• 상하수도학회지
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• 제25권2호
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• pp.213-221
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• 2011

The purpose of sewer system is to separate rain water from sewage water. Through this, it is possible to prevent the flood and preserve public water territory. For the past few years, many problems of the sewer system have been solved by the execution of sewer rehabilitation project. However, they still exist in sewer system caused by I/I, which are divided into infiltration and inflow. Infiltration means the rain water and underground water that infiltrate through breakage point on pipes, inflow means the water that flows in through misconnection on pipes. This study shows how the I/I calculation has changed according to the new standardized manual and identifies the I/I difference between the new calculation and the existing one. Through the analysis on the two calculation methods we examined the appropriacy of the new method by comparing it to the old one. The result points out that the new standardized manual is more appropriate than the old in aspect of objectivity and reproducibility(establish standardization), rationality(alteration of inflow unit).

• 대한토목학회논문집
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• 제35권1호
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• pp.217-227
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• 2015

본 연구는 건설투자 GDP (Gross Domestic Product) 디플레이터 방식의 물가조정이 이루어진 제주특별자치도 내 하수관거정비 BTL(Build-Transfer-Lease)사업에 대하여 물가변동률 적용에 문제점을 파악하기 위하여 실시되었다. 분석 결과, GDP 디플레이터 방식의 기준지수는 고정값을 사용하며 매분기별 물가변동률이 반영되기 때문에 지수조정률 방식보다 물가변동률이 높게 나타나는 것으로 조사되었다. 그러나 GDP 디플레이터 지수가 총사업비에 일괄적으로 적용되기 때문에 현실적인 물가를 반영하지 못함으로써 정확도가 떨어지는 단점이 있는 것으로 조사되었다. 또한 GDP 디플레이터 방식의 기준지수가 고정값을 사용하기 때문에 기준이 되는 시점(정부고시일)이 물가조정에 매우 크게 영향을 미치는 것으로 조사되었다.

• 상하수도학회지
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• 제22권6호
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• pp.647-655
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• 2008

Sewer Rehabilitation Project (SRP) is planed, designed and constructed to perform its intended performance as sewerage delivery systems. Recently, a subject of performance evaluation methodology development for SRP has become a great deal of concern among researchers in Korea. From the view point of Sewage Treatment Plant (STP), however, the estimation of improvement efficiency for SRP is in lack of reliability due to the fact that affections for the treatment efficiency and operating condition are not reflected on SRP design and construction. In this study, statistical methodology was used in the analysis of data, which are taken during 1,186 days ($1^{st}$ Jan. 2005 - $31^{th}$ Mar. 2008) from the influent, effluent and operating conditions of full-scale STP($25,000m^3/d$). Then the effect of SRP on the influent characteristics and operating conditions changing was compared and evaluated. Results from the statistical evaluation show that SRP causes characteristic changes in influent and exerts a significant effect especially on the performance of STP.

• 상하수도학회지
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• 제32권2호
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• pp.169-181
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• 2018

For performance analysis of flood prevention projects, this study performed simulation (SWMM) for the five sites where the projects have been completed. The models were constructed using watershed and sewer information of the project sites and were verified using flood records in the past to improve accuracy. In this simulation, the design rainfall data (probability 30~50 years) and the rainfall data in the summer of 2017 were applied. When the design rainfall data was applied to the models, simulation results presented that all the sites were flooded before the projects, but after the projects all the sites were not flooded due to improve discharge capacity. And when the rainfall data in the summer of 2017 was applied to the models, simulation results presented that all the sites were flooded before the projects, but after the projects any sites did not occur flooding in this summer. So if the projects had not been completed, all the sites might be flooded in the summer of 2017. These effects were analyzed as the improvement of discharge capacity due to rehabilitation of sewer, construction of underground tunnel and pumping station, etc. As the results, ratio of sewer that water depth exceed diameter reduced from 52.3~75.8% to 17.1~39.8%.

• Journal of Construction Engineering and Project Management
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• 제2권1호
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• pp.35-44
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• 2012

In the last two decades, several tele-operated and machine-vision-assisted systems have been developed in the construction and maintenance area, such as pavement crack sealing, sewer pipe rehabilitation, and excavation. In developing such tele-operated and machine-vision-assisted systems, trajectory plans are very important tasks for the optimal motions of robots whether their environments are structured or unstructured. This paper presents an optimal trajectory planning algorithm used for a machine-vision-assisted automatic pavement crack sealing system. In this paper, the performance of the proposed optimal trajectory planning algorithm is compared with the greedy trajectory plans, which are used in the previously developed pavement crack sealing systems. The comparison is based on the computational cost vs. the overall gains in crack sealing efficiency. Finally, it is concluded that the proposed algorithm plays an important role in the productivity improvement of the developed automatic pavement crack sealing system.