• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.6 no.1
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• pp.18-22
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• 2013

Input impedance of the inverted L antenna which is modified from a monopole antenna varies to very high input impedance value when the ratio of vertical height to horizontal length is reduced. So its impedance matching becomes very difficult. In this paper, we analyzed the input impedance variation range depending on the ratio of vertical height to horizontal length in the normal and ferrite thin film added configuration for the input impedance control. For the exact analysis involving the permittivity, permeability and conductivity of ferrite material, FDTD numerical method is used.

• Korean journal of food and cookery science
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• v.19 no.4
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• pp.493-503
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• 2003

The purpose of this study was to investigate the sensory and mechanical characteristics of Mohaebyung by the addition of chestnut, jujube, dried persimmon, pine nut, and codonopsis lanceolata flours. In the sensory evaluation of Mohaebyung, the acceptance for the color, moistness and sweetness was best with the addition of 25% mixed flour. The flavor, grain, chewiness and overall quality were best with the addition of 20% mixed flour. As a result of a textural analysis, the hardness and springiness of Mohaebyung decreased with increases in the addition of mixed flour. The redness, yellowness and lightness of Mohaebyung were increased with increases in the addition of mixed flour. A moisture content of 15% in the mixed flour added to the Mohaebyung was higher with 25% mixed flour.

• Journal of the Korean Applied Science and Technology
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• v.26 no.1
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• pp.93-101
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• 2009

Antistatic acrylic resin is made from n-butyl methacrylate, methyl methacrylate, dimethyl amino ethyl methacrylate(DMAEMA), 2-ethyl hexyl methacrylate, hydroxy ethyl methacrylate, 2,2'-azobis iso-butyronitrile by synthesis. To achieve a lowest surface resistance of antistatic acrylic resin was applied to a variety of synthesis processes. The acrylic resin has been determined from the value of surface resistance and -then the antistatic acrylic resin including dimethyl amino ethyl methacrylate of the 10%, 20% and 30% is synthesized. Finally, dimethyl sulfate(DMS) on a variety of weight ratios is added to antistatic acrylic resin. When DMAEMA / DMS weight ratio is 1/1, antistatic acrylic resin isn't haze the lower the surface resistance. Compared to the traditional antistatic agent, all aspects of the physical properties is outstanding.

• Journal of Fashion Business
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• v.1 no.1
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• pp.43-52
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• 1997

The main purpose of this study was to examine the sectors of Korean textile complex based on various economic characteristics and performances. The sectors in the textile complex differed in many aspects. Man-made fiber industry showed capital-intensive characteristics even though most of the sectors in the textile complex were labor-intensive. Textile industry is composed of weaving and spinning, knitting, dyeing and finishing sectors and even within the textile industry, each sector had different characteristics from each others. Weaving and spinning sector seemed to require relatively high capital investment, while dyeing and finishing was very labor-intensive. Labor-intensive apparel industry has faced decrease in labor-productivity while wage has increased. Slow growth in labor productivity in Korean textile complex was shown to be a more problem than increase in wage or ratio of labor cost to value added. Apparel companies appeared to be in better financial states than the textile companies, even though the exports of apparel products have decreased in the 1990s. However, in overall the financial states of the Korean textile complex were not as strong as those of the other manufacturing sectors.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.11a
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• pp.49-50
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• 2015

Recently, by-products from concrete industry are generated in large quantities because of urban redevelopment. Accordingly, waste concrete powder(WCP) inevitably generated in the course of crushing, screening, and separating the waste concrete also show high emission and be increasing gradually, but which is mostly buried with waste concrete aggregate. This is a basic research to increase the value added utilization rate of WCP. We have examined strength characteristic of extruding panel with WCP, depending on the curing methods. The result of study shows similar strength to the base specimen in autoclave curing condition. And in autoclave curing condition, the specimen with WCP of 20% and 30% satisfy the target strength of 14MPa.

