• Fire Science and Engineering
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• v.34 no.1
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• pp.11-17
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• 2020

As performance-based design (PBD) has a direct impact on evacuation safety assessments, designing fire scenarios based on real fire tests is essential. To improve the reliability of the PBD for fire safety in multiplexes, information on fire behavior, such as heat release rate (HRR) and fire spread rate, are provided in this study by conducting a standard fabric flammability test. To this end, several chairs were arranged in a pattern that resembled a theater-style seating. The peak HRR and heating value per unit mass for each chair ranged from 415 kW to 988 kW and 15.2 MJ/kg to 23.8 MJ/kg, respectively. The heating values per unit mass of the new and old chairs were 23.6 MJ/kg and 16.7 MJ/kg, respectively. As the quantity of plastic and cushioning materials in the new chairs was more than that of the old ones, the new chairs were more vulnerable to fire hazards. Furthermore, when the chairs were arranged in a line, the fire spread rate was observed to be 0.39-0.42 m/min, regardless of the ignition location. Finally, a fire growth curve showing the peak HRR and fire spread rate was also demonstrated.

• Journal of Energy Engineering
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• v.18 no.4
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• pp.213-220
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• 2009

The experimental characteristics for fry drying method was investigated using low-rank coal with a high moisture content. Final temperature, mixing ratio between coal and kerosene, content of coal or kerosene, total weight of the mixture and mixing methods were varied to find out the optimum conditions by measuring moisture of coal. Evaporation of the coal moisture was not completed below $120^{\circ}C$ of final temperature. The amount of moisture was not significantly different over $130^{\circ}C$. Coal moisture was easily evaporated by increasing coal content, which showed that the moisture evaporation could be significantly enhanced by the remove of evaporated moisture from kerosene rather than by heat transfer to the coal. High total weight of the mixture resulted in lowering moisture content of coal with long evaporation time. On the other hand, low total weight was difficult to reduce the moisture below a certain level, but could reduce evaporation time. Thus, it can concluded that kerosene content should be lowered to the extent maintaining the mobility of the mixture in order to enhance evaporation. It was also observed that evacuation and mixing by using nitrogen could improve drying of coal.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.5
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• pp.516-521
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• 2016

In this study, we investigated the operation of railroad fire fighting vehicles against fires on trains in a long railway tunnel. In recent years, long railway tunnels (more than 10 km in length) have been built and the number of such tunnels, such as the Geumjeong tunnel (20.3 km in length) on the Gyeongbu high speed line, Solan tunnel (16.7 km in length) on the Yeongdong line and Yulhyeon tunnel (50.3 km in length) on the Suseo high speed line which is scheduled to be opened in the second half of 2016, is increasing. Significant damage is to be expected, due to the increased evacuation time and limited accessibility of fire services when the train is stopped by an urgent fire in the tunnel. Special fire fighting vehicles capable of running on rails have been developed and operated in overseas advanced countries. Therefore, a fire-response system using Unimog vehicles, which can run on road and rail, instead of road vehicles, is necessary. The characteristics of the railway tunnel and thermal environmental change caused by a train fire in a tunnel were analyzed in this study. Also, the operational requirements of the railroad fire fighting vehicles were evaluated by taking into account the specifications of the railroad fire fighting vehicles under development.

• Fire Science and Engineering
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• v.33 no.2
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• pp.68-78
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• 2019

In modern society, the paradigm of terrorism is shifting to the form of soft targets focusing on an unspecified number of people, which is different from previous terrorist tendencies, and frequent attacks using chemicals. Therefore, this study analyzed the evacuation environment and characteristics, manual analysis of a terror response manual, and the domestic chemical management status of multi-use facilities, and proposed the following management measures for chemical terror prevention in multi-use facilities. First, a multi-use facility guideline for prompt onsite response is proposed. Second, an improvement plan is suggested through the analysis of the manual for counter terrorism. Third, integrated management is proposed through the selection of chemicals available for terrorism. Through this, it is expected that an additional improvement plan will be prepared for countermeasures against chemical terrorism in multi-use facilities. In the future, it will be necessary to analyze the problems through cases of foreign countries and take customized countermeasures.

• Journal of Korean Tunnelling and Underground Space Association
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• v.24 no.1
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• pp.95-108
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• 2022

The increase in the use time of tunnel users due to the lengthening of the road tunnel may increase the evacuation time in case of fire, resulting in a large number of casualties. In order to reduce the casualties caused by fire, the "Road Tunnel Design Manual, Part 6 Tunnel" and "Road Tunnel Disaster Prevention Facility Installation and Management Guidelines" stipulate that ventilation facilities should be installed along with the extension of the tunnel. The ventilation system design factor considers the wind speed of the external natural wind to be at least 2.5 m/s, and it is applied upward according to the characteristics of the tunnel. As a result of analyzing the five-minute average wind speed data in the Daegwallyeong region for the past 6 years, it was analyzed that 15.8% of the windy days were winds of 10 m/s or more, and the maximum was 20 m/s. Therefore, in this study, when a fire occurs in a tunnel, the pattern of natural wind flowing into the tunnel and the backlayering distance of the tunnel fire smoke according to the maximum wind speed were analyzed. As a result, it was analyzed that a backflow of up to 490 m occurs when a gust of 20 m/s blows.

