• Structural Engineering and Mechanics
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• v.84 no.2
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• pp.181-206
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• 2022

This paper presents experimental modal analysis and static load testing results to validate the accuracy of dynamic parameters-based damage locating indices in RC structures. The study investigates the accuracy of different dynamic-based damage locating indices compared to observed crack patterns from static load tests and how different damage levels and scenarios impact them. The damage locating indices based on mode shape curvature and mode shape fourth derivate in their original forms were found to show anomalies along the beam length and at the supports. The modified forms of these indices show higher sensitivity in locating single and multi-cracks at different damage scenarios. The proposed stiffness reduction index shows good sensitivity in detecting single and multi-cracks. The proposed anomalies elimination procedure helps to remove the anomalies along the beam length. Also, the adoption of the proposed weighting method averaging procedure and normalization procedure help to draw the overall crack pattern based on the adopted set of modes.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.11
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• pp.1520-1527
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• 2013

The purpose of this study is to derive COE reduction targets of offshore wind power in Korea. In addition, innovation factors for achieving the COE reduction targets were derived. Also the COE reduction targets of offshore wind power was to improve that national policy, technology, industry and improving regulations would like to help. The results of this study has been created based on the various assumptions, scenarios and experts' discussions. Currently, offshore wind power generation price is 229.72won/kWh in 2012. According to the study, COE of offshore wind power has been proposed 88.8won/kWh at third scenario by 2030. This result has shown competitiveness with fossil fuel power generation.

• Journal of Environmental Impact Assessment
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• v.14 no.3
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• pp.117-126
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• 2005

This study was executed to know the best matrix of photochemical ozone reduction in the metropolitan area. For this object, we used the OZIPR(Ozone Isopleth Plotting Package for Research) model for comparing the effectiveness of VOCs and NOx amount variation about the ozone creation. Among the various ozone reduction scenarios, 50% reduction of VOCs from organic solvent and road traffic respectively was the best matrix for ozone reduction. Although it needs more accurate assessment and confirmation of VOCs and NOx emission amount data, according to existing data, the control of VOCs is the best way for photochemical ozone reduction in Seoul.

• Journal of Korean Society on Water Environment
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• v.29 no.1
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• pp.45-54
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• 2013

This study analyzes the reduction effects of runoff and flood damage through different arrangements of stormwater storage facilities. Three scenarios based on the spatial allocation of storage capacity are used: concentrated, decentralized and combinative. The characteristics of runoff and flood damage by scenario are compared. The XP-SWMM model is used for runoff simulation by the probable rainfall of return period. The result shows that the concentrated arrangement of storage facilities is most effective to reduce the amount of peak flow and to delay the time of peak flow. Yet, while the concentrated arrangement is most effective to reduce the inundation damage, it is not effective to reduce runoff volume. The decentralized arrangement is most effective to reduce runoff volume. The combinative arrangement is effective not only the runoff reduction but also the reduction of flood damage. The result indicates that the flood mitigation strategies against heavy rainfall need to consider decentralized on-site arrangement for the reduction of runoff volume along with concentrated off-site arrangement of storage facilities.

• Journal of Environmental Impact Assessment
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• v.17 no.4
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• pp.243-253
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• 2008

The purpose of this study was to simulate the reduction effect of soil loss in the Yongdam reservoir watershed using SWAT model. To evaluate accuracy for flow and sediment yield of SWAT model, calibration was performed for the period from Jan. 2002 to Dec. 2003, and the verification for Jan. 2005 to Dec. 2005. The calibration and the verification were carried out using data observed at the Cheoncheon gaging station. The $R^2$ and EI values in terms of a flow were 0.8 and 0.78 respectively for calibration, whereas they for verification were 0.88 and 0.86 respectively. In terms of a sediment yield, they were 0.7 and 0.48 respectively for calibration, whereas for verification were 0.64 and 0.54 respectively. As a results from model simulation, annual mean soil loss rates in terms of forest, paddy and upland were 0.02 ton/ha/yr, 0.15 ton/ha/yr and 7.58 ton/ha/yr, respectively. The results show that the land use type of a upland has more significant impact on a total soil loss as well as a sediment yield than other types of land use. The sediment delivery ratio was determined to be about 0.35. In this study 2 land cover change scenarios for upland area were considered. These scenarios were used an input to SWAT model in order to evaluate their impact on soil loss and sediment delivery. The results show that a reduction of the upland area would reduce the soil loss and sediment yield.

