• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2002년도 춘계학술대회 논문집
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• pp.3-7
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• 2002

The die casting process was used to manufacture a alternator housing for automobile. Specially automobile parts were required light and hight strength. Therefore simulation have been carried out die casting process of the alternator housing. In this paper, we investigated about characteristics of the die casted alternator housing the HPDC(High Pressure Die Casting) process. Also we designed the die casting die with the simulation results of the alternator housing. The MAGMAsoft and Auto-CAD was used as computer simulation and design code and used material was ADC12(Aluminum Die Casting Alloy). We present the results of filling behavior and design of die process of the alternator housing cast. The result obtained about filling behavior and design of die of the cast showed good agreement with test result.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 춘계학술대회 논문집
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• pp.769-773
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• 2002

The die easting process was used to manufacture a motor housing for automobile. Specially automobile parts were required light and high strength. Therefore simulations have been carried out die casting process of motor housing. In this paper, we investigated about characteristics of the die casted motor housing with HPDC(High Pressure Die Casting) process. Also the MAGMAsoft was used as computer simulation code and used material was ADC12(Aluminum Die Casting Alloy). We present the results of filling behavior and solidification process of a motor housing cast. The analysis results obtained about filling behavior and solidification of cast showed good agreement with test results.

• Journal of Microbiology and Biotechnology
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• 제4권1호
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• pp.7-12
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• 1994

A yeast strain secreting glucoamylase was transformed with an expression vector (pMS12) containing the promoter of yeast alcohol dehydrogenase I gene ADC1, mouse salivary $\alpha$-amylase cDNA, and a segment of yeast $21\mu m$ plasmid. The transformed strain could produce ethanol from starch (4%, w/v) through a direct one-step process with the conversion efficiency of 93.2%, during 5 days of fermentation, while the original, untransformed strain exhibited a conversion efficiency of 38.1% under the same condition. When the regulatory site of the ADC1 promoter region was removed, the production of ethanol increased to 29~37% in the presence of exogenous 3%(v/v) ethanol in the fermentation medium.

• 한국전자통신학회논문지
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• 제4권2호
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• pp.123-129
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• 2009

본 연구에서는 철도 및 공항 등 대형 교통수단의 표시등으로 사용하기 위한 LED 신호등 구동회로를 설계하고 제작된 SMPS의 전기적 특성을 측정하였다. 입력전압 8~12VAC 및 8~16VDC에 대하여 출력전압, 출력전류 및 전력효율은 각각 6VDC, 1.85ADC 및 >70%이었다. 또한 규정한 AC 입력전압에 대하여 측정한 역률은 모두 0.75 이상의 값을 얻었다.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2015년도 춘계학술대회 논문집
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• pp.109-110
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• 2015

알루미늄 합금의 종류중 하나인 ADC12는 가공성이 좋고 가격이 저렴하기 때문에 산업의 많은 분야에 이용할 수 있지만 양극산화를 진행할 시 합금의 주요 구성성분인 실리콘(Si)으로 인해 균열(Crack)이 생기는 문제가 발생하여 이에 따라 균일한 산화막이 생성되지 않다는 단점을 가지고 있다. 이 단점을 극복하기 위해 양극산화를 진행할 때 금속 음이온 성분이 첨가된 전해질을 이용하면 실리콘이 떨어져 나간 부분을 자가치료(Self-healing)할 수 있어 피막의 경도를 포함한 각종 특성이 증가하는 결과를 확인할 수 있다. 본 연구에서는 ADC12를 양극산화할 때 황산 수용액을 기본 전해질로 하여 전해질에 타이타늄(Ti), 마그네슘(Mg), 몰리브덴(Mo)이 포함되어 있는 금속 음이온 물질을 첨가하였고, 금속 음이온 전해질의 농도와 양극산화 진행 시간을 변수로 하여 제조한 산화막의 전기화학적 특성을 SEM(Scanning Electron Microscope), Tafel plot, 그리고 Microvickers hardness tester를 통해 평가하였다.

