• 한국지하수토양환경학회지:지하수토양환경
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• 제12권4호
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• pp.54-59
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• 2007

본 연구에서는 수학적 모델링을 통해 강우에 기인하는 지하수위 변동예측 준-해석학적 모델을 개발하였다. 개발된 모델은 홍천 지역의 지하수위 변동을 예측에 적용되었으며 이를 위하여 지하수 변동 관측자료 및 강우자료가 이용되었다. 개발된 모델은 비선형 파라미터 예측 코드를 활용하여 2003년 지하수위 변동을 예측하도록 적정되었으며 이렇게 최적화에 이용된 입력 파라미터는 그 다음해인 2004년 지하수위 변동을 예측하는데 활용되었다. 강우자료에 기초한 2004년 지하수위 변동 예측은 RMS 오차가 0.18 m로 관측지하수위의 표준편차가 0.44 m인 것으로 미루어 보았을 때 대체로 양호한 것으로 판단된다. 또한 본 연구에서는 개발된 모델을 이용하여 지표 피복의 변화에 기인하는 함양율 감소 시 발생되는 지하수위 변동 예측 및 양수에 의한 인공적인 지하수위 강하를 모사하는데 적용하였다. 본 연구의 결과는 보다 정확한 지하수위 변동 예측증 위해서는 지하수 함양율을 상수로 적용하는 것이 적절치 않으며 강우 패턴의 함수로 결정되어야 함을 보인다.

• 디지털산업정보학회논문지
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• 제12권3호
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• pp.231-257
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• 2016

Several efforts to replace the use of existing fossil energy resources have already been made around the world. As a result, a new industry of renewable energy has been created, and efficient energy distribution and storage has been promoted intensively. Among the newly explored renewable energy sources, the most widely used one is solar energy generation, which has a high market potential. An energy storage system (ESS) is a system as required. In this paper, the design and implementation of an ESS for the efficient use of power in stand-alone street lights is presented. In current ESS applied to stand-alone street lights, either 12V~24V DC (from solar power) or 110V~220V AC (from commercial power) is used to recharge power in systems with lithium batteries. In this study, an ESS that can support both solar power and commercial power was designed and implemented; it can also perform emergency recharge of portable devices from solar powered street lights. This system can maximize the scalability of ESSes using lithium batteries with efficient energy conversion, with the advantage of being an eco-friendly technology. In a ripple effect, it can also be applied to smart grids, electric vehicles, and new, renewable storage markets where energy storage technology is required.

• 디지털산업정보학회논문지
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• 제12권2호
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• pp.1-6
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• 2016

Several efforts to replace the use of existing fossil energy resources have already been made around the world. As a result, a new industry of renewable energy has been created, and efficient energy distribution and storage has been promoted intensively. Among the newly explored renewable energy sources, the most widely used one is solar energy generation, which has a high market potential. An energy storage system (ESS) is a system as required. In this paper, the design and implementation of an ESS for the efficient use of power in stand-alone street lights is presented. In current ESS applied to stand-alone street lights, either 12V~24V DC (from solar power) or 110V~220V AC (from commercial power) is used to recharge power in systems with lithium batteries. In this study, an ESS that can support both solar power and commercial power was designed and implemented; it can also perform emergency recharge of portable devices from solar powered street lights. This system can maximize the scalability of ESSes using lithium batteries with efficient energy conversion, with the advantage of being an eco-friendly technology. In a ripple effect, it can also be applied to smart grids, electric vehicles, and new, renewable storage markets where energy storage technology is required.

