• 한국철도학회:학술대회논문집
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• 한국철도학회 2002년도 추계학술대회 논문집(I)
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• pp.465-470
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• 2002

Construction of Yamanashi Maglev Test Line in Japan was proceeded based on "superconducting maglev Yamanshi Testline plan" approved by Ministry of Transport Government of Japan in 1990, which was performed by Yamanashi Maglev Test Line construction project team organized by personnel of Japan Railway Construction Public Corporation, RTRI and Central Japan Railway Company, and overall adjustment test was performed. Yamanashi Maglev experimental project team was organized, sponsored by RTRI and Central Japan Railway Company from April in 1997. Running test for the application was performed by this project team. Technical availability was proved by "superconducting maglev committee" of Ministry of Transport Government in March, 2000. In this paper, train radio system by LCX and by millimeter wave will be reviewed.

• 국제학술발표논문집
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• The 6th International Conference on Construction Engineering and Project Management
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• pp.450-453
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• 2015

The Construction Engineering Industry (CEI) is construction field based on professional knowledge, staff and information service, and is distinguished by construction activity. The contemporary CEI market has extended globally and diversified construction work classifications. International construction engineering companies now have an important economic and social effect. Over the last five years (2009 to 2013), the top-200 global engineering firms reported global revenue that grew from 54.4 billion to 71.5 billion, about 27% growth (ENR, 2014). Countries such as the U.S.A., Canada, those in Europe (Several developed countries, i.e., United Kingdom, Netherlands, France, Spain, France, Italy, and Spain), Australia, Japan, China, and Korea comprise the bulk of world construction engineering revenue. Although the construction engineering market continues to grow, much of the work is limited to Europe, mid-Asia, and Asia. Additionally, specific construction types are focused on building projects, industrial plants, and refining plants. As such, there are imbalances in the construction engineering market and some market saturation. Further, there is heavy competition and the construction engineering market may shrink in the future. This paper analyzed various factors affecting the construction engineering market, specifically looking at construction classifications and factors related to a global market. To accomplish this, we collected to data from Engineering News Record (ENR) and recast each variable. And we used nonparametric statistics because the number of cases were small, making it difficult to assume a case's population parameter. Then we tested with the Kruskal-Wallis test and drew results. The results indicate that concentration in particular construction types and extending global regional markets will be have a positive effect on the overall global construction engineering market..

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1997년도 가을 학술발표회 논문집
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• pp.409-416
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• 1997

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2005년도 춘계 학술기술논문발표대회 논문집
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• pp.13-16
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• 2005

Generally, as corrosive protection processing of a steel structure, zinc galvanizing and heavy duty coating paint are applied. However, zinc galvanizing has the difficulty of restriction of a size, or on-site construction. Moreover, heavy duty coating paint has a problem with many administrative and maintenance expenses with short problem of adhesion, corrosion generating of a damage portion, and maintenance management cycle. In this study, a salt water spray test, CASS test, and the electrochemistry examination were carried out for the thermal metal spray method of construction for corrosive protection performance evaluation. Moreover, the corrosive protection life of a thermal metal spray method of construction was quantitatively calculated on the basis of this experiment. in consideration of LCC, the economical efficiency of a general corrosive protection method of construction and a thermal metal corrosive protection method of construction was compared. Consequently, although initial construction expense was estimated 16 to $30\%$ high, as for a thermal metal spray method of construction, it turns out that the administrative and maintenance expenses for 100 years became cheap 9.3 to 13 or more times.

