• Journal of the Korean Society for Railway
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• v.2 no.1
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• pp.28-37
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• 1999

Many residential areas are situated near to railroad tracks so that a railroad noise has been one of the major environmental issues. In this paper two important aspects have been investigated in order to properly evaluate the railroad vehicle noise : sound power levels for different types and sound propagation characteristics of the railroad vehicles. For noise source characteristics of railroad vehicles, sound power values for various types of trains that are in active service have been measured. In this paper, domestic railroad vehicles are measured and compared with high speed train(TGV). Based on sound power information of railway vehicles, prediction on the sound pressure level and equivalent noise level near to railway areas have been evaluated.

• Journal of the Korean Society for Railway
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• v.16 no.1
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• pp.14-19
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• 2013

Because excessive interior noise when riding a high-speed train leads to annoyances, fatigue and stress for passengers, interior noise reduction methods should be considered. In particular, a high-speed train operated in various operation environments, and in South Korea, these include open fields and tunnels. Therefore, a specific study about changes in interior noise characteristics according to different environments is necessary. For this reason, the interior noise characteristics on a KTX train and on the KTX-Sancheon train were analyzed from noise measurements using microphones in this paper. Vibrations on the axles, bogies and floor were also measured, are these area are structural paths for interior noise. From this research, the interior noise characteristics according to the driving speed were deduced and the effects on interior noise by driving environments such as open fields and tunnels were investigated. Furthermore, the effect on interior noise by axles, bogies and floor vibrations were analyzed from a transfer function analysis.

• International Journal of Internet, Broadcasting and Communication
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• v.14 no.3
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• pp.249-257
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• 2022

In recent years, if we order food by easily accessing the online market with our smartphone, we can receive the product in a fresh state at dawn the next day. Cold chain is an industry that can create high added value because it has both the characteristics of general logistics and sensitivity to temperature. Based on the electrical specifications derived from the reefer container capacity requirement investigation, we proved that power supply to up to 33 reefer containers can be made by using three additional auxiliary power supplies which are applied for freight trains in Korea. In this paper, we conducted a research on a design of power supply system for freight train reefer container based on simulation as a basic research necessary for low-temperature distribution and cold chain construction based on the reefer container railroad. Consequently, the simulation was conducted using the three-phase inverter diagram in PSIM and the SVPWM (3-harmonic injection method) control technique, and it was verified that the required power voltage was satisfied with 622V_dc, which is lower than the input voltage of general SPWM of 718V_dc. The details of this paper could be used as a foundational study for constructing cold chains based on a reefer container dedicated to freight trains in the future.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.64 no.4
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• pp.199-206
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• 2015

A rising attention is paid to the railway system in many countries. KOREA is also of the opinion that the railway has to play a more important role in the near future to face up to the problems that increase gradually in the transport sector. To attract more traffic to the rail networks, it is important for rail modes to have running time competitiveness. Tilting trains, where it is possible to tilt the car-body towards the center of the curve, are a less expensive alternative to shorten travelling times on existing lines. Running time for tilting train is one of the most important factors, with which passenger demand forecasting or economic feasibility analysis will be done. This paper evaluates the speed limitation of tilting train around curves and also presents calculation process of its simulated possible running time. Then the adequacy of estimated time is verified with running time for Korean protype tilting train TTX (Tilting Train eXpress) by actual test run. As a case study, the estimated running time for the production version of tilting train and its time saving are presented compared with 2012's conventional Saemaul trains and non-tilting trains on the Gyeongbu line in the Korean rail network.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.1689-1693
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• 2003

Communication based train control system is applied regularly worldwide. And this system may be used in domestic soon. Communication based train control system does not depend on conventional track circuit. Therefore, position and distance control of train to prevent collision with leading train may become important safety factor. This paper developed collision avoidance algorithm to control trains of several units efficiently for this. In developing a collision avoidance algorithm, it is desirable to avoid the need for additional system. Additional system restricts the development of the algorithm by limiting the effectiveness of the algorithm to only those areas where the additional system can be afforded and has been installed.

• Proceedings of the KIEE Conference
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• 2003.11a
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• pp.205-209
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• 2003

Computerized simulation is becoming an indispensable procedure in the stage of planning, design, and operation of railway systems. This paper presents result of simulation technique for describing electrical performance of the power supply system which comprises the substation, catenary, feeder, and rails where multiple trains are running using result of train performance simulation.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.1333-1337
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• 2003

The present headway on KNR lines varies from 6 to 10 minutes. Therefore, KNR would like to reduce the headway of all the lines by 4 minutes with the implementation of ERTMS/ETCS on-board system. In Korea, thanks to the operation of the High Speed Line in 2004, the bottleneck phenomenon will occur only in a few sections such as Seoul-Siheung, which will be the common route between KTX and conventional trains. Therefore, we will analyze expected braking distance and running time depending on characteristics of conventional passenger and freight trains and high speed train will be operated within electrified conventional line for comparing the headways of ATS trackside and ETRMS/ETCS on-board system within the Seoul-Siheung section.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.189-194
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• 2007

To reduce the cost and time of transport in Eurasian railroad networks such as TKR, TCR and TSR owing to the problem of different track gauges(narrow/standard/broad gauge), it is important to develop the gauge - adjustable wheelset system to adapt easily to these gauges. Moreover, freight trains having the gauge - adjustable wheelset will be run various curved tracks in railroad networks. Therefore, to assure the safety of the gauge-adjustment wheelset system, it is necessary to evaluate integrity of locking parts in the system using stress analysis. In this study, it was performed to contact stress analysis of locking parts by using FEA(finite element analysis) simulator during the gauge changeover operation and freight trains' service in the curved track, respectively.

• Proceedings of the KIEE Conference
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• 2005.07b
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• pp.1604-1606
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• 2005

Tilting train has been developed to increase the operational speed of the trains on conventional lines which have many curves. This train are tilted at curves to compensate for unbalanced carbody centrifugal acceleration to a greater extent than compensation produced by the track cant, so that passengers do not feel centrifugal acceleration and thus trains can run at higher speed at curves. This paper show that results of normal capacity calculations of the electrical equipments such as Main transformer, PWM converter, VVVF inverter, traction motor in TTX(tilting train express) with maximum operation speed 180 km/h

• Journal of Institute of Control, Robotics and Systems
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• v.22 no.2
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• pp.162-169
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• 2016

Gyeong-bu railway line in Korea between Seoul and Cheon-an was built as two double tracks. A four-display signaling system, only for the metro line, was installed on the second double track so KTX and conventional trains can only operate on the first double track. This study suggests a method to allow KTX and conventional trains operated on the five-display signaling system to respond to accidents and track defects on the second double-track under the four-display signal system by means of problem analysis, calculation of breaking distances for KTX and conventional trains at each break mode, and improvement of the ATS system.