• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.31 no.5
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• pp.365-373
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• 2013

Tile caching technology is a commonly used method that optimizes the delivery of map imagery across the internet in modern WebGIS systems. However the poor performance of the map tile cache update is one of the major causes that hamper the wider use of this technique for datasets with frequent updates. In this paper, we introduce a new algorithm, namely, Partial Area Cache Update (PACU) that significantly minimizes redundant update of map tiles where the update frequency of source map data is very large. The performance of our algorithm is verified with the cadastral map data of Pyeongtaek of Gyeonggi Province, where approximately 3,100 changes occur in a day among the 331,594 parcels. The experiment results show that the performance of the PACU algorithm is 6.6 times faster than the ESRI ArcGIS SERVER$^{(r)}$. This algorithm significantly contributes in solving the frequent update problem and enable Web Map Tile Services for data that requires frequent update.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.12
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• pp.232-241
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• 2016

Among city parks, children's parks are more accessible than other parks in the city, and there are many users. They are used not only for children's playgrounds, but also for relaxation and leisure spaces for local residents. On the other hand, as a result of focusing on the quantitative increase by the engineering division by the Urban park Act, the consideration of the users of various classes is insufficient. The purpose of this study was to analyze the actual use of children parks in single - family housing and communal housing areas, and to identify the problems and future directions of the use of children parks. For this purpose, a case study and a document survey were conducted. First, through scholarship research, the theoretical review and the present situation were summarized based on the data, such as the papers and research reports related to the existing children's park. The status of the location, facilities and management were then identified through interviews and site visits with the children's park management staff. As a result, the children's park was utilized as a leisure space with high accessibility in the living area. As a result, the residence time of most users was within 1 hour to 2 hours. In particular, use by elderly people was higher than the use by children. Therefore, it would be desirable to design the future planning of the children's parks and to plan the arrangement in accordance with the future - oriented multi - purpose neighborhood type children's park.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.5
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• pp.507-517
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• 2017

This study suggests that the diversity of parks is necessary because the number of children, who are the main users in children's parks, is decreasing and the use of parks by older people is increasing. In particular, the present aging society is trying to propose a multi-purpose park to solve the problem of the elderly leisure. To do this, this study surveyed domestic and foreign children's parks and selected study sites to understand the usage patterns of children's parks. As a result of surveying the location of the park to select the study sites, most children's parks were found mostly in single family housing areas and multi-family housing areas. As a result of the survey, it was found that the children's parks consisted of streets and areas by the 'City Parks and Greenery Act' and they were uniform. This paper presents basic data for the development of a model for producing a multipurpose park that can be used for children's parks by the elderly. The subjects of this study were selected from 7 districts of Daegu city, which were classified into single family housing areas and multi-family housing areas. As a result, the arrangement of various facilities in the children's park is insufficient, and it was uniform without a design motive and contents. Therefore, the utilization rate of various age groups could be increased by developing a multi-purpose park model for a children's park.

• Journal of the Korean Society for Railway
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• v.10 no.6
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• pp.685-691
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• 2007

In this paper through Honan high-speed railroad which is planned with the north and south axis, we will verify the feasibility of the coordinate conversion using railroad control points after regarding current planned-railroad as the linear central axises. From analysis, distortion of Y axis varies 21 cm to 40 cm diminishing to a gentle straight line, distortion of X axis varies 14 cm to 29 cm. Through a revision, the deviation value between the coordinates were 6 mm to 9 mm and it satisfied the allowable error of national geographic information institute which is following ITRF (International Terrestrial Reference Frame) and cadastral boundary survey (10 cm). consequently the coordinate conversion is possible using railroad control points as common control points.

