• Korean Journal of Construction Engineering and Management
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• v.13 no.1
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• pp.106-117
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• 2012

The proportion of rebar factory manufacturing which has been settled down in Korea recently seems to increase because of their strength such as high decreasing rate of rebar loss and manufacturing accuracy and the external factors such as an increase of downtown projects and a decrease of skilled workers. However, factory manufacturing using straight rebars causes a certain amount of rebar loss and an environmental problem including $CO_2$ emissions. To solve these problems, Bar in coil (BIC) has been introduced; however its application is very rare because it has not been produced so far in Korea and manufacturing machines of BIC are very expensive. Also, although BIC's application is expected to expand due to its strengths, few analysis of its application has been conducted. Therefore in this study, analysis of the BIC's characteristics and the influence to the rebar manufacturing industry are conducted for the advancement of rebar work as a basic research. To achieve this, inquiry on the present condition of rebar manufacturing industry in Korea is implemented. Then, the validation of BIC's applications by aspects of industry and the analysis of stakeholders' economical profit and loss are conducted.

• Proceedings of the Korea Water Resources Association Conference
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• 2016.05a
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• pp.213-213
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• 2016

수문조사기기의 검정은 수문조사에 활용할 기기를 일관되고 표준화된 기준으로 검사하여 수문조사에 적합한 기기인지 확인하는 것이다. 이러한 검정은 국가수문자료의 신뢰도를 높이고 유지하는 기본적이고 중요한 업무이다. 검정대상기기는 강수량측정기기, 유속측정기기, 수위측정기기, 부유사측정기기, 토양수분측정기기, 증발산량측정기기로 총 6가지이며, 2009년부터 국토교통부 위탁사업으로 한국건설기술연구원(유량조사사업단)에서 수행하고 있다. 특히 유량조사사업단에서는 유속측정기기를 제외한 나머지 5개 수문조사기기에 대해 검정을 수행하고 있다. 연도별로 2009년부터 2015년까지 98대, 334대, 572대, 539대, 359대, 682대, 690대로 총 3,274대를 검정하였고, 관측기종별로 강수량 1,579대, 수위 1,589대 부유사 23대, 토양수분 33대, 증발산량 50대이다. 신청기관별로는 국토교통부(홍수통제소) 1,847대, 환경부(국립환경과학원) 4대, 한국건설기술연구원(유량조사사업단 포함) 81대, K-water 338대, 한국수력원자력(주) 91대, 일반업체 913대에 대한 검정을 실시하였다. 검정을 실시한 강수량측정기기 1,579대 중 보정없이 합격된 기기는 1,495대, 허용오차기준에 미달되어 보정 실시 후 합격한 기기는 76대이며, 불합격 처리된 기기는 8대이다. 수위측정기기는 합격이 1,586대, 기준에 미달되어 불합격된 기기가 2대로 나타났다. 강수량측정기기의 각 연도대비 통계분석 결과 보정률은 2009년 97대 중 8대(8.2%), 2010년 194대 중 3대(1.5%), 2011년 180대 중 24대(13.3%), 2012년 175대 중 17대(9.7%), 2013년 165대 중 15대(9.1%), 2014년 547대 중 8대(1.5%), 2015년 221대 중 9대(4.1%)로 다소 낮은 수치로 나타났다. 이처럼 보정률이 낮게 나타난 이유는 관할기관의 검정을 위한 유지관리 및 사업자의 사전검사 등을 통해 감소한 것으로 판단되며, 이와 같은 결과는 수문자료의 품질 및 신뢰도 향상으로 이어졌다. 그러나 여전히 선진국에 비해 수문조사기기 검정의 중요성에 대한 인프라 구축이 미흡한 실정이다. 수문조사기기 검정의 선진국이라 할 수 있는 미국의 경우 USGS에서 HIF(Hydrogical Istrumentation Facility)라는 별도 조직을 운영하여 관측기기의 렌탈, 수리, 교정 및 검정, 개발, 교육 등 이러한 작업을 일괄 수행하고 있고 조직 내 자체 시설로 수중펌프 시험소, 자연과 유사한 환경에서 테스트 하는 장소, 대형온도챔버 등을 갖추고 있으며, 이러한 시설을 이용하여 기기의 교정 및 검정, 연구 등을 현장과 비슷한 환경에서 다양한 실험을 통해 검정방법을 비교, 분석하는 것을 볼 수 있다. 현재 우리나라의 수문조사기기는 다양한 방법으로 현장에 설치되어 검정방법의 다양성이 요구된다. 향후 우리나라도 HIF와 같이 다양하고 선진화된 시설과 기술을 개선하고 다각적인 시험 과정을 통해 수준 높은 검정방법체계를 갖추려는 노력이 필요하다.

