• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2013년도 춘계학술발표대회
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• pp.311-314
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• 2013

본 논문에서는 일본의 (주) 동경전력이 공개한 후쿠시마 제 1 원자력발전소 2 호기 원자로건물 지하에 위치한 S/C (Suppression Chamber) 주변의 Vent 관 조사 동영상들을 분석하였다. S/C 는 donut (환형) 모양의 구조물로 PCV (격납용기) 와 연결된 8 개의 Vent 관을 통해 원자로의 압력을 억제한다. 후쿠시마 사고 원자로의 용융 핵연료를 인출하기 위해서는 원자로 압력용기 및 PCV에 물을 채워서 방사선 선량율을 떨어뜨려야 한다. 물을 채운 후에 누설이 되면 안되기 때문에, PCV 와 S/C 사이에 연결된 Vent 관에 대한 방사능 오염수의 누설지점을 찾는 것이 중요하다. 이를 위한 사전공정으로 (주) 도시바의 4 족보행 로봇 탑재 카메라를 이용하여 8 개 Vent 관 모두를 육안 검사하였다. (주) 동경전력이 공개한 영상을 분석한 결과 고선량 감마선에 의한 Speckle 들이 관측되었다. 본 논문에서는 이러한 Speckle 분포의 특성을 분석하여 S/C 와 PCV 를 연결하는 8개 Vent 관중 방사능 오염물질이 많은 곳을 특정하고자 하였다.

• 농업과학연구
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• 제42권4호
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• pp.325-333
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• 2015

The ventilation systems composed three types of side vent (roll-up) 'SV', side vent+roof vent 'SV+RV', and side vent+roof fan 'SV+RF' with 7.5 m spacing, with specific set point temperatures for ventilation: SV ($35^{\circ}C$ open / $33^{\circ}C$ close), SV+RV or SV+RH ($35^{\circ}C$ open/$33^{\circ}C$ close for root ventilation and $37^{\circ}C$ open / $35^{\circ}C$ close for side vent). In the treatment of SV+RV, although the average daily maximum temperature inside the greenhouse temporarily increased by $38-40^{\circ}C$, thermal stress by high temperature did not occur and the disease incidence (%) of powdery mildew and downy mildew on the oriental melon were 25 - 75% lower than in the conventional SV treatment. In the SV treatment, the disease incidence (%) of powdery mildew and downy mildew were 1.4 - 7.7% and 4.2 - 15.9% for 'Deabakkul', and 20.3 - 22.8% and 2.8 - 11.3%, for 'Ildeungkkul'. The yield for one month was higher in the treatment of SV+RV than those in other treatments, with values of 2,105 kg/10a for 'Deabakkul' and 2,537 kg/10a for 'Ildeungkkul'. The simultaneous treatment with side vent and roof vent resulted in 16.2% higher yield (18.1% higher marketable yield) than that in the SV treatment for 'Deabakkul'.

• 한국안전학회지
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• 제14권3호
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• pp.40-47
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• 1999

A numerical study on gaseous explosion was carried out to predict the transient pressure behavior with the partial rupture in confined vessels. Equations, assumptions and solutions for central ignition of premixed gases in closed spherical vessels are proposed with various equivalence ratios of gas fuel, as $CH_4$ and $C_3H_8$, vent areas and vent opening pressures. Given vent opening pressure in a vessel, the magnitude of second peak pressure results from the vent areas and burning velocity, varied by equivalence ratio of gas fuel. In a living room of an apartment, the higher second peak pressure than the vent pressure is not appeared due to its large window areas. As vent opening pressure is higher, the larger damage by gaseous explosion is expected and the larger vent area is necessary for relieving the damage. In the same concentration, the gaseous explosion by propane rather than methane shows the larger damage due to its higher adiabatic flame temperature and equivalence ratio.

