• Electric Engineers Magazine
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• v.186 no.2
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• pp.51-57
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• 1998

전압정도는 계통이 정상운전조건에서나 외란이 발생한 후에 모든 모선전압이 허용범위내를 유지할 수 있는 전도이다. 외란, 부하의 증가 또는 계통의 조건변화로 전압이 점차로 제어 불가능하게 떨어질 때를 계통이 전압 불가능 상태라 한다.

• Korean journal of food and cookery science
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• v.13 no.1
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• pp.40-46
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• 1997

This study was conducted in order to determine the effect of preparing conditions(refrigerating and freezing of dough, dough size, frying temperature, kneading degree and ingredient amount) on the dehydration, absorbed oil content and sensory characteristics of Yackwa. There were no significant differences on the dehydration, absorbed oil content and sensory characteristics between the control Yackwa and those prepared by refrigerating and freezing of dough. In the dough size (large, medium, small), dehydration and absorbed oil content was increased as the size became smaller. It was shown that overall acceptability was high in medium size Yackwa. There were no significant differences on the dehydration of Yackwa under various frying temperature and kneading degree. On the other hand, absorbed oil content of Yackwa was decreased as the frying temperature became higher and kneading degree increased. Dehydration of Yackwa was increased as the amount of sesame oil, honey and sozu increased. There were no significant differences on the absorbed oil content of Yackwa as the amount of sesame oil increased. The absorbed oil content was increased as the amount of honey increased, whereas the absorbed oil content decreased as the amount of sozu increased. Shininess, softness, brittleness and oily taste was increased as the absorbed oil content increased in sensory evaluation of Yackwa prepared by different frying temperature, kneading degree and ingredients amount. It was shown that above preparing conditions affected the absorbed oil content and sensory characteristics of Yackwa.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.38-38
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• 2010

낮은 세기의 레이저와 정지한 전자가 반응하면 전자는 레이저 전기장 세기에 비례하여 가속되며 레이저의 파장과 같은 파장의 빛을 낸다. 반면, 레이저의 세기가 일정 수준을 넘으면 전자의 속도가 빛의 속도에 가까워지게 되어 가속이 둔화되는 현상이 나타나며, 더 이상 전기장의 세기와 가속도가 비례하지 않게 된다. 이러한 비선형적인 전자의 운동이 레이저 기본 파장의 조화파(harmonic)를 발생시키는데, 이를 상대론적 비선형 톰슨 산란(relativistic nonlinear Thomson scattering, RNTS)이라고 한다. 단일 전자를 가정한 경우 RNTS에 의해 아토초($10^{-18}$ 초) 길이의 X선 펄스가 발생하는 것이 시뮬레이션 연구를 통해 잘 알려졌다. [1] 그러나, 실제 실험에서 적용할 수 있는 것은 단일 전자가 아니라 고체, 플라즈마, 전자 빔 등의 전자 덩어리이다. 전자덩어리를 구성하는 각각의 전자가 아토초 펄스를 발생시더라도 각각의 펄스 간에 결맞음(coherence) 조건이 맞지 않으면 아토초 펄스는 발생되지 않는다. 또한, 강한 세기의 펄스를 얻는데도 결맞음은 중요하다. 이 연구에서는 결맞음 조건으로 얇은 타깃에 대한 거울 반사 조건, 즉 레이저가 얇은 타깃에 입사되며 거울의 반사 조건을 만족하는 위치에 검출기(detector)를 위치시키는 방법을 제안하였다. 박막이 충분히 얇을 경우 각각의 전자에 대하여 레이저가 발사되어 타깃에 맞고 검출되기까지의 시간이 거의 일치하게 된다. 거울 반사 조건에 의한 아토초 펄스 발생은 particle-in-cell 방법을 통한 시뮬레이션으로 검증되었다. 결맞음 조건을 위한 얇은 타깃으로는 박막과 나노선 배열(nanowire array)을 사용하였다. 전자들 간의 쿨롱(Coulomb) 힘은 결맞음이 유지되는 것을 방해하는데, 박막에 비해 나노선 배열이 쿨롱 힘의 영향을 적게 받기 때문에 결맞음이 더 잘 유지된다.

