• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2010년 춘계학술대회논문집
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• pp.208-213
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• 2010

In this study CFD(Computational Fluid Dynamics) analysis of the steady fire-driven fuid flow for the performance test of ventilation at railway tunnel between Heuksok and Nodeul Station from Seoul Metro 9 is performed. There were fans with exhaust and intake modes and each was installed at the middle and both ends of the tunnel. For this test, the pool fire source of methyl alcohol with 1.5MW and smoke generators were installed between the middle of tunnel and Heuksok Station. In this test, the smoke behavior from natural convection was observed for 10 minutes from the ignition of pool fire and then fans with intake-modes at both sides of Heuksok effect of fan-on with intake mode located in the opposite side of the tunnel nearby Heuksok Station on fire-driven fluid flow is studied on when the boundary conditions of fan-on at the tunnel between Heuksok and Nodeul Station are the same as test. FLUENT, a commercial CFD code, is used for this analysis.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2010년도 춘계학술대회 논문집
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• pp.315-323
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• 2010

장대레일 교체주기는 자갈궤도 레일두부 표면요철과 레일 휨피로의 상관관계 분석을 통해 산정되었다. 본 연구에서는 국내 도시철도(서울메트로) 콘크리트궤도에서 레일두부 표면요철량에 따른 레일 휨응력을 측정하였다. 또한, 콘크리트궤도 레일두부 표면요철, 속도와 레일 휨응력의 상관관계를 분석하였다. 결론적으로, 중회귀분석을 통해 운행속도(U), 표면요철(v, w)에 따른 레일 휨응력(Y) 예측식을 도출하였다. 본 연구결과는 콘크리트궤도 장대레일 교체주기를 수립하기 위한 기초데이터로 활용이 가능할 것이다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 춘계학술대회 논문집
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• pp.1408-1415
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• 2007

To operate Platform Screen Door (PSD) automatically, the operational data of PSD and the train must be interfaced properly. PSD and train are operated together by the signaling system in Automatic Train Operation (ATO) signaling system zone where interfaces are provided between PSD and train. However, the additional PSD interface system with train is required in train operating zone without the interface between PSD and train. For the PSD interface, the wireless communication system or the train status (train correct stop status / train door status) detection system has been used. Seoul Metro line No.2. has the PSD wireless communication system using 447MHz band RF. For the safety of PSD operation, it is required to prevent RF interference in the subway environment where many frequencies exist. In this paper, the PSD wireless communication system is developed using 2.4GHz band RF to prevent the interference of the wireless communication and increase the traffic of the PSD interface. Furthermore, the improved system can store, manage and display the PSD and train operational data using Human Machine Interface (HMI) in the train's driver cab.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 추계학술대회 논문집
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• pp.1058-1070
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• 2007

Internal and external railway management corporations are using the periodic replacement criteria of rail by accumulated passing tonnage and wear to maintain rails for servicing. However, internal the periodic replacement criteria of continuous welded rail(CWR) by accumulated passing tonnage is the one(50kg/m-5 million gross tonnage, 60kg/m-6 million gross tonnage) presented in Japan before. It was estimated with the fatigue life about 50kg N rail joints applied diesel train load but it wasn't applied to current conditions of track; elimination of rail joint, using the concrete slab track and operation of light train load and effect of welding, manufacturing technique, grinding of rail. Therefore, in this study, it was investigated the types of damage and cause in welded rails and examined standards and information resources. Also, this study presents preliminary data to revise the periodic replacement criteria of CWR by current accumulated passing tonnage in bending test of laid welded rail and a survey of track maintenance history of Seoul metro.

• 전기학회논문지
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• 제64권7호
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• pp.1019-1025
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• 2015

The performance requirements on the safety-based functionality of railway signal systems have been reinforced and the effort for enhancement of the existing system or development of the new system is being accordingly made. In particular, various technical researches on replacement or improvement of the existing ATS(Automatic Train Stop) signaling system are now in progress for better operational efficiency. In this study, the complementary points for improvement or replacement of the currently used system(i.e., ATS) will be derived in terms of operating efficiency in an integrated operating environment with the newly introduced system(e.g., ATC: Automatic Train Control). This study can contribute to derive the need for improvement of the signaling system by checking the interface problems and comparing between different systems through the analysis of real operation cases in the field. Eventually, this analysis can be applied to prevent and estimate the collision accidents can be caused by the failure of the signaling system in advance. In addition, the results can be used to provide a future direction to secure the reliability in the parallel operation by integration based on different railway signaling systems.

