• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.12
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• pp.6018-6033
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• 2018

Fires are a common cause of catastrophic personal injuries and devastating property damage. Every year, many fires occur and threaten human lives and property around the world. Providing early important sign for early fire detection, and therefore the detection of smoke is always the first step in fire-alarm systems. In this paper we propose an automatic smoke detection system built on camera surveillance and image processing technologies. The key features used in our algorithm are to detect and track smoke as moving objects and distinguish smoke from non-smoke objects using a convolutional neural network (CNN) model for cascade classification. The results of our experiment, in comparison with those of some earlier studies, show that the proposed algorithm is very effective not only in detecting smoke, but also in reducing false positives.

• Journal of the Society of Disaster Information
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• v.16 no.1
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• pp.44-59
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• 2020

This study analyzed a gas explosion accident. A gas smell from a underground coffee shop in the two-story building was reported to 119. A fire brigade was turned out, turned off the main valve of LPG gas cylinder on the roof, and checked the turning off of middle valve in the coffee shop. The fire brigade required a gas supplier and gas installer who arrived at the spot to take safety actions. Gas explosion occurred seven minutes after the fire brigade was withdrawn and two people died and 21 people were injured. A court decided that because the causes for gas explosion were not found, compensation responsibility could not be charged with the gas supplier, the gas installer, or Korea Gas Safety Corporation. In this reason, the court judged that only the fire brigade who was withdrawn without taking safety actions shall compensate victims or bereaved families. Therefore, fire brigades who turn out after a 119 report of a gas leak should take safety actions such as escaping people or preventing people's access and ventilating and be withdrawn when there is no possibility of fire or explosion.

• International Journal of Aerospace System Engineering
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• v.9 no.1
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• pp.1-15
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• 2022

Pyrotechnic initiators provide a source of pyrotechnic energy used to initiate a variety of space mechanisms. Pyrotechnic systems build in electromagnetic environment that may lead to critical or catastrophic hazards. Special precautions are need to prevent a pulse large enough to trigger the initiator from appearing in the pyrotechnic firing circuits at any but the desired time. The EMC verification shall be shown by analysis or test that the pyrotechnic systems meets the requirements of inadvertent activation. The MIL-STD-1576 and two range safeties, AFSPC and CSG, require the safety margin for electromagnetic potential hazards to pyrotechnic systems to a level at least 20 dB below the maximum no-fire power of the EED. The PC23 is equivalent to NASA standard initiator and the 1EPWH100 squib is ESA standard initiator. This paper verifies the two safety margins for electromagnetic potential hazards. The first is verified by analyzing against a RF power. The second is verified by testing against a DC current. The EMC safety margin requirement against RF power has been demonstrated through the electric field coupling analysis in differential mode with 21 dB both PC23 and 1EPWH100, and in common mode with 58 dB for PC23 and 48 dB for 1EPWH100 against the maximum no-fire power of the EED. Also, the EMC safety margin requirement against DC current has been demonstrated through the electrical isolation test for the pyrotechnic firing circuits with greater than 20 dB below the maximum no-fire current of the EED.

• Journal of the Korean Institute of Gas
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• v.16 no.3
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• pp.22-28
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• 2012

For a methanol separation column of the BPA (Bisphenol A) plant, HAZOP (hazard and operability) assessment was performed and damage ranges were predicted from the accident scenarios for the fire and the explosion. As a result, the damage range of the jet fire was 20 m in the case of rupture of the discharge pipe (50 mm diameter) of safety valve, and that of the flash fire was 267 m in the case of catastrophic rupture. Also, the damage ranges of the unconfined vapor cloud explosion (UVCE) for the rupture of the discharge pipe and for the catastrophic rupture were 22 m and 542 m, respectively. For the worst case of release scenarios, safety measures were suggested as follows: the pressure instruments, which can detect abnormal rise of the internal pressure in the methanol separation column, should be installed by the 2 out of 3 voting method in the top section of the column. Through the detection, the instruments should simultaneously shut down the control and the emergency shut-off valves.

• Fire Science and Engineering
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• v.26 no.5
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• pp.13-20
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• 2012

Many fire-fighters suffer from the burn injuries, and the severe burns are the most catastrophic injury a person can survive, resulting in pain, emotional stress, and tremendous economic costs. It is important to understand the physiology of burns for prevention from skin burns and a successful treatment of a burn patient. But a few researches have been presented because the complex physical phenomena of our inside body like non-linearity characteristics of human skin make them difficult. Thus in this study, thermal analyses of biological tissues exposed to a flash fire causing severe tissue damage were studied by using a finite difference method based on the Pennes bio-heat equation. The several previous models for skin thermo-physical properties were summarized, and the calculated values with those models of tissue injury were compared with the results obtained by the previous experiment for low heat flux conditions. The skin models with good agreement could be found. Also, the skin burn injury prediction results with the best model for high heat flux conditions by flash flame were suggested.

