• Korean Journal of Agricultural and Forest Meteorology
• /
• v.23 no.3
• /
• pp.156-162
• /
• 2021

The number of smart farms has increased to save labor in agricultural production as the subsidy become available from central and local governments. The number of illegal greenhouses has also increased, which causes serious issues for the local governments. In the present study, we developed Mask-RCNN model to detect greenhouses based on satellite images. Greenhouses in the satellite images were labeled for training and validation of the model. The Mask-RC NN model had the average precision (AP) of 75.6%. The average precision values for 50% and 75% of overlapping area were 91.1% and 81.8%, respectively. This results indicated that the Mask-RC NN model would be useful to detect the greenhouses recently built without proper permission using a periodical screening procedure based on satellite images. Furthermore, the model can be connected with GIS to establish unified management system for greenhouses. It can also be applied to the statistical analysis of the number and total area of greenhouses.

• Journal of Korea Water Resources Association
• /
• v.55 no.3
• /
• pp.245-255
• /
• 2022

Evaluating the qualitative the qualitative process of water resources by using various indicators, as one of the most prevalent methods for optimal managing of water bodies, is necessary for having one regular plan for protection of water quality. In this study, zoning maps were developed on a yearly basis by collecting and reviewing the process, validating, and performing statistical tests on qualitative parameters҆ data of the Iranian aquifers from 1995 to 2020 using Geographic Information System (GIS), and based on Inverse Distance Weighting (IDW), Radial Basic Function (RBF), and Global Polynomial Interpolation (GPI) methods and Kriging and Co-Kriging techniques in three types including simple, ordinary, and universal. Then, minimum uncertainty and zoning error in addition to proximity for ASE and RMSE amount, was selected as the optimum model. Afterwards, the selected model was zoned by using Scholar and Wilcox. General evaluation of groundwater situation of Iran, revealed that 59.70 and 39.86% of the resources are classified into the class of unsuitable for agricultural and drinking purposes, respectively indicating the crisis of groundwater quality in Iran. Finally, for validating the extracted results, spatial changes in water quality were evaluated using the Groundwater Quality Index (GWQI), indicating high sensitivity of aquifers to small quantitative changes in water level in addition to severe shortage of groundwater reserves in Iran.

• Journal of the Korean Geotechnical Society
• /
• v.38 no.4
• /
• pp.59-70
• /
• 2022

There is a growing interest in evaluating earthquake damage and determining disaster prevention measures due to the magnitude 5.8 earthquake in Pohang, Korea. Since the liquefaction phenomena occurred extensively in the residential area as a result of the earthquake, there was a demand for research on liquefaction phenomenon evaluation and liquefaction disaster prediction. Liquefaction is defined as a phenomenon where the strength of the ground is completely lost due to a sudden increase in excess pore water pressure caused due to large dynamic stress, such as an earthquake, acting on loose sand particles in a short period of time. The liquefaction potential index, which can identify the occurrence of liquefaction and predict the risk of liquefaction in a targeted area, can be used to create a liquefaction hazard map. However, since liquefaction assessment using existing field testing is predicated on a single borehole liquefaction assessment, there has been a representative issue for the whole targeted area. Spatial interpolation and geographic information systems can help to solve this issue to some extent. Therefore, in order to solve the representative problem of geotechnical information, this research uses the kriging method, one of the geostatistical spatial interpolation techniques, and constructs a geotechnical information database for liquefaction and spatial interpolation. Additionally, the liquefaction hazard map was created for each return period using the constructed geotechnical information database. Cross validation was used to confirm the accuracy of this liquefaction hazard map.

• Journal of the Korean Society of Earth Science Education
• /
• v.15 no.1
• /
• pp.27-46
• /
• 2022

The purpose of this study was to examine the perceptions of novelty space among pre-service elementary and secondary earth science teachers. We conducted a survey to explore the perceptions of 38 pre-service elementary school teachers at the National University of Education and 31 pre-service secondary earth science teachers at the Department of Earth Science Education at B University. Semi-structured interviews were conducted with 12 participants, including three pre-service elementary teachers and nine pre-service secondary science teachers. In addition to the elements of novelty space, prior knowledge (cognition), prior outdoor learning experience (psychology), familiarity (geography) with outdoor field learning, and social and technical elements were added. When classified based on elementary and secondary levels, there were statistically significant differences in cognitive, psychological, geographic, and social areas for the elements of novelty space. Statistical differences indicated that the experience or capital related to outdoor learning may have resulted from more pre-service secondary earth science teachers than pre-service elementary teachers. In additional interviews, both elementary and secondary pre-service teachers reported that competencies in the technical domain would be emphasized in the future owing to the necessity and the technical development of virtual-reality-based outdoor field learning programs. This study emphasizes the academic significance of novelty space that should be considered to conduct geological field learning for elementary and secondary earth science pre-service teachers while considering the current post-pandemic educational context.

