• Proceedings of the KIEE Conference
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• 2002.11b
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• pp.183-185
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• 2002

본 논문에서는 안정적인 변전소의 운영을 위해 최근 개발된 WEB 기반의 초고압 변전설비 원격감시 및 진단 시스템을 소개한다 WEB 기반의 초고압 변전설비 원격 감시 및 진단 시스템은 154kV급 이상의 초고압 변전소에 설치되어 있는 주변압기(MTR)와 가스절연개폐기(GIS)에 대한 감시 및 진단 데이터를 취득하는 Local System과 이러한 데이터를 전송 받아 감시 및 진단 기능과 WEB 서비스를 수행하는 Main Control Center로 구분된다. 실적용 사례로 최근 산업체의 몇 개 공장을 대상으로 시범 적응한 154kV급 변전소의 WEB 기반 감시 및 진단 시스템을 소개한다. 나아가 변전기기를 제어하기 위한 시스템과의 연계 방법에 대해 언급하고 있다.

• Proceedings of the KIEE Conference
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• 2005.07e
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• pp.58-60
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• 2005

초고압 선로에 대한 풍부한 진단 경험과 축적된 Know-how를 바탕으로 선로의 이상유무를 원격으로 진단, 감시하는 On-line PD Monitoring System을 개발하였다. 초고압 선로의 이상 유무를 활선상태에서 정밀하게 진단할 수 있는 전기적인 측정방법으로 부분방전이 유일하다. 그러나 부분방전 신호는 미약하고 주위 노이즈와 구분이 어렵기 때문에 측정 뿐만 아니라 분석하기가 어렵다. 부분방전 측정 장비는 이러한 노이즈를 효과적으로 제거하고 측정된 신호를 의미있는 정보로 가공하여 사용자에게 제공해 주어야 한다. 본 논문에서는 이러한 조건들을 충족하는 고성능의 원격 진단시스템에 관하여 서술하였다.

• Proceedings of the KIEE Conference
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• 2005.07c
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• pp.1968-1970
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• 2005

송전 용량 증대 및 초고압 케이블 컴펙트화를 위해, 최근 고내력 케이블에 관한 연구가 전세계적으로 활발히 진행되고 있으며, 이러한 추세에 대응코자 당사에서는 고내력 케이블 개발에 있어서 첨가제 투입에 따른 절연 능력 향상에 관한 연구를 진행하여왔다. 본 연구에서는 케이블 절연 능력 향상을 위하여 반도전 컴파운드에 첨가제를 투입하여 반도전과 절연의 계면 특성을 향상시킴으로 절연체의 절연파괴능력 향상시키고자 하였으며, 계면 특성의 향상은 절연 파괴능력 향상으로 이어짐을 확인 할 수 있었다. 또한 상기의 연구결과에 따라 제조된 케이블은 기존 케이블과 비교하였을 때 매우 우수한 절연파괴 특성을 나타냄을 확인하였으며, 그 결과 절연 두께를 비약적으로 감소시킬 수 있었다. 본 논문은 상기 절연 성능 향상에 관한 메커니즘 및 IEC 62067에 따라 진행된 초고압 XLPE 케이블의 type test 결과를 중심으로 기술하였다.

• Food Engineering Progress
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• v.15 no.3
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• pp.203-208
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• 2011

Effects of particle size and high pressure processing on the extraction rate of oil compounds from soybean powder were evaluated by Soxhlet method using hexane and supercritical fluid extraction (SFE) using $CO_{2}$. SFE was carried out at 4,000 psi and $50^{\circ}C$ for 4 hr. The mean particle sizes were varied from 26.7 to 862.0 ${\mu}m$ by controlling milling time. Saturation solubility increased as the particle size decreased. At large particle size, high pressure processing (HPP) showed higher extraction yield in both hexane extraction and SFE, but, as the particle size decreased, the HPP was irrelevant to the extraction yield in SFE. The higher extraction rate obtained from the smaller particle size. The scanning electronic microscopy of soybean powder treated by HPP showed pores on the surface of the particle. The higher extraction rate and yield from HPP treatment might be due to the less internal resistance of transferring the solvent and miscellar in the solid matrix by collapsing of tissues.

• Journal of ILASS-Korea
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• v.8 no.1
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• pp.29-36
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• 2003

Spray characteristics on diesel- water emulsion are analyzed in high pressure injection for several variables such as water content, injection pressure. Spray Patterns were visualized under various water content and injection pressures. Spray tip penetration was increased and spray angle decreased in accordance with increasing of water content. But these characteristics were enhanced with increase of injection pressure to high pressure.

• 전기의세계
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• v.24 no.2
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• pp.40-41
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• 1975

필자는 한전자체내의 초고압건설에 관한 해외기술훈련계획에 의거 1974년 6원 12일부터 약 4주간 자유중국 진만전력공사의 345KV 송변전설비건설현장을 견학할 기회가 있어서 체류기간중에 필자가 보고 느낀 초고압건설의 일면을 한국전력의 경우와 비교하여 소개하기로 한다.