• 농촌계획
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• 제25권4호
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• pp.35-45
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• 2019

Korean agriculture experienced rapid changes in its production structure to respond fluctuations on external conditions, and these changes have increased the dependence between agricultural resources and negative environmental externalities from agricultural production. As a tool for managing agricultural resources and reducing negative environmental effects from agricultural production, this study employs water-energy-food nexus for integrated resource management. To show the necessity of an integrated approach, this study evaluated three policy scenarios including changes in capital interest, water capacity, and energy cost. The results show that three scenarios have unintended consequences for farmers' incomes and their use of resources. Also the unintended consequences of government policies also affected farms' vulnerability to environmental changes. In particular, the expansion of financing for the establishment of non-circulating water curtain facilities did not have a significant effect on the crop switching of farms. In addition, increasing the amount of available water through the aquifer recharge project leads to the installation of non-circulating water curtain facilities in zucchini farm. It raises dependence on groundwater in agricultural production, thereby increasing farmers' vulnerability to groundwater shortages. These results imply that the agricultural sector needs to consider the interrelationship between agricultural resources when designing or evaluating policies.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2002년도 총회 및 춘계학술발표회
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• pp.110-113
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• 2002

Statistical- based, principal component analysis (PCA) was applied to chemical data from two underground storage systems containing LPG to assess the usefulness of such technique at the initial stage (Pyeongtaek) or middle stage (Ulsan) of hydrochemical studies. For the first case, both natural and anthropogenic contamination characterize regional groundwater. Saline water buffered by Namyang lake affects as a natural factor, whereas cement grouting influence as an artificial factor. For the second study area, contaminations due to operation of LPG caverns, such as disinfection activity and cement grouting effect, deteriorate groundwater quality. This study indicates that principal component analysis would be particularly useful for summarizing large data set for the purpose of subsurface characterization, assessing their vulnerability to contamination and protecting recharge zones.

• 한국수자원학회논문집
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• 제40권5호
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• pp.419-430
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• 2007

지표수와 지하수의 통합모델링은 지속가능한 수자원과 수질개선에 대한 점증하는 요구를 만족시키기 위해 점차 중요성을 더해가고 있다. 본 연구에서는 준분포형 유역유출모형인 SWAT과 완전분포형 지하수 모형인 MODFLOW의 통합모형을 무심천 유역에 작용하여 유역단위의 수문과정을 재생하였다. 모의결과 2001-2004년의 관측수문곡선과 모의유량수문곡선간의 적합이 잘 나타나는 한편 계산된 지하수위 분포와 관측지하수위와의 보정결과도 양호하게 나타났다. 통합모형은 서로 다른 기간의 강수평균이 하천유출, 침루, 함양, 지하수 유출의 동적과정에 미치는 영향을 평가하는데도 활용되었다. 나아가, 윌별강수와 각 수문성문간의 관계를 살펴보고 함양량의 시공간적 변동성을 분석하기 위한 종합적인 모의를 수행한 결과, 수문성분 상호간에 높은 상관성을 보이며 소유역경사, 토지이용, 토양종류 같은 유역특성의 비균질성이 함양량의 공간변화에 주요 원인인 것으로 확인됐다. 통합모형은 시공간적으로 변모하는 유역단위의 지표수와 지표하 수문과정을 전반적으로 잘 표현하는 것으로 나타났다.

• 한국수자원학회논문집
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• 제33권1호
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• pp.51-59
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• 2000

시계열모형과 시차분포모형을 결합한 동적모형을 이용하여 강우량과 지하수위의 관계를 파악하였다. 시차에 따른 현재 및 과거 강우량과 과거 지하수위를 독립변수로 하여 동적모형을 구성하였다. 지하수위에 미치는 시차에 다른 강우량의 영향을 Almon 다항식으로 분포시켜 시차분포모형의 매개변수를 추정하였다. IHP 대표유역의 방림과 탄부의 지하수위관측소에서 적용된 동적모형은 강우량에 따른 지하수위를 매우 잘 재현해 주고 있으며, 지하 수위의 예측에도 이용할 수 있음을 확인하였다. 또한 모형의 매개변수는 대수층의 지질특성을 반영하고 있다. 지하수위는 1일전 강우량과 가장 큰 연관성이 있으며, 방림의 경우 18mm/일, 탄부의 경우 30mm/일 이하의 강우량에서는 지하수위의 변동에 큰 영향이 없었다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제18권6호
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• pp.8-17
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• 2013

