• 조명전기설비학회논문지
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• 제18권2호
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• pp.44-48
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• 2004

수표면을 전극으로 사용한 무성방전형 오존발생기를 제안하고 수중의 전도도 변화가 수표면 방전에 미치는 영향을 실험적으로 조사하였다. 수표면 방전에 중요한 영향을 줄 수 있는 요소로 방전공간내의 이온과 수중의 이온 및 극성분자등이 있다. 본 연구에서는 전도도를 변화시켜 수중에 존재하는 이온의 수를 조절함으로써 방전특성을 변화시키고자 하였다. 이를 위해 증류수내에 각각 다른양의 NaCl을 투입함으로써 전도도를 변화시켰고 이때의 전류-전압특성과 오존발생특성을 비교 조사하였다. 결과적으로 순수한 증류수를 사용한 경우보다 NaCl을 투입한 경우 안정된 방전을 발생시킬 수 있었고 투입하는 NaCl의 양을 늘여감에 따라 방전개시전압을 낮출 수 있었다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
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• pp.728-733
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• 2002

The measurement of river discharge is among the most fundamental observations and is necessary for understanding many water-related issues, such as flooding hazards, sediment transportation, and nutrient movement. Traditionally river discharge is estimated by measuring the water stage and converting the measurement to discharge using a stage-discharge rating curve. The possibility of monitoring river discharge from satellites has been largely ignored, because it is difficult to measure water surface information from space with sufficient precision. In this paper, an efficient approach to discharge estimation using mainly satellite data is developed and described. The proposed method, which focuses on the measurement of water-surface width coupled with river width-stage and stage-discharge relationships, is applied to the Yangtze River with good results.

• 한국물환경학회지
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• 제34권2호
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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.

• 식품보건융합연구
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• 제5권6호
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• pp.5-9
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• 2019

Desalination requires large energy. This experiment deals to desalinate brackish water through solar panels. The discharge from desalination plants is almost entirely water, and .01 percent is salt. Desalination is a process that extracts minerals from saline water. Solar-powered desalination technologies can be used to treat non-traditional water sources to increase water supplies in rural, arid areas. Water scarceness is a rising dilemma for large regions of the world. Access to safe, fresh and pure clean drinking water is one of the most important and prime troubles in different parts of the world. Among many of water cleansing technologies solar desalination/distillation/purification is one of the most sustainable and striking method engaged to congregate the supply of clean and pure drinkable water in remote areas at a very sound cost. Six types of dripper having discharge 3 - 8 lh-1 were installed one by one and measured discharge and volume of clean water indicated that at 6 lh-1 untreated water discharge have maximum evaporation and volume of clean water was 19.2 lh-1 at same temperature and radiations. Now strategy was developed that when increased the temperature the intake discharge of untreated water must be increased and salt drained water two times more than treated water.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2008년도 춘계학술대회 논문집
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• pp.266-269
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• 2008

In this study, the results of experimental investigation on the water discharge capability of sluice caisson for tidal power plant were presented. In particular, the focus of the study was placed on the examination of change in water discharge capability of a sluice caisson according to the installation of rubble mound. For this purpose, a hydraulic experiment was carried out in an open channel flume with a great care to the measurement of discharge and water level in the flume since they greatly affects the estimation of the discharge capability of each sluice caisson. In the analysis, the experimental data of four different sluice models were used, which showed that the installation of rubble mound affects in different manner depending on each sluice caisson model. When each of the four sluice models were placed on the rubble mound respectively, the water discharge increased for one sluice caisson, whereas decreased for other three sluice caissons. Further detailed analysis is needed to quantitatively estimate the influence of installation of rubble mound on the water discharge capability of a sluice caisson.

• 전기학회논문지
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• 제58권4호
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• pp.783-787
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• 2009

A point-to-mesh type discharge system, utilizing a water-pen point as a corona discharge electrode and a mesh as an ion induction electrode, has been proposed, and the effect of the water-pen point electrode of the discharge system to the ionic wind velocity and generation yield was investigated. It was observed that the proposed discharge system with the water-pen point electrode can generate a higher ionic wind velocity as compared with that of the metal point electrode. As a result, the peak ionic wind velocities of 2.61 and 4.05 m/s for the positive and negative corona discharges of the proposed discharge system can be obtained, which are 1.39 and 1.15 times higher than those of the metal point electrode with same design. The ionic wind generation yield of 4.72 m/s/W of the discharge system with the water-pen point electrode was obtained for the positive corona, which was 3.66 times higher than that of the metal point electrode. This enhancement may be due to the effect of the water-pen point electrode.

• 한국물환경학회지
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• 제24권4호
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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).

• 한국농공학회:학술대회논문집
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• 한국농공학회 2005년도 학술발표논문집
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• pp.56-60
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• 2005

It is necessary to irrigate for agriculture in Korea and agricultural canals play important roles in irrigation. Nowadays gauging water discharge in canals is important because of water shortage in Korea. But It is rare to gauging water discharge in canals. Several water level gauges are installed in agricultural canals through TM/TC. But the abilities of the gauges are insufficient for agricultural water metering. In this situation, we are developing the water discharge metering system which is inexpensive and easy to maintain.

• Environmental Engineering Research
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• 제10권3호
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• pp.144-154
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• 2005

The use of ozone gained acceptance in the production of ultrapure water because of its powerful oxidizing ability. Ozone is currently used to deactivate microorganisms and remove organic contaminants. However, interest also exists in using radical species, which arc stronger oxidants than ozone, in such processes. One means of producing radical species is by corona discharge. This work investigates the use of a novel pulseless corona-discharge system for the removal of organic substances in ultrapure water production. The method combines corona discharge with electrohydrodynamic spraying of oxygen, forming microbubbles. Experimental results show that pulseless corona discharge effectively removes organics, such as phenol and methylene blue, in deionized water. The corona-discharge method is demonstrated to be comparable to the direct use of ozone at a high-applied voltage. The results also show that a minimum applied voltage exists for operation of the corona-discharge method. In this work, the minimum applied voltage is approximately 4.5 kV. The kinetic rate or phenol degradation in the reactor is modeled. Modeling results show that the dominant species of the pulseless corona-discharge reactor are hydroxyl radical and aqueous electron. Several radical species produced in the pulseless corona-discharge process are identified experimentally. The. major species are hydroxyl radical, atomic hydrogen species, and ozone.

• 상하수도학회지
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• 제27권5호
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• pp.581-590
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• 2013

A research was performed for zero discharge system of waste water which is produced from energy recovery process of waste and biomass. Leachate and all kinds of waste water should be separated and integrated into three categories in addition to converting existing leachate treatment facility into waste water treatment facility as well as introducing a management system of reverse osmosis membrane facility and bioreactor landfill. Following these conditions to better water treatment process, it was likely to produce over 3,000 tons of low-grade recycling water and 2,000 tons of high-grade recycling water per day when zero discharge system of waste water is applied starting from 2016. Economical efficiency was also surveyed in total treatment fee. Present system costs 18,129 million won per year, and suggested zero discharge system would cost 15,789 million won per year.