• Journal of Korean Association for Spatial Structures
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• v.11 no.1
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• pp.97-104
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• 2011

This paper contains of descriptions of deterioration diagnosis of the surface and a coating layer for maintenance managements of large spatial structures with membrane structure. Membrane is a roofing material of the structures that its performance of durability including its performance of chemical resistance and corrosive resistance is considered to be highly important. In general, the items of diagnosis for maintenance managements such as membrane extensively include the diagnosis of deterioration of the membrane surface, of a coating layer of membrane, the diagnosis of deterioration between a coating layer and fiber, of overall surface of membrane, of the class of ropes, of reinforced belts, and of the cover of rubber. The object of this study that needs maintenance managements of the membrane with PVC and FIFE which are commonly used and shows the diagnosis results of deterioration of the surface and a coating layer.

• Composites Research
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• v.27 no.2
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• pp.59-65
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• 2014

Most of energy are obtained from oil, coal, and natural gas, most likely, fossil fuel which is limited throughout the world. Recently, high crude oil price, climate change, oil depletion, etc. are main reason to get attention to non-fossil energy including renewable energy in the world. In this study, we studied analysis and design of structure system composed of pultruded fiber reinforced polymer composite (PFRP) which has many advantages such as high specific strength and stiffness, high corrosion resistance and chemical resistance. For the design and construction of floating-type structure, PFRP structural members may be the first choice. Design of tracking-type floating PV generation structure was performed by using the results of the finite element analysis. The structure is fabricated and installed on the water surface. Before the installation of the structure, safety related problems associated with installation and operation are investigated using the finite element simulation and it was found that the structure is safe enough to resist externally applied loads.

• Journal of Korean Association for Spatial Structures
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• v.10 no.2
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• pp.127-134
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• 2010

Membrane structures are now used in various ways throughout the world with the merits of free shape, lightness, durability, sunlight transmittance and homogeneous material. The development of new membrane material opened up new possibility for the design of new building structures. Recently it was mainly used PVC, PVF, PVDF, PTFE, ETFE membrane for using the roofing material of membrane structures. Some problems of architectural membrane have fire proofing, lack of strength, tear resistance, durability and elasticity. For the estimation of this problems, it will be tested the basic mechanical properties of membrane material about tensile strength, tearing resistance and repeated loading behavior. Elastic modulus is 337.30~1257.63N/$mm^2$, and strain is 17.90~26.91%.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2008.11a
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• pp.229-234
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• 2008

Performance based fire engineering design is being adopted around the world as a rationed means of providing efficient and effective fire safety in Building. This development is being supported by the adoption of performance based codes which specify the objective and minimum performance requirements for fire safety traditional design for fire safety which is still practiced in many countries, relies on "prescriptive" codes which specify how a building is to be built, which no statement of objective and little or no opportunity to offer more rational alterative design. It is the aim of this study to investigate and analyze the research direction of structural fire resistance design of steel structures for recommendation of PBD in Korea.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2008.11a
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• pp.195-201
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• 2008

When reinforced concrete is subjected to high temperature as in fire, there is deterioration in its properties of particular importance are loss in compressive strength, cracking and spalling of concrete, destruction of the bond between the cement paste and the aggregates and the gradual deterioration of the hardend cement paste. Assessment of fire-damaged concrete usually starts with visual observation of color change, cracking and spalling of the surface. In this paper, it was reported the trends of research and practical use on the Explosive Spalling Properties of the High-Strength Concrete.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.110-110
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• 2012

탄소나노튜브와 그래핀 소재는 나노 스케일의 탄소를 대표하는 소재로서 전기적, 기계적인 특성이 뛰어나며, 화학적으로 안정하고, 환경 친화성을 가지고 있다. 탄소나노튜브의 경우 전기적으로 도체 및 반도체성을 가지고 있을 뿐만이 아니라 직경이 최소 1 nm 수준으로 종횡비 및 비표면적이 매우 큰 특성을 가지고 있어서 차세대 정보 전자소재, 고효율 에너지 소재, 고기능성 복합소재, 친환경 소재 등의 분야에서 많은 응용연구가 활발히 진행되고 있다. 그래핀의 경우 실리콘의 100배에 이르는 전하 이동도, 구리의 100배에 이르는 전류밀도를 가지며, 열전도도 및 내화학성이 뛰어나고 다양한 화학적 기능화가 가능할 뿐 아니라 뛰어난 유연성과 신축성을 보이면서 그래핀 자체의 물리화적 특성구명과 더불어 투명전극, 반도체, 에너지 전극, 구조체, 가스 베리어 등의 응용연구가 최근 활발히 진행되고 있다. 본 발표에서는 최근의 나노카본 기반의 투명전극 및 기체 차단 필름의 연구 개발동향 등에 대해 발표하고자 한다.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1996.10b
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• pp.123-128
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• 1996

