• Journal of Korea Water Resources Association
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• v.38 no.5 s.154
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• pp.379-390
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• 2005

This study is to trace the change of stream shape using the past series of aortal photographs and topographic maps, and to compare the land use changes of inland along the stream. For the Gyeongan first & second class of local stream, aerial photographs of 1966, 1981 and 2000 were selected and ortho photographs were made with interior orientation and exterior orientation, respectively. In addition, topographic maps of 1914 - 1915 were used to compare with stream of 1966, 1981 and 2000. As apparent changes of the stream, the consolidated reaches of stream with levee construction were straightened and their stream width widened. Especially the stream width of inlet part of Paldang lake was widened almost twice because of the rise of water level by dam construction in 1974. The land use maps (1966, 1981, 2000) of riparian areas were also made, respectively and classified into 6 categories (water, forest, agricultural land, urban area, road, sandbar) by digitizing, The main changes of land use were agricultural land, urban area, road and sandbar.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.13 no.2
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• pp.169-176
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• 1995

Change detection is the technique to represent the change of pixel by pixel and band by band between $t_1\;and\;t_2$ times. In this study, authors analize the beach-sand movement using digital image analysis, interpolation and digital terrain model by leveling every years at a coastal area. This paper suggests the useful beach-maintainance plan based on the sand movement and its direction, direction and influence of ocean current, change of oceansand erosion and sedimentation, and area of erosion and sedimentation.

• Journal of the Korean Society of Industry Convergence
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• v.26 no.1
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• pp.163-173
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• 2023

In this study, topographic change analysis was performed on the Nak-dong River estuary area. The factors affecting the changes in the bathymetry of the Nak-dong River estuary were analyzed using data from the discharge, suspended sediments, and rainfall of the Nak-dong River barrier as analysis data. As a result, erosion and sedimentation are judged to appear repeatedly due to complex effects such as discharge of the estuary barrier of the Nak-dong River and invasion of the open sea waves, and it is judged that there is no one-sided tendency. However, as a result of checking the data in the second half of 2020, it was possible to confirm a large amount of erosion, which is different from the past data. It is clear that this is a result beyond the trend of erosion in the first half and sedimentation in the second half. In the summer of 2020, the rainy season lasted for more than a month and torrential rains occurred, which seems to be due to about three times higher rainfall than other periods, and erosion is believed to have occurred as the discharge increased rapidly compared to the time deposited by river water outflow. In addition, compared to other times, the influence of many typhoons in the summer of 2020 is believed to have affected the topographical change at the mouth of the Nak-dong River.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.31 no.1
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• pp.69-78
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• 2013

Recently, as GIS industry has substantially grown up, convergence between industries such as the application coverage of surveying and cadastral information is gradually on the increase. The new approach of convergence between topographic surveying and cadastral survey is indispensable to make the change of geospatial environment ready and to maximize the utilization of National Spatial Data Infrastructure(NSDI). The purpose of this paper is to seek the way of synergistic improvement in topographic surveying and cadastral survey in comprehensive aspects of national geospatial information. First, we reviewed policy environment to clearly establish aim of convergence and promising perspective of GIS industry policy, considering NSDI. In addition, we examined current state of administration (organization, human resource, service) and institution situation. We came up with interior ability and external policy environment as well as critical success factor for the synergistic convergence by using SWOT analysis. Lastly, we developed basic perspective of convergence and improvement model and concrete scheme for stakeholder to complementary make progress. We can come to conclusion that the convergence of topographic surveying and cadastral survey should be not only carried in macro outline of successful NSDI but also committed to completion and maintenance of GIS framework.

• Journal of Cadastre & Land InformatiX
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• v.49 no.1
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• pp.103-112
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• 2019

Extraction of region of interest for satellite image classification is one of the important techniques for efficient management of the national land space. However, recent studies on satellite image classification often depend on the information of the selected image in selecting the region of interest. This study propose an effective method of selecting the area of interest using the continuous digital topographic map constructed from high resolution images. The spatial information used in this research is based on the digital topographic map from 2013 to 2017 provided by the National Geographical Information Institute and the 2015 Sejong City land cover map provided by the Ministry of Environment. To verify the accuracy of the extracted area of interest, KOMPSAT-3A satellite images were used which taken on October 28, 2018 and July 7, 2018. The baseline samples for 2015 were extracted using the unchanged area of the continuous digital topographic map for 2013-2015 and the land cover map for 2015, and also extracted the baseline samples in 2018 using the unchanged area of the continuous digital topographic map for 2015-2017 and the land cover map for 2015. The redundant areas that occurred when merging continuous digital topographic maps and land cover maps were removed to prevent confusion of data. Finally, the checkpoints are generated within the region of interest, and the accuracy of the region of interest extracted from the K3A satellite images and the error matrix in 2015 and 2018 is shown, and the accuracy is approximately 93% and 72%, respectively. The accuracy of the region of interest can be used as a region of interest, and the misclassified region can be used as a reference for change detection.

