• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.100-100
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• 2011

포항가속기연구소에서는 제3세대 방사광가속기 성능향상사업(PLS-II)을 수행하고 있다. 2010년 12월 말 PLS (Pohang light Source) 해체를 시작한 후 2011년 6월 말 까지 PLS-II 저장링 건설을 완료 하였으며 현재 시운전을 계속하고 있다. 성능향상은 기존 PLS 건물을 그대로 유지한 채 삽입장치를 20기 까지 설치하도록 변경하도록 하였으며 전자빔의 에너지는 2.5 GeV에서 3 GeV로, 빔전류는 200 mA에서 400 mA로 증가시키는 반면 빔에미턴스는 약 1/3로 줄인다. 저장링 진공시스템은 저장된 전자가 충분한 시간동안 저장되도록 운전시 2${\times}$10-9 Torr 이하의 진공도를 가지도록 건설하였다. 본 발표에서는 지난 2년 동안 진행되어온 PLS-II 저장링 진공시스템에 대한 설계, 제작, 시험, 설치, 시운전 및 건설 일정/인력에 등에 대하여 보고하며 PLS 건설 및 해체에 대한 내용도 보고한다.

• Journal of the Korean Geotechnical Society
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• v.39 no.12
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• pp.103-114
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• 2023

Monitoring the site of an underground construction wall is crucial to confirm the stability of the supports and ground due to excavation. In particular, it is essential to maintain the accuracy of a load cell gauge, which identifies the load of the support transmitted from the excavated ground. However, research on verification methods and regulations that can identify the accuracy of load cell gauges at construction sites is inadequate, which is a problem as load cell gauges are installed without proper performance inspections. In this study, performance tests were conducted by a complete investigation of load cell gauges sold in Korea and comparing them with foreign products to determine defect causes. In addition, the criteria for selecting a load cell gauge were presented, and the results of this study were considered to help select a highly reliable load cell gauge.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2007.11a
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• pp.527-530
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• 2007

The construction market has gradually become complexity, variety and specialization, and then owner's requirements about quality has become various. In order to solve the problem such as stated above, advanced constructions in France, United Kingdom, Japan and United States have introduced warranty contract which is warranted to quality and performance for need of owner in determined term to ensure the quality of construction since 1960s. In addition to, domestic constructions have been meeting with international competition because of the open BOT market from FTA. Finally, this study proposed new warranty delivery system model in PFI on considering domestic status by benchmarking the delivery process and the characteristics of the warranty contract which is applied to PFI of global.

• Proceedings of the Korea Water Resources Association Conference
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• 2017.05a
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• pp.325-325
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• 2017

빗물펌프장은 도시지역 저지대의 우수를 강제로 배출하여 제내지의 치수안전도를 향상시키기 위한 방재시설이다. 변화하는 기상조건에 맞추어 침수취약지역의 치수안전도를 유지 또는 향상시키기 위해서는 빗물펌프장 설계시 목표한 치수성능을 지속적으로 구현할 필요가 있다. 그러나, 펌프시설의 고속운전, 변화하는 펌프운영조건 등의 영향으로 펌프의 성능은 지속적으로 저하된다. 이와 같은 펌프성능의 주요원인은 펌프운영시 발생하는 공기연행이 주요 원인중 하나이다. 흡수정 설계단계에서는 와류에 의한 공기연행을 제어하기 위하여 흡입관경, 흡수정 벽면으로부터의 이격거리 등의 설계요소를 반영하고 있지만, 도심지역의 제한적인 공간특성으로 인하여 설계기준치를 만족하지 못하는 경우가 발생하게 된다. 설계시 흡수정 내에 형성되는 와류를 억제하기 위하여 흡수정의 벽면 모서리를 완만하게 시공하거나, 흡수정 내에 날개벽 또는 별도의 시설을 설치하는 방법을 채택하고 있다. 그러나, 이와 같은 와류방지시설은 고정된 설계조건에 대하여 성능구현이 가능하지만, 홍수시 흡수정 내의 흐름은 하천의 수위 및 유입되는 유량에 의하여 시시각각 변화하게 된다. 이와 같은 운영조건의 변화에 대응할 수 있는 방법을 제시하기 위하여 본 연구에서는 수면에 부유식 와류방지장치를 설치하고 이에 대한 성능을 3차원 수치모의를 통하여 재현한 후 정량적으로 분석하였다. 부유식 와류방지장치에 대한 성능검토결과, 다양한 운영조건에서도 부유식 와류방지장치가 유효한 와류저감효과를 구현하고 있는 것을 확인하였다.

• Journal of the Korea Institute of Building Construction
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• v.10 no.1
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• pp.175-180
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• 2010

Despite continuous efforts by the construction industry to achieve better quality, it doesn't seem that much has been improved. This is mainly because current specifications do not satisfy a change in the market environment, which is that a higher level of quality is now demanded by users. Quality improvement efforts have been satisfied merely to meet specifications. On the other hand, advanced countries have been experienced great success in their construction techniques and have reduced costs by introducing apay adjustment system to the construction industry, in which compensation is based on performance. Following their example, Koreashould introduce such a pay adjustment system in order to motivate the members of our construction industry to achieve better quality and a higher level of construction techniques. However, there has been a lack of a rational approach to the development of a system for cost coordination, as well as performance and quality inspection. Thus, in this study a legal and logical plan was developed that can be used to adjust the construction cost, along with the performance inspection of quality results, in order to introduce a pay adjustment system that is appropriate for domestic regulations.

• Journal of the Korea Institute of Building Construction
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• v.21 no.5
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• pp.397-408
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• 2021

The construction industry has the highest occupational accidents/injuries and has experienced the most fatalities among entire industries. Korean government installed surveillance camera systems at construction sites to reduce occupational accident rates. Construction safety managers are monitoring potential hazards at the sites through surveillance system; however, the human capability of monitoring surveillance system with their own eyes has critical issues. A long-time monitoring surveillance system causes high physical fatigue and has limitations in grasping all accidents in real-time. Therefore, this study aims to build a deep learning-based safety monitoring system that can obtain information on the recognition, location, identification of workers and heavy equipment in the construction sites by applying multiple object tracking with instance segmentation. To evaluate the system's performance, we utilized the Microsoft common objects in context and the multiple object tracking challenge metrics. These results prove that it is optimal for efficiently automating monitoring surveillance system task at construction sites.

• Magazine of RCR
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• v.12 no.1
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• pp.23-30
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• 2017

• 월간 기계설비
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• no.9 s.194
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• pp.86-86
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• 2006

• Construction Engineering and Management
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• v.17 no.6
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• pp.31-34
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• 2016

• Construction Engineering and Management
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• v.5 no.5 s.21
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• pp.21-27
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• 2004