• Journal of the Korean Association of Geographic Information Studies
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• v.1 no.2
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• pp.1-13
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• 1998

The objective of this paper is to develop a cartographic model for water tank suitability for small forest fire extinction using GIS. Various digital maps were created using CAD & GIS for Amnam urban park, which is located in Seogu, Pusan city. The park had 4 small water tanks for fire extinction. The developed descriptive cartographic model identified the spatial effects of fire extinction due to the existing facilities. The prescriptive model to enhance spatial effects was developed for the determination and comparison of the effects of forest fire extinction due to the proposed facilities. This paper proved the techniques of GIS and cartographic modelling are significant for the suitability analysis of water tanks for small forest fire extinction.

• Structural Engineering and Mechanics
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• v.80 no.6
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• pp.701-709
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• 2021

The paper aims at improving the understanding and mitigating the effects of tunnel fires that may breakout due to the burning fuel and/or explosion within the tunnel. This study particularly focuses on the behavior of the commonly used horse shoe geometry of tunnel systems. The problem has been obtained using an adequate well-established program incorporating the Lagrangian approach. A transient-thermo-coupled static structural analysis is carried out. The effects of radiation and convection to the outer walls of the tunnel is studied. The paper also presents the impact of the hazard on the structural integrity of the tunnel. A methodology is proposed to study the tunnel fire using a model which uses equivalent steel sheet to represent the presence of reinforcements to improve the computational efficiency with adequate validation. A parametric study has been carried out and the effect of suitable lining property for mitigating the fire hazard is arrived at. Detailed analysis is done for the threshold limits of the properties of the lining material to check if it is acceptable in all aspects for the integrity of the tunnel. The study may prove useful for developing insights for ensuring tunnel fire safety. To conduct such studies experimentally are tremendously costly but are required to gain confidence. But, scaled models, as well as loading and testing conditions, cannot be studied by many trials experimentally as the cost will shoot up sharply. In this context, the results obtained from such computational studies with a feasible variation of various combinations of parameters may act as a set of guidelines to freeze the adequate combination of various parameters to conduct one or two costly experiments for confidence building.

• Steel and Composite Structures
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• v.15 no.1
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• pp.81-101
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• 2013

In this paper a robust 2-noded connection element has been developed for modelling the bolted end-plate connection between steel beam and column at elevated temperatures. The numerical procedure described is based on the model proposed by Huang (2011), incorporating additional developments to more precisely determinate the tension, compression and bending moment capacities of end-plate connection in fire. The proper failure criteria are proposed to calculate the tension capacity for each individual bolt row. In this new model the connection failure due to bending, axial tension, compression and shear are considered. The influence of the axial force of the connected beam on the connection is also taken into account. This new model has the advantages of both the simple and component-based models. In order to validate the model a total of 22 tests are used. It is evident that this new connection model has ability to accurately predict the behaviour of the end-plate connection at elevated temperatures, and can be used to represent the end-plate connections in supporting performance-based fire resistance design of steel-framed composite buildings.

• Tunnel and Underground Space
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• v.8 no.2
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• pp.107-117
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• 1998

In the case of a fire disaster in a uni-directional road tunnel, it is important to determine the critical ventilation velocity to prevent the backflow travelling toward the tunnel exit where vehicles are stopped. The critical ventilation velocity is horizontal velocity to prevent hot smoke from moving toward the tunnel exit. According to Froude modelling, the model tunnel whcih was 300mm in diameter and 21 m in length was made of acryl tubes. Inner section of acryl tubes was clothed with polycarbonate. 1/20 scaled model vehicles were installed to simulate the situation that vehicles are stopped in the tunnel exit. Methanol in a pool type burner was burned in the middle of tunnel to simulate a fire hazard. In this study, the basis of determining the critical ventilation velocity is the ventilation flow rate that is able to maintain the allowable CO concentration in the tunnel section. We assumed that the allowable CO concentration was backflow dispersion index. Futhermore, We intended to find out CO distribution and temperature distribution according as we changed ventilation velocity. The results of this study were that no backflow happened when ventilation velocity was 0.52 m/s in the case of 5.75 kW. If we adapt these results of a fire disaster releasing 10MW heat capacity in real tunnel which is 400m in length, no backflow happens when ventilation velocity is 2.31m/s. After we figured out dimensionless heat release rate and dimensionless ventilation velocity of model test and those of real test to verify experimental correctness, we tried to find out correlation between experimental results of model tunnel and those of real tunnel.

• Spatial Information Research
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• v.14 no.1 s.36
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• pp.151-161
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• 2006

This paper has a goal to construct monitoring web GIS system which displays maps that are results of the fire detecting algorithms using MODIS image. To design and build more efficient system, foreign fire monitoring systems using satellite image are researched and analyzed. As a result of that, the information about interfaces and services provided by them are obtained. In concretely, new logical DFD is used to do a process modelling. ArcIMS 4.0 of ESRI, IIS 5.1 of Microsoft are utilized to build the web GIS System. In the aspects of data input and transfer, a specific module, which converts a binary image to a kind of vector file, is developed to adjust raster data to the web GIS system.

