• Journal of The Korean Society of Agricultural Engineers
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• v.63 no.5
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• pp.1-11
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• 2021

Soil moisture plays a critical role in hydrological processes, land-atmosphere interactions and climate variability. It can limit vegetation growth as well as infiltration of rainfall and therefore very important for agriculture sector and food protection. Recently, due to the increased damage from drought caused by climate change, there is a frequent occurrence of shortage of agricultural water, making it difficult to supply and manage stable agricultural water. Efficient water management is necessary to reduce drought damage, and soil moisture management is important in case of upland crops. In this study, soil moisture was calculated based on the water balance model, and the suitability of soil moisture data was verified through the application. The regional soil moisture was calculated based on the meteorological data collected by the meteorological station, and applied the Runs theory. We analyzed the spatiotemporal variability of soil moisture and drought impacts, and analyzed the correlation between actual drought impacts and drought damage through correlation analysis of Standardized Precipitation Index (SPI). The soil moisture steadily decreased and increased until the rainy season, while the drought size steadily increased and decreased until the rainy season. The regional magnitude of the drought was large in Gyeonggi-do and Gyeongsang-do, and in winter, severe drought occurred in areas of Gangwon-do. As a result of comparative analysis with actual drought events, it was confirmed that there is a high correlation with SPI by each time scale drought events with a correlation coefficient.

• Journal of Climate Change Research
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• v.34 no.22
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• pp.9093-9113
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• 2021

This study examines the role of the relative wind (RW) effect (wind relative to ocean current) in the regional ocean circulation and extratropical storm track in the south Indian Ocean. Comparison of two high-resolution regional coupled model simulations with and without the RW effect reveals that the most conspicuous ocean circulation response is the significant weakening of the overly energetic anticyclonic standing eddy off Port Elizabeth, South Africa, a biased feature ascribed to upstream retroflection of the Agulhas Current (AC). This opens a pathway through which the AC transports the warm and salty water mass from the subtropics, yielding marked increases in sea surface temperature (SST), upward turbulent heat flux (THF), and meridional SST gradient in the Agulhas retroflection region. These thermodynamic and dynamic changes are accompanied by the robust strengthening of the local low-tropospheric baroclinicity and the baroclinic wave activity in the atmosphere. Examination of the composite life cycle of synoptic-scale storms subjected to the high-THF events indicates a robust strengthening of the extratropical storms far downstream. Energetics calculations for the atmosphere suggest that the baroclinic energy conversion from the basic flow is the chief source of increased eddy available potential energy, which is subsequently converted to eddy kinetic energy, providing for the growth of transient baroclinic waves. Overall, the results suggest that the mechanical and thermal air-sea interactions are inherently and inextricably linked together to substantially influence the extratropical storm tracks in the south Indian Ocean.

• Journal of Wetlands Research
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• v.21 no.spc
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• pp.149-156
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• 2019

Assessing the hydrological safety of existing dams against climate change and providing appropriate adaptation measures are important in terms of sustainable water supply and management. Korean major dams ensure their safety through periodic inspections and maintenance according to 'Special Act on the safety control and maintenance of establishments'. Especially when performing a full safety examination, principal engineer must assess the hydrological safety and prepare for potential risks. This study employed future probable maximum precipitation (PMP) estimated using outputs of regional climate models based on RCP4.5 and RCP8.5 greenhouse-gas emission scenarios to assess climate change impact on existing dam's future hydrological safety. The analysis period was selected from 2011 to 2040, from 2041 to 2070, and from 2071 to 2100. Evaluating the potential risk based on the future probable maximum flood (PMF) for four major dams (A, B, C, I) showed that climate change could induce increasing the overflow risk on three dams (A, B, I), although there are small differences depending on the RCP scenarios and the analysis periods. Our results suggested that dam managers should consider both non-structural measures and structural measures to adapt to the expected climate change.

• Atmosphere
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• v.29 no.5
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• pp.511-523
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• 2019

A new Korean Meteorological Administration (KMA) airborne measurement platform has been established for regular observations for scientific purpose over South Korea since late 2017. CRDS G-2401m analyzer mounted on the King Air 350HW was used to continuous measurement of CO₂, CH₄ and CO mole fraction. The total uncertainty of measurements was estimated to be 0.07 ppm for CO₂, 0.5 ppb for CH₄, and 4.2 ppb for CO by combination of instrument precision, repeatability test simulated in-flight condition and water vapor correction uncertainty. The airborne vertical profile measurements were performed at a regional Global Atmosphere Watch (GAW) Anmyeon-do (AMY) station that belongs to the Total Carbon Column Observing Network (TCCON) and provides concurrent observations to the Greenhouse Gases Observing Satellite (GOSAT) overpasses. The vertical profile of CO₂ shows clear altitude gradient, while the CH₄ shows non-homogenous pattern in the free troposphere over Anmyeon-do. Vertically averaged CO₂ at the altitude between 1.5 and 8.0km are lower than AMY surface background value about 7 ppm but higher than that observed in free troposphere of western pacific region about 4 ppm, respectively. CH₄ shows lower level than those from ground GAW stations, comparable with flask airborne data that was taken in the western pacific region. Furthermore, this study shows that the combination of CH₄ distribution in free troposphere and trajectory analysis, taking account of convective mixing, is a useful tool in investigating CH₄ transport processes from tropical region to Korean region in winter season.

