• 대한전기학회:학술대회논문집
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• 대한전기학회 1984년도 하계학술회의논문집
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• pp.226-229
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• 1984

A novel high intensity charging device has been developed for the control of the submicron particles, such as the diesel soot particulates, which are very hard to charge highly by any means of the conventional charging device. Having new corona electrodes of a multineedle disk with the corona field-control electrodes in the outer-cylinder electrode, extremely intense and stable coronas on there sharp points expanding both radially and axially are established in the corona charging region between the multi-corona -needles and an outer-cylinder electrode. As a result, the maximum corona field intensity and current density of the charging device of the standard one on soot load in laboratory tests have been 8.5KV/cm(E=$2V_m$/D(1nD/d)) and $6.5{\mu}A/cm^2$ which enhance greatly the charging of soot particles about several 100 times higher than those obtained in conventional cylinder precipitators.

• 대한화장품학회지
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• 제14권1호
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• pp.1-15
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• 1988

A new method for liquid chromatography with post column reaction is suggested for the separation and quantification of tertiary amines. A mixture of triethanolamine and N-ethyl diethanolamine was separated by a strong cation exchange column, followed by spectrophtometric detection of the blue colors generated from the reaction of each amine with the Folin-Ciocalteau reagent. The tertiary amines were properly separated when an eluent of pH 9.5 containing 0.5M sodium nitrate was used. Under this condition, calibration curve of triethanolamine in 2-10mg/100ml concentration range was attained. Good results were obtained when cream and shampoo preparations containing known amount of triethanolamine were analysed according to this method. In case the sample did not contain any other interfering reducing substances, the amine was quantitatively determined by the simple reaction of the samples with Folin-Ciocalteau reagent, and the subsequent spectrophotometric measurement.

• 한국소음진동공학회논문집
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• 제26권5호
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• pp.578-583
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• 2016

In order to provide a basis data for design of small arms and their silencer, an experimental study on firing noise of small arms was performed around the muzzle of a gun. For this experimental comparison analysis, the target small arms were included most operating small arms in our country. The sound pressure levels were measured at a certain distance which was predetermined according to US army firing test procedure, TOP 3-2-045. By this experimental study, the sound pressure levels of 5.56 mm caliber small arms are 143 dB ~ 145.4 dB and 7.62 mm caliber small arms are 144 dB ~ 145.2 dB. Between the heavy machine gun K12 and M60, the sound pressure level of K12 is slightly lower than M60.Also silencer for K14 snifer rifle was tested. Using this result, it has been found that the reduction effect of the silencer is 15.4 dB but the improvements of silencer performance in the high frequency range have to be studied later on.

• Current Optics and Photonics
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• 제3권1호
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• pp.8-15
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• 2019

We describe a common optical system that merges a LADAR system, which generates a point cloud, and a more traditional imaging system operating in the LWIR, which generates image data. The optimum diameter of the entrance pupil was determined by analysis of detection ranges of the LADAR sensor, and the result was applied to design a common optical system using LADAR sensors and LWIR sensors; the performance of these sensors was then evaluated. The minimum detectable signal of the $128{\times}128-pixel$ LADAR detector was calculated as 20.5 nW. The detection range of the LADAR optical system was calculated to be 1,000 m, and according to the results, the optimum diameter of the entrance pupil was determined to be 15.7 cm. The modulation transfer function (MTF) in relation to the diffraction limit of the designed common optical system was analyzed and, according to the results, the MTF of the LADAR optical system was 98.8% at the spatial frequency of 5 cycles per millimeter, while that of the LWIR optical system was 92.4% at the spatial frequency of 29 cycles per millimeter. The detection, recognition, and identification distances of the LWIR optical system were determined to be 5.12, 2.82, and 1.96 km, respectively.

• 대한원격탐사학회지
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• 제18권5호
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• pp.291-297
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• 2002

Optimal allocation of viewers on a terrain in such a wav that the hidden area would be minimized has many practical applications. However, it is impossible in practical sense to evaluate all the possible allocations. In this paper, we propose an optimal allocation of viewers based on genetic algorithm that enables probabilistic search of huge solution space. An experiment for one and three viewers was performed. The algorithm converges to good solutions. Especially, in one viewer case, the algorithm found the best solution.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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• pp.1255-1258
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• 2008

New phosphors that enable the 3D application of PDP have been developed The decay times of $Y_3Al_5O_{12}:Ce^{3+}$, $(Y,Gd)Al_3(BO_3)_4:Tb^{3+}$ and $(Y,Gd)_2O_3:Eu^{3+}$ were extremely shorter than those of conventional PDP phosphors. The color coordinates and intensities of the phosphors were also suitable for PDP For the first time in PDP industry, 3D/2D switchable PDP has been commercially available by adopting the phosphors.

