• 한국산업융합학회 논문집
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• 제10권2호
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• pp.97-104
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• 2007

In different approaches were extracted from evening primrose seed by supercritical fluids carbon dioxide and for comparison with hexane as solvent. The extracts have been analyzed qualitatively and quantitatively to evaluate yield and selectivity of ${\gamma}$-linolenic acid. The yields extracts with supercritical fluids carbon dioxide were higher than those with hexane. When this process produces commercially, will get a many economic profit.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 추계 학술발표회 논문집
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• pp.461-464
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• 2006

Recently, as structures become bigger and higher, it is needed that high strength, high flow and high durability concrete. Demanding of High performance concrete that equality is maintained without material separation while flow, strength is increased by using low W/C rate and admixture, carbonation does not occur because of dense filling and has high durability is increasing rapidly. Because this high performance concrete is superior to general concrete in workability and durability, it is widely used in many construction and engineering works fields. However, it is reported that when it was exposed in fire, violent explosive spalling would be happened. Therefore, the purpose of this study evaluates explosive spalling properties of fire damaged high performance concrete according to the heating time.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 1997년도 International Symposium on Fire Science and Technology
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• pp.260-268
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• 1997

The safety of LPG vessel storage has been simply designed and controled with blast wave barrier structure concept regardless of its quantity or hazardous situation. The limit of regal controls on LPG vessel storage need to be identified in terms of safety buffer distance from LPG explosion. The level of overpressure effect and heat radiation In the safety structure and neighbouring human activity required to be estimated to find the gap between existing controls on such storage. To this content the paper discuss the issues on the approach In the blast wave barrier and safety separation distances.

• 한국전산유체공학회지
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• 제17권2호
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• pp.11-20
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• 2012

In this paper, the authors test various open codes and commercial codes based on CFD technology on the wind field around the complex terrain, which is a very important transport physics in the event of forrest fire. To study the physical mechanism inside the transition from surface fire to crown fire, the wake flow behind a parallel array of trees is studied numerically to show the flow separation in the turbulent boundary layer. Two sites near to Kunsan National University are chosen for the measurement of real wind field, and obtained data are compared with those from various computational codes such as Wind-Ninja, NIST-FDS, ANSYS-CFX, and ANSYS-FlUENT, etc. Through this research, feasibility and accuracy of the present CFD codes are investigated quantitatively, compared with the measured data with AWS.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 춘계학술대회 논문집 전기설비전문위원
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• pp.18-22
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• 2009

In this paper, we are develop specifications light-way lighting appliance for efficient construction. Analyzed wide application and connection regulation. Also, flickering circuit Presented separation, arrangement, mounting instruction. Incandescent lamp occurs much heat. Therefore, establishment of enough electric light interval is required. Voltage of discharge lamp does by below 300v, and provide so that a person is not can may touched.

• 대한안전경영과학회지
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• 제17권1호
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• pp.75-84
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• 2015

Successful development of weapon systems requires a stringent verification and validation (V&V) process due to the nature of the weapons in which continual increase of operational capability makes the system requirements more complicated to meet. Thus, test and evaluation (T&E) of weapon systems is becoming more difficult. In such a situation, live fire tests appear to be effective and useful methods in not only carrying out V&V of the weapon systems under development, but also increasing the maturity of the end users operability of the system. However, during the process for live fire tests, a variety of accidents or mishaps can happen due to explosion, pyro, separation, and so on. As such, appropriate means to mitigate mishap possibilities should be provided and applied during the live fire tests. To study a way of how to accomplish it is the objective of this paper. To do so, top-level sources of hazard are first identified. A framework for T&E is also described. Then, to enhance the test range safety, it is discussed how test scenarios can be generated. The proposed method is based on the use of the anticipatory failure determination (AFD) and multiple event tree analysis (ETA) in analyzing range safety. It is intended to identify unexpected hazard components even in the environment with constraints. It is therefore expected to reduce accident possibilities as an alternative to the traditional root-cause analysis.

