• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.2
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• pp.235-241
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• 2001

A crack with electrically conducting surfaces in a linear electrostrictive ceramic subjected to uniform electric fields is analyzed. Complete forms of electric fields and elastic fields for the crack are derived by using the complex function theory. The linear electromechanical theory predicts overlapping of the traction free crack surfaces. It is shown that the surfaces of the crack are contact near the crack tip. The contact zone size obtained on the basis of the linear dielectric theory for the conducting crack does not depend on the electric fields and depends on only the original crack and the material property for the linear electrostrictive ceramic.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.180-183
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• 2009

Composite bipolar plates offer several advantages of low cost, light weight, and ease of manufacturing compared to traditional graphite plate. However, it is difficult to achieve both high electrical conductivity and high flexural strength. In this study, the hybrid carbons filled epoxy composite bipolar plates were fabricated to test electrical conductivity and flexural properties. Graphite powders were used as the main conducting filler and continuous carbon fiber fabrics were inserted to improve the mechanical properties of the composite. This hybrid composite showed improved in-plane electrical conductivity and flexural property. The moldability of the hybrid composite was also improved comparing to the continuous prepreg composite. This study suggested that the continuous carbon fiber inserted graphite/epoxy composites can be a potential candidate material to overcome the disadvantages of conventional graphite composite or continuous prepreg composite bipolar plates.

• The International Journal of Costume Culture
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• v.12 no.1
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• pp.38-51
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• 2009

The goal of this study is to define the types of the lifestyles of senior consumers and identify the differences in the properties of apparel products and the apparel attitudes. To collect the data for this study, questionnaires for the research were distributed from November 20, 2006 to December 15, 2006 to those over 50 living in Seoul, Pusanand Kyunggi and 302 questionnaires were used for the data analysis. The results of the study are as follows. First, six factors were extracted which were "Pursuit of Self-development", "Pursuit of Active Life", "Pursuit of Material", "Pursuit of Diversity", "Pursuit of Family-oriented" and "Pursuit of Recreational Life" after factor analysis of lifestyles recognized by the senior consumers that participated in this study. Second, the lifestyles of the senior consumers were categorized into "Consumption-oriented Type", "Personal Satisfaction-oriented Type", "Family Weighted Type" and "Recreation-oriented Type." Third, three factors were extracted which were "Symbolical Property", "Functional Property" and "Customer Support Property" after conducting the factor analysis on the properties of apparel products. Fourth, significant differences were shown in apparel properties by the lifestyle types of senior consumers in the symbolical property and the customer support property. The "symbolical property" was shown highest in "recreation-oriented type" and lowest in the "family weighted type." The customer support property was shown highest in the "family weighted type" and lowest in the "recreation-oriented type", showing the opposite result. Fifth, significant differences were shown in apparel attitudes by the lifestyle types of senior consumers in "Fashion Innovativeness", "Apparel Involvement" and "Apparel Necessity." The "fashion innovativeness" was shown highest in the "recreation-oriented type" and lowest in the "family weighted type." The apparel involvement and the necessity for apparel for senior citizens was shown high in the "recreation-oriented type" and this showed that the senior consumers valuing recreation also value fashion, have high apparel involvement and feel the necessity for apparel for senior citizens.

• Proceedings of the Korean Fiber Society Conference
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• 2001.10a
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• pp.17-20
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• 2001

Poly(3,4-ethylenedioxythiophene) (PEDOT), one of the most successful conducting polymers in the market place, has been attracting much interest because of its excellent environmental stability, high conductivity and transparency in thin, oxidized state. Since PEDOT was first synthesized in early 1990s by Jonas et al., many studies on PEDOT have been done to solve its insoluble property in any organic solvents and to extend its application fields[1]. (omitted)

• Journal of the Korean Vacuum Society
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• v.19 no.5
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• pp.326-330
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• 2010

The surface oxidation of magnesium was performed by burning and PEO treatment method. The scanning electron microscopy (SEM), EDS, and I-V characteristics have been applied to the study of the oxidation status. The sample formed by buring method shows weaker corrosion-resistant property than that by PEO method, but this shows more conducting property.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.05a
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• pp.171-172
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• 2015

