• Journal of the Korean Society for Railway
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• v.19 no.5
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• pp.609-616
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• 2016

The Passenger Service Equipment(PSE) provide various train operation data such as flag station data. When PSE incur service failures or errors, passengers who use the train feel great inconvenience. In this paper, I have chosen PSE that were important to passengers and have applied Reliability Centered Maintenance(RCM), deviating from the existing perspective that operators have taken to perform RCM. FMEA/FMECA was performed for reliability analysis of the PSE. The highly critical device among the PSE is defined as the Passenger Information Control System(PICS), which is used to control the automatic announcement and signaling board. Through Weibull distribution of the PICS, failure analysis was performed. Based on the analyzed results, I have proposed a solution that will minimize service failure of PICS.

• Journal of the Korean Society for Railway
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• v.19 no.4
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• pp.468-479
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• 2016

In order to supply power to online monitoring systems that are attached to high voltage catenary or overhead wires, a wireless power transfer system is required that is able to transmit power over the insulation gap. Such wireless power transfer systems have transmitter and receiver coils that have diameters of over 10cm. This paper focused on an investigation of the sources of loss in the coils when the coils are fabricated using printed circuit board technology. Using finite element simulation results, it has been shown that the dielectric loss in the substrate was the dominant source of the total loss. It has been demonstrated that the selection of a proper dielectric material was the most critical factor in reducing the loss. For further reduction of the loss, the distributed tuning capacitor method and the slotting of the inter-turn spaces have been proposed. For the evaluation of the proposed methods, four coils have been fabricated and their equivalent series resistances and quality factors were measured. Measured quality factors were greater than 300, which means that these devices will be helpful in achieving high coil-to-coil efficiency.

• Proceedings of the KSR Conference
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• 2011.05a
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• pp.613-618
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• 2011

More than 7 million persons use Seoul Metropolitan Subways (SMS) everyday and the number has been in increasing trend. With the increasing trend of concerns on indoor air quality(IAQ), the management of IAQ has become an important issue, especially in case of subway operators, because most of subway lines are placed underground with poor ventilation condition. The ultimate object of study develop independent cleaning device that reduce efficient fine particle and $CO_2$. Urban subway has characteristics about proper clean air flow, must be installed in narrow space and maintenance cycle has enough time. Two layered electrically pre-charged filters were used for removing particulate matters and gas absorbers are packed between two layer filters for removing gases pollutants such $CO_2$, VOCs and HCHO. Urban subway has characteristics about proper clean air flow, must be installed in narrow space and maintenance cycle has enough time. SCAP prototype is producted as all in one method which decrease fine dust, $CO_2$ and noxious gas. and basic test carry out with quantity of wind, a gap of pressure, sampling efficiency.

• Proceedings of the KSR Conference
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• 2007.11a
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• pp.1777-1782
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• 2007

Since July in 2004, starting with urban bus reorganization of Seoul metropolitan government, the change of the public transportation which integrates the urban bus and the subway of the metropolis are being continued. But the integration of such bus and the subway is staying to only a fare system mainly, and the guidance system of the subway and the bus has not changed. So we propose the concept of the new guidance system following public transportation change tendency. At first we introduce the new information system which can guide city railroad and bus altogether, and we propose new system which can guide divided by the trunk line and the branch line instead of bus and subway. Last high-functional guidance system which can give passengers tip and hint for various and effective usage of public transportation in more complicated city transit network is introduced. This new guidance system can increase competitiveness of public transportation system and stretch transportation share of it. And that guidance system is high-class contents that all public transportation business can utilize, so it can originate new industry. In conclusion, this new innovative guidance system is important field that government, local administration and public transportation business must be concerned and develop.

• Proceedings of the KSR Conference
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• 2006.11b
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• pp.941-946
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• 2006

It followed in system development and SMRT(Seoul Metropolitan Rapid Transit Co)System reached to an automatic train operation(ATO) and driverless operation(DLM) from the manual operation due to the train driver. The train like the general bus or the car vehicle was not serial riding in a car and the Parallel concept which the numerous passenger rides in a car simultaneously occur frequently the charge of the train driver unmanned bitterly from existing manual handling was a possibility of doing, train open door control(ODM) which bites also ATO, it handles it minimized. Like this ATO/DLM, the control system which bites being a Wayside to Train communication for immediacy, it is a system of the Vital concept the immediacy of the citizen Data evil the radio information transmission and the train of the interface which is accurate from unmanned operation and, will decipher, will accomplish it will guarantee. It respects the passenger accident prevention and an air question environment improvement from subway platform and phul leys the screen door of Platform(PSD) with the fire tube frost it refers and part it treats and to sleep it does, ODM which bites is accuracy and immediacy of altitude and when seeing from the viewpoint which demands the trust of altitude, ODM system the trust of car incest interface in the equipment construction which is safe and the comparative analysis back of the system analysis against the control which bites and case study and other subway system it leads from the research which it sees and signal - train in base grudge to sleep it contributes it does.

