• 한국농공학회논문집
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• 제64권6호
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• pp.13-23
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• 2022

The purpose of this study was to analyze the impact of greenhouse cultivation area and groundwater level changes due to the water curtain cultivation in the greenhouse complexes, which are mainly situated along rivers where water resources are easy to secure. The groundwater observation network in Miryang, Gyeongsangnam-do, located downstream of the Nakdong River, was selected for the study area. We classified the groundwater monitoring well into the greenhouse (riverside) and field cultivation areas (plain and mountain) to compare the groundwater impact of water curtain cultivation in the greenhouse complex. The characteristics of groundwater level changes classified by terrain type were analyzed using the observed data. Riverside wells have significant permeability coefficients and are close to rivers, so they are greatly affected by river flow and precipitation changes so that water level shows a specific pattern of annual changes. Most plain wells do not show a constant annual change, but observation wells near small rivers and small-scale greenhouse cultivation areas sometimes show annual and daily changes in which the water level drops during winter. Compared to other observation wells, mountain wells do not show significant yearly changes in water level and show general characteristics of bedrock aquifer well with a low permeability coefficient.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2003년도 학술발표회논문집(2)
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• pp.611-614
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• 2003

Yi-dong experimental basin is operated for research on the rural basin characteristics and accumulation of a long term data by hydrological observation equipments. It is basin area 9,440ha, length 14.4km and slope 0.67%. Hydrological observation network is constructed of rainfall meter 4points, reservoir storage level 3points and river water level 2points.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2002년도 총회 및 춘계학술발표회
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• pp.351-356
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• 2002

Groundwater recharge rate was estimated by applying the groundwater level fluctuation method utilizing Theis (1937) approach with specific yield estimation technique of Shevenell (1996) and the temperature method using observed data from National Groundwater Observation Stations. Results based on analysis of water level observation data of 10 alluvium wells reveal that the recharge rates for 5 wells of Kum river area range 3.7~25.0% and those for 5 wells of Nakdong river area range 3.6~21.7%. Results obtained from the temperature method based on water temperature data indicated that the upward flow resulted from evapotranspiration is dominant for 4 wells of the Kum river area and 5 wells of the Nakdong river area. The other wells showed the downward flow which is related to groundwater recharge in these areas.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2003년도 추계학술대회 논문집
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• pp.340-345
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• 2003

This study, as a basic study for establishing a influence forecasting/estimating model when drain the deep sea water to the ocean after using it, carried out studies as follows; 1) estimating the amount of river discharge and pollutant loads inflowing into the developing region of deep sea water in East Sea, Korea 2) a field observation of tidal current, vertical distribution of water temperature and salinity, and 3-D numerical experiment of tidal current to analysis physical oceanographic status. The amount of river discharge flowing into the study area was estimated about $462.6{times}10^{3}m^{3}/day$ of daily mean in 2002 year. annual mean pollutant load of COD, TN and TP were estimated 7.02 ton-COD/day, 4.06 ton-TN/day and 0.39 ton/day, respectively. Field observation of tidal current results usually show about $20{\sim}40cm/sec$ of current velocity at the surface layer, it indicated a tendency that the current velocity decreases under 20cm/sec as the water depth increases. We could find a stratification within approximately the depth of 30m in field observation area, and the depth increases. We could find a stratification within approximately the depth of 30m in field observation area, and the differences of water temperature and salinity between the surface layer and bottom layer were about $18^{\circ}C$ and 0.8 psu, respectively. On the other hand, we found that there was a definite as the water mass of deep sea water about 34 psu of salinity.

• 한국농공학회논문집
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• 제65권6호
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• pp.93-103
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• 2023

This study aimed to analyze the impact of water curtain cultivation in the greenhouse complexes on groundwater's electric conductivity and water temperature. The greenhouse complexes are mainly situated along rivers to secure water resources for water curtain cultivation. We classified the groundwater monitoring well into the greenhouse (riverside) and field cultivation areas (plain) to compare the groundwater impact of water curtain cultivation in the greenhouse complex. The groundwater observation network in Miryang, Gyeongsangnam-do, located downstream of the Nakdong River, was selected for the study area. As a result of analyzing the electric conductivity and water temperature, the following differences were found in the observed characteristics by region. 1) The electric conductivity and water temperature of the riverside area, where the permeability is high and close to rivers, showed a constant pattern of annual changes due to the influence of river flow and precipitation. 2) The flat land in general agricultural areas showed general characteristics of bedrock observation in the case of water temperature. Still, it seemed more affected by the surrounding well's water use and water quality. The electric conductivity did not show any particular trend and was influenced by the surrounding environment according to the location of each point.

• 한국태양에너지학회 논문집
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• 제34권4호
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• pp.111-122
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• 2014

The purpose of this study is to understand daily variation of short-wave radiation trends according to the state of surface and observation of atmosphere conditions in downtown and suburban observation area. The followings are main results from this study. 1) We found out daily air temperature variation of downtown is less than that of suburban area because of bigger heat capacity of artificial elements such as massive buildings and pavements. 2) It is more effective to estimate of air condition by water vapor pressure than relative humidity in the atmosphere. 3) The difference of solar radiation ratio between downtown and suburban area is dependant on different atmosphere conditions at two observation stations.

