• Korean Journal of Agricultural and Forest Meteorology
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• v.1 no.1
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• pp.36-40
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• 1999

A new method was developed to measure underground water level with high reliability. The principle of new method was to detect a change of a buoyant force according to change in water level of underground water measured by the use of a straingage load cell. Field test of the instrument was carried out in Cheju Island. The results were as follows; 1) The present study provided a possibility to develop a new underground water level meter. 2) This new instrument accomplished high reliability at field test in Cheju Island. 3) There is possibility of development of water level meter which measure various range of water level to detect a weight change of a buoyant forcd.

• Journal of the Korean Society of Industry Convergence
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• v.8 no.3
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• pp.161-168
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• 2005

This study is analysis for adjacent structures and ground movement by deep excavation work. Underground Inclinometer has shown that deformation of increment is minor within to allowable limit. According to the measurements result of slope and crack for adjacent structures, a detached house showed bigger than hospital structure to deformation of increment. Variation of underground water level didn't effect so much to ground and adjacent structures movement because underground water flows in rock and didn't give the water press to propped walls. Measurement data of strut variation is within tolerance limit. Because excavation site's wall was strengthened suitably. This study will contribute in establishment of measurement standard and information-oriented construction during deep excavation in multi-layered ground including rock masses.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.904-909
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• 2008

Most of current slope safety analysis consider only the effect of the rise of underground water level. However, because the infiltration of surface water into the ground is believed to have signification effect on slope stability, the present study performed slope safety analysis in case of the rise of underground water level, infiltration of surface water, and both resulting from rainfall, and examined their effect.

• Journal of the Korean GEO-environmental Society
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• v.16 no.9
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• pp.13-21
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• 2015

Recently, land subsidence and sinkhole are generated due to a change in the groundwater level in the city. For this reason, the necessity for management of stable underground water level is on the rise. In this study, it was conducted for the underground structure that passes through the lower of bus transfer center construction site to examine the influence on the stability for underground structures to changes in the groundwater level and effective stress, the coupled finite element analysis and structural analyses were performed to evaluate stability for underground structure. It is to secure stability for underground structures according to underground water level declines. In this way, effective construction management will be made by previewing and forecasting the influence on the ground behavior and adjacent structures due to changes in the groundwater level.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.11a
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• pp.181-183
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• 2011

This study was carried out about construction management plan to reduce water leakage of underground parking lot in the apartment housing. To minimize effect of upper working load, installation position of jack support and paving with rubble on the top of underground parking lot were studied. By calculation shrinkage strain of underground parking lot scale, water leakage risk in design of level difference was studied. In this study, the basic data about construction management was provided to reduce water leakage of underground parking lot in the apartment housing.

• Journal of the Korea Society of Computer and Information
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• v.12 no.4
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• pp.229-237
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• 2007

To solve of complex problems for access and management data stored in the very large spatial database system that need to constructed metadata for the physical and logical elements concerned with spatial and non-spatial data sets. Also, in the underground water management system which managed with spatial and non-spatial elements, need to spatial features metadata system based on feature-based. We, in this paper, proposed metadata model for the feature-based underground water management system using underground water meta-information inputted on the DXF formatted tile-based geological maps. Additional, we modeled metadata level of feature and data set and presented standard specification of underground water metadata.

• Journal of Korean Society on Water Environment
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• v.21 no.1
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• pp.52-58
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• 2005

