• Journal of Multimedia Information System
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• v.5 no.4
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• pp.235-244
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• 2018

Potential maximum soil moisture retention (S) is a dominant parameter in the Soil Conservation Service (SCS; now called the USDA Natural Resources Conservation Service (NRCS)) runoff Curve Number (CN) method commonly used in hydrologic modeling for event-based flood forecasting (SCS, 1985). Physically, S represents the depth [L] soil could store water through infiltration. The depth of soil moisture retention will vary depending on infiltration from previous rainfall events; an adjustment is usually made using a factor for Antecedent Moisture Conditions (AMCs). Application of the method for continuous simulation of multiple storms has typically involved updating the AMC and S. However, these studies have focused on a time step where S is allowed to vary at daily or longer time scales. While useful for hydrologic events that span multiple days, this temporal resolution is too coarse for short-term applications such as flash flood events. In this study, an approach for deriving a time-variable potential maximum soil moisture retention curve (S-curve) at hourly time-scales is presented. The methodology is applied to the Napa River basin, California. Rainfall events from 2011 to 2012 are used for estimating the event-based S. As a result, we derive an S-curve which is classified into three sections depending on the recovery rate of S for soil moisture conditions ranging from 1) dry, 2) transitional from dry to wet, and 3) wet. The first section is described as gradually increasing recovering S (0.97 mm/hr or 23.28 mm/day), the second section is described as steeply recovering S (2.11 mm/hr or 50.64 mm/day) and the third section is described as gradually decreasing recovery (0.34 mm/hr or 8.16 mm/day). Using the S-curve, we can estimate the hourly change of soil moisture content according to the time duration after rainfall cessation, which is then used to estimate direct runoff for a continuous simulation for flood forecasting.

• Journal of Wetlands Research
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• v.21 no.3
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• pp.191-198
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• 2019

High impervious surfaces increase the surface runoff during rainfall and reduces the underground infiltration thereby leading to water cycle distortion. The distortion of water cycle causes various urban environmental problems such as urban flooding, drought, water pollutant due to non-point pollution runoff, and water ecosystem damage. Climate change intensified seasonal biases in urban rainfall and affected urban microclimate, thereby increasing the intensity and frequency of urban floods and droughts. Low impact development(LID) technology has been applied to various purposes as a technique to reduce urban environmental problems caused by water by restoring the natural water cycle in the city. This study evaluated the contribution of hydrologic characteristics and water cycle recovery after LID application using long-term monitoring results of various LID technology applied in urban areas. Based on the results, the high retention and infiltration rate of the LID facility was found to contribute significantly to peak flow reduction and runoff delay during rainfall. The average runoff reduction effect was more than 60% at the LID facility. The surface area of the LID facility area ratio(SA/CA) was evaluated as an important factor affecting peak flow reduction and runoff delay effect.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.24 no.3
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• pp.400-421
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• 2019

This study was conducted to find out the seasonal distribution characteristics of meiobenthic communities to understand the benthic ecosystem of Gwangyang Bay, one of the representative bays in the southern coast of Korea. The faunal sampling was conducted eight times seasonally at 20 stations from 2010 to 2011. Among the meiobenthic fauna that appeared during the study period, the nematodes and harpacticoids were the most dominant. In the summer of 2011, the lowest density ($13ind.10m^{-2}$) was seen at station 10 on the inner part of the bay. In the winter of 2011, the highest density ($3,109ind.10m^{-2}$) was seen at station 4 on the inner part of the bay. Although the trend of seasonal changes in density was not clear, the meiobenthic community was seen to be affected more by the environmental factors in each season. Particularly, while the density of the harpacticoids, a dominant faunal group, showed negative correlations with the organic content and average particle size in the summer sediments (p<0.05, p<0.01), the density of the nematodes showed no significant correlation with the environmental factors except with the winter average particle size and the bottom layer's water temperature. The density change of meiobenthos showed irregular changes in Gwangyang Bay, instead of a general trend showing a low density in winter due to low water temperature but an increased density in spring and summer when the water temperature rises and a decreased one again in fall. Considering such a seasonal trend, it seems that the benthic ecosystem of Gwangyang Bay is affected more by artificial environmental factors than by natural environmental ones.

• Journal of Korea Water Resources Association
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• v.52 no.4
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• pp.301-312
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• 2019

The importance of the dual drainage system model has increased as the urban flood damage has increased due to the increase of local storm due to climate change. The dual drainage model is a model for more accurately expressing the phenomena of surface flow and conduit flow. Surface runoff and pipe runoff are analyzed through the respective equations and parameters. And the results are expressed visually in various ways. Therefore, inundation analysis results of dual drainage model are used as important data for urban flood prevention plan. In this study, the applicability of the COBRA model, which can be interpreted by combining the dual drainage system with the natural watershed and the urban watershed, was investigated. And the results were compared with other dual drainage models (XP-SWMM, UFAM) to determine suitability of the results. For the same watershed, the XP-SWMM simulates the flooding characteristics of 3 types of dual drainage system model and the internal flooding characteristics due to the lack of capacity of the conduit. UFAM showed the lowest inundation analysis results compared with the other models according to characteristics of consideration of street inlet. COBRA showed the general result that the flooded area and the maximum flooding depth are proportional to the increase in rainfall. It is considered that the COBRA model is good in terms of the stability of the model considering the characteristics of the model to simulate the effective rainfall according to the soil conditions and the realistic appearance of the flooding due to the surface reservoir.

