• Journal of the Korean Crystal Growth and Crystal Technology
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• v.8 no.2
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• pp.278-285
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• 1998

It was known that the C-IC transition in the mixed crystal $(A_{1-x}A^'_x)_2ZnCl_4$ is smeared out with increasing x, which is attributed to the pinning effect of the doped A' ions. In this study, we introduce a new mixed crystal system $K_2Zn_{1-X}Co_XCl_4$, where doped Co ions do not destroy the orientation of the polarization in C phase and preserve the long range ordering of IC phase. We grew a series of mixed crystals $K_2Zn_{1-X}Co_XCl_4$ for x=0, 0.001, 0.005, 0.01, 0.05, 0.1, 0.3, 0.5, 0.7, 1 by the Czochralski method and investigated the real composition of the mixed crystals, structure and the change of the C-IC phase transition with increasing x by the thermal analysis.

• Proceedings of the KIEE Conference
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• 2001.11c
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• pp.209-211
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• 2001

The core in developing the transformer-operated 3 phase solid state meter is to design a single chip IC, that incorporates all the necessary features required for development of the 3 phase solid state meter. Using this technology, the solid state meter can be mass produced at lower cost and higher quality. This report deals with the performance of the prototype FPGA board, which is the final step before actual IC fabrication in fabrication LAB. All the features of FPGA board, shown in this report will be included in the final ASIC IC product.

• Microbiology and Biotechnology Letters
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• v.31 no.1
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• pp.51-56
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• 2003

The angiotensin I converting enzyme (ACE) has an important role in the maintenance of blood pressure. The ACE inhibitory activities of foods have recently been studied. We tried to isolate ACE inhibitory peptides from the Flavourzyme (FZ), Pescalase (PE), and Thermolysine (TH) protease digests of corn gluten, which was restricted to the use the source of food for digestion problem. The FZ, PE, TH/PE protease hydrolyzed corn gluten and the inhibitory activities of the hydrolyzates for ACE were measured. Major fractions were isolated from the digests using ODS chromatography after treating with ethanol in step gradient. The ACE inhibitors were further purified by Bio-Gel P-2 column and reverse phase HPLC. Five inhibitory peptides were isolated. Their amino acids were sequenced as LPF ($IC_{50}$ = 40$\mu$M), GPP ($IC_{50}$ = 17.6$\mu$M), PNPY ($IC_{50}$ = 30.7$\mu$M), SPPPFYL ($IC_{50}$ = 63 $\mu$M), and SQPP ($IC_{50}$ = 17.2$\mu$M).

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1140-1141
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• 2007

A method of modeling the Smart Power IC is presented in this paper, which is based on the IC's typical operation characteristics and small signal frequency response data. Using the least square identification, the IC's dynamic mathematical model, which is expressed as transfer function, can be synthesized from the experimentally obtained gain and phase data. The practicability and effectiveness of the method are verified by means of experiments.

• Journal of the Korean Chemical Society
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• v.53 no.2
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• pp.137-143
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• 2009

Liquid chromatographic enantiomer separation of N-tert-butoxycarbonyl (BOC) $\alpha$-amino acids and their ethyl esters was performed on covalently immobilized chiral column (Chiralpak IC) derived from polysaccharide derivative. The solvent versatility of the covalently immobilized Chiralpak IC in enantiomer separation of N-BOC $\alpha$-amino acid ethyl ester derivatives was shown and the chromatographic parameters of their enantioselectivities and resolution factors were greatly influenced by the nature of the mobile phase. Also the effect on the dissolving solvent for these analytes on the enantiomer separation using the same mobile phase and the examples of preparative enantiomer separation on analytical column were shown.

