• Journal of The Korean Society of Agricultural Engineers
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• v.66 no.3
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• pp.39-51
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• 2024

To effectively implement the integrated water management policy outlined in the National Water Management Act, it is essential to analyze agricultural water supply and demand at both basin and water district levels. Currently, agricultural water is primarily distributed through open canal systems and controlled by floodgates, yet the utilization-to-supply ratio remains at a mere 48%. In the case of agricultural water, when analyzing water balance through existing national basin water resource models (K-WEAP, K-MODISM), distortion of supply and regression occurs due to calculation of regression rate based on the concept of net water consumption. In addition, by simplifying the complex and diverse agricultural water supply system within the basin into a single virtual reservoir, it is difficult to analyze the surplus or shortage of agricultural water for each field within the basin. There are limitations in reflecting the characteristics and actual sites of rural water areas, such as inconsistencies with river and reservoir supply priority sites. This study focuses on the development of a model aimed at improving the deficiencies of current water balance analysis methods. The developed model aims to provide standardized water balance analysis nationwide, with initial application to the Anseo standard watershed. Utilizing data from 32 facilities within the standard watershed, the study conducted water balance analysis through watershed linkage, highlighting differences and improvements compared to existing methods.

• Journal of Oral Medicine and Pain
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• v.6 no.1
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• pp.45-56
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• 1981

The demand and supply of dentists was studied by the econometrical model. It is based on the data of socio-economic-cultural statistic from 1967 to 1977; GNP, average monthly consumption expenditure per household, consumption of milk, populat ion, consumption of energy, water supply per person a day and entrance rate of senior high school. 1.The curved regression equation and multiple correlation coefficient (R)between the number of dentists(Y) and year (x)were $Y=4,122(1.06)^x$,R=0.995. 2. From 1982 to 1985, expected demand and expected supply will be approximately balanced. But dentists will be oversupplied conspicuously from the year of 1986. Such a oversupply will be remarkably incresed to the amount of 1860 in the year of 2000. 3. It is seemed that balanced number of graduates of dental colleges will be about 350 to the year of 1985, from the year of 1986, will be about 450, from the year of 1981, will be about 600 and from the year of 1996, will be about 700. 4. In 2000, persons served by each dentist will be 3550 by the expected supply and 4120 by the expected demand.

• Journal of Soil and Groundwater Environment
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• v.17 no.2
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• pp.62-70
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• 2012

Rainfall, on Jeju Island varies regionally in relation to Mt. Halla with higher rainfall within southern area and lower in western area, and its variability is expected to expand according to the climate change scenario. Non-parametric trend analysis for rainfall, using both historic (1971-2010) and simulated (2011-2100) data assuming the A1B emissions scenario, shows regionally increasing trends with time. In perspective of agricultural land use, area for market garden including various crop types with high water demand is increasing over the Island, especially in the western area with lower rainfall compared to southern area. On the other hand, area for fruit including mandarin and kiwi with low water demand is widely distributed over southern and northern part having higher rainfall. These regional disparity of water demand/supply may be more affected by extreme events such as drought and heavy rainfall that has not yet been considered. Therefore, it is necessary to make policies for water resource management considering both demand and supply in different regions with climate change impacts over Jeju Island.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.323-327
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• 2006

During the past decades in South Korea, there have been several projects to reduce water demand and save water for paddy irrigation system by automation. This is called as intensive water management system by telemetering of paddy ponding depth and canal water level and telecontrol of water supply facilities. This study suggests a method of constructing topology-based irrigation network system using GIS tools. For the network modeling, a typical agricultural watershed included reservoirs, irrigation and drainage canals, pumping stations was selected. ArcHydro tools composed of edge, junction, waterbody and watershed were used to construct hydro-network. ArcHydro Model was then designed and the network was successfully built using the HydroID. Visualization using ArcHydro tools could display table property of each object. ArcHydro Model was linked to Agricultural Water Demamd and Supply Estimation System (AWDS) which developed by Korea Rural Community and Agriculture Corporation (KRC) to extract information of the study area. And menu of supply facilities information, demand analysis and supply analysis constructed for information acquisition and visualization of acquired informations.

