• Fire Science and Engineering
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• v.28 no.3
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• pp.29-33
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• 2014

Cleanroom fires were simulated by using Fire Dynamics Simulator. A grid size of $0.5{\times}0.5{\times}0.2m^3$ was selected following review of grid sizes. Fires in three large cleanrooms were investigated to confirm safety by applying the requirements on temperature, visibility, and carbon monoxide concentration in performance based design. The worst situation without sprinkler system and air flow of 0.1 m/s downward in the cleamrooms was considered. It was confirmed that all the three cleanrooms were safe in case without sprinklers since the temperature was below the safety requirement. Decrease in visibility and carbon monoxide concentration due to the fires were negligible.

• Fire Science and Engineering
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• v.26 no.1
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• pp.102-112
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• 2012

In this research, configulation of outside sprinkler system the prevention and postponement of vertical diffusion of blaze was studied prior to this study, vertical diffusion protecting sprinkler head has been developed and the sprinkler system was applied with discharge pressure of 0.05 MPa and flow of 60 l/min witch is stated in NFPA13's Exposure Protection Sprinkler Systems. Through the system design, we applied the system to the sample building and we made pertinent system to work manually and automatically linked to a fire alarm system. Also, we conducted a real-size mock up test verify the cooling effect of the outer wall and the postponement effect of the flame.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.9
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• pp.1316-1322
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• 2000

Data were compiled and statistically analyzed on the lactation of 50% and 75% Thai native-Friesian crossbred and purebred Friesian cows that were fed at a national institute in Chiang Mai, Thailand. More than 30% higher milk production was obtained in the 75% crossbred compared with that in the 50%, but this amount of milk production in the upgraded breed was still about half that of purebred Friesians; 2,138 kg, least squares means during an average lactation period of 279 days in the 50% crossbred, 2,847 kg during 277 days in the 75% crossbred and 5,585 kg during 308 days in the purebred. Environmental stress due to tropical climate was alleviated by the use of electric fans and water sprinklers in the feeding house during the hot season, and improved diet seemed to enable purebred Friesians to keep their ability to produce a milk quantity of more than 6,500 kg per year. This special care was not given to crossbreds and significantly negative correlations were found between daily minimum temperature and humidity during the initial 100 days of lactation and total milk production and average daily milk yield in the 75% crossbreds. However, these correlations were not found in the 50% crossbreds.

• Fire Science and Engineering
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• v.30 no.4
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• pp.14-19
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• 2016

When an interior fire occurs in an apartment building, pollution of the entrance area by fire smoke before an air fan operates makes the evacuation of people very difficult aswhen the fire doors are opened. Numerical simulations using Fire Dynamics Simulator were conducted to determine the impact of a sprinkler on the fire flow velocity. The fire flow velocity was compared depending on the presence of sprinklers and the sprayed droplet size. The configuration and actual dimensions of an apartment building were used in the numerical simulations. The simulation results showed that fire flow velocity becomes smaller when a sprinkler is installed. In addition, the smaller droplet size results in a smaller fire flow velocity because smaller droplets can be evaporated more easily.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.2
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• pp.39-47
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• 2020

The fire protection system for high-rise buildings is currently confined to the preparation of sprinklers, emergency stairs, and exit and monitoring systems. On the other hand, an integrated system, including the model with scenario-based actions, is required for effective fire protection. An integrated fire protection system is needed to operate and manage the total cycle of the fire protection. In this study, an integrated fire protection system, which included sensing and consequent processes related to fire emergencies, was designed and implemented. The designed scheme can gather and analyze the data of the production, operation, and consumption patterns as it integrates fire protection systems for fire fighters and evacuating people. The integrated fire protection technology and system, which has target performance with satisfied 1/2 sec transaction response time and 1.2 transactions per second, is expected to contribute to market creation in converged technology-based fire protection fields.

