• Journal of the Institute of Electronics Engineers of Korea SC
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• v.38 no.5
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• pp.33-41
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• 2001

The digital iron using ${\mu}$ processor is designed and compared experimentally with the conventional analog Iron. Designed digital iron shows two improved temperature control characteristics. First, the reduction of the difference error between the user setting temperature and the real temperature of the iron tip is examined. When the iron temperature is set to $200[^{\circ}C]$, $300[^{\circ}C]$, $400[^{\circ}C]$, $480[^{\circ}C]$ at the environmental temperatures of $-5[^{\circ}C]$ and $25[^{\circ}C]$, it is examined that the tip temperature is very stable and its error is within ${\pm}1.8[^{\circ}C]$. Second, it is conformed that the temperature fluctuation of the iron due to the soldering is reduced manifestly. When the temperature of iron tip is varied from $200[^{\circ}C]$ to $480[^{\circ}C]$ with 1[g] solder, the temperature errors of the analog iron are measured to be from $6[^{\circ}C]$ to $10[^{\circ}C]$. In case of designed digital iron, however, these errors are much smaller and they are from $2[^{\circ}C]$ to $5[^{\circ}C]$.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1264_1265
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• 2009

Cadmium Telluride (CdTe)를 이용한 박막형 태양전지 제작과 실용화에 있어 가장 큰 이슈는 대면적화에 따른 에너지 변환효율의 저하를 줄임으로써 고효율의 대면적 태양전지를 대량으로 생산하는 것이다. 따라서 본 연구에서는 태양전지 박막의 대면적 증착시 문제점 중에 하나인 불균일한 CdTe 박막의 증착을 방지하기 위한 선행연구를 진행하였다. 실험 방법으로는 Sputtering 법을 적용하여 박막 증착시 출력과 진공도에 따른 박막 두께의 표준편차와 RMS 표면 거칠기($R_{rms}$), 최고-최저점간 표면 거칠기($R_{p-v}$) 등의 거동을 고찰하였다. 이를 통해 Sputtering 공정 변수 중에 박막 두께의 표준 편차에 더 큰 영향을 미치는 변수를 조사하고, 후행 연구로 진행될 Sputtering 법을 이용하여 대면적에 균일하게 증착하는 방법에 적용하고자 한다.

• Journal of the Korean Chemical Society
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• v.31 no.5
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• pp.425-433
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• 1987

The separation of 19 organochlorine pesticides was studied by capillary column gas chromatography. The applicability of this method to the fresh rice was investigated. Comparison of the resolution of pesticides by OV-17 and SE-30 capillary columns revealed that OV-17 column (25m ${\times}$ 0.20mm, 0.27${\mu}$m thickness) showed better resolution. The relative standard deviations (RSD) for their retention times and peak areas obtained by splitless injection mode were within 0.16% and 8.2%, respectively. The recoveries of pesticides spiked in fresh rice were mostly over 85% and their RSDS did not exceed 11.4%.

• Korean Journal of Optics and Photonics
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• v.7 no.1
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• pp.37-43
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• 1996

Two type interference air refractometers have been developed by using a frequency stabilized He-Ne laser in a transverse magnetic field. The refractometers were based on symmetric multiple pass interferometer. In this system, One part of the beams passed through air whose refractivity is to be measured and the other part of the beams passed through a vacuum champer to be used as a reference. Several measurements were performed under normal air condition. Maximum difference between two interference refractometers was ${\pm}2{\times}10^{-8}$.

• Proceedings of the Safety Management and Science Conference
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• 2013.11a
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• pp.587-595
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• 2013

기계가공으로 인한 사고는 작업자에게 치명적인 경우가 많다. 이러한 사고는 완벽한 가공지그을 통해 대부분 예방이 가능하지만 제품설계초기 후가공과 양산 공정은 고려되지 않고 설계되어 기계가공 시 재해로 연결되는 경우가 빈번히 발생하고 있다. 사형주조법은 수작업으로 손쉽게 제품을 생산하는 장점을 가지는 반면 치수오차가 다른 양산공정 보다 크다는 단점을 가진다. 이런 사형 주조품을 기계 가공할 때 제품의 치수편차로 인해 불안전한 고정및 과다한 절삭, 제품이탈, 공구파손, 장비와 공구의 빠른 수명감소 등의 다양한 문제가 발생 하지만 사형주조의 특성상 개선하기 어려운 문제로 인식되고 있다. 본 연구에서는 원형의 용기형태의 제품을 사형주조 후 기계가공 하는 것을 금형으로 대체하기 위한 셸몰드법을 제시하고 셸몰드로 만든 셸주형으로 주조함으로서 표면조도 평균 $Ra9.94{\mu}m$의 기계가공에 준하는 표면을 구현하였다. 외형의 정밀한 제품을 대량 생산하여 가공공정의 간소화 및 평균 두께 편차를 줄임으로서 제품파손 및 제작 시 발생할 수 있는 안전사고예방에 긍정적인 영향을 주었다. 기계가공전 제품의 치수정밀도를 높여 안전성, 생산성향상, 가공 공정단축, 환경개선 등을 이 가능함을 확인하였다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.08a
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• pp.41-46
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• 2002

