• Journal of Platform Technology
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• v.9 no.3
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• pp.44-51
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• 2021

In general, golden time refers to the most important time in the initial response to accidents such as saving lives or extinguishing fires. The golden time varies from disaster to disaster, but is aimed at five minutes in terms of fire and first aid. However, for the actual site, the average dispatch time for ambulances is 9 minutes and the average transfer time is 17.6 minutes, which is quite large compared to the golden time. There are various causes for this delay, but the main cause is traffic jams. In order to solve the problem, the government has established emergency car concession obligations and secured golden time to prioritize ambulances in places with the highest accident rate, but it is not a solution in rush hour when traffic is increasing rapidly. Therefore, this paper proposed a deep learning-based emergency vehicle priority signal system using collected sound data by installing sound sensors on traffic lights and conducted an experiment to classify frequency signals that differ depending on the distance of the emergency vehicle.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.6
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• pp.689-695
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• 2018

This paper presents the means of controlling the regeneration of a diesel particulate filter (DPF) that is mounted on tactical vehicles to satisfy exhaust gas standards. The DPF captures particulate matter in the exhaust gas and combusts the captured particulate matter. This process is regeneration, which is essential to the normal performance of the DPF. Bad regeneration causes degradation of vehicle performance; worse, it can lead to a vehicle fire. DPF regeneration is performed by control logic. If the regeneration control logic does not properly reflect the operating characteristics of the vehicle, DPF regeneration may not occur. Consequently, it is very important to ensure the DPF operates properly by reflecting the operating characteristics of the tactical vehicle. This study analyzes the operational characteristics of a tactical vehicle and the DPF, and adds proper DPF regeneration control logic. Additionally, this study is intended to simultaneously improve the additional problems that may occur from operating under the added regeneration control logic.

• Journal of Korean Tunnelling and Underground Space Association
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• v.8 no.1
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• pp.53-63
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• 2006

The objective of this study is to analyze the smoke movement and the smoke extraction efficiency using by the partial extraction system for case of tunnel fire. Based on Froude modeling and isothermal model, the 1/20 scaled model tunnel (12m long) was constructed. In the case of the upper critical velocity in the main tunnel, the smoke extraction efficiency shows almost same between group damper and distributed damper. Finally, if the fire occurs on a traffic Jam in a tunnel, it is proposed that the open dampers in partial gallery extract smoke from the main tunnel without jet fan operation. Then, after the passengers have escaped the tunnel, the jet fans work on. On the other hand, If the traffic is uncongested in the tunnel, the jet fans (smoke control system) and partial extraction system (smoke exhaust system) are operated at once in tunnel fire.

• Journal of the Korea institute for structural maintenance and inspection
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• v.14 no.3
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• pp.118-122
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• 2010

The study presents a standard time-temperature curve to evaluate the fire performance of subway tunnel structures. The central subway section is 135km long in Korea, the fourth longest in the world. The number of subway tunnels has been increasing rapidly and fire risk is proportional to the tunnel length. However, an adequate time-temperature curve for subway tunnel fires does not exist. Therefore, we studied a proposed foreign fire design model for which the heat rate is based on the traffic, and we present an appropriate time-temperature curve for Korean subway tunnels. The ISO 834 curve was used as a fire design model and the temperature distribution in the tunnel was estimated using numerical analysis. This led to a proposal for effective measures against subway tunnel fires.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.19 no.6
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• pp.1-13
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• 2020

In the event of fire, it is necessary to put out the fire within a golden time to minimize personal and property damages. To this end, it is necessary for fire engines to arrive at the site quickly. This study established a fire engine travel time estimation model to secure the golden time by identifying road and environmental factors that influence fire engine travel time in the case of fire by examining data on fire occurrence with GIS DB. The study model for the estimation of fire engine travel time (model 1) covers variables by applying correlation analysis and regression analysis with dummy variables and predicts travel time for different types of places where fire may occur (models 2, 3, 4). Analysis results showed that 17 siginificant independent variables are derived in model 1 and the fire engine travel time differs depending on the types of places where fire occurs. Key variables(travel distance, number of lane, type of road) that are included commonly in the 4 models were identified. Variables identified in this study can be utilized as indicators for research related to travel time of emergency vehicles and contribute to securing the golden time for emergency vehicles.

