• Proceedings of the Korea Water Resources Association Conference
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• 1996.05a
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• pp.597-602
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• 1996

• Proceedings of the Korea Water Resources Association Conference
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• 1987.07a
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• pp.139-145
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• 1987

• Magazine of the Korean Society of Agricultural Engineers
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• v.32 no.3
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• pp.56-66
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• 1990

To investigate the status of irrigation water use and the degree of repeated use of irrigation water, observations for water balance analysis were made during the irrigation periods in 1986 and 1987 crop year. The total area of studied site is 1,441 ha. The site is a major portion of Jedaecheon basin which is located in Bubuk-myeon, Miryang-gun, Gyeongnam Province. The studied area was subdivided into six small blocks. The water balance analysis for these subdivided blocks were carried out considering characteristics of each block. Obtained results are as follow: 1.In mountainous sloppy paddy area(less than 7% slope), the surface inflow was 5A mm/day in average that is one third of the surface inflow into plain paddy area ; 16.7 mm/day. 2.The surface inflows at the vegetative stage and the ripening stage were 15.5 mm/day and 10.4 mm/day, respectively. Those figures were larger than the actual consumptive use at respective same stages ; 13.3 mm/day and 9.2 mm/day, respectively. Whereas, the surface inflow at generative stage was 12.5 mm/day which was less than 14.0 mm/day ; the actual consumptive use. 3.The range of the variation of water storage term was 1 mm/day. This means that there were no change in depth of ponded water on paddy fields. The relationship between the variation of water storage(AS) and the variation of ground water table(H) could be expressed as follow: : AS=0.14H+0.26 4.The ground water inflow: into the transition region ; paddy fields which are located continuously from the mountainous area to the plain area, was larger than the out flow from this region, in general. Rowever, in the plain region where the ground water utilization was predominant, the ground water outflow from this region was larger than inflow: to this region. The relationship between the ground water flow(G2- G1) and the consumptive use in large paddy area(D1-D2) could be expressed as follow: (G2-G1) =0.95(D1-D2) -3.79

• Water for future
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• v.26 no.4
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• pp.47-60
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• 1993

The evaluation of grounwater flow in the Ingulam valley catchment area in the vicinity of SamKwang mine was studied. In this study, field hydraulic tests, groundwater flow measurement, and MODFLOW model application were carried out. The results of analysis are described as follows. The rainrate infiltrated into the ground in the study area, hardly reached the gneiss region deeper than EL.(+)100m above the surface of seawater. The rainwater infiltrated into the ground near the water system boundary, flowed out into the vicinity of streams and the travel time was between 15 and 263 years. Also, the estimated total flow rate of the groundwater in the study area was 307㎥/day.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.3371-3376
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• 2007

The design of a ground-source heat pump system includes specifications for a ground loop heat exchanger where the heat transfer rate depends on the thermal conductivity of the ground. To evaluate this heat transfer property, in-situ thermal response tests on four vertical test boreholes with different grouting materials were conducted by adding a monitored amount of heat to water over various test lengths. By measuring the water temperatures entering and exiting the loop, water flow rate, and heat load, effective thermal conductivity values of the ground were determined. The effect of increasing thermal conductivity of grouting materials from 0.82 to 1.05 W/m$^{\circ}C$ resulted in overall increases in effective ground thermal conductivity by 25.8% to 69.5%.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.21 no.8
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• pp.468-474
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• 2009

Ground water source heat pump system is the oldest one of the ground source heat pump systems. Despite of this, little formal design information has been available until recently. The important design parameters for open system are the identification of optimum ground water flow, heat exchanger selection and well pump. In this study, the capacity of 50 RT system of two well type ground water heat pump system was used. As a result, static water level was -7 m and the level during the heating operation was -32 m, cooling operation was -40 m. The initial static water level recovered within 48 hrs. The temperature of ground water is $15.6^{\circ}C$ for heating season and $16.2^{\circ}C$ for cooling season and does not depend on the outdoor temperature. Operation efficiency of the system shows that, COP 3.1 for heating and COP 4.2 for cooling.

