• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.334-334
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• 2013

In the past decade, the infrared detectors based on intersubband transition in quantum dots (QDs) have attracted much attention due to lower dark currents and increased lifetimes, which are in turn due a three-dimensional confinement and a reduction of scattering, respectively. In parallel, focal plane array development for infrared imaging has proceeded from the first to third generations (linear arrays, 2D arrays for staring systems, and large format with enhanced capabilities, respectively). For a step further towards the next generation of FPAs, it is envisioned that a two-dimensional metal hole array (2D-MHA) structures will improve the FPA structure by enhancing the coupling to photodetectors via local field engineering, and will enable wavelength filtering. In regard to the improved performance at certain wavelengths, it is worth pointing out the structural difference between previous 2D-MHA integrated front-illuminated single pixel devices and back-illuminated devices. Apart from the pixel linear dimension, it is a distinct difference that there is a metal cladding (composed of a number of metals for ohmic contact and the read-out integrated circuit hybridization) in the FPA between the heavily doped gallium arsenide used as the contact layer and the ROIC; on the contrary, the front-illuminated single pixel device consists of two heavily doped contact layers separated by the QD-absorber on a semi-infinite GaAs substrate. This paper is focused on analyzing the impact of a two dimensional metal hole array structure integrated to the back-illuminated quantum dots-in-a-well (DWELL) infrared photodetectors. The metal hole array consisting of subwavelength-circular holes penetrating gold layer (2DAu-CHA) provides the enhanced responsivity of DWELL infrared photodetector at certain wavelengths. The performance of 2D-Au-CHA is investigated by calculating the absorption of active layer in the DWELL structure using a finite integration technique. Simulation results show the enhanced electric fields (thereby increasing the absorption in the active layer) resulting from a surface plasmon, a guided mode, and Fabry-Perot resonances. Simulation method accomplished in this paper provides a generalized approach to optimize the design of any type of couplers integrated to infrared photodetectors.

• 대한미생물학회지
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• 제21권1호
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• pp.1-16
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• 1986

Fifty-one strains of Pseudomonas aeruginosa were isolated from various clinical specimens. Among them, 26 (51%) strains were gentamicin-resistant (Gm') and 25 (49%) were susceptible to gentamicin (Gm'). The frequencies of resistant strains to piperacillin (Pi), cefotaxime, moxalactam, cefoperazone (Cz), and amikacin (Ak) ranged from 21.6 to 31.4%, and $MIC_{50}$ of these drugs were lower than the critical concentrations of susceptibility and resistance. Thirty (58.8%) strains were multiply resistant to 12 or more drugs. All Gm' strains were multiply resistant to 12 or more drugs and one was resistant to all 18 drugs tested, while only four Gm' strains were multiply resistant to 12 drugs and the multiplicity of resistance of the other Gm' strains were less than 10 drugs. Resistance to Gm appeared to have a significant correlation with the resistance to tobramycin (Tb), Ak, Pi, and Cz. All Gm' strains were resistant to Tb and about 38.4 to 46.1% of them were resistant to Ak, Pi, and Cz. The incorporation of $Ca^{++}$ and $Mg^{++}$ ions in Mueller-Hinton agar (MHA) did not influence the MICs of Gm, Tb, carbenicillin (Cb), Pi, and Cz as compared with the results obtained in MHA without these ions. Gm strains were studied on the combined effect of beta-lactam antibiotics and aminoglycosides by the methods of checkerboard and modified paper strip diffusion. Most Gm' strains showed significant synergistic effects by the FIC index between Ak and three beta-lactam antibiotics; Cb, Pi, and Cz, but these results did not in agreement the results obtained through the method of modified paper strip diffusion test. In order to know the nature of the drug resistance of P. aernginosa, the plasmid profile analysis was studied. Agarose gel electrophoresis of lysates processed by the method of Kado and Liu showed one or more plasmids in 22 (43.1%) strains. A group of 19 strains showed at least one band of plasmid and three strains two bands. The range of the molecular weight of plasmids was 3.8 to 243 Mdal. All strains carrying large plasmids larger than 200 Mdal were isolated from wound specimens. Three Gm' strains also harboured the plasm ids of 13 to 203 Mdal.

