• Journal of the Korean Institute of Gas
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• v.16 no.6
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• pp.87-101
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• 2012

In gas industries, the potential risks of serious accidents have been increased due to high technology application and process complexities. Especially, in case of gas-related accidents, the extent of demage is out of control since gas plants handle and produce combustible, flammable, explosive and toxic materials in large amounts. The characteristics of this kind of disaster is that accident frequency is low, while the impact of damage is high, extending to the neighboring residents, environment and related industries as well as employees involved. The hydrogen gases treated important things and it used the basic material of chemical plants and industries. Since 2000, this gas stood in the spotlight the substitution energy for reduction of the global warming in particular however it need to compress high pressure(more than 150 bar.g) and store by using the special cylinders due to their low molecular weight. And this gas led to many times the fire and explosion due to leak of it. To reduce these kinds of risks and accidents, it is necessary to improve the new safety management system through a risk management after technically evaluating potential hazards in this process. This study is to carry out the quantitative risk assesment for hydrogen filling plant which are very dangerous(fire and explosive) and using a basic materials of general industries. As a results of this risk assessment, identified the elements important for safety(EIS) and suggested the practical management tools and verified the reliability of this risk assessment model through case study of accident.

• Fire Science and Engineering
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• v.28 no.4
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• pp.1-7
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• 2014

Several complex devices and equipments are installed in the car's engine room, including various kind of oils or other flammable materials. So re-ignition is very likely to take place in it. In addition, it is restrictive for the driver or the occupant to open the bonnet and to spray the fire extinguisher in the engine room due to the high possibility of explosion. Therefore, a fire extinguishing system, which can detect a fire and inject the fire extinguishing agent to extinguish it, and fire extinguishing agents including HFC-227ea, which can stand the high temperature within the engine room and hold the viscosity sufficient to keep it in the kind of foam, were developed and tested. And the suffocation effect and the cooling effect come from the fire extinguishing principle of the foam fire extinguishing agent and the inhibiter catalyst effect come from the one of HFC-227ea was led simultaneously, and fire extinguishing agents without the secondary damage caused by residuals after the fire extinguishment like a case of the powder fire extinguishing agent, were developed. And experiments using a vehicle collision after the discharge is complete, foreign material can be removed without extinguishing the advantage that experimental results obtained.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.11
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• pp.259-272
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• 2019

Steel-concrete single-leaf blast-resistant doors are protective structures consisting of a steel box and reinforced concrete slab. By the domestic blast-resistant doors, the structure is not designed efficiently because few studies have examined the effects of variables, such as the blast pressure, rebar ratio, and steel plate thickness on the structural behavior. In this study, the structural behavior of the doors was analyzed using the FE method, and the support rotation and ductility ratio used to classify the structural performance were reviewed. The results showed that the deflection changes more significantly when the plate thickness increases than when the rebar spacing is a variable. This is because the strain energy absorbed by the door is reduced considerably when the plate thickness increases, and as a result, the maximum deflection becomes smaller. According to a comparison of the calculated values of the support rotation and the ductility ratio, the structural performance of the doors could be classified based on the support rotation of one degree and ductility ratio of three. On the other hand, more explosion tests and analytical studies will be needed to classify the damage level.

• Journal of the Korean Institute of Gas
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• v.18 no.3
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• pp.38-43
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• 2014

This paper is to analyze and study the failure examples of fire by inflammables and electric contact faulty in interior of vehicle. The first example, the driver used to air freshener that remove the air conditioner bad smell. He get out of a car. And then, he put it on the crash pad. Before long, a fire breaks out because of explosion solar radiation. The second example, the driver used in room of a car. It certified the fire by disconnection phenomenon happened the electric overload. The third example, the driver install the heat rays to warm his body, In the initial stages, it didn't seek the dangerous of fire during using a car to 5,000km. This heat rays become to down durability so that produced the electric overload in an instant. The fourth example, after the man smoked the cigarette on riding with rear seat, he put it on seat in vehicle no extinguishing the burning cigarette. It knew the fact that burnt to ashes a car by on well combustible paper. Thus, the driver must consider a countermeasure for minimize the fire production when he use the inflammable and install adding electric system.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.3
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• pp.129-136
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• 2020

A Cut Out Switch (COS) is used for line protection and pole transformer protection in power systems. The COS used to protect the pole transformer is installed on the power side of the pole transformer to protect the electric equipment from fault currents. The COS is composed largely of a body and a fuse holder, and when the fault current is energized, the element of the fuse link in the fuse holder is melted to block the fault current. The arc generated when the COS fuse link is blown causes fire and noise, causing discomfort to residents in the surrounding area, and the arc flame can cause secondary damage to the peripheral device. In this study, a current-limiting COS fuse with improved overcurrent blocking performance rather than explosion type was developed to solve the arc and noise problems during COS operation. The overcurrent breaking performance of the current-limiting COS improves the reliability by developing a striker and COS fuse bracket. In addition, this study aimed to verify the performance of the developed current-limiting COS fuse through a test at an authorized institution.

