• Corrosion Science and Technology
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• v.5 no.6
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• pp.206-212
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• 2006

The effects of sub-ppm levels of $H_2S$ and the adsorbed water on the atmospheric corrosion of silver were studied with In situ weight balance to study the effect of the adsorbed water on the kinetic behavior and to determine the rate-controlling step, with XPS to analyze the tarnish film, and with calculation of phase equilibrium to predict the stable solid phase, the concentrations of dissolved species ($Ag^-$, $H^+$, $S^{2-}$, $HS^-$) and the equilibrium potentials ($E_{Ag^+/Ag}$, $E_{H^+/H_2}$, $E_{O_2/O^{2-}$). The results of weight measurements showed that oxygen was required for the sulfidation of silver in 100 ppb $H_2S$ and humidified environments enhanced the tarnished rate and oxidizing power. In addition, the rate determining step for tarnishing silver was shown to be changed to transport though the tarnish film.

• Korean Journal of Optics and Photonics
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• v.14 no.4
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• pp.473-479
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• 2003

The purpose of this study is to recover the CIE XYZ tristimulus values of original colors from scanner output signals, and to reproduce true colors on the monitor. The process of this study is composed of three steps; scanner characterization, chromatic adaptation transformation, and color space transformation between and sRGB. Especially, in the process of recovery, scanner stimuli were obtained accurately by dividing the non-linear photometric response curve into two parts. As the result of test to EPSON Expression 1680 scanner, the average color difference between true and recovered XYZ for 228 target colors, 22 test neutrals, and 36 test colors were 1.49, 0.97, and 1.42 $\Delta$ $E_{UV}$ *, respectively. With the transformation from illuminant D50 to illuminant D65, the input signals to sRGB monitor were predicted. Finally, it could be found that displayed colors with predicted input signals were very consistent with true colors. with true colors.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.141-144
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• 2004

A QVGA active-matrix backplane is produced on a 25${\mu}m$ thin plastic substrate. A 4-mask photolithographic process is used. The insulator layer and the semiconductor layer are organic material processed from solution. This backplane is combined with the electrophoretic display effect supplied by SiPix and E ink, resulting in an electronic paper display with a thickness of only 100${\mu}m$. This is world's thinnest active-matrix display ever made.

• Journal of Nutrition and Health
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• v.29 no.1
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• pp.22-31
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• 1996

The purpose of this study was to investigate the effect of vitamin E and selenium on the antioxidative defense mechanism in the liver of streptozotocin(STZ)-induced diabetic rats. Sprague-Dawley male rats(120$\pm$10gm) were randomly assigned to one control and five STZ-diabetic groups. Diabetic groups were classified to STZ-0E (vitamin E free diet), STZ-40E(40mg vitamin E/kg of diet), STZ-400E(400mg vitamin E/kg of diet), STZ-S(0.5ppm Se/kg of diet) and STZ-400ES(400mg vitamin E and 0.5ppm Se/kg of diet) according to the level of vitamin E and selenium supplementation. Diabetes was experimentally induced by intravenous adminstration of 55mg/kg of STZ in citrate buffer(pH 4.3) after 4-weeks feedng of six experimental diets. Animals were sacrificed at the 4th day of diabetic states. Activities of the serum glutamic oxaloacetate transaminase(GOT) and the glutaminc pyruvate transaminase(GPT) in STZ-0E, STZ-40E and STZ-S rats were higher than those of control. Liver xanthine oxidase activities were similar to serum GOT and GPT. Liver superoxide dismutase(SOD) activities were higher in STZ-0E and STZ-40E groups by 33%, 22%, respectively than that of control. Glutathione S-transferase(GST) activities of liver were similar to GSH-Px activities. The contents of vitamin E in liver tissue were significantly lower STZ-0E, STZ-40E and STZ-S groups by 50%, 36%, 45% than that of control. Reduced glutathione(GSH) contents of liver were lower STZ-0E, STZ-40E, STZ-400E, STZ-S and STZ-400ES groups by 57%, 51%, 19%, 18%, 12% than that of control. Lipid peroxide values (LPO) in liver were higher 5.6, 2.3 and 2.3 times in STZ-0E, STZ-40E and STZ-S group than that of control. The present results indicate that STZ-induced diabetic rats are more sensitive to oxidative stress, leading to the acceleration of lipid peroxidation process, which can be more accelerated by feeding the low level of dietary vitamin E. In the coincident supplementation of high dietary vitamin E and selenium antioxidative enzymes activities and physiolosical antioxidants were increased more than those of the separate supplementation of vitamin E or selenium. Therefore, dietary vitamin E and selenium reduced peroxidative damage of tissue, promoting antioxidative defense mechanism against lipid peroxidation by diabetes.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.9
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• pp.1596-1601
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• 2006

To customer management finds and forecast customer's various pattern more easily and conveniently rising by important topic that control corporation's success and failure, mmy corporations are introducing CRM and eCRM fast. At past, customer management had been managed by statisticians or special statistics package but it is trend been alternating gradually by datamining technique to do to computerize statistics process based on sudden development of IT. Field that this datamining is used representatively is CRM, eCRM. This paper applied datamining using GA referencing customer data or discount store and sale data or 2004 years. forecasted 2005 years melancholy customer by datamining and proved datamining through comparison with actuality customer data is how effective to eCRM.