• Journal of Korean Society on Water Environment
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• v.34 no.3
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• pp.293-300
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• 2018

Ihe purpose of this study is to evaluate the effects the storage type of permeable concrete block paving (ST-PCBP) have on runoff reduction and infiltration increasement at Andong Maskdance Festival Square. This was accomplished using the NRCS-curve number method over the last 10 years. Two different scenarios were developed in this study for low impact development (LID) design. For the $1^{st}$ scenario, the walking path and parking lot were install using the ST-PCBP and runoff from the inline skating rink ($3,808m^2$) and lawn ($11,191m^2$) were routed to the ST-PCBP, but the rooftop runoff flowed into the storm water drainage system. For the $2^{nd}$ scenario, one of the non-structural BMPs, disconnected impervious surface (DIS), was applied so additional runoff from rooftop would enter the ST-PCBP. It was determined that ST-PCBP could significantly reduce surface runoff from the study area and increase infiltration with 71% and 88% of surface runoff reduction and 151% and 215% of infiltration increasement for scenarios 1 and 2, respectively. The effect of LID in the $2^{nd}$ scenario was better than the $1^{st}$ scenario, therefore DIS in conjunction with ST-PCBP could be a more cost-effective LID application.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.2
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• pp.224-232
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• 2018

According to government policy, renewable energy facility such as solar power generation is being implemented for newly constructed buildings. In recent years, the introduction of Energy Storage System (ESS) served as an emergency power for replacing an existing diesel generator has been increasing. Furthermore, in order to expand the efficacy of the ESS operation, operation in combination with renewable energy sources such as solar and wind power generation is increasing. Hence, development of the ESS operation algorithms for emergency mode as well as the peak power cut mode, which is the essential feature of ESS, are necessary. The operational scenarios of ESS need to consider load power requirement and the amount of the power generation by renewable energy sources. For the verification of the developed scenarios, tests under the actual situation are demanded, but there is a difficulty in simulating the emergency operation situation such as system failure in the actual site. Therefore, this paper proposes simulation models for the HILS(Hardware In the Loop Simulation) and operation modes developed through HILS for the ESS operated with renewable energy source under peak power reduction and emergency modes. The paper shows that the ESS operation scenarios developed through HILS work properly at the actual site, and it verifies the effectiveness of the control logic developed by the HILS.

• Journal of Climate Change Research
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• v.7 no.3
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• pp.257-268
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• 2016

Both economic growth and industrial structure have great influence on energy consumption and GHG emissions. This study analyzed long-term scenarios for GHG emissions projections considering economic growth and industry value added change. In consideration of 3 GDP and 3 industry value added outlook, total 9 scenarios were set; 'Assembly Industry Baseline(AI)', 'Assembly KEIT industry(AK)', 'Assembly Advanced Country industry(AA)', 'KDI Industry Baseline(KI)', 'KDI KEIT industry(KK)', 'KDI Advanced Country industry(KA)', 'OECD Industry Baseline(OI)', 'OECD KEIT industry(OK)', and 'OECD Advanced Country industry(OA)' scenarios. In consideration of the GDP increase rate and industry value added outlook, it is estimated that AI scenario's GHG emissions would be 777 million tons of $CO_2eq$ in 2030. On the other hand, in the case of OA scenario, GHG emissions would be 560.2 million tons of $CO_2eq$ in 2030. Differences between AI scenario's and OA scenario's were 216.8 million tons of $CO_2eq$. It can be identified by that GDP and industry value added change have great influence on GHG emissions. In view of the fact that Korea's amount of GHG emission reduction targets in 2030 were 218.6 million tons of $CO_2eq$ that the result of this research could give us valuable insight.

• Proceedings of the Korea Water Resources Association Conference
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• 2023.05a
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• pp.184-184
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• 2023

Globally, agriculture is one of the largest consumers and polluters of water resources, contributing to the unsustainable use of limited water resources. To reduce the resource use and environmental footprints associated with current and future food systems, researchers and policy makers have recommended the transition to sustainable and healthier diets and the reduction of food loss and waste along the food supply chain. However, there is limited information on the synergistic effects and trade-offs of adopting the two measures. In this study, we assessed the water-saving potential of the two measures in South Korea using environmentally extended input-output relying on the EXIOBASE database for the reference year 2020, along with scenario analysis to model the potential outcomes. Specifically, we analyzed scenarios where meat consumption was reduced by 30% and 50% and in combination with a 50% reduction in food waste at the consumption stage for each scenario. According to our findings, by considering individual measures of dietary change and food waste reduction, shifting to a diet with 30% and 50% less meat consumption could lead to reduction in water footprint by 6.9% and 7.5%, respectively, while 50% reduction in food waste at the consumption stage could save about 14% of water footprint. However, the synergistic effects of the two measures such as 30% less meat consumption and 50% food waste reduction, and 50% less meat consumption and 50% food waste reduction result to 20% and 24% reductions in water footprint, respectively. Moreover, our findings also showed that increasing food consumption with high environmental impacts could promote resources use inefficiency when waste occurs. Thus, policy strategies that address synergistic effects of both dietary change and food waste reduction should be strengthened to achieve sustainable food system. International and national policies can increase resource efficiency by utilizing all available reduction potentials while considering strategies interactions.

• Journal of Environmental Science International
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• v.11 no.10
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• pp.1125-1131
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• 2002

This study was performed to plan pollutant loading allocation by sub-watershed at Kumho river basin located in the north Kyeongsang province. HEC-geoHMS which is extension program of ArcView was used to extract sub-watershed. To simulate water quality, Qua12eu model was calibrated and validated. BOD was simulated under several scenarios to evaluate reduction effects of pollutant loading. Uniform treatment and transfer matrix method was considered. Effects of headwater flow rate and efficiency waste water treatment plant were also considered.