• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.349_350
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• 2009

가스개폐기의 고장을 예방하기 위해서는 열화상태를 진단하여 고장을 일으키기 전에 교체하는 것이 가장 바람직하다. 이를 위해서는 제품의 제조상태, 불량가능성 등 이력사항을 진단하고 활선 진단을 통한 내부 상태를 파악한 후 위험도를 평가할 필요가 있다. 본 연구에서는 국내 배전개폐기의 열화 및 수명인자를 이용하여 개폐기 고장 위험을 예측할 수 있는 기법을 제시하였다.

• Computational Structural Engineering
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• v.3 no.3
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• pp.58-61
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• 1990

교량유지관리 업무는 교량의 건설(신설), 노후교량의 개축, 교통량 증가에 따른 교량의 확장, 보수를 통한 원상복구, 또한 보수기록의 보관문제, 기존교량의 계속적인 점검 및 조사 등으로 분류된다. 이러한 문제를 전산화 하는 것은 필요항목들을 특성별로 분류하여 각 항목 등에 대한 데이타베이스를 구축하고 교량의 점검 및 조사 등을 통하여 교량의 손상상태를 파악함은 물론 개축, 보수, 확장, 신설 등에 대한 판정 및 그 우선순위를 제시하여 주는 의사결정시스템 개발이다. 본 고에서는 교량관리업무를 전산화하기 위해 한국건설기술연구원에서 개발한 교량관리용 DB(DATA BASE)시스템에 대하여 간략히 소개하고자 한다.

• Journal of the Korean Institute of Educational Facilities
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• v.8 no.3
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• pp.7-14
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• 2001

To obtain basic data used for establishing the criteria of deterioration in renovation of educational facilities, current problems of material and method and quality improvements were examined. In this study, the elementary schools built 20 and 70 years ago were unintentionally chosen and studied. With the data of the repair of old educational facilities, the results are as follows. The First problem is that the construction priority which was based on non-experts decision. The Second problem is that maintenance method which changes the materials after their life was ended. So, refer to remodeling of educational facilities, the selections of proper materials and methods to use of each function were main object in this study.

• Korean Journal of Labor Studies
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• v.24 no.2
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• pp.247-291
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• 2018

This study investigates the employment structure and the social safety net experience of the subcontracting cleaning workers in Korea, who have been main targets of the labor outsourcing despite the necessity and permanence of their labour. This study specifically focuses on the fact that these subcontracting cleaning workers are mostly female and in their old age, and analyzes how the combination of their age, gender, and employment structure leads to the (mis)match with the Korean social security system. Case study with in-dept interview method has been conducted to the old-aged female subcontracting cleaning workers in Korea. The result of this study is as follows. It was the income insecurity that led them to (re)enter the labour market, and the cleaning work was the almost the only wage work they could do considering their age and gender. Cleaning workers are mostly employed in the subcontracting company, and thus their labour contracts depend on the business contract period between the original and subcontracting company. Consequently, their employment relationship is mostly insecure unless they are guaranteed employment succession through the collective agreement of trade union. Moreover, it has been discovered that the employment insecurity due to the indirect employment relationship led to the poor labour conditions, low wage, and the exclusion from the social safety net.

• Computational Structural Engineering
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• v.1 no.1
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• pp.113-122
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• 1988

A practical model for predicting the risk of fatigue failure of steel highway bridges is developed in this study. The proposed model is derived from fatigue reliability methods by incorporating various factors which may affect the fatigue life of bridges. The fatigue reliability function is assumed to follow the Weibull distribution. The computational form of the Weibull is adopted from Ang-Munse's approach that includes all the statistical uncertainties of the fatigue life of steel members and the stress ranges under variable amplitude loadings. The model accounts for the variation in ADTT, the change in stress history and the effects of inspections, which may occur during the serivce life of bridges. Stress range histograms are collected from the random stress spectra based on the field measurements of an existing bridge, and, thus, the resulting stress range frequency distribution is modelled with a beta distribution. The results of applications of the proposed fatigue analysis methods to an existing bridge show that the proposed models with the computer program developed for numerical computations can be used as a practical tool for the fatigue rating or for the predictions of the remaining fatigue life of deteriorated existing steel bridges.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 1998.05a
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• pp.4-4
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• 1998

