• Proceedings of the KSR Conference
• /
• 2006.11b
• /
• pp.231-237
• /
• 2006

Recently railroad industry pulls a new interest with stability, fixed time characteristic, low environment pollution characteristic and mass transportation characteristic. With industrial development railroad it joins in, The many research and regulation production are coming to do. Specially like this activities are coming to be advanced actively from North America and Europe. From viewpoint of railway car production company, The vehicle production that a suitable Europe standard is essentiality for find a Europe market that The whole vehicle consuming hold it does a most big specific gravity. From this study, developed finite element model for analysis technology about crashworthiness of inside GM/RT 2100 standard and analyzed crash results.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.63 no.1
• /
• pp.179-183
• /
• 2014

An electric railway is unique system that electric trains consumed huge electric power are travelled and is much interested with EMC. There were several problems exceeding the standard in the frequency range of 9 kHz to 150 kHz because the radiation noises were moved the higher frequency range according to developing the power electronic technology. It is studied the analytic simulation for reducing noise level in terms of cables of the electric train and is experimentally approved the reduction effectiveness.

• Journal of the Korean Society of Mechanical Technology
• /
• v.13 no.1
• /
• pp.11-16
• /
• 2011

When the trains are passed the station, a serious force is applied to ground and the caused vibration is propagated to the area of the station by the ground and rocks. The caused vibration brings about the operation interruption of the equipment which is sensitive to the vibration, or will bring about the structural damage of the station. In this study, to investigate the vibrational evaluation of railway station by the train service, the vibration simulation was performed and analyzed the effect of the vibration isolating countermeasure. From the vibration measurement, all trains that passed through the station exceeded the vibration criteria. Therefore, the vibration isolating countermeasure was established and the vibration simulation was performed.

• Proceedings of the KSR Conference
• /
• 1999.11a
• /
• pp.242-255
• /
• 1999

In order to manufacture high quality goods, the engineers who will design them has to have board technical experience as well as profound engineering knowledge. The engineers also be able to design and manufacture well development goods base on new advanced technology. Design process can be defined as transforming activity raw material into finished producted for human needs. The wealth of nation depend on its ability to retrieve natural resources and manufacture goods. Its ability, creation of goods, is most fundamental component of economic wealth of rich country. The rich countries have combine their own design knowledge with computer technology and create new effective design process. In this paper, one of the useful and practice design process created for railway industry is introduced. Base on the concept of this design process, the automatic wheelchair lifter design for railway vehicle is performed.

• Journal of The Korean Society For Urban Railway
• /
• v.6 no.4
• /
• pp.223-231
• /
• 2018

Since the introduction of PSD in 2005, the number of accidents involving passengers falling onto the tracks accidentally or intentionally have drastically decreased, but the number of PSD related passenger accidents is increasing. While existing papers on PSD have been devoted to systemic introduction and system improvement, papers on passenger casuality accidents due to deteriorated PSD have been limited. This paper proposes revising of the scenario model for passenger accidents using classified hazard sources of PSD.

• Journal of the Korean Society of Safety
• /
• v.38 no.4
• /
• pp.1-7
• /
• 2023

The steel wheels of urban railway vehicles gather a lot of data through regular measurements during maintenance. However, limited research has been carried out utilizing this data, resulting in difficulties predicting the maintenance period. This paper studied a machine learning model suitable for mileage prediction by studying the characteristics of mileage change according to diameter and flange thickness changes. The results of this study indicate that the larger the diameter, the longer the travel distance, and the longest flange thickness is at 30 mm, which gradually shortened at other times. As a result of research on the machine learning prediction model, it was confirmed that the random forest model is the optimal model with a high coefficient of determination and a low root mean square error.

