• Korean Journal of Construction Engineering and Management
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• v.13 no.1
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• pp.95-105
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• 2012

The government introduced the technical proposal drafting system in September 2007, as a new method to stimulate technical competence among construction companies to require ingenuity, creativity, artistic sense, and high-level technology. However, an examination of instances has shown that this system has been applied only to large scale constructions worth 30 billion won or more, and not to small and medium constructions worth less than 30 billion won. This is because the evaluation criteria of the system is structured in a manner that makes it difficult to apply to small and medium constructions. This study presented methods to improve the evaluation factors, categories, and scoring scheme of the technical proposal creation system for medium to small scale constructions to be able to further apply the current system to small and medium constructions. The technical proposal evaluation criteria presented in this study was significant in that it enabled the technical proposal creation system that was mainly used for large scale constructions to be further applied to medium to small scale constructions. And it also contributes to the establishment and settlement of a new technical proposal tendering for medium to small scale constructions.

• Journal of Cadastre & Land InformatiX
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• v.51 no.2
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• pp.73-82
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• 2021

According to the government's announcement of the safety management enhancement policy for small and medium-sized private construction sites, the subject of mandatory CCTV installation has been expanded from large construction sites to small and medium-sized construction sites. However, since the existing CCTV at construction sites has been used for simple control for safety management, so research is needed for monitoring of construction sites. Therefore, in this study, three vanishing points were calculated based on a single image taken with a monocular camera, and then a camera matrix containing interior orientation parameters information was determined. And the accuracy was verified by calculating the height of the target object from the height of the reference object. Through height determination experiments using vanishing points based on a monocular camera, it was possible to determine the height of target objects only with a single image without separately surveying of ground control points. As a result of the accuracy evaluation, the root mean square error was ±0.161m. Therefore, it is determined that the progress of construction work at the construction sites can be monitored through the single image taken using the single camera.

• Nuclear industry
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• v.36 no.5
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• pp.76-85
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• 2016

일반적으로 발전용 원자로의 수명은 30년부터 60년 정도로 예상하고 있다. 원자력 평화 이용 개시 초기에 건설된 발전로의 몇 기는 운전을 정지하였고, 또 사고나 경제성의 관점에서 수명이 되기 전에 운전을 정지한 발전로도 몇 기 존재한다. 전 세계에서 운전을 정지하고 폐지 조치되는 발전로는 2015년 8월 시점에서 소형의 Pilot Plant를 포함하여 156 기에 이른다. 이 중에서 현재까지 해체 완료된 발전로는 23기이며, 남은 것은 대부분 해체 중이거나 안전 저장 준비를 위한 공사 중이며 또는 안전 저장 중이다. 미국, 프랑스, 이탈리아 등에서는 운전 정지한 후의 해체 시기를 빠른 방향으로 진행하고 있다.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.30 no.4
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• pp.199-206
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• 2022

제주공항은 슬롯 증대사업을 통한 정시성 개선 노력에도 불구하고 항공 교통량의 확대에 따른 혼잡도의 증가가 지속되고 있다. 제주공항 혼잡도의 근본적인 해소를 위해서 추진되고 있는 신공항 건설이 여러 가지 사유로 지연되고 있으며, 실제 건설계획이 확정되더라도 정상적인 공항 운영까지 상당 기간의 시간이 소요될 것으로 예상된다. 따라서 제주 신공항 건설이라는 대규모 신규 투자와는 별개로 신공항 개항 전, 기존 제주공항을 운영하면서 혼잡도를 해소할 수 있는 중단기적 대안을 마련할 필요가 있다. 이에 국토교통부와 한국공항공사는 제주공항에 소형기보다는 최대이륙중량 100톤 이상의 대형항공기(통상 270석 이상 공급) 투입을 유도하는 착륙료 감면 조치를 시행하였으며, 최초 착륙료 10% 감면에서 추가 활성화를 위하여 착륙료 20% 감면으로 확대하여 운영 중이다. 항공사는 착륙료 감면 비율 상향을 통해 대형기 투입에 따른 실질적인 비용이 절감된다면 상기 정책에 적극 동참하게 될 것이다. 본 논문에서는 제주공항에서 실시 중인 착륙료 감면율 확대 조정이 항공사의 대형기 배정에 미치는 효과를 분석하여 정책의 실효성을 고찰하였으며 이에 따른 개선책을 제시하였다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.9
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• pp.240-246
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• 2019

The noise generated by construction machinery operating at construction sites is a major cause of environmental disputes with nearby residents. To reduce construction site noise, low noise construction machinery and low noise methods are recommended to be used first. In addition, the possible noise should be predicted and preventive measures suitable for the noise source should be taken. This study analyzed the sound power level of an excavator, which is used most frequently at construction sites. The sound power level of 297 excavators sold in Korea after 2008 were analyzed and the sound power level was classified according to the type, output (kW), and production site of the excavator engine based on the measured data. As a result, the sound power level decreased by 1 dBA depending on the change in engine type and the sound power level increased by approximately 3 dB (A) when the engine output was doubled. In addition, the sound power level was low in small-sized products of less than 55 kW for overseas products and medium and small-sized products of 55 to 104 kW for domestic products.

