• Journal of Korean Society on Water Environment
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• v.34 no.2
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• pp.226-233
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• 2018

Small-scale wastewater discharge facilities account for 98% of all workplaces, but in the generation and emission of major pollutants, they account for 27.5 % and 23.5 %, respectively. Since the proportion of the emission load of the small-scale workplace is not large, the national environmental policy has been established mainly around large-scale wastewater discharge facilities. However, in the case of specific hazardous substances in water, the amount of the discharge load of the small-scale wastewater discharge facility was 2.4 times higher than that of the generation load. Certain types of specific hazardous substances in water, which have a higher discharge load than large-scale wastewater discharge facilities, account for 24 ~ 32 %. There are also cases in which the discharge load from a small-scale discharge facility is more than four times higher, depending on the specific kind of water pollutant. As a result of inspections, the violation rate of the small-scale wastewater discharge facility among the total violations by facilities is 93.9 ~ 97.5 %. As a result, the ecotoxicity value of small-scale wastewater discharge facilities was high in most industries, and there was a fluctuation in the measured value. This indicates that the ecological integrity of the water system can be largely influenced by small-scale wastewater discharge facilities. Therefore, it is necessary to expand the environmental management of small-scale wastewater discharge facilities, and in some cases, the effect of the improvement in quality may be more significant than in the management of large-scale wastewater discharge facilities.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.4
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• pp.415-421
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• 2004

The voltage profile of Zinc/Air battery during discharge has very flat pattern in a given voltage range, But, if not enough the porosity in cathode, as a result of that capacity, energy and discharge voltage of batteries become low. Therefore, we focused the pore effects in activated carbon for cathode. We examined discharge voltage, specific capacity, specific energy, resistance and characteristics during the GSM pulse discharge upon different kinds of activated carbon in Zinc/Air battery, Also we measured porosity of the air cathode according to the ASTM. So we achieved improvement of specific capacity, specific energy and discharge voltage according to increase meso pores of activated carbon. We found the optimized activated carbon material for Zinc/Air battery.

• Korean Journal of Agricultural Science
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• v.38 no.2
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• pp.309-314
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• 2011

The purpose of this study is to select the dominant discharge which mostly affects the formation of the channel shape in Yo-Stream. So far, three different discharge conditions such as bankfull discharge, discharge of a specific recurrence interval, and effective discharge have been considered as an indicator of dominant discharge. Therefore, three different discharge conditions were studied and based on the study results, dominant discharge was selected for Yo-Stream. When comparing bankfull discharge and effective discharge at Beonam stream gaging station, it has turned out that effective discharge was 10 $m^3$/sec, which is 6 times greater than bankfull discharge of 58.83 $m^3$/sec. Furthermore, when comparing bankfull discharge and discharge of a specific recurrence interval, bankfull discharge was quite similar to discharge with recurrence interval of 1.52 years. Previous study results also indicate that dominant discharge occurs with recurrence interval of similar duration. Therefore, discharge of 58.83 $m^3$/sec was considered as a dominant discharge, which corresponds to discharge with recurrence interval of 1.52 years.

• Journal of the Korean Geographical Society
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• v.40 no.3 s.108
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• pp.274-284
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• 2005

On the subject of Yeoungsan River Yeoungbon c and Seumjin River Seumbon e site discussing as the measuring points of discharge and Quality by the Department of Environment, this study executes the tests of proprieties and examines the methods of flow measuring and assessment. The result of this study may summarize as belows. According to the hydrogeomorphological aspects and artificial effects, Yeoungbon c and Seumbon e site are not proper for the measuring points of the water levels. Also, the methods of river discharge measuring by the specific discharge method, first tried in this study, has an enough reliability which can be used to measure the site where is difficult to measure the flow directly or to select the representative site to measure on the up and downstream. In case of accumulating the specific discharge data throughout the flow observation by seasons and periods for a long time, these may be used to measure the flow as well.

