• Korean Journal of Remote Sensing
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• v.39 no.5_3
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• pp.1009-1029
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• 2023

Urban trees play a vital role in urban ecosystems,significantly reducing impervious surfaces and impacting carbon cycling within the city. Although previous research has demonstrated the efficacy of employing artificial intelligence in conjunction with airborne light detection and ranging (LiDAR) data to generate urban tree information, the availability and cost constraints associated with LiDAR data pose limitations. Consequently, this study employed freely accessible, high-resolution multispectral satellite imagery (i.e., Sentinel-2 data) to estimate fractional tree canopy cover (FTC) within the urban confines of Suwon, South Korea, employing machine learning techniques. This study leveraged a median composite image derived from a time series of Sentinel-2 images. In order to account for the diverse land cover found in urban areas, the model incorporated three types of input variables: average (mean) and standard deviation (std) values within a 30-meter grid from 10 m resolution of optical indices from Sentinel-2, and fractional coverage for distinct land cover classes within 30 m grids from the existing level 3 land cover map. Four schemes with different combinations of input variables were compared. Notably, when all three factors (i.e., mean, std, and fractional cover) were used to consider the variation of landcover in urban areas(Scheme 4, S4), the machine learning model exhibited improved performance compared to using only the mean of optical indices (Scheme 1). Of the various models proposed, the random forest (RF) model with S4 demonstrated the most remarkable performance, achieving R² of 0.8196, and mean absolute error (MAE) of 0.0749, and a root mean squared error (RMSE) of 0.1022. The std variable exhibited the highest impact on model outputs within the heterogeneous land covers based on the variable importance analysis. This trained RF model with S4 was then applied to the entire Suwon region, consistently delivering robust results with an R² of 0.8702, MAE of 0.0873, and RMSE of 0.1335. The FTC estimation method developed in this study is expected to offer advantages for application in various regions, providing fundamental data for a better understanding of carbon dynamics in urban ecosystems in the future.

• Korean Journal of Remote Sensing
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• v.33 no.6_3
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• pp.1223-1232
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• 2017

This paper presents an approach to detect changes caused by urban development over a large area using KOMPSAT optical images. In order to minimize the radiometric dissimilarities between the images acquired at different times, we apply the grid-based rough radiometric correction as a preprocessing to detect changes in a large area. To improve the accuracy of the change detection results for urban development, we mask-out non-interest areas such as water and forest regions by the use of land-cover map provided by the Ministry of Environment. The Change Vector Analysis(CVA) technique is applied to detect changes caused by urban development. To confirm the effectiveness of the proposed approach, a total of three study sites from Sejong City is constructed by combining KOMPSAT-2 images acquired on May 2007 and May 2016 and a KOMPSAT-3 image acquired on March 2014. As a result of the change detection accuracy evaluation for the study site generated from the KOMPSAT-2 image acquired on May 2007 and the KOMPSAT-3 image acquired on March 2014, the overall accuracy of change detection was about 91.00%. It is demonstrated that the proposed method is able to effectively detect urban development changes in a large area.

• Korean Journal of Remote Sensing
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• v.34 no.2_1
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• pp.167-178
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• 2018

Urban green areas or forest regions play an important role in lowering the air temperature of the surrounding areas. This cooling effect does not only affect inside of the green areas, but also extends into neighboring streets and buildings. In this study, the Land Surface Temperature (LST) are retrieved from the Landsat 8 satellite data for 8 clear days in Seoul, Korea from 2013 to 2015, and used for analyzing the cooling effect at an urban green region, Seonjeongneung, located in the southern part of Seoul. The LST distribution from the boundary of the Seonjeongneung presents that the cooling effect of the green areas was found to extend in many directions into the urban areas. The LST estimations of residential and commercial areas around the Seonjeongneung are also analyzed to assess how the green areas affect the type of land cover and the surroundings in the urban areas. Relatively lower LST for the residential areas from the Seonjeongneung boundary ranges from 100 to 250 m, resulting in an average cooling effect of $2.3^{\circ}C$. On the other hand, the LST distribution in the commercial areas shows that the effective distance of green areas are relatively low in the range of 0 to 200 m, which means the average cooling effect is approximately $0.3^{\circ}C$. This result shows that the cooling effect of the Seonjeongneung is clearly noticeable, particularly, the residential areas show greater cooling effect than commercial areas.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.3
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• pp.545-555
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• 2020

