• Proceedings of the Optical Society of Korea Conference
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• 2009.10a
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• pp.86-87
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• 2009

• Proceedings of the Optical Society of Korea Conference
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• 2007.02a
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• pp.351-352
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• 2007

• Proceedings of the Optical Society of Korea Conference
• /
• 2007.02a
• /
• pp.100-101
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• 2007

• Journal of Advanced Marine Engineering and Technology
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• v.19 no.4
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• pp.1-6
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• 1995

Recently, outstanding progresses have been made in food industry, in all the processes involved in the conversion of raw materials into food products. This article describes two kinds of coolers for processing uncooded foor, namely vacuum coolers capable of rapidly cooling decomposing bacteria down to their critical temperature, and also cooling equipment for fresh vegetables based on the same principle as the vacuum cooler.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2012.10a
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• pp.628-629
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• 2012

• Proceedings of the Optical Society of Korea Conference
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• 2008.02a
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• pp.311-312
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• 2008

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2013.10a
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• pp.303-304
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• 2013

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• v.5B no.3
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• pp.277-282
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• 2005

This paper describes a step-down AC voltage regulator using an AC chopper and auxiliary transformer, which is a series connected to the main input. The detail design of the AC regulator, logic and PWM pattern of the AC chopper is described and the three-phase AC regulator using two single­phase AC choppers with a three transformer configuration is proposed for three-phase application. The proposed three-phase system has the advantages of lower system cost due to reduced switch number and gate driver circuit as well as advantages of decreased size and weight because it uses a series compensated scheme. The proposed AC regulator has many benefits such as fast voltage control, high efficiency and simple control logic. Experimental results indicate that it can be used as a step-down AC voltage regulator for power saving purposes very efficiently.

• ETRI Journal
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• v.26 no.6
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• pp.555-559
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• 2004

We propose an efficient digital IF down converter architecture for dual-mode WCDMA/cdma2000 based on the concept of software defined radio. Multi-rate digital filters and fractional frequency conversion techniques are adopted to implement the front end of a dual-mode receiver for WCDMA and cdma2000. A sub-sampled digital IF stage was proposed to support both WCDMA and cdma2000 while lowering the sampling frequency. Use of a CIC filter and ISOP filter combined with proper arrangement of multi-rate filters and common filter blocks resulted in optimized hardware implementation of the front end block in 292k logic gates.

• Journal of IKEEE
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• v.12 no.1
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• pp.34-42
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• 2008

This paper proposes a new on-chip voltage down converter(VDC), which employs a new reference voltage generator(RVG). The converter adopts a temperature-independence reference voltage generator, and a voltage-up converter. The architecture of the proposed VDC has a high-precision, and it was verified based on a 0.25${\mu}m$ 1P5M standard CMOS technology. For 2.5V to 1.0V conversion, the RVG circuit has a good characteristics such as temperature dependency of only 0.2mV/$^{\circ}C$, and the voltage-up circuit has a good voltage deviation within ${\pm}$0.12% for ${\pm}$5% variation of supply voltage VDD. The output voltage is stabilized with ${\pm}$1mV for load current varying from 0 to 100mA.