• Transactions on Electrical and Electronic Materials
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• v.17 no.5
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• pp.239-251
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• 2016

The potential of nanocomposites have been drawing the intention of the researchers from energy storage to electrical insulation applications. Nanocomposites are known to improve dielectric properties, such as the increase in dielectric breakdown strength, suppressing the partial discharge (PD) as well as space charge, and prolonging the treeing, etc. In this review, different theories have been established to explain the reactions at the interaction zone of polymer matrix and nanofiller; the characterization methods of nanocomposites are also presented. Furthermore, the remarkable findings in the fields of epoxy, cross-linked polyethylene (XLPE), polypropylene and polyvinyl chloride (PVC) nanocomposites are reviewed. In this study, it was observed that there is lack of comparison between results of lab scale specimens and actual field aged cables. Also, non-standardization of the preparation methods and processing parameters lead to changes in the polymer structure and its surface degradation. However, on the positive side, recent attempt of 250 kV XLPE nanocomposite HVDC cables in service may deliver a promising performance in the coming years. Moreover, materials such as self-healing polymer nanocomposites may emerge as substitutes to traditional insulations.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.12
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• pp.1159-1165
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• 2005

New conductor is developed by using high strength nonmagnetic steel(NM) wire as the core of overhead conductor This conductor is called ACNR overhead conductor(Aluminum Conductor Nonmagnetic Steel Reinforced). Formed by the combination of aluminum alloy wire and high strength nonmagnetic steel wire, it has about the same weight and diameter as conventional ACSR overhead conductor. To enhance properties beneficial in an electrical and mechanical conductor during the Process of high strength nonmagnetic steel wire, we made a large number of improvements and modifications in the working process, aluminum cladded method, and other process. ACNR overhead conductor, we successfully developed, has mechanical and electrical properties as good as or even better than conventional galvanized wire. Microstructure of raw material NM wire was austenite and then deformed martensite after drawing process. Strength at room temperature is about $180kgf/mm^2\~200kgf/mm^2$. The conductivity at 0.78 mm thickness of Aluminum cladded M wire is about $7\%$ IACS higher than $20\%$IACS of HC wire used as core of commercial ACSR overhead conductor. The corrosion resistance is about 3 times higher than that of HC wire.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.05a
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• pp.829-832
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• 2000

This paper describes a research work of developing a computer-aided design of product with bending and piercing for progressive working. An approach to the CAD system is based on the knowledge-based rules. Knowledge fur the CAD system is formulated from plasticity theories, experimental results and the empirical knowledge of field experts. The system has been written in AutoLISP on the AutoCAD with a personal computer and is composed of three main modules, which are input and shape treatment, flat pattern layout and strip layout module. Based on knowledge-based rules, the system is designed by considering several factors, such as radius and angle of bend, material and thickness of product, complexities of blank geometry and punch profile, bending sequence, and availability of press. Strip layout drawing automatically generated by piercing with punch profiles divided into for external area is simulated in 3-D graphic forms, including bending sequences for the product with piercing and bending. Results obtained using the modules enable the manufacturer of electronic products to be more efficient in this field.

• JSTS:Journal of Semiconductor Technology and Science
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• v.16 no.6
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• pp.854-859
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• 2016

Recently, GeSn is drawing great deal of interests as one of the candidates for group-IV-driven optical interconnect for integration with the Si complementary metal-oxide-semiconductor (CMOS) owing to its pseudo-direct band structure and high electron and hole mobilities. However, the large lattice mismatch between GeSn and Si as well as the Sn segregation have been considered to be issues in preparing GeSn on Si. In this work, we deposit the GeSn films on Si by DC magnetron sputtering at a low temperature of $250^{\circ}C$ and characterize the thin films. To reduce the stresses by GeSn onto Si, Ge buffer deposited under different processing conditions were inserted between Si and GeSn. As the result, polycrystalline GeSn domains with Sn atomic fraction of 6.51% on Si were successfully obtained and it has been demonstrated that the Ge buffer layer deposited at a higher sputtering power can relax the stress induced by the large lattice mismatch between Si substrate and GeSn thin films.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07a
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• pp.597-600
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• 2003

