol.2019 No.11

저탄소형 국토와 도시구조를 만들어나가야 합니다

최재성 국토연구원 2019 국토 : planning and policy Vol.450 No.-

TP-13 : 노인 만성폐쇄성폐질환(COPD) 환자에서 증세와 우울증과의 관계

최재성,김영일,이호성,나주옥,김용훈,이화영 대한결핵 및 호흡기학회 2013 대한결핵 및 호흡기학회 추계학술대회 초록집 Vol.116 No.-

목적: 우울증이 있는 COPD 환자에서 폐기능과 임상 양상의 변화를 알아보고자 하였다. 방법: 2012년 9월부터 2012년 11월까지 순천향대학교 천안병원 호흡기내과에 COPD로 외래를 방문한 65세 이상의 환자를 대상으로 무작위로 표본 추출하였다. 성적: 남성 57명, 여성 30명이었고, 평균 연령은 74.00±6.41세(남성 73.63±6.46세 여성 74.70±6.36세)였다. 우울증 유병률은 Hamilton Rating Scale for Depression (HDRS)은 21명(24.7%), Patient Health Questionnaire-9 (PHQ-9)은 27명(31.0%), Patient Health Questionnaire-2 (PHQ-2)는 7명(8.0%), Geriatric Depression Scale-Short Form-Korea (GDS-SF-K)는 20명(23.0%)이었다. 추적관 찰된 COPD 환자에서 GOLD criteria에 따른 분류는 mild, moderate, severe, very severe가 각각 28,33,17,4명이었고 HDRS는 4.92±3.80, 3.70±3.00, 5.94±4.22, 10.00±10.92로 폐기능의 감소가 심할수록 우울증 척도 점수가 증가하였다(p=0.027). HDRS-우울증 군(mild 7, moderate 4, severe 7, very severe 2명)은 정상군(62명)에 비해 FEV1(L)의 의미있는 차이(1.53±0.32 vs 1.62±0.29, p> 0.05)는 없었으나 CAT score (22.4±10.2vs16±5.3, p=0.045)는 의미있게 높았다. 1년간의 추적관찰에서 FEV1 (mL)의 감소 폭은 두 군간에 의미있는 차이가 없었으나(8.4±8.2 vs 7.7±7.4, p>0.05), CAT 점수(23.6±11.4vs15.4±6.7, p=0.014)는 우울증 군에서 더 높았다. 급성악화 빈도는 우울증군이 정상군에 비해 증가하는 경향만 보였다(1.8±1.1vs1.6±0.5, p=0.054). 결론: 우울증이 있는 COPD 환자는 증세 변화가 심하여 우울증에 대한 적절한 평가와 치료가 필요하다.

PTEN and p53 Mutations in Endometrial Carcinomas

최재성,서광선,노흥태,이윤이,나선영,이혜경 대한병리학회 2005 Journal of Pathology and Translational Medicine Vol.39 No.1

Background : Endometrial carcinomas are pathogenetically classified into two major types; endometrioid carcinoma (EC) and serous carcinoma (SC). The most frequently altered gene in EC is the PTEN tumor suppressor gene (TSG). SC is usually associated with mutations in the p53 TSG. Methods : To further determine the role of PTEN and p53 mutation in endometrial carcinogenesis, the analysis of 33 endometrial carcinomas, including 28 ECs and 5 SCs, for loss of heterozygosity (LOH) on 10q23 and for mutation in all 9 coding exons of PTEN and the 5-8 exons of p53, using SSCP-PCR methods was carried out. Results : LOH was detected in at least one marker in 12 (54.5%) of 22 ECs, but in only one (20.0%) of 5 SCs. Somatic PTEN mutations were detected in 10 (35.7%) of 28 ECs. PTEN was altered in 67.9% of ECs and in 20.0% of SCs, including those with 10q23 LOH. No PTEN mutations were found among the SCs. Somatic p53 mutations were detected in 2 (7.1%) of 28 ECs and 3 (60.0%) of 5 SCs. Conclusions : PTEN gene alterations contribute to the pathogenesis of an endometrioid subtype of endometrial carcinoma, but not to the serous type. In contrast, p53 plays an important role in the pathogenesis of SCs.

미국 노인요양원 산업으 효율성 분석 ; 확률전선(前線) 비용모델을 적용한 사례

최재성 연세대학교 사회복지연구소 1995 연세사회복지연구 Vol.2 No.-

Measuring organizational performance using the concept of efficiency has not been easy because of technical and logical difficulties. Stochastic frontier cost model allows to measure organizational performance under the concept of efficiency. Further, the model makes it possible to estimate the efficiency of the industry itself which the organization belongs to. This study, using stochastic frontier cost model, analyzed 540 U.S. nursing homes (N=19,100) to estimate an individual efficiency and to find affecting factors. Especially, the study analyzed whether or not differences in ownership type and management styles affect efficiency. Operating costs per patient day was the dependent variable for the cost model. Independent variables were service mix, case mix, service quality, location factors, etc. Findings indicated that profit-making incentive in ownership did not turn out significantly affecting efficiency. However, chain-affiliation appeared to improve efficiency. This study also presented that the nursing home care industry used 28 percent of operating costs per patient day, inefficiently. Measuring efficiency using stochastic frontier cost model can be applied to evaluate the performance of diverse social welfare service providers in Korea. Approaching by provider types such as Social Welfare Service Center (N=250), Employees Medical Insurance Associations (N=150), Community Medical Insurance Associations (N=140), and child care centers, one can estimate efficiency of service delivery system and find out affecting factors.