• 한국결정학회:학술대회논문집
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• 한국결정학회 2003년도 춘계학술연구발표회
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• pp.6-6
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• 2003

Highly crystalline 5H-polytypic form of sp3-bonded boron nitride (BN) was grown by pulsed-laser-vaporization of BN, where synchronous reactive-plasma packets assisted the crystal growth in the vapor phase. The structure of the product crystallites (˙5 micrometers) was confirmed by using transmission electron diffraction and electron energy loss spectroscopy. This material proved to have a sharp and dominant band at 225 nm by cathode luminescence at room temperatures and corresponding monochromatic images revealed that they uniformly emitted the ultraviolet light. Considering that cubic BN has already been doped as p- and n- type semiconductors, this material may be applied to the light-emitting devices working at almost the deepest limit of the UV region that is functional without vacuum.

• 한국안전학회지
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• 제23권6호
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• pp.1-6
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• 2008

Machine operator and quality are affected by chip during cutting process to product machine parts. This paper presents a study of the influence of cutting conditions on the surface roughness obtained by turning using Taguchi method for safety of turning operator. In the machining of titanium alloy, high cutting temperature and strong chemical affinity between the tool and the work material are generated because of its low thermal conductivity and chemical reactivity. Therefore titanium alloys are known as difficult-to materials. An orthogonal array, the signal-to-noise ratio, the analysis of variance are employed to investigate the cutting characteristics of implant material bars using tungsten carbide cutting tools of throwaway type. Also Experimental results by orthogonal array are compared with optimal condition to evaluate advanced reliability. Required simulations and experiments are performed, and the results are investigated.

• 한국포장학회지
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• 제8권2호
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• pp.49-59
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• 2002

플라스틱 포장재의 주요 기능은 식품을 수송, 보관과정에서 안전하게 보존하는 것이다. 식품과 플라스틱 포장재간의 반응은 식품의 품질과 안전성 문제에 있어서 상당한 이슈가 되고 있는데 이는 주로 플라스틱에 남아있는 잔류용제, 단량체, 첨가물 등이 식품으로 전이되는 문제들이다. 플라스틱 포장재에 항산화제를 첨가하는 것은 필름의 열화는 물론 포장된 식품, 특히 유지가 많은 제품의 산화를 막을 수 있다. 현재 BHT와 같은 항산화제를 플라스틱 포장재에 적용하는 것이 상업화되어 제품의 유통기간을 연장시키는 방법으로 사용되고 있다. Alpha tocopherol은 가장 중요한 자유기 제거제의 하나로 생물 시스템에는 잘 알려져 있는데 이것을 포장재에 사용함으로써 생산자와 소비자 모두 매우 긍정적인 반응을 보이고 있다. Alpha tocopherol은 폴리올레핀계 레진에 적용되어 BHT를 대체하고 있다. 이 연구는 포장재와 제품간의 증발-흡착 메카니즘을 이용한 항산화제의 효과와 그 적용, 그리고 이러한 메카니즘을 예측할 수 있는 분석기법을 설명하였다.

• 한국결정성장학회지
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• 제27권4호
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• pp.212-219
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• 2017

앞으로 다가올 감성이 지배하는 '하이터치(High-Touch)'의 시대에 걸맞은 사람이 되기 위해서는 6가지 능력이 중시되는데 디자인, 스토리, 조화, 공감, 놀이, 의미가 있으며 이 중에서 디자인과의 조화를 가장 중요한 능력으로 꼽았다. 모든 비즈니스의 기본요소라고 볼 수 있는 디자인은 논리적이고 객관화된 정보와 지식을 바탕으로 만들어진 현대의 디자인 관으로는 직관적이고 감성적인 앞으로의 시대 흐름에 발맞추기 힘들 것이다. 본 논문은 1차적 관점의 디자인 소재 중요성과 함께 심도 있는 Color, Material, Finishing(CMF) 이해와 차별화 전략을 세워 소비자가 느끼는 감성인지요소와 제품의 표면처리디자인 적용을 통한 대품질, 매력품질, 감동품질을 만족시키는 감성 표면처리디자인의 체계화 및 표준화를 제시하였다. 제품에 적용되어지는 부품 유형별 CMF 차별화 전략 방향 설정에 따라 구현가능성 차별성 신표면처리특성 효율성을 고려하여 시각적 표면처리 샘플로 구현하였다. 이를 통해 향후 실질적으로 제품 개발 시 IT 및 전자제품 분야와 그 이상의 분야에서 디자이너, CMF 디자이너, 표면처리전문가, 엔지니어 등 실무 환경에서의 대상제품, 부품유형, 적용소재, 적용표면처리, 표면컬러, 표면질감, 구현하고자하는 느낌 등 통합적 요소들을 이해하고 공유할 수 있는 실무자 소통연계 툴 및 감성 표면처리디자인 전략적 접근 프레임워크로서의 활용이 예상되는 바이다.

