• Journal of the Computational Structural Engineering Institute of Korea
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• v.29 no.4
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• pp.369-376
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• 2016

In this study, a numerical analysis framework for investigating the nonlinear behavior of structures under fire conditions is presented. In particular, analysis procedure combining fire-driven flow simulation and thermo-mechanical analysis is discussed to investigate the mechanical behavior of fire-exposed representative volume structures made of steel and concrete, respectively. First of all, fire-driven flow analysis is conducted using Fire Dynamics Simulator(FDS) in a rectangular parallelepiped domain containing the structure. The FDS simulation yields the time history of temperature on the surface of the structure under fire conditions. Second, mechanical responses of the fire-exposed structure with respect to prescribed uniformly distributed loads are calculated by a coupled thermo-mechanical analysis using the time-varying surface temperature as boundary conditions. Material nonlinearities of steel and concrete have been considered in the thermo-mechanical analysis. A series of numerical results are presented to demonstrate the feasibility of the multiphysics structural fire analysis for investigating the structural behavior under fire conditions.

• Fire Science and Engineering
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• v.26 no.3
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• pp.21-28
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• 2012

The objective of this study is to evaluate the prediction accuracy of FDS(Fire Dynamic Simulator) for the thermal and chemical characteristics of under-ventilated fire with unsteady fire growth in a semi-closed compartment. To this end, a standard doorway width of the full-scale ISO 9705 room was modified to 0.1 m and the flow rate of heptane fuel was increased linearly with time (until maximum 2.0 MW based on ideal heat release rate) using a spray nozzle located at the center of enclosure. To verify the capability of FDS, the predicted results were compared with a previous experimental data under the identical fire conditions. It was observed that with an appropriate grid system, the numerically predicted temperature and heat flux inside the compartment showed reasonable agreement with the experimental data. On the other hand, there were considerable limitations to predict accurately the unsteady behaviors of CO and $CO_2$ concentration under the condition of continuous fire growth. These results leaded to a discrepancy between the present evaluation of FDS and the previous evaluation conducted for steady-state under-ventilated fires. It was important to note that the prediction of transient CO production characteristics using FDS was approached carefully for the under-ventilated fire in a semi-closed compartment.

• Journal of Digital Convergence
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• v.15 no.9
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• pp.23-33
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• 2017

Given the expansion of globalization and international trade, the number of apparel consumers is growing every year, making it difficult to estimate the amount of handling needed from the logistics industry. To determine which management factors are important and which ones require improvement, fuzzy AHP was used. Using this method, the factors were ranked in the final analysis as follows: The first and most important factor was training employees (0.17), while the second was fire hazard management (0.169); the third-highest factor was inbound and outbound goods (0.142), and the fourth was the warehouse management system. Barcode management was ranked fifth. By these results, we were able to analyze the processes of clothing warehouses, noting that although the factors appear independent, they are actually connected while proceeding with full management control. Moreover, because of the special characteristics of garments, employee management is crucial. Due to the vulnerability of these goods to fire hazards, this factor must be well managed.

• Fire Science and Engineering
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• v.33 no.4
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• pp.1-8
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• 2019

Reaction-to-fire performance of pipe insulation materials should be approved in accordance with KS standards prior to installing water-based suppression systems because several fire accidents are initiated from insulation materials around ceilings or concealed space. A small room test to evaluate the reaction-to-fire performance of the polyethylene foam and elastomeric pipe insulation materials was conducted according to ISO 20632. Different fire growth rate and heat release rate are observed depending on the materials and construction methods. In order to improve a fire safety, the reaction-to-fire performance of pipe insulation material needs to be subdivided with regard to the heat release rate and smoke generation. Furthermore, the characteristics of the applying space are also required to be considered. Subsidiary materials for installation process such as tape and adhesive are found to provide an adverse effect to maintain a fire safety.

• Fire Science and Engineering
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• v.34 no.4
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• pp.22-28
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• 2020

The heat release rate (HRR) of fire for solid combustibles, consisting of multi-materials, was measured using the ISO 9705 room corner test, and a computational analysis was conducted to simulate the fire using an HRR prediction model that was provided by a fire dynamics simulator (FDS). As the solid combustible consisted of multi-materials, a cinema chair composed primarily of PU foam, PP, and steel was employed. The method for predicting the HRR provided by the FDS can be categorized into a simple model and a pyrolysis model. Because each model was applied and computational analysis was conducted under the same conditions, the HRR and fire growth rate predicted by the pyrolysis model had good agreement with the results obtained using the ISO 9705 room corner test.

