• Journal of the Korea Organic Resources Recycling Association
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• v.16 no.3
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• pp.65-74
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• 2008

In this study, the composition and physico-chemical characteristics of municipal solid waste (MWS) which was treated in four different area were investigated. It is necessary to measure the characteristics of MSW to build a waste treatment and Refuse Derived Fuel (RDF) facility, the data-base and total managing of the landfill. It was found that the average density of solid wastes is in the range of $78.15-199.8kg/m^3$. This MSW was composed of 8.87% of food wastes, 38.8% of papers, 34.12% of plastics & vinyls, 7.16% of textiles, 0.96% of wood, 1.3% of rubber & leathers and others, respectively. Most of MSW are composed of food, paper and plastic waste and more than 94% was combustible waste. For three components, moisture is 17.38%, combustible component is 69.03% and ash is 6.24%. The chemical element has the high order of carbon, oxygen, hydrogen on the dry basis of wastes. And the low heating value of the MSW which is measured by calorimeter is calculated as 2973.8 kcal/kg and high heating value of the MSW is calculated as 5209.94 kcal/kg.

• Journal of the Korean Vacuum Society
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• v.1 no.1
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• pp.106-114
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• 1992

Abstract-Quantitative surface analysis of Co-Ni and Au-Cu alloys by XPS and SIMS was studied. For Co-Ni alloy, quantitative XPS analysis could be done within 1-2% relative error with pure element standards without any correction. For Au-Cu, quantitative XPS analysis was not possible without any correction. But it could be done with standard alloys of various composition within 1-2% relative error. Without standard alloys, Au-Cu alloys could be analyzed by XPS within 10% relative error with pure element standards. For SIMS analysis of Co-Ni alloys, the relative secondary ion yields of Co+/Nit has linear relation with ratio of each composition so that quantitative SIMS analysis was possible for Co-Ni alloys. Preliminary results of XPS round robin test of VAMAS-SCA Japan Project are given.

• Journal of the Korean Ceramic Society
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• v.55 no.4
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• pp.368-375
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• 2018

This study deals with the color formation of ceramic pigment in the $TiO_2$-SnO-ZnO system. We designed compounds to control the color formation depending on the composition using the Design of Experiment. The color coordinate values of synthesized pigments, $L^*a^*b^*$ were measured and statistically analyzed color for changing elements depending on its composition. The relationship between the major crystalline phases and chromaticity was examined using XRD, and the oxidation states of each element were analyzed by XPS. The synthesized pigments based on the compound design exhibited various color changes ranging from yellow-orange to green-blue and brown. The statistical analysis on the spectrophotometer results shows that $a^*$ and $b^*$ values decreased with $TiO_2$ content, and increased with SnO content. Yellow-orange color was detected with the main peak of SnO, and the green-blue color developed with the main peak of $Zn_2TiO_4$. The $a^*$ and $b^*$ values increased with increased SnO peak intensity, and decreased with increased $Zn_2TiO_4$ peak intensity. The results revealed that pigment color formation was influenced by changes in the main crystalline phases and crystalline intensity. However, XPS analysis of the oxidation states of each element showed little correlation with the pigment chromaticity result.

• Restorative Dentistry and Endodontics
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• v.43 no.3
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• pp.32.1-32.11
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• 2018

