• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.11a
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• pp.537-540
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• 2010

An Enhanced Huels Type Plasma Torch that generates over $5000^{\circ}C$ plasma arc flow is the core equipment of arc-jet wind tunnel. It is applied to the high-tech areas such as a new materials development and eco-friendly industry. Although the Enhanced Huels Type Plasma Torch produce uniform flow of high purity, its complicated structure and operating condition makes the commercialization of it to be difficult. The 400kW arc-jet generator using the enhanced Huels type plasma torch was tested. The result of this study showed that the torch was operated in the range of 280~320 A and 250~1350 V.

• Smart Structures and Systems
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• v.25 no.6
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• pp.751-764
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• 2020

Real-time monitoring of stiffness and strength in cement based system has received significant attention in past few decades owing to the development of advanced techniques. Also, use of environment friendly supplementary cementitious materials (SCM) in cement, though gaining huge interest, severely affect the strength gain especially in early ages. Continuous monitoring of strength- and stiffness- gain using an efficient technique will systematically facilitate to choose the suitable time of removal of formwork for structures made with SCM incorporated concrete. This paper presents a technique for monitoring the strength and stiffness evolution in hydrating fly ash blended cement systems using electro-mechanical impedance (EMI) based technique. It is important to observe that the slower pozzolanic reactivity of fly ash blended cement systems could be effectively tracked using the evolution of equivalent local stiffness of the hydrating medium. Strength prediction models are proposed for estimating the strength and stiffness of the fly ash cement system, where curing age (in terms of hours/days) and the percentage replacement of cement by fly ash are the parameters. Evaluation of strength as obtained from EMI characteristics is validated with the results from destructive compression test and also compared with the same obtained from commonly used ultrasonic wave velocity (UPV). Statistical error indices indicate that the EMI technique is capable of predicting the strength of fly ash blended cement system more accurate than that from UPV. Further, the correlations between stiffness- and strength- gain over the time of hydration are also established. From the study, it is found that EMI based method can be effectively used for monitoring of strength gain in the fly ash incorporated cement system during hardening.

• Journal of Korea Port Economic Association
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• v.25 no.4
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• pp.251-280
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• 2009

The value of Environment is so high and important that no one can estimate it correctly. In the area of Logistics, Environment protection is very important and keen subject for the present and for the future of this country and people. Environmental logistics, similarly used as Green logistics, means the protection of Nature and Environment and reduces all kinds of factors and behaviors that may destroy and deteriorate current Environment. It also include the preservation of Nature and sustainable development. Environmental logistics aims to save natural resources and to promote reuse of all kinds of materials and to increase the utilization of Environment friendly substitute goods. In this paper the concept and characteristics of Environmental logistics were summarized and described. Also the main previous studies were surveyed. Some of important cases and experiences which were introduced and applied in major countries such as Japan, Hongkong, USA and the case of PHILIPS were summarized and analyzed. With these cases and analysis, this paper suggested some alternatives and countermeasures for the improvement of Environmental logistics in terms of 3 dimensions such as Country, Company and Individual level. And a strategy model for enhancement of the Environmental logistics was suggested and limitations of this paper and future research directions were described.

• Journal of Digital Convergence
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• v.18 no.7
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• pp.383-387
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• 2020

This paper studies the GUI design of motion-sensing game character selection. The game's GUI plays a role in transferring information in human-computer interaction. The purpose of this game player-oriented GUI design is to optimize the human-computer interaction, make the operation more user-friendly, reduce the user's cognitive burden, and better adapt to the user's operation needs. This paper combines examples to compare and analyze these three games from three aspects: text, color and form. In the existing motion-sensing game games, the character selection GUI has a design feature of high recognition and strong visibility. Finally, suggestions for GUI design of motion-sensing game games are given. It is hoped that in the future, reference materials will be provided for the GUI design of experience game character selection.

• Korean Journal of Construction Engineering and Management
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• v.9 no.4
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• pp.131-139
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• 2008

Now, one of the greatest concerns at home and abroad is eco-friendly construction. Above all, the reduce and recycle of the construction waste may be one of the most important things. The construction waste has been produced most at demolition phase, but the research into that area has not being to make nearly within the country. Recently, as the government have realized the importance of that area, they are making research to improve traditional demolition methods. Also, they are preparing to make a raw to enforce deconstruction during demolition phase. This research has analyzed the problems and waste types which produced during the demolition works by surveying in site. Until now, in the interior, the right quantity basis has not been suggested, because of the absence of any methods to estimate it accurately. Therefore, this study has compared and analyzed owner's ordering quantity, drawing analysis quantity with measuring the waste to produced at site during demolition works, this research results are expected to be the important materials for future research into the construction waste area.

• Journal of Environmental Health Sciences
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• v.35 no.3
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• pp.226-234
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• 2009

The main objective of this study was to evaluate the effects on shape and size, compressive strength, water absorption and heavy metals leaching with various weight mixing ratios in waste ash brick products using waste recycling MSWI(Municipal Solid Waste Incinerator) bottom ash, steel slag and waste building material. The manufacturing processes for the waste ash brick consist of screening, mixing, conveyor transmission, compaction.forming, and curing steps of raw materials. The weight mixing ratios of steel slag around bottom ash were adjusted within the ranges of 10% to 30%. The reported results show that the width and thickness of the manufactured waste ash brick could be satisfied with $90{\pm}2mm\;and\;57{\pm}2mm$, respectively which are K.S. standards of products qualities. And in case of length, only 20-Ba50Ss30, 20-Ba60Wb20 and 20-Ba50Wb30 for the mixing ratios could be satisfied with $190{\pm}2mm$ that is K.S. standards of products quality. The compressive strength and water absorption for 20-Ba50Ss30 and 20-Ba70Wb10 were over $8N/mm^2$ and below 15% respectively that are K.S. standards of manufactured waste ash brick. The results of tests for the heavy metals leaching in the all manufactured waste ash bricks are also passed to the wastes management regulations. The cost analysis of 20-Ba50Ss30 is evaluated. The manufacturing cost is evaluated 34.3 won/brick with 8 hours and 20tons of raw material per day. Incinerators with problems in bottom ash disposal can therefore derive significant benefits from the application of waste ash brick production.