The contamination of chlorinated ethenes at an industrial complex, Wonju, Korea, was examined based on sixteen rounds of groundwater quality data collected from 2009 to 2013. Remediation technologies such as soil vapor extraction, soil flushing, biostimulation, and pumping-and-treatment have been applied to eliminate the contaminant sources of trichloroethylene (TCE) and to prevent the migration of TCE plume from remediation target zones. At each remediation target zone, temporal monitoring data before and after the application of remediation techniques showed that the aqueous concentrations of TCE plume present at and around the main source areas decreased significantly as a result of remediation technologies. However, the TCE concentration of the plumes at the downstream area remained unchanged in response to the remediation action, but it showed a great fluctuation according to seasonal recharge variation during the monitoring period. Therefore, variations in the contaminant flux across three transects were analyzed. Prior to the remediation action, the concentration and mass discharges of TCE at the transects were affected by seasonal recharge variation and residual DNAPLs sources. After the remediation, the effect of remediation took place clearly at the transects. By tracing a time-series of plume evolution, a greater variation in the TCE concentrations was detected at the plumes near the source zones compared to the relatively stable plumes in the downstream. The difference in the temporal profiles of TCE concentrations between the plumes in the source zone and those in the downstream could have resulted from remedial actions taken at the source zones. This study demonstrates that long term monitoring data are useful in assessing the effectiveness of remediation practices.

• 한국시스템다이내믹스연구
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• 제13권4호
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• pp.33-55
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• 2012

The research is to identify important diffusion factors and their effects on green car diffusion process using system dynamics perspectives and a causal-loop analysis. Through a deep review on previous research, we have found the important factors of green car diffusion process. Price, driving range, network effect, recharge system, fuel cost had important facilitation on consumer attraction and green car diffusion. Based on the review, we have constructed a causal loop diagram explaining hybrid car diffusion process. We have found 3 important reinforcing loops in the causal loop diagram. Loop for learning & economies of scale(supply side), loop for network effect(consumer side), and loop for battery development(technology side) had most significant roles in the whole diffusion process. Through a deliberate analysis on the 3 causal loops, we have found meaningful results. First, there seems to exist a critical mass in the diffusion. Second, of the 3 loops, the battery technology had most significant role. Third, not consumer installed base but sales must be a standard to decide whether the critical mass is achieved or not. Based on these findings, several meaningful implications are suggested for the government and corporations related to the green car industries.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2002년도 총회 및 춘계학술발표회
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• pp.133-136
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• 2002

제주도에 내리는 강수의 동위원소 조성의 시공간적인 분포를 파악하고 지하수 함양과의 관련성을 연구하기 위하여, 한라산의 남측과 북측 사면에 8개의 강수채수기를 설치하여 1년 동안 (2000. 9 ~ 2001. 8) 월강수를 채취하였다. 연구기간 동안에 강수량은 남쪽사면이 북쪽사면보다 약 37% 더 많았다. 강수의 산소동위원소 조성은 온도효과를 거의 보이지 않았다. 그러나 여름 강우에는 우량효과가 매우 뚜렷하였다. 고도가 높아지면서 강수의 동위원소 조성이 낮아지는 고도효과가 남측과 북측사면에서 모두 뚜렷이 관찰되었다. 가중평균값으로 볼 때 북측사면 강수의 동위원소 조성이 남측사면 강수보다 약 0.5$^{0}$ $_{00}$ 낮은 것이 관찰되었는데 이는 비그늘효과(rain shadow effect) 때문인 것으로 해석된다. 다른 지역에 비하여 북부지역 지하수 동위원소 조성이 상대적으로 결핍되어 있는 것은 기존 연구 결과처럼 지하수 이동속도가 빠르기 때문에 일어나는 현상이 아니고 지하수로 함양된 강수의 원래의 동위원소 조성을 반영하기 때문인 것으로 해석된다.다.