• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2013년도 추계 학술논문 발표대회
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• pp.173-174
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• 2013

In this study, the tensile properties of sealants by heat deterioration were measured and analysed to gather the basic data of sealant because these studies do not have been investigated in Korea. Most general one-component silicone sealants were used and test specimen was I-type. The test parameters are sealant types which have different density and heat deterioration time in 80℃. As a result, the rat of reduction in area by heat deterioration was considerable increased at SR-A compared with SR-B. The tensile properties by heat deterioration decreased at SR-A because the specimen by deterioration occurred adhesive failure before tensile test. However, SR-B specimen was increased at maximum tensile stress but decreased at elongation in maximum tensile stress. Also, Maximum principal stress was measured at the edge of specimen by FEM simulation in order to find out failure points.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2002년도 가을 학술발표회 논문집
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• pp.667-672
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• 2002

Concrete cooled to very low temperature cyclically is deteriorated by ice formation in micro-pores. Although the factors to the deterioration are various, storage at very low temperature is mentioned as one of the factors. In practice, storage of cryogenic structure is kept at very low temperatures, and as such, it is important to take into consideration the influence of storage at such low temperature on the deterioration of concrete. Thus, in this study, the influence of storage on the deterioration of concrete at minimum temperatures taking into consideration the different W/C and air content.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2016년도 추계 학술논문 발표대회
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• pp.85-86
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• 2016

Recently damages caused by the additional costs and degradation in durability combined deterioration due to plain concrete deterioration has occurred. In particular, in the case of the finish that is not exposed to the outside air in the concrete to respond to the harsh environment (freeze-thawing, calcium laying, etc.), to establish a quality control way for the process and the concrete mix design for it.

• 전기의세계
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• 제24권5호
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• pp.82-90
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• 1975

This study investigated the deterioration phenomena of the Polyethylene surface contaminated with organic(Saccharose) or inorganic(NaCl) matters through electrical and optical experiments. And also these experimental results relatively well coincided with which was treated by theoretical process. On the electrical experiment, relation between electric field intensity in corona discharge and time reached to the breakdown, and relation between total amount of charges discharged and increment of applied voltage were investigated. On the optical experiment, discharge time dependence of surface deterioration rate and process of surface deterioration in the X-ray diffraction pattern were investigated. It was concluded that chemical effects by the corona discharge deteriorated insulation characteristics of Polyethylene surface.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 봄 학술논문 발표대회
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• pp.101-102
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• 2023

This study aims to mix the base concrete by mixing latex to improve the durability performance to reduce the composite deterioration of the base concrete. Latex fiber has high resistance to freezing and thawing, adhesion, and deicing agent (calcium chloride), and it is used to secure long-term durability to reduce cracking and compound deterioration of concrete. In addition, through experiments, we are trying to find ways to improve the strength of concrete by studying the mixing of the appropriate mixing ratio of latex.

• Corrosion Science and Technology
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• 제8권2호
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• pp.53-61
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• 2009

본 연구에서는 강교 도장재료로 사용될 수 있는 에폭시 하도 도료를 도포한 시험편을 촉진시험을 통해 열화시킨 후 도막의 외관 평가 및 EIS에 의한 평가를 실시하고, 그 2가지 방법에 대한 비교 분석을 실시하였다. 화상처리 기법에 의해 구한 총 열화 면적율과 열화도 평점 산정 결과를 상호 비교해 본 결과 녹이 발생한 경우가 그렇지 않은 경우보다 열화도 평점이 높게 나타났다. 이는 강교 도장의 열화도 평가 기준에서 단위 열화 면적율당 부여하는 열화도 평점이 박리의 경우보다 녹의 경우가 더 크기 때문이다. 열화 면적율과 EIS 측정 데이터를 비교해 본 결과 녹의 면적율 약 0.1% 이상, 블리스터링의 면적율 약 3% 이상만 되어도 도막의 임피던스는 약 $10^4{\Omega}{\cdot}cm^2$ 혹은 그 이하로 크게 저하되었다. 2개의 시험편을 제외한 모든 시험편에 대해 전하전달저항(charge transfer resistance, $R_{ct}$)과 이중층 정전용량(double layer capacitance, $C_{dl}$) 값이 나타났으며, 이 결과로부터 이들 시험편들은 도막과 강재 계면에 수분이 축적되어 부식이 진행되고 있음을 알 수 있었다. 열화도 평점과 EIS 측정결과를 상호 비교해 본 결과 저주파수(10 mHz)에서의 임피던스 값이 $10^6{\Omega}{\cdot}cm^2$ 이하로 떨어진 경우는 모두 열화도 평점이 10점 이상으로 나타났으며, NORSOK cyclic test 과정에 의해 열화시킨 경우 열화도 평점이 높지 않음에도 불구하고 임피던스는 가장 낮게 나타났다. 이것은 도장계와 열화조건이 주 시험편과 다르기 때문인 것으로 판단되며, 열화조건이 더 가혹하거나 복합적일 경우 외관 상태에 비해 도막의 저항이 더 크게 저하될 가능성이 있다고 생각된다.

