• 보존과학연구
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• s.31
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• pp.155-171
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• 2010

Wooden cultural heritages have many factors of fires and structural characteristics vulnerable to the fire extinguishing. Also, they are surrounded with forests and so remote from fire stations, which make it difficult to handle it quickly when fires break out. Wooden cultural heritages made of wood materials belong to the general fire in a Class A. Taking characteristics such as a smoldering and a backfire from the that fire of wooden materials into consideration, extinguishing the fire by the cooling system is the most effective. If the fire can't be put out at the early stage, it is almost impossible to protect wooden cultural heritages from the fire, because wooden structures can be destroyed in a high temperature and in a short time and it takes around average 7 minutes to reach its peak of flames in the process of a fire. According to the geographical and environmental situation of the cultural heritages, currently, the fire-prevention facilities such as the auto fire detector for the prompt detection, the water mist fire suppression system for the 1st early and urgent fire suppression and the outdoor fire hydrant and the water curtain etc. for the 2nd full-scale suppression and the prevention of the fire gaining force are being installed for the wooden cultural heritages.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1146_1147
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• 2009

This experiment is significant because we can provide information by measuring effect of energy saving for whom plan to install a geothermal heat & cooling system. The result shows geothemal system can save about 50% of energy(heating : 35%, cooling : 60%) and we verified that when using curtain can help saving 4~12% of energy additionally.

• Fire Science and Engineering
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• v.20 no.4 s.64
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• pp.1-12
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• 2006

In this study, CFD computer simulations by FDS are carried out in order to confirm the performance of the combined operation of both sprinkler system and smoke curtain of 0.54 m depth installed for cooling and blocking the smoke which propagates beneath the sloped ceiling of a stairway corridor of which dimensions are 17.92 m long, 4.00 m wide, and 6.12 m high. It is shown that the response time of sprinklers decreases with fire size and it increases more about 1.1 second in case without smoke curtain than in case with smoke curtain, that the time of smoke transport from the fire source to the stairway outlet decreases considerably with fire size, and that the delay effect of smoke transport is not related to the sprinkler system, whether it is operated or not. This study shows that the combined operation of both sprinkler system and smoke curtain is very effective in smoke cooling, but it is a little for effect on smoke blockage. Although the hazard of skin burn due to radiative heat flux from hot smoke layer is decreased by spray cooling effect, the hazard of smoke suffocation and the weakening of visibility is increased by smoke downdrag and the turbulence of smoke-air mixing due to water spray. These conditions may result in preventing occupants from going out of the stairway during evacuation.

• The Journal of Engineering Geology
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• v.9 no.1
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• pp.17-29
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• 1999

There are three major processes to impact the groundwater flow near underground storage caverns in the coastal area; effect of topography, effect of sea water intrusion, and effect of excavation. In this paper, the effects of three items were numerically studied to identify the major cause for altering the flow pattern. It turned out that the excavation is the most significant effect on the groundwater flow system. The groundwater pressure distributions and consequent groundwater pathways were significantly altered near the openings. By increasing the groundwater pressures from water curtain holes, the potential leakage of storage cavern was properly prevented

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.23 no.2
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• pp.171-181
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• 2011

Recently, many studies have been attempted to save the cost of production and to build the ocean energy power generating system. The low-reflection structure with the wall-typed curtain which has a wave power generation system of OWC is known as the most effective energy conversion system. A three-dimensional numerical model was used to understand the characteristics of velocity of flows about compressed air and to estimate the pressure acting on the low-reflection structure due to the short-period waves. The three-dimensional numerical wave flume which is the model for the immiscible two-phase flow was applied in interpretation for this. The numerical simulation showed well about the changes in velocity of compressed air and the characteristics of pressure according to the change in the wave height and depth of the curtain wall. Additionally, the results found that there was the point of the maximum velocity of the compressed air when the reflection coefficient is at its lowest point.

• Korean Chemical Engineering Research
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• v.60 no.4
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• pp.512-518
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• 2022

In this study, safety devices for ammonia tanks of a company in Ulsan petrochemical industrial complex were studied. The type of a tank is cylindrical and this tank was originally designed to store propylene in 1972. Due to the changes of the production schedule according to market environments, the usage of this tank has been changed to store ammonia. Despite of the changes of materials, there is no scientific information or reviews for guaranteeing the safety. Therefore, in this study, the current status of this tank is investigated to confirm that the operational conditions are complying with safety conditions. Moreover, the safety devices such as an ammonia absorbing system and water curtains are analyzed how they mitigate the impact of an accident. In addition, consequence analysis is performed to provide a proper emergency response plan. Throughout these analysis, it is confirmed that installed safety devices effectively mitigate the impact of accidents, and the necessary time for an emergency response plan is suggested when ammonia release.

• Journal of Bio-Environment Control
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• v.1 no.1
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• pp.61-71
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• 1992

This study is performed to develop an automatic irrigation control of system for effective water management in greenhouse. The automatic irrigation control system is composed of an IR-RED optical sensor in tensiometer and an One-chip micro controller. The following results are obtained : 1. A practical IR-RED optical sensor in tensiometer, which shows the starting point of irrigation, was developed. 2. The automatic irrigation system with the optical sensor and One-chip micro controller was developed and also designed to be able to combine with the control system for temperature, curtain opening, etc. 3. A multiple irrigation control system for several greenhouses were suggested. 4. The results of the system test with the driving program for automatic water management were excellent.

• Fire Science and Engineering
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• v.13 no.4
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• pp.13-19
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• 1999

Currently, conventional fire prevention facility installation standard is based on the use and size of the domestic theaters. In the study, theaters with 1,900 seats were examined to suggest a suitable method to adapt a better fire preventing system. The proposed systems are as follow. - 100% of backup pressed-water outlet device, considering waterproof pressure for fire prevention facility at the top floor. - The supplement of the side wall type header and a large caliber outlet header for stage open sprinkler. - Subdividing a installation rule for special detector and implementing the latestdetector. - Installation of fire curtain for dividing stage area and auditorium area, and also the method of installation of fire curtain.

• Journal of Korea Water Resources Association
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• v.31 no.5
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• pp.553-564
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• 1998

For the proper design and management of underground storage cavern, groundwater flow around cavern should be analyzed. Since this flow is influenced by spatial nonuniformity of hudraulic conductivity, the two-dimensional finite element flow model incorporating stochastic concepts was developed to analyze influences due to this nonuniformity. Monte Carlo technique was applied to obtain an approximate solution for two-dimensional, steady flow in a stochastically defined nonuniform medisu. For this purpose, the values of hydraulic conductivity were generated for each element with known mean and standard deviations. The uncertainty in model prediction depends on both the nonuniformity in hydraulic conductivity and the natures of the flow system such as water curtain and boundary condition. Therefore the uncertainties in predicted hydraulic head and gradient are the greatest where the mean hydraulic gradients are relatively large and far from the boundaries. Especially, we relate these uncertainties with well known gas tightness condition.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2003.04a
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• pp.44-47
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• 2003

시설재배에서 가장 시급한 과제를 꼽는다면 난방에너지 비용의 절감 대책을 들 수 있다. 시설원예농가의 경영비의 30% 이상을 차지하는 난방에너지 비용이야말로 시설원예농가의 경쟁력을 떨어뜨리고, 시설농업의 발전을 가로막는 주원인이라고 할 수 있다. 더욱이 최근의 이라크 전쟁과 화석연료자원의 고갈 예고 등 세계적인 경향 또한 우리나라 시설원예 산업의 발전에 부정적인 영향을 미치고 있는 실정이다. (중략)