• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2012년도 추계 학술논문 발표대회
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• pp.211-212
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• 2012

To prevent energy waste in buildings used heat insulator. Heat insulator materials can be classified inorganic and organic. The organic material is due to toxic gas emission, when a fire occurs. And it has lower water resistance. The inorganic material is heavy and worse thermal performance than organic materials. Technologies on energy saving and materials used in curtain walls have progressed with increase of high-rise and large buildings. However, there is little study to explain fire resistance performance of the curtain walls. This study focused on evaluation of the physical properties of light-weight inorganic foam panel for using industrial by-products materials and performance evaluation by mock up test.

• 소성∙가공
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• 제15권9호
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• pp.660-666
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• 2006

This study examined the mechanical properties and bending formability evaluation of spring strip materials(SK5 CSPH, STS 301 CSP-EH, C7701-H). The hardness test and tensile test were performed at room temperature($20^{\circ}C$) for mechanical properties. The U-bending test were carried out at various conditions of punch corner radius(Rp), ratio of punch comer radius/thickness(Rp/t) and ratio of clearance/thickness(Rp/t) and ratio of clearance/thickness(C/t) for bending formability evaluation.

• Tribology and Lubricants
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• 제11권5호
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• pp.26-30
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• 1995

Sliding experiments have been conducted on alumina and silicon carbide ceramics. Wear and friction data of both materials indicate that wear proceeds in two distinct stages. The wear occurs by a relatively mild plastic-grooving process in the initial stage, but eventually gives way to a severe grain pull-out process after a defined period of sliding test. The datails of the transition mechanism are presented. The effects of grain size and second phase particle on the wear transition are also presented.

• 한국자동차공학회논문집
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• 제15권4호
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• pp.171-177
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• 2007

In this paper, an evaluation method of fracture toughness on interface cracks was investigated in friction welded dissimilar materials with interfacial edge cracks. To establish a reasonable strength evaluation method and fracture criterion, it is necessary to analyze stress intensity factor under the load and residual stress condition on friction welded interface between dissimilar materials. The friction welded specimens with an edged crack were prepared for analysis of stress intensity by using the boundary element method (BEM) and the fracture toughness. A quantitative fracture criterion for friction welded STS 304/SM 45C with interface crack is suggested by using stress intensity factor, F and the results of fracture toughness experiment.

• Applied Microscopy
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• 제26권4호
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• pp.479-487
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• 1996

Thin epilayer structures of GaAs/AlAs/InGaAs, grown by Molecular Beam Epitaxy, were investigated by high resolution transmission electron microscopy, Image in the [110] zone axis was taken and compared with the calculated images. The supercell structure which contains GaAs, AlAs and InGaAs layers was designed and was employed in the image calculation with MacTempas computer program. Good agreement was shown between experimental image and a set of calculated images with varying defocus and sample thickness.

• 한국산학기술학회논문지
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• 제14권11호
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• pp.5601-5609
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• 2013

본 연구는 유아교육 현장에서의 유아용 교재 교구 활용에 대한 품질인식과 인증평가 제도적용에 대한 실태를 알아보는데 목적을 갖고, 2013년 4월 20일부터 30일까지 충남, 대전지역 어린이집에 종사하는 3년차 이상된 영유아반 지도교사 150명을 대상으로 설문조사를 하였다. 분석결과 첫째, 교재 교구 활용실태는 유아와의 상호작용에서 교재 교구의 질 중요성은 전체 96.1%가 중요하다고 생각하고, 대다수 교사가 교육, 보육과정을 고려한 교재 교구사용시 수량과 품질에 대한 높은 인식을 보였다. 또한 현장에서 유아교사와 교구간의 사용시 가장 불편한 점으로는 발달의 적합성(47.3%)이 가장 높고, 유아에 대한 사용의 편리성은 평균 3.54점으로 나타났다. 이 외에 놀이와 교구의 사용시 유아들의 교구활용에 대해 평균 3.89점으로 유익하다고 나타났으며, 현재 유아교육 현장에서 사용되는 유아 교구에 대해 평균 3.29점으로 보통 수준으로 나타났다. 둘째, 교재 교구에 대한 교사의 인식은 평균 3.99점으로 비교적 긍정적이었다. 이같은 결과는 유아의 어린이집에서의 교재 교구활용에 따른 교재 교구의 질이 매우 중요시 되고 있음을 입증시켜 주었다. 이는 교재 교구의 중요성과 유용성을 고려할 때 품질기준과 시설평가와 함께 교재 교구도 평가인증제도를 도입하여 품질이 보증된 제품의 공급으로 유아들의 안전과 사용에 따른 편익성을 보장할 수 있는 제도적 정책의 도입이 요구됨을 시사해 준 것이라 평가할 수 있다.

• 한국전자현미경학회:학술대회논문집
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• 한국현미경학회 2004년도 제35차 춘계학술대회
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• pp.94-96
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• 2004

• 해양환경안전학회지
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• 제26권3호
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• pp.286-296
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• 2020

Sandwich structures are general-purpose structures that can reduce the structural weight of composite ships. Core materials are essential for these structures, with polyvinyl chloride (PVC) foams being the most popular. These foam core materials are subjected to various tests in the development process, and must satisfy the performance requirements of several ISO and ASTM standards. Therefore, a procedure for evaluating the performance of foam core materials was proposed in this paper. In addition, prototypes were fabricated using a commercial PVC foam core product in accordance with the structural design of an 11 m fiber-reinforced plastic yacht. Then, a case study was conducted on the proposed evaluation procedure. The proposed procedure facilitates the understanding of the performance requirements and evaluation of core materials used in composite ships and is expected to be utilized in developing core materials for marine structures.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 1999년도 추계학술대회 논문집 - 한국공작기계학회
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• pp.301-306
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• 1999

Application of bonded dissimilar materials in various industries are increasing. When these materials are used in structures, it needs to investigate strength evaluation applying fracture mechanics. Al/Epoxy bonded dissimilar materials with an interface crack and an interface crack emanating from an edge semicircular hole were prepared for the static tests so that experiment of fracture toughness were carried out. Stress intensity factors of interface cracks in bonded dissimilar materials were computed with boundary element method(BEM) and the fracture criteria of mixed mode crack were analyzed. From the results, the fracture criteria and the method of strength evaluation by the fracture toughness in Al/ Epoxy bonded dissimilar materials were proposed.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2003년도 제24회 학술발표회 초록집
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• pp.89-89
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• 2003