The purpose of this study is to derive the linkage between urban regeneration and district unit planning, in order to supplement the limitations of the spread of the effects of individual urban regeneration projects. To this end, institutional changes and previous studies with theoretical backgrounds were reviewed, the urban regeneration strategic plan and district unit plan cases in the spatial scope of Jeju Island were analyzed, and a unified administrative procedure to strengthen linkages was proposed. In addition, when selecting priorities for active regions, we reviewed how to use the indicators of involvement of residents, which enabled the project to be performed smoothly by grasping the participation of residents and the elements of complaints. Also a hypothetical target site was set up and suggested how to establish a district unit plan by type. Depending on the circumstances and environment of the site, the use of the land use plan and the regulation and mitigation of the district unit plan may be appropriately used to expect the inhabitants to expand their participation and revitalization. This study suggests ways to revitalize decayed areas beyond systematic urban planning in connection with systematic plans, to improve administrative procedures, and to promote bottom-up projects.

• Journal of the Korean association of regional geographers
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• v.21 no.2
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• pp.207-225
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• 2015

This study attempts to explore settlement and adaptation status involved in differing urban-to-rural migration types in Gyeongbuk Province and suggests policy implications based on this analysis. The attributes of urban-to-rural migrants in Gyeongbuk Province differ spatio-temporally, and their status of settlement and adaptation is also different depending on urban-to-rural migration types. "U-turn" migrants who are mostly first-generation rural-to-urban migrants with experience in farming and rural community life engage primarily in crop agriculture. "J-turns" and "I-turns," who have no experience in farming or rural community life, migrated for idyllic rural life. The household income of these types is relatively low compared to U-turn type. U-turns' degree of adaptation is relatively lower than the other types, and U-turn migrants mainly rely on family and community assets in order to solve problems. J-turns' and I-turns' degree of satisfaction is relatively high. However they typically have substantial difficulties in adapting due to lack of pre-migration preparation. Policy implications are : 'switching away from general and inclusive policies of support,' 'transition to policies embedded in the attributes of regions and migration types,' 'improvement of policy governance,' 'enhancement of support for pre-migration preparation and customized support based on the needs of migrants,' and 'comprehensive improvements of settlement environment to better integrate migrants with current residents.'.

• Journal of Environmental Impact Assessment
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• v.30 no.4
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• pp.187-202
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• 2021

This study examined the effectiveness of wind corridor construction by analyzing the thermal environment, cold air generation, ventilation, and geographical characteristics to improve urban thermal environment and establish the basis for specialized strategy in Changwon-si, Gyeongsangnam-do. Using spatial analysis and remote sensing techniques, surface temperature, land cover and land use, wind field, and slope were measured and through this, a wind corridor analysis model was constructed. As a result of the analysis as of 2020, Changwon-si generally has land cover characteristics that are advantageous for the generation of cold air, but the temperature in most urban areas is the highest, and the temperature in areas such as north Changwon area, Jinbukmyeon, Ung-dong, and Ungcheon-dong are relatively high. There was a typical trend of high average wind speed in mountain regions and low average wind speed in urban areas. Accordingly, the north Changwon area, the former Changwon downtown area, the Hogye-ri and Pyeongseong-ri areas, and the Changpo Bay area are derived as vulnerable areas to thermal environment, and various measures to reduce temperature and improve air quality that the inflow of cold air into the area considering the characteristics of each area and securing wind ventilation between the surrounding mountains, reservoirs, and park areas were proposed.