• Water for future
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• v.12 no.1
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• pp.21-27
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• 1979

Ground water stored in the alluvium and the rocks provides the vase flow of the streams and can be withdraw from wells and infiltration galleries. And it is also recharge naturallyby precipitation. The amount of ground water in the four major basins it is estimated to be about 137,000 million cubiv meters(Table1), while nationwide ground water storage to be about 232,000 million cubic meters. The estimation of storage volume has been made on the basis of assumed thickness of the saturated zone of the different rocks and assumed porosities of those rocks. The values of the porosity of alluvium and saprolite were assumed to be 25% and 40% respectivvely which are based on tests made of similar materials in Georgia, U.S. The volume of water in storage is believed to be a conservative estimate. Detailed geologic and hydrologic investigation should be made where and when water resources are needed.

• Journal of the Korean Geotechnical Society
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• v.26 no.5
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• pp.37-48
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• 2010

In this study, the seepage flow monitoring method by the hydraulic head loss rate was developed for the purpose of application to offshore construction site enclosed by cofferdams in which seepage force varies periodically. The amount of the hydraulic head loss rate newly defined in this graph was in a range between 0 and 1. The zero of the rate means the existence of flow with no seepage resistance. The 1 of the rate means no seepage flow through the ground. The closer to 1 the coefficient of determinant in the hydraulic head loss graph is, the more the ground through which seepage water flows is stable. The closer to 0 the coefficient of determinant in the hydraulic head loss graph is, the more the ground through which seepage water flows was unstable and the higher the possibilities of existence of empty space or of occurrence of piping on the seepage flow pass in the ground is. The hydraulic head loss graph makes it possible to monitor sensitively the situation of seepage flow state, and the graph helps to understand easily the seepage flow state at the specific section on the whole cofferdam.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.58 no.4
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• pp.455-460
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• 2009

A number of factors combine to make ultraviolet radiation a superior means of water purification for ground water, rainwater harvesting systems and so on. Ultraviolet radiation is capable of destroying all types of bacteria. Additionally, ultraviolet radiation disinfects rapidly without the use of heat or chemical additives which may undesirably alter the composition of water. In a typical operation, water enters the inlet of a UV lamp and flows through the annular space between the quartz sleeve and the outside chamber wall. The irradiated water leaves through the outlet nozzle. Several design features are combined to determine the dosage delivered. The first is Wavelength output of the lamp, the Second is Length of the lamp - when the lamp is mounted parallel to the direction of water flow, the exposure time is proportional to the length of the lamp, the third is Design water flow rate - exposure time is inversely related to the linear flow rate, the forth is Diameter of the purification chamber - since the water itself absorbs UV energy, the delivered dosage diminishes logarithmically with the distance from the lamp. In this paper, It describe the how to design optimal UV disinfection device for ground water and rainwater. To search the optimal design method, it was performed computer simulation with 3D-CFD discrete ordinates model and manufactured prototype. Using proposed design method manufactured prototype applied to disinfection test and proved satisfied performance.

• Journal of Soil and Groundwater Environment
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• v.6 no.3
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• pp.107-117
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• 2001

The characteristics of groundwater movement under the heavy rainfall at Nan-ji waste landfill site are studied using HELP(Hydraulic Evaluation of Landfill Performance) program, which calculates the daily leachate in the Nan-ji waste landfill site. In this study, instead of the average recharge value, which is used in the past study, the real reacharge value is used to calculate the daily leachater. It is found about 70 times greater than thor average recharge value under the condition of heavy rainfall in the rainy season. The flow characteristics of groundwater for water level fluctuation is simulated using the ground water flow model MODFLOW(A Modular 3-D Finite Different Groundwater Flow Model) program, and the slurry layer is newly added. The result of the study is different from that of the ordinary simulation, which shows much higher ground water level than from the ordinary simulation.