• 한국방재안전학회논문집
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• 제16권1호
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• pp.71-80
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• 2023

연료전지는 저탄소 발전원으로 주유소 내 연료전지를 설치 시 분산에너지와 전기차 충전인프라를 확충할 수 있다. 주유소 내 연료전지 설치 시 안전성 확보를 위하여 국‧내외 주유소 및 연료전지의 사고데이터를 기반으로 사고시나리오를 도출하고 사고피해예측을 위한 정량적 위험성평가를 실시하였다. 최악의 사고시나리오가 아닌 현실적으로 발생 가능한 화재 및 폭발사고의 피해범위를 산출하고, 피해영향을 분석한 결과 주유기로부터 9.0 m, 주유 중 차량으로부터 15.5 m, 통기관으로부터 4.1 m, 연료전지의 정압기 등 가스조정장치로부터 1.1 m 이상 이격 시 사고로 인한 심각한 피해 위험을 낮출 수 있는 것으로 나타났다. 이러한 연구 결과는 주유소 내 연료전지 배치 및 사고피해를 경감할 수 있는 안전대책 수립에 활용할 수 있을 것으로 기대된다.

• Geomechanics and Engineering
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• 제27권6호
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• pp.537-550
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• 2021

There are various technical problems need to be solved in the construction process of pre-setting an isolation wall into a double lane in the outburst prone mine. This study presents a methodology that pre-setting an isolation wall into a double lane without a coal pillar. This requires the excavation of two small section roadways to dig a wide section roadway, followed by construction of the separation wall. During this process the connecting lane is reserved. In order to ensure the stability of the separation wall, the required bearing capacity of the isolation wall is 4.66 MN/m and the deformation of the isolation wall is approximately 25 cm. To reduce the difficulty of implementing support the roadway is driven by 5 m/d. After the construction of the separation wall, the left side coal wall is brushed 1.5 m to make the width of the gas roadway reach 2.5 m and the roadway support utilizes anchor rod, ladder beam, anchor cable beam and net configuration. During construction, the concrete pump and removable self-propelled hydraulic wall mold are used to pump and pour the concrete of the isolation wall. In the process of mining, the stress distribution of coal body and isolation wall is detected and measured on site. The results demonstrate that the deformation of the surrounding rock of roadway and separation of roof in the roadway is small. The stress of the bolt and anchor cable is within equipment tolerance validating their selection. The roadway is well supported and the intended goal is achieved. The methodology can be used for reference for similar mine gas control.

• 한국위성정보통신학회논문지
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• 제8권3호
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• pp.52-57
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• 2013

본 논문은 컬러 영상의 색상분석 기반의 화염 검출 알고리즘에 최적인 컬러모델을 도출하여 화재감시 시스템에 적용하기 위한 컬러모델의 화염 색상 비교 분석에 대하여 기술한다. 기존 화재검출 알고리즘에서 많이 사용되는 RGB, YCbCr, CIE Lab, HSV 국제 표준 컬러모델에서 화염과 비화염 영역간의 색상 분리도 특성을 영상의 히스토그램 교차 분석(Histogram Intersection) 기법을 사용하여 정량화하고 분석한다. 4가지 국제 표준 컬러모델에 대한 히스토그램 교차 분석 결과, YCbCr 컬러모델의 평균 히스토그램 교차값이 0.0575로서 화염과 비화염간의 색상 분리도가 가장 우수한 컬러모델임을 확인하였으며, 각 컬러모델을 구성하는 12개 성분들 중에서는 청색차(Cb) 성분, 적색(R) 성분, 적색차(Cr) 성분이 각각 0.0433, 0.0526, 0.0567 로서 화염과 비화염 영역의 색상 분리도 특성이 매우 우수하여, 색상 분석 기반의 화염 검출에 가장 최적이며 실용적인 컬러모델과 성분임을 확인하였다.

• 한국화재소방학회논문지
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• 제25권4호
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• pp.48-55
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• 2011

차동식 스포트형 공기 팽창식 열감지기를 인공 가속열화 시켰을 때 발생하는 고장 원인에 대하여 분석하였다. 감지기에 고장이 발생하는 원인은 감열실 금속을 고정하는 접합재(binder)가 플라스틱 몰딩(moulding)에서 분리되어 발생하는 고장과, 감열실 금속과 다이어프램 금속을 고정하는 플라스틱 몰딩에 균열이 발생되는 고장으로 확인되었다. 고장이 발생하지 않은 감지기는 감열실 금속 및 다이어프램 금속이 플라스틱 몰딩에 접합재로 완전히 부착되어 있었다. 또한 2010G 감지기는 접합재의 기계적 강도를 향상시키기 위하여 접합재에 유리강화섬유가 추가되었음이 확인되었다. 감지기 종류별에 따른 플라스틱과 접합재의 밀도에는 큰 차이가 없었다. 그러나 감지기의 플라스틱에 대한 열중량분석(TGA) 결과, 제작년도는 같지만 제조회사가 다른 2005A와 2005B의 플라스틱 열적특성이 동일하지 않은 것으로 확인되었다.