• 한국수소및신에너지학회논문집
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• 제22권3호
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• pp.380-385
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• 2011

$MgH_2$ was synthesized by hydriding chemical vapor deposition (HCVD). In this study, we examined the hydrogen storage property of $MgH_2$ synthesized by HCVD. The results of pressure-composition-temperature (PCT) measurement showed that the HCVDed $MgH_2$ reversibly absorbed hydrogen as much as 6 wt%. Each hydrogenation rate was very greater than the conventional alloy methods. The reason was that the particle size made by HCVD was small as approximately 1 ${\mu}m$. The PCT of $MgH_2$ made by HCVD methode was similar to a commercial $MgH_2$. The ${\Delta}H$ and ${\Delta}S$ value are respectively -76.8 $kJ/mol{\cdot}H_2$ and -137.4 $kJ/mol{\cdot}H_2$. Mg made by HCVD methode was activated easily than commercial Mg. Also the initial reaction rate was faster than that of commercial $MgH_2$. 70% of the total storage were stored during 400s.

• 한국건설관리학회논문집
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• 제1권2호
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• pp.89-97
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• 2000

EVMS(Earned Value Management System)는 공정-공사비가 통합된 관리기준 상에서 단위 관리항목을 중심으로 계획 대비 실적측정을 통해 공정-공사비 실적 치를 측정, 분석, 예측하는 관리체계로서, 발주자 측면에서는 실적기반의 공사비 집행 및 관리를 통해 예산관리의 효율성을 증진시키며, 시공자측면에서는 공정-공사비 통합을 통한 원가 및 기성관리의 효율화 방안으로서 그 효과를 찾을 수 있다. 최근 우리나라에서도 공공 건설사업 효율화 방안의 일환으로 EVMS에 의한 공정-공사비 통합관리를 시도하고 있으나, EVMS에 대한 지식과 운영기반이 취약한 것으로 나타나고 있다. 따라서 본 연구에서는 국내 건설생산체제를 분석하여 EVMS 개념의 도입을 위한 장애요인과 한계성을 규명하고, 국내 건설환경에 적합한 EVMS에 의한 공정-공사비 통합관리 프로세스 모델을 제안하고자 한다. 이 모델은 6가지 하위 프로세스로 구성된다. : 조직구성, 일정계획, 계약금액 편성, 실적관리기준 설정, 경영분석, 변경사항관리.

• 대한기계학회논문집A
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• 제27권5호
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• pp.823-832
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• 2003

To define the causes of cladding degradation which can take place during the operation of nuclear power plants, it is required to develop the new fracture toughness test of spent fuel cladding. The fracture toughness of Zircaloy-4 cladding was estimated using the recently developed KAERI embedded Charpy (KEC) specimen. Axially notched KEC specimens cut directly from unirradiated fuel claddings, were tested in a way similar to the standard toughness test method of a Single Edge Bending (SEB) specimen. The results of KEC fracture toughness test at room temperatures were discussed and compared with those of the previous other studies. In conclusions, even though the KEC fracture toughness test of nuclear fuel claddings was easier and more reliable than those developed earlier, the results from the cladding fracture tests were not the material characteristics but the specific fracture parameters which were deeply related to the specification of claddings. In addition, the phenomenon of a thickness yielding was not observed from the fracture surface. It was closely related to the fact that the plane strain condition of the KEC specimen was changed to the plane stress condition during crack advancing. It was also supported by the fractographic evidence that the formation of ductile dimples at the crack initiation became the similar appearance such as a quasi-cleavage after the sufficient crack advancing.

• 한국토양비료학회지
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• 제20권3호
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• pp.217-221
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• 1987

요소(尿素), DAP, 증화가리(增化加里)를 주재료(主材料)로, 분뇨잔사(糞尿殘渣)와 Zeolzte를 부재료(副材料)로 활용(活用)하여 제조(製造)한 고추전용복비(專用複肥)인 시제품(試製品) I II를 비닐멀칭재배(栽培)로 비효시험(肥效試驗)을 실시(實施)한 결과(結果)는 다음과 같다. 가. 고추의 초장(草長)과 간경(幹徑)은 시제품(試製品)II구(區)가 대조구(對照區) (NPK분시구(分施區))에 비해 좋았다. 나. 고추의 총적과수량(總赤果收量)은 시제품(試製品)II구(區)가 가장 증수(增收) 하였으나 대조구(對照區)에 비해 통계적(統計的)인 유의성(有意性)은 없었다. 다. 개발(開發)된 시제품(試製品)은 비닐멀칭조건에서 고추재배(栽培)를 위한 전량기비용비료(全量基肥用肥料)로서 가능(可能)하였다.

• Tuberculosis and Respiratory Diseases
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• 제51권5호
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• pp.474-481
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• 2001

염증성 장질환 환자에서 폐주변부에 발생하는 진행성 폐침윤과 기침, 발열, 호흡곤란 등의 호흡기계 증상, 말초혈액내 호산구중다중의 발현, 다른 호산구중다중을 유발할 만한 약제나 기생충 감염 등의 원인이 없는 경우에 메살라진이나 설파살라진에 의한 호산구성 폐렴의 가능성율 생각하고, 약제 투여 중단과 스테로이드 사용을 고려해야 하며, 기관지경을 통한 기관지 폐포액에서 호산구 증가와 lymphocyte stimulation test, 폐생검올 통해 진단할 수 있다. 저자들은 궤양성 대장염 환자에서 부작용이 적다고 알려진 메살라진에 의한 호산구성 폐렴 1례를 경험하였기에 문헌 고찰과 함께 보고하는 바이다.

