• 월간 기계설비
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• no.12 s.209
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• pp.34-43
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• 2007

환경부는 산하 수처리선진화사업단에서 수돗물 수질개선대책의 일환으로 연구개발한 옥내급수관 진단, 세척 및 갱생기술을 적용, 서울시와 공동으로 시범사업을 실시한다고 밝혔다. 이 사업은 서울 둔촌동 주공아파트 2개동 80세대를 대상으로 약 1억2000만원의 예산을 들여 지난 8월 말부터 시행, 수돗물 녹물발생 방지를 위한 갱생기술의 완성도를 검증·확인한다는 것. 기존 옥내급수관 갱생기술은 평균 관직경 15mm인 소형관에 대한 정밀시공이 어려워 녹이 재발하는 경우가 많았다. 하지만 이번에 개발된 기술은 수도관 내부의 녹 제거 및 관 내부 표면이 균일토록 코팅할 뿐 아니라 시공 후 마이크로 로봇을 이용, 관 내부 촬영 및 절연도 체크를 통해 코팅 완성도를 확인, 녹 재발 가능성을 미연에 방지한다. 이번 기술이 검증되면 환경부는 선박배관, 빌딩, 냉각수배관, 소화용배관, 산업용배관 등에도 확대 적용하고 해외진출을 통해 물산업 육성 아이템으로 발전시킬 계획이다. 한편 환경부는 지난 2005년 수도법을 개정, 건축연면적 6만$m^2$이상 다중이용건축물과 연면적5,000$m^2$이상 국.공립 공공시설은 준공 5년 후부터 매년 수질검사를 실시, 결과에 따라 수도관을 세척·갱생 또는 교체토록 올해 1월부터 의무화 하고 있다.

• Fire Science and Engineering
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• v.25 no.2
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• pp.88-94
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• 2011

Heat release characteristics of live fire load are an important parameter for performance oriented fire safety design of a building. While investigations have been carried out on the fire load and its burning behavior in office, residential and commercial buildings and so on, little effort has been paid for the rational treatment of fire load in bookstore. In this report, burning behavior of typical combustible objects in bookstore are studied by measuring heat release rates of bookshelf with book. Based on the results, it has reviewed fire safety when a fire accident occurs on the large bookstore and suggested peak heat release rate per burning surface, fire growth rate, etc of the live fire load required for fire safety design in bookstore.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.306-306
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• 2015

기존 토사유출실험 연구는 대체로 유출구에서 유사의 총량을 일정한 시간 간격으로 측정했다. 이 같은 방식으로는 총 토사유출량의 시간적 변화는 알 수 있으나, 토사유출의 공간적 분포 변화는 알 수 없기 때문에 토사유출의 취약지점을 파악하고 이를 제시할 수 없다. 본 연구에서는 이러한 한계를 극복하고자 입체사진측량 기법을 도입하여 토사유출의 공간분포를 측정하고 각 지점이 총 토사유출량에 기여하는 정도를 파악하였다. 토조($2m{\times}1m{\times}0.3m$)로부터 약 1.5 m 높이에서 고해상도 디지털 카메라를 이용하여 토조 내 표면을 촬영하였고, 입체사진측량 기법을 이용해 토조 내 수치표고모형(Digital Elevation Models)을 추출하였다. 수치표고모형 추출 과정에서는 고도값의 오차 범위를 확인하였고 격자 해상도를 다양하게 설정하면서 최적의 격자 해상도를 평가해보았다. 최종적으로 구한 일련의 수치표고모형으로부터 토사유출의 시공간적 변화를 파악할 수 있었으며, 이는 토조 내 토사유출 과정에 대한 보다 세밀한 이해를 가져올 것으로 기대된다.

