• Fire Science and Engineering
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• v.28 no.2
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• pp.20-25
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• 2014

In this study, the extinguishing performance evaluation of wetting agent for wood crib was conducted by using a scale model equipment that we designed. To confirm the optimal conditions of the experiment, a test was changed amount of fire extinguishing water and the number of timber. As a result, the discrimination of the fire extinguishing performance was seen only when 20 pieces of wood and the extinguishing water of 100 mL were used. After evaluating the extinguishing performance of domestic and foreign wetting extinguishing agents under these conditions, a reignition was occurred in only when we used water. In addition, the discrimination of extinguishing performance was seen through the temperature distribution according to the time of watering. Based on the results of this experiment, this study is expected to be able to use as a basis on presenting a method of optimized performance evaluation of wetting extinguishing agent.

• The Journal of the Convergence on Culture Technology
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• v.5 no.3
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• pp.351-357
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• 2019

This research is automatic Wet Pipe Sprinkler System, dry pipe Sprinkler System, preaction Sprinkler system, vacuum Sprinkler system, deluge Sprinkler system, etc., key components of each Sprinkler system, verve valve, valve, etc. This is to simplify the various processes of the manufacturing process into a single process to create an environment in which a single machine can simultaneously produce a standardized product, thereby improving the price competitiveness of the product, reducing the cost of maintaining the product, and making it more adaptable to the new sprinkler system that is developed in the future. Automatic Wet Pipe Sprinkler System, desipe Sprinkler System, preaction sprinkler system, vacuum Sprinkler system, deluge Sprinkler system, both types of existing Sprinkler system, only replace the primary and secondary tubing valves.It has the advantage of being easy to apply to the lower system. Legal and institutional research is needed for the commercialization of the Sprinkler system applying the solenoid valve as a future project.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.12
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• pp.3748-3754
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• 2009

An integral head loss test in a test apparatus was conducted to simulate chemical effects on a head loss across a strainer in a pressurized water reactor (PWR) containment water pool after a loss of coolant accident (LOCA). The test was conducted during 30 days in the condition of a short spray, a long spray, and no materials with chemical effects. The result exhibited that the head loss was affected on amounts of the exposed materials according to spray conditions. XRD analysis of the collected precipitates showed that the precipitates were phosphate compounds. Comparison of the head loss with dissolved species concentration showed that high increase rate of the head loss resulted from the corrosion of aluminum and zinc but slow increase rate of the head loss resulted from the precipitates induced by Si, Mg, and Ca from leaching reaction at NUKON and concrete after passivation of metal specimens.

• Journal of Animal Environmental Science
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• v.16 no.3
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• pp.215-226
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• 2010

The pig slurry leachate was dark brown-colored solution that leaches out of woodchip trickling filter. The purpose of this research was to investigate the effect of pig slurry leachate and byproduct on growth characteristics of leaf lettuce in hydroponics culture. The effects of addition of fish meal, bone meal and crab shell for the growth of leaf lettuce were investigated. Leaf lettuce were grown in each of six combination treatment solutions; slurry leachate, slurry leachate + fish meal, slurry leachate+bone meal, slurry leachate + crab shell and chemical hydroponic solution for lettuce based on EC content. The chemical nutrient solution was the solution of National Horticulture Research Station for the growth of lettuce. The all of nutrient solution was adjusted 1.5 mS/cm in EC in hydroponics culture. 1. The pH level of leachate of trickling filter was increased and EC decreased gradually during treatment. Pig slurry leachate was low in suspended solids (SS), phosphorus (P), but rich in potassium (K). 2. The plot of slurry leachate (SL) was lowest in the growth characteristics of lettuce. The leaf length and width of lettuce treated with mixture plot of slurry leachate and fish meal (SL + FM) was higher compared with plot in slurry leachate. The chlorophyll reading was reduced in plot treated with slurry leachate, but that in plot of SL+FM was similar compared with control plot. 3. The fresh weight of lettuce showed lowest in the plot treated with slurry leachate. The addition of fish meal increased the yield of comparing plot of slurry leachate, but plots of bone meal and crab shell addition were not significantly difference. The fresh weight of leaf lettuce in plot of SL+FM was 87% as 400.0g compared with control. In conclusion, the mixture solution of pig slurry leachate and fish meal could be used as a nutrition solution of organic lettuce hydroponics.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2002.05a
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• pp.22-22
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• 2002

