• 한국지반신소재학회논문집
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• 제13권4호
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• pp.1-10
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• 2014

이 논문에서는 현장모형 실험을 통하여 동결온도에 따른 상수도관의 거동변형특성을 다루었다. 동결 온도 조건에 따라 상수도관에 미치는 동상압력과 Marston-Spangler 이론에 의한 동상 압력은 다소 차이를 나타내는 것을 보이며, Marston-Spangler이론만으로 관에 작용하는 하중을 고려하는 것은 안전측을 벗어날 수도 있다는 것을 염두 해야 한다. 또한 현장모형실험을 통한 상수도관의 변형률은 수치해석결과보다 작은 값을 나타내는 것을 확인하였다.

• 한국정보통신학회논문지
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• 제11권6호
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• pp.1207-1213
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• 2007

기존의 수도설비의 밸브실과 유량계의 관리는 기계적이고 숙련자의 경험적인 방식으로 이루어져 왔다. 그러나 USN 기반의 실시간 수도설비 모니터링 시스템을 활용한 시설물 관리는 안전성과 정확성을 제공함으로서 양질의 수자원을 관리하는데 기술적인 발전을 가져올 수 있다. 따라서 본 연구는 USN(Ubiquitous Sensor Network)과 CDMA(Code Division Multiple Access) 망을 이용한 수도 시설물의 안전 관리 시스템에 관하여 연구하였다. 수도 설비 중에서 밸브실과 유량계실을 대상으로 유량계, 압력센서, 진동센서, Co센서, 온 습도센서들의 RFID(Radio-frequency identification) 센서로 구성된 USN을 구성하고, USN으로부터 실시간으로 수도 시설물 정보 및 수(水)처리 측정 정보를 수집하여, CDMA망을 통해 원거리 관제 시스템에 전송한다. USN 기술을 이용하여 수도설비를 관리함으로서 현장에서의 편리성, 안전성, 정확성을 높여 더욱 효율적이고 안정적으로 깨끗한 수돗물을 공급하는데 기여할 수 있다.

• 한국농공학회논문집
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• 제63권5호
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• pp.95-105
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• 2021

Drought is a disaster that causes prolonged and wide scale damage. Recently, the severity and frequency of drought occurrences, and drought damage have been increased significantly due to climate change. As a result, a quantitative study of drought factors is needed to better understand and prevent future droughts. In the case of agricultural drought, several existing studies examine the economic damage caused by droughts and their causes, but these studies are not well suited to estimating crop-oriented agricultural drought damage and the factors that absolutely affect agricultural drought. This study determines which factors most affect agricultural drought. It examines meteorological factors and those related to agricultural water supplied by irrigation facilities. Rice paddy production per unit area is lower than the average from the last two years where agricultural drought occurred. We compare the relative frequency of agricultural drought impacts with irrigation facilities, effective reservoir storage, the number of water supply facilities, and the meteorological drought index such as Standardized Precipitation Index (SPI). To identify factors that affect agricultural drought, we correlate rice paddy production anomalies with irrigation water supply for the past two years. There was a high positive correlation between rice paddy production and irrigation water usage, and there was a low or moderate negative correlation between rice paddy production anomalies compared to the average of the past two years and SPI. As a result, agricultural water supply by irrigation facilities was judged to be more influential than meteorological factors in rice paddy production. This study is expected to help local governments establish policies related to agricultural drought response.

• 대한안전경영과학회지
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• 제17권4호
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• pp.161-169
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• 2015

A fire sprinkler system is very important to extinguish fire in the building. The sprinkler system initiates sprinkler discharge if the detection system identifies a developing fire and opens the pre-action valve. However, pre-action fire sprinkler systems mainly installed in the underground parking lot at the apartment complex do not properly operate at fire if the connection type of fire sprinkler systems does not properly installed and operated. This study identified the relationship between fire dispersion & damage and the connection type of water supply in the sprinkler system from many fire cases at the apartment complex in South Korea. In addition, this study also identified the water supply differences and characteristics between South Korea and foreign countries. The main purpose of this study is also to improve the water connection types in the sprinkler system that can reduce the potential failures of pre-action valve operation through electrical signal system. The study also suggests the improvement plan for water connection types in pre-action fire sprinkler system that can minimize potential failure of pre-action fire sprinkler system. The suggestions for revising the fire safe standard in South Korea includes letting the water supply pipe of sprinkler system water inlet connect to the second side of pre-action valve and the water flow device that can minimize potential failure of sprinkler system.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2017년도 학술발표회
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• pp.189-189
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• 2017

Climate changes have impacted to many sectors including water resources in Vietnam. Vietnam is agricultural development country having more than 6,000 earth dam reservoirs. These reservoirs play a very important role in flow regulation for water supply to economic sectors. In the context of undesirable impacts of climate change such as increasing temparature, evaporation, and changing rainfall and rainfall pattern, water demands and inflow to reservoirs also are being influenced. This leads to changes of resevoir exploitation effects that needs to be assessed for adaptation solutions. This article summarizes evaluations on climate change impacts to 16 reservoirs in 4 regions of North-West, North-East, Central Part, and Central Highland of Vietnam. Research results showed that in the context of climate change, safety of these reservoirs will be decreased from 8% to 20% in both water supply and flood control capacity.