• Journal of the Korean Association of Geographic Information Studies
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• v.21 no.4
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• pp.91-107
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• 2018

It is required to monitor and assess the desertification in Tunisia, where the Sahara Desert, which is located in the southern part of Tunisia, is recently expanding northward. In this study, by using remote sensed data, land cover changes were examined, and the Normalized Difference Vegetation Index (NDVI), Topsoil Grain Size Index (TGSI) and Albedo are used to monitor and assess desertification in Tunisia. Decision Tree was constructed, and the frequencies and trends of each assessment indicator, desertification degree and land cover were identified. In addition, we analyzed the correlation between assessment indicators and precipitation. As a result, desertification is generally intensifying northward, especially in areas with high levels of desertification. Also, bivariate correlation analysis showed that Albedo, NDVI and TGSI were all highly correlated with precipitation. It indicates that changes in precipitation have also been shown to affect Tunisian desertification. In conclusion, this study has improved the usability of various methodologies considering the assessment indicators based on satellite imagery, Decision Tree, which is a method of evaluating them complexly, and trends of land cover change.

• Journal of Korean Society of Forest Science
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• v.108 no.3
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• pp.418-428
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• 2019

The purpose of this study was to analyze and clarify the forest information shown in the Korean Peninsula Forest Distribution Map (KPFDM) printed in 1910. First, the background, process, results, and reliability of the Forest Survey Project (1910), which is the basis of the KPFDM, were evaluated. Next, the information of the KPFDM, preserved as a paper map, was digitized to show forest status and forest type. The results of the analysis can be summarized as follows: Analyzing the Korean peninsula of the 1910 period in terms of the present South and North Korean regions, stocked forests were found to be more widely distributed (73%) in the northern region. The southern region largely consisted of deforested areas, with young-growth trees and unstocked forests making up 80% of all forests there. The northern region had abundant natural forests, with 80% of the forests in Yanggang-do, which currently includes Mt. Baekdu and the Hyesan area, composed of stocked forests. Pinus densiflora was found about 2.7 times more often in the southern region than in the northern region. Large numbers of coniferous trees excluding Pinus densiflora were found in the northern region. In particular, 53% of the forests and 72% of the stocking land in the southern region were composed of Pinus densiflora.

• Korean Journal of Remote Sensing
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• v.35 no.3
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• pp.483-489
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• 2019

True color images display colors similar to natural colors. This has the advantage that it is possible to monitor rapidly the complex earth atmosphere phenomenon and the change of the surface type. Currently, various organizations are producing true color images. In Korea, it is necessary to produce true color images by replacing generations with next generation weather satellites. Therefore, in this study, visual enhancement for true color image production was performed using Top of Atmosphere (TOA) data of Advanced Himawari Imager (AHI) sensor mounted on Himawari-8 satellite. In order to improve the visualization, we performed two methods of Nonlinear enhancement and Histogram equalization. As a result, Histogram equalization showed a strong bluish image in the region over $70^{\circ}$ Solar Zenith Angle (SZA) compared to the Nonlinear enhancement and nonlinear enhancement technique showed a reddish vegetation area.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.6
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• pp.201-209
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• 2019

This study aimed to find out the morphological evolution process for future vision of world smart city. The contents and methods of study was divided and compared by 4 continents and Korea focused on the convergence numbers of ET and IT in smart city and did correlation analysis and analysis of convergence number in device/technology by periods. The analysis materials were 32 cases of smart city in whole world and times were 4 periods. The results of study were listed below. First, the smart city in period 1 was morphological evolutions preserved environment and kept natural form of existing city and filled up device/technology. Second, the smart city in period 2 was morphological evolutions through ET-centric development. Third, the smart city in period 3 was morphological evolutions through advancement of ET and device/technology related to production of energy. Forth, the smart city in period 4 was morphological evolutions fusing, dissipating and creating new ET and IT through the advancement process of all technologies. In conclusion, morphological evolution of smart city will change systematic city structure of convergence form, not each discriminating development between ET and IT, and the forming of smart city will be evolved by repetitive convergence process of technologies continually.

• Journal of the Korea Convergence Society
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• v.12 no.4
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• pp.311-316
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• 2021

The college's beauty department, which has a globalized education system that breaks away from the uniform beauty concept, can dominate in the fierce competition with other schools, and the development and vitalization of the department is guaranteed. In addition, research on the department name is very necessary to establish internal and external PR strategies for affiliated departments and departments and to analyze the direction of realistic beauty education. Accordingly, as a result of analyzing the trends of the department and department name by classifying the universities in Yeonghonam into four regions, the departments belonging to each region of the beauty department showed the most belonging to the natural science and arts and sports departments. In addition, the names of beauty departments by region are Busan and Gyeongnam, Daegu and Gyeongbuk, Gwangju and Jeonnam, and Jeonbuk with 5 beauty departments (29.41%), 3 beauty design schools (13.04%), and 8 beauty and beauty departments. (50.00%), beauty design departments, 2 schools (33.33%). This study makes it possible to cultivate professional beauticians who cultivate an artistic and creative sense that meets the educational goals of beauty education, and it is expected that it will be provided as a very necessary basic data for the division of departments or change of department name according to detailed majors.

• Journal of Digital Convergence
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• v.19 no.8
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• pp.235-240
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• 2021

Currently, the number of visitors to Oreum is increasing and the trend of tourism is changing rapidly. The motivation for visiting Oreum is also changing from relaxation and pleasure to experiences. In line with this change, people visit the mountain by selecting motivation such as marriage and family photos, not just exercise. However, it is difficult to search for an Oreum that matches the tourists' motivation. In order to solve these problems, we proposed a system that provides the association between Oreum and concept based on the number of search results from web search engines in real time. User can select the desired date to check the associations for past or selected periods and concepts. Through this research, visitors to Oreum, Jeju's natural heritage, can contribute to the development of tourism in Jeju. In the future, the concept of visiting beaches or seas, not just Jeju Oreum, can be provided. In this work, search results from websites are collected, stored in a database, and search results of Oreum and concept are provided on the homepage to classify Oreum trends.