• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.09a
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• pp.326-329
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• 2004

The groundwater system of the Cheonggyecheon watershed is very complicated because it is influenced by many factors such as pumping out, groundwater leakages into subway stations, civil use of groundwater, and leaking water from water supply and sewage lines. So the characterization and evaluation of the groundwater flow and contaminant transport in the Cheonggyecheon water system is quite a difficult task. The purpose of this study is to analyze the influence on the‘groundwater’ below the Cheonggyecheon watershed by the‘maintenance water’on the Cheonggyecheon stream after the restoration. We have so far collected groundwater quality data, hydrogeologic aquifer parameters, and the amount of leakages into subway stations and its influence on the groundwater system. Results show that groundwater level was influenced by the direction and depth of subway tunnel. This study will continue to monitor groundwater quality, a water level fluctuation relation between rainfall and groundwater recharge for further investigation of the groundwater flow system in the Cheonggyecheon watershed.

• Journal of Korean Tunnelling and Underground Space Association
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• v.24 no.6
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• pp.715-724
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• 2022

With the enforcement of the infrastructure management act, the importance of utility tunnels that jointly accommodate life-lines such as electricity, communication, water supply, and heating facilities has increased. The currently applied utility tunnel maintenance system is managed in an accident-preventive safety-based evaluation method. However, this evaluation method has limitations in effective maintenance. In this study, performance evaluation items were derived through the Delphi method to suggest a criterion for quantitatively evaluating the performance of utility tunnels, and the weights for each item were calculated through the Analytic Hierarchy Process (AHP) method. In the future, it is judged that a more reasonable performance evaluation standard of utility tunnel can be prepared if modifications and supplements are made through field application.

• Tunnel and Underground Space
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• v.13 no.4
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• pp.260-269
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• 2003

In order to introduce to engineers the suitable calculation techniques of TBM advance rate (ad.) and ultimately promote to understand the designing process, this study was carried out. We analyzed the 17 bored data of TBM which applied to the roadway and water supply tunnels in Korea. From this analysis, it was able to how that the average utilization is 30.83% md the correlation equation of Ad and TBM´s diameter (D) is Ad(m/month) = 506.05ㆍ $e^{-0.1162}$$\times$D than the correlation coefficient ($R^2$) is 0.76. In the object of the W tunnel of Seoul-Busan highspeed railway, the Ad of TBM 5.0mø was analyzed by the variety of empirical models and upper correlation equation. Average Ad of the empirical models was calculated to be larger than one of the upper equations. But considering only the results of 3.0~5.0mø TBM in the 17 bored data, the average Ad by the models belongs to the similar range of bored data. Therefore, when the reliability and representative of parameters are decreased, a reliability test should be carried out through the comparison a variety of empirical models with the upper correlation equation.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.11a
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• pp.764-767
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• 2010

The high enthalpy plasma research center in Chonbuk national university is under construction for MW class plasma wind tunnel. Four types of plasma equipment will be installed in the research center. The equipments are 1set of 0.4 MW class enhanced Huels type plasma equipment, 1 set of 2.4 MW class enhanced Huels type plasma equipment, 1 set of 60 kW RF plasma equipment and 1 set of 200 kW RF plasma equipment. And electrical, water and gas utilities to assistant plasma equipments are under construction. The research center consists of experiment building, research building, power supply building, air supply building, cooling tower foundation.

• Journal of the Korean Geotechnical Society
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• v.37 no.10
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• pp.55-63
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• 2021

The construction of shield tunnels is being expanded from the small-bore tunnels such as power, telecommunications, water supply, and sewerage pipes to the large bore tunnels such as road and railway tunnels with the advancement of the shield TBM (Tunnel Boring Machine) manufacturing technology. Accordingly, the construction of twin shield tunnels is increasing. Peck (1969) reported that the surface settlement trough is well described by a Gaussian distribution on a single shield tunnel. Hereafter, many studies about the surface settlement trough were performed by the field measurement, laboratory model test, and numerical analysis. This study confirmed that the additional surface settlement trough induced by the 2^nd tunneling were well described by using each Gaussian curve for the right and left sides of the settlement trough.