• 한국해양환경ㆍ에너지학회지
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• 제15권3호
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• pp.208-218
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• 2012

수면에서의 마이크로웨이브 후방산란 수치 시뮬레이션 기법을 개발하였다. 수치 시뮬레이션은 수조나 실해역 실험의 대체수단으로서, 수면에서의 마이크로웨이브 후방산란 과정의 이해, 마이크로웨이브 레이더를 이용한 수면 관측시스템과 관측방법의 평가에 이용된다. 이 논문에서는 다양한 수면 조건에 대한 수치 시뮬레이션의 적용 예와 수치 시뮬레이션의 유용성에 대해서 기술하였다. 적용 예로서, 고정안테나 펄스 도플러 레이더의 1) 도플러 이미지, 2) 레이더 조사폭 영향, 3) 하천 수위 관측과, 4) 합성 개구 레이더 (SAR) 의 해면 이미지를 보여준다. 해면으로부터의 마이크로웨이브 후방산란 수치 시뮬레이션을 통하여, 1) 파랑계측에 있어서 펄스 도플러 레이더의 주파수 변조 이미지가 진폭 변조 이미지에 비해서 유용함을 보였다. 2) 연속파 레이더를 이용한 파랑계측에 있어서의 레이더 해면 조사폭의 영향에 대한 Rheem[2008]의 보고와 관련해, 레이더 조사폭이 도플러 스펙트럼에 미치는 영향을 조사하여, 파랑계측에 적합한 레이더의 조사 조건을 보였다. 3) 펄스 도플러 레이더를 이용한 해면 조위관측 알고리듬을 하천의 유속과 수위 추정에 응용함에 있에서, 알고리듬의 적용성과 계측성능을 평가했다. 4) SAR 이미지 생성 메케니즘의 이해와 SAR 이미지를 이용한 해면 관측 알고리듬의 평가를 위해, 수치 시뮬레이션을 이용하여 해면의 SAR 이미지를 생성하였다.

• 한국해양학회지:바다
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• 제6권2호
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• pp.49-62
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• 2001

Cochlodinium polykrikoides 유해성적조 발생지역인 한국 남해 나로도와 소리도 사이 해역의 물리적인 환경을 연구하기 위하여 1998년 5월31일부터 9월 24일까지 7회에 걸쳐 수온 및 염분을 관측하였다. 연구해역의 표층에서 30m깊이까지의 수층에서는 관측 초기인 춘계부터 하계로 갈수록 수온이 증가하고 염분은 낮아지는 물성의 계절적인 변화가 뚜렷하였는데 수층전체의 평균수온은 총 조사기간동안 $6^{\circ}C$ 증가하고 평균염분은 2.71 psu 낮아졌다. 관측된 평균염분의 변화는 연구해역의 강수와 인접육지에 의해 공급될 수 있는 담수량만으로는 설명할 수 없었으며, 남해외해역으로부터 유입되는 저염수에 의해 일어났을 것으로 해석되었다. 이 해역에서 적조의 발생시기, 진행시기 및 적조가 사라진 시기에 염분의 공간적인 분포가 다른 특징을 보였으며, 특히 적조가 사라진 시기에는 염분이 직전 시기에 비해 크게 낮아지고 수층구조도 직전시기의 성층구조에서 혼합층구조로 변화하였는데, 이와 같은 변화는 남해 외해역으로부터 저염수의 유입으로만 설명할 수 있었다. 이로부터 물리적인 해수유동이 이 해역에서 적조가사라진 주요한 원인의 하나로 제시되었다. 본 연구결과는 차후 남해 연안역의 적조현상을 이해하기 위해서는 인접 육지로부터 유입되는 환경적 요소들은 물론 대상해역을 포함한 남해 외해역의 해수순환특성, 그리고 해수순환에 의해 이송되는 해수의 물리, 화학 및 생물학적 요소를 종합적으로 연구해야할 필요성을 시사한다.

• 한국농공학회논문집
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• 제65권2호
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• pp.1-11
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• 2023

This study analyzed the impact of greenhouse cultivation area and groundwater level changes due to the water curtain cultivation in the greenhouse complexes. The groundwater observation data in the Miryang study area were used and classified into greenhouse and field cultivation areas to compare the groundwater impact of water curtain cultivation in the greenhouse complex. We identified the characteristics of the groundwater time series data by the terrain of the study area and selected the optimal model through time series analysis. We analyzed the time series data for each terrain's two representative groundwater observation wells. The Seasonal ARIMA model was chosen as the optimal model for riverside well, and for plain and mountain well, the ARIMA model and Seasonal ARIMA model were selected as the optimal model. A suitable prediction model is not limited to one model due to a change in a groundwater level fluctuation pattern caused by a surrounding environment change but may change over time. Therefore, it is necessary to periodically check and revise the optimal model rather than continuously applying one selected ARIMA model. Groundwater forecasting results through time series analysis can be used for sustainable groundwater resource management.

• 한국해양공학회지
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• 제19권1호
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• pp.14-19
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• 2005

As a basic study for establishing the input conditions of a forecasting/estimating model, used for deep-sea water drainage to the ocean, this study was carried out as follows: 1) estimating the amount of river discharge and pollutant loads into the developing region of deep sea water in the East Sea, Korea, 2) a field observation of tidal current, vertical water temperature, and salinity distribution, 3) 3-D numerical experiment of tidal current to analyze the physical oceanographic status. The amount of river discharge flowing into this study area was estimated at about $462.7{\times}103 m\^3/day$ of daily mean in 2002. Annual mean pollutant load of COD, TN, and TP were estimated at 7.02 ton-COD/day, 4.06 ton-TN/day, and 0.39 ton/day, respectively. Field observation of tidal current normally shows 20-40cm/sec of current velocity at the surface layer, and it decreases under 20cm/sec as the water depth increases. We also found a stratification condition at around 30m water depth in the observation area. The differences in water temperature and salinity, between the surface layer and the bottom layer, were about 18 C and 0.8 psu, respectively. On the other hand, we found a definite trend of 34 psu salinity water mass in the deep sea region.