• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2006년도 추계학술대회
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• pp.54-57
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• 2006

Structure H formation experiments were conducted in a semi-batch stirred vessel using methane as the small guest substance and neohexane(NH), tert-butylmethylether(TBME) and methylcyclohexane(MCH) as the large molecule guest substance (LMGS). The results indicate that the rates of gas uptake and induction times are generally dependent on the magnitude of the driving force. When tert-butyl methyl ether is used as the LMGS rapid hydrate formation, much smaller induct ion time and rapid decomposition can be achieved. Liquid-liquid equilibrium (LLE) data for the above LMGS with water have been measured under atmospheric pressure at 275.5, 283.15K, and 298.15K. It was found that TBME is the most water soluble followed by NM and MCH. The solubility of water in the non-aqueous liquid was found to increase in the following order: MCH

• 한국초전도저온공학회:학술대회논문집
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• 한국초전도저온공학회 2001년도 학술대회 논문집
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• pp.48-49
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• 2001

Cryogenic technology is one of the key technologies for fusion reactor equipped with superconducting coil for plasma confinement. The KSTAR(Korea Superconducting Tokamak Advanced Research)Project is in progress since 1996. Major parameters of the KSTAR tokamak are : major radius 1.8m, minor radius 0.5m, toroidal field 3.5 Tesla and plasma current 2MA with a strongly shaped plasma cross-section and double -null diverter. Considering practical engineering constraints, the KSTAR device is designed for a pulse length of 300 sec in up-graded operation mode but in the initial configuration would provide a pulse length of 20 sec provided by the poloidal coil system in base-line operation mode. The cryogenic system is composed as follows : cold box, helium compressor system, distribution box, helium gas buffer tank, helium gas purifying system, gas recovery system, liquid helium storage dewar, current lead box, current bus line and liquid nitrogen storage tank.

• 한국환경과학회지
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• 제16권12호
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• pp.1325-1335
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• 2007

The utility of soil-gas surveys is directly proportional to their accuracy in reflecting and representing changes in the subsurface concentrations of source compounds. Passive soil-gas vapor-phase is merely a fractional trace of the source, so, as a matter of convenience, the units used in reporting detection values from EMFLUX surveys are smaller than those employed for source-compound concentrations. According to the Leaking Underground Storage Tank(LUST) Program Annual Report, approximately 16 U.S. million dollars were spent for environmental site investigations at over 1,600 Underground Storage Tank(UST) sites and approximately over 1,000 acres of land was characterized and remediated in the State of Illinois in the year of 2003 alone. The main purpose of this study is to propose an idea to significantly reduce the site investigation cost by utilizing a passive soil-gas survey and conventional intrusive drilling method and to fully define the three dimensional characteristics of subsurface contamination from two industrial drycleaning facilities.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회B
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• pp.3169-3174
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• 2008

Future power plants will be required to adopt some type of carbon capture and storage (CCS) technologies to reduce their CO2 emissions. One of distinguished CCS techniques expected to resolve the green house effect is to apply the oxy-fuel combustion technique to power plant, and a lot of research/demonstration programs have been going on in the world. In this paper, CO2-capturing power plants based on gas turbine and oxy-fuel combustion are investigated over several types of configurations. As a prior step, simulation model for 500 MW-class combined cycle power plant was set and was used as a reference case. The efficiencies of several power plants was compared and the advantages and disadvanteges was investigated.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2017년도 춘계학술논문요약집
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• pp.153-154
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• 2017

The thermal analysis of transportation and storage cask for SNF was conducted during short term loading operations for forced gas drying condition. The fuel cladding temperature in 6 regions of SNF in the cask during the short term loading operations for forced gas drying condition is shown in the Fig. 3. The thermal analysis results of calculated maximum cladding temperature in each process demonstrate that operating scenario of TFD in detailed design maintain well below the temperature limits of $400^{\circ}C$.

• Nuclear Engineering and Technology
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• 제53권5호
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• pp.1464-1478
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• 2021

Selective Production of Exotic Species is an innovative plant for advanced nuclear physic studies. A radioactive beam, generated by using an UCx target-ion source system, is ionized, selected and accelerated for experimental objects. Very high vacuum conditions and appropriate safety systems to storage exhaust gases are required to avoid radiological risk for operators and people. In this paper, Failure Mode, Effects, and Criticality Analysis of a preliminary design of high activity gas recovery system is performed by using a modified Fuzzy Risk Priority Number to rank the most critical components in terms of failures and human errors. Comparisons between fuzzy approach and classic application allow to show that Fuzzy Risk Priority Number is able to enhance the focus of risk assessments and to improve the safety of complex and innovative systems such as those under consideration.