• Journal of The Geomorphological Association of Korea
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• v.18 no.1
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• pp.1-13
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• 2011

The catch canal for a natural drainage, the excavation of tunnel for a stable irrigation, the artifical channelization of yazoo stream, many kinds of the pumping and drainage systems are found around Daedong-myeon, Gimhae-si. It could be confirmed that the deveolpment, maintenance and management of those facilities in the floodplain are mainly controlled by the geomorphological conditions. In case of Unha-chon, especially, the water can always be supplied only by openning the gate of irrigation tunnel and the Woldang pumping station as the largest pumping station in this area can supply water to Unha-chon area directly from the main river, Nakdong-gang. Because the Gamnae-chon which was an upper reach of the Unha-chon and is now connected to the Nakdong-gang through the Deoksan catch canal, the damage of flood and the burden of drainage are mitigated at the lower area of the Unha-chon.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2004.04a
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• pp.139-144
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• 2004

This study aims to analyze the accuracy of rover speed change in route surveying using RTK-GPS. Route surveying methods using GPS contain Static, DGPS, and RTK-GPS. Much research of navigation system, positioning of vehicles by DGPS, and accuracy analysis by GPS surveying have already been done. From this study, it is firstly found that DGPS is suitable for car navigation and sea navigation with an error of meter scale but not good for detailed construction, designing maps and updating GIS databases. Secondly, RTK-GPS can be used for managing gas pipes, water supply and drain pipes and fiber-optic cable that are needed to be controlled in a real time basis. Thirdly, since the accuracies of route surveying by RTK-GPS and DGPS are not correctly matched with the change of rover speed, the choice of route surveying method from those two should follow the need of accuracy fidelity Further study should focus on Cycle Slip problem and coordinate change problem in tunnel and mountainous areas.

• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.626-629
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• 2008

Numerical predictions on flow phenomena in pipe network systems have been considered as playing an important role in both designing and operating various facilities of piping or duct systems, such as water supply, tunnel or mine ventilation, hydraulic systems of automobile or aircraft, and etc. Traditionally, coupling conditions between junction and connected branches are assumed to satisfy conservation law of mass and to share an equal pressure at junction node. However, the conventional methodology cannot reflect momentum interactions between pipes sufficiently. Thus, a new finite volume junction treatment is proposed both to reflect the interchanges of linear momentums between neighbor branches at junction and to include the effect of wall at junction in present work.

• Journal of Environmental Impact Assessment
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• v.6 no.1
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• pp.151-160
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• 1997

The Yangyang Pumped Storage Power Plant is being constructed by Korea Electric Power Corporation in Namdae-Chun River, Korea. The Yangyang Pumped Storage Power Plant has 1000MW capacity with upper reservior, lower reservior, hydrauric tunnel and underground power plant facilities. But NGO(Non Governmental Groups) and residents are worried about the power plant construction because of some problems, as follows. (1) Namdae-Chun River is principal salmon returning river in Korea. (2) Namdae-Chun River is main water supply source of the Yangyang country. So, brief explanation of Environmental Impacts Assessment executed by Korea Electric Power Corporation, main environmental impacts and countermeasures will be introduced.

• Journal of Korean Society for Geospatial Information Science
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• v.4 no.2 s.8
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• pp.55-61
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• 1996

The objective of this paper is to show an optimal design model for branched water supply system which also can find the optimal location of pumping stations using linear programming. GIS is utilized in this model to better handle the data and the results front the optimization. The developed model considers hydraulic influences of some appurtenances such as supply tunnels and a filtration plant The model also considers tunnel construction cost which should be treated differently from pipe construction cost Different from other models presently available, the model guarantees a nonnegative pressure at every junction node in the system. The objective function includes annual operation cost (electricity rate) ill addition to initial construction cost, thus producing a more reasonable decision. The model selects the optimal diameter not in the form of continuous number but in the form of commercial discrete diameter (pipe size) using the pipe lengths as decision variables instead of pipe diameters. The model not only determines the optimal pumping head for each pumping station but also finds the optimal location and number of pumping stations. GIS is used to handle hydraulic and budgetary data automatically and to visualize the results for the of optimal design of the system. The model has been applied to an existing water supply system. 'The results show that the optimization model with the aid of GIS is helpful in the decision-nulling process for the design of more economical systems, and can be dot into practice successfully.