• Journal of KIBIM
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• v.1 no.2
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• pp.19-23
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• 2011

The planning stage of an architectural project has much more significant effects on the cost or outcome of the project than other stages of the project. In addition, the importance of architectural planning has been further increasing according to the recent trend of construction projects becoming larger in scale and more complex. In spite of this, the current situation is that the planning stage work is not being systematically managed. Accordingly, the purpose of this study was to develop a BIM-based simulation system for providing support during architectural planning stage such as spatial planning & review, cost review, project owner requirements management, etc. It is easy to review various alternatives using this system that allows not only the modeling of space object modeling but also the instantaneous review of spatial area & layout, cost, etc. based on object information. In addition, it can be used as a communication tool with the project owner as it provides the visualized information and quantitative data of the building model, and the information created through this system can be delivered to the following stage for usage. It is thought that using this system, the entire project work including the architectural planning stage can be supported and even contributing to the advancement of architectural process.

• Journal of the Korean Geotechnical Society
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• v.38 no.12
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• pp.91-101
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• 2022

The 1995 Kobe earthquake caused a massive damage to the Port of Kobe. Therefore, it was pointed out that it was impossible to design port structures for Level II (Mw 6.5) earthquakes with quasi-static analysis and Allowable Stress Design methods. In Japan and the United States, where earthquakes are frequent, the most advanced design standards for port facilities are introduced and applied, and the existing seismic design standards have been converted to performance-based design. Since 1999, the Korean Port Seismic Design Act has established a definition of necessary facilities and seismic grades through research on facilities that require seismic design and their seismic grades. It has also established a performance-based seismic design method based on experimental verification. In the performance-based seismic design method of the breakwater proposed in this study, the acceleration time history on the surface of the original ground was subjected to a fast Fourier transform, followed by a filter processing that corrected the frequency characteristics corresponding to the maximum allowable displacement with respect to performance level of the breakwater and the filtered spectrum. The horizontal seismic coefficient for the equivalent static analysis considering the displacement was calculated by inversely transforming (i.e., subjected to an inverse fast Fourier transform) into the acceleration time history and obtaining the maximum acceleration value. In addition, experiments and numerical analysis were performed to verify the performance-based seismic design method of breakwaters suitable for domestic earthquake levels.

• Korean Journal of Construction Engineering and Management
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• v.6 no.2 s.24
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• pp.120-128
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• 2005

ISO 9001, the quality management system issued by the International Organization for Standardization, is being used by architectural design and engineering firms in order to strengthen the capability of business activities through the implementation of the international and advanced quality management systems. However, there have been significant problems in stable implementation and settlement of ISO 9001 in construction industry, which seem to be caused by key employees' lack of proper recognition and comprehension. The purpose of this research, accordingly, is to find and analyze nonconformity results which were found when the third party registrars audited the conformity of companies' quality management systems for ISO 9001 certification especially in architectural design and engineering firms. For this purpose this research was conducted by a cluster analysis of 647 audit reports out of representative 15 architectural design and engineering firms that have been audited periodically from 1997 to 2003 by the third party registrars. The analysis showed that the most frequent problems were generated in the areas of $\ulcorner$Design and Development$\lrcorner$ , $\ulcorner$production and Service Provision$\lrcorner$ , and $\ulcorner$General requirements$\lrcorner$ of the quality management system. The following, the areas of $\ulcorner$Monitoring and Measurement$\lrcorner$ and $\ulcorner$purchasing$\lrcorner$ were also analyzed as main factors which caused frequent nonconformity results. This research also shows that the corrective actions for nonconformity results are closely connected with the whole management activities in architectural design and engineering firms. Consequently, corrective actions for disposition of nonconformities should be implemented more specifically in order to settle and activate the quality management systems in architectural design and engineering firms.

• Journal of Korean Society of Transportation
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• v.33 no.4
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• pp.337-347
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• 2015

Since the application of roundabouts by 2010 have been started, more than 350 roundabouts were installed in Korea. Recently the types of constructed roundabouts become various, and the intersection conditions for installing roundabouts were also various. However, there were some difficulties to install roundabouts around school zone due to safety problems. In this study, appropriate distance from adjacent signal crosswalks to roundabouts were estimated for securing pedestrian safety and operation efficiency around school zone. With the analyses, the minimum distance standard was suggested to obtain operational effectiveness of roundabout according to traffic volume, traffic flow, pedestrian green time and secures pedestrian safety and convenience. In this paper, average delay of roundabout as various length of distances between an adjacent crosswalk and a roundabout as different pedestrian signal times, traffic volumes, traffic flow rates were analyzed. Through this study, it was found that about four times of delay in a roundabout was generated if there was adjacent signal crosswalk. However if there is enough distance between an adjacent crosswalk and a roundabout, the value of increasing delay on roundabouts with adjacent a signalized crosswalk can be considerably reduced. Critical value of the distance between a roundabout and a signal crosswalk in case of roundabouts within 200-500 vehicle/hour/lane entry traffic flow, 20-40% of left turn traffic, and over 15 seconds pedestrian green time was about 50 meters. In conclusion, if there is minimum 40 meter distance from roundabouts, adjacent signal crosswalks can be installed and operated for students' safety around school zone.