• Journal of the Korea Institute of Building Construction
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• v.21 no.6
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• pp.539-550
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• 2021

In this study, Zn and Zn-15Al were coated on general carbon steel by plasma arc metal spraying and then immersed in a 3.5wt.% NaCl solution similar to the seawater environment to evaluate the corrosion resistance properties. Through the surface shape analysis test by SEM and XRD, it was found that the Zn coating was porous and needle-shaped, so the penetration of the electrolyte was easy, and thus the corrosion rate was rapid. On the other hand, the Zn-15Al coating had a uniform and dense shape and was shown to suppress corrosion.

• Journal of the Korea Institute of Building Construction
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• v.23 no.4
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• pp.393-404
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• 2023

This research evaluates the antibacterial and transparency properties of UV-curable paint augmented with 20wt% copper particles. The transparency assessment indicated that the paint maintained a total luminous transmittance of 90% or above, thereby matching or surpassing the performance of standard UV-curing paints. To further test its antibacterial capabilities, wooden flooring boards were coated with the UV-curable paint laced with 20wt% copper particles, which had been surface-modified with a silane coupling agent. Following the fatigue tests of these treated boards, an impressive bacterial reduction rate of 99.9% was noted after a span of 6 hours, demonstrating the paint's exceptional antibacterial performance.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.11a
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• pp.107-108
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• 2022

In recent years, the construction industry has a tendency to increase of high-rise builidngs. High rise buildings can use limited space efficiently. But High rise buildings have problem that have extremely heavy weight. Various studies are being conducted to reduce the weight of buildings. Although lightweight aggregate is a meterial that can effectively reduce the weight of buildings, the strength of the aggregate itself is weak and the absorption rate is high, so the strength of the ITZ(Interfacial Transition Zone) area is weak. Therefore, it is essential to improve the interfacial area when using lightweight aggregates. In this study, an experiment was conducted to improve the adhesion between the aggregate and cement paste and to strengthen the interfacial area by coating the surface of the lighteight aggregate with Blast Furnace Slag. To confirm the improvement, compressive strength and EIS(Electrochemical Impedance Spectroscopy) measurements were perfromed. Using EIS, the change in electrical resistance of the cement hardened body was confirmed. As a result, it was confirmed that the lightweight aggregate coated on the surface showed highter compressive strength and electrical resistance than the non-coated lightweight aggregate, and that the coating material was filled in the interfacial area and inside the aggregate that helped to strengthen the compresssive strength and higher electrical resistance.

• Korean Journal of Heritage: History & Science
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• v.47 no.4
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• pp.58-73
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• 2014

In general, it is thought discoloration on wood is frequently found in decorative wood products. So this study was conducted focusing on white rot found lower parts of columns and baseboards of a wooden house, Hyunchungsa (shrine) to know whether microorganisms have any influence on discoloration or there is correlation with strength by investigating resistograph, occurrence of microorganisms and microscopy for analysis(SEM, tissue analysis etc.). The results obtained were as follows: (1) The result of measurement of resistograph showed there are little correlation between discoloration and strength though there was a spot indicating low resistance. (2) The moisture content of discolored part was relatively higher than that of normal parts, but occurrence of microorganisms was less in discolored parts while more kinds of microorganisms were identified in normal parts with high CFU(Colony Forming Unit). (3) The result of SEM (with a magnification of 500 times) on the surface of discolored parts, it was found out there are many kinds of particles in different sizes on the surface and those were composed of elements such as C, O, Si, Ca, and a small amount of Na and Cl (weight %) were detected in part. (4) The result of tissue analysis showed discoloration occurs limitedly to the outer surface of column. As these results, it is concluded that discoloration has nothing to do with strength, damage by microorganisms and salt.

