• 한국식품과학회지
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• 제32권6호
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• pp.1213-1220
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• 2000

가열산화된 유지의 산패도와 돌연변이원성과의 관련성을 알아보고자 대두유를 $180{\pm}3^{\circ}C$에서 48시간 동안 가열산화시키면서 0, 8, 16, 24, 32, 40, 48시간 후의 유지시료와 여기서 분획한 산화물 및 비산화물을 대상으로 Salmonella typimurium 변이균주 중 구조이동형(frame shift) 변이균주인 TA98, TA1537과 염기치환형(base-pair substituent) 변이균주인 TA100, TA1535 및 TA102를 사용하여 Ames test를 수행한 결과는 다음과 같다. $180{\pm}3^{\circ}C$에서 48시간 가열산화된 대두유의 가열시간에 따른 돌연변이원성을 조사했을 때 직접법 [-S9] 및 대사활성화법 [+S9] 모두에서 돌연변이원성이 인정되지 않았다. 또한 $180{\pm}3^{\circ}C$에서 가열산화된 대두유를 산화물 및 비산화물로 분리하여 돌연변이원성을 조사한 결과 가열 16시간 및 24시간 후의 산화 물질에서 돌연변이 활성이 나타났다.

• 대한기계학회논문집A
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• 제31권10호
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• pp.981-985
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• 2007

We present a MEMS-based portable Direct Methanol Fuel Cell (micro-DFMC), featured by a platinum sputtered microcolumn electrode and a built-in fuel chamber containing a limited amount of methanol fuel. Also presented is a micro-DMFC stack structure having a common electrolyte sandwiched by the microcolumn electrodes. The single cells with ME16 and PE16 electrodes show the maximum power densities of $31.04{\pm}0.29{\mu}W/cm^2$ and $9.75{\pm}0.29{\mu}W/cm^2$, respectively; thus indicating the microcolumn electrode (ME16) generates the power density (3.2 times) higher than the planar electrode (PE16). The single cell tests of ME16 and ME4 electrodes (Fig.8) show the maximum power of $31.04{\pm}0.29{\mu}W/cm^2$, and $25.23{\pm}2.7{\mu}W/cm^2$, respectively; thus demonstrating the increased window frame reduces the normalized standard power deviation (standard deviation over the average power). The normalized deviation of 0.11 in ME4 cell has been reduced to 0.01 in ME16 cell due to the increased window frames. The maximum power density of 4-cell stack is 15.7 times higher than that of the single cell. 4-cell stack produces the power capacity of 20.3mWh/g during 980min operation at the voltage of 450mV with the load resistance of $800{\Omega}$.

• 한국멀티미디어학회논문지
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• 제16권8호
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• pp.927-933
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• 2013

OpenCV (Open Computer Vision)에서 제공하는 얼굴 인식 알고리즘에서는 Haar 특징(Haar feature)들과 대상 영상의 정합 과정인 Haar 매칭 (Haar Matching)을 통하여 얼굴을 검출하는데, 이때 Haar 특징들은 정면 얼굴로 구성된 훈련 영상을 통해 학습된다. 따라서 OpenCV의 얼굴 검출 방법은 정면 얼굴에 대해서는 높은 얼굴 검출율을 보이지만, 정면을 응시하지 않거나 얼굴의 형태가 변형된 경우에는 얼굴을 정확하게 검출하지 못하는 경우가 빈번히 발생한다. 본 논문에서는 측면 얼굴 혹은 형태가 변형된 얼굴에서도 컬러 히스토그램의 분포 특성은 유사하다고 가정하고, 히스토그램 패턴 매칭(histogram pattern matching)을 이용한 얼굴 검출 방법을 제안한다. 제안한 방법에서는 Haar 매칭 오류가 발생한 프레임에 대하여, 정확하게 검출된 이전 프레임의 얼굴 영역에 대한 히스토그램 패턴 매칭을 통하여 가장 유사한 히스토그램 분포를 갖는 영역을 얼굴로 인식한다. 제안한 방법의 얼굴 검출 알고리즘의 성능을 평가하기 위한 모의실험에서 제안한 얼굴 검출 방법이 OpenCV보다 얼굴 검출율이 8% 정도 향상됨을 확인하였다.

• Structural Engineering and Mechanics
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• 제33권3호
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• pp.261-284
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• 2009

The seismic behavior of a framed structure with chevron-type buckling restrained braces was investigated and their behavior factors, such as overstrength, ductility, and response modification factors, were evaluated. Two types of structures, building frame systems and dual systems, with 4, 8, 12, and 16 stories were designed per the IBC 2003, the AISC LRFD and the AISC Seismic Provisions. Nonlinear static pushover analyses using two different loading patterns and incremental dynamic analysis using 20 earthquake records were carried out to compute behavior factors. Time history analyses were also conducted with another 20 earthquakes to obtain dynamic responses. According to the analysis results, the response modification factors turned out to be larger than what is proposed in the provision in low-rise structures, and a little smaller than the code-values in the medium-rise structures. The dual systems, even though designed with smaller seismic load, showed superior static and dynamic performances.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2005년도 춘계 학술발표회 논문집
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• pp.97-104
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• 2005

