• Proceedings of the IEEK Conference
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• 2001.06b
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• pp.253-256
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• 2001

This paper introduces the design of high-speed analog- to-digital converter for high-definition TV, camcorders, portable equipments and implemented in a 0.65${\mu}{\textrm}{m}$ CMOS technology. Key circuits developed for low power and high speed A/D converter are a dynamic comparator that consumes no static power, a source follower buffered op amp that achives wide bandwidth using large input devices. The converter achieves low power dissipation of 40-mW at 3.3-V power supply. Measured performance includes 0.53 LSB of INL and 0.48 LSB of DNL while sampling at 60MHz.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07a
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• pp.581-584
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• 2003

The phase differences and noise signals are in general serious on output of a instrumentation amplifier for signal conditioning of a sensor driven at high frequency due to a time-varying input signal. In this study, we get the better amplification and S/N ratio using the rectified signal for the input of instrumentation amplifier. This driving circuits were designed and constructed by OrCAD and laboratory PCB process. All of the elements used on the circuit including highly speedy OP-Amp. was SMD type and the MI sensor was fabricated by meander-patterned amorphous ribbon. The output sensitivity of this circuit was $105.3mV/V{\cdot}Oe$. That's why this driving circuit is good at detection of fine magnetic field.

• Journal of environmental and Sanitary engineering
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• v.11 no.3
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• pp.69-77
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• 1996

The result of isolated and selected to the strain having the emulsifying activity from soil's strain the strain was identified as Candida genus. The strain was investigated with culture condition at pH culture temperature, flow rate of air, strring rate etc., and physicochemical properties of the biosurfactant were examined. The optimum composition of medium for a strain cultivation were obtained as follow : glucose ; 100g/L, yeast extract ; 10g/L, urea ; 1.0g/L, KH$_{2}$PO$_{4}$ ; 50mg/L, MgSO$_{4}$ ; 500mg/L, and the op condition of cultivation was as follow : pH ; 3.0, temperatlue ; 24$\circ $C, strring rate ; 40rpm. The maximum yield of biosurfactant was obtained by pH ; 3.0-3.5, and temperature ; 25$\circ $C. The degree of emulsification of syntesized biosurfactant was increased clearly by increasing concentration of biosurfactant and it's stability was maintained for a long time. The surface tension of biosurfactant was varied with pH, especially it was showed that the surface tension was high at acidic pH.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.43 no.2
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• pp.285-295
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• 1994

Double Injection(DI) switching devices consist of PS0+T and nS0+T contact separated by a nearly intrinsic semiconductor region containing deep trap. The equation set for DI switching device simulation by FEM is proposed. The existance of deep trap requires the modification of conventional equation set. So recombination rate equation is modified and a new equation is included in the equation set which conventionally consists op Poisson equation and current continuity equation. Consequently, the modeling equation set, which is proposed in this paper, can be applied to other semiconductor devices with trap.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.9 no.1
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• pp.25-29
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• 1984

The active compensation of operational amplifeir is that it compensates the phase shift and the attennation of gain of OP Amp, according as the frequency increases. The compensation circuit is applied to VCVS and interting integrator. For VCVS, the phase shift of proposed compensated circuit is not concern with the frequency and the gain chracteristic is better than the proposde circuit by Soliman, according as the rate of feedback resistors of compensated circuit changes. Voltage follower accomplishies compgnsation using the same circuit. Also, the compensation circuit to increase O-ffactor in inverting integrator is proposed.

• Bulletin of the Korean Chemical Society
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• v.21 no.7
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• pp.675-678
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• 2000

The reaction between silver (I) and thiomicher's ketone (TMK) was sensitive at pH 5 and 8 in the presence of non-ionic or anion surfactant. We studied the complex solution and determined the properties by beta-correction spectrophotometry, which included the complex ratio and the stability constant of the complex. The results showed that complex Ag(TMK)2 was formed in the presence of alkylphend ethoxylates (emulsifier OP) and Ag(TMK)2 was formed in the presence of sodium dodecyl benzene sulfonate (SDBS). Their real absorptivities are as follows: $\varepsilonAg(TMK)540$ = 5.23 ${\times}$ 10(4), $\varepsilonAg(TMK)2(555)$ = l.05 ${\times}$ 10(5) Lmol(-l)cm(-1) both at pH 5 and $\varepsilonAg(TMK)2(555)$ = 7,52 ${\times}$ 10(4)lmol(-1)cm(-1) at pH 8. The stability constant of complex Ag(TMK) was equal to 1.23 ${\times}$ 10(5) at pH 5 and that of Ag(TMK)2 8.29 ${\times}$ 10(9) at pH 5 and 1.15 ${\times}$ 10(11) at pH 8.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.42
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• pp.15.1-15.8
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• 2020

