• Journal of Cadastre & Land InformatiX
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• v.44 no.2
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• pp.125-138
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• 2014

The portal is conceptualized as a discovery gateway to facilitate the communication and sharing of geographic data and information. Generally, Geospatial portal serve the different function and service according to the operational agents and goal. It was shown that Geospatial Portal might be constructed, based on the integration of the public data and Geospatial data portal, OpenAPI, shared Cloud Infrastructure. Ultimately, this study suggests the analysis results for Geospatial Information Prortal trends and contribute to the future development of Geospatial Information Open Platform(called Vworld).

• Journal of the Korean Association of Geographic Information Studies
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• v.23 no.1
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• pp.41-50
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• 2020

The National Geographic Information Institute of Korea takes digital aerial photograph images every two years to make and modify/renew the digital map. The cameras for aerial photogrammetry to capture these digital aerial photographs are divided into frame types and line types. Computer vision analysis of aerial photograph images was only possible for frame type. Thus, in this study, Line type aerial photograph images was intended to generate geospatial information through computer vision analysis, and forest geospatial information was created as a method for the utilization of aerial picture images. As a result, geospatial information generated by computer vision analysis of line type aerial photograph images showed that RMSE of horizontal and vertical position errors was less than quadruple that of GSD. Forest geospatial information was generated using geospatial information generated by computer vision analysis. It was confirmed that extraction of the crown of tree and calculation of tree height are possible. Through this study, it is expected that utilization of aerial photograph images will be improved.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.29 no.5
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• pp.449-457
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• 2011

As automated image processing techniques have been required in multi-temporal/multi-sensor geospatial image applications, use of automated but highly invariant image matching technique has been a critical ingredient. Note that there is high possibility of geometric and spectral differences between multi-temporal/multi-sensor geospatial images due to differences in sensor, acquisition geometry, season, and weather, etc. Among many image matching techniques, the SIFT (Scale Invariant Feature Transform) is a popular method since it has been recognized to be very robust to diverse imaging conditions. Therefore, the SIFT has high potential for the geospatial image processing. This paper presents a performance test results of the SIFT on geospatial imagery by simulating various image differences such as shear, scale, rotation, intensity, noise, and spectral differences. Since a geospatial image application often requires a number of good matching points over the images, the number of matching points was analyzed with its matching positional accuracy. The test results show that the SIFT is highly invariant but could not overcome significant image differences. In addition, it guarantees no outlier-free matching such that it is highly recommended to use outlier removal techniques such as RANSAC (RANdom SAmple Consensus).

• Journal of the Korean Association of Geographic Information Studies
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• v.20 no.1
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• pp.113-126
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• 2017

This study aimed to quantitatively analyze the trends in environmental research that utilize environmental geospatial information through text mining, one of the big data analysis technologies. The analysis was conducted on a total of 869 papers published in the Republic of Korea, which were collected from the National Digital Science Library (NDSL). On the basis of the classification scheme, the keywords extracted from the papers were recategorized into 10 environmental fields including "general environment", "climate", "air quality", and 20 environmental geospatial information fields including "satellite image", "numerical map", and "disaster". With the recategorized keywords, their frequency levels and time series changes in the collected papers were analyzed, as well as the association rules between keywords. First, the results of frequency analysis showed that "general environment"(40.85%) and "satellite image"(24.87%) had the highest frequency levels among environmental fields and environmental geospatial information fields, respectively. Second, the results of the time series analysis on environmental fields showed that the share of "climate" between 1996 and 2000 was high, but since 2001, that of "general environment" has increased. In terms of environmental geospatial information fields, the demand for "satellite image" was highest throughout the period analyzed, and its utilization share has also gradually increased. Third, a total of 80 correlation rules were generated for environmental fields and environmental geospatial information fields. Among environmental fields, "general environment" generated the highest number of correlation rules (17) with environmental geospatial information fields such as "satellite image" and "digital map".

• Proceedings of the KSRS Conference
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• 2002.10a
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• pp.745-745
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• 2002

Both geophysical and geospatial data provide important information in the establishment of the optimal telecommunication systems especially in the mobile telecommunication environment. The objective of this study is to utilize geophysical properties and geospatial information in the analysis of the telecommunication environment through point-to-point wave property modeling. Geophysical properties associated with wave propagation parameters of the earth surface were analyzed based on hierarchical land classification using Landsat ETM＋ and IKONOS images. Three-dimensional geospatial information was obtained by processing stereo aerial images. The results show that the accurate geospatial information and reliable geosphysical property of the surface improve the prediction of receiving power of the receivers located near corners of the buildings where diffractions occur. The wave property model developed from accurate telecommunication environment could be applied to optimal cell planning and delay time analysis.