• Fire Science and Engineering
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• v.17 no.3
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• pp.61-73
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• 2003

Most of the accidents occurred from the chemical plants are related to the catastrophic gas release events when the large amount of toxic materials is leaked from its storage tank or transmitting pipe lines. In this case, the greatest concerns are how the spreading behaviors of leakages are depended on the ambient conditions such as air stability and other environmental factors. Hence, we have focused on the risk assessments and consequential analysis for chlorine as an illustrative example. As appeared in the result, Fire & Explosion Index depicted it a bit dangerous with presenting the comprehensive degrees of hazard 90.7. And as a result of Phast6.0/ALOHA, the trends of each scenario appeared considerably identical although there are some differences in the resulting effects according to the input data for the Gas Model. The consequence analysis is performed numerically based on the dense gas mode. In the future, using more correct input data, material properties, and topographical configuration, the method of this research will be useful for the guideline of the risk assessment when the release of toxicants breaks out.

• Fire Science and Engineering
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• v.28 no.6
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• pp.82-89
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• 2014

Disasters that destroy homes and infrastructure and cause significant financial damage are becoming more common as population centers grow. In addition, several natural disasters have resulted in a major loss of life and created countless refugees due to damage to housing. After major catastrophic disasters, it is very important that the government agencies respond to post-disaster housing issues and provide resources such as temporary housing before the full rehabilitation and reconstruction of destroyed and damaged housing. To provide affordable temporary housing for residents who may lose their homes as the result of a catastrophic disaster including storms, government agencies must develop a post-disaster housing prototype. In general, government agencies should explore several different forms of factory-built single-story, single family housing, such as modular homes, panelized homes, and precut homes. In urban cities including New York and Seoul, it is very important to provide housing which supports the demand for higher-density living spaces than single-family homes or trailers typically available due to the high population density and the desire to resettle as many residents as possible in their former neighborhoods. This study identified the urban post-disaster housing prototypes that may provide higher density housing with high quality living spaces, high air quality, and energy efficiency as well as rapid deployment. A case study of "Urban Post-Disaster Housing Prototype Program in New York" was conducted through a detailed interview process with a designer, engineer, contractor, the Office of Emergency Management (OEM) in New York, the U.S. Army Corps of Engineers (USACE), and temporary occupants. An appropriate disaster housing program that can provide living spaces for victims of disasters that keeps residents in their community and allows them to live and work in their neighborhoods was developed.

• Journal of the Korean Society of Safety
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• v.14 no.4
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• pp.120-125
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• 1999

This study evaluated the effect of the accidents caused by fire, explosion, and toxic gas release by using SuperChems, quantitative hazardous material release modeling software, which estimates the potential area of damage. According to the loss severity, the appropriate risk management principles can be applied. Risk management is divided into the two methods which are risk control and risk financing. Risk control includes risk avoidance, risk spreading and diversification, and risk reduction. Risk financing includes risk retention and risk transfer. The results of this study can help the related company determine the appropriate reserve fund and the amount to be insured against the third party losses according to the estimated loss severity.

• Proceedings of the KSR Conference
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• 2007.11a
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• pp.1858-1863
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• 2007

Railway systems are one of the best mass transit systems and many people have prevented incidents/accidents and reduced fatalities remarkably. Especially we have tried analyzing and finding the measures to prevent catastrophic accidents like train collision, derailment and fire because of their severities. It is important to assess the safety performances of railway systems like crash-worthiness analysis, body, derailment affecting factor analysis and so on for reducing and finding out the reasonable causes of disastrous accidents. In this paper the refined top-level system requirements to build-up national infra for assessing railway safety performance and the procedures and methodology for reviewing, verifying and validating infra requirements are explained. Basically the authors have used system engineering processes to analyze and verify the requirements and installation procedures and have tried maximizing the practicality of the various safety assessment systems.

• Journal of the Korean Society for Railway
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• v.6 no.3
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• pp.156-162
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• 2003

Due to almost all tracks of new Kyoungbu high-speed lines(HSL) consisting of bridges and tunnels, HSR operational safety management is very important factor for passenger safety and preventing catastrophic event. Especially, it is important to approach the scene of the accident and assist in saving lives as soon as possible under emergency conditions. Therefore it is essential to prepare access methods and available resources in advance in order to support emergency correspodances promptly and effectively. This paper persents an application of geographical information system(GIS) for developing emergency management system as well as batabase system on tracks and facilities, electric/communication equipment and safety equipment required to support emergencies. The on-site information on the proximity of HSL is expressed on the numerical map, which can be helpful to call external supports such as medical service, local authorities, police offices, fire brigades, and etc. for the emergency situations.