• Proceedings of the KSR Conference
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• 2002.10a
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• pp.367-375
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• 2002

In this paper the cases in developed countries on how to deal with the accident/incident for high-speed train crew, and their training and exercises for filed application will be reviewed, and the plan on how to deal with accidents/incidents for crew, which is helpful for preparing the high-speed railway operation in Korea and it's safety, will be presented.

• Nuclear Engineering and Technology
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• v.26 no.1
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• pp.1-8
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• 1994

The flame speed correlation considering thermal-hydraulic phenomena under severe accidents is proposed and correction coefficients are defined. This correlation modifies the pressure dependency in Iijima-Takeno correlation and adds the steam suppression effects to it in the anticipated hydrogen and steam concentration ranges under severe accidents. The existing models of flame speed due to hydrogen combustion under severe accidents are based on the experiments which were performed merely at room temperature and atmospheric pressure. They have difficulty in predicting a accurate flame speed in a case of high temperature and pressure during severe accidents. Thus the flame structure is assumed as a prerequisite to the reliable determination of flame speed and theoretical model is developed. To examine the validity, flame speeds in various conditions calculated by this model are compared with those obtained by the calculation of the existing correlations of the codes such as improved HECTR and MAAP. Also the steam suppression ratio is quantified and the steam suppression coefficient is defined as a composition of mixture. Initial temperature and pressure dependencies are investigated and correction coefficents are determined. More experimental studies can be recommended to improve this correlation to its further works.

• Journal of the Korea Safety Management & Science
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• v.26 no.2
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• pp.55-64
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• 2024

As the distribution of vehicles and logistics increases due to the development of human civilization and the increase in population, various roads play an important role in domestic traffic and transportation. However, the recent emergence of large cities and new cities is causing traffic problems, and the increase in roads is inevitable for the smooth distribution of vehicles and logistics. In Korea, mountainous regions occupy 70% of the country, so tunnels are used to open roads. Without this, it is difficult to open the road. Currently, there are 3,720tunnels (as of December 31, 2023) installed on high-speed national highways, general national highways, and local roads nationwide, with a length of 2.499 and increasing every year. Accordingly, fire accidents in tunnels will also increase, and due to the nature of tunnel fire accidents, there is a high probability that they will escalate into large-scale disasters, resulting in casualties and property damage, as well as significant social losses due to the disruption of logistics transportation, etc. As the possibility of potential hazards is increasing, the purpose of this study is to build a safe and efficient tunnel system by optimizing maintenance and management for fire and disaster accidents in tunnels.

• Proceedings of the KSR Conference
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• 2006.11b
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• pp.1461-1467
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• 2006

In case of accidents at the line of Seoul-Pusan high speed railway, high speed train should be operated with making a detour by using existing Seoul-Pusan railroad. For Dae-jeon$\sim$Dae-Gu section which has fragile structures, following points are investigated. In operating existing train, train running time is analyzed by the case of only high speed train being in service and the case of high speed train being in service on condition that existing train is operated. Also the possibility about operation on present train headway and train headway that is applicable to operation and vocational problems would be examined.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.20 no.6
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• pp.47-54
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• 2021

The number of freeway traffic accidents in Korea is about 4,000 as of 2020, and deaths per traffic accident is about 3.7 times higher than other roads due to non-recurring congestion and high driving speed. Most of the accident types on freeways are side and rear-end collisions, and one of the main factors is hazard traffic flow caused by merge, diverge and accidents. Therefore, the hazard traffic flow, which appears in a continuous flow such as a freeway, can be said to be important information for the driver to prevent accidents. This study tried to classify hazard traffic flows, such as the speed change point and the section where the speed difference by lane, using individual vehicle information. The homogeneous segment of speed was classified using spatial separation based on geohash and space mean speed that can indicate the speed difference of individual vehicles within the same section and the speed deviation between vehicles. As a result, I could extract the diverging influence segment and the hazard traffic flow segment that can provide dangerous segments information of freeways.

• Proceedings of the KSR Conference
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• 2004.06a
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• pp.328-333
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• 2004

Railway is huge traffic system which is operated organically combining all the elements; vehicle, track, electric power, signal/communication, operation, etc. Safety level has ben improved steadily by learning lessons from past accident. But with rapid progress in high-speed, massive, high-frequency transit fresh idea of accident prevention is now in order. In quest of effective and efficient countermeasure, we aim to establish an adequate safety evaluation/management method. Our proposals are basic concept relating to safety analysis of fatal accidents, AHP of Saaty, Fuzzy AHP.

• Proceedings of the KSR Conference
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• 2003.10a
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• pp.192-198
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• 2003

Railway is huge traffic system which is operated organically combining all the elements; vehicle, track, electric power, signal/communication, operation, etc. Safety level has been improved steadily by learning lessons from past accident. But with rapid progress in high-speed, massive, high-frequency transit fresh idea of accident prevention is now in order. In quest of effective and efficient countermeasure, we aim to establish an adequate safety evaluation/management method. Our proposals are basic concept relating to safety analysis of fatal accidents, AHP of Saaty, Fuzzy AHP.

• Journal of Korean Society of Transportation
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• v.26 no.3
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• pp.85-95
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• 2008

The purpose of this study is to reduce a high speed driving, it is a large scale traffic accident as the most dangerous fact on the highway. So traffic accidents related to high speed driving, a number of automated speed enforcement system has been established up to now. At present automated speed enforcement system in Korea control overspeed vehicle only in the specific spot. Because the drivers generally recognize the previous stated fact. therefore, we need speed control by new system. it is necessary to establish the automated traffic enforcement system based on the travel time speed. In conclusion, we obtain the desired results about automated traffic enforcement system based on the travel time speed. it is important that the number of traffic accidents has decreased and try to secure the safety of traffic.

• Proceedings of the KSR Conference
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• 2003.05a
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• pp.686-693
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• 2003

An intensive study was conducted for crashworthiness structural design of recently developed Korean High Speed Train. Two nam design concepts are setup to protect the both crews and passengers from serious injury at heavy collision accidents, and to reduce damages of the train itself at light collision accidents. For occupant protection a collision against a movable 15 tons rigid obstacle at 110 kph and a train-to-train collision at 30 kph were selected as accident scenarios for the heavy collisions based on the train accident investigations. A train-to-train collision at 8 kph was used for the light collisions. The crashworthiness behaviors of KHST have been evaluated numerically using the finite element method. Also, one-dimensional collision analyses show good crashworthy responses in a full rake consist and 3-dimensional shell element analyses do in the front-end structures of the power car. Occupant analyses and sled tests demonstrated that KHST performs well enough to protect occupants under the considered accident scenarios.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.1213-1220
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• 2008

In this study, the crashworthy design guidelines for the high speed EMU were derived and numerically evaluated. As for this high speed train, there are several different features from the KTX in that the conventional type bogies are adopted and the front end car (TC car) accommodates passengers. It is natural that the impact acceleration of the front end car should be controlled under the appropriate level stipulated at safety regulations for collision accidents. Also, car-to-car interfacing structures and devices should be deliberately designed to prevent overriding and telescoping mechanisms. As the first step for these design countermeasures, it was studied that how much impact energy should be absorbed at the energy absorbing zones and devices of each carbody to satisfy the impact acceleration regulations of the safety regulations. These results will be used as the crashworthy design guidelines for the high speed train in the next year research.