• 노동경제논집
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• 제31권3호
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• pp.1-19
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• 2008

본 연구는 2007년부터 적용되기 시작한 감시단속적 근로자 그룹에 대한 최저임금의 효과를 실증적으로 분석하였다. 수도권 지역의 132개 단지 아파트 경비근로자들에 대한 2005~2007년의 임금 근로시간, 고용 등에 대한 자료를 분석한 결과 최저임금제 도입으로 표본 근로자들의 2007년도 임금은 약 10.9% 순상승하였고, 고용은 3.5~4.1% 감소하였으며, 월 근로시간은 약 13.5% 감소한 것으로 추정된다. 이는 고용의 단기 임금탄력성이 -0.312로, 근로시간의 단기 임금탄력성은 -1.68로 추정됨을 의미한다.

• 콘크리트학회논문집
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• 제21권5호
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• pp.649-660
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• 2009

내부 구속 중공 철근콘크리트(ICH RC, internally confined hollow reinforced concrete) 기둥의 비선형해석 모델을 제시하고 매개변수 연구를 수행하였다. 제안된 기둥 해석 모델은 콘크리트의 구속효과와 재료비선형을 고려하였으며, 해석 결과와 이 연구에서 수행된 ICH RC 기둥 실험 결과 및 선행 연구자들의 실험 결과를 비교하여, 해석 모델을 검증하였다. 검증 결과 제안된 기둥 해석 모델은 만족할 만한 결과를 보여주었으며, 매개변수 연구를 통하여 내부강관의 두께, 콘크리트의 강도와 중공비에 따른 ICH RC 기둥의 거동 특성을 나타내었다.

• 한국화재소방학회논문지
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• 제20권2호
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• pp.21-30
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• 2006

2003년 대구지하철 방화사고 이후 서울의 도시철도 7호선 방화를 비롯해 해외에서도 이와 유사한 모방 범죄가 발생하고 있다. 지하철의 방화사고는 대부분 유류나 가스 등을 이용한 방화유형이 대표적으로 발화 후 수분 내에 차량 내부가 전소될 수 있어 궁극적으로 지하철 전노선을 마비시키는 결과를 초래할 수 있다. 따라서 화재발생과 확산을 단계적으로 차단하거나 화재로부터 신속히 격리할 수 있는 효과적 초기 대응의 대안을 제시함으로서 대형 재난을 피할 수 있다. 본 연구에서는 국내외 지하철 방화 사고의 진행과정을 분석하여 대응 단계별로 방화 상태의 피해확인 및 인지 여부, 초기진화 여건 판단, 대응 조직의 상황전파 및 피난유도과정을 비상상황 등급별로 시나리오상에 전개했다.

• 대한가정학회지
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• 제30권2호
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• pp.113-137
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• 1992

The purpose of this study was to figure out the urban establishing families' economic structures(income, expenditure, assets, first-present-future housing cost etc.), the states of first-present housing, the future housing plans, and the housing preferences. For this purpose 274 establishing families in Seoul and its metro-politan area were interviewed through the standardized questionnares. Finally 264 questionnares were analyzed. The major findings were as follows; 1. The important source of their monthly incomes was the labor income. But there was often the transfer income from their parents. And the important items of monthly expenditures were savings and foods. In higher income classes, the traffic cost was important relatively. 2. It was found that the urban establishing families were very dependent on their parents for their first-present housing costs. The dependency was stronger in high education classes compared to the low. This was the case in future housing costs. 3. The states and changes of first-present housing showed the demands for an apartment, homeowership, and privacy. These tendencies were higher in high education classes compared to low education classes, but the demands for future housing were according to the monthly income. The present locations were determined majorly by the distance from office and parents. 4. Their housing preferences were different from the present housing states. Furnished rental housing, open living space, large common spaces, and common using of unusual appliances etc. were more preferred by high education classes compared to low education classes.

• 한국철도학회논문집
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• 제17권2호
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• pp.148-155
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• 2014

본 연구는 수도권 도시철도 운영기관에 종사하는 철도교통관제사를 대상으로 이들의 스트레스 요인을 파악하고 스트레스가 직무만족에 미치는 영향을 실증적으로 검증하였다. 분석결과, 조직차원 스트레스 7개 요인 중 조직체계, 보상부적절, 직장문화, 직무요구 4개 요인, 그리고 관제업무수행 스트레스 3개 요인 중 커뮤니케이션 요인이 직무만족에 영향을 미치는 것으로 확인되었다. 뿐만 아니라, 설문대상자의 서술형 설문내용을 분석한 결과 현장부서와의 소통 및 각종 민원처리 등이 가장 큰 스트레스 요인으로 이에 대한 스트레스 완화방안을 제언하고자 한다.