• Journal of Powder Materials
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• v.4 no.2
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• pp.106-112
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• 1997

$Cu-Al_20_3 $ composite powders were prepared by hydrogen reduction of $Cu^{2+}$ from ammoniacal copper sulfate solution on alumina core using autoclave. The copper reduction rate and the properties of copper layer were investigated using Scanning Electron Microscope(SEM), X-ray diffractometer, size and chemical analyzers. The reduction rate of $Cu^{2+}$ showed the maximum value when the molar ratio of [$NH_3$]/[$Cu^{2+}$] was 2. In order to prevent the agglomeration of Cu powder and ethane reduction rate, $Fe^{2+}$ and anthraquinone which act as catalysis were added in the solution. Catalysis was effectively chanced with the addition of two elemerts at a time. Optimum conditions obtained in this study were hydrogen reduction temperature of 205$^{\cire}C$, stirring speed of 500 rpm and hydrogen partial pressure of 300 psi. Obtained $Cu-Al_20_3 $ composite Powders were found to have the uniform and continuous copper coating layer of nodule shape with 3~5 $\mu$m thickness.

• The Korean Journal of Food And Nutrition
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• v.23 no.1
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• pp.114-117
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• 2010

The effects of isolated soy protein(ISP) content on the physicochemical properties of extrudates from rice flour produced by a single-screw extruder were evaluated. The integrity index(II), nitrogen solubility index(NSI), rehydration ratio(RR), and density were measured as indices of the changes of physicochemical properties of rice extrudates. Increased amounts of ISP resulted in increased II but decreased RR and density. There was no change in the NSI value. It was concluded that the addition of ISP to the raw material could be helpful in texturization of rice extrudate.

• Preventive Nutrition and Food Science
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• v.5 no.3
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• pp.148-152
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• 2000

Mussel adhesive protein (MAP) was extracted from Korean Mytilus edulis and then partially purified using Sephacryl S-300 gel permeation chromatography and reversed-phase high performance liquid chromatography. As an indicator of adhesiveness, is 3,4-dihydroxyphenylalanine (DOPA) content was determined. Its DOPA/protein ratio of 0.19 was higher than those of other reports, indicating a good adhesive. The partially purified MAP was confirmed by acid-urea polyacrylamide gel electrophoresis using cetylpiridinium bromide as a cationic detergent. Sea mussel hydrolysates were prepared using three commercial proteases to provide value-added functional materials and their angiotensin converting enzyme (ACE) inhibitory activities were determined. Among hydrolysates of sea mussel, Protamex was the best and further purification would improved ACE inhibitory activity.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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• pp.617-620
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• 1999

To reduce the consumption of chemicals and ultra pure water(UPW) in cleaning process used in device manufacturing, we proposed wet processes that use electrolytic ionized water(EIW), which is generated by electrolysis of a diluted electrolyte solution or UPW and systemically investicate the EIW\`s characteristics. EIW\`s pH values are increased in cathode chamber and decreased in anode chamber according to the electrolysis time and its varied ratio is reduced with time increasement. The variation of pH and ORP is increased accordin to the applied voltage until critical voltage. But more than that voltage, the variation is decreased because of ion\`s scattering effect. When electrolyte is added, the effects of electrolysis is increased because electrolyte acts as catalyst. But when the density of electrolyte is increased more than critical value, ion\`s flowage is obstructed and the effects of electrolysis is decreased.

• The Korean Journal of Food And Nutrition
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• v.10 no.3
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• pp.339-343
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• 1997

To investigate the possibility of making noodle with Chestnuts flour(C.F), it was mixed with wheat flour by the ratio of 70%. Making characteristics of noodle was studied in terms of the viscosity property, cooking quality test, color measurement and sensory evaluation. The viscosity property of noodles with 10~20% C.F was almost same value as control. In the cooking quality test, noodles with 10~30% C.F was almost same value as control in weight, volume and absorbance of cooked noodle. Color difference($\Delta$E) between noodles with C.F was not significantly different from control in color, only noodle with 10% C.F was same as control in texture by sensory evaluation test. Based on the cooking and sensory evaluation test, addition of 30% C.F to wheat flour may be suitable for making noodle.