• 한국광학회지
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• 제23권1호
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• pp.6-11
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• 2012

256개의 ONU를 수용하며 50 km 전송거리를 갖는 차세대 시분할 수동광망(TDM-PON) 링크에 링크 확장기로 반도체 광증폭기가 적용되었다. 이 광증폭기의 이득은 25dB 였고 입력신호 변화에 따른 이득 자동조정장치는 사용되지 않았다. 상향 링크의 전체 광세기 범위는 58 dB 였고, 광증폭기로의 입력신호가 -30 dBm인 조건에서 링크의 $10^{-9}$ BER을 위한 수신감도는 -25 dBm였다. 그 입력세기가 -10 dBm인 경우 버스트 신호에 의한 증폭기의 이득 과도응답에 의한 초과펄스왜곡은 45% 였고 이로 인한 신호성능의 악화는 $10^{-12}$ BER 에서 1.55 dB의 페널티를 발생시켰다. 그러나 -15 dBm 이하의 입력조건에서는 페널티는 무시할 수준으로 급격히 낮아져서, 링크의 다이나믹 범위가 최소한 -15 dBm 까지는 보장되었다. 이 같이 측정된 입력신호의 다이나믹 범위는 50 km이상 장거리 그리고 수백개 이상의 다수가입자를 지원하는 차세대 수동광망에서 링크 확장기로 광증폭기가 사용되더라도 광증폭기 이득 자동조정장치를 사용하는 것이 필수적이지 않음을 의미한다.

• Journal of electromagnetic engineering and science
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• 제4권3호
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• pp.137-142
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• 2004

In this paper, we present a new current-current negative feedback(CCNF) differential voltage-controlled oscillator (VCO) with 1/f induced low-frequency noise suppressed. By means of the CCNF, the 1/f induced low-frequency noise is removed from the proposed CCNF VCO. Also, high-frequency noise is stopped from being down-converted into phase noise by means of the increased output impedance through the CCNF and the feedback capacitor $C_f. The proposed CCNF VCO represents 11-dB reduction in phase noise at 10 kHz offset, compared with the conventional differential VCO. The phase noise of the proposed CCNF VCO is measured as - 87 dBc/Hz at 10 kHz offset frequency from 5.5-GHz carrier. The proposed CCNF VCO consumes 14.0 mA at 2.0 V supply voltage, and shows single-ended output power of - 12 dBm.

• 한국전자파학회논문지
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• 제17권11호
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• pp.1096-1104
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• 2006

본 논문에서는 Cellular/PCS/IMT-2000/Wibro 및 S-DMB의 서비스 대역을 모두 만족하는 통합 기지국용 광대역 안테나를 설계하였다. 바이코니컬 종단 부분에 테이퍼 구조를 적용하여 광대역 임피던스 정합을 구현하였으며, 시간영역 유한차분법(FDTD)을 통해 설계 및 시뮬레이션을 수행하였다. 측정 결과, 제작된 안테나는 대역폭 $0.79GHz{\sim}2.93GHz$에서 5.50 dBi 이상 최대 8.19 dBi의 이득 특성을 갖는다.

• 농업과학연구
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• 제25권1호
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• pp.79-88
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• 1998

본 연구는 축협중앙회 한우개량부에서 사육중인 한우의 혈액으로부터 genomic DNA를 추출하여 한우의 면역체계에 중요한 역할을 담당하고 있는 BoLA DRB3 exon2 유전자를 PCR기법을 이용하여 증폭하고 친자확인을 위한 이들 대립유전자들의 염기서열을 분석하여 한우의 효율적인 육종에 분자유전수준에서의 접목을 위한 기초자료를 얻고자 실시하였던바, 얻어진 결과를 요약하면 다음과 같다. 1 한우의 혈액에서 추출된 genomic DNA를 1.5% agarose gel에서 전기영동한 결과, 12.2kb이상의 단일밴드로 나타나, genomic DNA는 아주 잘 분리된 것으로 판단되었으며, 한편 genomic DNA로부터 PCR기법을 이용하여 BoLA DRB3 exon2 유전자를 증폭한 결과 284kb의 단편이 증폭 되었음을 확인하였다. 2. PCR 증폭산물을 pCR 2.1 vector를 사용하여 cloning 하고, 균주에 형질전환을 시켜 재조합 plasmid를 추출한 후, EcoR 1으로 처리한 결과 300bp 단편이 확인되어 증폭되어진 BoLA DRB3 exon2 유전자가 vector 내에 잘 삽입되었음을 확인하였다. 3. 부와 모의 BoLA DRB3 exon2 대립유전자의 염기서열을 분석한 결과 염기서열의 상동성은 부의 대립유전자간에는 82.0% 이었고, 모의 대립유전자간에는 90.1%이었다. 4. 친자를 확인하기 위해 부와 모 그리고 자손간의 가계에 대한 BoLA DRB3 exon2 대립유전자의 염기서열을 분석한 결과 Mendel 의 법칙에 따라 유전된다는 사실을 확인 할 수 있었다. 5. 이상의 결과를 종합하여보면 한우의 BoLA DRB3 exon2 유전자의 부와 모, 그리고 자손의 대립유전자에 대한 염기서열 수준에서의 친자확인이 가능하였으며, 이들 연구결과는 축우의 유전적 능력개량에 중요한 분자유전학적 기초 자료가 될 것으로 판단되었다.