• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.201-201
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• 2010

The evaporative desalination system with solar energy would be the efficient and attractive method to get fresh water. This study was described the development of Multi Effect Distillation(MED) with solar energy desalination system. The system was designed and manufactured Multi effect distillation on the capacity of $3m^3$/day. The experimental apparatus consists mainly of ejector pump, Hot water pump, flow meter, demister, cooler, evaporator and condenser. Evaporator and condenser were made Shell&Tube Heat Exchanger type with corrugated tube. The experimental variables were chosen $75^{\circ}C$ for hot water inlet temperature, 40, 60 and $80{\ell}$/min for hot water inlet volume flow rate, 6.0 and $8.0{\ell}$/min for evaporator feed seawater flow rate, $18^{\circ}C$ for sea water inlet temperature to cover the average sea water temperature and the salinity of sea water is measured about 33,000 PPM (parts per million). for a year in Korea. This study was analyzed the results of thermal performance of Multi Effect Distillation. The results are as follows, The experimental Multi effect distillation is required about 40 kW heat source for production of $3m^3$/day fresh water. Various operating flow rate was confirm in the experiments to get the optimum design data and the results showed that the optimum total flow was $8.0{\ell}$/min. Comparison of Single Effect Distillation with Multi Effect Distillation showed MED is at least more than double of SED.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.11
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• pp.2736-2744
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• 2013

In this paper, we present a Smart Water Treatment Plant using Zigbee USN devices and a real-time monitoring system in K-water Flow Meter Calibration Center Building. For verification, the data of vertical type WTP such as flow rate, pressure, water level and water temperature are obtained by the Zigbee USN devices, operating in 2.45 GHz band, and be wirelessly surveilled by the real-time monitoring system. The received data from the sensor is transmitted to the data processing device, and then the processed data can be monitored on a smart phone. Consequently, the pilot plant based on the low-cost and high-efficiency USN has been developed with the performance analysis for the communication network and remote monitoring system on mobile devices.

• Journal of Korea Water Resources Association
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• v.54 no.11
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• pp.903-913
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• 2021

In the flood season, the measurement of the river discharge has many restrictions due to reasons such as budget, manpower, safety, convenience in measurement and so on. In particular, when heavy rain events occur due to typhoons, etc., it is difficult to measure the amount of flood due to the above problems. In order to improve this problem, in this study, a method was developed that can measure the river discharge in a flood season simply and safely in a short time with minimal manpower by combining the functions of a drone and a surface velocity doppler radar. To overcome the mechanical limitations of drones caused by weather issues such as wind and rainfall derived from the measurement of the river discharge using the conventional drone, we developed a drone with P56 grade dustproof and waterproof performance, stable flight capability at a wind speed of up to 36 km/h, and a payload weight of up to 10 kg. Further, to eliminate vibration which is the most important constraint factor in the measurement with a surface velocity doppler radar, a damper plate was developed as a device that combines a drone and a surface velocity Doppler radar. The velocity meter DSVM (Dron and Surface Veloctity Meter using doppler radar) that combines the flight equipment with the velocity meter was produced. The error of ±3.5% occurred as a result of measuring the river discharge using DSVM at the point of Geumsan-gun (Hwangpunggyo) located at Bonghwang stream (the first tributary stream of the Geum River). In addition, when calculating the mean velocity from the measured surface velocity, the measurement was performed using ADCP simultaneously to improve accuracy, and the mean velocity conversion factor (0.92) was calculated by comparing the mean velocity. In this study, the discharge measured by combining a drone and a surface velocity meter was compared with the discharge measured using ADCP and floats, so that the application and utility of DSVM was confirmed.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.25 no.6
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• pp.529-537
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• 1992

Airlift pumps were tested to evaluate their pumping and aeration capacities. The pumps were 34.5 inch long made of 2, 3, 4 and 6 inch nominal diameter PVC pipes. An one hp air blower was used to supply the air. The air-flow rate was measured by an anemometer type air-flow meter and air pressure was level changes in a water tank from which water was pumped. Aeration by the pumps was tested by the standard aeration test method with the center of pump outlet positioned 3 inches above water surface. Oxygen concentrations in water were measured to determine aeration rate. As pumping head increased by water level draw-down in the tank water flow decreased while air flow increased. The reduction rate of water flow was higher with 4 and 6-inch pumps. Small pumps showed very minor changes in the reduction. Aeration rates were similar among 3, 4, and 6 inch pumps. With one hp air blower 6-inch pump at the minimum pumping head achieved the best performance in terms of water circulation.

• Analytical Science and Technology
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• v.21 no.3
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• pp.159-166
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• 2008

In this study, the characteristics of emulsified fuel and engine emissions were studied. Emulsified fuel which composed of water and diesel was manufactured by using homogenizer and ultrasonic generator. Engine emissions were studied whit engine dinamometer. In emulsified fuel, density and viscosity were increased with increasing water contents, but viscosity was decreased over 60% of water in emulsion fuel. The emulsion type of W/O changed to that of O/W over 60% of water in emulsion fuel. In the results of engine dinamometer test, NOx concentration and smoke density were reduced with increasing water contents in emulsified fuel but reciprocal in the case of THC, CO. Temperature and power were reduced with increasing water contents in emulsion fuel. In conclusion, it seemed that using emulsified fuel for diesel engine was effective for reducing NOx concentration and smoke density.

