• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.18 no.2
• /
• pp.186-191
• /
• 2006

In this study, five experiments were carried out, with an orifice located downstream of a fan in case I where upstream duct length is 6 D, and that in the downstream is 4 D and different downstream distance to the fan in the rest, so as to determine the optimal location of the orifice and reduce the duct length of airflow measurement device. The resulting flow rate-pressure drop correlations were found to satisfy the limitation of SMACNA standard, which specified an error of $\pm7.5\%$ based on the real flow rate. Also, the best one of five. cases was achieved with the orifice located midway of the orifice duct four times its diameter long.

• Journal of IKEEE
• /
• v.11 no.4
• /
• pp.137-144
• /
• 2007

Fire Control System(FCS) errors can be classified as hardware errors and software errors, and one of the software errors is from target tracking filter which estimates target's location, velocity, acceleration, and so on. It affects function of ballistic calculation equipment significantly. For gun to form predicted hitting point accurately and enhance hitting rate, we need status information of target's future location. Target tracking filter algorithms consist of Single Singer Model, Fixed Gain filter algorithm, IMM, PBIMM and so on. This paper will design IMM tracking filer, which is going to be! applied to domestic warship. Target tracking filter using CV model, Song model and CRT model for IMM tracking filter is made, and tracking ability is analyzed through Monte-Carlo simulation.

• Fire Science and Engineering
• /
• v.33 no.1
• /
• pp.39-44
• /
• 2019

In this study, the relationships between the material properties of the wall and the fuel mass flux in compartment fire. The fire resistant board (fire-board) and steel plate compartments are constructed with a 0.3 m width, 0.5 m height and 3.0 m length. To obtain the mass loss rate considering the location of the fire origin in compartment, experiments of a heptane pool fire are performed with a combustion area of $0.01m^2$ and $0.0225m^2$. The results show that the initial mass flux of heptane, $0.0087kg/m^2{\cdot}s$, is increased to $0.166kg/m^2{\cdot}s$ for fire board and $0.019kg/m^2{\cdot}s$ for steel plate. It means that the fire-scenario should be considered with the thermal characteristics of the material properties and geometric shapes of the compartment to predict fire propagation accurately in a compartment space.

• Journal of Korean Society for Atmospheric Environment
• /
• v.20 no.4
• /
• pp.437-450
• /
• 2004

Extensive forest fire activities occurred across the border in Russia, particularly east of Lake Baikal between the Amur and Lena rivers in May 2003. These forest fires released large amounts of particulates and gases into the atmosphere, resulting in adverse effects on regional air quality and the global radiation budget. Smoke pollution from the Russian fires near Lake Baikal was transported to Korea through Mongolia and eastern China. On 20 May 2003, a number of large fires were burning in eastern Russian, producing a thick, widespread pall of smoke over much of Northeast Asia. In this study, separation technique was used for aerosol retrieval application with imagery from MODIS aboard TERRA satellites. MODIS true-color image shows the location of fires and the grayish color of the smoke plumes over Northeast Asia. Aerosol optical thckness (AOT) retrieved from the MODIS data were compared with fire hot spots, ground-based radiation data and TOMS -based aerosol index data. Large AOT, 2.0-5.0 was observed on 20 May 2003 over Korea due to the influence of the long range transport of smoke aerosol plume from the Russian fires, while surface observed fine mode of aerosol size distribution increased.

• Journal of the Architectural Institute of Korea Structure & Construction
• /
• v.35 no.11
• /
• pp.137-146
• /
• 2019

Recently, the Near-Surface-Mounting method using Fiber reinforced polymer (FRP) has been developed and applied to the reinforcement of many concrete structural members. However, as a part of the fire resistance design, there is a lack of research related to fire insulation for the areas reinforced with FRP. In case of NSM reinforcement, there is a difference in the transferred temperature from the external surface to the groove corresponding to the location of the groove where the FRP is embedded, and the effect of this should be reflected in the fireproof insulation design. Therefore, in this study, after forming grooves for surface embedding in concrete blocks, fireproof insulation reinforcement was performed using Calcium Silicate (CS) fireproof board and an experiment to evaluate the temperature transfer was performed. By observing the temperature at these groove positions, the reduction of temperature transfer according to fireproof insulation detail was studied. As a result, when the NSM-FRP is properly fire-insulated using the CS-based fireproof board, the epoxy inside the groove does not reach its glass transition temperature until the external temperature reaches $800^{\circ}C$.