• Fire Science and Engineering
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• v.32 no.5
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• pp.6-14
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• 2018

This study was carried out with respect to the heat release rate (HRR) properties of building wood. Heat release characteristics were measured using a cone calorimeter (ISO 5660-1) with four kinds of wood. The time to ignition measured after the combustion in $25kW/m^2$ external heat flux was 35 to 55 s. Time to ignition of both lauan and red pine was marked with the most delayed value in each of 54 s, 55 s. The maximum heat release rate ($HRR_{peak}$) was $156.87{\sim}235.1kW/m^2$, and the risk of early fire was highest in spruce. Total heat release of red pine was obtained in the highest value with $114.2MJ/m^2$. The mean effective heat of combustion of Japanese cedar was 19.1 MJ/kg and the highest among the samples. Fire risk of wood by FPI was orderly increased from lauan ($0.2468s{\cdot}m^2/kW$), red pine ($0.2339s{\cdot}m^2/kW$), spruce ($0.2308s{\cdot}m^2/kW$) to Japanese cedar ($0.2231s{\cdot}m^2/kW$). Fire risk of wood by FGI get increased from lauan ($0.5088kW/m^2{\cdot}s$), red pine ($0.5111kW/m^2{\cdot}s$), Japanese cedar ($2.8522kW/m^2{\cdot}s$) to spruce ($3.0662kW/m^2{\cdot}s$). Therefore, the risk of fire on the heat release characteristics of woods were found that spruce and Japanese cedar showed the high value compared with the other specimens.

• Asia Marketing Journal
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• v.10 no.3
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• pp.103-125
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• 2008

After having changed its corporate brand from LG Fire & Marine Insurance to LIG Non-life Insurance in 2006, LIG Insurance has successfully built the corporate image as the leading insurance financial group by engaging in extensive corporate social responsibility activities. LIG, as 'a partner for sharing precious moments of life', intended to provide customers a new value of an insurance by building up the new corporate brand. It established three values to be shared internally. First was to instill a brand value orientation within the organization. Second, the firm identified the brand's value to be delivered to the customers. Third, they defined the image objective to be communicated to them. Based on these set of objectives, the company designed and implemented an integrated marketing communication(IMC) strategy over several years. The result was a successful transition to the new corporate brand name.

• Journal of the Korean Society of Safety
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• v.30 no.3
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• pp.45-51
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• 2015

This study was full-scale combustion test for flame growth characteristics and temperature characteristics analysis to predict the risk of household Items fire when fire occurs. Experimental results, Refrigerator flames were the highest measured in 15 min time, and Washing machine is between 20 ~ 30 min, Drawer is 5 min, Sofa was enabled up to the size of the flame 15 min. In addition, the maximum combustion temperature was found from the time 20 min ~ 25 min, Sofa is temperature was elevated up to $1190^{\circ}C$, Refrigerator is $1,162^{\circ}C$, Drawer is $822^{\circ}C$, Washing machine appeared to be rising up to $670^{\circ}C$. Therefore, in the case of the maximum temperature of combustion Sofa it showed relatively high.

• Fire Science and Engineering
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• v.31 no.4
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• pp.95-102
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• 2017

The fires in the traditional markets often occur recently with the most of them expanded into great fires so that the damage is very serious. The status of traditional markets handling the distribution for ordinary people is greatly shrunk with the aggressive marketing of the local large companies and the foreign large distribution companies after the overall opening of the local distribution market. Most of the traditional markets have the history and tradition from decades to centuries and have grown steadily with the joys and sorrows of ordinary people and the development of the local economy. The fire developing to the large fire has the characteristics of the problem that the fire possibility is high since all products can be flammable due to the deterioration of facilities, the arbitrary modification of equipment, and the crowding of the goods for sale. Furthermore, most of the stores are petty with their small sizes so that the passage is narrow affecting the passage of pedestrians. Accordingly, the traditional markets are vulnerable to fire due to the initial unplanned structural problem so that the large scale fire damage occurs. The study is concerned with systematically classifying and analyzing the result by applying the TRIZ tool to the fire risk factors to extract the fundamental problem with the fire of the traditional market and make the active response. The study was done for preventing the fire on the basis of it and the expansion to the large fire in case of fire to prepare the specific measure to minimize the fire damage. On the basis of the fire expansion risk factor of the derived traditional market, the study presented the passive measures such as the improvement of the fire resisting capacity, the fire safety island, etc. and the active and institutional measures such as the obligation of the fire breaking news facilities, the application of the extra-high pressure pump system, the divided use of the electric line, etc.

• Journal of Korean Tunnelling and Underground Space Association
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• v.15 no.3
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• pp.289-300
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• 2013

This study numerically considered the characteristic of smoke movement and the effect of hot smoke gas on tunnel wall surface temperature during road tunnel fire under boundary condition of fire growth curve that is applied to fire analysis in road tunnels. The maximum heat release rate were 20 MW and 100 MW and tunnel air velocities were 2.5 m/s and velocity induced by thermal buoyancy respectively, also the cooling effect of tunnel wall was considered. As results, when tunnel air velocity was constant at 2.5 m/s during tunnel fire, due to the cooling effect of tunnel wall, the smoke layer was rapidly descent after some distance and it flowed the same patterns at the downstream. When heat release rate was 100 MW (and jet fan was not installed), the maximum temperature of tunnel wall surface has risen up to $615^{\circ}C$. The heat transfer coefficient of tunnel wall surface was varied from 13 to $23W/m^2^{\circ}C$ approximately.