• Fire Science and Engineering
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• v.24 no.3
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• pp.106-112
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• 2010

This study carried out the motion analysis of auto closing systems as basis study for development of auto closing systems for door in smoke control zone. This study established process of auto closing systems and analysis theory based on kinematics mechanism thesis and mechanism modelling of auto closing control units. And this study established engineering data construction and a source technology that can design each element of auto closing control units that choose closing force units through motion analysis simulation based on analysis theory. Therefore, it can give flexibility and elasticity of auto closing units development from this study. Also, it sees that can ready control means and technological countermeasure of smoke by development of auto closing units and secure high reliancity and stability of smoke control systems.

• Fire Science and Engineering
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• v.30 no.5
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• pp.74-81
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• 2016

This study evaluated the habitability of operators for main control room fires in nuclear power plants. Fire modeling (FDS v.6.0) was utilized for a fire safety assessment so that it could determine the performance of the smoke ventilation and operator habitability with the main control room. For this study, it categorized fire scenarios into three cases depending on the conditions in the HVAC system. As a result of fire modelling, it showed that Case 1 (with HVAC) would give rise to the worst situation associated with the absolute temperature, radiative heat flux, optical density, and smoke layer height as deliberating the habitability and smoke ventilation. On the other hand, it showed that Cases 2 (w/o HVAC) and 3 can maintain much safer situations than Case 1. In the case of temperature at 820 s, Cases 2 and 3 were up to approximately 63% greater than Case 1 in the wake of ignition. In addition, the influence of radiative heat flux of Case 1 was even larger than Cases 2 and 3. That is, the radiative heat fluxes of Cases 2 and 3 were approximately 68% higher than Case 1. Furthermore, when it comes to considering the optical density, Case 1 was approximately 93% greater than Cases 2 and 3. Accordingly, it expected that the HVAC system can influence a the performance on the smoke ventilation that can be sustainable for operator habitability. On the other hand, it revealed an inconsecutive pattern for the smoke layer height of Cases 2 and 3 because supply vents and exhaust vents were installed within the same surface.

• Structural Monitoring and Maintenance
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• v.5 no.3
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• pp.363-377
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• 2018

The proper functioning of critical points on transport infrastructure is decisive for the entire network. Tunnels and bridges certainly belong to the critical points of the surface transport network, both road and rail. Risk management should be a holistic and dynamic process throughout the entire life cycle. However, the level of risk is usually determined only during the design stage mainly due to the fact that it is a time-consuming and costly process. This paper presents a simplified quantitative risk analysis method that can be used any time during the decades of a tunnel's lifetime and can estimate the changing risks on a continuous basis and thus uncover hidden safety threats. The presented method is a decision support system for tunnel managers designed to preserve or even increase tunnel safety. The CAPITA method is a deterministic scenario-oriented risk analysis approach for assessment of mortality risks in road tunnels in case of the most dangerous situation - a fire. It is implemented through an advanced risk analysis CAPITA SW. Both, the method as well as the resulting software were developed by the authors' team. Unlike existing analyzes requiring specialized microsimulation tools for traffic flow, smoke propagation and evacuation modeling, the CAPITA contains comprehensive database with the results of thousands of simulations performed in advance for various combinations of variables. This approach significantly simplifies the overall complexity and thus enhances the usability of the resulting risk analysis. Additionally, it provides the decision makers with holistic view by providing not only on the expected risk but also on the risk's sensitivity to different variables. This allows the tunnel manager or another decision maker to estimate the primary change of risk whenever traffic conditions in the tunnel change and to see the dependencies to particular input variables.

• Journal of the Korea Convergence Society
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• v.6 no.6
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• pp.241-246
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• 2015

In cold winter season, the apparatuses of heating and heater which warm up the interior of a room are necessary element and the used amount of these apparatuses from the year 2000 has been increased abruptly. But, the fire accident and the danger of fire are also increased. Therefore, 3D modelling is done by referring three kinds of the electric heaters as the heaters of ceramic, carbon and near infrared ray sold in the city for the design of more safe heating apparatuses in this study. The thermal analyses with these models are carried out and the durabilities due to the thermal deformation and stress are studied. By the background of the study results derived in this study ultimately, the durabilities of electric heater models due to each shape can be anticipated and contributed to the development of new heating apparatus with more safe resistance to fire. And it is possible to be grafted onto the convergence technique at design and show the esthetic sense.

• Fire Science and Engineering
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• v.13 no.3
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• pp.35-42
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• 1999

A occupant load density of contemporary office buildings were surveyed by a building w walk through procedure in Korea. The survey results of ten office buildings are range from 1 2 2 2 213.14 m !person 041.4 ft !person) to 22.69 m /person (244.34 ft !person) with 95% confidence l level and the mean occupant load density is 17.92 m2/person 092.87 ft2/야rson). The impacts of occupant load on evacuation flow time was analyzed by applying time-based egress m model, SIMULEX with various occupant load densities from previous studies. I In order to demonstrate the validation of egress modeling method, fire evacuation exercise a and computer simulation were used to simulate the actual evacuation plan for a high-rise office building. An analysis and comparison of the results of these approaches was made to i illustrate the influence of model limitations on the result of prediction The result of the study shows that the introduction of occupant load concept in building c code of Korea is essential to achieving resonable building life safety design in future.