• Journal of The Korean Society of Agricultural Engineers
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• v.59 no.4
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• pp.53-64
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• 2017

The equations and emission factors for estimating national GHGs are developed based on IPCC guidelines. The GHGs on livestock sector has been calculated using methodologies following 1996 IPCC guideline in South Korea although 2006 IPCC guideline was announced in 2006. The purpose of this study is to understand the implications of guideline updates for national GHGs changes in the livestock sector and analyze the effect of regional major livestock characteristics using KOSTAT time series data (1990 ~ 2014). The results show a new guideline makes GHGs reduce in the livestock sector up to 11 % with subdivided emission factors and the livestock characteristics affect regional GHGs. Gyeonggi-do, the top emitter among 16 states, records 784 thousand tons $CO_2eq.$ and Daejeon has the highest potential (82 %) of GHGs reduction. Swine is the most contributor for regional GHGs except Seoul and Gwangju, but the share of GHGs for chickens is less than 12 % in spite of the largest livestock population (87 %).

• Journal of the Korean Geographical Society
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• v.50 no.1
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• pp.91-103
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• 2015

The purpose of this study is to investigate if there is any regional distribution difference in the frequency of geographical location's name mentioned on the SAT Korean geography test. The reviewed items were used for geography subject test in Korean SAT exam in between 2005 and 2015. Researchers analyzed how often a location had been mentioned in the form of maps, captions, and graphs in the national college entrance exam for 11 years. The result indicated that 42% out of the 220 items were using map and about 33% of them represented a specific region. Especially, items related with climate, industries, and local area section contained a specific area information more frequently than others. Moreover, there were 76 cities mentioned in geography subject test on Korean SAT exam during 11 years and 25 places among them were referred to more than three times. The most frequently appeared city was Seoul followed by Incheon, Daegu, Busan, Gangneung, and Jeju and this result shows that there were some regional bias in geography test on the SAT Korean exam.

• Journal of the Society of Disaster Information
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• v.13 no.2
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• pp.199-212
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• 2017

Rapid roadway snow removal is significantly important due to difficult occurrence estimation of heavy snowfall disasters by global warming and climate change. Local governments of S. Korea have snow removal equipments and vehicles based on past experiences without considering snowfall and roadway characteristics. The objective of this research is to develop the demand estimation procedure for snow removal equipments and vehicles based on regional snowfall and roadway characteristics. This research first classifies regional snowfall characteristics using KMO's ten-year snowfall data. Second, roadway snow removal length is computed for local governments. Real possession data is compared with demand estimation of snow removal equipments & vehicles for each local government with roadway snow removal scenarios. Finally, required demands of snow removal equipments & vehicles are predicted by concerning regional snowfall amount and required snow removal hours. Results from this research are used for developing heavy snowfall disaster management policies for optimal demands and snow removal routes of 229 local governments.

• Journal of the Korean Geosynthetics Society
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• v.17 no.4
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• pp.157-168
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• 2018

Recently, the occurrence of typhoons and heavy rainfall is increasing due to climate change. This causes increase in possibility of landslide damages in rural areas. However, in reality, the precise engineering stability assessment studies are still insufficient. Therefore, in order to reduce the landslide damages and effectively manage mountainous areas, the development of disaster prevention techniques is needed. In this study, to analyze the shock absorbing effect of the buffer-spring during application of dynamic impact load in the debris flow protection system, numerical analysis is carried out for each free field of the buffer-spring and the load sharing ratio of the buffer-spring is also examined. In addition, the field applicability is verified by comparison of the tensile strength of the conventional buffer-spring and the wedge type buffer-spring on various magnitudes of dynamic impact load. As a result of the study, it is found that the net-type debris protection system is effective to mitigate loss of properties and human lifes during landslide.

• Journal of Korea Society of Waste Management
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• v.35 no.8
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• pp.777-784
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• 2018

Since climate change increases the risk of extreme rainfall events, concerns on flood management have also increased. In order to rapidly recover from flood damages and prevent secondary damages, fast collection and treatment of flood debris are necessary. Therefore, a quick and precise estimation of flood debris generation is a crucial procedure in disaster management. Despite the importance of debris estimation, methodologies have not been well established. Given the intrinsic heterogeneity of flood debris from local conditions, a regional-scale model can increase the accuracy of the estimation. The objectives of this study are 1) to identify significant damage variables to predict the flood debris generation, 2) to ascertain the difference in the coefficients, and 3) to evaluate the accuracy of the debris estimation model. The scope of this work is flood events in Ulsan city region during 2008-2016. According to the correlation test and multicollinearity test, the number of damaged buildings, area of damaged cropland, and length of damaged roads were derived as significant parameters. Key parameters seems to be strongly dependent on regional conditions and not only selected parameters but also coefficients in this study were different from those in previous studies. The debris estimation in this study has better accuracy than previous models in nationwide scale. It can be said that the development of a regional-scale flood debris estimation model will enhance the accuracy of the prediction.

• Journal of Science and Technology Studies
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• v.19 no.3
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• pp.291-333
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• 2019

The regional innovation policies so far have been separated from the social problems facing the local communities. The regional innovation policies, regarding the region as the location of the business, have focused on the invigoration of business innovation activities. However, as the recent emergence of the new paradigm of innovation policy aiming the sustainability, 'transformative innovation policy,' has led to a search for regional innovation policies that begin with solving the local social problems. This research paper deals with regional innovation theory that starts from searching for solutions and system transformation for social problems such as climate crisis and energy problems. The objective is to present a new framework called 'transformative regional innovation policy' and to improve its content through case studies by combining the results of the transformative innovation policy and the regional innovation policy studies. In particular, the contribution of this paper is to analyze and discuss the concept of the transition platform, which aims to solve the local social problems, through the case studies of Gussing, Austria and Esbjerg, Denmark. Lastly, it discusses the derived implications of the cases applied in Korean society.