• Proceedings of the Korea Water Resources Association Conference
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• 2008.05a
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• pp.194-198
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• 2008

Significant soil erosion and water quality degradation issues are occurring at highland agricultural areas of Kangwon province because of agronomic and topographical specialities of the region. Thus spatial and temporal modeling techniques are often utilized to analyze soil erosion and sediment behaviors at watershed scale. The Soil and Water Assessment Tool (SWAT) model is one of the watershed scale models that have been widely used for these ends in Korea. In most cases, the SWAT users tend to use the readily available input dataset, such as the Ministry of Environment (MOE) land cover data ignoring temporal and spatial changes in land cover. Spatial and temporal resolutions of the MOE land cover data are not good enough to reflect field condition for accurate assesment of soil erosion and sediment behaviors. Especially accelerated soil erosion is occurring from agricultural fields, which is sometimes not possible to identify with low-resolution MOD land cover data. Thus new land cover data is prepared with cadastral map and high spatial resolution images of the Doam-dam watershed. The SWAT model was calibrated and validated with this land cover data. The EI values were 0.79 and 0.85 for streamflow calibration and validation, respectively. The EI were 0.79 and 0.86 for sediment calibration and validation, respectively. These EI values were greater than those with MOE land cover data. With newly prepared land cover dataset for the Doam-dam watershed, the SWAT model better predicts hydrologic and sediment behaviors. The number of HRUs with new land cover data increased by 70.2% compared with that with the MOE land cover, indicating better representation of small-sized agricultural field boundaries. The SWAT estimated annual average sediment yield with the MOE land cover data was 61.8 ton/ha/year for the Doam-dam watershed, while 36.2 ton/ha/year (70.7% difference) of annual sediment yield with new land cover data. Especially the most significant difference in estimated sediment yield was 548.0% for the subwatershed #2 (165.9 ton/ha/year with the MOE land cover data and 25.6 ton/ha/year with new land cover data developed in this study). The results obtained in this study implies that the use of MOE land cover data in SWAT sediment simulation for the Doam-dam watershed could results in 70.7% differences in overall sediment estimation and incorrect identification of sediment hot spot areas (such as subwatershed #2) for effective sediment management. Therefore it is recommended that one needs to carefully validate land cover for the study watershed for accurate hydrologic and sediment simulation with the SWAT model.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.4
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• pp.1327-1334
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• 2014

Linear form of public works such as roads, railways and rivers, generally used as long work crossing administrative districts, can be several hundreds km length and narrow. These linear forms use SCM sheets, which do not include the quadrangle shape, to make a public announcement of topographical drawing in order to get the work approval. the Integrated measurement channel investigation and cadastral act that are established in 2009 apply the ITRF for the composition of design and construction books and coordinates of topographical map in order to get the work approval. However according to the article 5 of additional clause, while the cadastre is maintaining local coordinates, if there is a technical error in the content of the Public Announcement of Topographical Drawing that used the SCM, the question of responsibility of land borders and the efficacy or not of the announcement is raised as an administrative measure. After analysing the causes and enforcing coordinate conversion and correction taking into account linear form work's features, the result was reflected in the existing SCM. As a conclusion, the present study proposes the improvement of the procedures of the Public Announcement of Topographical Drawing.

• Spatial Information Research
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• v.19 no.5
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• pp.1-11
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• 2011

This study mainly focused on the method of accurately extracting damage information in the im agery change detection process using the constructed high resolution aerial im agery. Bongwha-gun in Gyungsangbuk-do which had been severely damaged from a localized torrential downpour at the end of July, 2008 was selected as study area. This study utilized aerial im agery having photographing scale of 30cm gray image of pre-disaster and 40cm color image of post-disaster. In order to correct errors from the differences of the image resolution of pre-/post-disaster and time series, the prelim inary phase of image processing techniques such as normalizing, contrast enhancement and equalizing were applied to reduce errors. The extent of the damage was calculated using one to one comparison of the intensity of each pixel of pre-/post-disaster im aged. In this step, threshold values which facilitate to extract the extent that damage investigator wants were applied by setting difference values of the intensity of pixel of pre-/post-disaster. The accuracy of optimal image processing and the result of threshold values were verified using the error matrix. The results of the study enabled the early exaction of the extents of the damages using the aerial imagery with identical characteristics. It was also possible to apply to various damage items for imagery change detection in case of utilizing multi-band im agery. Furthermore, more quantitative estimation of the dam ages would be possible with the use of numerous GIS layers such as land cover and cadastral maps.

