• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.180.1-180.1
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• 2012

과학기술위성 3호는 우리 은하계의 근적외선 관측, 우주 배경복사 관측 및 지구 지표면의 적외선 영상 획득을 임무로 하는 우주관측용 적외선카메라와 지구 지표면의 적외선 영상 획득을 임무로 하는 지구관측용 적외선카메라 그리고 한반도 지역의 다중 스펙트럼 영상을 획득함으로써 대기관측 및 환경감시의 임무를 가지는 소형분광영상카메라를 장착한 우주 및 지구과학 연구용 위성이다. 2007년 개발을 시작하여 시험인증모델(EQM, Engineering & Qualification Model) 개발과 열구조모델 (STM, Structure and Thermal Model)을 개발 완료하였고, 2012년 하반기에 발사를 앞두고 2010년 비행모델 유닛들이 납품되기 시작하여 위성체 시스템 레벨에서의 조립 및 시험을 진행하고 있다. 본 논문에서는 조립 및 기능시험 완료후 시스템 레벨에서의 진동 시험, 열진공 시험 및 무게특성 시험등 환경시험의 종류, 목적 그리고 검증 결과를 발표하고자 하며, 아울러 발사장에서 수행된 열구조모델에 대한 환경시험 결과를 발표하고자 한다.

• Korean Journal of Materials Research
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• v.6 no.9
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• pp.905-918
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• 1996

초전도 마그네트 구조용 부재로 최근 개발된 오스테나이트계 스테인레스강 JN1 모재, GTA 용접부 및 열처리재에 대한 기계적 성질을 조사하기 위해 실온(293K)에서 극저온(4K)까지의 온도에서 소형펀치(Small Punch)시험을 실시하였다. GTA 용접부의 용융선 근방의 극저온 기계적 성질은 모재와 용접금속에 비해 크게 저하하였다. 4K에서 실험된 용융선 시험편으로 얻어진 하중-변위곡선상에서 부하의 초기 단계에 보통의 서레이션과 다른 pop-in이 관찰되었고, 이때 시험편 표면의 용융선 근처에서 약 0.1-1mm 정도의 크랙이 발생하였다. 열처리재의 기계적 성질은 열처리 시간과 온도의 증가 또는 시험온도의 저하에 따라 크게 저하되었다. 위의 결과에 기초하여 본 연구에서 실시한 소형 시험편을 사용하는 SP 시험법은 극저온에서 JN1 강의 모재와 열처리재뿐 만 아니라 GTA 용접부의 기계적 성질을 평가할 수 있는 유용한 시험법이었다.

• Aerospace Engineering and Technology
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• v.4 no.2
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• pp.199-202
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• 2005

Separation motion of 1:2 downscaled nose fairing is simulated. In comparison with the experimental results, results of analyses on the separation simulation are verified and the characteristics of nose fairing separation are analyzed. The results shows about 5% analysis error.

• Journal of Practical Agriculture & Fisheries Research
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• v.7 no.1
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• pp.97-108
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• 2005

This study was carried out to determine effects of the feeding length of spent mushroom composts from selenium-enriched mushroom (Se-SMC) on muscular selenium deposition in finishing Hanwoo steers. A total of 30 steers were allotted to an experiment with a 3 × 2 factorial arrangement. Treatments were 2 groups of with and without Se-SMC at three different feeding lengths (2, 4, and 6 months) by body weight (BW). And then dry matter intake, body weight gain, Se concentration and/or content in blood and/or muscle were investigated. Dry matter intake was not affected by feeding length and Se-SMC supplementation. As the feeding length was prolonged, initial and final BW was significantly lowered (p<0.01) with no Se-SMC effect. However, total BW gain was significantly increased (p<0.0001) with increasing feeding length with no effect of Se-SMC. Se-SMC supplementation significantly increased Se concentration in whole blood, but there was no effect on feeding length. Se contents in muscles, especially hind-leg, were significantly increased (p<0.05) as the feeding length was increased. However, there was no difference for Se content between four and six months feeding groups of Se-SMC and also hepatic Se content was not affected by feeding length. On the contrast, hepatic Se content for Se-SMC group within each feeding length was significantly increased (p<0.001) compared with no Se-SMC supplementation. In conclusion, our results suggested that optimum feeding length of Se-SMC as a strategy for the production of Se-fortified beef might be approximately 4 months.

