• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.11a
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• pp.179-179
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• 2009

For the deposition of the semiconductor nanocrystals or quantum dots, it is required to have the substrates with smooth surface roughness. Slot-die coating method wad adopted and optimized varying the processing parameters like coating speed, gap distance, solution concentration, etc to get the smooth coated films on flexible substrates. The coating speed in slot-die method was varied from 1 m/min to 2.5 m/min focusing especially on its industrial usage. The gap distance between the substrate surface and slot-die lip was changed also to control mainly the thickness of coated films.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.11 no.2
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• pp.9-16
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• 2002

The machinability of Ti-6Al-4V titanium alloy and tool wear behavior in machining of Ti-6Al-4V titanium alloy was studied to understand the machining characteristics. This material is one of the strong candidate materials in present and future aerospace or medical applications. Recently, their usage has already been broaden to everybody's commercial applications such as golf heads, finger rings and many decorative items. To anticipate the general use of this material and development of the titanium alloys in domestic facilities, the review and the study of the machining parameters for those alloys are necessary. This study is concentrated to the machining parameters of the Ti-6A1-4V alloy due to their dominant position in the production of titanium alloys.

• The Journal of Society for e-Business Studies
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• v.8 no.1
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• pp.121-139
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• 2003

Currently, it is not popular to use the STEP based product information in the construction drawing files, in spite of the importance and possibility of using various product data in drawing files on the CALS/EC environment. This paper aims to demonstrate a construction drawing information management system based on ISO 10303/STEP. To achieve this aim, the authors have analyzed the current construction drawing information classification hierarchy widely used for domestic and international, and examined the material data connection mechanism within CAD drawing data, and finally investigated the management systems for construction documentations and drawings in a public companies. Therefore, the expected benefit of the proposed system is that STEP drawing information management will be done standardization and the information of STEP construction drawing can be managed, shared and supported design business through materials data connection.

• Korean Institute of Interior Design Journal
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• v.14 no.2 s.49
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• pp.55-62
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• 2005

In modern days when architectural materials have grave impacts on overall design expression, materials for architecture, modern architecture into the service facility for business, education, religion, cultural assembly and residence, and evaluates each finishing material mainly used in exterior, lobbies and entrances of the building since the 1970's. When being applied social images into firstly selected materials, the scopes for material selection will be more narrowed down in more practical way. High tensity materials are suitable for public and active space and low tensity are for private and static area. This principle enables us to use architectural materials as one of the important elements which express the whole characteristics of the area.

• Journal of Applied Reliability
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• v.11 no.4
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• pp.357-369
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• 2011

Eco-robot for collecting recycling products is the machine which collects non-industrial wastes such as cans, PET bottles and etc. to reuse them as recycling resources. This eco-robot is operated in the condition that it should compress and hold various products without knowing their geometric shapes and material properties. For this reason reliability problems like malfunction or failure. comes to emerge, but the reliability test conditions to assess its performance and durability have not been founded yet. Therefore in this research failure mechanism of the eco-robot was analyzed and life test equipment which can reproduce actual usage conditions was developed. The compression levels in the life test were determined by measuring the crushing force acting on test products and Furthermore the test specimens which have equivalent shape and material properties with those of cans and PET bottles were proposed by simulating the deformation characteristics so that the actual compression conditions were set up in the test.

• Journal of environmental and Sanitary engineering
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• v.15 no.2
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• pp.102-111
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• 2000

As IR-sensor for detecting pollution material, the iron silicide has a fit band gap, high physicochemical stability at high temperature and good acid resistance. The growing film was formed with the Fe-Si bond and the organic compound because plasma resolved the injected precursors into various active species. In the Raman scattering spectrum, the Fe-Si vibration mode showed at 250 {TEX}$cm^{-1}${/TEX}. The FT-IR peak indicated that the various organic compounds were deposited on the films. The iron silicide was epitaxially grown to β-phase by the high energy of plasma. The lattice structure of films had [220]/[202] and [115]. The thickness of the films increased with the flow rate of silane. But rf-power increased with decreasing the thickness. The optical gap energy and the band gap were shown about 3.8 eV and 1.182∼1.194 eV. The band gap linearly increased and the formula was below: {TEX}$E_g^{dir}${/TEX}= 8.611×{TEX}$10^{-3}N_{D}${/TEX}＋1.1775

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.214-214
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• 2006

The huge amounts of wastes were produced nowadays. Among the solid waste stream, the waste plastic portion is about 20 % in weight, over 50 % in volume. But the most of waste plastics were incinerated or land filled. Only a bit of waste plastics were recycled and reused. On the view point of current energy crisis, this will be an extravagance of beneficial resource. So we should consider the waste plastics as a beneficial raw material. Also need to develop the field of reusing and recycling of post-consumed plastic. In this context, present paper describes the methodology for enhancing or improving the specific properties by way of using inorganic filler waste. Also develop the product from these post-consumed plastic.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1999.04a
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• pp.110-120
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• 1999

Topology optimization is used for determining the best layout of structural components to achieve predetermined performance goals. In the present study, we consider that the objective function is to maximize the natural frequency of the structure for a designated mode and the constraint function is to constrain a total material usage. In this paper, using a topology optimization technique based on the homogenized material and the chessboard prevention strategy, we obtain the optimal layout and the reinforcement of an elastic structure. Several examples are presented to show the ability of the topology optimization technique used in this paper to deal with an optimal layout problem for a free vibration structure.

• KCI Concrete Journal
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• v.14 no.4
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• pp.161-169
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• 2002

The mechanical properties of fiber reinforced porous concrete for use as a planting material were investigated in this study. Changes in physical and mechanical properties, subsequent to the addition of carbon fiber and silica fume, were studied. The effects of recycled aggregate were also evaluated. The applicability as planting work concrete material was also assessed. The results showed that there were no remarkable changes in the void and strength characteristics following the increase in proportion of recycled aggregate. Also, the mixture with 10% silica fume was found to be the most effective for strength enforcement. The highest flexural strength was obtained when the carbon fiber was added with $3\%$. It was also noticed that PAN-derived carbon fiber was superior to Pitch-derived ones in view of strength. The evaluation of its usage for vegetation showed that the growth of plants was directly affected by the existence of covering soil, in case of having the similar size of aggregate and void.

• Journal of KIBIM
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• v.2 no.2
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• pp.17-26
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• 2012

This paper presents the results of a theoretical energy analysis of a research test bed called the Zero Net Energy Test House (ZNETH) in Omaha, Nebraska in U.S.A. The ZNETH project is being designed and built with the goal of consuming a negligible amount of energy by offsetting remaining usage after energy conservation. The theoretically consumed and generated energy levels were analyzed using energy modeling software programs. By integrating a highly graphical and intuitive analysis with a Building Information Model(BIM) of the house, this investigation introduces strategies to include sustainable materials and systems to predict energy generation with a case study of ZNETH. In addition, this paper introduces parametric analyses for better envelope design and construction material selection by analyzing simulated energy consumption with various parametric inputs, e.g., material types, location, and size. It was found that the current design of ZNETH does not meet its goal of zero net energy. Sugeestions are presented to assist ZHETH in meeting its net zero energy goal.