• Journal of the Korean Vacuum Society
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• v.11 no.2
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• pp.127-134
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• 2002

Recently, Plasma display panel(PDP) has been in the spotlight as one of the next generation flat-panel-display device. The luminance and luminous efficiency improvement is the hot issues for making a plasma display into a large flat panel device. In this paper, We suggest a new penning gas mixture, in order to find the optimum mixture gas in plasma display panel. The optimum gas composition has been found by the partial pressure of inert gases(such as Af and Kr added to matrix of He(70%)-Ne(27%)Xe(3%) and Ne(96%)-Xe(4%)). The influences of Ar or Kr addition to Ne(96%)-Xe(4%) and He(70%)-Ne(27%)-Xe(3%) mixture gases are experimentally investigated for AC Plasma Display Panel. When rare As(0.01%-0.03%) or Kr(0.01%-0.03%) is added Ne-Xe and He-Ne-Xe mixture gases, the luminance increases over 10%-20% and luminous efficiency increases over 10%-20% at 200 Torr. It is sure that luminance and efficiency are improved by Penning effect. Also, This influence of Penning effect is shown by increased wall charge(10%-25%). In addition to the result, firing voltage and minimum sustain voltage was approximately decreased by 2V-3V.

• Korean Journal of Agricultural Science
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• v.17 no.1
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• pp.52-64
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• 1990

As a search for natural antioxidants, antioxdative fractions in Pueraria roots were extracted, identified using column chromatography, thin layer chromatography or high performance liquid chromatography. The components which have most effective antioxidative activities were further identified by IR and GC-MS. Separated antioxidative components were then added to four different oils to examine their antioxidative activities. Yield of extract obtained from pueraria root powder by solvent extraction using four step solvent systems was 2.54%. Antioxidative activity of the extracts was as effective as that of 100 ppm ${\delta}$-tocopherol addition, when 0.1% of the extracts was added to linoleic acid. The strongest antioxidative component of methanol extract of pueraria root was identified as puerarin. Aunioxidative activity of puerarin on lard was more effective than ${\alpha}$-tocopherol, but less effective than ${\delta}$-tocopherol. When the puerarin was added to edible oil and heat treated at $145^{\circ}C$, the acid value was lowest in lard and was highest in soybean oil. Antioxidative activity in terms of carbonyl value, thiobarbituric acid value and anisidine value was most high in palm oil and least in soybean and cottonseed oil.

• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.6
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• pp.153-160
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• 2020

Columns are one of the most critical parts of a structural system subjected to earthquake excitations. In this regard, extensive experimental studies have been conducted to evaluate the effect of fiber reinforced polymer (FRP) wrapping on the seismic performance of reinforced concrete (RC) columns. Among them, many studies focused on the behavior of circular or square RC columns strengthened with CFRP or GFRP sheets. Since the cross-sectional shape affects confinement by FRP wrapping, its strengthening effect and final damage pattern may differ with shapes. In this study, a series of cyclic tests was conducted to investigate the seismic behavior of rectangular reinforced concrete columns strengthened with basalt-based fiber reinforced polymer (BFRP) sheets and composite fiber panels. The result shows that the effect of strengthening is not significant, and it implies a little increase of confinement by BFRP sheets and composite fiber panels, which is considered partly due to the cross-sectional shape of the columns.

• Journal of the Korea institute for structural maintenance and inspection
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• v.26 no.6
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• pp.256-262
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• 2022

The purpose of this study is to define the shear reinforcing effect of Near-Surface-Mounted (NSM) FRP strips in reinforced concrete (RC) member through a test. Three T shaped RC beams were made and two of them were strengthened with NSM FRP strips for increase shear strength. And those were tested to find the shear strengthening effect. In the test, two case of shear strengthening methods were considered such as 1) with NSM FRP strips having full embedded length and 2) with NSM FRP strips having some what short embedded length and additional externally bonded FRP sheet. As a result, the shear strengthening effect could be obtained when the NSM FRP strips are embedded to have full length up to the bottom of slab. However the shear strength was not increased in the case of having somewhat short embedded length of NSM FRP strips even additional EB sheet was enhanced.

• Bulletin of the Society of Naval Architects of Korea
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• v.32 no.5
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• pp.19-26
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• 1995

표면효과익선(WIG : Wing-In-Ground Effect Ship)은 해면 위를 낮게 비행함으로써 표면효과에 의한 양력 증가를 얻게 되어 초고속으로 운행할 수 있는 선박과 항공기의 중간형태의 차세대 해상운송 수단이다. 해면 위에 직접 이.착륙이 가능하기 때문에 별도의 활주로가 필요 없으며 수륙양용으로 사용 가능하다. 연근해 도서지방 관광 및 신선도 유지가 필수적인 신속화물의 수 송에도 사용될 수 있으며 해난사고 구난 및 해양 경비용으로도 사용가능한 해상 운송수단이다. 본 고에서는 표면효과익선의 특징을 간략히 살펴보고 21세기 고속해상운송수단으로 사용될 가 능성에 대한 경제성 검토 및 핵심애로기술을 살펴보았으며 러시아 표면효과익선의 발달과정과 개발된 선종의 특징을 조사하였다.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.04a
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• pp.137.1-137
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• 2003