• 교육시설 논문지
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• 제24권6호
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• pp.3-10
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• 2017

The efforts for sustainable development in building construction is widely applied by global organizations, governments, etc. However, according to the researchers, if the green rating systems on the building, it is reported that construction costs and durations are increased compared to conventional buildings. In this respect, the objective of this study is to identify the construction costs between LEED and non-LEED buildings. The scope of this study is limited in 21 university buildings of Canada. The methodology is as follows: First, the data of LEED and non-LEED buildings are collected in every university building. Second, the average construction costs per square meter is collected and normality check is conducted. Third, to identify statistical significance, the difference of average construction costs is analyzed by using T-test. As a result, it is concluded that the construction costs of LEED buildings are increased by approximately 3.8% more than non-LEED buildings. In the future, the results of this study can be applied to analyzing the additional costs according to the LEED grade in educational buildings.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.142-143
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• 2007

A 1MW class HTS(High-Temperature Superconducting) synchronous motor has been developed. This motor is aimed to be utilized for industrial application such as large motors operating in large plants. The HTS field coil of the developed motor is cooled by way of Neon thermosiphon mechanism and the stator coil is cooled by water through hollow copper conductor. This paper describes performance test results of our motor, which was conducted at steady state in generator mode and motor mode.

• 국제학술발표논문집
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• The 4th International Conference on Construction Engineering and Project Management Organized by the University of New South Wales
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• pp.614-620
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• 2011

Delays in completing construction projects have significant financial and social impact to all parties involved in the construction process and in particular in developing countries. This is very evident in most construction projects in Libya and in both public and private sectors. The research study was initiated by Libyan Government and the main aim of the project is to develop a new strategy in reducing the impact of delay factors. In order to achieve this, a number of objectives have been set-to conduct a comprehensive literature survey, to conduct a comparative study of the delay factors in project completion in both Libya and UK using semi structured questionnaire and finally, to identify and analyse the causes of delay and ranked them using frequency of occurrence and severity. The critical causes of delay for construction projects were quite different between Libya and UK. For the former, the most critical causes of delay in Libyan construction industry were low skills of manpower, changes in the scope of the project, slowness in giving instruction and poor qualification of consultant, while for the latter they were financial problems, bad weather conditions on the job site and change in the scope of project. Statistical experiments including Paired Samples T-Test, was run to test the significance of the survey data in both countries Libya and UK. The statistical results confirmed the collected data from the survey were significant.

• Corrosion Science and Technology
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• 제4권4호
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• pp.155-163
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• 2005

Heavy duty coating are required to have minimum durable period of 15 years under average usage environment because these paints are coated with purpose of anti-corrosion, antifouling, plastering etc. Onto steel structures constructed upon land and sea and other ferrous structures of electric power generation plants, electricity transmission towers, large structures of various plants, etc. Therefore we tried to estimate heavy duty coating longevity through reliability evaluation method and used combined cyclic anti-conrrosion test method composed of drying, moisturizing and salt spray as for accelerated life test to estimate longevity. Accelerated life test hours to heavy duty coating of first grade (with longevity not less than 15 years) specification may be obtained from troubleless test hours $t_n=\frac{B_p}{n^{1/\beta}}\left[\frac{1n(1-CL)}{1n(1-p)} \right]^{1/\beta}=19.671$ (yr) where shape parameter $\beta=1.1$, confidence level CL=80 %, warranty life $B_{10}=15$ yr and sampling size n=10 (2 sets). Because acceleration factor {AF} found by accelerated test is 41.7, accelerated life test hours required may be represented about 4,132 hr so that if this amount of hours is converted to number of cycles(6 hr/cycle) of complex cycle corrosion resistance test then the amount is tantamount about 690 cycles. That means if there does not occur trouble failure (with defect factor sum not more than 20) during when there is performed 690 cycles of combined cyclic anti-corrosion test to heavy duty coating specimen then it signifies that there can be warranted longevity $B_{10}$ of 15 yr under condition of confidence level CL=80 %.