Background: Reconstructing maxillofacial defects is quite challenging for most surgeons due to the region's complex anatomy and cosmetic and functional effects on patients. The use of pre-made alloplastic implants and autogenous grafts is often associated with resorption, infection, and displacement. Recent technological advances have led to the use of custom computer-designed patient-specific implants (PSIs) in reconstructive surgery. This study describes our experience with PSI, details the complications we faced, how to overcome them, and finally, evaluates patient satisfaction. Case presentation: Six patients underwent reconstruction of various maxillofacial defects arising due to different etiologies using PSI. A combined total of 10 implants was used. PEEK was used to fabricate 8, while titanium was used to fabricate 2. No complications were seen in any patient both immediately post-op and in subsequent follow-ups. All patients reported a high level of satisfaction with the final result both functionally and cosmetically. Conclusion: The use of computer-designed PSI enables a more accurate reconstruction of maxillofacial defects, eliminating the usual complications seen in preformed implants and resulting in higher patient satisfaction. Its main drawback is its high cost.

• Korean Journal of Food Science and Technology
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• v.37 no.1
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• pp.30-37
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• 2005

To mass-produce useful biopolymer films, chitosan/gelatin blend films were prepared by solution casting method. Effects of mixing ratio, tensile strength (TS), elongation (E) at break, total color difference (${\Dalta}E$), opacity, water vapor permeability (WVP), oxygen permeability (OP), and thermal properties on chitosan/gelatin blend films properties were investigated. TS, E, ${\Dalta}E$, opacity, WVP, and OP values were 58.24-22.01 MPa, 13.11-24.67%, 1.86-17.45, 0.3104-1.2161 nmO.D./${\mu}m$, $1.6875-1.7225ng{\cdot}m/m^{2}{\cdot}s{\cdot}Pa$, and $2.2380{\times}10^{-7}-2.2975{\times}10^{-7}\;mL{\cdot}{\mu}m/m^{2}{\cdot}s{\cdot}Pa$, respectively. TS of blend films decreased, while E, ${\Dalta}E$, and opacity increased with increasing chitosan content. WVP of blend films did not show any significant relationship with mixing ratio and thickness of blend films. Miscibility of films was examined over entire composition range by thermogravimetric analyzer (TGA) and dynamic mechanical analyzer (DMA). TGA results showed gelatin is more thermally stable than chitosan and some interactions among functional groups of two biopolymers. Glass transition temperature $(T_{2})$ of films as determined by DMA decreased with increasing content of chitosan in the blend. Results of thermal analysis indicate high miscibility among polymer components in the blend.

• Journal of the Korean Applied Science and Technology
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• v.39 no.5
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• pp.605-613
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• 2022

The genus Flavobacterium, type genus of the family Flavobacteriaceae and a member of the phylum Bacteriodetes includes gram-negative and yellow-pigmented rods. Those bacteria have been isolated from various environments of the earth. A yellow-pigmented, gram-negative rod was isolated from a pond in the campus of the Changwon University, Changwon, Kyeongnam and designated as strain B1. Strain B1 was further analyzed physiologically, biochemically and phylogenetically, and concluded to be a member of genus Flavobacterium. BLAST search of the 16S rRNA gene sequence of strain B1 shows homology no higher than 99.0% with those sequences of other bacteria. The major fatty acids of strain B1 are iso-C_15:0 (19.6%), summed feature 3(C_16:1 ω7c and/or C_16:1 ω6c, 16.1%), iso-C_17:0 3OH(10.2%), iso-C_15:0 3OH(8.4%) and iso-C_15:1 G(6.6%) showing significant differences in fatty acid compositions between strain B1 and the other known Flavobacterium species. DNA sequence of 16S rRNA gene of strain B1 was deposited in genbank under accession number OP060681.

• Journal of the Korean Society of Fashion and Beauty
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• v.2 no.2 s.2
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• pp.1-11
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• 2004

The purpose of this study was to analyze the hair style trend in the respect of fashion trend in 1960s. The study also attempted if there were significant influences to current hair designers and hair styles as beehive, mods hair, short cut. geometric cut, wigs, natural hair, unisex hair. This study is a descriptive study, involving the collection of picture data and examine the art of the 1960's. Because 1960's is a revolutionary decade in the way of living and fashion trend. This study also adopted review of literature and analysis of magazines. 1960's was a period of major street fashion as Mods, Jackie Look, Miniskirt, Pop Art, Op Art Look, Space Look, Hippie Look, Unisex Look. The results of this study can be summarized as follows: 1) A review of literature had shown that little or no studies for an in depth analysis of 1960's fashion trend and hair design. 2) During the sixties, the trend of fashion and hair style were remarkable change in the way of living. 3) There were strong influences hair styles of 1960's until today.