본 논문은 냉, 난방 디지털 온도 조절계(SPC 50)의 Etl의 편차 정 동작에 관한 구현장치 제작과 비례 미.적분기가 At 및 비 At기능에서 설정온도를 $100^{\circ}C$를 유지하는데 기인된 전압전류 및 전력데이터 획득의 요인과 비례미적분 정수 및 노 개선점을 연구하였다. 설정온도를 유지하는 온도변화는 At기능에서 $96.7^{\circ}C\sim102^{\circ}C$ 이며, 비At 기능에서는 $97.6^{\circ}C\sim100.2^{\circ}C$이었다. 온도유지 전압변동은 At기능에서 2V~217V이며, 비 At기능에서 20V~217V 이었다. At와 비 At 기능에서 설정온도 $100^{\circ}C$을 유지하는데 온도를 냉각시키는 환풍기가 온. 오프 되는 시간차는 20초 정도 발생하였다. 온도차 및 전압차는 두 기능간에 비례 미. 적분값 설정이 자동 및 수동이냐에 따라서 차이를 보여주었다. 두 기능에서 설정된 온도값 유지에 따른 전압전류의 승압과 하강의 변동된 변환 데이터는 설정된 온도가 성취되어지는 시간차 및 설정값 유지의 특성을 요인으로 한 PID값과 노의 개선점에 길잡이가 된다.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.10
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• pp.2217-2222
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• 2011

In this paper, the relationship of potential and charge distribution in channel for double gate(DG) MOSFET has been derived from Poisson's equation using Gaussian function. The relationship of subthreshold swing and oxide thickness has been investigated according to variables of doping distribution using Gaussian function, i.e. projected range and standard projected deviation, The analytical potential distribution model has been derived from Poisson's equation, and subthreshold swing has been obtained from this model for the change of oxide thickness. The subthreshold swing has been defined as the derivative of gate voltage to drain current and is theoretically minimum of 60 mS/dec, and very important factor in digital application. Those results of this potential model are compared with those of numerical simulation to verify this model. As a result, since potential model presented in this paper is good agreement with numerical model, the relationship of subthreshold swing and oxide thickness have been analyzed according to the shape of doping distribution.

• Composites Research
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• v.20 no.5
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• pp.49-55
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• 2007

Nanocomposite blade for dicing semiconductor wafer is investigated for micro/nano-device and micro/nano-fabrication. While metal blade has been used for dicing of silicon wafer, polymer composite blades are used for machining of quartz wafer in semiconductor and cellular phone industry in these days. Organic-inorganic material selection is important to provide the blade with machinability, electrical conductivity, strength, ductility and wear resistance. Maintaining constant thickness with micro-dimension during shaping is one of the important technologies fer machining micro/nano fabrication. In this study the fabrication of blade by wet processing of mixing conducting nano ceramic powder, abrasive powder phenol resin and polyimide has been investigated using an experimental approach in which the thickness differential as the primary design criterion. The effect of drying conduction and post pressure are investigated. As a result wet processing techniques reveal that reliable results are achievable with improved dimension tolerance.

• The Journal of the Korea Contents Association
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• v.15 no.4
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• pp.1-8
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• 2015

This paper presents a Electrocardiogram(ECG) identification method using adaptive weight based on Least Mean Square Error(LMSE) optimization. With a preprocessing for noise suppression, we extracts the average ECG signal and its standard deviation at every time instant. Then the extracted information is stored in database. ECG identification is achieved by matching an input ECG signal with the information in database. In computing the matching scores, the standard deviation is used. The scores are computed by applying adaptive weights to the values of the input signal over all time instants. The adaptive weight consists of two terms. The first term is the inverse of the standard deviation of an input signal. The second term is the proportional one to the standard deviation between user SAECGs stored in the DB. Experimental results show up to 100% recognition rate for 32 registered people.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.7
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• pp.1725-1731
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• 2013

Recently, as industrial society is developed as high digital information age, image processing is used in a variety of areas. However, image deterioration is still occurred by several noises in the data processing, and different kinds of researches are in progress for noise removal. Therefore, this paper limited the modified median filter by using standard deviation to removes impulse noise. The proposed algorithms divided into noise detection and noise removal, the noise free pixel is maintained, the noise pixel filtered. And it was compared with the existing methods for its objective judgment, using PSNR(peak signal to noise ratio) as standard criteria.