• 한국농공학회지
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• 제30권3호
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• pp.114-120
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• 1988

A water surface profile computation model using a standard step procedure was developed for gradually varied flow at an irrigation channel network. Flow characteristics ab Banweol district near Suweon were field monitored during irrigation periol of 1987. The model was applied to the main system at the district and the simulation results were compared to the field data. The results are sumrnarized as follows ; 1. The simulated water surface profiles from the model were in good agreement with the measured water surface profiles at different flow rates. 2. The model applicability for defining a stage-discharge relationship at a channel reach was demonstrated with reasonable accuracy when water stage and friction factor were given. 3. The roughness coefficient was found to be a major factor sigrificantly affecting computed water surface profile among a few physical input parameters for the model.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2003년도 학술발표논문집
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• pp.295-298
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• 2003

In this study, It classified type of irrigation water development in islands district. As result, the types which were type of reservior, fleshwater lake, pumped storage, ets. Most of islands district has developed reuse irrigation system as a pumped storage system. But, Irrigation water-reuse ratio doesn't define a basis clearly and the value of measurement for water-reuse ratio doesn't exist so far. so, we measured Irrigation water-reuse to clarify for water-reuse ratio in a pumped storage system.

• 설비공학논문집
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• 제27권4호
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• pp.179-186
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• 2015

In this study, the actual energy consumption of the secondary side District Heating System (DHS) with different hot water supply temperature control methods is compared. The two methods are Outdoor Temperature Reset Control and Outdoor Temperature Predictive Control. While Outdoor Temperature Reset Control has been widely used for energy savings of the secondary side system, the results show that the Outdoor Temperature Predictive Control method saves more energy. In general, the Outdoor Temperature Predictive Control method lowers the supply temperature of hot water, and it reduces standby losses and increases the overall heat transfer value of heated spaces due to more flow into the space. During actual energy consumption monitoring, the Outdoor Temperature predictive Control method saves about 6.6% of energy when compared to the Outdoor Temperature Reset Control method. Also, it is found that at partial load condition, such as during daytime, the fluctuation of hot water supply temperature with Outdoor Temperature Reset Control is more severe than that with Outdoor Temperature Predictive Control. Thus, it proves that Outdoor Temperature Predictive Control is more stable even at partial load conditions.

• Corrosion Science and Technology
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• 제18권2호
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• pp.55-60
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• 2019

Corrosion failure in the convection part of peak load boiler (PLB) of the district heating system led to water leakage. Herein, Internal Rotary Inspection System (IRIS) inspection was employed to examine wall thinning and the cause of leakage in the flue tube. The corrosive products of the turbulator and tube were investigated using scanning electron microscope combined with energy dispersive spectroscopy, X-ray diffraction, and inductively coupled plasma (ICP). Majority of the serious corrosion damage was observed near the turbulator located in the upper flue tube. ICP analysis of the boiler water revealed oxide formation of sodium chloride in the lower end part of the flue tube. A cross-sectional view of the turbulator revealed the presence of double-layers of the oxide film, indicating environmental change during operation associated with water leakage. The outer surface of the turbulator consisted of the acid oxides such as $NO_x$ and $SO_x$ along with sodium and chloride ions. Dew-point corrosion is hypothesized as the main cause for the formation of acid oxides in the region of contact of the flue tube and the turbulator.

• Environmental Analysis Health and Toxicology
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• 제28권
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• pp.9.1-9.5
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• 2013

Objectives Geographic Information Systems (GIS) is a powerful tool for assessing exposure in epidemiologic studies. We used GIS to determine the geographic extent of contamination by perfluorooctanoic acid, C8 (PFOA) that was released into the environment from the DuPont Washington Works Facility located in Parkersburg, West Virginia. Methods Paper maps of pipe distribution networks were provided by six local public water districts participating in the community cross-sectional survey, the C8 Health Project. Residential histories were also collected in the survey and geocoded. We integrated the pipe networks and geocoded addresses to determine which addresses were serviced by one of the participating water districts. The GIS-based water district assignment was then compared to the participants' self-reported source of public drinking water. Results There were a total of 151,871 addresses provided by the 48,800 participants of the C8 Health Project that consented to geocoding. We were able to successfully geocode 139,067 (91.6%) addresses, and of these, 118,209 (85.0%) self-reported water sources were confirmed using the GIS-based method of water district assignment. Furthermore, the GIS-based method corrected 20,858 (15.0%) self-reported public drinking water sources. Over half (54%) the participants in the lowest GIS-based exposure group self-reported being in a higher exposed water district. Conclusions Not only were we able to correct erroneous self-reported water sources, we were also able to assign water districts to participants with unknown sources. Without the GIS-based method, the reliance on only self-reported data would have resulted in exposure misclassification.

• 한국동굴학회:학술대회논문집
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• 한국동굴학회 2004년도 전반기 학술발표대회
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• pp.67-73
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• 2004

• 한국농공학회논문집
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• 제62권2호
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• pp.111-120
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• 2020

This study assessed the reliability of the agricultural water supply based on future climate change scenarios, and suggested plans to improve the reliability in order to promote the adaptability of irrigation water in agricultural reservoirs to climate change. The assessment of agricultural water supply reliability was performed on reservoirs which had a lower water quantity than their design basis and which had recently been subject to drought. In other words, from the irrigation districts of main intake works among the reservoirs managed by the Korea Rural Community Corporation, 1~2 districts in each province-that is, a total of 13 districts -that were recently designated as a district for securing agricultural water (drought prevention district) were selected. Climate change scenarios were applied to the selected districts to analyze their future water supply reliability compared to the current level. All districts selected showed a drought frequency of 4 years or shorter, which demonstrated the need to establish climate change response plans. As plans for responding to climate change, a plan that utilizes supplemental intake works to reduce the area of the irrigation districts of main intake works, and another one that increases the capacity of main intake works were adopted to reanalyze their water supply reliability. When the area of the irrigation districts of main intake works was reduced by about 30~40%, the drought frequency dropped to more than 10 years, securing the reliability of water supply. To secure the reliability by increasing the capacity of main intake works, it was calculated that about 19,000~2,400,000 tons need to be added to each reservoir. In addition, climate change response plans were suggested to improve the reliability of the water supply in each district based on the results of economic analysis.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2007년도 하계학술발표대회 논문집
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• pp.16-16
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• 2007

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2004년도 하계학술발표 논문집
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• pp.224-224
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• 2004

• 한국농공학회:학술대회논문집
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• 한국농공학회 2003년도 학술발표논문집
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• pp.287-290
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• 2003

To devise better development plan, survey was conducted about current Farmer's irrigation Practice on upland in the Youngsan River Irrigation Project District IV. Major upland crops are garlic and onion in this region. Currently, upland irrigation is conducted using ground water. It is found that irrigation interval is $2{\sim}3$ day for dry-field rice and $3{\sim}7$ days for other crop, in general. Whole day is required to irrigate for many farmers due to lack of facilities and water source. Farmers have no intention to change staple crops even after completion of Irrigation Project of Youngsan River District IV.