• JSTS:Journal of Semiconductor Technology and Science
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• v.15 no.4
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• pp.484-492
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• 2015

This paper proposes a PWM phase-shift circuit to make that the LED lighting system distributes the channel currents evenly for any number of LED strings by generating evenly phase-shifted PWM signals for multiple LED driver ICs. The evenly distributed channel currents reduce the peak current, the decoupling capacitor size, and EMI noise. The PWM phase-shift circuit makes an arbitrary degree of PWM phase-shift by using a resistor and a capacitor. It measures the RC delay once. It reduces the number of external resistors and capacitors by providing zero and 180 degree phase-shift modes requiring no resistor and capacitor. An LED driver IC with the PWM phase-shift circuit was fabricated with a $0.35{\mu}m$ BCDMOS process. The PWM phase-shift circuit receives a PWM signal of 50 Hz~20 kHz at $f_{CLK}=450kHz$ and it generates a $0{\sim}360^{\circ}$ phase-shifted PWM signal with $R=0{\sim}1.1M{\Omega}$ at C=1 nF and $f_{PWM}=1kHz$. The measured phase errors are 1.74~3.94% due to parasitic capacitances.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.8A
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• pp.1252-1258
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• 1999

This paper describes a COMS IF transceiver IC for 10-MHz bandwidth wireless local loops. It interfaces between the RF section and the digital MODEM section and performs the IF-to-baseband (Rx) and baseband-to-IF (Tx) frequency conversions. The chip incorporates variable gain amplifiers, phase-locked loops, low pass filters, analog-to-digital and digital-to-analog converters. It has been implemented in a 0.6 -${\mu}{\textrm}{m}$ 2-poly 3-metal CMOS process. The phase-locked loops include voltage-controlled oscillators, dividers, phase detectors, and charge pumps on chip. The only external complonents are the filter and the varactor-tuned LC tank circuit. The chip size is 4 mm $\times$ 4 mm and the total supply current is about 57 mA at 3.3 V.

• The Transactions of the Korean Institute of Power Electronics
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• v.9 no.4
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• pp.311-318
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• 2004

Generally, PM BLDC drive system is necessary that the three Hall-ICs evenly be distributed around the stator circumference and encoder installed in case of the 3 phase motor. The Hall-ICs are set up in this motor to detect the main flux from the rotor. So the output signal from Hall-ICs is used to drive a power transistor to control the stator winding current. Instead of using three Hall-ICs and encoder, this paper uses only two Hall-ICs for the permanent magnet rotor position and for the speed feedback signals, and uses a micro controller of 16-bit type(80C196KC) with the 3 phase PM BLDC whose six stator and two rotor designed. Two Hall-IC Hc and $H_B$ are placed on the endplate at 120 degree phase difference. With these elements, we estimate information of the other phase in sequence through a rotating rotor.

• The Transactions of the Korean Institute of Power Electronics
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• v.10 no.2
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• pp.109-116
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• 2005

The high performance drives of the slotless Permanent Magnet Brushless DC(PM BLDC) motor can be achieved by the current control, where the currents flow according to the rotor position and the current phase is suitably controlled according to the operational condition. Rotor position information can be provided by Hall-IC or sensorless algorithm. So, the Hall-ICs are set up in this motor to detect the main flux from the rotor. Instead of using three Hall-ICs and encoder, this paper uses only two Hall-ICs for the permanent magnet rotor position and the speed feedback signals, and uses a micro-controller of 16-bit type (80C196KC). Also because of low resolution obtained by using Hall-IC even low-cost and simple structure, to improve the wide range of speed response characteristic more exactly, we propose the rotor position signal synthesizer using PLL circuit based on two Hall-ICs.

• Proceedings of the KIEE Conference
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• 2000.11d
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• pp.644-646
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• 2000

According to the deregulations of governments in the world. the power industries of United State and European nations are proceeding remote meter reading and remote load control. But the core technology of multifunctional electronic meter implemented by programmable one-chip IC, which can be the right answer of all the power industy's efforts is now still under development in the advanced countries. Implementation of smallest size, lowest price single-phase meter with features which enable distribution automation such as bidirectional communication, Remote load control, remote meter reading, remote credit assigment. Prepayment billing system.