• Proceedings of the Korea Water Resources Association Conference
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• 2018.05a
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• pp.236-236
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• 2018

한국농어촌공사 농어촌연구원에 구축되고 있는 대형 수리모형 실험시설은 수공구조물에 대한 수리모형실험 수행, 설계기준 제 개정, 호안 검인증제도 지원 등 국가의 정책지원과 개방 공유를 통한 국내 건설기업의 하천분야 신기술 개발 및 국가 경쟁력 확보, 하천 관련 원천기술 확보 등 다양한 목적을 가지고 진행되고 있는 대규모 분산공유형 실험시설에 해당한다. 본 사업의 일환으로 현재 구축 진행되고 있는 7종의 실험수로는 장기하상변동, 토석류, 실규모 호안블록, 감세공 수리특성, 신형어도개발 등 다양한 수리특성에 대한 계측 및 분석이 가능한 대형 실험시설에 해당한다. 7종의 실험수로는 PIV시스템의 연계 계측이 가능한 1) 고정식개수로, 2) PIV실험수로와 1/5의 역경사 재현이 가능한 3) 가변식경사수로, 호안블록 및 사석의 소류력 측정이 가능한 4) 고정식급경사수로, 토석류흐름 측정이 가능한 5) 가변식하도실험수로, 장기하상변동 분석을 위한 6) 대형유사순환수로, 부유사의 침 퇴적 양상 재현을 위한 7) 소형유사순환수로로 구성되어진다. 7종의 실험수로는 '18년 2월에 착공하여 현재 실시설계도서를 검토 중에 있으며, 18년 9월에 준공될 예정이다.

• Korean Journal of Construction Engineering and Management
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• v.15 no.5
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• pp.138-146
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• 2014

Modular construction is one of the arising issues in the Korean construction industry due to shorter construction period and higher productivity on site. It is also expected that modular construction market would expand rapidly because of increasing demand of small houses by nuclear families and eco-friendly construction. However modular construction cases have been limited in Korea because of little demand in the market and the construction prices are even higher that the regular reinforced concrete methods. Even worse, because there is no standard bill of services exists in the industry, it may lead to the risk of construction expenses. So, the purpose of this study is focused on the development of bill of services which reflects characteristics and process of modular construction. In order to do this, the concepts and process of modular construction, WBS and CBS are analyzed. Analyses of the case studies and experts interview were executed so that proper principles for organizing bill of service of modular construction is established. Finally according to the 3 steps of modular construction, factory manufacturing, on-site modular construction and on-site general construction, the standard bill of services were suggested with the related coding system.

• International Journal of Highway Engineering
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• v.13 no.2
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• pp.57-65
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• 2011

In this study, estimated the minimum lane width for the curved section by analyzing of lateral sway distance and compared the lane width for result of this study and a precedent study for straight section on urban roads. Then suggested minimum lane width of road alignments and vehicle classes. The lane width of curved section that was investigated was 2.79m~3.40m. Analysis of frequency distribute and cumulative frequency distribution for lateral sway distance on the basis of 85% of the suggested vehicles. The result of study, minimum lane width for the curved section was 2.31m~2.58m in the case of small size car and 2.80m~3.27m in the case of large size car. Result of this study is judged that it is necessary to case for introduction of green transit, during road construction and construct a road for small size car. Expect result of this study can be used for the application of flexible design standard according the purpose of road designer.

• Journal of Cadastre & Land InformatiX
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• v.47 no.1
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• pp.111-126
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• 2017

Small-scale UAS(Fusion technique of Unmanned Aerial Vehicles platform and Sensors, 'sUAS') opens various new applications in construction fields and so becoming progressively common due to the considerable potentials in terms of accuracy, costs and abilities. The purpose of this study is that the investigation of the validation on the utilization of sUAS for earth stockpile volume calculations on sites. For this, generate 3D models(DSM) with sUAS aerial images on an cone shaped soil stockpile approximately $270m{\times}300m{\times}20m$, which located at Baegot Life Park in Siheung-si, compared stockpile volume estimates produced by sUAS image analysis, against volume estimates obtained by GNSS Network-RTK ground surveying method which selected as the criteria of earth stockpile volume. The result through comparison and examination show(demonstrate) that there was under 2% difference between the volume calculated with the GNSS Network RTK data and the sUAV data, especially sUAS imaged-based volume estimate of a stockpile can be greatly simplified, done quickly, and very cost effective over conventional terrestrial survey methods. Therefore, with consideration of various plan to assess the height of vegetation, sUAS image-based application expected very useful both volume estimate and 3D geospatial information extraction in small and medium-sized sites.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.44 no.1
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• pp.109-116
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• 2024

The Rapid Hardening Composite Mat (RHCM) is a product that improves the initial strength development speed of conventional Geosynthetic Cementitious Composite Mats (GCCM). It offers the advantage of quickly securing sufficient strength in railway slopes with insufficient formation level, and provides benefits such as preventing slope erosion and inhibiting vegetation growth. In this study, an analysis of the practical applicability of RHCM in railway settings was conducted through experimentation. The on-site applicability was assessed by categorizing it into fire resistance, durability, and stability, and conducting combustibility test, ground contact pressure test, and daily displacement analyses. In the case of South Korea, where a significant portion of the territory is composed of forested areas, the prevention of slope fires is imperative. To analyze the fire resistance of RHCM, combustibility tests were conducted as an essential measure. Durability was assessed through ground contact pressure tests to analyze the deformation and potential damage of RHCM caused by the inevitable use of small to medium-sized equipment on the construction surface. Furthermore, daily displacement analysis was conducted to evaluate the structural stability by comparing and analyzing the displacement and behavior occurring during the application of RHCM with railway slope maintenance criteria. As a result of the experiments, the RHCM was analyzed to meet the criteria for heat release rate and gas toxicity. Furthermore, the ground contact pressure was observed to be consistently above 50 kPa during the curing period of 4 to 24 hours under all conditions. Additionally, the daily displacement analyzed through field site experiments ranged from -1.7 mm to 1.01 mm, confirming compliance with the criteria.