• The Journal of Engineering Geology
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• v.20 no.1
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• pp.79-87
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• 2010

Field water qualities (temperature, pH, Eh, EC, DO) was monitored by 6 times March to September 2009 on background water (BW) and acid mine drainage (AMD0, AMD1, AMD2 and AMD3 points), and flow rate was measured on AMD0 point. Acid mine drainage flowed out from abandoned Ilgwang mine were high acid waters that lower than pH 3, and Eh component was ranged 400 to 600 mV. EC measured on acid mine drainage were higher over 10 times than background water, DO component was increased by reaction on the air during the water flow from AMD0 point to AMD4 point. Heavy metal concentrations in acid mine drainage were ordered Fe > Cu > Zn > Mn > As > Cd, and Fe concentration was highest for 81.870~474.30 mg/L. Monitoring periods measured maximum concentrations of heavy metals were May for As and Cd, June for Fe, July for Cu, Zn and Mn. The periods measured minimum concentrations were monitored April for Cd and Mn, September for Fe, Cu, Zn and As. Discharge mass of heavy metal components were calculated 53.44 kg for Fe, 6.25 kg for Cu, 5.26 kg for Zn, 2.13 kg for Mn, 0.14 kg for As and 0.04 kg for Cd, respectively. Total discharge mass of heavy metal components were calculated 67.26 kg for 1 day, and Fe component was taken 79% of total mass.

• Journal of Korean Society on Water Environment
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• v.26 no.5
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• pp.761-767
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• 2010

This study introduces a model of territorial analysis on Chungcheongnam-do Nonsan-chun valley area, which gives an example of a method of selecting the management area for non-point pollution source from land use to help eliminate its source. High discharge load per unit area signify high level of land ratio with high level of basic unit of development load (including factory sites, school sites, roadways), which mean that there are a significant level of urbanization. It is these areas with the examination of the water quality of the nearby river that should be considered as the management area for non-point pollution source. Thus, the management area for non-point pollution source should be sought in areas with high discharge load per unit area and high density of water pollution area. When level of drainage is high the pollution density level is relatively lower, and when the level of drainage is low the density level is relatively higher. The level of pollution from non-point pollution source is much lower with more water flowing through. The possible non-point pollution source areas that were selected with these standards were then examined with the distance from the river, the slope angle, land usage, elevation, BOD discharge density load, T-N discharge density load, T-P discharge density load, and were given a level one through five. Out of the possible areas Nonsan-si Yeonmu-eup Anshim-li was the densest area, and it was given level one. The level one area should be examined further with the field analysis to be selected as the actual management area for non-point pollution source.

• Journal of the Korean GEO-environmental Society
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• v.12 no.12
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• pp.37-46
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• 2011

An application frequency of vertical drainage method is increasing as an effective consolidation acceleration method. PBD method is most frequently used as a consolidation acceleration method in vertical drainage methods. PBD is economical and easy to operate but has some problems those are an environmental pollution and a decrease of a discharge capacity caused by bending of drainage materials when it is used in great depth. SCP method was frequently used because it's discharge capacity was good but now it is rarely used because of an increase of the material price because of an order imbalance. As the way to solve these problems, GCP method has been to the fore. For analyzing the effect of GCP method on the discharge capacity, three types of composite discharge capacity tests are done by using GCP, SCP and PBD respectively with the circle case, ${\phi}38{\times}h70cm$. On the contrary to this, GCP shows the worst discharge capacity for a decrease of the void ratio and the clogging phenomenon caused by increasing load. Also to figure out the clogging range of GCP, the clogging of GCP is checked in each load stage with a large case($1.0m{\times}0.5m{\times}1.1m$) which has clear acrylic front face. The diameter of GCP was 35cm and a clogging phenomenon occurred in 10% approximately. The result shows that the discharge capacity of GCP was given the lowest value for a decrease of the void ratio and the clogging phenomenon causing by increasing load. And the clogging phenomenon mostly occurred within 10% of GCP's diameter range.

• Journal of the Korean Geosynthetics Society
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• v.13 no.2
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• pp.11-20
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• 2014

To create a large-scale complex, it is often the case to perform ground improvement by using vertical drain method after the reclamation of coastal soft ground, for construction period shortening and stable site renovation. During this process, the pore water migrates to the horizontal drainage layer of the ground surface through the vertical drain installed in the soft ground and discharged out to the open. In the past sand was used as the material for the horizontal drainage layer in numerous cases, however recently, due to material shortage and high pricing, the use of crushed stones has increased. To prevent mixing of the materials between the horizontal drainage layer and the upper landfill, geosynthetics (PPMat) are installed. However, the use of geosynthetics results in high additional cost for material purchase and installation, therefore it is necessary to examine the validity of the installation itself. In this study, to verify the necessity, model tests were performed. Results from the model tests indicate that the drainage ability of the horizontal drainage layer is barely affected by the application of geosynthetics.