• Journal of the Korean Society of Safety
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• v.28 no.3
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• pp.23-28
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• 2013

This study focuses on finding ways to derive train's optimal ECO driving pattern, which can improve the ride quality and reduce driving energy consumption with keeping the time interval between the stations. As research method, we compared difference of currently operating train's ATO and MCS driving patterns, and concentrated upon the things need to consider in simulation in order to improve the existing pattern of ATO driving pattern's issues with securing the train operation safety. Determining driving pattern minimizing energy consumption by controlling powering within speed limit and controlling switching to coasting at appropriate point considering the track conditions for each section, and determining braking control starting time considering ride comfort and precise stopping is considered to be most important.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.6
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• pp.1069-1073
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• 2016

The current free-riding subway system for the elderly over 65 years old has been implemented since in 1980. As the aging population increases, the number of free riders also increases. It results eventually in the increase of subsidy from government. In addition, a transfer between subway and bus is not good enough since the free ride system is applied to only subway not to bus. The aim of this study is to analyze the transport card data to understand the impact of free-riding in the viewpoint of economic issues. It aims also to analyze the transfer patterns between public transport. At the end it compares Korea case with international cases and finds out some issues on free-ride systems. Finally, counter-measures aimed at improving the current free-rider system is suggested.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.6
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• pp.1083-1091
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• 2016

This research uses public transportation card data to analyze the inter-regional transfer times, transfer frequencies, and transfer resistance that passengers experience during transit amongst the metropolitan public transportation modes. Currently, mode transfers between bus and rail are recorded up to five times during one transit movement by Trip Chain, facilitating greater comprehension of intermodal movements. However, lack of information on what arises during these transfers poses a problem in that it leads to an underestimation of transfer resistances on the Trip Chain. As such, a path choice model that reflects passenger movements during transit activities is created, which attains explanatory power on transfer resistance through its inclusion of transfer times and frequencies. The methodology adopted in this research is to first conceptualize the idea of metropolitan public transportation transfer, and in the case that mode transfers include the city-rail, to newly conceptualize the idea of transfer resistance using transportation card data. Also, the city-rail path choice model within the Trip Chain is constructed, with transfer time and frequency used to reevaluate transfer resistance. Further, in order to align bus and city-rail station administrative level small-zone coordinates to state and regional level mid-zone coordinates, the big node methdod is utilized. Finally, case studies on trip chains using at least one transfer onto the city-rail is used to determine the validity of the results obtained.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.3
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• pp.493-500
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• 2017

Based on the data accumulated through EMU fault management, this paper examines the reliability of old railway car parts and proposes measurements to improve safety. Subway Line 7 of the Seoul Metropolitan Rapid Transit Corporation, auxiliary power unit (Static Inverter) of the EMU second version is a core equipment to supply power to various room-service units in cars and make an effect directly on passenger satisfaction. To analyze the pattern of failure throughout the field data over a long period of time, this analysis of statistics and reliability considers the operating environment and stress factors. This statistical analysis presents the correlation between failure and the temperature stress factors related to frequent failure occurring intensively in summer. In addition, throughout the analysis of the life of the IGBT inverter, the effect of the temperature stress factor was observed before and after the repair. As a result of an analysis of the optimal operating conditions considering two variations of EMU, such as variable load and outside temperature, a difference in the cooling capacity between the optimal operating conditions and frequent failure conditions was observed. Based on this analysis, this paper suggests a way to minimize cooling capacity difference for the optimal operational conditions.

• Journal of Korean Society of Transportation
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• v.26 no.1
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• pp.25-35
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• 2008

The ridership and transit systems are influenced by the expansion of metro-rail in Seoul metropolitan area. However, it has been difficult to measure its precise quantitative influences. Also effective policy implementations have been limited due to the lack of practical evidences. Thus an empirical analysis for an operating metro-rail is essentially required. In this regard, this study examines the impact of the Jungang line on transportation system, whose metro-rail block has been recently started new service. The main interest of this study is to find out the changes of ridership and to forecast the ridership changes by the metro-rail service. The results indicate that the effect on auto users is less than that of bus users. The auto demand is decreased by 33.3% and the bus demand by 66.6%. Additionally, its influence on Gyeonggi-do bus was greater compared with that on the Seoul bus. From questionnaire survey, this results could be confirmed. To sum up, the metro-rail gives less influences on auto users, while it gives greater influences on bus users.