• International Journal of Naval Architecture and Ocean Engineering
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• 제9권5호
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• pp.484-491
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• 2017

Recent research has shown that quadrupole noise has a significant influence on the overall characteristics of flow-induced noise and on the performance of underwater appendages such as sonar domes. However, advanced research generally uses the Ffowcs Williams-Hawkings analogy without considering the quadrupole source to reduce computational cost. In this study, flow-induced noise is predicted by using an LES turbulence model and a developed formulation, called the formulation Q1As method to properly take into account the quadrupole source. The noise around a circular cylinder in an underwater environment is examined for two cases with different velocities. The results from the method are compared to those obtained from the experiments and the permeable FW-H method. The results are in good agreement with the experimental data, with a difference of less than 1 dB, which indicates that the formulation Q1As method is suitable for use in predicting quadrupole noise around underwater appendages.

• 한국광학회지
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• 제20권4호
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• pp.249-254
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• 2009

본 연구에서는 파라핀이 코팅된 Rb원자 증기 셀을 이용하여 $^{87}Rb$ $D_1$전이선의 Hanle스펙트럼과 비선형 광자기 효과 신호를 조사하였다. 파라핀 코팅 증기 셀의 효과에 의한 좁은 스펙트럼 폭을 가진 영역과 순수 증기 셀에서 얻을 수 있는 넓은 스펙트럼폭을 가진 이중구조의 Hanle 스펙트럼을 관측할 수 있었다. 스펙트럼에 나타난 이중구조에서 좁은 선폭 영역의 선폭은 1 kHz로 측정되었고, 스펙트럼 크기는 전체 스펙트럼에 대해서 10%로 측정되었다. 또한, Hanle 스펙트럼에 대응되는 이중 미분형태의 비선형 광자기 신호를 관측하였으며, 기울기가 급격하게 변하는 비선형 광자기 신호의 기울기는 레이저의 출력이 $200{\mu}W$일 때 대략 10 mV/${\mu}T$였다.

• 한국건설순환자원학회논문집
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• 제4권4호
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• pp.470-476
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• 2016

Many studies have been performed on hybrid fiber reinforced concrete for years, which is to improve some of the weak material properties of concrete. Studies on characteristics of hybrid fiber reinforced concrete using amorphous steel fiber and polyamide fiber, however, yet remain to be done. The purpose of this experimental research is to evaluate the workability and mechanical properties of hybrid fiber reinforced concrete using amorphous steel fiber and polyamide fiber. For this purpose, the hybrid fiber reinforced concrete containing amorphous steel fiber(ASF) and polyamide fiber(PAF) were made according to their total volume fraction of 0.5 % for water-binder ratio of 33 %, and then the mechanical properties such as the compressive strength, direct tensile strength, flexural strength, and flexural toughness of those were estimated. It was observed from the test results that the compressive strength was slightly decreased with increasing ASF and decreasing PAF and the effect of fiber combination on the flexural strength was not much but the flexural toughness was relatively largely increased with decreasing ASF and increasing PAF.

• 한국해양공학회지
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• 제20권2호
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• pp.59-65
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• 2006

Steel, as a reinforcing mechanism in concrete, provides the tensile strength that is lacking in concrete, alone, and the high alkaline environment (pH 12.5) in concrete offers satisfactory protection against most corrosion of the steel. However, the corrosion of reinforcing steel in concrete can occur by chloride attack or carbonation, and it can cause a loss of integrity a section and concrete failure through cracking and spalling. In this study, a transient electro magnetic method (TEM) of a nondestructive technique is adapted to study the measuring method of steel corrosion in mortar. The sensor was made of an enameled wire, with a diameter of 0.25mm and anacril. He sensor configuration used was a coincident loop type. The secondary electro motive force (2nd EMF) was measured with SIROTEMIII, which equipped the accelerator. The accelerator allowsthe transmitter to turn off approximately $10\sim15$ times faster than normal. The high-resolution time series, used for very shallow or a high resistivity investigation was selected. After steels were corroded by the salt spray, during 4, 8, 15 and 25 days, they were embedded in mortar. The content results acquired in this study are as follows. The variation of the secondary electro motive force (2nd EMF) was shown by the change of steel surface with different corrosion time steel. It was confirmed that measurement of steel corrosion in mortar by a transient electro-magnetic method (TEM) can be possible.

• Tuberculosis and Respiratory Diseases
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• 제47권6호
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• pp.850-856
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• 1999

저자들은 31세 남자환자에서 고열, 흉막성 흉통 및 흉막 유출액의 임상증상을 보이며 검사상 다발성 혈관염 소견을 보였으며, 결핵성 흉막염 및 불명열로 오인되었던 베체트병을 부신피질 호르몬제 및 colchicine, 비스테로이드성 항염증약물을 이용하여 치료한 1예를 경험하였기에 이에 보고하는 바이다.