• Journal of Korean Society of Forest Science
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• v.100 no.1
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• pp.25-33
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• 2011

The purpose of this study is to develop a standard calculation program of forest road drainage facilities that may help forest road designers to design forest road drainage facilities more conveniently and precisely. Especially, the characteristics of this program is that the forest road designers may calculate the amount of outflow in the basin using rainfall intensity data conveniently, without the data designers should acquire through site measurements when they carry out indoor preliminary measurements before they go out for outdoor measurements. In this manner, excessive design may be restrained by offering minimum standard calculation for drainage structures. And also this study was designed to facilitate proper layout of drainage structures by calculating outflow discharge of each basin where forest roads will be installed. Especially, this study will contribute to leveling-up of forest design techniques as the researcher has prepared the reports on whole process of drain pipe installation and provided them in the form of computer file or printout, which show a rational design process, and make it possible to modify in case of an error.

• Journal of Hydrogen and New Energy
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• v.25 no.5
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• pp.516-524
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• 2014

Proper discharge of nitrogen gas and water condensate is required in a conventional fuel cell system for performance, stability and durability of fuel cell stacks. Present study covers the development of integrated unit and its functioning logic for simultaneous nitrogen gas purge and water condensate drainage in a fuel cell vehicle system. Configuration of condensate drainage pipe, purge valve and level sensor is considered and optimized in physical integration. As a key factor, discharge time is considered and optimized based on the test result of constant-current operation with various operating temperature in logic development. Consequently, derived optimal values are applied and verified in actual vehicle drive mode test. Increase of system design flexibility, weight reduction and cost reduction are anticipated with this study. Additional study for physical and logical improvement is currently being implemented.

• KCID journal
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• v.13 no.2
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• pp.283-292
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• 2006

The characteristics of nonpoint source pollutant loads in upstream of Nakdong River were studied through analysis of pollutant loads of 10 sub-watersheds divided based on administrative district. The discharge and pollutant concentration of each sub-watershed were collected from Nakdong-River Water Research Institute and Daegu Regional Environmental office, respectively. Pollution items analysed in this study were BOD, T-N and T-P. The delivery loads of the nonpoint source pollutions of each sub-watershed were calculated after analysing the concentration of the pollution of each site. Several points were found from the results. Firstly, in general, city areas including Sangju, Andong showed higher degree of nonpoint pollution than country areas including Cheongsong, Yeongyang. The sub-watersheds located upstream side, such as Yeongju, Bonghwa, Necessarily show better water quality than the sub-watersheds located downstream side, such as Mungyeong, Uiseong. This result indicates that a given pollution condition within the watershed can be more sensitive than location factor to the level of water quality. Secondly, the delivery load and area of watershed were not necessarily correlated in the sense of water quality, while the discharge was shown to be highly correlated to the delively load of pollution. Lastly, sewage and waste caused from population and livestock, as well as landuse factor, were found to significantly contribute to the water pollution. Alternative solutions for controlling pollution source, therefore, should be provided to meet target levels of water quality in these regions.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2005.10a
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• pp.313-317
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• 2005

This study aimed to estimate applicability of a model to simulate circulation in estuarine lake caused by operation of drainage gates. The model consists of 2D (depth-averaged) hydrodynamic models, Delft3D-FLOW model and operation model for drainage gates. The flow through drainage gates was calculated using weir formulae with discharge coefficient, 0.8. The simulations are performed under two conditions: uncontrolled condition and controlled by periods of two days. The results on simulation of the model showed that the water level in estuarine lake was tend to increase above mean sea level. Therefore it was proved that the calibration and verification were needed in order to applicate this model for Saemankeum area.

• Proceedings of the Korea Water Resources Association Conference
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• 1993.07a
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• pp.227-240
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• 1993

• Korean Journal of Hydrosciences
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• v.5
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• pp.99-114
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• 1994

Three purposes of this study are as follows : The first was the development of the extension method for the limited data observed in an urban drainage basin. The second was the analysis of the correlation between storm water runoff and NPS(non-point source) Pollutant discharge. The last was the calculation of the monthly and annual specific NPS loads using the established correlation. The selected model was the SWMM(Storm Water Management Model) developed by the US EPA(Environmental Protection Agency). As a result of this study, the best correlation between storm water runoff and NPS pollutants discharge was produced by the nonlinear correlation between runoff rate(mm/hr) and specific loads rate(kg/ha) for all pollutants studied : SS, COD, BOD, and TN. The best correlation through the analysis based on evently total mass was made by the linear correlation between the by the nonlinear correlation for CASE2. The NPS annual specific loads for the urban basin studed were 4,993 kg/ha/year for SS, 775 kg/ha/year for BOD, 3,094 kg/ha/year for COD, 257 kg/ha/year for TN, respectively. And the proportion of the NPS annual specific loads to the total annual specific loads were 41 % for SS, 13 % for BOD, 29 % for COD, and 21 % for TN.