• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2002.04a
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• pp.53-58
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• 2002

This paper aims to synthesize the research on fatigue mechanisms of high strength aluminum alloys which are widely used in motorcars or airplanes to prevent accidents. To measure the data of crack opening ratio, the same materials and methods are used for evaluating the fatigue crack propagation rate as an effective stress intensity factor. But, many researchers have brought different results. An exact crack opening ratio was, therefore, proposed for getting a more accurate fatigue crack propagation rate.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1997.10a
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• pp.224-227
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• 1997

The objective of this study is to propose a new procedure to synthesize the multi-experts priorities in AHP. To aggregate the multi-experts priorities, in this paper, we suggest a way which Decision Maker can exclude outlier matrix from group using the concept of the compatability and we introduce Delphi method to use compatability in AHP. Some numerical example are shown to illustrate the procedure.

• Archives of Pharmacal Research
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• v.14 no.3
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• pp.279-281
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• 1991

In the field of cephalosporins, introduction of quaternary heterocyclic methyl goups at the C-3 position has led to a new class of cephalosporins such as cefepime and cefpirome, the so-called 4th generation cephalosporins which are characterized by their potent activity. Since than many efforts were attempted to synthesize more effective analogs.

• Proceedings of the Korean Society of Food Hygiene and Safety Conference
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• 1994.06a
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• pp.29-39
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• 1994

A review on sweetener has been conducted. Enzymes are utilized preferentially to break-down or synthesize stevioside, MGGR and oligo-saccharides. these result in change or modification of the functions of sweetener. Originally, the sweetener was used to obtain energy, add sweet taste and for rheological properties. Recently, the physiological functions of the sweetener have been studied considerably. As the oligo-sacchride is found to function as substance of physiological activities, more researh will be carried out using enzyme to discover new functions of sweetener.

• Proceedings of the KSR Conference
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• 2002.10b
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• pp.892-897
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• 2002

The research was requested by Meridian Rail Corporation in United States. The Swing Motion Bogie can application by Korea style if synthesize study result of bogie strength evaluation, bogie dynamic characteristics analysis, actual test(maximum speed, derailment coefficient, lateral force, vertical force, vibration acceleration, steady state lateral acceleration) etc..

• Journal of Korean Society of Industrial and Systems Engineering
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• v.14 no.24
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• pp.155-161
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• 1991

Flexibility has become a key objectives in the design of manufacturing systems and a critical measure of total manufacturing performance. The need for flexibility is increasing due to some environmental change such as changing technical characteristics of the products and the changing nature of market demands. Most importantly, flexibility embodies competitive value for a manufacturer. Although the importance of flexibility has stressed in the various research, very few attempts have been made to synthesize the literature dealing with definitions and measure of flexibility. It is this issue that have motivated us to search for the definition and classification of flexibility.

• Bulletin of the Korean Chemical Society
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• v.28 no.1
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• pp.73-76
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• 2007

Prunioside A, isolated from the methanol extract of Spiraea prunifolia var. Simpliciflora's root, is composed of coumaroyl, monoterpene-type, and glucosyl units. The esterase activity of tannase was used to remove the p-coumaroyl and glucopyranosyl groups. The enzymatically hydrolyzed compound was reacted with various acyl chlorides to synthesize its ester derivatives, which showed the inhibitory effects on NO production in murine machrophage?like RAW 264.7 cells stimulated with lipopolysaccharide and interferon-γ.

• Proceedings of the KIEE Conference
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• 2007.11a
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• pp.112-113
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• 2007

We synthesize ZnO nanowires (NWs) doped with 3 wt% Ga on sapphire substrate using a hot-walled pulsed laser deposition (PLD) system named PLD in Furnace. A proprietary target rotating system is employed in the furnace to ensure the homogeneity of the deposition. The kinetic energy of the laser-ablazed ZnO is controlled for the optimization of NW formation. The physical properties of the resultant NWs are presented.

• Journal of the Korean Chemical Society
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• v.53 no.5
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• pp.536-541
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• 2009

Sulphamic acid has been exploited as a cost-effective catalyst and green alternative for conventional acidic materials to synthesize $\alpha$-hydroxy phosphonates under solvent-free condition. The reaction carried out using ultrasound irradiation with better yields and shorter reaction time.

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.10a
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• pp.16.2-16.2
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• 2011

Graphene has attracted significant attention due to its unique characteristics and promising nanoelectronic device applications. For practical device applications, it is essential to synthesize high-quality and large-area graphene films. Graphene has been synthesized by eloborated mechanical exfoliation of highly oriented pyrolytic graphite, chemical reduction of exfoliated grahene oxide, thermal decomposition of silicon carbide, and chemical vapor deposition (CVD) on metal substrates such as Ni, Cu, Ru etc. The CVD has advantages over some of other methods in terms of mass production on large-areas substrates and it can be easily separated from the metal substrate and transferred to other desired substrates. Especially, plasma-enhanced CVD (PECVD) can be very efficient to synthesize high-quality graphene. Little information is available on the synthesis of graphene by PECVD even though PECVD has been demonstrated to be successful in synthesizing various carbon nanostructures such as carbon nanotubes and nanosheets. In this study, we synthesized graphene on $Ni/SiO_2/Si$ and Cu plate substrates with CH4 diluted in $Ar/H_2$ (10%) by using an inductively-coupled PECVD (ICPCVD). High-quality graphene was synthesized at as low as $700^{\circ}C$ with 600 W of plasma power while graphene layer was not formed without plasma. The growth rate of graphene was so fast that graphene films fully covered on substrate surface just for few seconds $CH_4$ gas supply. The transferred graphene films on glass substrates has a transmittance at 550 nm is higher 94%, indicating 1~3 monolayers of graphene were formed. FETs based on the grapheme films transferred to $Si/SiO_2$ substrates revealed a p-type. We will further discuss the synthesis of graphene and doped graphene by ICPVCD and their characteristics.