• Journal of the Economic Geographical Society of Korea
• /
• v.26 no.3
• /
• pp.289-309
• /
• 2023

While South Korea's universal healthcare system has garnered attention in public health, the issue of inequality in healthcare service provision among different age groups has incessantly become a significant concern. The focus of this concern is primarily on essential healthcare services, encompassing fundamental aspects of healthcare such as internal medicine, family medicine, and pediatric and adolescent care. This inequality is not limited to differences among age groups (both junior and senior demographics) but also extends to potential disparities in healthcare services based on geographic location, particularly in urban and rural contexts. This paper aims to investigate disparities in primary healthcare service resources in South Korea's evolving economic landscape between 1995 and 2021. We utilize a set of inequality indices with a spatial perspective through geographic cluster analysis. The findings reveal that concerns about inequality have been amplified during various economic events, including the IMF crisis in 1999, the global financial crisis in 2008, and the COVID-19 pandemic in 2020. These years are identified as significant phases that have contributed to manifesting spatial disparities in primary healthcare provisions, with a particular emphasis on the senior-aged population rather than junior or all population groups. Our findings underscore the pressing need to address the unequal distribution of essential healthcare resources as part of preparedness for potential economic impacts, requiring a comprehensive consideration of the interconnected nature of demographic and spatial dimensions in healthcare services.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.18 no.6
• /
• pp.1143-1150
• /
• 2023

The global climate crisis and the implementation of low-carbon policies have led to a growing interest in renewable energy and a growing number of related industries. Among them, solar power is attracting attention as a representative eco-friendly energy that does not deplete and does not emit pollutants or greenhouse gases. As a result, the supplement of solar power facility is increasing all over the world. However, solar power is easily affected by the environment such as geography and weather, so accurate solar power forecast is important for stable operation and efficient management. However, it is very hard to predict the exact amount of solar power using statistical methods. In addition, the conventional prediction methods have focused on only short- or long-term prediction, which causes to take long time to obtain various prediction models with different prediction horizons. Therefore, this study utilizes a many-to-many structure of a recurrent neural network (RNN) to integrate short-term and long-term predictions of solar power generation. We compare various RNN-based very short- and long-term prediction methods for solar power in terms of MSE and R² values.

• Economic and Environmental Geology
• /
• v.44 no.2
• /
• pp.135-152
• /
• 2011

Nitrate concentrations in springs at the southern slope of Jeju Island were predicted using multiple linear regression (MLR) of spatial variables including hydrogeological parameters and land use characteristics. Springs showed wide range of nitrate concentrations from <0.02 to 86 mg/L with a mean of 20 mg/L. Spatial variables were generated for the circular buffer when the optimal buffer radius was assigned as 400 m. Selected regression models were tested using the p values and Durbin-Watson statistics. Explanatory variables were selected using the adjusted $R^2$, Cp (total squared error) and AIC (Akaike's Information Criterion), and significance. In addition, mutual linear relations between variables were also considered. Small portion of springs, usually <10% of total samples, were identified as outliers indicating limitations of MLR using circular buffers. Adjusted $R^2$ of the proposed models was improved from 0.75 to 0.87 when outliers were eliminated. In particular, the areal proportion of natural area had the greatest influence on the nitrate concentrations in springs. Among anthropogenic land uses, the influence of nitrate contamination is diminishing in the following order of orchard, residential area, and dry farmland. It is apparent quality of springs in the study area is likely to be controlled by land uses instead of hydrogeological parameters. Most of all, it is worth highlighting that the contamination susceptibility of springs is highly sensitive to nearby land uses, in particular, orchard.

• Journal of the Korean Geographical Society
• /
• v.42 no.4
• /
• pp.488-505
• /
• 2007

The purposes of this research are twofold; 1) to verify spatial differences of tectonic movement using the spatial distribution of earthquakes, and 2) to infer mechanisms that generate spatial accumulation patterns of earthquakes in the Korean Peninsula. The first part of this sequential paper (Park, 2007) argues that the Korean Peninsula consists of four geostructural regions in which tectonic deformation and consequent geomorphological development patterns are different from each other Since this conclusion has been made by terrain analyses alone, it is necessary to verify this suggestion using other independent geophysical data. Because earthquakes are results of movement and deformation of land masses moving in different directions, the distribution of earthquake epicenters may be used to identify the direction and rates of land mass movement. This paper first analysed the spatial distribution of earthquakes using spatial statistics, and then results were compared with the spatial arrangement of geostructural regions. The spatial distribution of earthquakes in the Korean Peninsula can be summarized as the followings; firstly, the intensity of earthquakes shows only weak spatial dependency, and shows large difference even at adjacent regions. Secondly, the epicenter distribution has a clear spatial accumulation pattern, even though the intensity of earthquake shows a random pattern. Thirdly, the high density area of earthquakes shows a clear 'L' shape, passing through Pyeongannam-do, centered at Pyeongyang, and Hwanghae-do, Seosan and Pohang. The correlation coefficient between the density of earthquakes and distance from geostructral region boundaries is much higher than those between the density of fault lines and distance from tectonic division boundaries. Since fault lines and tectonic divisions in the Korean Peninsula are the results of long-term geological development, there is an apparent scale discrepancy to find significant correlations with earthquakes. This result verifies the research hypothesis that the Korean Peninsula is divided into four geostructral regions in which each has its own moving direction and spatial deformation characteristics. The existence of geostructural regions is also supported by the movement parrerns of land masses estimated from the GPS measurements. This conclusion is expected to provide a new perspective to understand the geomorphological developments and the earthquake occurrences in the Korean Peninsula.