본 연구에서는 교량, 발전소, 산엽체의 시설물 둥 대형 옥외 설치 구조물의 부식방지를 위해, 전류 인가형 부식 방지 장치를 개발하였다. 기존의 전극기판(anode base)은 pve로 만들 어져 있어서, 옥외에 설치된 상태에서 쉽게 열화되어 부스러지며, 비 갠 후 시설물의 일부에 물기가 남아 있는 부식 환경하에서도 플라스틱 기판은 물기가 쉽게 제거되어 이마 건조된 상태가 된다. 이 경우에는 기판을 통해 부식방지 전류를 흐르게 할 수가 없기 때문에 희생 양극의 임무를 수행할 수가 없으며, 시설물이 부식되는 단점이 있다. 본 연구에서 개발한 흡습성 기판은 기존의 pve 기판의 단점을 개선한 것으로, 대기 중에 방치해도 수명이 영구적이며, 다공질이기 때문에 흡습성이 있어서 비 캔 후에도 기판 내부와 표면에 물기가 남아 었다. 따라서, 비 캔 후 부식환경에서도 부식 방지 전류를 흐르게 할 수가 있어서 희생양극의 업무를 수행할 수 있다. 본 연구에서는 옥외 구조물에 대한 방식 특성을 평가하기 위하여, 세라믹 기판을 부착하고 전류 측정을 하기 위한 철판(보통탄소강)구조물을 아래와 같이 제작하였다. 구조물의 $가로{\times}세로$ 크기는 $450mm{\times}450mm$ 이며, 구조물의 중앙에 세라믹 또는 pve Anode 기판을 부착 하였다. 살수 후 전류의 측정 위치는 구조물의 Anode 기판 중심에서 100mm 떨어진 지점 4 곳에 부착하였다. 본 연구에서 개발한 세라믹 가판의 경우와 기존의 pve 기판의 경우를 비 교 실험한 결과, 전자의 경우는 120분 경과 후에도 $70~80\mu\textrm{A}$의 많은 양의 전류가 흐르는 것으로 밝혀졌으며, 후자의 경우는 120분이 지난 후에는 전류가 전혀 흐르지 않는 것올 알 수 있다. 따라서, 기존의 pve 보다 세라믹 기판의 경우가 수분 흡수율이 높아 더 오랫동안 전류를 흐르게 하여 방식성이 개선된 것으로 판단된다.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2011.04a
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• pp.144-147
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• 2011

동시다발적인 산불발생시 한정된 진화자원을 효과적으로 운영하여 산불피해를 최소화하기 위해서는 산불상황에 맞는 진화자원 투입과 배치가 이루어져야 한다. 이를 위해서는 진화자원 투입 및 운영 의사결정을 할 수 있도록 각 진화자원별 진화능력단위에 대한 평가가 이루어져야 한다. 하지만 아직 국내 외적으로 산불진화자원에 대한 진화능력단위 산정에 관한 연구가 이루어져 있지 않다. 따라서 본 연구에서는 우리나라 진화자원을 중심으로 진화능력단위 기준 설정과 함께 각 진화자원별 진화능력단위를 산정하였다. 우리나라 진화자원은 크게 지상진화자원과 공중진화자원으로 구분됨으로 지상진화에 투입되는 주요 진화자원인 등짐펌프 및 불갈퀴 등 손도구를 이용하는 진화인력과 산불진화차량, 이동식 동력살수장치와 산불진화헬기로 구성되는 공중진화자원에 대해 진화효과를 분석, 능력단위를 산정하는 방법을 제시하였다.

• Journal of the Korea Institute of Building Construction
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• v.17 no.2
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• pp.127-134
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• 2017

In this study, moist curing equipment was used in the exist gang-form system. By achieving sufficient spray curing, the quality of the concrete was improved and the cracking occurred in building's side wall was decreased. The following results could be made as the conclusion. For the compressive strength, all zones showed the similar results. Comparing with the zone without using moist curing equipment, the zone used moist curing equipment showed higher rebound hardness results. For the cracking, the zone utilized moist curing equipment showed the cracking averaged as 6.6 m and the zone without using moist curing equipment showed the cracking averaged as 10.3m. The effectof reducing cracking by utilizing moist curing equipment is about 36 %. Using moist curing equipment is considered as a good solution to reduce the cracking in the structure. Considering all the factors analysed, using moist curing equipment improved the quality of the concrete and decreased the cracking. When this equipment was used in the construction site, it is expected that the construction periodcan be shrunk and the ratio of defect caused by drying shrinkage can be decreased. In this research conditions, The 0.3mm sized moist curing equipment provided the most desirable results on concrete quality and preventing cracking.

• Fire Science and Engineering
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• v.30 no.3
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• pp.31-40
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• 2016

Recently, a curtain wall system was applied to skyscrapers to prevent fire spreading along the vertical direction due to stack effect and outside air flow when a fire breaks out in skyscraper. Conventional sprinklers cannot prevent the spread of fire to the upstairs areas, which increases the loss of life and property. In this study, a water curtain nozzle that creates wider water coverage on the surface of glass and can prevent the spread of fire to the upstairs areas was developed. The spray pattern of the water curtain nozzle was compared with that of a sprinkler to determine performance of the water curtain nozzle. A fire experiment was constructed on the second floor to verify performance of the water curtain nozzle in preventing the spread of fire to the upstairs areas. The fire and watering experiment proved that the water curtain nozzle prevented more effectively the spread of fire than the conventional sprinkler. The position of first crack and critical temperature of fracture were also analyzed using numerical analysis.

• 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.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.2
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• pp.230-237
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• 1996

The objective of the present study is to evaluate organic removal efficiencies, nitrogen removal efficiencies, kinetic constant, sludge production rates, oxygen requirements, and optimum treatment renditions for recycling water treatment of aquaculture by using a trickling filter process. When the loading rates were $0.500\~0.082kg\;COD/m^3/day$ and $0.271\~0.044kg\;NH_4^+-N/m^3/day$, SCOD and ammonia removal efficiencies were $74.5\~84.0\%$ and $43.7\~61.8\%$, respectively. The maximum removal rate of ammonia was 119.5 mg/L/day. Observed cell yield coefficient in the trickling filter reactor was 0.572 kg VSS/kg $BOD_{rem}$. When the hydraulic loading rate was $6.712\~40.341m^3/m^2/day$, oxygen uptake rate was $1.33\~7.22\;mg\;O_2/L/hr$.