• Journal of the Korean Association of Geographic Information Studies
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• v.19 no.1
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• pp.80-93
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• 2016

Parcel boundary demarcation in agricultural area is commonly performed by terrestrial surveying methods, which have been pointed out as drawbacks to require consuming too much time and heavy expenditure. With the developments of high performance digital aerial cameras, however, studies on cadastral boundary demarcation with an aerial photogrammetric method attract a great attention in recent years. In this paper, an approach is presented to rapidly demarcate parcel boundaries coinciding with real ground ones in agricultural areas by extracting boundaries from the high resolution aerial orthoimages based on aerial targets. In order to investigate the feasibility of the proposed method, the accuracy of coordinates and area of parcel boundaries extracted from the aerial targets appeared in orthoimages compared with that of terrestrial boundary surveying results over the selected two test agricultural areas. Aerial image data were processed taken by a ADS80 digital camera with a GSD of 8cm in Changwon region, and by a DMCII camera with a GSD of 5cm in Suwon respectively. The result shows that the accuracy of parcel demarcation using aerial images is within the tolerance limits of coordinates and areas compared with that of terrestrial surveying. The proposed method using aerial target-based high resolution aerial images is therefore expected to be usefully applied in the agricultural parcel demarcation.

• Journal of the Korean Association of Geographic Information Studies
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• v.4 no.2
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• pp.17-26
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• 2001

The Purpose of this study is to provide an effective way of developing GIS to UIS at the local level. For this purpose, the study typologically reviews the developing processes of UIS and utilizes a case study as research method. As the case, the study selects three types of UIS such as FM based UIS(Kwacheon), Urban Planning based UIS(Cheungju), and LIS based UIS(Taegu Nam-Gu). Based on these three UISs, the study concludes as follows. First, the developing process of GIS to UIS began with isolated approach through integrated model and finally to internet UIS. Second, UISs follows similar processes to that of GIS construction. Third, local governments focus on the development of FM based UIS of which construction budget is financed by the central government. Based on these findings, the study provides policy alternatives for the successful construction of UIS.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.32 no.3
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• pp.168-182
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• 2014

Several Sungsi Gardens were built up in Old West Village during the period of the Joseon Dynasty. Most of them were painted as True-View landscape painting. This study aims at examining original locations of representative gardens of the Old West Village by empirical investigation of related True-View landscape paintings. It seeks to demonstrate the garden landscape in True-View landscape painting by utilizing ArcGIS, 3D topographic modeling to observe geographical locations and landscape more realistically. After forming 3D topographic modeling of estimated locations of the gardens, location of objects at composition of 3D modeling similar to True-View landscape painting was found by shifting viewpoints. And by overlapping the cadastral map on the modeling, we could verify the current lot number of the garden sites. The interpretation of processes and results are as follows. In the early stage, Chungpunggye garden was built at the very end of Mt. InWang valley. The site is hidden from the outside, and appeared as 'Enclosed Landscape'. In the middle stage, Chunghuigak garden was built between Okryu-dong valley and the surrounding ridge. It appeared as 'Semi-Opened Landscape'. In the late stage, Seowon garden was built at the highest level of the ridge among the research areas. It appeared as 'Prospective Landscape'. In the last period, Songsukwon garden, was built at a point of contact of the ridge end and surrounding residential area. So it appeared as 'Opened Landscape' to the town. In other words, the location, landscape and social function of the gardens in Old West Village had been gradually opened in Joseon Dynasty.