• 한국방재학회 논문집
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• 제8권5호
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• pp.15-21
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• 2008

본 연구의 목적은 현재 지방자치단체에서 수행하는 상수관로 개량 및 교체 사업시 상수관로의 노후도 평가를 위한 항목별 가중치를 산정하는 것이다. 상수도시스템에 상수관로의 노후도 항목은 지역 및 위치, 토지이용 등의 특성에 영향을 받을 수 있다. 본 연구에서는 국내외 자료를 바탕으로 국내 실정에 맞는 노후도 항목 16개를 선정하였다. 또한, 노후도 항목별 세분화된 가중치 산정을 위해 실무업체를 선정하여 해당 전문가들을 대상으로 노후도 항목별 중요도에 대한 설문을 실시하였다. 설문 조사 방법으로는 델피법을 이용하여 이 결과를 바탕으로 계층적분석과정(AHP)을 적용하여 노후항목별 가중치를 산정하였다. 분석결과 국내 실무에 적합한 16개 결함항목별 점수배점표를 작성하여 명확한 판단기준을 마련하였으며 관거 개량사업에 있어서 복잡한 의사결정 문제들에 대한 활용 가능성을 제시하였다.

• 한국식생활문화학회지
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• 제18권5호
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• pp.475-482
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• 2003

오미자 추출물의 가열 및 저장에 의한 변색을 지연시킴으로써 식품 소재로써 오미자 추출물의 이용도를 증진시키고자 식품에 가장 광범위하게 이용되는 첨가물인 당과 색소 안정화제의 효과를 조사하였다. 단당류로써 glucose, fructose, 이당류로써 sucrose, maltose를 처리한 결과 단당류는 가열에 의한 변색을 촉진시켰고 이당류는 가열에 의한 변색을 억제시키는 효과가 있어 maltose를 10%처리하였을 때 40%정도 변색이 억제되었다. 색소 안정화제 로 각각 1%와 5%의 maltodextrin, ${\beta},\;{\gamma}-cyclodextrin$, ascorbic acid, phosphoric acid를 첨가하여 조사한 결과 ${\beta}-$ 및 ${\gamma}-cyclodextrin$과 maltodextrin 5% 처리구의 경우 DI값이 대조군보다 낮게 나타나 가열 변색에 대한 안정화 효과를 나타내었다. 복잡한 구성성분으로 인하여 matrix 효과를 나타내는 식품에의 적용효과를 조사하고자 오미자 색소 추출물을 첨가한 겔 시스템을 모델 식품으로 사용하여 $25^{\circ}C$ 및 $35^{\circ}C$에서 저장하면서 표면 색도의 변화를 측정하였다. 저장 온도 및 기간이 증가할수록 a값이 감소하는 경향을 나타내었으며 maltodextrin을 5.0% 첨가한 경우 a 값이 $15{\sim}20%$증가하여 matrix effect가 고려된 실제 식품에서도 색소안정화 효과가 확인되었다.

• 한국주거학회논문집
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• 제20권4호
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• pp.131-142
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• 2009

High-rise and high-density apartment complexes have been built and supplied on a large scale in the 1st period of the New Town project in metropolitan areas since the late 1980s. Now It has become necessary to improve those apartment complexes, which have serious deterioration problems for aging more than about 20 years accompanying simultaneity and a large scale. The purpose of this research is to develop the evaluating indicators to measure the level of deterioration of apartments inclusively and practically in order to regenerate apartments as sustainable residential environments. This study is composed of the following four parts; (a) establishing the conceptual model of evaluation of apartment deterioration, (b) selecting evaluation items, (c) constituting evaluation measurement, and（ｄ)weighting evaluation indicators. First, deterioration of apartments was conceptualized by physical. social, and economical aspects in terms of sustainable development and proposed the conceptual model of hierarchy structure of evaluation of apartment deterioration by literature reviews. Second, evaluating items were selected based on literature reviews of existing indicators and preceding studies about apartments of Korea and foreign countries. The evaluating indicators were identified as a total of 77 evaluating items which were composed of three dimensions and 9 attributes on the basis of the conceptual model. They cover comprehensive scope of the apartment such as unit, building, complex, and site. Third, as the measurement, the 5 point ordinal scale measure was suggested. The evaluating measurement including measure standards, measure methods, and measure contents were developed by each evaluating items. Lastly, the weighting of evaluating indicators was analyzed by AHP method conducted by survey on the expert group. Items were identified as high contributors or low contributors. The weighting of these items could suggest several evaluations according to the situation. The evaluation of the level of deterioration can be done by both total evaluation and a specific field of evaluation. In addition, it is easy to grasp deteriorated attributes or dimensions by providing a radar and bar chart showing evaluation results. These evaluating indicators could be a useful tool to grasp actual methods for the regeneration of apartments.

• 교육시설 논문지
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• 제24권6호
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• pp.11-18
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• 2017

Education facilities have much affect to make a good condition for the learning environment. Therefore, various approaches have been conducted to improve the physical, social and educational achievement. Especially, the physical aspect is very important to get rid of the building defect and improve the student their learning environment. For these, it needs to explain the performance and function of components and materials, which is linked with the deterioration degree. The deterioration degree is a imperative factor to make a decision whether the component would be repaired or not and to provide the repair scope of its component. In this paper, it aimed at making the deterioration degree model of roof proof under the hypothesis of which deterioration degree would be equal the repair cost at this time. Results of the study are shown that first, the $3^{rd}$ function is most proper to explain the deterioration degree model among 11 functions in view of resulted statistics. Second, the inflection of deterioration is shown at 15yr of the elementary school and 13yr of the middle and high school. This study has a limit of disclassification of the component or materials and it is, therefore, favorable to include the classification of waterproof material and work. These results would make a change from the breakdown maintenance to preventive maintenance and give a decent the learning environment for student.