The assessment on characteristics of hydraulic behavior and water quality variations of underground reservoirs of buildings were studied. Firstly, it was thought that underground reservoir capacities($m^3$) of buildings should be not determinated by the uniform and same methods but be estimated on the basis of the dwelling areas on dominated households and their residential characteristics, because these characteristics influence significantly on actual water usages and patterns of buildings. Secondly, it was likely that the average reduction rate of residual chlorine in underground reservoirs were affected from the their capacities, because the average reduction rate of residual chlorine in underground reservoirs under $1,000m^3$ was 43 percent, on the other hand, that rate of underground reservoirs over $1,000m^3$ was 60 percent. Thirdly, through the field investigation, the retention time of drinking water in underground reservoirs were in the range from 0.3 day to 3.9 day. In addition to, the average reduction rate of residual chlorine were depended largely on the retention time of drinking water. When the retention time was under 24 hours, the average reduction rate of residual chlorine was 45 percent, and in case of over 24 hours, was 49 percent. Fourth, water level in underground reservoirs was averagely varied in the range from 0.1 m to 2.65 m at the height of underground reservoirs. If considered actual height of underground reservoirs, 37.6 percent of the height of underground reservoirs was only used. Consequently, the frequency of the inflow and outflow of drinking water in underground reservoir were very increased, and had an effect on the reduction of residual chlorine. Lastly, the investigations on hydraulic structure characteristics of underground reservoirs inside showed the locations of inflow and outflow of drinking water almost were in the opposite direction. And some buildings had several baffles in the middle. Nevertheless, their installations had no beneficial for the improvement of water quality.

• International Journal of Contents
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• v.14 no.3
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• pp.53-60
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• 2018

Based on the previous studies on sinkholes and ground subsidence conducted until date, the factors affecting the occurrence of sinkholes can be divided into natural environmental factors and human environmental factors in accordance with the purpose of the study. Furthermore, to be more specific, the human environment can be classified into the artificial type and the social type. In this study, the assessment indices for assessing risks of sinkholes and ground subsidence were developed by performing AHP analysis based on the results of the study by Lee et al. (2016), who selected the risk factors for the occurrence of sinkholes by performing Delphi analysis targeting relevant experts. Analysis showed that the artificial environmental factors were of significance in affecting the occurrence of sinkholes. Explicitly, the underground factors were found to be of importance in the natural environment, and among them, the level of underground water turned out to be an imperative influencing factor. In the artificial environment, the underground and subterranean structures exhibited similar importance, and in the underground structures, the excessive use of the underground space was found to be an important influencing factor. In the subterranean ones, the level of water leakage and the erosion of the water supply and sewage piping system were the influential factors, and in the surface, compaction failure was observed as an imperative factor. In the social environment, the regional development, and above all, the groundwater overuse were found to be important factors. In the managemental and institutional environment, the improper construction management proved to be the most important influencing factor.

• Journal of Environmental Health Sciences
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• v.26 no.4
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• pp.122-128
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• 2000

This study was carried out to survey trihalomethane formation potential(THMFP) levels in drinking underground water and to examine its characteristics in Kunsan area. In drinking underground water, THMFP increased with the lapse of reaction time and 96hr-THMFP was the highest of THMFPs examined. In many cases, 24hr-THMFP, 48hr-THMFP and 96hr-THMFP reflected 2hr-THMFP level due to the largest composition ratio of CHCl$_3$ decreased with the lapse of reaction of CHCl$_3$ among THM individuals. CHCl$_3$ was mostly formed within early 2hour of reaction time, but CHClBr$_2$ and CHBr$_3$ continued their formation until 48 hour. Accordingly, the composition ratio of CHCl$_3$ decreased with the lapse of reaction time while that of total Br derivatives increased. 96hr-THMFPs of drinking underground water in Kunsan area ranged from N.D.(not detected)~98.80 $\mu\textrm{g}$/$\ell$ and, in general, those of western section of Kunsan area, closer to the coast, showed the higher tendency. But, from their large range of variance, it could be considered that THMFPs differ individually even in the same section depending on such factors as the difference of water stream, circumstances of management and so on. All the parameters for water quality examined(pH, KMnO$_4$ consumption;UV$_{254}$ , TOC. Cl$^{[-10]}$ ) showed very week corelation with 96h-THMFP.

• Water for future
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• v.23 no.2
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• pp.239-250
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• 1990

The method for artificial grondwater recharge can be categorized into two groups, one is well method and the other one is scattering method. Underground piping method belongs to the latter group and it is to infiltrate water from porous pipes buried underground. This paper shows the result of indoor experiment and numerical analysis concerning this method. The purpose of the study is to maky the infiltration aspects and groundwater recharge in underground piping method. We have found that the recharge height is effect by the difference of water level and a distance of pipe laying.