• 한국지반환경공학회 논문집
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• 제20권2호
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• pp.41-48
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• 2019

국내에 많은 도로공사, 공항공사, 항만공사, 구조물 되메우기 공사 등의 토목공사에서 흙의 다짐은 가장 중요한 공정 중 하나이다. 특히 도로공사에서 흙의 다짐공사는 노체다짐과 노상다짐으로 구분하며 다짐도 부족으로 부실공사의 원인으로 작용하기도 하는 중요한 작업이다. 현재는 여러 가지 다짐도 측정방법이 있으나 가장 많이 사용되는 평판재하시험이나 모래치환법에 의한 흙의 단위중량 시험방법을 가장 많이 사용하고 있으나 경제성이 없어 여러 측정방법이 개발되고 있다. 간편한 다짐도 측정 방법의 목적으로 측정기를 개발하고 제작한 것이 자유낙하 관입깊이별 다짐도 시험기(Free-Fall Penetration Test; FFPT)이다. 본 연구에서는 실내시험을 위하여 균질한 시료를 공사현장에서 확보하여 체가름 시험을 통해 흙을 분류하고 입도분석시험과 비중시험을 실시하였다. 자유낙하 관입깊이별 다짐도 시험기(FFPT)의 원리는 지구중력을 이용한 자유낙하 물체의 선단에 설치된 관입 침이 노체 또는 노상의 다짐이 완료된 노면에 관입 되는 깊이를 관측하고 그 위치에 모래치환법에 의한 흙의 단위중량시험을 통하여 다짐도 값을 구하여 분석하고 연관성을 검증하는 것으로 흙의 최대허용입경이 2.36mm로 시험하였으며 $A_1$다짐의 경우는 낙하고 10cm에서 시험한 결과 값으로 추세선을 작성하고 추세선의 결정계수 $R^2=0.8677$ 값을 도출하였으며 $D_2$다짐의 경우는 낙하고 20cm에서 측정 시 결정계수 $R^2=0.9815$ 값이 관측되었다. 자유낙하시험은 낙하높이를 10cm에서 50cm까지 10cm 간격으로 변경을 하면서 시험하였다. 본 연구는 모래치환법에 의한 흙의 단위중량시험을 통하여 얻은 다짐도 값과 FFPT 시험기를 통해 얻은 관입침의 관입깊이와의 연관성을 비교 분석하여 현재의 다짐도 측정방법의 단점인 시간, 장비, 인력의 소모를 최소화하여 경제성을 확보하고 정확성과 간편성을 보장하는 다짐도 측정기 제작으로 여러 공사현장에서 다짐도 측정이 간단하게 진행될 것이다.

• 대한토목학회논문집
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• 제30권6A호
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• pp.525-534
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• 2010

도로 경계석은 보도와 차도의 경계부에 설치하는 구조물로서 노면배수, 시선유도 등의 목적으로 사용된다. 현재 일반적인 경계석의 시공법은 경계석 기초 콘크리트를 타설한 후 콘크리트가 경계석을 지지할 수 있는 강도에 도달할 때까지 기다렸다가 경계석을 거치하고 측구 및 후면 보강콘크리트를 타설하는 공법을 사용하고 있다. 이러한 공법은 콘크리트의 분할 타설에 따른 콘크리트의 다짐 불량 및 부착강도 저하로 경계석이 차량충돌이나 토압 등에 의해 쉽게 분리되어 유지보수 비용발생과 미관을 저해하고 있다. 이러한 재래식 공법을 개선하고자 경계석과 측구를 동시에 시공할 수 있는 거푸집 레일과 지그를 이용한 일체형 시공법을 제안하였으며, 구조적 성능을 평가하기 위하여 횡 방향 재하시험, 인발 시험, 휨 시험과 같은 정적 시험을 실시하였고, 펜들럼 시험 및 실물차량 충돌 시험과 같은 동적 시험을 통한 성능평가를 실시하였다. 검토 결과 거푸집 레일과 지그를 이용한 일체형 시공법은 재래식 공법에 비해 콘크리트의 시공품질이 개선되고 부착강도가 증가하여 모든 시험에서 우수한 것으로 나타났다.