The seismic behavior of framed structure with Chevron-type bucking restrained braces were investigated and their behavior factors were evaluated following the procedure proposed in ATC-19 & ATC-34. Two types of structures, building frame systems and dual systems, with 4, 8, 12, and 16 stories were designed per the IBC 2000, the AISC LRFD and the AISC/SEAOC Recommended Provisions for BRBF. Nonlinear static pushover analyses were carried out to observe the plastic hinge formation and to identify the loads and the displacements at the yield and the ultimate states. Time history analyses were also carried out to compute the permanent displacement md the dissipated hysteretic energy. According to the analysis results, the response modification factors of model structures fumed out to be larger than what is proposed in the provision in low story structures, and a little smaller in medium-story structures. The dual systems, even though designed with smaller seismic load, showed superior static and dynamic performances.

• 대한전자공학회논문지
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• 제23권1호
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• pp.101-113
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• 1986

In this paper, a real-time pitch detector LPC vocoder as implemented on a high speed digital signal processor, NEC 7720, is described. The pitch detector was based mainly on the SIFT algorithm. The SIFT pitch detector consists primarily of a digital low pass filter, inverse filter, computation of autocorrelation, a peak picker, interpolation, V/UV defcision and a final pitch smoother. In our approach, modification, mainly on the V/UV decision and a final pitch smoother, was made to estimate more accurate pitches. An 16-bit fixed-point aithmatic was employed for all necessary computation and the simulated results were compared with the eye detected pitches obtained from real speech data. The pitch detector occupies 98.8% of the instruction ROM, 37% of the data ROM, and 94% of internal RAM and takes 15.2ms to estimate a pitch when an analysis frame is consisted of 128 sampled speech data. It is observed that the tested results were well agreed with the computer simulation results.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2016년도 추계 학술논문 발표대회
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• pp.17-18
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• 2016

On apartment construction sites in hot weather environments, the high temperature of 30℃ and above and radiation from the sun cause iron and mold temperatures to rise, which lowers worker efficiency and has a negative effect on the deposited concrete. Therefore this study measured the temperature of D10 ~ D16 iron and aluminum items actually used on box frame apartment construction sites currently under construction, in order to give reference information to solve hot weather concrete problems. The temperature measurement results showed that for iron, temperatures rose to around 45℃, and for mold around 58.8℃, calling for safety measures for workers in case of possible burning and other problems.

• 전자공학회논문지C
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• 제34C권8호
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• pp.71-78
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• 1997

An LPC cepstrum processor for speech recognition is implemented on CMOS array process. The designed processor contains a 24-bit floating-point MAC unit to perform the correlation quickly, which occupies the majority of operations used in the algorithm, and has 22 register files to store temporary variables. For the purpose of fast operations, the floating-point MAC consists of a 3-stage pipeline and the new post-normalization shceme is proposed and applied to it. Experimental result shows that it takes approximately 266.mu.s to process 200 samples/frame at 15 MHz clock rate. This processor runs at the maximum rate of 16.6 MHz and the number of gates are 27,760.

• Steel and Composite Structures
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• 제16권2호
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• pp.221-231
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• 2014

The purpose of this study was to evaluate the cyclic behavior of steel column-tree moment connections used in steel moment resisting frames. These connections are composed of shop-welded stub beam-to-column connection and field bolted beam-to-beam splice. In this study, the effects of beam splice length on the seismic performance of column-tree connections were experimentally investigated. The change of the beam splice location alters the bending moment and shear force at the splice, and this may affect the seismic performance of column-tree connections. Three full-scale test specimens of column-tree connections with the splice lengths of 900 mm, 1,100 mm, and 1,300 mm were fabricated and tested. The splice lengths were roughly 1/6, 1/7, 1/8 of the beam span length of 7,500 mm, respectively. The test results showed that all the specimens successfully developed ductile behavior without brittle fracture until 5% radians story drift angle. The maximum moment resisting capacity of the specimens showed little differences. The specimen with the splice length of 1,300 mm showed better bolt slip resistance than the other specimens due to the smallest bending moment at the beam splice.

• Journal of Microbiology and Biotechnology
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• 제8권2호
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• pp.146-151
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• 1998

The aminoglycoside multiple-resistance determinant from Streptoalloteichus hindustanus was cloned into Streptomyces lividans and named nbrB. The 1.2-kb ApaI- BclI fragment encompassing nbrB was located within a 2.6-kb ApaI fragment by successive subcloning experiments. The complete DNA nucleotide sequence of 1.2-kb containing nbrB was determined. The sequence contains an open reading frame that putatively encodes a polypeptide of 281 amino acids with a predicted molecular weight of 30,992. The deduced amino acid sequence of nbrB shows identities of 85.1% to kgmB of S. tenebrarius, 59.6% to sgm of Micromonospora zionensis, and 57.7% to grm of M. rosea. The similarity of nbrB to kgmB suggests that nbrB encodes a 16S rRNA methylase similar to that encoded by kgmB and that both genes might be derived from a common ancestral gene.