• 설비공학논문집
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• 제14권3호
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• pp.247-253
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• 2002

In this study, reduced-scale experiments were conducted to analyze smoke movement in tunnel fire with roof vent. The 1/20 scale experiments were carried out under the Froude scaling using gasoline pool fire ranging from 7.3 to 15.4 cm in diameter with total heat release rate from 1.0 to 8.46kw. In case of 1 m high vent, smoke front reached to the tunnel exit at about 16 sec delayed with ventilation. The delay time grew longer with the vent height. The temperature after the vent was lower than that without the vent. The exit temperature declined maximum of $20^{\circ}C$ after passing the vent. It was confirmed that the thickness of smoke layer was maintained uniformly under the 25% height of the tunnel through the visualized smoke now by a laser sheet and the digital camcorder.

• 한국식품저장유통학회지
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• 제17권5호
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• pp.581-585
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• 2010

플라스틱 컨테이너의 통기공 비율에 따른 딸기의 예냉효과와 저장 중 품질비교를 위하여 플라스틱 컨테이너($520mm{\times}355mm{\times}182mm$)의 하단부와 양측면부의 면적당 통기공 비율을 5%, 10%, 15%, 20%로 제작하여 컨테이너 당80%의 체적비율로 적재한 후 차압예냉을 실시하고 $5^{\circ}C$에서 현 포장방법에 의거한 저장실험을 수행하였다. 딸기의 예냉 전 품온은 평균 $18^{\circ}C$였으며, 목적 품온 $2^{\circ}C$에 도달하는 시간은 처리구별로 20%는 1시간 9분, 15%는 1시간 13분, 10%는 2시간 2분 5%는 2시간 51분이 소요되었다. 예냉이 완료된 딸기는 PP 용기에 포장하여 $5^{\circ}C$ 저장에 저장하면서 중량감소율, 짓무름, 곰팡이 발생률 및 표면경도를 측정하였다. 중량감소율, 짓무름 발생률 및 부패율은 20% 개공율 처리구가 가장 높았던 반면 15% 개공율 처리구가 가장 낮았으며 5%와 10% 개공율 처리구는 중간적인 수준을 유지하였고, 표면경도에서는 처리구간 차이가 나타나지 않았다.

• 한국재료학회지
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• 제14권12호
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• pp.870-875
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• 2004

Heat flow characteristics in the newly developed Wave Heat Sink were analyzed under natural and forced convections by Icepak program using the finite volume method. Temperature distribution and thermal resistance of Wave Heat Sink with/without air vent hole on the top of fin were compared with those of a commercial Al extruded heat sink(Intel Heat Sink). Under the natural convection, the maximum temperature was $45.1^{\circ}C$ in the air vent hole typed Wave Heat Sink, which was superior to that of Intel Heat Sink. The thermal resistance was $2.51^{\circ}C/W$ in the air vent hole typed Wave Heat Sink, and it changed to $2.65^{\circ}C/W\;and\;2.16^{\circ}C/W$ with changes of gravity direction and fin height, respectively. Under the forced convection, the maximum temperature became lower than that under the natural convection. In addition, the thermal resistance lowered in the air vent hole typed Wave Heat Sink with higher fin height and it decreased with increasing the air flux.

• 소성∙가공
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• 제24권4호
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• pp.293-298
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• 2015

A safety vent is crucial to protect its user from unpredictable explosions caused by increasing internal pressure of the lithium-ion batteries. In order to prevent the explosion of the battery, a safety vent rupture is required when the internal pressure reaches a critical value. In conventional manufacturing, the cap plate and the safety vent are fabricated separately and subsequently welded to each other. In the current study, a manufacturing process including a backward extrusion and coining process is suggested to produce an integral safety vent which also has the benefit of increasing production efficiency. FE simulations were conducted to predict the rupture pressure and to design the safety vent using a ductile fracture criterion and the element deletion method. The critical value, C, in the ductile fracture criterion was obtained from uniaxial tensile tests with an annealed sheet of 1050-H14 aluminum alloy. Rupture tests were preformed to measure the rupture pressure of the safety vent. The results met the required rupture pressure within 8.5±0.5 kgf/cm². The simulation results were compared with experimental results, which showed that the predicted rupture pressures are in good agreement with experimentally measured ones with a maximum error of only 3.9%.