• 전기의세계
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• v.26 no.1
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• pp.36-44
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• 1977

본고에서는 (1) 대전력장거리송전계통의 안정도향상 문제, (2) 기간송전계통의 단락전력압제 문제, (3) 대전력장거리송전계통의 계통전압과 주파수의 유지 문제, (4) 사고파급에 의한 광범위대정전의 방지 문제의 문제들에 대하여 초고압계통의 운용에 경험이 있는 외국의 전력계통운용방안들을 참고로하여 그의 개요를 기술코자 한다.

• Korean Journal of Food Science and Technology
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• v.30 no.3
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• pp.602-607
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• 1998

Changes in microbial count, enzyme, texture and color during storage of dongchimi (pickled radish roots) were investigated. Dongchimi was pressurized at 400 MPa for 5 min. Pressurized dongchimi stored at $4^{\circ}C\;(PS4)\;and\;37^{\circ}C\;(PS37)$ were compared with control $(stored\;at\;4^{\circ}C)$. PS4 and PS37 maintained their initial pH values during storage. Lactic acid bacteria, yeast and mold were not detected during storage in pressurized dongchimi. Pectinesterase, polygalacturonase activities and hardness of pressurized dongchimi decreased during storage. PS4 maintained its hardness longer than both control and PS37 during storage. The yellowness of PS37 was too high compared to control and PS4, indicating that storage of pressurized dongchimi at $37^{\circ}C$ was undesirable.

• Korean journal of food and cookery science
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• v.29 no.4
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• pp.387-398
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• 2013

Seasoned soy sauce is one of the popular seasoning sauces added to the Korean traditional foods such as Bulgogi, Galbi. However, industrially processed sauces have poor sensory quality because of heating treatment for sterilization. The purpose of this study was to develop seasoned soy sauce having fresh taste and good quality by applying superheated steam (SHS) and high hydrostatic pressure (HHP) technologies. To maintenance the sauce qualities, food materials such as apple, onion, and garlic were pretreated with SHS (heater $100^{\circ}C$, steam $280^{\circ}C$, 30 s~1 min 30 s) before mixing with other ingredients. During storage of 7 days, color, pH, and browning potential of SHS treated samples (apple, onion and garlic) did not change and also polyphenol oxidase was inactivated (p<0.05). The seasoned soy sauce including SHS treated materials was sterilized by thermal process ($85^{\circ}C$, 30min) or non-thermal process, HHP (550 MPa, $5{\sim}10^{\circ}C$, 3 min). In SHS+HHP treated sauce, salinity, sugar contents, lightness, viscosity did not change (p<0.05), and total viable cell counts were detected below 4 log cycle at $5^{\circ}C$ for 30 days. E.coli and B.cereus are not determined in all samples. In sensory evaluation, Bulgogi prepared with SHS+HHP treated sauce was more acceptable than others.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.10
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• pp.1449-1455
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• 2006

Raw oysters were treated at $10^{\circ}C$ and $22^{\circ}C/350$ Mpa/15 min, and microbial counts and quality were measured during storage of 14 days at $10^{\circ}C$. Total viable cell count (TVCC) in untreated oyster increased greatly during storage from starting inoculum of $1.6\times10^2\;CFU/mL$, and reached to $5.6\times10^2\;CFU/mL$ after 4 days of storage. TVCC of the pressure-treated was about $10^1\;CFU/mL$ right after high hydrostatic pressure treatment and increased slowly during storage, and about $10^3\;CFU/mL$ even after 7 days of storage. Lactic acid bacteria count (LABC) in the untreated was increased greatly during storage from starting inoculum of $3.3\times10^3\;CFU/mL$ at 3 days of storage and $7.2\times10^4\;CFU/mL$ after 4 days of storage. LABC in the pressure-treated was detected only after 5 days of storage, and about $10^2\;CFU/mL$ after 8 days of storage. The pH of the untreated was 6.19 and decreased gradually during storage, and 5.83 after 4 days of storage. The pH of the pressure-treated showed little change during storage, and 6.07, 6.03 and 5.82 after storage of 4, 8 and 14 days, respectively. Volatile basic nitrogen (VBN) in the untreated was 16.8 mg%, and maintained almost constant until 1 day of storage, and then increased suddenly, and 30.1 mg% after 4 days of storage. VBN of the pressure-treated stayed unchanged during storage, and about 20 and 23 mg% even after 4 and 8 days of storage, respectively. Hunter $L^*,\;a^*\;and\;b^*$ values were increased until 2 days of storage and then showed no change during storage. Demerit score was the lowest in the thawed raw oyster, and then in the increasing order of the pressure-treated (4 day and 8 day storage) and the untreated (4 day storage).