• 상하수도학회지
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• 제36권5호
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• pp.261-273
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• 2022

In this study, we collect water control valves that have had accidents due to existing cracks, etc. are collected, and propose investigation items for strengthening the valve structural safety evaluation through a series of analyzes from valve specifications to physicochemical properties are proposed. The results of this study are as follows. First, there was a large variation in the thickness of the body or flange of the valves to be investigated, which is considered to be very important factor, because it may affect the safety of the valve body against internal pressure and the flange connected with the bolt nut. Second, 60% of the valves under investigation had many voids in the valve body and flange, etc. and the decrease in thickness due to corrosion was relatively large on the inner surface in contact with water rather than the outer surface. It is judged that the investigation of depth included voids is very important factor. Third, all valves to be investigated are made of gray cast iron foam, and therefore it is judged that there is no major problem in chemical composition. It is judged that the chemical composition should be investigated. Fourth, as a physical investigation item, the analysis of metal morphology structure seems to be a very important factor for nodular cast iron from rather than a gray cast iron foam water valve with a flake structure. As it was found to be 46.7~68.8% of the standard recommended by KS, it could have a direct effect on damage such as cracks, and therefore it is judged that the evaluation of tensile strength is very important in evaluating the safety of the valve.

• 한국농공학회논문집
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• 제63권1호
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• pp.27-35
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• 2021

KRC (Korea Rural Community Corporation) is in charge of about 3,400 agricultural reservoirs out of 17,240 agricultural reservoirs, and automatic water level gauges in reservoirs and canals were installed to collect reservoir and canal water level data from 2010. In this study, 10-minute water level data of 173 reservoir irrigation canals from 2016 to 2018 are collected, and discharge during irrigation season was calculated using rating curves. For estimation of water supply, irrigation water requirement was calculated with HOMWRS (Hydrological Operation Model for Water Resources System), and the summation of reservoir water storage decrease was calculated with daily reservoir storage data from RAWRIS (Rural Agricultural Water Resource Information System). From the results, the total yearly amount of irrigation water supply showed less than 10% difference than the irrigation water requirement. The regional analysis revealed that reservoirs in Jeollanam-do and Chungcheongnam-do supply greater irrigation water than average. On the contrary, reservoirs in Gyeongsangnam-do and Chungcheongbuk-do supply less than others. This study was conducted with a limited number of reservoirs compared to total agricultural reservoirs. Nevertheless, it can indicate irrigation water supply from agricultural reservoirs to provide information about agricultural water use for irrigation.

• 한국수자원학회논문집
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• 제37권7호
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• pp.569-579
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• 2004

최근 들어 지구온난화와 기상조건의 변화로 기후의 변동폭이 증가하면서 극심한 가물이 자주 발생하고 있다. 또한 기 개발된 용수원의 수질 오염, 물 분배에 관한 상류지역의 반대 및 지방자치단체간의 수리권 문제 등도 상류지역으로부터의 맑은 수자원 확보를 필요하게 만드는 요인이다. 따라서 이에 대한 용수공급 관리 방안의 필요성에 대한 인식이 부각되고 있으며, 수도권의 용수수요 변화에 대한 북한강 유역 댐의 용수공급 능력에 대한 적절한 검토가 필요한 실정이다. 본 연구에서는 북한강 유역 댐의 용수공급 가능성을 파악하고 적절한 용수 공급방안을 제시하기 위하여 shared vision 모형인 스텔라 소프트웨어를 이용한 모의 운영시스템을 개발하였다. 또한 이 모형에서는 수위에 따른 평균의 최소, 중간, 최대의 조건으로 3가지 Rule을 정하여 저수지의 운영곡선의 변화와 발전방류에 따른 안전 공급율 변화를 분석하였다.

• 한국농공학회논문집
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• 제66권3호
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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.

• 한국농공학회논문집
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• 제63권3호
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• pp.47-57
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• 2021

Drought monitoring over paddy field area is an important role as the frequency and intensity of drought due to climate change increases. This study analyzed the applicability of drought monitoring on paddy crops using MODIS-based field surveys. As a satellite-based drought index using evapotranspiration for quantitative drought determination, ESI (Evaporative Stress Index), was applied and calculated through the ratio of MODIS- based actual and potential evapotranspiration. For the irrigated areas of Idong, Gosam, Geumgwang, and Madun reservoirs the availability of irrigation water supply, ponding depth, precipitation, paddy growth were investigated for the paddy field within one grid of MODIS. In addition, the percentile-based ESI drought severity was calculated to compare the growth process of paddy and changes in the drought category of ESI. The Idong area was irrigated about a week later than other reservoirs for the period of water supply, transplanting, and water drainage and the ESI drought category tended to be different. The Gosam, Geumgwang, and Madun area expressed moderate drought prior to the farming season, and indicated normal as the water was supplied. During the water drainage, the drought category intensified, indicating that the water available on land was decreasing. These results demonstrated that the MODIS-based ESI could be an effective tool for agricultural drought monitoring over paddy field area.