• 한국재난관리표준학회지
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• 제1권2호
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• pp.79-85
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• 2008

본 연구는 지진이 발생한 경우, 교량이 위치하고 있는 기초부 주변토체의 영향을 포함하고 그 위에 위치한 교량시스템의 동적거동을 예측하여 결과적으로 전체적 교량시스템의 내진거동을 분석하기 위한 통합된 새로운 방법론(Unified Dynamic Analysis Method)에 대하여 제안하고자 한다. 주변토체의 영향을 포함한 교량의 내진거동을 분석하는 통합된 방법론은 교량의 내진평가시에 적절하게 사용 될 수 있다는 것을 밝혔다. 본 방법론을 이용시 다중입력파에 대한 영향분석도 용이할 수 있다.

• 한국재난관리표준학회지
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• 제2권2호
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• pp.69-74
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• 2009

본 연구는 대형폐기물 매립장 건설에 따른 매립원지반의 액상화가능성 예측을 통해 폐기물 매립장의 내진 안전성을 평가하고자 한다. 본 연구의 목적을 달성하고자 실내시험 및 지진응답해석결과를 바탕으로 액상화 간편 및 상세 예측법을 사용하여 매립 원지반의 액상화 평가를 수행하였다. 지진응답해석 결과 최대가속도는 0.169 g(BH-14)로 산정되었으며 액상화 간편예측 결과 BH-14를 제외한 대부분 지역은 안전하였다. 액상화 간편 예측법에서 불안전했던 BH-14는 액상화 상세 예측결과 안전율 1.0이상으로 액상화에 안전하다고 판단된다.

• Transactions on Electrical and Electronic Materials
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• 제9권4호
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• pp.163-168
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• 2008

Photonic crystal structures have been received considerable attention due to their high optical sensitivity. One of the techniques to construct their structure is the dip-pen lithography (DPN) process, which requires a nano-scale resolution and high reliability. In this paper, we propose a two dimensional photonic crystal array to improve the sensitivity of optical biosensor and DPN process to realize it. As a result of DPN patterning test, we have observed that the diffusion coefficient of the mercaptohexadecanoic acid (MHA) molecule ink in octanol is much larger than that in acetonitrile. In addition, we have designed and fabricated optical waveguides based on the mach-zehnder interferometer (MZI) for application to biosensors. The waveguides were optimized at a wavelength of 1550 nm and fabricated according to the design rule of 0.45 delta%, which is the difference of refractive index between the core and clad. The MZI optical waveguides were measured of the optical characteristics for the application of biosensor.

• 사료
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• 통권52호
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• pp.48-54
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• 2011

사료기술연구소는 수입사료의 검정과 회원사에서 자가품질검사 등과 관련하여 검정의뢰하는 사료에 대하여 분석 영역별 전문가가 검정하여 결과를 통보해 주고 있으며, 특히 회원사가 자체적으로 분석이 곤란한 성분에 대하여 품질관리를 대행해 주고 있다. 영양성분 중 아미노산은 매우 중요한 관리 항목이며, 따라서 사료관리법 시행규칙 별표8의 자가품질검사기준에서 돼지 및 닭 배합사료의 아미노산 성분은 6개월마다 1회 이상 자체 검사를 하도록 규정되어 있다. 또한 배합사료의 성분등록시 양돈사료에서는 "라이신" 함량을 닭 사료에서는 "메치오닌+시스틴+MHA" 함량을 등록하도록 규정되어 있다. 사료기술연구소는 아미노산 전용분석기 (HITACHI) 2대를 구비하여 사료검정에 운용하고 있으며, 분석결과의 정확도와 정밀도를 높이기 위하여 매월 1회 미국 AAFCO(사료검사관협회) check sample program에 참여하고 있으며 상위의 높은 신뢰도를 유지하고 있다. 본고에서는 아미노산 분석에 대한 이해를 돕고자 실무 분석방법과 당 연구소에서 최근 5년 동안 분석한 원료에 대한 아미노산의 분석 통계치등을 정리하여 품질관리에 참고자료로 활용토록 하고자 자료를 정리하였다. 참고로 지난 5년간 통계량을 보면 연평균 아미노산 분석 건수는 산안정아미노산 1,418건, 함유황아미노산 1,165건으로 총 2,583 건이며 그중 원료사료의 분석결과를 정리하였다. 의뢰 사료중 많은 경우가 원료명이 표기되지 않아 자료로 사용할 수 없었고 일부 원료(육분, 대용유등)는 분석치 변이가 크게 나타나 제외하였다. 아미노산 평균치 자료는 곡류, 강피류, 동물성단백질류 식물성박류, 기타 순으로 정리하였다.