Bi-2223/Ag HTS wires have been fabricated by the PIT(powder in tube)process. Intermediate annealing was carried out to increase the homogenization and uniformity of the superconducting filaments embedded in the silver matrix during the deformation process that is important to sustain the engineering critical current density in long superconducting wire. Intermediate annealing act to release the deformation hardening of the superconducting wires during drawing process. Rolling parameters were investigated to roll the superconducting tapes with uniform thickness, width and winding tensions. Critical current of 60 m long superconducting tapes was measured 54.3 A continuously after final sintering heat treatment. The phase analysis of Bi-2223/Ag superconducting tapes are examined by the XRD.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.05b
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• pp.119-122
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• 2003

The purpose of this study is to find problems of "Electricity equipmentand" and "Electricity practic II" tectbook applied in 6th Technical High School Curriculum and to make direction of "Power equipment II" textbook applied in 7th Technical High School Curriculum. The method of this study is questionnaire survey. 120 teachers of 40 schools were selected by cluster sampling method. The main findings of this study are as follow. 1) We should make the composition of textbook easy. 2)The illustration, photograph and drawing of textbook are fitted well. 3) "power equipment II" textbook applied in 7th Technical High School Curriculum would contented follows : lighting equipment, elevator equipment, broadcasting equipment, interphone equipment.

• Journal of the military operations research society of Korea
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• v.18 no.2
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• pp.1-22
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• 1992

Computer-aided logistics support system is recognized an essential system to reduce supply and maintenance cost, and to improve readiness of weapon system or operationable composite machines. According to these trends, this paper focuses on the design scheme and the computerization strategy of information management system for Integrated Logistics Support (ILS) work. Suggested system. LAMIS(Logistics support Analysis Management Information System) is a total system that composed of Logistics Support Analysis Management information system (LSAM), Configuration Management Information System (CMIS), Maintenance Management Information System (MMIS), Project Management System (PMS) and Information Retrival System(IRS) etc. Also, LAMIS is a computerized tool that improves current supply and maintenance support program, that attempts to reliable requirment analysis of logistics support elements, and that supports to use the existing technical specification of similar one when weapon system acquisition project is started newly. When LAMIS implication is completed, it can be applied to logistics support of defense or commercial site. Straightway, LAMIS will be enhanced with computer - aided design system, engineering drawing system, interactive electronic technical manual system, electronic data interchange system, and three dimensional simulation system to weapon system configuration. When that is done, LAMIS is CALS system.

• Journal of the Korea Society of Computer and Information
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• v.21 no.11
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• pp.93-101
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• 2016

In this paper, we propose a new model, assembled ERP, to analyze the reason why the small and medium sized companies have a low ERP implementation rate and to solve this. As a result of our analysis, the high initial costs and time required for implementing ERP keep such companies from implementing it as they have relatively limited resources. The assembled ERP model, however, reduces the scale of ERP by developing the ERP for the unique business of each and connecting a few 3rd-Party applications as a module to make ERP for common work. Also it enables easier data utilization by drawing up an API list that connects the 3rd-Party applications to the developed ERP when the user lacks knowledge in the master data of the 3rd-Party applications. Therefore it lets the small and medium sized companies introduce the ERP more easily by reducing the costs for ERP implementation and user training.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.1
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• pp.317-323
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• 2006

The objective of this study is to test and modify the gantry travel mechanism of an ALV(automated lifting vehicle) as a main technology of development of ALV. For the purpose of the improvement of container terminal productivity, this study performed to develop the ALV as a part of R&D. In order to verify the design data and detect the errors of detailed drawings, we performed the various limited weight test under load and unload conditions. Through the reflect of final drawing based on the this test, we could use to produce the more complete vehicle.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.408-409
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• 2007

Ferrule function have connect Optical Communication Cable. But Ferrule have important role that is decided transmission efficiency and information quality. Key-point of detailed drawing of ferrule is Anti-Reflection. In the study Broadband Anti-Reflection coating Film was design for ferrule of optical connector and deposited in low temperature by Ion-Assisted Deposition system. Optical thin film materials($Ta_2O_5$, $SiO_2$) were manufactured Index and Film thickness. $Ta_2O_5$ index is 2.123 ~ 2.125 and $SiO_2$ is 1.44 ~ 1.442. Reflection Loss of film deposited on Ferrule is 30.1[dB].