• Journal of the Society of Disaster Information
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• v.18 no.4
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• pp.806-816
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• 2022

Purpose: In this study, the luminance measurement analysis results of the smoke generation state are considered for visual signal display light color for real-time escape guidance in the underground common area. Method: We will analyze the scattering characteristics of light in the atmosphere and optical technology based on the visibility theory, and try to classify the elemental technology as a guidance function through a prototype of a visual signal display device for evacuation guidance. Result: In the experiment conducted under the smoke-generating condition, the results were derived with low luminance ratio and good visibility in the order of red, green, and yellow. However, this result is different from general lighting in which color rendering is considered, and is limited to signals for signals and detection. Conclusion: A conclusions were drawn by reflecting both the luminance measurement results in the smoke generation situation and the preference survey results conducted in previous studies for the light color of the visual signal for signal and detection. When events such as smoke occur, it is better to use the escape guidance visual signal in red or green.

• Journal of Korea Water Resources Association
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• v.56 no.1
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• pp.53-62
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• 2023

Recently, due to the influence of climate change, the occurrence of damage to heavy rain is increasing around the world, and the frequency of heavy rain with a large amount of rain in a short period of time is also increasing. Heavy rains generate a large amount of outflow in a short time, causing flooding in the downstream part of the mountainous area before joining the small and medium-sized rivers. In order to reduce damage to downstream areas caused by flooding, it is very important to calculate the outflow of mountainous areas due to torrential rains. However, the sewage network flooding analysis, which is currently conducting the most analysis in Korea, uses the time and area method using the existing data rather than calculating the rainfall outflow in the mountainous area, which is difficult to determine that the soil characteristics of the region are accurately applied. Therefore, if the rainfall is analyzed for mountainous areas that can cause flooding in the downstream area in a short period of time due to large outflows, the accuracy of the analysis of flooding characteristics that can occur in the downstream area can be improved and used as data for evacuating residents and calculating the extent of damage. In order to calculate the rainfall outflow in the mountainous area, the rainfall outflow in the mountainous area was calculated using MIKE SHE among the MIKE series, and the flooding analysis in the downstream area was conducted through MIKE 21 FM (Flood model). Through this study, it was possible to confirm the amount of outflow and the time to reach downstream in the event of rainfall in the mountainous area, and the results of this analysis can be used to protect human and material resources through pre-evacuation in the downstream area in the future.

• The Journal of the Korean bone and joint tumor society
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• v.14 no.2
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• pp.163-171
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• 2008

Purpose: We analyze the characteristics of soft tissue sarcomas presented with hematoma, which were misdiagnosed as simple hematoma initially and the proper management were delayed. Materials and Methods: The 7 patients with histologically proven soft tissue sarcoma with hematoma presented since February 1997 were evaluated retrospectively. Neither patient had a medical history of bleeding tendency nor anticoagulant therapy. Two of them had minor traumas. There were 2 men and 5 women. Average follow up period was 58 months. MRI findings, provided treatments and oncologic outcome were reviewed with the reference of related articles. Results: Retrospective review of initial MR images revealed deep seated intramuscular masses with focal solid enhanced nodules at the peripheral margin. The diagnoses were delayed at least 1 month in 3 of them which included 2 cases of simple hematoma evacuation without biopsy initially. After histologic diagnosis of soft tissue sarcoma, wide resections were performed in 4 cases. one patient underwent above knee amputation and the remained 2 patients were managed with wide resection followed by amputation due to local recurrence. At last follow up there were CDF and NED in 2 cases, respectively and AWD in 3 cases. Conclusion: To avoid the delay of diagnosis and treatment of soft tissue sarcomas presented with hematoma, high degree of clinical suspicion, careful analysis of MR images and early biopsy were important.

• Journal of Korean Tunnelling and Underground Space Association
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• v.24 no.4
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• pp.327-339
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• 2022

The purpose of this study is to present the effective smoke control flow rate and mode for securing safety through quantitative risk assessment according to the smoke control flow rate and mode (supply or exhaust) of the platform when a train fire occurs at the subway platform. To this end, a fire outbreak scenario was created using a side platform with a central staircase as a model and fire analysis was performed for each scenario to compare and analyze fire propagation characteristics and ASET, evacuation analysis was performed to predict the number of deaths. In addition, a fire accident rate (F)/number of deaths (N) diagram (F/N diagram) was prepared for each scenario to compare and evaluate the risk according to the smoke control flow rate and mode. In the ASET analysis of harmful factors, carbon monoxide, temperature, and visible distance determined by performance-oriented design methods and standards for firefighting facilities, the effect of visible distance is the largest, In the case where the delay in entering the platform of the fire train was not taken into account, the ASET was analyzed to be about 800 seconds when the air flow rate was 4 × 833 m³/min. The estimated number of deaths varies greatly depending on the location of the vehicle of fire train, In the case of a fire occurring in a vehicle adjacent to the stairs, it is shown that the increase is up to three times that of the vehicle in the lead. In addition, when the smoke control flow rate increases, the number of fatalities decreases, and the reduction rate of the air supply method rather than the exhaust method increases. When the supply flow rate is 4 × 833 m³/min, the expected number of deaths is reduced to 13% compared to the case where ventilation is not performed. As a result of the risk assessment, it is found that the current social risk assessment criteria are satisfied when smoke control is performed, and the number of deaths is the flow rate 4 × 833 m³/min when smoke control is performed at 29.9 people in 10,000 year, It was analyzed that it decreased to 4.36 people.