• Nuclear Engineering and Technology
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• v.54 no.3
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• pp.1003-1015
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• 2022

The new methodologies to derive discharge limits considering operational flexibility according to international safety standards were developed to help reduce the environmental releases of radioactive effluents from nuclear power plants (NPPs). To overcome the limitations of the two existing methods to set up discharge limits assuming a specific statistical distribution of the effluent discharge, two modified equations were newly proposed to directly derive a particular discharge limits corresponding to the target 'compliance probability' based on the actual annual discharge data for a specific NPP and radionuclide groups. By applying these to the actual yearly discharge data of 14 Korean NPPs for 7 radionuclide groups for the past 20 years, the applicability of two new methodologies to actual cases was demonstrated. The 'characteristic value' with approximately a 90% compliance probability for each Korean NPP and radionuclide group was proposed based on the results. The new approaches for setting up the discharge limits and the characteristic values developed in this study are expected to be effectively utilized to foster operator's efforts to progressively reduce the environmental releases of radioactive effluents of NPPs relative to the previous discharge data considering operational flexibilities.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2006.04a
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• pp.68-71
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• 2006

Seasonal fluctuation of groundwater level by pumping amount and stream discharge at the riverbank filtrate site adjacent to the Nakdong River in Daesan-Myeon was characterized. Groundwater level fluctuation shows increase in wet season (June, July, August and September) and decrease in dry season (the other months). Seasonal variation of pumping amount shows similar trend to the groundwater fluctuation due to higher consumption of potable water in summer. The relation of specific capacity, Nakdong River and pumping quantity was analyzed. The logarithmic relationship between specific capacity and the stream discharge gives high correlation coefficient, 0.96. This fact indicates that the increase of stream discharge rate reduces the rate of drawdown in the pumping area in wet season.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1997.11a
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• pp.144-148
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• 1997

We synthesized polyaniline films electrochemically under constant current conditions, which exhibited electric conductivity as high as 100 S/cm. By charge and discharge cycling of polyaniline films, we obtained specific discharge capacity as high as 195 mAH/g using HSO$_4$- doped polyaniline. For the polyaniline synthesized using H$_2$SO$_4$ and HClO$_4$ composite electrolyte. we also obtained specific discharge capacity as high as 134 mAHg which rivals inorganic electro- active materials.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1999.10c
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• pp.753-758
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• 1999

Concentration and discharge have been intensively monitored at the drainage canal in a paddy field area during storm-periods. Among 4 storm runoffs, the No. 2 and No. 3 runoff was in the fertilizer application period. The specific load-specific discharge equation L=aQ\ulcorner have different characteristics for the pollutants. The coefficient of b generally shows values of more than 1 for T-N, about 1 for COD\ulcorner, and less than 1 for T-P. For same specific discharge, No. 2 runoff shows higher specific load than other runoffs. For the coefficient of determination of the L-Q equation, COD\ulcorner is higher than T-N and T-P. The mean concentration of direct runoff, significantly depending on the storm events, is 0.6 to 8.3mg/ιfor T-N, 0.05 to 0.51 mg/ι for T-P, and 10.0 to 18.3 mg/ι for COD\ulcorner.

• Journal of Korean Society for Atmospheric Environment
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• v.31 no.6
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• pp.530-537
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• 2015

The wet electrostatic precipitator (wet ESP) is an effective control device which removes submicron particles reentrained in a collection plate and water soluble gas. However, its collection efficiency decreases, as its operation is subject to water-induced distortion of the collection electrode. In order to make up for the limitation, we modified the wet ESP system by installing electrosprayed discharge electrodes. The modified wet ESP system can wash both the collection plate and discharge electrode. As a result, we were able to fabricate a compact wet ESP with a small specific collecting area ($0.18m^2(m^3/min)$) that can accomplish a high collection efficiency of fine particles (97.1%). In addition, the device obtained a relatively low specific corona power of approximately $10W/(m^3/min)$.

• Journal of Korean Society on Water Environment
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• v.24 no.4
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• pp.452-457
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• 2008

Nonpoint source (NPS) pollution is caused by rainfall moving over and through the ground. As the runoff moves, it picks up and carries away various pollutants from NPS. The discharge pattern of NPS pollutant loads is affected by the distribution of the rainfall during the year. This study analysed relationship between the rainfall event and the stream flow rate, and estimated the rainfall discharge ratio on the specific design flow which can be used as nonpoint discharge coefficient for the estimation of NPS pollution load. It is considered that nonpoint discharge coefficient can be effectively used for the calculation of NPS pollution load at the time of water quality modelling for the management of Total maximum daily load (TMDL).