• Journal of architectural history
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• v.15 no.4
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• pp.37-56
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• 2006

Introducing International Style, P. Johnson and H. R. Hitchcock gave three standards to be the Modern, volume and surface, regularity, and exclusion of applied decoration. In spite of the negation of stylistic, formal approach in the Modernist Manifestoes, one usually have understood Modernity in Architecture with its formal character, especially with no ornament and flat, abstract, white surface. Modernism as a new paradigm in architecture have emphasized that there is no representation of anything outside and only present architecture in itself. They said that Modernism only cared about the language of Architecture without figural reference. So apparently there is no way to prove to its Modernity with formal condition. Modernity is in Spirit and contents. But actually we understand well its existence by visual communication This study deals with this difficult situation how Modernity represents itself without visual media and asks the question how simultaneously it presents its thingness and materiality In order to analyse contradictory situation between representation and presentation in Modern Architecture we need to survey the historical process of changing position of ornaments and its meaning in time. With the crisis of representation the role of ornament have seriously changed and divided. It caused the two situation in pre-Modern Architecture. Firstly, Architecture tend to be a high art and formal expression became important much more. The Use of Ornament became a kind of fashion to show the power, class, money. Secondly, Ornament lost its cultural weight and the structure and material aspect became the central in architecture. Rational Structuralism would be the essential character in Modern Architecture. Here the theory of G. Semper and A. Loos on cladding(dressing) and Ornament can help its problems and limits. In the situation without conventional ornament Modernists need to present modernity with new media that only show the thing itself and by that it does not represent any thing else as like the value, idea outside buildings. They believed that only it concerned esthetics and morality in architecture. But in reality it referred to art and machines as like ships, aircraft, and cars. By excluding Ornament and showing the process of clearing, abstract, flat, white surface 'represent' Modernity by the indirect way referring the concept of transparency, reason, sanitation, tectonics, etc. An Ideology and myth intervened architectural discourse to make the doxa about the representation in Architecture. Surface must be a different kind of media and message that can communicate in different way with compared to conventional Ornament. Decorated Shed by R. Venturi and Post-Functionalism by P. Eisenman, that are the most famous post-modern discourse, shows well difficult and contradictory condition in contemporary architecture concerning representation and form, meaning and form.

• Journal of the Korean Recycled Construction Resources Institute
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• v.7 no.3
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• pp.224-234
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• 2019

Waterproof layers are installed in civil engineering structures and bridge construction is commonly finished by applying a layer of regular or asphalt concrete above the waterproof layer. However, asphalt materials are susceptible to melting at high temperature due to its superior temperature sensitivity, and this causes the waterproofing material to melt due to the high temperature of the asphalt concrete, thereby increasing the defect occurrence rate due to the thickness reduction. In this study, tensile strength and elongation of hard and soft type of MMA(Methyl Methacrylate) applied to bridges were compared in accordance to standard performance criteria based on different mixture ratios. Results of comparative testing showed that hard MMA resin can display a satisfactory tensile strength, and soft MMA resin displays satisfactory elongation properties, but as the two resin types are separately used, neither types are able to satisfy the standard requirements outlined in KS F 4932. When the amount of the powder exceeds 56.25% of the total amount, voids are generated on the surface after curing and self leveling was impossible and a heterogeneous surface is formed. Furthermore, when the hard resin: soft resin: powder mixture ratio was set to 15g: 85g: 150g. the tensile strength was $1.5N/mm^2$ and the elongation percentage was 133% which satisfy the tensile performance of KS F 4932.

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.2
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• pp.185-190
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• 2021

Cement has been used as a main material in the modern construction industry. However, it has been pointed out as a main cause of global warming due to carbon dioxide generated during manufactured. Recently, research that replacing cement substitute to industrial by-products such as Blast Furnace Slag which is by-producted in steelworks. When Blast Furnace Slag is used as a cement substitute, it shows a problem of lower initial strength, which is caused by glassy membrane on the particle surface. In this study, we used Electrolysis Alkaline Aqueous to improve the usability and problem of lower initial strength. As a result of the experiment, cement matrix using Blast Furnace Slag and Alkaline Aqueous showed initial strength and hydrate product were developed than that using general mixing water. Also, as a result of porosity analysis, It was confirmed that cement matrix using Alkaline Aqueous and Blast Furnace Slag has a tighter structure in internal porosity and porosity distribution than using general mixing water.