Objectives: This study evaluated the effects of a bleaching agent on the composition, mechanical properties, and surface topography of 6 conventional glass-ionomer cements (GICs) and one resin-modified GIC. Materials and Methods: For 3 days, the specimens were subjected to three 20-minute applications of a 37% $H_2O_2$-based bleaching agent and evaluated for water uptake (WTK), weight loss (WL), compressive strength (CS), and Knoop hardness number (KHN). Changes in surface topography and chemical element distribution were also analyzed by energy-dispersive X-ray spectroscopy and scanning electron microscopy. For statistical evaluation, the Kruskal-Wallis and Wilcoxon paired tests (${\alpha}=0.05$) were used to evaluate WTK and WL. CS specimens were subjected to 2-way analysis of variance (ANOVA) and the Tukey post hoc test (${\alpha}=0.05$), and KH was evaluated by one-way ANOVA, the Holm-Sidak post hoc test (${\alpha}=0.05$), and the t-test for independent samples (${\alpha}=0.05$). Results: The bleaching agent increased the WTK of Maxxion R, but did not affect the WL of any GICs. It had various effects on the CS, KHN, surface topography, and the chemical element distribution of the GICs. Conclusions: The bleaching agent with 37% $H_2O_2$ affected the mechanical and surface properties of GICs. The extent of the changes seemed to be dependent on exposure time and cement composition.

• Korean Institute of Interior Design Journal
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• v.18 no.6
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• pp.36-43
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• 2009

Structure is one of the most important components in designing chairs, since a chair should support the weight of users and make them feel comfortable. However, previous studies have focused on examining the materials and the techniques of processing of chairs, but less on studying the structures to facilitate human friendly use enough to influence the change of the current chair design. The purpose of this study is to analyze the composition element in structure of the chair design specifically from 2000 to 2008 the fundamentals to achieve quality chair design. This study examined 386 chairs which the most reputable furniture fair, the Milan International Furniture Fair exhibited from 2000 to 2008. 386 chairs were chosen from 72 companies which passed the popularity and ranks. 24 Components of the structure of chairs were used to annalize the 386 chairs. The structural types of chair design included 51 kinds. Among them, the most representative types appeared to be 5 kinds. Particularly, the single structure chair was comprised of 25%, its productivity has increased steadily since 2004 which indicated that the structure of chair has become simplified. According to the components of chair, classified structure types were analyzed into (1) a single structure consisting of one component, (2) a simple structure with two components, (3) a complex structure with three components, and (4) a multiple structure with four components. The majority of chair types followed the order of the single structure, simple structure, complex structure, and multiple structure. The results of the analysis on the structure of chairs indicated that the structure of chairs has been changed toward single type No. 24 and simple type No. 6+13.

• Transactions of Materials Processing
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• v.31 no.6
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• pp.376-383
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• 2022

The potential damage region of a WC-Co cemented carbide die is investigated for cold forging process of a wheel-nut by numerical simulation with its chemical composition considered. Numerical simulation is utilized to calculate internal stress, especially for the WC-Co die, during the forging process. Finite element model is established, in which the elasto-plastic properties are applied to the work-piece of bulk steel, and elastic properties are considered for the lower die insert of the WC-Co alloy. This stress analysis enables to distinguish the potential damage regions of the WC-Co die. The regions from calculation are comparatively analyzed along with the crack area observed in the die after repetitive manufacturing. Effect of chemical composition of the WC-Co is also evaluated on characteristics of potential damage region of the die with variance of mechanical properties considered. Derived from Mohr-Coulomb fracture model, furthermore, a new stress index is presented and used for die stress analysis. This index inherently considers hydrostatic pressure and is then capable of deducing wide range of its distribution for representing stress state by modification of its parameter implying pressure sensitivity.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2004.08a
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• pp.277-284
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• 2004

Low carbon steels containing Si of up to $1.2\;wt\%$ were oxidized in air at 1373 K and 1523 K, i.e. below and above the eutectic temperature of FeO and $Fe_2SiO_4$. The influence of a impurity element, S on behavior of scale formation during oxidation was investigated by using $M\"{o}chssbauer$ spectroscopy and EDS. This allowed establishment of an interface oxidation model of Si-added steel depending on temperature and an impurity element. A compound of FeO and FeS was formed in the scale/matrix interface of low carbon steels containing S of up to $0.03\;wt\%$ oxidized above 1213 K of the eutectic temperature. This was flat formed between $Fe_2SiO_4$ nodules along the scale/matrix interface without selective oxidation. It is due to low viscosity and high wettability of the compound of FeO and FeS in liquid. Conventional metallographic examinations revealed that roughness of the scale/matrix interface in Si-added steels became flat as the content of S increased. It was independent of oxidizing temperature and Si content. Effects of oxidizing temperature and an impurity element content on descaling characteristics in Si-added steels were evaluated by using a hydraulic descaling simulator. Good descaling characteristics was attributable to this flatness of the scale/matrix interface.