• The Journal of the Convergence on Culture Technology
• /
• v.9 no.4
• /
• pp.617-623
• /
• 2023

Among the fire incidents in Korea over the past decade, building fires are the most common, and property and human casualties are the most common. However, the existing fire fighting system does not only inform the location of emergency exits and guide safe routes to help casualties evacuate smoothly. A system was proposed to help successful evacuation by distinguishing vertical and horizontal characteristics using spatial characteristics. In this study, an effective evacuation system was proposed by predicting fires using temperature detection sensors and smoke sensor values, and calculating the optimal evacuation path through the Dijkstra algorithm.

• Fire Science and Engineering
• /
• v.29 no.5
• /
• pp.14-22
• /
• 2015

This thesis is based on the study of necessity of an addressable emergency broadcasting system to improve evacuation performance in order to minimize human casualty by avoiding the initial evacuation after fires such as the multi-unit dwelling fire in Euijeongbu in 2015. To minimize the damage from fire generated in a complex internal structure such as modern buildings, introduction of adaptable emergency broadcasting system, could increase the efficiency of evacuation by preventing of initial mistaken evacuation directions by alerting the accurate location of fire to the occupants, is needed. As such, this study designed and fabricated the addressable emergency broadcasting system using the existing addressable system. Its performance was compared with a conventional emergency broadcasting system to confirm the necessity of the addressable emergency broadcasting system to improve evacuation performance. The test result showed that the addressable emergency broadcasting system decreased the evacuation time by up to 30.3% in a small-scale model evacuation performance experiment, up to 54.6% in a hallway evacuation performance experiment compared to the conventional emergency broadcasting system.

• Fire Science and Engineering
• /
• v.29 no.5
• /
• pp.79-87
• /
• 2015

The placement of Korean fire-fighting administrative power in urban areas shows regional unbalance. In an ideal system, all citizens would be provided with equal fire protection and rescue services, but this is usually difficult to realize due to regional conditions or budget problems. In the case of Busan Metropolitan City, we deduced that it is impossible for half of the buildings to receive rescue services within 5 min, and the conditions are much worse for areas with long or wide fire-fighting service regions. The approach vulnerability for the existing emergency rescue squad locations was assessed. The results revealed that if a rescue team's location is shifted, the improvement effect will be virtually insignificant because of their geographical position. Therefore, this study suggests the establishment of additional rescue squads. It is proven that adding 5 rescue centers in the following locations could solve the problem of approach vulnerability: Bukbu, Gangseo, Geumjeong, Gijang, and Haeundae, in order of effectiveness. The number of buildings in the areas is 53,546.

• Fire Science and Engineering
• /
• v.24 no.6
• /
• pp.28-33
• /
• 2010

The present study develops a numerical model based on the computational fluid dynamics technique to analyse the thermal flow characteristics of large scale fire calorimeter and examine the characteristics of primary parameters affecting on the uncertainty of heat release rate measurement. ANSYS CFX version 12.1 which is a commercial CFD package is used to solve the governing equations of the thermal flow field and the eddy dissipation combustion model and P-1 radiation model are applied to simulate the fire driven flow. The numerical results shows that the horizontal duct system with $90^{\circ}$ bend duct was shown relatively high deviated asymmetric flow profiles at the sampling location and the deviation of the velocity field was higher than that of the temperature and species quantities. The present study shows that the computational model can be applicable to optimize the design process and operating condition of the large scale fire calorimeter based on the understanding of the detail flow field.

• Fire Science and Engineering
• /
• v.23 no.4
• /
• pp.13-18
• /
• 2009

The main objective of the present study is to investigate smoke propagation in railway tunnels with rescue stations. In particular, based on measurement of HRR (heat release rate) for pool fires formed at different locations, the influence of fire source location on smoke behavior is examined. The fuel is n-heptane and pool fires are generated with a square length 4cm. With the use of MVHS (Modified Volumetric Heat Source) model for fire source, extensive numerical simulations are performed by using the commercial code FLUENT (Ver.6.3) Predicted smoke temperatures and smoke propagation are discussed. From numerical predictions, it is found that ventilation systems may be necessary in the railway tunnels because the smoke moves along the tunnel, and consequently it enters the non-accident tunnel. It is also confirmed that the cross-passage and fire protection wall systems contribute to control the smoke.