• Journal of Soil and Groundwater Environment
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• v.22 no.4
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• pp.60-70
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• 2017

As water sources become more vulnerable to the effects of climate change such as drought and contamination, the diversification of water sources is important for securing water supply. This study examines the properties of five water sources for public supply, including river and river-bed water, dams, reservoirs, and groundwater, while ensuring that the quantities available from such sources are stable and the water itself is safe for use. This study also analyzes the power, chemical, repair and maintenance, and labor costs associated with each water source. The results demonstrate that groundwater has high potential as a water source because it is readily available (about $12.89billion\;m^3/yr$), but only a small portion of it is currently used. Analyses indicated that groundwater is the most efficient source of water to meet water demand below $1,000,000m^3/yr$, which covers 62.5% of water supply facilicities. With the implementation of groundwater dams, groundwater can become cost-efficient even for larger water demand. Additionally, the water source protection areas are the smallest for groundwater among the five water sources. In conclusion, the use of groundwater as an alternative water source is feasible becasue it is readily available, safe, cost-efficient, and requires the lowest amount of environmental regulations for the diversification of water supply sources.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2005.10a
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• pp.318-323
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• 2005

This research evaluates agricultural water supply capabilities for water computing demand and supply for water of the whole water system of Ansung stream by carrying out basin water balance classified by irrigation facility of water system of Ansung stream.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.20 no.6
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• pp.394-399
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• 2008

There are many attempts to use a fuel cell system as a residential power generation system. The purpose of this study is to investigate the optimal design of a water tank for a hot water system when the fuel cell co-generation system is combined with a domestic hot water supply system. The demands of hot water supply per month per home are investigated in Busan for a year. It showed somewhat large differences between the actual demand and the designed demand of hot water, but the actual capacity of hourly averaged hot water demands is analyzed as $60{\ell}/h$ in this study based on the actual demand. The experiments are performed in the various inlet and outlet locations of nozzles, and the hot water consumption rates. The experimental results are showed that the optimal capacity of the water tank is $200{\ell}$ when the thermal efficiency, the storing capacity of hot water and the space for installation are considered.

• Proceedings of the Korea Water Resources Association Conference
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• 2001.05a
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• pp.15-24
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• 2001

This study introduces an integrated decision support system (DSS) for the water supply system in Fukuoka City, Japan. The objective is to conceive a comprehensive tool that may aid decision-makers to derive the best water supply alternatives from a multi-reservoir system in order to minimize the long-term drought damages and threat of water shortage. The present DSS consists of graphical user interface (GUI), a database manager, and mathematical models for runoff analysis, water demand forecasting, and reservoir operation. The methodology applied explicitly integrates the drought risk assessment based on the concept of reliability, resiliency, and vulnerability, as constraints to derive the management operation. The application of the DSS to the existing water supply system in Fukuoka City was found to be an efficient tool to facilitate the examination of a sequence of water supply scenarios toward an improved performance of the actual water supply system during periods of drought.

• Journal of The Korean Society of Agricultural Engineers
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• v.54 no.2
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• pp.37-46
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• 2012

The change of rainfall pattern and hydrologic factors due to climate change increases the occurrence probability of agricultural reservoir water shortage. Water supply assessment of reservoir is usually performed current reservoir level compared to historical water levels or the simulation of reservoir operation based on the water budget analysis. Since each reservoir has the native property for watershed, irrigation district and irrigation water requirement, it is necessary to improve the assessment methods of agricultural reservoir water capability about water resources system. This study proposed a practical methods that water supply vulnerability assessment for an agricultural reservoir based on a concept of probabilistic reliability. The vulnerability assessment of water supply is calculated from probability distribution of water demand condition and water supply condition that influences on water resources management and reservoir operations. The water supply vulnerability indices are estimated to evaluate the performance of water supply on agricultural reservoir system, and thus it is recommended a more objective method to evaluate water supply reliability.

• Journal of The Korean Society of Agricultural Engineers
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• v.55 no.4
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• pp.45-53
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• 2013

Efficient water operation and management of an irrigation system plays an important element in the sustainability of irrigated agriculture. An agricultural water is delivered in many open canals of irrigation delivery system by reservoirs. The poor water distribution and management in an irrigation system is a major factor leading to low water efficiency. It is necessary to compare the estimated irrigation demands with the actual water supplies for decision making to maintain the water supply according to demand strategy. Smarter water management, new technologies and improvement of water management system, is essential to solve the problem of water efficiency and availability. In this paper, the irrigation efficiencies according to water delivery performance indicator were measured with automatic water gauge at irrigation canals, and calculated from spatial and temporal distribution of water supply for the lack of planning in water delivery. The analysis of results are obtain an insight into possible improvement methods to develop canal water management policies that enable irrigation planners to optimally manage scarce available water resources.