• 한국가스학회:학술대회논문집
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• 한국가스학회 2003년도 추계학술발표회 논문집
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• pp.203-208
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• 2003

• 한국포장학회지
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• 제24권3호
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• pp.113-120
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• 2018

The one-way gas valve developed in this study was designed to prevent the breakage of packages from increased internal pressure, which is a problem in packaged Kimchi, and simultaneously reduce the outflow of the offodor release. The effect of the one-way gas valve on the headspace atmospheric compositions was investigated in the packaging system. The changes of atmospheric compositions and quality factors of Kimchi, such as $CO_2$ accumulation, pH, titratable acidity, and salinity, were measured during a 4-week storage period at $4^{\circ}C$. The Kimchi package with the one-way gas valve dramatically reduced pressure build-up in the pouch by allowing the controlled flow of gas to the atmosphere. In addition, the package design allows the possibility of controlling the gas generated from Kimchi by adjusting the viscosity of the open pressure control oil. The one-way gas valve did not affect the sensory characteristics of Kimchi products during the storage period. Furthermore, the deodorizing capability of the activated carbon contained in the one-way gas valve effectively reduced the off-odor of Kimchi products released along with carbon dioxide. The novel one-way gas valve is considered to be an active packaging system that can solve major problems of expansion and off-odor leakage in the packaging of Kimchi.

• 한국식품영양과학회지
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• 제44권7호
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• pp.1072-1078
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• 2015

고품질 수출용 파프리카 생산을 위한 파프리카의 미생물학적 안전성을 확보하고 품질 유지를 위해 75 ppmv 이산화염소 가스 훈증 처리 후 $8{\pm}1^{\circ}C$에서 30일 동안 저장하면서 미생물 수 및 품질 변화를 측정하였다. 이산화염소 가스 훈증 처리 후 총 호기성 세균과 효모 및 곰팡이 수는 대조구와 비교하여 각각 1.62, 1.45 log CFU/g의 미생물 수 감소를 보였으며, 이러한 효과는 저장 30일 동안 지속되었다. 파프리카의 중량감소율은 저장 중 대조구와 처리구 모두 증가하는 경향을 나타냈으나 저장 30일 후 처리구가 대조구보다 1.08% 더 낮게 유지되었다. 저장 중 당도, 총 페놀 함량, 비타민 C 함량 및 경도는 이산화염소 가스 처리 유무와 상관없이 차이를 보이지 않았다. 당도와 총 페놀 함량은 저장 기간동안 큰 변화를 보이지 않았으나 비타민 C 함량과 경도는 저장 중 감소하는 경향을 나타내었다. 또한 이산화염소 가스 훈증 처리는 파프리카의 Hunter 색도 값에 부정적인 영향을 미치지 않았고, 관능평가에 있어서도 외관적 상태, 신선도, 종합적 기호도 측면에서 대조구보다 높은 점수를 나타냈다. 따라서 본 연구 결과 수확 후 파프리카에 75 ppmv 이산화염소 가스 훈증 처리는 저장 중 파프리카의 품질 변화를 최소화하면서 미생물학적 안전성을 확보할 수 있는 효과적인 수확 후 기술이라고 판단된다.

• 한국가스학회지
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• 제25권4호
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• pp.10-18
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• 2021

대수층에 이산화탄소를 저장하는 기술은 높은 저장능력과 경제성 때문에 지구 온난화를 완화하는 가장 효율적인 방법중 하나이다. 포항분지 해상 중소규모 CO₂ 지중저장 실증은 심부 대수층에 CO₂ 를 저장하는 사업으로 대규모 CO₂ 저장에 필요한 실증요소 기술을 개발하고 검증하는데 목적이 있다. 이 사업의 초기 설계 단계에서 도전적으로 직면하는 문제중 하나는 CO₂ 를 주입하는 주입관에서 주입성을 확보하는 것이다. 이러한 문제를 해결하기 위해 주입량, 압력, 온도, CO₂ 의 상변화 및 그에 따른 열역학적인 물성값 등을 계산하여 주입 조건을 계산하였다. 본 연구를 위해 기체 상태의 CO₂ 를 주입관에 주입하여 기체-액체-초임계 상의 상변화 거동 및 유동 특성의 변화를 OLGA 프로그램을 이용하여 수치해석적으로 분석하였다. 결과를 통하여 CO₂ 의 주입 시스템과 대수층의 공저압을 연계하는 주입조건을 제시하였다.