• Korean Journal of Remote Sensing
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• v.19 no.4
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• pp.307-317
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• 2003

This paper presents an algorithm that automatically extracts buildings among many different features on the earth surface by fusing LIDAR data with panchromatic aerial images. The proposed algorithm consists of three stages such as point level process, polygon level process, parameter space level process. At the first stage, we eliminate gross errors and apply a local maxima filter to detect building candidate points from the raw laser scanning data. After then, a grouping procedure is performed for segmenting raw LIDAR data and the segmented LIDAR data is polygonized by the encasing polygon algorithm developed in the research. At the second stage, we eliminate non-building polygons using several constraints such as area and circularity. At the last stage, all the polygons generated at the second stage are projected onto the aerial stereo images through collinearity condition equations. Finally, we fuse the projected encasing polygons with edges detected by image processing for refining the building segments. The experimental results showed that the RMSEs of building corners in X, Y and Z were 8.1cm, 24.7cm, 35.9cm, respectively.

• Journal of KIBIM
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• v.13 no.3
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• pp.30-38
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• 2023

Building Information Models(BIM) provides rich geometric and attribute information throughout the entire life cycle of a building and infrastructure object, while Geographic Information System(GIS) enables the detail analysis of urban issues based on the geo-spatial information in support of decision-making. The Integration of BIM and GIS data makes it possible to create a digital twin of the land in order to effectively manage smart cities. In the perspective of integrating BIM data into GIS systems, this study performs literature reviews on georeferencing techniques and identifies limitations in carrying out the georeferencing process using attribute information associated with absolute coordinates probided by Industry Foundation Classes(IFC) as a BIM standard. To address these limitations, an automated georeferencing process is proposed as a pilot study to position a IFC model with the Local Coordinate System(LCS) in GIS environments with the Reference Coordinate System(RCS). An evaluation of the proposed approach over a BIM model demonstrates that the proposed method is expected to be a great help for automatically georeferencing complex BIM models in a GIS environment, and thus provides benefits for efficient and reliable BIM and GIS integration in practice.

• Journal of KIISE:Computer Systems and Theory
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• v.33 no.10
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• pp.777-788
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• 2006

This paper describes a displacement mapping technique which represents protruded shapes on the surface of an object. Previous approaches for image-based displacement mapping can represent only shapes depressed from the polygon surface. The proposed technique can represent shapes protruded from the underlying surface in real-time. Two auxiliary surfaces which are perpendicular to the underlying surface are added along the boundary of the polygon surface, in order to represent the pixels which overflow over the boundary of the polygon surface. The proposed approach can represent accurate silhouette of protruded shape. It can represent not only smooth displacement of protruded shape, but also abrupt displacement such as perpendicular protrusion by means of adding the supplementary texture information to the steep surface of protruded shape. By per-pixel instructions on the programmable GPU this approach can be executed in real-time. It provides an effective solution for the representation of protruded shape such as high-rise buildings on the ground.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.38 no.6
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• pp.599-610
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• 2020

The AED (Automated External Defibrillator) is not evaluated for spatial accuracy and temporal availability even if it is located within a building or a specific area that needed necessary to partition by spatial analysis and location allocation analysis. As a result of the analysis, the spatial analysis was performed using the existing public data of AED with applied the GIS location analysis method. A public institution (119 safety center, police box) was selected as a candidate for a public AED base that can operate 24 hours a day, 365 days a year according to the characteristics of each residential area. In addition, Thiessen Polygons were created for each candidate site and divided by regions. In the analysis of the service was analyzed regional in terms of accessibility to emergency medical services in consideration of the characteristics of AED, that emergency vehicles could arrive within 4 minutes of the time required for emergency medical treatment in most areas of the study area, but it did not areas outside of the city center. As a result, It was found that the operation of the AED base service center centered on vehicles of public institutions is effective for responding to AED patients at night and weekend hours. 19 Safety Center under and police box the jurisdiction of Daegu City to establish an AED service center for public institutions, location-based distance, attribute analysis, and minimization of overlapping areas that the method of using a vehicle appeared more efficient than using the existing walking type AED.