• 한국BIM학회 논문집
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• 제3권4호
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• pp.1-10
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• 2013

In order to boost productivity and efficiency of architectural design, architect accumulates materials and details which are repeatedly used. According as introduction and application of BIM (Building Information Modeling) have proliferated, a number of data are being produced. BIM data constructed in a stage of architectural design reduces repetitive works of design and can be used in estimate and construction, maintenance. BIM library gathered these data are able to enhance participants collaboration and design improvement. Library is a vital factor in BIM and a number of libraries are needed as BIM introduction and application have proliferated in architecture industry. However, BIM Library establishment and related research development are incomplete. And specific standard setting and institutional environment for BIM library building have not been achieved. As such a vast amount of information are generated but there is no systematic plan and reuse frequency is low. So it is necessary to build system for effective data sharing and operation management. In this study, through establishment of BIM standard system and construction of management environmental system, it has an object in view for developing framework which can efficiently manage various libraries happened in BIM architectural design field.

• 한국지진공학회논문집
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• 제9권6호
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• pp.53-58
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• 2005

본 연구에서는 지진하중을 받는 교량의 거동을 확률밀도함수를 통하여 분석할 수 있는 기법을 개발하였다. 확률밀도함수의 전개는 추계론적 이론을 이용한 반해석적 방법을 통하여 구하였으며, 반해석적 방법은 교량운동방정식으로부터 상응하는 Fokker-Planck equation을 구한 후, path-integral solution을 유도하여 이를 수치적으로 해석함으로써 구할 수 있다. 교량거동의 확률밀도 함수전개로부터 교량거동의 확률적 특성을 파악하고 확률밀도함수의 범위로부터 교량응답거동의 포락선을 얻을 수 있으며 이를 이용하여 최대응답의 범위를 결정할 수 있다는 것을 밝혔다.

• 대한의생명과학회지
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• 제18권1호
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• pp.42-48
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• 2012

This study was performed to investigate the urinary methyl hippuric acid (UMHA) excretion among aircraft maintenance workers exposed to xylene by examination of blood test, urine test and biochemical tests. Study subjects (301) were divided into 2 groups; non-exposed group (n=123, who were not exposed to xylene), and exposed group (n=178, who were exposed to xylene). The average of blood level and MHA level was normal. The ${\gamma}$-GTP level was 35.5 IU/L (45.7%) in the exposed group and 27.9 IU/L (44.7%) in the non-exposed (control) group. The proportion of total cholesterol (TG) level higher than 150 mg/dl were 34.3% in the exposed group and 21.1% in the non-exposed group. These results were showed statistically significant difference (${\chi}^2$ = 6.10, P<0.05). Other items showed no statistically significant differences. The results of urine tests were no statistically significant differences in protein, occult blood and glucose level.

• Structural Engineering and Mechanics
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• 제10권6호
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• pp.621-633
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• 2000

Dynamic responses of a bridge system with several simple spans under longitudinal seismic excitations are examined. The bridge system is modeled as the multiple oscillators and each oscillator consists of four degrees-of-freedom system to implement the poundings between the adjacent oscillators and the friction at movable supports. Pounding effects are considered by introducing the impact elements and a bi-linear model is adopted for the friction force. From the parametric studies, the pounding is found to induce complicated seismic responses and to restrain significantly the relative displacements between the adjacent units. The smaller gap size also restricts more strictly the relative displacement. It is found that the relative displacements between the abutment and adjacent pier unit became much larger than the responses between the inner pier units. Consequently, the unseating failure could take a place between the abutment and nearby pier units. It is also found that the relative displacements of an abutment unit to the adjacent pier unit are governed by the pounding at the opposite side abutment.