• Journal of the Korean Recycled Construction Resources Institute
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• v.8 no.2
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• pp.204-211
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• 2020

Poly-Lactic Acid(PLA) fiber is an eco-friendly material and is biodegradable, so it can be utilized for manufacturing porous construction materia ls with interna l pore connection. In this study, domestic PLA fiber products(0.5mm india meter, 1.0mm in length, 10mm in length) were tested for melting at high temperatures and high alkality, and they were incorporated with FA-based geopolymer. Compressive strength was obtained through high temperature curing and alkali activator, however the complete melting of the PLA fiber was not ensured. The previous study handling PLA fiber with 0.003mm in diameter was completely dissolved, but 0.5mm and 1.0mm in diameter showed 42.5% and 33.3% of dissolution ratio, respectively. In addition, the increasing fiber volume led floating fibers during curing, which had a negative effect on its workability and solubility. Although the properties of PLA fiber may vary depending on the raw materials and production conditions, PLA fiber with 0.1mm or less diameter is recommended for porous construction material.

• Journal of the Korean Society of Clothing and Textiles
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• v.31 no.1 s.160
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• pp.21-32
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• 2007

The purpose of this study is to establish the idea of sustainable slow design by analyzing literatures and preceding cases, based on the external elements of a design including forms, the methods of expression, materials and colors. This study reviewed the previous literature of books and pictures related to the research for case studies and content analysis. fashion books, magazines, and web-sites published from 2000 to 2005 were analyzed for this research. The sustainable slow design trends in fashion can be summarized as follow. The first is a timeless style which has sustain ability in design independently of the versatile fads and relies on functionality, serving the purpose of design. One of the examples is both clothes designed by Burberry and suits by Chanel. The second is a hand-touch style which the more time for outputs can be positively tolerated, in favor on eco-friendly design through the techniques of manual arts. The third is a renewable design which the combined values of design with reuse and renewal result in recreation of past ecology as shown in the technique of designs by mix & match. The forth is a transformable design which features the multi-purpose and multi-forms, eventually extending the lift cycle of products. As a result of analysis of the four designs above, it can be inferred that the representation of past styles, the mixture of old design with new design, the appropriate combination of conventional fabrics with advanced ones, the ecological trends of sports look was emerging.

• Transactions of the Korean Society of Automotive Engineers
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• v.14 no.5
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• pp.39-46
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• 2006

The fuel cell is one of promising environment-friendly energy sources for the next generation. The bipolar plate is a major component of the PEM fuel cell stack, which takes a large portion of stack cost. In this study, as alternative materials for bipolar plate of PEM fuel cells, graphite composites were fabricated by compression molding. Graphite particles mixed with epoxy resin were used as the main substance to provide electric conductivity To achieve desired electrical properties, specimens made with different mixing ratio, processing pressure and temperature were tested. To increase mechanical strength, one or two layers of woven carbon fabric were added to the graphite and resin composite. Thus, the composite material was consisted of three phases: graphite particles, carbon fabric, and epoxy resin. By increasing mixing ratio of graphite, fabricated pressure and process temperature, the electric conductivity of the composite was improved. The results of tensile test showed that the tensile strength of the two-phase graphite composite was about 4MPa, and that of three-phase composite was increased to 57MPa. As surface properties, contact an91e and surface roughness were tested. Graphite composites showed contact angles higher than $90^{\circ}$, which mean low surface energy. The average surface roughness of the composite specimens was $0.96{\mu}m$.

• Korean Institute of Interior Design Journal
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• v.21 no.5
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• pp.3-11
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• 2012

The first visual contact in architecture happens in surface, and it could be significant object as well as the starting point to recognize the essence and perceive the buildings. Architecture surface could not get out of the restriction of structures and materials that support buildings for a long time in the past. Architecture surface in the past should fulfill the structural role to form are appearance of buildings and support buildings at the same time, so it was difficult to get out of logic for material and thickness of walls, arrangements and sizes of windows. However, since the modern age, architecture surface came to be freer according to the development of building technology, and development of technology changes shows tendencies to express role of new design factor as an architectural element emphasized expression and autonomy,s which was escaped from the subordinate relationship that the surface of building must do the structural function. In this study, it would be examined the expressive characteristics of various epidermis that are expressed in architecture of Herzog & de Meuron since the end of 20thcentury focused on comprehended and analyzed results of changes and characteristics of contemporary society. Through this, it would be comprehended the epidermis of architecture that has particular character expressed in modern buildings of Herzog & de Meuron, and it would be composed a certain linkage between this and characteristics of contemporary society and it would be investigated that the establishing process of inner spaces. Identification through case analysis for this would perform a role of catalyst for the new possibility and development of contemporary architecture's surface expression in the future.