• Journal of Korean Society for Geospatial Information Science
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• v.13 no.2 s.32
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• pp.13-20
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• 2005

Upon the request of balanced development of the country and making inroads into the continent of China the development of the west coast was begun in the late 1980s, which has been being continued till recently under the blueprint of making the western part of the capital region to be the hub of northeastern Asia. As more lively development is expected to continue in the area, there are many occurrences of change in topology and terrain in the west coast. This study was done to detect the topographic and terrain change of the vicinity of the west coast. To make the basic map of the change in topology and terrain, the mosaic images were made using landsat images. The accuracy of the images was examined by comparing them with GCP through 1:25,000's digital map. After that, among the resultant images of the 1970s and 2000s, those of Sihwa, Hwaong and Ansan, the lands reclaimed by drainage were compared to observe the change in the area. From the results, it was concluded that, in case of the land the topological change was not so big due to the development in the reclaimed land or the bare land, and the area of agriculture and downtown increased, the drainage and bare land area decreased by comparing the change of land use.

• Spatial Information Research
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• v.12 no.1
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• pp.43-56
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• 2004

Basically a land parcel consists of a land parcel number, land category, land boundary and area, and land value is mostly determined by the land category. Generally people want to change their land use to increase their land value so that they can expect more benefits from the land. However, changing land use causes several problems with land properties, haphazard urban expansions and land category non-coincidences. Unfortunately, no effective solutions exist for land category non-coincidence problems. In this study, we proposed a methodology that can classify the land category based land covers using high resolution satellite images and digital topographic maps. For this, we obtained a parcel based land use/cover classification map. Using both this classification map and a digital cadastral map, we inspected land category non-coincidences. As a result, land category non-coincidence rates could be statistically measured and interpreted and demonstrate a possibility that we could quantitatively interpretate and measure cadastral non-coincidence automatically.

• Journal of Korean Society for Geospatial Information Science
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• v.15 no.2 s.40
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• pp.77-85
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• 2007

According to the survey data during the Japanese Occupation Period, the length of South Korea's coastline is about 11,542 km, including the coastlines of land and islands. It will be very expensive and time-consuming to revise/renew accurately this coastline data through site survey, it will cost great money and time. Also, various development projects such as reclamation works on public waters, constructions of ports/harbors, etc. are frequently changing the coastal areas and coastlines, causing many renewal projects on coastal maps. For such reason, appropriate alternatives for site survey are necessary. This paper demonstrate the utilization of RTK-GPS survey data, qualitative analysis and 3D topographic analysis for extracting the change in five coastal areas (Songjeong, Haeundae, Kwanganri, Songdo and Dadaepo). The local experimental areas subjected for this research were limited to five coastal areas near Busan.

• Journal of Korea Water Resources Association
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• v.55 no.spc1
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• pp.1223-1234
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• 2022

Efforts for reducing greenhouse gas emission coping with climate change have also been performed in the field of water and wastewater works. In particular, the technical development for reducing energy has been applied in operating water distribution system. The reduction of energy in water distribution system can be achieved by reducing structural loss induced by topographic variation and operational loss induced by leakage and friction. However, both analytical and numerical approaches for analyzing energy budget of water distribution system has been challengeable because energy components are affected by the complex interaction of affecting factors. This research drew mathematical equations for 5 types of state (hypothetical, ideal, leak-included ideal, leak-excluded real, and real), which depend on the assumptions of topographic variation, leakage, and friction. Furthermore, the derived equations are schematically illustrated and applied into simple water network. The suggested method makes water utilities quantify, classify, and evaluate the energy of water distribution system.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2004.11a
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• pp.275-279
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• 2004

This study was done to detect the topographic and terrain change of the vicinity of the west coast. To make the basic map of the change in topology and terrain, the mosaic images were made using the images from the satellite, which were given the geometric correction based on the GCP (Ground Control Point) and DEM (Digital Elenation Model) data. The accuracy of the images was examined by .empaling them with CCP through 1:25,000's digital map. After that, among the resultant images of the 1970s and 2000s, those of Sihwa, Hwaong and Ansan, the lands reclaimed by drainage were compared to observe the change in the area. From this study, the accuracy of the images of the west coast from satellite could be acquired and the change of the topology and terrain was detected effectively. From the results, it was known that, in case of the land the topological change was not so big due to the development in the reclaimed land or the bare land. In Sihwa, the size of the land was increased 180 $\textrm{km}^2$ and that of the seashore was decreased 110 km. in Hwaong the size was increased 50 $\textrm{km}^2$ and in Ansan the city space was increased 71 $\textrm{km}^2$ due to the formation of the industrial complex.