• Journal of the Semiconductor & Display Technology
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• v.7 no.2
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• pp.55-58
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• 2008

The objective of the research is to design, manufacture and test a Mass Flow Controller(MFC) capable of measuring compressible fluid flows based on a "bucket and stop-watch"method. The basic principle is the measurement of time, where the time taken to fill and empty a bucket of known volume is measured. This method of flow measurement is a new concept when compared to a commercilized current mass flow controller. For the flow meter to be able to compete with established designs it not only must be comparable in cost and robustness, it must be very accurate and reliable as well. This device should be able to handle fluid flows in the range of 0.1ml/min to 10ml/min within an accuracy of ${\pm}$1%. A possible application for a device such as this is in electronics industry where arsenic gas is used in the production of silicon chips.

• The Korean Journal of Zoology
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• v.6 no.2
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• pp.16-20
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• 1963

Gamma 선을 조사한 triglycine용액을 spectrophotometric trechnique와 ultraviolet absorption을 써서 연구하여 다음 결과를 얻었다. 1. 조사된 striglycine-biuret complex 의 dose-yield curve는 방사선의 간접작용을 보여주는 전형적인 예를 보여주었다. 2. G(CO-NH)는 s1.75였다. 3. Dose-yield data에서 보면 peptide bond reputure는 선량을 증가함에 따라서 감소하는 증가율을 나타내어 분해산물들이 free radical 과 compete함을 알 수있었다. 4. 증가된 triglycine의 molecular extinction coefficient는 5 $\times$1020 ev./ml가지는 비례적증가를 나타내었고 이보다 높은 선량에서는 1.9$\times$1021 ev/ml 에 이르기까지 직선적 감소를 보여 carbonyl compound 의 G치는 0.80이였다.

• KDI Journal of Economic Policy
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• v.38 no.1
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• pp.93-121
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• 2016

The excessive demand for universities in metropolitan areas as a result of location premiums and regulated admissions quotas diminishes the competition between universities and the incentive to enhance educational performance to attract more students. Cases in point are the lower graduate employment rates (a measure of educational performance) of universities in metropolitan areas compared to those in non-metropolitan areas despite higher quality students. Additionally, the graduate employment rates of non-metropolitan universities are influenced by educational input factors such as an increase in the percentage of courses taught by full-time faculty, while those of metropolitan universities are contingent merely on enrollees' entrance scores. Ergo, a structure that revitalizes the competition between universities and encourages them to improve their educational services must be established in order to enhance the quality of higher education.

• Proceedings of the Korea Contents Association Conference
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• 2008.05a
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• pp.419-421
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• 2008

Recently, the mobile telecommunication industry is increasing rapidly; nevertheless it is competing severely with other mobile telecommunication industries in the world and it is projected that in the future the mobile telecommunication industry will compete more fiercely and increase more rapidly. By means of looking into characteristics of the mobile, therefore, it can be said that it can help the companies which want to survive in such a competitive society.

• Transactions on Electrical and Electronic Materials
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• v.17 no.4
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• pp.204-207
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• 2016

Experimental study of UV-irradiated O₂/H₂ gas phase cleaning for PMMA (Polymethylmethacrylate) removal is carried out in a load-locked reactor equipped with a UV lamp and PBN heater. UV enhanced O₂/H₂ gas phase cleaning removes polymethylmethacrylate (PMMA) better at lower process pressure with higher content of H₂. O₂ gas compete for UV (184.9 nm) absorption with PMMA producing O₃, O(¹D) and lower dissociation of PMMA. In our experimental conditions, etching reaction of PMMA at the substrate temperature between 75℃ and 125℃ had activation energy of about 5.86 kcal/mol indicating etching was controlled by surface reaction. Above the 180℃, PMMA removal was governed by a supply of reaction gas rather than by substrate temperature.

• Toxicological Research
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• v.14 no.4
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• pp.557-562
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• 1998

Allyl alcohol is metabolized in the liver through two steps, first to reactive acrolein by alcohol dehydrogenase (ADH), subsequently to acrylic acid by aldehyde dehydrogenase (ALDH). Since ethanol could compete the same enzymes to be metabolized in the liver, we have determined the plasma concentrations of allyl alcohol and ethanol followed by combined treatment. Pretreatment of rats with 2g/kg ethanol followed by ip administration of 40mg/kg allyl alcohol increased the lethality significantly. Determination of in vivo blood concentrations revealed that ethanol pretreatment caused the apparent decrease in allyl alcohol clearance, whereas acetaldehyde level in blood increased significantly by allyl alcohol treatment, as determined by head space GC analysis. Treatment of 4-methylpyrazole, an inhibitor of ADH, delayed allyl alcohol elimination significantly and reduced its lethality. Collectively, these findings suggested that reduction of allyl alcohol clearance in the presence oj ethanol was mediated through ADH competitive inhibition.

• Journal of Information Technology Services
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• v.5 no.1
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• pp.165-175
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• 2006

Electronic commerce has many advantages compared to the traditional way of doing business such as up to date information and rich service for less cost. There is a growing number of electronic commerce applications on the Internet. Using software agent technology, the market framework offers timesaving automation of auctions and flexibility through negotiations among the agents. In this research, we attempt to evaluate the performance of a negotiation decision function that considers the potential competitors in competitive market environment as well as that of a negotiation decision function that does not. For this evaluation, this study adopts the electronic marketplace as an application domain in which many sellers and buyers compete for limited resources in the marketplace.

• Preventive Nutrition and Food Science
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• v.3 no.2
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• pp.119-122
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• 1998

Pumpkin venegar was produced using autoclaved pumpkin juice by fermenting with cetobacter starter and ethanol at the ratio of 4 % and 10% to the volume of pumpkin juice, respectivley. Fermentation was carried out at 2$0^{\circ}C$ for 14 days followed by aging at 1$0^{\circ}C$ for 14 days. Flavor components of pumpkin vinegar was determined using GC/MS. Identified components, were 2 aldehydes (4.74%), 5 acohols (30.06%), 4 ketones (8.99%), 4 acids (16.39%), 5 alkanes (11.10%), 11 miscellaneous compounds (27.01%) and 9 unknown compounds (1.71%). Pumpkin vinegar showed very similar flavor characteristics to those of conventional wien vinegar and sherry wine vinegar in particular , acetioin, methyl acetate, and butanoic acid were typical volatile components of these three kinds of vinegar. Pumpkin vinegar showed possiblity to compete with European wine vinegar.

• Applied Science and Convergence Technology
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• v.27 no.5
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• pp.79-85
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• 2018

Many studies have been conducted on large-scale graphene synthesis by chemical vapor deposition. Furthermore, numerous researchers have attempted to develop processes that can continuously fabricate uniform and high-quality graphene. To compete with other types of carbon materials (carbon black, carbon fiber, carbon nanotubes, and so on), various factors, such as price, mass manufacturing capability, and quality, are crucial. Thus, in this study, we examine various large-scale graphene production methods focusing on cost competitiveness and productivity improvements for applications in various fields.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.03a
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• pp.570-573
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• 2008

In spite of many experimental studies of low-power applied-field magnetoplasmadynamic(AFMPD) thrusters, thrust efficiencies of the past thrusters are very low. Hence, drastic improvement in thrust performance is required for AF-MPD thrusters to compete against other types of electric propulsion in a moderate power regime around 10 kW. For the optimization of AF-MPD thrusters, a numerical code for the flowfield simulation is now under development. A preliminary result shows that the code can deal with a complicated mixture of the induced and applied magnetic fields, which will lead to a combination of the self-field, swirl, Hall, as well as electrothermal accelerations.