• Korean Journal of Food Science and Technology
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• v.45 no.2
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• pp.191-198
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• 2013

The storage quality of fresh Sulhyang strawberries packaged under modified atmospheres was investigated to examine the effect of high $O_2$ on the fruit. Fresh strawberries were packed into PP trays and top-sealed with PET/PP film. Initial gas compositions inside the packages were varied with air, 40% $O_2$/60% $N_2$, 60% $O_2$/40% $N_2$, and 80% $O_2$/20% $N_2$. Sealed packages in PE film bags with air and perforated PP trays were also used as another treatment and control, respectively. Quality attributes and viable cell counts of pathogenic bacteria were assessed during storage at $5^{\circ}C$ for 12 days. High $O_2$ concentration showed no significant effects on the physicochemical and microbial qualities of strawberries. Fruit packaged in PE film bags with 6-15% $O_2$ and 7-9% $CO_2$ during storage had the lowest viable cell counts of inherent microorganisms among the treatment samples. Growth of pathogenic bacteria was suppressed in perforated packages where molds occurred frequently. In an overall sensory aspect, the PE film packages exhibited higher scores than the others at the end of storage period. The experimental results suggested that gas-permeable film packaging with an appropriate combination of $O_2$ and $CO_2$ rather than gas-barrier tray packaging with an initially high $O_2$ concentration would be suitable for improving the storability of strawberries.

• Korean Journal of Food Science and Technology
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• v.32 no.3
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• pp.668-673
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• 2000

The influence of storage atmosphere on ethylene production, quality attributes and storage injury of 'Tsugaru' apples was investigated. Apples were stored in 1% $O_2+1%\;CO_2,\;1%\;O_2+3%\;CO_2,\;3%\;O_2+1%\;CO_2,\;3%\;O_2+3%\;CO_2$ and air at $0^{\circ}C$ for 5 months. Ethylene production was more suppressed by 1% $O_2$ than 3% $O_2$ atmospheres regardless $CO_2$ levels. The loss of flesh firmness and the decrease of titratable acidity were not significantly different among the storage atmospheres until 3 months of storage but more retarded by 1% $O_2$ than 3% $O_2$ atmospheres thereafter. Soluble solid content was unaffected by the storage atmosphere, but the content tended to be increased until 2 months of storage and then not varied. Ethanol content increased up to a peak level followed by a gradual loss during storage in CA but increased continuously in air. In the sensory evaluation after storage for 5 months, hardness, tartness and overall acceptability of apples stored in 1% $O_2$ atmospheres were significantly higher than those stored in the others. There was no fruit injury or off-flavor production resulting from the 1% $O_2$ atmospheres. The incidence of bitter pit was reduced as storage $O_2$ level decreased. The results show that the optimum conditions of CA storage for 'Tsugaru' apples are $0^{\circ}C$ and 1% $O_2+1{\sim}3%\;CO_2$.

• Proceedings of the Korean Vacuum Society Conference
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• 1999.07a
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• pp.237-237
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• 1999

전극폭 300um, 전극간격 100um, 격벽높이 130um로 자체 제작한 테스트 패널에서 방전개시전압과 최소 방전유지전압 사이에서 방전유지전압 변화에 따른 벽전하, 벽전압을 측정하였다. 이 실험에서는 Ne가스와 Ne-Xe 혼합가스를 이용하였다. 이 결과로부터 방전유지전압 변화에 따른 벽전하, 벽전압을 통하여 최적의 방전유지전압 조건을 결정할 수 있으며, 이는 AC-PDP의 효율 향상에 기여할 것으로 판단되어 진다.

• Proceedings of the Korean Vacuum Society Conference
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• 2000.02a
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• pp.203-203
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• 2000

VDS(Versatile Driving Simulator) 시스템을 이용하여 방전유지전압펄스의 휴지기 변화에 따른 공간전하의 거동과 벽전하, 벽전압 및 효율 특성을 연구하였다. 이때 휴지기 변화에 따른 실험을 위하여 방전유지전압의 진동수 및 duty ratio를 변화시켰고, 사용된 테스트 패널은 전극폭 260um, 전극간격 100um, 격벽높이 120um, 기압은 400Torr로 Ne-Xe(4%) 기체를 사용하였다. 이 결과로부터 방전유지전압펄스의 휴지기 변화에 따른 벽전하, 벽전압 및 효율 측정을 통하여 최적의 방전유지전압펄스의 조건을 결정할 수 있으며, 이는 AC PDP의 효율 향상에 기여할 것으로 판단되어 진다.

• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.109.2-109.2
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• 2011

바이오디젤의 생산은 원료유의 순도와 촉매 종류, 알코올의 양, 반응시간, 반응 온도와 같은 다양한 조건을 이용하여 최적의 조건을 찾아내는 것이 중요하며 이는 곧 생산단가와 직결된다. 바이오디젤 전환 시 고체촉매를 이용하면 후처리 공정의 단순화가 가능하며 글리세린의 순도가 약 98%로 매우 높아져 고부가 물질 생산 원료로 활용이 가능하다는 장점이 있으며 생산 단가를 4~20% 가량 낮출 수 있다. 본 연구에서는 바이오디젤의 경제적인 생산을 위하여 정제공정을 단순화 시킬 수 있는 방안으로 3종의 고체촉매를 이용하여 동 식물성 유지의 바이오디젤로 전환 실험을 수행 하였다. 촉매 활성화를 위하여 고체촉매를 $700^{\circ}C$에서 3~5시간 소성하고 동 식물성 유지를 이용 전이에스테르화 반응실험을 수행하여 30분 간격으로 시료를 수집 하였다. 실험 결과, 동물성 폐유지로부터 반응 120분 후에 최대 90% 이상의 지방산 메틸에스테르로의 전환율을 얻을 수 있었으며 식물성 유지인 팜유에서는 86%, 유채유에서는 64%의 전환율을 나타냈다. 동 식물성 유지의 초기 산가는 0.45~2mg KOH/g 사이로 나타났다.

• The Journal of the Convergence on Culture Technology
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• v.3 no.3
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• pp.37-42
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• 2017

We are designed to control the lipoid variation of the structure system with the stratum corneum on the skin. The skin structure is consisted of a morphology how to use the lipoid component, and the given skin structure is consisted of the mechanical shapes of the intercellular route and transcellular route, and is confirmed to control the variation state of the structure capacity. The skin impedance is appeared to result the value of measurement such as shapes of ${\lambda}-Lip-RSC$, ${\lambda}-Lip-RSL$, ${\lambda}-Lip-CSG$, ${\lambda}-Lip-CSS$ and ${\lambda}-Lip-RSB$. The condition is showed to the alteration difference value of the intercellular route and transcellular route. And, composition condition is established to separate the division parts for conversion system that is constructed with the alteration modeling. We will be possible to progress the improvement effectiveness of the continuous skin control system on the skin.

• Journal of Bio-Environment Control
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• v.10 no.4
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• pp.232-236
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• 2001

Four air temperature levels of 23, 25, 27 and 29$^{\circ}C$, three humidity levels of 85, 90 and 95% R.H. at photosynthetic photon flux (PPF) of 50 $\mu$mol.m$^{-2}$ .s$^{-1}$ were provided to investigate the effect of vapor pressure deficit on the evapotranspiration rate (EVTR) and graft-taking of watermelon grafted seed-increase. Thus EVTR of grafted seedlings increased with increasing air temperature at high humidity of 95%R.H. At relatively low humidity of 85% R.H., grafted seedlings showed a high EVTR and some wilting of scions was observed at this condition. This result would be ascribed to the low supply of water to vascular bundles according to the insufficient joining of scions and rootstocks. Differences in EVTR between 90% R.H. and 95% R.H. were not observed. Grafted seedlings showed high graft-taking at high relative humidity. Relative humidity had highly influenced to the graft-taking as compared to the air temperature. Graft-taking increased with decreasing vapor pressure deficit. Graft-taking greater than 90% was found at vapor pressure deficit less than 0.4kPa which could be obtained at humidity higher than 90% R.H. Therefore it is required to control the humidity higher than 90% R.H. for suppressing EVTR of grafted seedlings and preventing some wilting of scoins and thus enhancing the graft-taking of grafted seedlings.