• 상하수도학회지
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• 제26권3호
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• pp.383-397
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• 2012

In this study, a System Dynamics (SD) simulation model for the efficient operations of an industrial water supply system was developed by investigating the feedback loop mechanisms involved in the operations of the system. The system was modeled so that as demand is determined the water supply quantity of intake pumping stations and dams are allocated. The main feedback loop showed that many variables such as the combinations of pump operation, unit electric power(kWh/$m^3$), unit electric power costs(won/$m^3$), water level of water way tunnel, suction pressure and discharge of pumping station, and tank and service reservoir water level had causal effects and produced results depending on their causal relationship. The configurations of the model included an intake pumping station model, water way tunnel model, pumping station model (including the tank and service reservoir water level control model), and unit electric power model. The model was verified using the data from the case study industrial water supply system that consisted of a water treatment plant, two pumping stations and four dams with an annual energy costs of 5 billion won. It was shown that the electric power costs could have been saved 7~26% during the past six years if the operations had been based on the findings of this study.

• 설비공학논문집
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• 제14권11호
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• pp.880-889
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• 2002

The purpose of the present study is to examine the factors affecting the heat transfer limitations of screen mesh heat pipe for electronic cooling by theoretical analysis. Diameter of pipe was 6 mm, and mesh numbers are 50, 100, 150, 200 and 250 and water was selected as a working fluid. According to the change of mesh number, wick layer, inclination and saturation temperature, capillary pressure, pumping pressure, liquid friction coefficient in wick, vapor friction coefficient, capillary limitation, entrainment limitation, sonic limitation and boiling limitation we analyzed by theoretical design method of a heat pipe. As some results, the capillary limitation in small diameter of heat pipe is largely affected by mesh number and wick layer.

• 환경영향평가
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• 제12권3호
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• pp.189-198
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• 2003

본 연구는 수지해석(數値解析)을 이용하여 상관우물들의 분포를 갖는 집수역에서 수질을 고려하지 않은 상태의 지하수양수능을 평가하는 것을 목적으로 한다. 연구지역은 일본(日本)의 미야께지마(삼탁도)이며, 미야께지마는 최근에 이르기까지 화산분화(火山噴火)가 계속되고 있는 화산섬으로 수문지질학적(水文地質學的)으로 매우 복잡한 구조를 갖고 있다. 각각의 우물들에 대한 양수능은 개별(個別)양수에 의해서 구해진 IMY(i,t)로써 추정되었으며, 전(全) 연구지역의 양수능은 개별(個別)양수에 의해서 구해진SSMY(i,t)로써 추정되었다. 이러한 결과들은 미야께지마와 같은 화산섬에서 용수(用水)공급을 위한 계획의 수립에 있어서 확실한 공급원의 확보에 이용될 수 있다. 동시양수의 경우, 우물 5와 6에서의 양수는 타이로이께(대로지(大路池))부근에 존재하던 지하수가 연구지역의 내부에 까지 침투하는 것에 대한 장해(障害)우물로써 작용했다. 그러므로, 본 연구는 질적(質的), 양적(量的) 측면에서 용수공급을 위한 지하수의 최적(最適)관리방법으로써 동시양수를 제안한다.

• Current Photovoltaic Research
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• 제9권2호
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• pp.51-58
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• 2021

Solar water pumping system (SWPS) is reliable and beneficial for Indian farmers in irrigation and crop production without accessing utility. The capability of easy installation and deployment, makes it an attractive option in remote areas without grid access. The selection of portable solar based pumps is pertaining to its longer life and economic viability due to lower running cost. The work presented in this manuscript intends to demonstrate performance analysis of portable systems. Consequent investigation reveals PSWS as the emerging option for rural household and marginal farmers. This can be attributed to the fact that, a considerable portion (around 45.7%) of the country's land is farmland and irrigation options are yet to reach farmers who entirely rely on rain water at present for harvesting of the crops. According to census 2010-2011 tube wells are the main source for irrigation amongst all other sources followed by canals. Out of the total 64.57-million-hectare net irrigation area, 48.16% is accounted by small and marginal holdings, 43.77% by semi-medium and medium holdings, and 8.07% by large holdings. As per 2015-16 census data, nearly 100 million farming households would struggle to make ends meet. The work included in this manuscript, presents the performance of different commercial brands and different technologies of DC surface solar water micro pumping systems have been studied (specifically, the centrifugal and reciprocating type pumps have been considered for analysis). The performance of the pumping systems has been analyzed and data is evaluated in terms of quantity of water impelled for specific head. The reciprocating pump has been observed to deliver the best system efficiency.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2002년도 추계학술발표회
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• pp.277-279
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• 2002

In late of the 1980's, dramatic increase in water use caused over-exploitation of groundwater and deterioration of water quality in urban areas. To monitor quantity of groundwater resources and their qualities, local groundwater monitoring networks were established. Groundwater resources in urban areas are affected by various human activities including underground building construction (subway), pumping for water use, and pavements. Detailed analysis of the monitored groundwater data would provide some good implications for optimal and efficient management for groundwater resources in the urban area.