• Journal for History of Mathematics
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• v.19 no.4
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• pp.117-132
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• 2006

For a meaningful learning of the Construction Unit in 7-B Grade, this study aims to develop teaming materials on the basis of Clairaut's $El{\`{e}}ments$ de $G{\`{e}}om{\`{e}}trie$, which is grounded on a natural generation derived from the history of mathematics and emphasizes students' inquiry activity and reflective thinking activity, and to analyze the characteristics of learning process shown in classes which use the application of teaming materials. Six students were sampled by gender and performance and an interpretive case study was conducted. Construction was specified so as to be consciously executed with emphasis on an analysis to enable one to discover construction techniques for oneself from a standpoint of problem solving, a justification to reveal the validity of construction, and a step of reflection to generalize the results of construction.

• The Journal of Society for e-Business Studies
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• v.23 no.2
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• pp.67-81
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• 2018

Technology commercialization is a reward process for companies' various trials and investment to develop technologies, which can be regarded as a way to figure out company's business performance. To successfully attain companies' purpose via technology commercialization, a variety of knowledge which triggers and completes business activities are needed. This paper suggests a methodology to analyze problems and solutions around the technology commercialization process in terms of knowledge distribution status, especially focused on Korean SMC cases. The knowledge map of this paper is constructed from the knowledge networks and identifies problems and solutions of the target process. A case study for applying proposed concepts to SMC's cases is also performed by checking knowledge distribution status and extracting practical implications. This paper's ideas can be regarded as one of references for SMCs to prepare technology commercialization with guaranteeing facilitated knowledge distribution and utilization.

• Journal of The Korea Institute of Healthcare Architecture
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• v.14 no.4
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• pp.47-54
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• 2008

Preconstruction process in a lean project delivery system was studied in one large healthcare project working for a general contractor. Researchers joined a new lean delivery project for approximately six weeks and participated in preconstruction process including design coordination, management coordination, and target costing while concurrently interviewing other project participants and employees, recording activity in meetings, and otherwise observing the process. The preconstruction process in lean project delivery system, called integrated project design, showed many benefits such as brining expertise of downstream players (i.e., mechanical and electrical contractors) into the design phase. However, lack of leadership and lack of design-integrator blocked the successful application of a new concept of design process.

• International Journal of Korean Welding Society
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• v.3 no.1
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• pp.8-16
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• 2003

A major concern in Gas Metal Arc (GMA) welding process is the determination of welding process variables such as wire diameter, gas flow rate, welding speed, arc current and welding voltage and their effects on the desired weld bead dimensions and shape. To successfully accomplish this objective, 81 welded samples from mild steel AS 1204 flats adopting the bead-on-plate technique were employed in the experiment. The experimental results were used to develop a mathematical model to predict the magnitude of bead geometry as follows; weld bead width, weld bead height, weld bead penetration depth, weld penetration shape factor, weld reinforcement shape factor, weld bead total area, weld bead penetration area, weld bead reinforcement area, weld bead dilution, length of weld bead penetration boundary and length of weld bead reinforcement boundary, and to establish the relationships between weld process parameters and bead geomery. Multiple regression analysis was employed for investigating and modeling the GMA process and significance test techniques were applied for the interpretation of the experimental data.

• Journal of the Society of Naval Architects of Korea
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• v.29 no.1
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• pp.1-13
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• 1992

The objective of this study is to develop knowledge-based system for the preliminary design and midship section design of bulk carrier and to enhance the applicability of knowledge engineering in the field of Naval Architecture. First, expert system shell called E.1 is developed in C language. E.1 supports backward-chaining, automatic iteration procedure and reiterative inference mechanism for efficient application of knowledge-based system in structural design. Knowledge representation in E.1 includes IF-THEN rules, 'facts'and 'tables'. Second, knowledge bases for the principal particulars and midship section design are developed by experimental formula, design standard and experiential knowlege. Third, hybrid system combined this knowledge-based system with the optimization program of midship section is developed. Finally, the simplified design method utilizing the regression analysis of the optimum results of stiffened plate is developed for facilitating the design process. Using this knowledge-based system, the design process and results for Bulk carrier and stiffened plates are discussed. It is concluded that knowledge-based system is efficient for preliminary design and midship section design of the ship. It is expected that the performance of the CAD system would be enhanced if the better knowledge-base is accumulated in the E.1 tool.