• Spatial Information Research
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• v.20 no.6
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• pp.1-11
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• 2012

To solve the housing supply problems which are combined with economic, social, environmental and urban spatial structural aspects, it is needed to analyze housing supply based on the analysis model. This study aims to draw the construction of the housing geospatial information for housing supply model. For these purposes, we construct the housing geospatial information and draw case studies on information utilization based on the precedent studies and relevant systems about housing geospatial information. From the result, we construct the geospatial information according to spatial unit and draw standardization of connected information between housing supply information and housing geospatial information. Also we found that it is essential to use a building and parcel level housing geospatial information for housing supply. In the future, it will be needed to construct the housing supply information from qualitative aspect for dwelling and to establish a utilization strategy.

• Proceedings of the Korea Water Resources Association Conference
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• 2020.06a
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• pp.85-85
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• 2020

South Korea experiences few large scale erosion and sedimentation problems, however, there are numerous local sedimentation problems. A reliable and consistent approach to modelling and management for sediment processes are desirable in the country. In this study, field measurements of sediment concentration from 34 alluvial river basins in South Korea were used with the Modified Einstein Procedure (MEP) to determine the total sediment load at the sampling locations. And then the Flow Duration-Sediment Rating Curve (FD-SRC) method was used to estimate the specific degradation for all gauging stations. The specific degradation of most rivers were found to be typically 50-300 tons/㎢·yr. A model tree data mining technique was applied to develop a model for the specific degradation based on various watershed characteristics of each watershed from GIS analysis. The meaningful parameters are: 1) elevation at the middle relative area of the hypsometric curve [m], 2) percentage of wetland and water [%], 3) percentage of urbanized area [%], and 4) Main stream length [km]. The Root Mean Square Error (RMSE) of existing models is in excess of 1,250 tons/㎢·yr and the RMSE of the proposed model with 6 additional validations decreased to 65 tons/㎢·yr. Erosion loss maps from the Revised Universal Soil Loss Equation (RUSLE), satellite images, and aerial photographs were used to delineate the geospatial features affecting erosion and sedimentation. The results of the geospatial analysis clearly shows that the high risk erosion area (hill slopes and construction sites at urbanized area) and sedimentation features (wetlands and agricultural reservoirs). The result of physiographical analysis also indicates that the watershed morphometric characteristic well explain the sediment transport. Sustainable management with the data mining methodologies and geospatial analysis could be helpful to solve various erosion and sedimentation problems under different conditions.

• Spatial Information Research
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• v.22 no.2
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• pp.73-87
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• 2014

The fact that the limits of information recency, diversity, and usability are mainly caused by the supply oriented geospatial data and service development is commonly recognized. It is recently tried to overcome the limits by facilitating user experience and VGI(Volunteered Geographic Information) in several geospatial web services. This study suggests 10C framework of geospatial web service for VGI through review and examination of previous research. Based on the 10C framework, the value chain system of 23 use cases relevant to the geospatial web service involving the creation of user's VGI is investigated. The result of the value chain analysis is applied to examine and formulate the strategies to generate value addition from public spatial information with respect to creation, aggregation, delivery, and consumption process of VGI.

• Wind and Structures
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• v.28 no.6
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• pp.381-388
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• 2019

This paper described the application of Geospatial Analysis in determining mean wind speed, $V_h$ for wind load calculation imposed to electrical transmission tower structural design. The basic wind speed data on available station obtained from Malaysian Meteorology Department is adjusted by considering terrain and ground roughness factor. The correlation between basic wind speed, terrain factor and ground roughness stated in EN-50341-1 is used to obtain the $V_h$ for overhead transmission line elements 50 m above ground. Terrain factor, $k_r$ and ground roughness, $z_0$ in this study are presented by land use types of study area. Wind load is then calculated by using equation stated in design code EN-50341-1 by using the adjusted mean wind speed. Scatter plots of $V_h$ for different $k_r$and $z_0$ are presented in this paper to see the effect of these parameters to the value of $V_h$. Geospatial analysis is used to represent the model of $V_h$. This model can be used to determine possible area that will subject to wind load which severe to the stability of transmission tower and transmission line.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.36 no.4
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• pp.213-221
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• 2018

South Korea has been reluctant to open its geospatial information overseas to ensure security as a divided country. However, this cannot continue as the domestic and international environments related to geospatial information and the industrial ecosystem of information and communication technologies have been changing dramatically. Within this context, this study aims to analyze the causal relations among relevant variables and how they change and interact with time using a systems thinking process. First, causal maps were created for the domains of national security, map-based convergence service, and corporate competition. Then, the causal maps for each domain were integrated, based on which the points for policy intervention and dominant feedback loops were identified. The analysis results showed that securing the self-sufficiency of domestic geospatial businesses is a key element to determine the whole causal map, and the variable that changes the dominant feedback loop from a vicious circle to a virtuous one is the decision to open geospatial information overseas. In this study, I found the policy leverage that is a policy intervention point that can produce a great effect with little input by building a causal map of the interactions between major variables. This study is significant in that it identified and analyzed the dominant feedback loop as to which causal structure would dominate the system in the long term. The results of this study can be used to discuss not only the impacts of map data overseas opening on the national security and geospatial information industry, but also the interactions in the future when Google or other global companies request to release the geospatial information.