본 연구는 저장 중 부패된 복숭아(‘황도’)에서 Botrytis cinerea를 분리한 후 $25^{\circ}C$에서 배양 중 고농도 탄산가스 (35, 60, 100% + 24, 48, 72시간) 환경에서의 생장억제 효과를 구명하고 이에 따른 과실의 품질 변화를 고찰하였다. 실시한 모든 처리 농도에서 곰팡이 생장이 억제되었으며, 가스 농도 및 처리 시간의 증가에 의해 효과가 극대화되었다. 특히, 100% 탄산가스를 24, 48, 72시간 처리할 경우 5일 배양 후 곰팡이의 생장 정도는 무처리구에 비해 각각 25, 39, 46% 감소되었다. 고농도 탄산가스 처리 기간 동안 곰팡이 성장은 억제되었고 가스 환경이 제거될 경우 정상적인 생장을 재개하는 양상을 보였다. 수확된 ‘황도’ 과실을 대상으로 가스처리 효과를 검증한 결과 100% + 24, 48시간, 60% + 48시간 처리가 부패억제에 효과적인 것으로 나타났다. 35% 농도의 경우 효과가 미미하였다. 가스 처리에 따른 과실의 당도 변화는 없었으며 100% + 48시간 처리의 경우 경도가 높게 유지되었다.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.102-102
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• 2011

다목적 댐이 사회경제적으로 많은 편익을 제공함에도 불구하고 댐에 대한 부정적인 여론이 만연하면서 댐의 사회경제적 편익에 대해서는 상대적으로 등한시 되어 왔다. 이러한 이유중 하나는 댐 운영으로 인해 발생되는 사회경제적 효과에 대한 정량적 분석이 어렵기 때문이다. 다목적 댐 운영으로 인해 발생하는 중요한 효과는 잉여 수자원을 활용하여 사계절을 안정적으로 생활용수 및 공업용수를 공급할 수 있다는 것이다. 또한 최근 환경과 생태계에 대한 국민적 관심이 증가하면서 하천유지용수와 환경개선용수 등 다양한 용수의 수원으로서 댐의 역할이 증가하고 있다. 이외에도 댐 운영을 통해 얻어지는 수력발전은 온실효과 저감에 기여하고 있다. 본 연구는 다목적 댐 운영으로 발생하는 용수공급 및 용수활용의 경제적 가치를 추정하여 다목적 댐의 사회경제적 기여효과를 정량적으로 제시하였다.

• Proceedings of the Korean Society of Computer Information Conference
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• 2016.01a
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• pp.233-234
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• 2016

본 논문에서는 컴퓨터 디스플레이를 이용한 입체 전광판 효과에 대해서 나타낸다. 기존 전광판은 하드웨어로 LED를 이용하여 실내 및 옥외 설치되어 광고 및 홍보 효과를 나타내고 있다. 본 연구에서는 LED 전광판의 한계라고 할 수 있는 점광원으로서의 확산광의 효과가 미약한 것을 소프트웨어를 이용하여 해결하고, 설치비용 및 광고 내용 수정 등 설치 이후에 변경이 손쉽지 않는 것들을 소프트웨어를 이용하여 컴퓨터 디스플레이 함으로써 다양한 컬러, 다양한 텍스트, 다양한 동영상을 손쉽게 제작하고, 홍보 할 수 있다. 따라서 실내 LED 효과에 비해서 컴퓨터 디스플레이를 이용한 입체 전광판의 제작 및 내용 변경에 유지 관리가 매우 효과적임을 나타낸다.

• Korean Journal of Construction Engineering and Management
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• v.7 no.4 s.32
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• pp.69-77
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• 2006

In recent years, there has been more reconstruction and redevelopment of apartments rather than efforts to consider alternative to extend the life time of the apartments. It is essential to try to develop ways to adequately maintain and to use the apartment facilities efficiently in order to preserve earth environment and the limited resource. However, tacking research on the effects obtained through remodelling and maintenance have interfered with the vitalizing of the market. The objective of this study is to propose criterions and methods with which to evaluate adequacy of maintenance management. A survey was performed to investigate important maintenance methods in order to obtain advices that can smoothly progress improve apartment maintenance management. This study applied AHP(Analytical Hierarchy Process) methods for reasonable maintenance in apartment. Through this study, the flow of apartment maintenance market is elevated to reaching the level in advanced nation.

• Journal of the Korea institute for structural maintenance and inspection
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• v.15 no.1
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• pp.226-234
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• 2011

The service life of concrete structures exposed to a marine environment can be extended by controlling the amount of chloride in cover concrete. Patching is one of the appropriate maintenance techniques for chloride contamination. Chloride-contaminated cover concrete is removed and replaced with sound one. It can provide less risk of corrosion of steel, so that the structure can be maintained for required service life. In this study, a quantitative assessment of the service life subjected to the chloride attack is proposed to determine the effective repair options such as repair depth, repair material and timing of repair. The Crank-Nicolson based finite difference formulation from Fick's second law is proposed to predict the profiles of chloride ion in a repaired concrete structure, considering ingress of chloride from outer and redistribution of residual chloride from the substrate concrete. Therefore, the repair application times and maintenance cost for the target service life can be estimated. Finally, the numerical examples are presented to ensure its applicability.