• Proceedings of the KSR Conference
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• 2011.10a
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• pp.2135-2146
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• 2011

The rail surface irregularity is generated severely by train braking effect in the section of station. The braking force increases slip rate and friction factors caused by wheel-rail contact points. It brings rail surface irregularity as well. In this study, interactions between wheel and rail were investigated using rolling contact fatigue theory and mechanism of rail degradation through fracture mechanics. For the more, the Von-Mises stress occurred on the rail due to the interaction between wheel and rail was analyzed using 3-D finite element method. The amounts of surface irregularity of rail were measured according to accumulated passing tonnage in urban railway in fields. Therefore, the maintenance of rail should be separated by running and braking sections to prevent RCF defects.

• Korean Management Science Review
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• v.31 no.2
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• pp.49-63
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• 2014

With the huge concerns on the inefficiency of public enterprises, particularly a significant amount of debt, an increasing number of studies have been carried out to analyze the levels of inefficiency and investigate the causes of that inefficiency. However, very limited range of analytical methodologies have been used in the efficiency analysis and moreover, the effects of external factors have been little addressed. This study explores the efficiency of urban railway corporations in Korea by utilizing a method of stochastic frontier analysis (SFA). In particular, the potential effects of external factors including residential and floating populations of a station were statistically analyzed. A total of seven Korean urban railway corporations were selected to compare each other in terms of operational efficiency. The results present three important findings. First, the Cobb-Douglas model was found to be more valid for SFA compared to the Translog model. Second, the efficiencies of urban railway corporations in Seoul and Busan are relatively high whereas those of Daejeon and Gwangju are very low in efficiency in the area of sales revenue. In an aspect of number of transport of passengers, Gwangju Metro also showed the lowest efficiency. Third, the external factors are significantly associated with the efficiency, indicating that the efficiencies of Daejeon Metro and Gwangju Metro would increase while the efficiency of Seoul Metro would decreases when the external variables are excluded in the efficiency analysis. The results provide several meaningful implications for managers of the urban railway corporations as well as policy makers who are attempting to resolve the inefficiency problems of public enterprises.

• Journal of architectural history
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• v.28 no.6
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• pp.55-65
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• 2019

Ganggyeong, a city which is located at riverside of Geum River, played a role to connect the inland cities and the coastal cities through the Geum river waterway. In Chosun dynasty, Ganggyeong was one of the three major markets in Korea, and at the same time, it was one of the two river docks in Korea. However, after the railway was installed in Korea, railroad was more important than waterway in transporting logistics and in 1911 Honam railroad and Ganggyeong railway station was installed. Thus it was necessary to reorganize urban structure of Ganggyeong city from the traditional river-dock city to modern railroad city. In addition, urban infrastructure to prevent flood damage was needed because Ganggyeong suffered from floods and water shortages every year. Therefore, between 1910s and 1930s large-scale social infrastructures including road, water and sewage system, river bank, floodgate was constructed not only to revitalize the declining city but also to prevent flood damage and water shortages that hinder urban development. The installation of urban infrastructure has enabled the urban expansion and development of Ganggyeong city, and it is still served as a basic urban structure.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.98-103
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• 2010

There should be a need for measures to build up environmentally friendly transport system with new town for residence being built near metropolitan area. In order to promote the development of station influence area, convenience for public transport users and LRT(Light Rail Transit) construction, request for the speed improvement of urban transit is on the rise for easy access to the metropolitan area. This paper delves into the efficient operation of high speed train suitable for passenger demand estimates, and seeks to ensure integrated transportation system with subway Line 9 following the construction of Gimpo urban railway.

• Proceedings of the KSR Conference
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• 2011.05a
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• pp.181-199
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• 2011

Concentration of people in urban areas and development around Metro make exceed the passenger number which was calculated when the Metro station was built, in the result the Metro stations are crowed this is the study on the improvement of Metro station's congestion in urban areas for ensuring the passenger safety, the space of evacuation path and promoting the more pleasant riding environment with an environmental- friendly approach.