• 한국광물학회지
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• 제27권4호
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• pp.169-181
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• 2014

우리나라는 2008년부터 심해저 광물자원 확보를 위하여 남서태평양 통가국 EEZ 내 Tofua arc의 해저 화산열도에서 해저열수광상에 관한 조사를 지속적으로 수행하고 있다. 통가국 라우분지 TA 25 해저산에서 해저 열수 활동에 의하여 형성된 광물들의 특성과 분포를 규명하기 위하여 X선회절분석, 주사전자현미경 관찰, X선형광분석과 유도결합 플라즈마 방출분광분석을 실시하였다. 연구에 사용된 시료는 TA 25 해저산 주변에서 채취된 7개의 코어 시료와 9개의 해저퇴적물 시료이다. 열수분출구 모든 지역에서 중정석, 섬아연석, 클리노클레이스 등이 존재하고, 열수분출구 A 지역에는 석고, 스멕타이트 및 카올린 광물, 열수분출구 B와 C 지역에는 스멕타이트, 카올린 광물, 황동석과 황철석, 열수분출구 D 지역에는 석고, 황동석, 황철석, 침철석 등이 분포한다. 점토부분에 대한 분석 결과 칼데라 중심부 지역을 제외한 모든 지역에서 스멕타이트와 소량의 카올리나이트가 포함되어 있는 것으로 보아 이질변질작용에 해당하는 열수변질이 있었음을 알 수 있다. 열수분출구 B, C, D 지역은 여러가지 종류의 황화광물과 비소화광물이 존재한다. 광물조성, 주성분과 미량성분 분석 결과로 판단할 때 열수분출구 B, C, D 지역이 비교적 강한 고온의 열수변질작용, 열수분출구 A와 칼데라 중심부 지역은 열수의 영향을 적게 받았거나 저온의 열수변질작용을 받은 것으로 판단된다. 추후 열수광상 탐사는 열수분출구 B, C, D 지역에서 수행되어야 할 것으로 여겨진다.

• Animal Systematics, Evolution and Diversity
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• 제35권1호
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• pp.30-32
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• 2019

The brachyuran crab Bythograeidae Williams, 1980 is common in hydrothermal vent fields worldwide and has recorded to sixteen species of six genera. In this study, we firstly determined the cytochrome c oxidase subunit 1 (CO1) DNA barcodes for the fifth species of Austinograea, A. hourdezi, from hydrothermal vent regions of the North Fiji Basin in southwestern Pacific Ocean. All CO1 DNA barcodes of A. hourdezi were identical. The interspecies variations of three bythograeid genera were 10.9-13.3% for Austinograea, 6.6-15.7% for Bythograea, and 9.7% for Gandalfus. These results would be helpful to understand taxonomy of brachyuran crabs living in hydrothermal vent fields using CO1 DNA barcodes.

• 자동차안전학회지
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• 제11권1호
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• pp.23-29
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• 2019

Recently, use of composite materials has been increasing for body structures and chassis parts in the car industry because of weight reduction effect and excellent mechanical thermal characteristics. However, application of composite materials in brake system is very difficult because it is hard to obtain enough brake performance due to low heat storage capacity of the composite materials. In this paper, we will present new carbon ceramic composite disc with high flow characteristic. To obtain this characteristic, new vent structures were designed by using ARIZ method and substance-field model analysis. The flow effect of these vent structures on the brake performance was verified by pugh matrix and cooling test. The test results show improvement of cooling performance up to $30^{\circ}C$. Finally, These results will improve brake the reliability of the brake performance for the high performance vehicles and electric vehicles.