서울 및 서울 인근 주민들의 식수 공급을 위하여 1978년에 건설된 매설 상수배관은 전기방식 조처없이 콜탈에나벨만으로 피복된채 지하철 및 각종 전기설비가 복잡하게 산재된 서울지역에서 근 20년 유지되고 있다. 따라서 이 배관에 대한 부식 상태를 파악하는 것이 배관의 안전성 확보 및 대책수립, 배관수명의 연장, 중단없는 상수공급 동의 차원에서 매우 중요하다. 이 조사의 목적은 건설후 20년이 경과하여 노후된 매설 상수배관에 대한 기본적인 부식환경 및 피복 상태를 조사하여, 부식상태를 진단하고 향후 대책을 세우기 위한 기초 자료를 확보하는 것이다. 조사의 대상은 1978년에 건설된 서울지역 매설 상수배관 103 Km이었으며, 주요 조사 내용은 토양의 pH, 토양비저항과 같은 기초적인 부식환경조사, 전 배관에 대한 부식전위측정, 부식환경 조사로부터 판정된 부식 우려구간을 대상으로 피복손상부 탐측 및 시험굴착, 그리고 상기 조사의 결과를 검토하는 것이다. 조사 결과, 기본적인 부식환경 변수로 예상되던 토양의 전기비저항, 습도, pH는 부 식전위 및 토양종류와 상관관계를 보이지 않았으며, 상수배관 주변의 토양비저항은 대부분 8,000 ~ 10,000 ${\Omega}{\cdot}cm$, 토양 pH는 대부분 5와 6사이에 집중되었다. 전체적으로 볼 때 매설 상수배관은 예상보다 양호한 배관 상태를 유지하고 있다고 판단되나, 일부 간섭구간은 방식보완이 필요한 것으로 조사되었다. 즉 일부 간섭에 의한 미방식 지역은 배류기나 희생양극 설치와 같은 조속한 방식보완 조치가 필요하며, 과방식이 우려되는 곳은 강제배류기의 출력을 크게 낮추는 것이 필요하다. 이때 부식전위가 크게 올라가는 지점이 있으면 부근 가까운 지하철 레일과 선택배류기로 연결하는 것이 바람직하다.

• Journal of the Korea Convergence Society
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• v.10 no.6
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• pp.259-268
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• 2019

The purpose of this study was to explore physical education majors' subjective perception on sports ideologies using Q-methodology. This study found four types of subjective perception on sports thoughts. Type I is named 'the type of fair victory and defeat.' The subjects of type I emphasize the items of victory and defeat, fair judgement, a drama without a scrip, etc. Type II is named 'the type of sport philosophy.' The subjects of type II emphasize the items of sport philosophy, theory of one of mind & body, great spirit, hwarangdo spirit, sport logic, self-improving, etc. Type III is named 'the type of communication & social activity.' The subjects of type III emphasize the place for communication, social activity, consideration, improvement of the quality of life, etc. Type III is named 'the type of communication & social activity.' The subjects of type IV emphasize welfare, security for the aged, leisure, entertainment(game), healthy, etc.

• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.6
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• pp.197-205
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• 2020

In 2014, The Housing Act amended to allows vertical extension and increases the units of housing (or total floor area) to site. Currently, the feasibility of performing vertical extension is evaluated based on safety diagnosis provisions and manuals with 1st investigation stage on slope, uneven settlement, load-bearing capacity, and durability. However, a need for more reasonable evaluation criteria for the investigation is still required because there had not been any other case study on the diagnosis for the vertical extension, and the engineering basis on evaluation criteria were not suggested. Accordingly, this study is intended to suggest feasible evaluation criteria on the carbonation, chloride ion contents, corrosion of reinforcements, crack and surface deterioration of concrete for durability assessment by codes and standards of domestic and foreign countries. The results of this study are expected to be beneficial for establishing more reasonable durability evaluation criteria, and in turn, more reliable assessment protocol for vertical extension.

• The Journal of Engineering Geology
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• v.28 no.2
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• pp.297-312
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• 2018

In order to assess the safety diagnosis and grouting reinforcement effect of old reservoir facility, local governments and public offices mainly use electrical resistivity survey. However, electrical resistivity survey is a qualitative evaluation that varies the resistivity value by various exploration conditions. It is also difficult to grasp the stiffness change directly related to the stability of reservoir, thus an electrical resistivity survey is not applicable to continuous stability monitoring after grouting. The purpose of this study is to investigate and validate the quantitative evaluation of reinforcement effect of reservoir with cement grouting through shear velocity (Vs), which is closely related to the stiffness (${\mu}$) of the ground. This study was carried out on two reservoir facilities. The reinforcement effect was evaluated by comparing the permeability test, standard penetration test, down-hole test and MASW(Multi-channel Analysis of Surface wave) survey before and after cement grouting. Shear wave velocity changes before and after grouting were analyzed by phase velocity difference and inversion analysis, respectively, and the reliability of the analytical results was evaluated by comparing with field test results. Shear wave velocity increases to 5~10% in case of the D levee, and 10~20% in the levee of H reservoir. These results are showed similar pattern to the field test results.