• Journal of the Korean Geosynthetics Society
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• v.20 no.2
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• pp.1-11
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• 2021

In this study, a study related to laboratory and pilot test were performed to use an environmental soil stabilizer developed to induce a hardening reaction similar to that of Ordinary Portland Cement (OPC) by using industrial by-products of blast furnace slag and the combustion ash of a circulating fluidized bed boiler as the main material. For this, specimens were prepared using liquid A of sodium silicate and silica sol, and liquid B of an environmental soil stabilizer (or OPC), and laboratory tests were performed to analyze the strength and environmental characteristics. And pilot test was performed on the aging reservoir, field permeability test and electrical resistivity survey were performed in the field to analyze the applicability. As a result of the laboratory test, the homo-gel compressive strength of the chemical injection material using the environmental soil stabilizer as liquid B was about 2.88 to 3.23 times greater than that of OPC. In addition, the elution amount of most heavy metals was lower than that of OPC, and the survival rate in the fish, acute toxicity test was 100%. Therefore, when judged based on the results of the laboratory test, it was analyzed to be superior to OPC in terms of strength and environment. In the results of the pilot test in the aging reservoir, when the environmental soil stabilizer was reinforced with liquid B of the chemical injection material, the coefficient of permeability in the aging reservoir decreased to 1/50 level. In addition, as a result of the electrical resistivity survey, it was analyzed that the electrical resistivity inside the aging reservoir increased as time passed, the saturation zone disappeared, and the overall reinforcement.

• Proceedings of the Korean Information Science Society Conference
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• 2005.11a
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• pp.484-486
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• 2005

수동 시험은 기존의 프로토콜 검증 방법과는 달리 제품이 실제 운용되는 환경에서 입출력의 관찰만을 가지고 제품의 오류를 검출하는 시험이다. 본 논문은 EFSM(Extended Finite State Machine) 모델을 이용하여 homing 기법을 사용하는 수동시험 기법을 제안하고 이를 검증하기 위하여 제안된 수동 시험 기법을 사용하는 OSPF 프로토콜의 오류 검출기를 개발하였다. 개발된 오류 검출기는 Zebra[6]와 시스코 라우터로 구성된 소규모 네트워크에서 Zebra를 이용해 발생시킨 오류 OSPF 패킷을 잘 검출해내었다.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.1525-1527
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• 2011

포항가속기 연구소에서 3.0 GeV의 에너지로 성능향상(PLS-II)를 위하여 선형가속기에 모듈레이터를 증설하였다. 추가 증설을 위하여 사용될 200 MW 인버터 모듈레이터를 설계, 제작, 시험하고자 한다. 모듈레이터에는 Inverter type 고전압 전원장치를 사용하였으며 사양은 펄스 전압 400 kV, 전류 500A, 펄스폭 8us, 반복횟수 30 Hz이며 부하는 80 MW 클라이스트론을 사용하여 시험할 하였다. 본 논문에서는 설계, 제작 및 시험 결과에 대하여 논하고자 한다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.114-114
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• 2010

산불에 노출되는 경우 열충격으로 작용하는 패턴과 특성을 검토하여 가속열화시험에 반영하는 것이 필요하다. 본 연구에서는 산불환경을 모의하여 복합열화시험을 실시하기위해 복합가속열화 챔버를 구축하였다. 온도는 주로 $200^{\circ}C$에서 최대 $1000^{\circ}C$까지 변화를 주면서 예비시험과 본시험 실하였다.

• Korean Journal of Organic Agriculture
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• v.23 no.4
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• pp.797-811
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• 2015

This study was carried out to identify the control effect of entomopathogenic microagent against Spodoptera exigua on organic chinese cabbage. In laboratory condition, insecticidal activity of 4 commercial BT pesticides against S. exigua were lower than 10% against second instar S. exigua. The insecticidal activity of entomopathogenic nematode were 33.3%, 83.3% and 100% at the concentration of $1{\times}10^2$, $3{\times}10^2$, $1{\times}10^3nematodes/ml$, respectively. Mixture of BT and nematode showed growth inhibition against S. exigua larvae. S. exigua nucleopolyhedrovirus (SeNPV) of $10^5PIBs/ml$ showed more than 70% insecticial activity. The yield of SeNPV was increased as in higher initial inoculation concentration of NPV, food supply, and growth temperature increased. In greenhouse experiment, the control value of BT and nematode mixture treatment was higher than BT and nematode treatment alone against S. exigua. In treatment of $10^7PIBs/ml$ of SeNPV, S. exigua was controlled completely. In farm condition, mixture of microbial agent and organic agricultural material showed higher control value against lepidopteran pest including S. exigua than BT single treatment.

• Journal of Energy Engineering
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• v.23 no.3
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• pp.102-115
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• 2014

In the Ulleung basin in the East Sea of Korea, it is assumed that huge amounts of gas hydrate(GH) are buried. In 2010, drilling operation was performed at the 2nd Ulleung Basin Gas Hydrate Drilling Expedition(UBGH2) to designate a site for field production test. In this study, based on the field production test site model reflecting geological properties, GH dissociation flow interpretation is analyzed and sensitivity analysis is performed to gain understanding of production behavior properties following bottomhole pressure(BHP) variation by using the numerical simulation. The results of this study provide a basis for the preliminary analysis of field production test site.