• Proceedings of the Korea Water Resources Association Conference
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• 2023.05a
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• pp.421-421
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• 2023

하구담수호는 하천의 출구점이 해양과 만나는 곳에 방조제를 건설하고 이를 통해 형성되는 인공호수이다. 출구점에 위치한 지리적 특성은 많은 수자원을 확보할 수 있지만 유역에서 발생하는 모든 유입량 및 오염물질이 유입되어 홍수위험 및 수질악화가 문제점으로 제시되고 있다. 담수호의 관리수위는 배수갑문 운영에 기초가 되는 수위로 용수공급, 홍수위험도를 고려하여 산정한다. 하지만 기후변화로 인해 가뭄, 홍수의 위험성이 커지고 있으며, 이를 고려하여 관리수위의 산정이 필요하다. 로버스트 의사결정 기법은 기후변화의 불확실성 하에서의 정책 결정을 위해 제시된 개념으로 불확실한 미래상황에 대하여 최적이 아닌 여러상황의 준수한 결과를 보이는 방법을 선정해 예상치 못한 상황에도 대비할 수 있는 것을 목적으로 한다. 본 연구에서는 담수호의 관리수위 산정을 위해 로버스트 의사결정 기법을 적용하였다. 관리수위 산정을 위해 미래 기후변화 시나리오는 CanESM5 GCM의 SSP1, 2, 3, 5 시나리오를 이용하였으며 담수호 관리수위는 기존 관리수위를 포함한 5개의 관리수위를 모의하였다. 각 시나리오에 따른 유입량, 호소수위 및 호소수질 변화를 모의하기위해 유역모형 HSPF와 호소모형인 EFDC-WASP 모형을 연계하여 활용하였다. 로버스트 의사결정 기법에 성능인자로는 신뢰도기반 이수, 치수, 수질지표를 활용하였으며, 결정인자으로 후회도를 활용하였다. 후회도는 로버스트의사 결정에서 널리 쓰이는 결정인자로 가장 좋은 성능인자와 그 대안의 성능인자의 차이를 의미한다. 최종적으로 최소의 최대 후회도를 갖는 시나리오를 1순위로 선정하였다.

• Journal of the korean academy of Pediatric Dentistry
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• v.45 no.4
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• pp.436-444
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• 2018

The purpose of this study was to compare the shear bond strengths of 3-in-1 flowable composite to the enamel and dentin of primary teeth to previous adhesive systems. 110 primary incisors were prepared and divided into two groups: Dentin group included 5 groups: 1) Scotch bond Multi-purpose plus(DSM), 2) Single-bond 2(DSB), 3) Clearfil SE bond(DSE), 4) All bond universal(DAB), 5) Constic(DC), and Enamel group included 6 groups: 1) Scotch bond Multi-purpose plus(ESM), 2) Single bond 2(ESB), 3) Clearfil SE bond(ESE), 4) All bond universal(EAB), 5) Constic(EC), 6) Constic with additional etching(ECE). A cylinder of composite was bonded to the prepared surface, and the shear bond strength was measured. In the dentin groups, group DC had significantly lower shear bond strength than group DSE. No significant difference was found between group DC, group DSM, group DSB and group DAB. In the enamel groups, there was no significant difference between group EC, group ESE, and group EAB. This material showed lowest shear bond strength among all tested materials in both enamel and dentin groups, showing insignificant difference with some adhesive systems. Therefore, 3-in-1 flowable composite can be used for primary teeth restoration but further studies are needed.

• Korean Journal of Agricultural and Forest Meteorology
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• v.17 no.2
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• pp.108-125
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• 2015

The agro-climatic index is one of the ways to assess the climate resources of particular agricultural areas on the prospect of agricultural production; it can be a key indicator of agricultural productivity by providing the basic information required for the implementation of different and various farming techniques and practicalities to estimate the growth and yield of crops from the climate resources such as air temperature, solar radiation, and precipitation. However, the agro-climate index can always be changed since the index is not the absolute. Recently, many studies which consider uncertainty of future climate change have been actively conducted using multi-model ensemble (MME) approach by developing and improving dynamic and statistical downscaling of Global Climate Model (GCM) output. In this study, the agro-climatic index of Korean Peninsula, such as growing degree day based on $5^{\circ}C$, plant period based on $5^{\circ}C$, crop period based on $10^{\circ}C$, and frost free day were calculated for assessment of the spatio-temporal variations and uncertainties of the indices according to climate change; the downscaled historical (1976-2005) and near future (2011-2040) RCP climate sceneries of AR5 were applied to the calculation of the index. The result showed four agro-climatic indices calculated by nine individual GCMs as well as MME agreed with agro-climatic indices which were calculated by the observed data. It was confirmed that MME, as well as each individual GCM emulated well on past climate in the four major Rivers of South Korea (Han, Nakdong, Geum, and Seumjin and Yeoungsan). However, spatial downscaling still needs further improvement since the agro-climatic indices of some individual GCMs showed different variations with the observed indices at the change of spatial distribution of the four Rivers. The four agro-climatic indices of the Korean Peninsula were expected to increase in nine individual GCMs and MME in future climate scenarios. The differences and uncertainties of the agro-climatic indices have not been reduced on the unlimited coupling of multi-model ensembles. Further research is still required although the differences started to improve when combining of three or four individual GCMs in the study. The agro-climatic indices which were derived and evaluated in the study will be the baseline for the assessment of agro-climatic abnormal indices and agro-productivity indices of the next research work.