• Journal of Information Technology Applications and Management
• /
• v.29 no.6
• /
• pp.63-80
• /
• 2022

In this paper, we study structural changes and performance gains in condition-based maintenance process redesign when mobile IoT technology is embedded into urban railway rolling stock. We first develop condition-based maintenance To-Be process model in accordance with the IoT deployment scheme. Secondly, we draw upon theoretical framework of redesign process analysis to develop performance evaluation method suitable to predictive maintenance shift from As-Is ordinary maintenance practice. Subsequently, To-Be process performance evaluations are conducted adopting both the quantitative and qualitative method for time, cost, and dependability dimensions. The results ascertain the considerable benefits captured through detection abnormality prior to actual rolling stock failure occurrence, and details of performance improvements and enhancement of standardization level is revealed. The procedures and results presented in this paper offers useful insights in the fields of IoT economic analysis, condition based maintenance, and business process redesign.

• Journal of the Korean Society for Railway
• /
• v.20 no.1
• /
• pp.11-19
• /
• 2017

Since operation of railway trains is a major source of particle pollution in tunnel air, a particle removal device can be an effective measure to remove wear particles. To obtain design conditions of the particle removal device that will be installed underneath the railway trains, the wind speed and particle concentration underneath the trains were investigated using a three-dimensional ultrasonic anemometer and a DustTrak aerosol monitor, respectively. The measurements were made for the trains running on Seoul Metropolitan Subway Line 5 on February 10, 2015. The data were analyzed according to the track geometry (straight, curved) and train speed pattern (acceleration, cruising, and deceleration) between stations. Train speed was also analyzed. The average wind speed and $PM_{10}$ concentration underneath the trains were ~30% of the train speed and ${\sim}200{\mu}g/m^3$ for both straight and curved sections. Average $PM_{10}$ concentration for deceleration sections was higher than that for acceleration sections.

• Proceedings of the KSR Conference
• /
• 2011.10a
• /
• pp.2860-2865
• /
• 2011

Recently, the number of passengers using urban railway has been increased by reasons of the reductions of car use due to high fuel prices and the enlightenment about the environment. Above all, the noise and the vibration coming from the friction between the wheel and the rail of trains in operation which is not only a factor that hinders riding comforts but causes civil complaints. Furthermore, the noise has become social issues from tightening the relevant regulations by the government since January 2010. Although ballasted tracks were constructed on urban railways at the time of opening, they have been changed into slab tracks because slab tracks require much less maintenance. However, in view of sound absorptivity of track, slab tracks have 10 times less capability than ballasted tracks(ballasted track : 0.5~0.6/slab tracks : 0.06) results more noise than that of ballasted tracks as much as 3dB(A) since slab tracks emit more reflection noise. Therefore, in order to minimize reflection noise on slab tracks, noise abatement system has been developed as a national R&D program to apply on-site test. It is assumed that the construction technology developed in this study can be used not only as basic data for the on-site test for the noise reduction in urban railway but as an efficient construction method.

• Structural Engineering and Mechanics
• /
• v.48 no.4
• /
• pp.455-466
• /
• 2013

In recent years, many countries have added railway noise to the issues covered by noise regulations. It is known that the rail is the dominant source of rolling noise at frequency range of 500Hz-2000Hz for the conventional speeds (<160km/h). One of the effective ways to reduce noise from railway track is using a rail vibration absorber. To study the acoustic performance of rail absorber, the decay rates of vibration have long been used by researcher. In this paper, A FE model of a periodic supported rail with infinite element in ABAQUS is developed to study the acoustic performance of the rail absorber. To compute the decay rates, acceleration responses along the rail transferred to MATLAB to obtain response levels in frequency domain and then by processing the response levels, the decay rates obtained for each1/3octav band. Continous rail absorber is represented by a steel layer and an elastomer layer. The decay rates for conventional rail and rail with one-side absorber and also, the rail with two side absorber are obtained and compared. Then, to improve the system of rail absorber, a steel plate with elastomer layer is added to bottom of the rail foot. The vertical decay rate results show that the decay rate of rail vibration along the track is significantly increased around the tuned frequency of the absorber and thus the rail vibration energy is substantially reduced in the corresponding frequency region and also effective in rail noise reduction.