• Proceedings of the KSR Conference
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• 2008.06a
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• pp.343-352
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• 2008

Safety-critical systems related to the railway communications are currently undergoing changes. Mechanical and electro-mechanical devices are being replaced by programmable electronics that are often controlled remotely via communication networks. Therefore designers and operators now not only have to contend with component failures and user errors, but also with the possibility that malicious entities are seeking to disrupt the services provided by theirs systems. Recognizing the safety-critical nature of the types of communications required in rail control operations, the communications infrastructure will be required to meet a number of safety requirements such as system faults, user errors and the robustness in the presence of malicious attackers who are willing to take determined action to interfere in the correct operation of a system. This paper discusses the safety strategies employed in the railway communications and proposes a security mechanism for Korean railway communication system. We present the developed communication safety evaluation tool based on the proposed security mechanism and also evaluate its protecting capability against the threats of masquerading, eavesdropping, and unauthorized message manipulation.

• Proceedings of the KSR Conference
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• 2004.06a
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• pp.392-396
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• 2004

The number of parameters and the number of samples are the key point of trans-log cost function which studied recently. Most of models show that the number of parameters is more than the number of samples. Therefore, these studies gave unreliability of the estimation results. First, we surveyed theoretical cases and researches for the formulation of cost function of railroad industry. Second, we will suggest trans-log cost function by analyzing cost data of KNR. And, the cumulative data will be needed for the confidence of estimation results.

• Proceedings of the KSR Conference
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• 2004.10a
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• pp.1765-1769
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• 2004

The number of parameters and the number of samples are the key point of trans-log cost function which studied recently. Most of models show that the number of parameters is more than the number of samples. Therefore, these studies gave unreliability of the estimation results. First, we surveyed theoretical cases and researches for the formulation of cost function of railroad industry. Second, we will suggest trans-log cost function by analyzing cost data of KNR. And, the cumulative data will be needed for the confidence of estimation results.

• Journal of the Korean Society for Railway
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• v.9 no.5 s.36
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• pp.550-554
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• 2006

In the early stage of operation of KTX, passengers complained of the excessive cabin noise as the passes the tunnel. The noise is caused partly by wheel-rail contact and partly by airflow around the carbody. In this study, to reduce the cabin noise, the effect of the mud-flaps located between the cars is investigated. A series of tests was conducted to clarify the influences of the type and length of mud-flap, and train speed on the cabin noise. The optimum length of mud-flap was found. The shedding vortices around the mud-flap is thought to be the cause of the aerodynamic noise. Strouhal number and the resonant shedding frequency around the mud-flap correlated well with the cabin noise level.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.05a
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• pp.1221-1226
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• 2001

A structure gauge assessment is needed to ensure that a railway vehicle can run safely along a length of track without coming unacceptably close to lineside structures or equipment, or to vehicles running on adjacent tracks. This apparently straightforward question is in reality very complicated. The amount of space required for the safe passage of a railway vehicle is significantly greater than its static body profile for a number of reasons as follows: as the vehicle runs along the track, the track input excites the vehicle and it moves on its suspension. On curved track its geometric position leads to curve overthrows. A number of different approaches have been used to answer this question and some are described and specially applied to urban train by computer simulation in this paper. The program used for calculating the kinematic and swept envelope is the VAMPIRE made in U.K.

• Journal of The Korea Institute of Healthcare Architecture
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• v.20 no.2
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• pp.27-35
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• 2014

Purpose: The number of the transportation poor has been steadily increased, and also the social perspective toward the disabled has been changed. Thus, Universal Design has been needed. In particular, the unknown majority of the transportation poor have frequently used the urban railway facilities which should reflect the ideals and principles of Universal Design. However, previous research has not focused on the study on critical factors of Universal Design. Based on this observation, the present study aims to find out Universal Design critical factors of urban railway station. Methods: This study explores the criteria of planning Universal Design in the urban railway station by analyzing and comparing the similar criteria used in both domestic areas and foreign countries. Result: Findings from this study are as follows. First, we found out the critical factors of Universal Design in the urban railway station by comparing and analyzing the similar criteria previously used. Second, this study also suggests the better directions toward the domestic criteria relating to the urban railway system. Third, we found the need of the universal standard as well as individually corresponding strategy. Moreover, we found the need of preparing the critical factors for the physical environments as well as the human service. Implications: The further research on findings of the planning criteria will have been continued on the basis of findings of the present study.

• Journal of Korean Society of Transportation
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• v.31 no.2
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• pp.80-89
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• 2013

The purpose of this research is to optimize the line planning of the intercity passenger railway. In this study, the line planning problem has been formulated into a mixed integer programming by minimizing both user costs (passenger's total travel time) and operator costs (operation, maintenance and vehicle costs) with multiple train types. As a solution algorithm, the branch-and-bound method is used to solve this problem. The change of travel demand, train speed and the number of schedules have been tested through sensitivity analysis. The optimal stop-schedules and frequency as well as system split with respect to each train type have been found in the case study of Kyoung-bu railway line in Korea. The model and results of this research are useful to make a decision for railway operation strategy, to analyze the efficiency of new railway systems and to evaluate the social costs of users and operators.

• Journal of Korean Society of Steel Construction
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• v.22 no.1
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• pp.13-20
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• 2010

Seismic risk assessment of railway bridges is an important issue for a transportation network, because loss of functionality of railway bridges could result in severe disruption of the railway line, as no redundant routing systems generally exist. Although many studies have been conducted by numerous researchers regarding fragility analyses of bridge structure, little or no studies have been done for fragility analyses of a class of bridge structures considering their geometric variability. This study performs a fragility analysis for Track-on Steel-Plate-Girder (TOSPG) railway bridges in Korea considering their span variability. Seismic fragility curves are developed for a series of bridges with different spans varying from 2 to 15. At last, the fragility curves for the whole TOSPG bridges in Korea are also developed using the total probability theorem. This study is expected to effectively contribute to the seismic risk assessment of railway lines, where a number of bridges are present.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.16 no.1
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• pp.64-77
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• 2017

Domestic railway station calculates average number of passenger per day by considering future regional society and development of industrial economy etc, is carrying out designs on railway station scale. However, problems are being suggested situationally because selected average passenger data does not consider passengers having been diversified for a year. For representative example, confusion of Gwangju-Songjeong Railway Station got worse due to passengers whose number is more than original plan since the opening. Therefore, this study quotes the concept of design hourly factor using in designing roads to consider passengers having been diversified for a year in railway field. In order to calculate factor, collecting railway passenger data and also estimate, reliability verification were executed by using exponential model and 3rd equation model. As a result of deducing design hourly factor through inflection point calculation, utilizing exponen tial model is analyzed to well reflect the value of design hourly factor on railway passengers.

• Journal of Korean Society of Transportation
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• v.25 no.3
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• pp.77-85
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• 2007

The number of accidents occurring at railway crossings is less than the accidents on other sections of roads but they cause enormous socio-economic damages. The geometric aspects of the railway crossing have to allow the drivers to recognize the crossings and take precautions against collisions. Therefore, ensuring visibility for the vehicle approaching the railway crossing is necessary for safe operation of the crossing. However, as there is little research related to railway crossing visibility in Korea. validating visibility and maintaining visibility based on the validation is badly needed. This research develops a visibility validation model to support improving visibility and to reduce accidents at railway crossings to improve safety for the crossing users.