• Fire Science and Engineering
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• v.30 no.6
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• pp.84-91
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• 2016

In case of fire, vertically and intensively loaded rack warehouses are faced with a severe status due to the rapid increase in fires. In this regard, there have been trials to prevent fires from spreading by applying fire extinguishing systems, such as ESFR and In-Rack Sprinklers, vertical and horizontal barriers, etc.; however, it is difficult to calculate and design proper fire extinguishing systems caused by various composition conditions, such as the size and loading density of the rack, types of loading commodities, etc. Therefore, in this study, a standard rack was manufactured, incorporating a rack warehouse in Korea by site investigations, surveys, etc. In addition, a full scale fire test was executed to check the fire characteristics depending on the conditions of the ignition points. As a result, the extracted fire spread speed is expected to be utilized as a reference for performance comparisons of the fire extinguishing systems to be developed and applied in the future.

• Journal of the Society of Disaster Information
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• v.9 no.4
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• pp.413-422
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• 2013

This study evaluated the fire safety code elements through analyze the loss of life when the fire occurred in the facility sprinklers installed evaluated. And through comparison with national fire safety code elements and standards of NFPA 13 in the United States, Was looking for ways to improve for Life and property damage. In the United States, in some cases, if you do not install the sprinkler are installed as per the fire death rate compared to 83 % lower. By contrast, If the domestic rate of 280 % fatalities were 3.37 times than the United States. This lack of fire performance were analyzed uniform occupancy classification, the amount of source of water supply, live not consider the density according to the standard number and the horizontal distance that causes the installation of sprinkler facilities were analyzed.

• Fire Science and Engineering
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• v.27 no.3
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• pp.14-19
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• 2013

National Fire Safety Code 103 regulates that all operating sprinkler in design area must be discharged 1 bar or more pressure and release 80 lpm or more flow rate as minimum criteria. NFSC103 also provides that the number of operating sprinkler in design area is 10, 20, 30 according to the building classification and the total flow rate is 800, 1,600, 2,400 lpm depending on 80 lpm per sprinkler. If sprinkler system is designed as above provisions, the pressure and the flow rate accordingly become smaller than the minimum criteria about 50 % sprinklers. It results in serious consequence that the purpose of sprinkler system as initial fire reaction equipment is failure. In order to solve these problems, It is desirable that Performance-based fire protection design, hydraulic calculation, is carried out to all sprinkler system.

• Fire Science and Engineering
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• v.24 no.3
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• pp.93-98
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• 2010

Even though the sprinkler system is a essential fire suppression system, the design engineers do not fully understand the concept of design area which sprinklers operate. They frequently made a mistake to form design area and calculate it. The shape of design area is a square or a rectangle which branch side line is a little longer than the cross main side. NFPA demands to lengthen the branch side to 1.2 times than the cross main side and FM demands 1.4 times. The longer the branch side at the same design area is, the bigger the water quantity and pressure is. At the results of hydraulic calculation of design areas, when the branch side is longer 1.2 times, the water quantity became 4.6% bigger than exact square and the pressure came to 4.67% bigger. When it is longer 1.4 times, the water quantity and the pressure are bigger 7.52%, 14.51%. Therefore, the sprinkler design engineers should follow the general rule of design area, exact square or rectangle which length along the branch line is a little longer than length along the cross main, to design more stable system.

• Fire Science and Engineering
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• v.29 no.1
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• pp.73-79
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• 2015

There are three kinds of design method of the fire sprinkler systems. Grid type is connected all branch as a trapezoid. Loop type is connected cross-mains like circle. The last one is a tree type most commonly used. Grid type needs computer program to calculate the friction loss and flow rate apart from very simple form. In loop type, manual calculation is possible. Design engineer can draw up and calculate the demands without computer program. Because water supplies two direction in loop type, friction loss is smaller than tree type. Water distribution in operation area is uniform because of the small differences of sprinklers discharge pressure. Loop type is superior to tree type in respect of total pressure and flow rate. Using the small diameter pipe, the labor and construction cost will be decreased in the end. Loop type sprinkler design is rarely laid out because design engineers don't know the method. This paper is intended to inform that the loop type is better than the tree type in performance and economic point of view. And also this paper intend to use the loop type easily and widely.