• Journal of the Korean Association of Geographic Information Studies
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• v.8 no.2
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• pp.157-165
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• 2005

The purpose of this study is to examine the relationship between land use patterns of riparian zones and water quality in the Geumho River watershed. A GIS database included digital land use maps (1:25,000), stream network extracted from digital topographic maps (1:5,000) and riparian zones maps by multi-buffering method. Pearson's correlation analysis was used to explain the relationship between the environmental conditions of a 30 meter buffer strip on each side and water quality. According to the result of investigation of riparian-level land use patterns, sub-watersheds on the lower Geumho River including Daegu metropolitan city were mainly developed as urban area such as residential, commercial and industrial ones, while sub-watersheds on the middle Geumho River and the main course of Nakdong River, agricultural ones such as a paddy, a dry field and an orchard. Meanwhile, the area-rate of riparian forests which play an important role in filtering nitrogen, phosphorus and sediment was estimated below the average 16%. The proportion of urban area in a 30 meter riparian bufferstrip had a negative correlation with water quality in each sub-watershed. But the proportion of forest area had a positive correlation with water quality. Henceforth, it is necessary to establish landscape planning for preparing and restoring the riparian buffer zones, concerning land form, soil type, the present land use pattern and economic aspects.

• Korean Journal of Food Science and Technology
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• v.30 no.3
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• pp.562-568
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• 1998

Rice (Dongjin-byeo) added with black rices (Chindo and Suwon-415) was cooked and the changes of texture and color of this cooked rice were investigated by texture analyser and color & color difference meter. The hydration time to come to the equilibrium condition was at least 11 hr in black rices. The optimum ratio of water to cooked rice added with black rice was 1.6 (ratio of water to rice) and the hardness of cooked rice added with 5% Chindo black rice was $5.66\;kg_f$. Regardless of ratio of water to rice, Hunter a value increased as the ratio of black rice addition to rice increased, while L value decreased. The color elution rate of Suwon 415 was 4 times greater than that of Chindo black rice. The pH of the steep water of Suwon 415 at $20^{\circ}C$ during 120 min decreased from pH 6.40 to pH 6.16 as the steeping time increased. The optimum heating time by microwave oven of cooked rice added with black rice was between $90{\sim}120\;sec$ to recover the original texture after cold storage treatment of 7 days.

• Journal of Environmental Science International
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• v.19 no.11
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• pp.1375-1384
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• 2010

Growth in population and urbanization has progressively increased the loading of pollutants from nonpoint sources as well as point sources. Especially in case of road regions such as city trunk road, national road and highway are rainfall and pollutants runoff intensive landuses since they are impervious and emit a lot of pollutants from vehicle activity. This research was conducted to investigate the nonpoint sources concentration and quantifying stormwater pollutants which are contained in rainfall runoff water. Three different monitoring sites in Jinju and Changwon city were equipped with an automatic rainfall gauge and flow meter for measuring rainfall and the volume of rainfall runoff. In the case of average EMC value, city trunk road was shown the highest value in target water quality items like as BOD, COD, SS, TN and TP. Or the amount of runoff loads by water quality items showed the highest value in city trunk road. And runoff load in city trunk road was 43.8 times high value compared to highway by value of city trunk road $356.7 mg/m^2$, highway $8.150 mg/m^2$, national road $19.99 mg/m^2$ in the case of BOD.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.24 no.2
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• pp.198-203
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• 2020

In this paper, we propose an artificial water level prediction system for small river flood prediction. River level prediction can be a measure to reduce flood damage. However, it is difficult to build a flood model in river because of the inherent nature of the river or rainfall that affects river flooding. In general, the downstream water level is affected by the water level at adjacent upstream. Therefore, in this study, we constructed an artificial intelligence model using Recurrent Neural Network(LSTM) that predicts the water level of downstream with the water level of two upstream points. The proposed artificial intelligence system designed a water level meter and built a server using Nodejs. The proposed neural network hardware system can predict the water level every 6 hours in the real river.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.419-419
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• 2021

수자원 관리 패러다임은 공급 위주에서 수요관리로 전환되고 있다. 가용한 수자원은 한정적이나 급속한 인구증가와 도시화로 인한 물 수요의 증가로 수요관리의 효율성이 중시되고 있기 때문이다. 기존 상수도시스템은 노후화로 가동효율이 점차 낮아지고 있으며, 인력으로 월 또는 격월로 소비자의 물 사용량을 검침해 실시간 관리가 불가능하여 수요와 공급의 불균형을 초래한다. 이러한 문제를 해결할 대안으로 IT 기술과 전통적인 물관리 기술을 접목한 Smart Water Grid는 양방향 통신장치를 이용해 실시간으로 소비자의 물 사용량을 모니터링한다. 물 사용 특성을 잘 파악하면 보다 정확한 물 수요 예측이 가능하다. 특히 소비자들의 시간별, 평일, 주말, 그리고 주별 물 사용 특성을 파악하면 미래 물 수요 예측에 도움이 된다. 예측된 물 수요량에 따라 물 공급 배분 계획을 수립하여 운영 효율성을 높일 수 있다. 물 수요예측 방법 중 k-mean 군집분석은 시간별 물 사용량을 이용해 서로 유사한 여러 개의 부분집합으로 할당하여 분류하는 Machine learing 방법으로 물 사용의 유사성을 파악할 수 있다. SWG 연구단은 2019년 Vietnam Hai Duong province에 SWG Pilot plant를 구축하고 27개의 Smart water meter를 설치하여 운영하고 있다. 이에 본 연구에서는 소비자의 물 사용 특성을 분석하기 위해 27개 SWM로부터 수신된 2019년 11월 14일부터 2020년 12월 3일까지 1시간 단위의 물 사용량 데이터를 수집하였다. 그리고 k-mean 군집 방법을 이용해 시간별, 평일, 주말, 그리고 주별 물 사용 특성을 분석하였다. 이 때 최적의 군집 개수 결정을 위해 Elbow 방법을 적용하였다. 분석 결과 각 소비자의 물 사용량 특성에 따라 평균 물 수요패턴 추정이 가능하며, 향후 물 수요 예측에 도움이 될 것으로 사료된다.