• Journal of computational fluids engineering
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• v.21 no.4
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• pp.61-70
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• 2016

Dong-tan Station, shared by high-speed railway and urban express railway, is a very complicated underground station having 6 tracks together with barrier and shafts between them, therefore it seems very hard to investigate the aerodynamic effects including the pressure variation and train gust in the station when a high-speed train runs through it. In this study, the aerodynamic effects on the structures and platform passengers when a high-speed train runs through an underground station have been studied using Computational Fluid Dynamics. STAR-CCM+ has been employed for numerical simulation based on Navier-Stokes equation and 2-equation turbulence model and moving mesh scheme supported by STAR-CCM+ has also been used to represent the relative motion between a train and station. Based on the simulation results, the unsteady flow fields in the underground station induced by the high-speed train have been analyzed and the pressures on the PSDs and pressure variation at the platform have quantitatively assessed.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.630-635
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• 2008

An urban transit is representative public transportation which lots of people take everyday. Especially, the station of urban transit is one of the very important public civil infrastructures. From the teachings of subway fire disaster occurred at Daegu on 2003, a certain incident might create large numbers of deaths or injuries and a lot of damages to the subway station without having an accurate grasp of emergency situation and doing proper action on the situation. Therefore, the passive surveillance system, which means the present CCTV based system, needs to be changed into the active one. The active surveillance system is the CCTV based system with intelligent softwares which affords to prevent a certain incident or trouble and its aggravation. In this paper, the state of the art of the representative companies developing intelligent softwares and its application sites of Australia and Hong Kong are briefly introduced. Finally, with the consideration of its recent trends, some technical contents for the intelligent surveillance system of domestic urban transit are briefly described.

• Proceedings of the KSR Conference
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• 2005.11a
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• pp.699-704
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• 2005

In the station of the railway and the subway various illumination equipment and a general power equipment for a passenger convenience, the signal equipment and the communication equipment which is necessary to the train operation provided. At the all of like this equipment from the electric room which is established in each station by changing from high voltage to low voltage and it supplies from the illumination transformer, the power transformer and the signal transformer. If it supplies to the equipment from the high voltage to the low voltage, it must be established to contact protection device in between the high voltage coil and the low voltage coil. Also it must do the grounding faulting device at the low voltage lines, the earthing devices at apparatus for the protection of an electric shock and an electric fire by the electric relation law. Compared the related regulations between the facilities which require protective functions such as grounding fault or earthing in public utilities like subway stations, and the facilities which do not require line earthing or protective functions such as electricity supplied for signalling the train. Also, will describe a countermeasure for the accident from a grounding fault.

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.93-99
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• 2008

The SeoulMerto, operating subway line No.$1{\sim}4$, was constructed in the metropolitan Seoul with the highest population. When it was built, the design was challenged to sharp curved tracks considering the protection of buildings, cultural assets, the connection to ground roads and rivers as well as to elevated railway in some parts. Lots of residential apartments and business complex have gradually increased in the area around subway stations and railway lines according to the urban development. Consequently, Requirements of better quality of life and comfortable environment caused the citizen complain for the noise. It has become one of serious social issues. In this paper, Noise level was analyzed using noise map measured in the running train of all routes. The analysis on the noise level was conducted according to railway type, track components type, seasonal type, retirement degree of the vehicle and subway station. Especially, Noise characteristics were analyzed by noise level data measured in the inside and outside of the train with geometry types of the concrete track. This study will contribute fundamental data for the "The Development of Sound-Absorbing Block on Concrete Track" promoted on The National R&D Project.

• Journal of the Korean Society for Railway
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• v.15 no.3
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• pp.300-305
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• 2012

The saving of time, which is defined as the demand from passengers and the supply from the urban railway, must be balanced. The selected factors influencing on the balance are the traffic, customer contact facilities, the number of failures, customer complaints(VOC), passenger moving time and transfer stations. Also, the overall ratio of SMRT's 4 lines is generated by differentiating the rate of each attribute in each factor. This is not only to differentiate the stations with peculiar factors but also to standardize criteria of the personalized services. Furthermore, as part of standardization, standard drawings of facility management are prepared for the improvement on the management of human resource and material. The drawings include passenger moving lines, location of safety incidents and also indicate the rating of the factors in each station and overall evaluation rating. In conclusion, this thesis aims to improve customer satisfaction constantly by reducing passenger moving time, through the differentiated management of each station.