• 대한토목학회논문집
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• 제13권3호
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• pp.107-118
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• 1993

계속되는 도시화로 불투수성 면적이 증가되고, 환경변화에 의해 강우량이 증대되어 도시 저지대의 침수 우려가 더욱 가중되고 있는 실정이다. 따라서 서울특별시에서는 많은 예산을 들여 내수를 외수 쪽으로 강제배수시키는 빗물펌프장을 계속해서 보강 및 신설하고 있다. 그러나 상대적으로 경제적이라 할 수 있는 기존 빗물펌프장 시설의 적정 제어기법에 대한 연구나 투자는 전무한 상태라 할 수 있다. 본 연구는 퍼지제어기법을 적용하여 기존의 시설을 충분히 활용할 수 있는 기법을 개방하여 서울특별시 관내의 서로 다른 제원특성을 가진 57개의 유수지와 빗물펌프장에 적용하였다. 연구결과 현재의 펌프가동기준인 수위기준에 의한 펌프제어에 비하여 본 연구에서 적용한 퍼지제어기법이 전체 대상지점에 대하여 내수위를 같은 조건하에서도 충분히 낮출 수 있는 것으로 나타나 치수방재면에서 우수한 것으로 밝혀졌다.

• 한국농공학회논문집
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• 제47권5호
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• pp.3-13
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• 2005

The present study examined the 3 dimensional space distribution characteristics of sea water intrusion using data available from previous observations. For this study, we used 3D FEMWATER, which is a 3 dimensional finite element model. The target area was around Daechang-ri, Gimje-si, Jeollabuk-do. The area is relatively easy to formulate a conceptual model and has observation wells in operation for surveying sea water intrusion. Considering the uncertainty of numerical simulation, we analyzed sensitivity to hydraulic conductivity, which has a relatively higher effect. According to the result of the analysis, the variation of TDS concentration had an error range of $-1,336{\~}+107 mg/{\iota}$. Taking note that the survey data from observation wells were collected when the boundary between fresh water and sea water in the aquifer was in equilibrium, we set the range of time for numerical simulation and estimated the spatial distribution of TDS concentration as the range of sea water intrusion. According to the result of estimation, the spatial distribution of TDS concentration calculated when 1,440 days were simulated was taken as the range of sea water intrusion. Using the result of calculation, we can draw not only vertical views for a certain section but also horizontal views of different depth. These views will be greatly helpful in understanding the spatial distribution of the range of sea water intrusion. In addition, the result of this study can be used rationally in proposing an optimal quantity of water pumping through investigating the moving route of sea water intrusion over time in order to prevent excessive water pumping and to maintain an optimal number of water pumping wells per interval.

• 한국구조물진단유지관리공학회 논문집
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• 제20권3호
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• pp.122-129
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• 2016

본 연구에서는 고압송용 고유동콘크리트 개발을 위한 기초적인 연구의 일환으로 펌프압송시 압송관내 콘크리트가 받는 압력을 재현할 수 있는 가압장치를 개발하였다. 이를 통하여 펌프압송할 경우 발생되는 품질변화의 원인 중 압력에 의한 단위수량 감소에 중점을 두어 가압에 따른 콘크리트용 굵은골재의 흡수 특성 및 고유동콘크리트 내부 굵은골재의 흡수 특성을 평가하였으며, 고유동콘크리트의 가압 전 후 압축강도를 평가하였다. 실험결과, 250 bar의 높은 압력이 작용할 경우 부순굵은골재 및 강자갈의 흡수율은 표건 흡수율 이상으로 증가되지 않는 것으로 나타났으며, 경량굵은골재의 흡수율은 표건 흡수율 이상으로 증가되는 것으로 나타났다.

• 자원환경지질
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• 제43권2호
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• pp.149-162
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• 2010

K-1 유류비축기지는 인위적 지하 공동을 이용하기 때문에 주변 지하수계의 안정이 중요하다. 기지 주변의 지하수계 특성을 이해하기 위해 광역적 지하수 유동특성, 기지내 공간적 지하수위 분포 양상을 파악하였으며, 지하수 유동에 영향을 미치는 지질 요소를 검토하였다. 연구지역에서 지히수 유동에 크게 영향을 미칠 수 있는 지질구조적 특성은 2가지로서, 편마암-화강암 관입경계를 따라 재활성된 부분과 산성 암맥을 따라 발달한 단열 및 단층이다. 기지 내 4개 관측공들의 수위변동 양상을 검토한 결과, 대부분 강우와 지표수 유입 혹은 공동내 주입수에 의해 지하수위 변동이 영향을 받고 있는 것으로 나타났다. 이 연구에서는 기지 남쪽에 위치한 관정으로부터의 양수가 기지의 지하수위 변동에 미치는 영향에 대해 검토하였다. 산성 암맥을 따라 기지로부터 1.2km 남쪽에 위치한 지점에서의 양수작업은 관측 당시에 기지내 지하수위 변동에 영향을 미치지 않았으나, 모델링 결과에 의하면 $250\;m^3$/day 이상의 양수량으로 지속적인 양수작업이 진행되는 경우 지하수 시스템 안정을 위해 주의가 요구된다.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2002년도 학술발표회 발표논문집
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• pp.17-20
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• 2002

Hasa TM/TC system is composed of one control center, two reservoirs, six pumping stations and twelve canal systems. For this system we developed water management program which includes flood forecast program, drought reduction program, irrigation scheduling program and database program. With these program we expect that operators can improve the irrigation efficiencies of the irrigation systems due to the timely irrigation on a right place, in a proper quantity and reduce the cost of maintenance and reduce flood and drought damages of the Hasa district. In agricultural engineering respect, the databases including water level, rainfall, the amount of flowing can be useful to the researcher who make a study of hydrology and hydraulics in rural area. Water management program records all of the TM/TC data to MOB format file per 10 minutes.