• 한국주조공학회지
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• 제43권4호
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• pp.210-215
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• 2023

• 대한전자공학회논문지TC
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• 제41권12호
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• pp.77-84
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• 2004

ITS를 위한 차량 충돌 방지 시스템인 FMCW 방식의 자동차 레이더를 분석하고 이에 적합한 신호처리부를 설계하고 구현하였다. 77GHz 대역의 FMCW 레이더에 대하여 성능 파라미터를 거리와 속도 해상도가 각각 0.4m, 0.67Km/h이 되도록 설계하였으며, 다중 물체의 검출을 위한 다수의 비트주파수를 조합하는 방법에 대하여 검토했다. 또한 거리 주파수인 $f_r$과 속도 주파수 $f_d$의 범위를 다르게 설정하여 다중 물체의 처리가 훨씬 간단해지는 것을 보였다. 다중 물체들의 거리차로 인한 감쇄를 보정하도록 미분기를 전처리단에 사용하여 ADC 비트수를 8bit로도 충분히 검출할 수 있음을 보였다. 제안한 방법과 설계한 파라미터 값들을 사용하여 Matlab으로 모의실험으로 검증하고 DSP와 마이크로프로세서를 이용하여 구현하였다.

• 융합신호처리학회논문지
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• 제12권2호
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• pp.139-144
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• 2011

The modern digital logic technology does not yet satisfy the speed requirements of real-time DSP circuits due to synchronized operation of multiplication and accumulation. This operation degrades DSP performance. Therefore, the double-base number system (DBNS) has emerged in DSP system as an alternative methodology because of fast multiplication and hardware simplicity. In this paper, authors propose a novel multiplication architecture. One operand is an output of a flash analog-to-digital converter (ADC) in DBNS format, while the other operand is a coefficient in the IEEE standard floating-point number format. The DBNS digital output from ADC is produced through a new double base number encoder (DBNE). The multiplied output is in the format of the IEEE standard floating-point number (FPNS). The proposed circuits process multiplication and conversion together. Compared to a typical multiplier that uses the FPNS, the proposed multiplier also consumes 45% less gates, and 44% faster than the FPNS multiplier on Spartan-3 FPGA board. The design is verified with FIR filter applications.

• 한국임상수의학회지
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• 제37권6호
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• pp.317-323
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• 2020

The aims of this study were to describe the appearance and size of the normal canine prostate using magnetic resonance (MR) imaging and to calculate the apparent diffusion coefficient (ADC) values. MR images were obtained from seven intact male beagle dogs using a 1.5 T MR unit. The sequences included pre- and post-contrast T1- and T2-weighted imaging with and without fat saturation. The signal intensity of the prostate was compared with the adjacent musculature, fat, and urine in the urinary bladder. We recorded the mean prostatic length, width, and height and the length of the sixth lumbar vertebral body (L6). In addition, the prostatic length (rL), width (rW), and height (rH) ratios to L6 were calculated. Diffusion-weighted images of the prostate were obtained and ADC values were calculated. The prostate was bilobed and oval-shaped, homogenous on T1-weighted images, and heterogeneous with radiating lines on T2-weighted images. Post-contrast T1-weighted sequences showed contrast enhancement of the central and radiating striations. The prostatic capsule was clearly identified on post-contrast T1-weighted images with fat saturation. The ADC values were 1.72-2.04 × 10-3mm2/sec (mean, 1.88 × 10-3mm2/sec). Knowledge of the normal appearance of the prostate on MR images is essential to assess prostatic diseases in dogs.

• 대한전기학회논문지:시스템및제어부문D
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• 제54권11호
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• pp.643-649
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• 2005

A heart diagnosis system adopts Superconducting Quantum Interface Device(SQUD) sensors for precise MCG(MagnetoCardioGram) signal acquisitions. Such system needs to deal with hundreds of sensors, requiring fast signal sampling md precise analog-to-digital conversions(ADC). Our development of hardware board, processing 64-channel 12-bit in 1 ks/s speed, is built by using 8-channel ADC chips, 8-bit microprocessors, SPI interfaces, and specially designed parallel data transfers between microprocessors to meet the 1ks/s, i.e. 1 mili-second sampling interval. We extend the design into 256-channel hardware and analyze the speed .using the measured data from the 64-channel hardware. Since our design exploits full parallel processing, Assembly level coding, and NOP(No Operation) instruction for timing control, the design provides expandability and lowest system timing margin. Our result concludes that the data collection with 256-channel analog input signals can be done in 201.5us time-interval which is much shorter than the required 1 mili-second period.