Bench Scale급 건식 가스화기에서 중국 Datong탄과 미국 Alaska Usibelli탄으로부터 생성된 Slag의 구조적인 특성과 화학적인 특성을 조사하였다. Datong slag은 표면이 매끄럽고 검으며 속이 약간 비어 있는 구형을 띄고 있고 Alaska Usibelli탄으로부터의 slag은 속이 조밀하게 차여있는데, 이들 slag의 내부는 Datong, Alaska Usibelli탄 두 경우 다 회분이 결정화된 형상의 특징을 보여주고 있다. 그리고 Cu, Zn외 11가지 중금속이 slag에 다량으로 농축되어 제거되었음을 알 수 있었으며, slag들의 침출여부를 조사하기 위하여 용출시험을 수행한 후 용출액에 대하여 중금속 분석을 한 결과 대부분 중금속들은 검출되지 않았다. 내화재의 주성분인 Cr이 slag에 포함되어 나오는 것으로 측정되었으나 용출시험 결과 검출이 안되어 2차오염에는 전혀 문제가 없음이 입증되었다. 따라서 건식 가스화기로부터 생성된 slag을 재사용할 때, 용출되는 중금속에 관한 2차 환경오염이 유발되지 않을 것으로 확인되었다.

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.03a
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• pp.194-194
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• 2003

지르콘은 내침식성, 내마모성, 열 충격 저항성 및 기계적 물성이 우수하여 내화재료, 연마재료 등으로 다양하게 활용된다. 이러한 지르콘의 물성은 출발원료의 입도와 순도, 첨가제, 열처리 온도 등에 크게 의존한다. 본 연구에서는 출발 물질의 평균 입도를 각각 5$\mu\textrm{m}$와 3$\mu\textrm{m}$, l$\mu\textrm{m}$ 이하로 제어하였고, 시료의 열처리 온도를 135$0^{\circ}C$, 140$0^{\circ}C$, 145$0^{\circ}C$, 150$0^{\circ}C$, 155$0^{\circ}C$로 소결하였다. 각각의 지르콘 소결체는 미세 경도 측정, 결정상 분석, 밀도 측정, 미세구조 관찰을 통하여 특성 평가하였다. 미세경도 값은 140$0^{\circ}C$에서 소결된 지르콘의 가장 높았으며, 밀도는 150$0^{\circ}C$에서 소결된 지르콘이 가장 높으며, 155$0^{\circ}C$에서 소결된 지르콘은 과소결되어 전체적으로 물성이 저하되는 것을 관찰하였다.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.05a
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• pp.214-215
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• 2014

Technologies on energy saving and materials used in curtain walls have progressed with increase of high-rise and large buildings. This study is explain fire resistance performance of the curtain walls. And focused on bond strength of light-weight inorganic ceramic board in high temperature for fire resistant curtain-wall system. From the result, curtain-wall system high fire resistant using the light-weight inorganic ceramic board.

• Journal of the Korea Furniture Society
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• v.24 no.4
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• pp.426-432
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• 2013

Fire resistance and impact sound insulation tests were performed for a floor assembly, of which stiffness was reinforced by shortening the span of floor joists by installing glulam beam additionally in the middle or one thirds of the original span, and which an additional ceiling component was installed apart from floor structure. By applying the isolated ceiling, timber framed floor showed 1 hour of fire resistance even in case that dead load was increased by considering cement mortar layer for radiant floor heating. Insulation performance against light and heavy impact sound was improved significantly by applying the sound absorbing layer of big mass and high elasticity in addition to the stiffness improvement and isolated ceiling.