• The Journal of the Korea institute of electronic communication sciences
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• v.11 no.11
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• pp.1039-1046
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• 2016

To study a habit and life patten of a wild animal, this paper do a research on the location tracing system of wild animal by yagi-antenna low pass filter, angle tracking technology. Commonly, VHF Radio Telemetry is used for the location tracing system of wild animal. Considering movement, Previous yagi-antenna has 4-element and has advantage of portability but the other advantages are small and preference is weak. To make the advantage of yagi-antenna higher than previous one, Supposed technology adapt to 6-element and make out Narrow space yagi-antenna technology. Also, It supposes that AOA (:Angle of arrival) technology is applied to detecting technology for a close direction from received signal. Based on this study suggest that position tracing technology is so as to figure out a life patten and habit of a wild animal which live in a certain area.

• Journal of the Korea Fashion and Costume Design Association
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• v.21 no.4
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• pp.27-42
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• 2019

This paper tried a detailed approach to identify the correlation among basic elements that influenced the change of forms of the Po. To this end, the subjects were limited to the clothing from the 15th to the 18th century, which was found in the tombs of the period of Pyeonbokpo. The total number of excavated artifacts measured directly is 6 and other correctly described excavated artifacts for a total of 54 items. Per period and element, the types of collars and Seop were presented by classifying collars in 4 types, and Seop in 3 types. On the basis of the classification, the relics selected in this paper were analyzed considering the appearance, period, and rate per type of each element. The type and the change of forms of each element per period, with the focus on the appearance, were identified and the factors influencing the change of forms per element and the correlation between such factors were investigated. The representative type in the first period included dual collars, dual Seop and the representative type in the second period was characterized by a shawl collar and a dual Seop joining the pieces. The representative type in the third period was characterized by round collars and a short Seop. The elements determining the forms of Po, including collars and Seop, had a correlation to the lapse of time and had been systematically influencing each other. Furthermore, the overall change of form was caused due to the social functions as well as the supplementary function of keeping balance among the elements and accordingly, the change of forms was think characterized per period.

• Fashion & Textile Research Journal
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• v.10 no.6
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• pp.1014-1022
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• 2008

This study focuses on practical appliance of color therapy to skin care. After visiting the notion of color therapy and skin care, this study considers the ideas and background theories for diagnosis of constitution and skin. Cosmic duals force five element theory developed in China was the first introduction; Ayurvedic medicine and seven chakra notion are examined. Cosmic duals force five element theory, an idea describing the composition and movement rule of the cosmic components, adopted five colors(white, yellow, red, blue, and black) for cure purposes. In future, mental effect of the color is examined in the latter part of this study. The practice of the color therapy assigns solarized cream treatment and photo therapy, simultaneously proposes the use of color therapy to the skin care. For the diagnosis of the constitution, cosmic duals force five element theory and ayurvedic medicine are followed in a sequence. Cosmic duals force five element theory introduces five colors. Constitution medicine considers four types, ayurvedic medicine adopts three types, and seven colors are mentioned as chakra colors. Such a variations lead to possible disagreement on constitution analysis and driven colors. This study adopts the above methodologies for selecting potential color therapy for skin care. Adopt of selected cases are purely a part of the proposal. Initially, examined theories serve as a pilot for selecting a representative hypothesis. Followed selection of constitution and matched color for the use of the skin care are the scope of this study. In summary, background methodologies are implemented for the calculation of color therapy.