• Journal of Trauma and Injury
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• v.26 no.3
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• pp.111-124
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• 2013

Purpose: We should prepare proper medical service for disaster control as South Korea is not free from terrorism and war, as we experienced through the two naval battles of the Yeonpyeong, one in 1999 and the other in 2002, the sinking of Cheonan in 2010, and the attack against the border island of Yeonpyeong in 2010. Moreover, North Korea's increasingly bellicose rhetoric and mounting military threats against the world demand instant action to address the issue. The aim of this article is to describe our experience with three patients with combat-related gunshot and explosive injuries to their extremities and to establish useful methods for the management of patients with combat-related injuries. Methods: Three personnel who had been injured by gunshot or explosion during either the second naval battle of the Yeonpyeong in 2002 or the attack against the border island of Yeonpyeong in 2010 were included in our retrospective analysis. There were one case of gunshot injury and two cases of explosive injuries to the extremities, and the injured regions were the left hand, the right foot, and the right humerus. In one case, the patient had accompanying abdominal injuries, and his vital signs were unstable. He recovered after early initial management and appropriate emergency surgery. Results: All patients underwent emergent surgical debridement and temporary fixation surgery in the same military hospital immediately after their evacuations from the combat area. After that, continuous administration of antibiotics and wound care were performed, and definite reconstructions were carried out in a delayed manner. In the two cases in which flap operations for soft tissue coverage were required, one operation was performed 5 weeks after the injury, and the other operation was performed 7 weeks after the injury. Definite procedures for osteosynthesis were performed at 3 months in all cases. Complete union and adequate functional recovery were achieved in all cases. Conclusion: The patient should be stabilized and any life-threatening injuries must first be evaluated and treated with damage control surgery. Staged treatment and strict adherence to traditional principles for open fractures are recommended for combat-related gunshot and explosive injuries to the extremities.

• Fire Science and Engineering
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• v.32 no.1
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• pp.89-98
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• 2018

Fire accidents in foreign countries, like the accident in a thermal power plant in Beijing, the accidents in domestic power plants, including Boryeong Power Plant in 2012 and Taean Power Plant in 2016, a disaster in a nuclear power plant in Fukushima in 2011 or the large-scale power failure in California in 2001 are safety accidents related to electric power, which caused losses in the people's stable lives and the countries. Electricity has an absolute impact on the people's life and the economy, so we can easily expect the serious situation affecting economic growth as well as direct damage to the protection of the people's lives and the losses of properties, if there are fire or explosion accidents or radioactive leak because of negligence in safety management, or problems because of natural disasters like an earthquake in power plants that generate electricity. In this study, it was drawn the improvement of the organizations exclusively in charge of firefighting, the operation of a program for the improvement of professional competency, the development of a customized firefighting management system for plants for systematic firefighting safety management and the improvement of the earthquake-proof correspondence system, which has recently become an issue, as measures for improvements through a survey of the actual conditions concerning the necessity of the construction of a firefighting safety management system for power plants with five power generation companies, including Korea Southern Power Co., Ltd., and the persons in charge of firefighting safety Korea Hydro & Nuclear Power Co., Ltd.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.27 no.2
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• pp.71-78
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• 2014

There is a big risk of bullet impact because military rotorcraft is run in the battle environment. Due to the bullet impact, the rapid increase of the internal pressure can cause the internal explosion or fire of fuel cell. It can be a deadly damage on the survivability of crews. Then, fuel cell of military rotorcraft should be designed taking into account the extreme situation. As the design factor of fuel cell, the internal fluid pressure, structural stress and bullet kinetic energy can be considered. The verification test by real object is the best way to obtain these design data. But, it is a big burden due to huge cost and long-term preparation efforts and the failure of verification test can result in serious delay of a entire development plan. Thus, at the early design stage, the various numerical simulations test is needed to reduce the risk of trial-and-error together with prediction of the design data. In the present study, the bullet impact numerical simulation based on SPH(smoothed particle hydrodynamic) is conducted with the commercial package, LS-DYNA. Then, the resulting equivalent stress, internal pressure and bullet's kinetic energy are evaluated in detail to examine the possibility to obtain the configuration design data of the fuel cell.

• Explosives and Blasting
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• v.36 no.4
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• pp.35-47
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• 2018

In this study, several concrete-block blast tests and AUTODYN numerical analyses were conducted to analyze the effects of different stemming and coupling materials on explosion results. Air, sand, and polymer gel were used as both the stemming and coupling materials. The stemming and coupling effects of these materials were compared with those of the full-charge condition. Soil-covered or buried concrete blocks were used for field crater tests. It was found from the concrete block tests and numerical analyses that both the crater size and the peak pressure around the blast hole were higher when the polymer gel was used than when the sand and the decoupling condition were used. The numerical analyses revealed the same trend as those of the field tests. Pressure peaks in concrete block models were calculated to be 37, 30, and 16 MPa, respectively, for the cases of the polymer gel, sand, and no stemming and decoupling condition. The pressure peak was 52 MPa in the case of full-charge condition, which was the highest pressure. But the damage area for the case was smaller than that obtained from the use of polymer gel. Full-charge was also used as a reference test.

• Journal of the Korean earth science society
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• v.42 no.6
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• pp.623-631
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• 2021

The increased transport of marine hazardous and noxious substances (HNS) has resulted in frequent HNS spill accidents domestically and internationally. There are about 6,000 species of HNS internationally, and most of them have toxic properties. When an accidental HNS spill occurs, it can destroys the marine ecosystem and can damage life and property due to explosion and fire. Constructing a spectral library of HNS according to wavelength and developing a detection algorithm would help prepare for accidents. In this study, a ground HNS spill experiment was conducted in France. The toluene spectrum was determined through hyperspectral sensor measurements. HNS present in the hyperspectral images were detected by applying the spectral mixture algorithm. Preprocessing principal component analysis (PCA) removed noise and performed dimensional compression. The endmember spectra of toluene and seawater were extracted through the N-FINDR technique. By calculating the abundance fraction of toluene and seawater based on the spectrum, the detection accuracy of HNS in all pixels was presented as a probability. The probability was compared with radiance images at a wavelength of 418.15 nm to select abundance fractions with maximum detection accuracy. The accuracy exceeded 99% at a ratio of approximately 42%. Response to marine spills of HNS are presently impeded by the restricted access to the site because of high risk of exposure to toxic compounds. The present experimental and detection results could help estimate the area of contamination with HNS based on hyperspectral remote sensing.