Recently, it is the global warming phenomenon because of the greenhouse gas exhaustion caused by and the environment problem is serious. And it is the situation where the problem of the exhaustion of resource because of the indiscriminate picking of the that is the raw material of the cement, limestone and natural aggregate are emphasized. In addition, thus the cement reduction amount of use and substitute material research is the urgent actual condition with the gas emission, which here it is generated in conducting compression molding in the building stone manufacturing process performance degradation phenomenon and fire resistance, and problem of the durability. Therefore, in this research, the waste porcelain is applied to the artificial stone and the durability property of the artificial stone according to it tries to be investigated.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.10 no.1
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• pp.117-124
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• 2017

In this paper, we analyzed the technology competitiveness of main competitors based on the patent trend analysis for beauty instruments fields, and drew up the patent reserve strategy and patent portfolio for project related technologies according to technical trends analysis. Using the analysis result of patent portfolio to establish the strategic IP based research and development plans, the patent wall and gap areas are suggested, And, based on the basic information to set up the direction of research and development, we intend to provide objective patent information for the feasibility of conducting research and development tasks and for the avoidance of duplication research.

• Journal of Welding and Joining
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• v.14 no.5
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• pp.49-58
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• 1996

In Korea Gas Corporation, as one of the pipeline repairing methods, damaged pipelines are sometimes treated with a temporally employment of split sleeve. On conducting the repair process, circumferential fillet and longitudinal groove welding usually must be included. For the case of groove welding, a considerable amount of R&D have been carried out related to property changes, while few study on the property change in fillet welding has been conducted. In this paper, so as to confirm the specification of fillet welding in terms of safety and reliability, properties changed by fillet welding were investigated for two welding processes. Qualifying tests such as reviewing macrostructure and nick-break tests were performed according to API 1104 and ASME section IX. In addition, tensile properties and hardness were evaluated according to KS B0841 and BS 4515. The fillet weld prepared by the qualified procedure showed melting depth of 0.8∼1.3mm and heat affected zone of 2.8∼3.4mm length. No crack and lack of penetration were observed. And the results of hardness and nick-break tests satisfied code requirements. The area crossed by fillet and groove welding line was found to have minimal tensile strength.

• Macromolecular Research
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• v.11 no.6
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• pp.481-487
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• 2003

Polypyrrole (PPy) was coated sequentially by chemical and electrochemical methods on a woven fabric, giving rise to a fabric having high electrical conductivity. We investigated the effects of the preparation conditions on the various properties of the resulting fabric. The PPy-coated fabric with optimum properties was obtained when it was prepared sequentially by chemical polymerization at the elevated temperature of 100$^{\circ}C$ under a pressure of 0.9 kgf/$\textrm{cm}^2$ and then electrochemical polymerization with a 3.06 mA/$\textrm{cm}^2$ current density at 25 $^{\circ}C$ for 2 hrs with the separator plate. The surface resistivity of the resulting fabric was as low as 5 Ω/$\square$ .The PPy-coated fabric prepared under the optimum conditions showed practically applicable heat generating property. When electrical power was supplied to the fabric using a commercial battery for a mobile phone (3.6 V, LGLl-AHM), the temperature of the fabric increased very quickly from room temperature to ca. 55 $^{\circ}C$ within 2 min and was maintained for ca. 80 min at that temperature. The heat generating property of the fabric was extremely stable, exhibiting similar behavior over 10 repeated cycles. Therefore, we suggest that the PPy-coated fabric in this study may be practically useful for many applications, including flexible, portable surface-heating elements for medical or other applications.

• Journal of Korea Multimedia Society
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• v.14 no.12
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• pp.1601-1612
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• 2011

In recent years, advanced in digital technologies have created significant changes in the way we reproduce, distribute and market Intellectual Property (IP). DRM for multicast contents is complicated risk, the further technology development and human demand, this approaching is still being researched by the scientist and all by the company which is conducting in piracy management reduced, and every country has national policy to make this consortium to limit piracy properties, based on this paper research development, just only two approaching to reduce piracy in DRM they are Industrial Property (IP) and Copyright. In this paper, we are not only figuring and analyzing about the processes to reduce and limit the piracy and unprotected copy law but also describing about the encryption process, watermarking and digital signature process algorithms. The basic concepts of this encryption process for web-based multicast content in DRM are implemented in Java. We conduct this method is a computerized through web based application system approaching to reduce unprotected copy and piracy. Which is used in DRM for multicast content in every section, by providing a fundamental in information technology development, we believe this research is reliable to prove that is unprotected copy, and piracy can be reduced by protecting with this paradigm.