• Journal of the Economic Geographical Society of Korea
• /
• v.9 no.1
• /
• pp.23-38
• /
• 2006

This study attempts to investigate the spatial characteristics of cultural economies of Bukchon in Seoul, where abundant cultural assets exist. This area has been the administrative-political core locale since 14C, therefore, a lot of traditional- and contemporary-cultural facilities are remains, This area possessed unique place characteristics by coexisting traditional and modern cultures, and thus attracted to culture demanders. Recently many economic activities have increased in this area, and most of them are related with the cultural elements of the region, In particular creative retail shops, which produce goods by flexible-specialized production system, have been agglomerated in this area, The goods are designed, produced, and sold at the shop place. Most of them are uniquely designed hand made products, and produced a few amount. The economic value of these products related with the cultural environment of Bukchon. These creative shops emerged at the front of Samcheongdong street in the beginning, and then have diffused into the inside of Samcheongdong street and Hwagae street. The shops have very unique exteriors related with traditional houses in this area, and located on roadsides where are not many passerby. Most owners of the retail stores are highly educated and studied design, and produce goods by themselves at the shops. The reason that they opened their shops in Bukchon is directly related with the unique cultural environment of this area. They hope that more unique and artistic stores join this area so that developed this area as culture and fashion combined area.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.18 no.2
• /
• pp.174-189
• /
• 2015

The objective of this study was to reconstruct spatial information using the results of the investigation and evaluation of the health of the living organisms, habitat, and water quality at the investigation points for the aquatic ecosystem health of the Nakdong River basin, to support the rational decision making of the aquatic ecosystem preservation and restoration policies of the Nakdong River basin using spatial analysis techniques, and to present efficient management methods. To analyze the aquatic ecosystem health of the Nakdong River basin, punctiform data were constructed based on the position information of each point with the aquatic ecosystem health investigation and evaluation results of 250 investigation sections. To apply the spatial analysis technique, the data need to be reconstructed into areal data. For this purpose, spatial influence and trends were analyzed using the Kriging interpolation(ArcGIS 10.1, Geostatistical Analysis), and were reconstructed into areal data. To analyze the spatial distribution characteristics of the Nakdong River basin health based on these analytical results, hotspot(Getis-Ord Gi, $G^*_i$), LISA(Local Indicator of Spatial Association), and standard deviational ellipse analyses were used. The hotspot analysis results showed that the hotspot basins of the biotic indices(TDI, BMI, FAI) were the Andong Dam upstream, Wangpicheon, and the Imha Dam basin, and that the health grades of their biotic indices were good. The coldspot basins were Nakdong River Namhae, the Nakdong River mouth, and the Suyeong River basin. The LISA analysis results showed that the exceptional areas were Gahwacheon, the Hapcheon Dam, and the Yeong River upstream basin. These areas had high bio-health indices, but their surrounding basins were low and required management for aquatic ecosystem health. The hotspot basins of the physicochemical factor(BOD) were the Nakdong River downstream basin, Suyeong River, Hoeya River, and the Nakdong River Namhae basin, whereas the coldspot basins were the upstream basins of the Nakdong River tributaries, including Andong Dam, Imha Dam, and Yeong River. The hotspots of the habitat and riverside environment factor(HRI) were different from the hotspots and coldspots of each factor in the LISA analysis results. In general, the habitat and riverside environment of the Nakdong River mainstream and tributaries, including the Nakdong river upstream, Andong Dam, Imha Dam, and the Hapcheon Dam basin, had good health. The coldspot basins of the habitat and riverside environment also showed low health indices of the biotic indices and physicochemical factors, thus requiring management of the habitat and riverside environment. As a result of the time-series analysis with a standard deviation ellipsoid, the areas with good aquatic ecosystem health of the organisms, habitat, and riverside environment showed a tendency to move northward, and the BOD results showed different directions and concentrations by the year of investigation. These aquatic ecosystem health analysis results can provide not only the health management information for each investigation spot but also information for managing the aquatic ecosystem in the catchment unit for the working research staff as well as for the water environment researchers in the future, based on spatial information.