• Bulletin of the Korean Chemical Society
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• 제24권5호
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• pp.613-616
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• 2003

Effect on hydrothermal treatment of lamellar vanadium oxides was investigated and the formation of hexagonal and cubic mesophase was found. This lamellar materials were prepared by mixing of cetyltrimethylammonium-bromide and pH-controlled sodium metavanadate solution. Thermal method and UV/O₃treatment were applied to extract organic template. The structure of resulting product was studied by powder X-ray diffraction and transmission electron microscopy (TEM).

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• 제5B권3호
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• pp.207-214
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• 2005

After more than 100 years of development, rotating electric machines are a mature industrial product. Nevertheless, improvements are still possible for specific applications, and it is likely that the major evolution will be promoted by new materials and unconventional structures. Till now, plastic materials are an infrequent choice for the electric machines structural parts, but pioneering applications, such as aeronautical components, let some technological scouting: a low-weight/high-efficiency plastic axial flux motor for a solar flying platform is presented as an example of combined new-material/new-geometry development. The basic design aspects and the prototyping choices are presented and discussed together with the first experimental results.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2003년도 봄 학술발표회 논문집
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• pp.335-336
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• 2003

The synthesis of poly(trimethylene terephthalate) (PTT), whose application is being expanded very rapidly to new apparel and carpet materials, was investigated by melt condensation polymerization using 1,3-propanediol (PDO) and terephthalic acid (TPA). No catalyst was used in the 1st step reaction (esterification), but tetrabutyl titanate(TBT) was used as a polyesterification catalyst ranging from 25 to 75 ppm based on the weight of TPA used in the 2nd step reaction (polyesterification). The molar ratio of PDO to TPA was set as 2.2:1. The effect of reaction conditions on the color and intrinsic viscosity of the final product was investigated. (omitted)

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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• pp.676-678
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• 2004

In order to develop new yellow phosphor that emit efficiently under the 450 - 470 nm excitation range, we have synthesized a $Eu^{2+}$-activated $Sr_3SiO_5$ yellow phosphor and investigated an attempt to develop white LEDs by combining it with a InGaN blue LED chip (460 nm). Two distinct emission bands from the InGaN-based LED and the $Sr_3SiO_5$:Eu phosphor are clearly observed at 460 nm and at 570 nm, respectively. These two emission bands combine to give a spectrum that appears white to the naked eye. Our results showed that InGaN (460 nm chip)-based $Sr_3SiO_5$:Eu exhibits a better luminous efficiency than that of the industrially available product InGaN (460 nm chip)-based YAG:Ce.

• 한국해양공학회지
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• 제21권3호
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• pp.58-64
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• 2007

New artificial fishing reefs are developed using modified sulfur concrete. Modified sulfur concrete, which is made of by-product aggregates and modified sulfur binder, has good properties, including high density, less water absorption, high strength, high salt resistance, and good affinity for living organisms. This paper shows the mechanical properties of modified sulfur concrete and its field tests under the sea. We have found that the pH-neutral materials attach microalgae and seaweed more readily, compared to the pH-high materials.

• 한국가구학회지
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• 제27권1호
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• pp.35-42
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• 2016

With radical increase in one-person households, the consumption market in Korea has also rapidly changed. In line with this movement, customized furniture for sing lecustomershas been recently introduced. Since sleeping more than eight hours a day is needed to maintain a healthy lifestyle, a suitable bed for a comfortable sleep is an essential product for single consumers. In order to respond to this trend, a study was conducted to examine the surface materials of a bed designed for singles. A complete enumeration survey was implemented for beds manufactured by ACEBED Co., Ltd., Simmons-k, Co, Ltd,. Keumsung Bed, Hanssem Co,. Ltd., Hyundai Livart Co,. Ltd,. Emons Furniture Co,. Ltd,. and Borneo International Furniture Co., Ltd. This study helped in the proper selection of surface materials that may be used in the development of furniture for single consumers.