• Journal of the Korean association of regional geographers
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• v.13 no.4
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• pp.381-395
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• 2007

After the democratization process since 1988, the national scale voting behavior in congressional elections has changed from a rural-government party and urban-opposite party connection to a political regionalism oriented pattern. In this context, the case study with provincial border regions aims to investigate possible party identification change of the region, and to find a relationship between polling score ratio and socio-political characteristics of the candidates. As a result, Yeongdong shows a strong negation to the presumed Chungcheong local party and shows a continuous party identification with the Kyungsang local party. Muju reveals a more or less weakened identification with the Jeolla local party, on the contrary, Kimcheon shows a unchanged strong identification with the Kyungsang local party. The regional neighborhood effect was verified quite partly between the subdivision districts of the border regions. With a application of linear fitting method, it is certified that voters have attached great importance to the belonging party, native place, as well as political career of the candidates as a voting criterion.

• Journal of the Korean Institute of Landscape Architecture
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• v.38 no.5_2
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• pp.176-185
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• 2010

This study aimed to clarify meanings of Palkyung(八景) in different regions which can be considered as the prototype of the region's cultural landscape and also to confirm the change process by pointing out landscape characteristics and finally, to provide a foundation for the regions to establish their own identities, so they could be provided against the changes from developments in other areas. The relationship between the characteristics of landscape values and the components of 32 Palkyung in 4 places those are Gogunsan, Wido, Gunsan and Byunsan under Saemankeum area have been analyzed and evaluated from operational point of view to clarify the structure of the landscape concept. Some important differentiation points would be the sunset of the West Sea, sailing boats and the sceneries related to fishing as they are in the West Sea Islands and the coastal regions; and it clearly reflects the local customs and the characteristics of the landscapes. Each of Gogunsan, Wido and Gunsan Palkyung has 2 distance views with 4km of visible area while Byunsan Palkyung has only 1; and it is considered that because it is mountain area. Most of the Byunsan Palkyung has close range views except for Seohaenakjo and there are around 4 close range views in other areas. There were 4 landscape dominated influence areas each in Gunsan and Byunsan, which means that there are comparatively more close to middle range views. Moreover, each region contains 2 to 3 views of psychological influence but as mentioned, Byunsan has only 1 view of psychological influence. Therefore it is very important and valuable thing to consider the scenic relationship, preservation and reconstruction of Palkyung when planning the project.

• Journal of Korean Society for Atmospheric Environment
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• v.25 no.5
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• pp.432-449
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• 2009

In this study, the effects of high-resolution land cover on the simulation of near-surface meteorological fields were evaluated in two different coastal regions using Weather Research and Forecasting (WRF) model. These analyses were performed using the middle classification land cover data upgraded by the Korean Ministry of Environment (KME). For the purpose of this study, two coastal areas were selected as follows: (1) the southwestern coastal (SWC) region characterized by complex shoreline and (2) the eastern coastal (EC) region described a high mountain and a simple coastline. The result showed that the application of high-resolution land cover were found to be notably distinguished between the SWC and EC regions. The land cover improvement has contributed to generate the realistic complex coastline and the distribution of small islands in the SWC region and the expansion of urban and built-up land along the sea front in the EC region, respectively. The model study indicated that the improvement of land cover caused a temperature change on wide areas of inland and nearby sea for the SWC region, and narrow areas along the coastal line for the EC region. These temperature variations in the two regions resulted in a decrease and an increase in land-breeze and sea-breeze intensity, respectively (especially the SWC region). Interestingly, the improvement of land cover can contribute large enough to change wind distributions over the sea in coastal areas.

• Journal of the Economic Geographical Society of Korea
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• v.12 no.1
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• pp.96-110
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• 2009

To tackle the problem of regional economic and social disparities in Korea, the government of Roh, Mu-Hyun(2003-2007), launched a series of radical policies and programs to decentralize administrative activities of the capital region and stimulate economic growth in less developed regions, based on regional innovation systems and industrial cluster concepts. This paper highlights the Roh government's approach to reducing regional disparities, and makes some comments on the innovation cluster strategy by investigating the realities appearing in a major city, Daejeon. It concludes that many ministries of the Roh government created various competing, undifferentiated programs that were assigned too much money and energy, and drained resources from other governmental activities. In fact, very few programs show positive signs of achieving the goals of innovation in less developed regions, balancing the growth gaps between well-off regions and the rest of Korea, and generating overall economic growth for the country.