• International Journal of Highway Engineering
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• v.13 no.4
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• pp.199-209
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• 2011

In the study of traffic safety, the analysis on factors affecting crash severity and the understanding about their relationship is important to be planning and execute to improve safety of road and traffic facilities. The purpose of this study is to develop a hierarchical binomial logistic model to identify the significant factors affecting fatal injuries and vehicle damages of traffic crashes on freeway. Two models on death and total vehicle damage are developed. The hierarchical structure of response variable is composed of two level, crash-occupant and crash-vehicle. As a result, we have gotten the crash-level random effect from these hierarchical structure as well as the fixed effect of covariates, namely odds ratio. The crash on the main line and in-out section have greater damage than other facilities. Injuries and vehicle damages are severe in case of traffic violations, centerline invasion and speeding. Also, collision crash and fire occurrence is more severe damaged than other crash types. The surrounding environment of surface conditions by climate and visibility conditions by day and night is a significant factor on crash occurrence. On the orher hand, the geometric condition of road isn't.

• Journal of the Korean Institute of Gas
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• v.13 no.6
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• pp.15-20
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• 2009

The number of compressed natural gas (CNG) vehicles have increased gradually by virtue of korea government's urban air quality improvement policy since 1998. Although the use of CNG as transportation fuel gives environmental benefits, there is a possibility of huge accidents from unexpected fire. Therefore, needs for the guarantee of safety are indispensible for the reliable operation of CNG vehicles. A check valve is a safety device which prevents leakage of the pressurized fuel charged in a fuel tank. Durability of this component should be guaranteed in spite of repeated operation. This research has performed durability tests of a CNG check valve regarding the repeated usage, extreme chattering, and the effect of compressor oil.Although a check valve used for CNG vehicle satisfies validation requirements in the test results, it has been found that problem in the function of leakage prevention in a check valve could take place in the case of prolonged exposure to compressor oil.

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.441-445
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• 2008

LRT is eco-friendly transportation system and can be constructed at less than half cost of subway. Therefore many local governments have planned to construct a various type of LRT and some of them were already under construction. In Para. 2 of Art. 22 of the "Enforcement Decree of Urban Railroad Act" - safety standard of urban railroad vehicle, It can't be operated if "structures and devices" don't come up to standard required to safety operation. Constructor or operator should give an order or operate according to safety standard in Art. 3 of the Safety Standard of Urban Railroad Vehicle. Safety Standard of Urban Railroad Vehicle of 2000 was reformed once to tighten fire safety standard in 2004 after subway accident in Daegue. It was entirely made for medium and large-sized electric motor car. LRT, based on driverless operation and articulated bogie, has different safety standard in signalling devices and the axle load. etc. So many institutes related LRT have required to amend. In this paper, we described features of LRT vehicle and necessity of amendment and discussed how it should be amended.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.25 no.9
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• pp.1166-1175
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• 2021

We investigate the current situation and development trend of domestic smart city and emergency vehicle priority signal control system analyzing the existing effectiveness of 1) emergency vehicle priority signal control system and 2) control emergency vehicle priority signal, based on domestic and foreign prior research for signal control system security. The effectiveness of time reduction was analyzed through actual application and test operation to emergency vehicles after establishing the system. In addition, for security management and stable service of real-time signal system control we propose improvement for the technical control items of the ISMS-P certification system to secure golden time to protect citizens' precious lives and property in case of emergency by classifying and mapping the existing ISMS-P certification system and the Korea Internet & Security Agency's cyber security guide according to the items of security threats.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.32 no.5
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• pp.313-322
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• 2019

Recently, there have been frequent occurrences of bridge fires. Fires in cable-supported bridges can damage and brake cables due to high temperatures. In this study, fire scenarios that can occur on cable-supported bridges were set up. In addition, based on the results of vehicle fire tests, a fire intensity model was proposed and cable heat transfer analyses were performed on a target bridge. The analyses results demonstrated that temperature rises were identified on cables with a smaller cross-sectional area. Furthermore, vehicles other than tankers did not exceed the fire resistance criteria. When the tanker fire occurred on a bridge shoulder, the minimum diameter cable exceeded the fire resistance criteria; the height of the cable exceeding the fire resistance criteria was approximately 14 m from the surface. Therefore, the necessity of countermeasures and reinforcements of fire resistance was established. The results of this study confirmed that indirect evaluation of the temperature changes of bridge cables under fire is possible, and it was deemed necessary to further study the heat transfer analysis considering wind effects and the serviceability of the bridge when the cable temperature rises due to fire.