• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.35 no.2
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• pp.81-90
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• 2017

This study aimed to construct an integrated database using the same spatio-temporal unit by employing various public-data types with different real-time information provision cycles and spatial units. Towards this end, three temporal interpolation methods (piecewise constant interpolation, linear interpolation, nonlinear interpolation) and a spatial matching method by district boundaries was proposed. The case study revealed that the linear interpolation is an excellent method, and the spatial matching method also showed good results. It is hoped that various prediction models and data analysis methods will be developed in the future using different types of data in the analysis database.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.30 no.1
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• pp.49-58
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• 2012

Buildings become complex and diverse with time. It is difficult to extract individual buildings using only an optical image, because they have similar spectral characteristics to objects such as vegetation and roads. In this study, we propose a method to extract building area and boundary through integrating airborne Light Detection and Ranging(LiDAR) data and aerial images. Firstly, a binary edge map was generated using Edison edge detector after applying Adaptive dynamic range linear stretching radiometric enhancement algorithm to the aerial image. Secondly, building objects on airborne LiDAR data were extracted from normalized Digital Surface Model and aerial image. Then, a temporary building areas were extracted by overlaying the binary edge map and building objects extracted from LiDAR data. Finally, some building boundaries were additionally refined considering positional accuracy between LiDAR data and aerial image. The proposed method was applied to two experimental sites for validation. Through error matrix, F-measure, Jaccard coefficient, Yule coefficient, and Overall accuracy were calculated, and the values had a higher accuracy than 0.85.

• International conference on construction engineering and project management
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• 2017.10a
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• pp.42-51
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• 2017

Due to the high degree of mechanization and the good environmental benefits, the prefabricated buildings are being promoted in China. The construction site layout of the prefabricated buildings has important influence on its safety benefit. However, few scholars have studied the safety problem on it. Firstly, in order to give a follow-up study foreshadowing the characteristics of prefabricated buildings are analyzed, the research assumptions are given and three types of safety buffers are established. And then a mult-objective model for the prefabricated buildings site layout is presented: taking into account the limits of noise, the coverage of the tower crane and the possibility of exceeding boundaries and overlapping, the constraints are and designed established respectively; Based on the improved System Layout Planning (SLP) method, the efficiency\cost\safety interaction matrices among the facilities are also founded for objective function. For the sake of convenience, a hypothetical facility layout case of the prefabricated building is used, the optimal solution of that is obtained in MATLAB with particle swarm algorithm (PSO), which proves the effectiveness of the model presented in this paper.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.25 no.6_1
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• pp.507-516
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• 2007

Segmentation and organization of the LiDAR (Light Detection and Ranging) data of the Earth's surface are difficult tasks because the captured LiDAR data are composed of irregularly distributed point clouds with lack of semantic information. The reason for this difficulty in processing LiDAR data is that the data provide huge amount of the spatial coordinates without topological and/or relational information among the points. This study introduces LiDAR data segmentation technique by utilizing histograms of the LiDAR height image data and analyzing roof shape for 3D reconstruction and visualization of the buildings. One of the advantages in utilizing LiDAR height image data is no registration required because the LiDAR data are geo-referenced and ortho-projected data. In consequence, measurements on the image provide absolute reference coordinates. The LiDAR image allows measurement of the initial building boundaries to estimate locations of the side walls and to form the planar surfaces which represent approximate building footprints. LiDAR points close to each side wall were grouped together then the least-square planar surface fitting with the segmented point clouds was performed to determine precise location of each wall of an building. Finally, roof shape analysis was performed by accumulated slopes along the profiles of the roof top. However, simulated LiDAR data were used for analyzing roof shape because buildings with various shapes of the roof do not exist in the test area. The proposed approach has been tested on the heavily built-up urban residential area. 3D digital vector map produced by digitizing complied aerial photographs was used to evaluate accuracy of the results. Experimental results show efficiency of the proposed methodology for 3D building reconstruction and large scale digital mapping especially for the urban area.

• Journal of the Korean Institute of Landscape Architecture
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• v.37 no.6
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• pp.48-56
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• 2010

Since ancient times, Korea has been called a land of beauty. Scenic sites under the Cultural Properties Protection Act include picturesque places that are famous for their natural scenic beauty as well as their historical and cultural value. Scenic sites are managed as natural assets to promote their preservation and use. However, the management of scenic sites can produce adverse effects on regional development and ownership rights. Moreover, the purpose of their designation as cultural assets is not fully understood because scenic sites are managed by focusing on restraint on users' act the same as was applied to historic sites. Therefore, the purpose of this study is to protect inhabitants' rights of ownership by arranging the boundaries of designated areas and by providing standard permission for condition changes in the Buryeongsa Valley, which was designated as a Scenic Site in 1979. The results of this study can be summarized as follows: First, arranging the boundaries of the designated area includes the arrangement of the edge lines standardized on the visual range of the mountain ridge, preventing the loss of landscape beauty in the designated district; the internal clearing district focuses on the existing settlement. Gearing the designated areas after the arrangement of the boundaries results in $11,928,932m^2$, 38.6% compared to the existing designated areas. Second, it establishes a 500m buffer zone inside the radius of the boundary of the cultural asset as a standard for condition changes that seriously affect landscape preservation. Third, the standards for permission on building 'height regulations' are divided into flat and gable, according to the roof shape. The adopted standard is 8m high for 2 story flat roofs, and 12m high for 2 story gable roofs.

• Journal of the Korea Institute of Building Construction
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• v.15 no.3
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• pp.317-327
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• 2015

Many construction projects have extensively adopted building information modeling (BIM), and various institutions and standards have been developed domestically in Korea. However, the current process that is used to calculate building space area has a significant shortcoming in that there are two different laws to apply the method of measurement considering space boundaries for building element guidelines. For example, space area can be calculated by a polygon, which is modeling using a BIM-based computer aided design program, such that the space polygon is always exported as an inner-edge type. In this paper, we developed an automated algorithm to convert coordinates of space representation using industry foundation classes based BIM data. The proposed algorithm will enable engineers responsible for space management to use a BIM-based model directly in the space programming process without having to do additional work. The proposed process can help ensure that space area is more accurately and reliably.

• Journal of the Korean Society of Industry Convergence
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• v.2 no.2
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• pp.11-21
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• 1999

This objective of this paper is to investigate the evaluation and indiction of human thermal comfort in building environment. The issue of defining the boundaries of acceptable thermal comfort conditions in buildings and urban may have significant implication for building design and also may have urban design by climate considerations. And then it is to apply the thermal comfort condition to environmental design by using passive methods in Korea. Since 1920. architects have conducted studies to measure thermal comfort in houses under hot and humid conditions, while industrial hygienists have studied the effects of temperature and humidity on the performance of factory workers. Thermal comfort can be influenced by many variables. This paper conducted to review the previous researches and the human heat balance equation, and to analyse in order to reveal the meaning and usage of the thermal comfort index in two traditional essays, Fanger's PMV and Gagge's ET* Their comfort indexes compared with each other. They were based on human heat balance equation and psychological and physiological responses in the laboratory tests. The researchers and the architectural engineers using thermal comfort index shall be careful in decided the use of indexes and be necessary to recognize the value concept of the design criteria for thermal comfort. Therefore, The opinion of the authors is that different comfort standards have to apply for each building and urban with different climatic conditions.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.30 no.3
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• pp.305-312
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• 2012

This paper aims at improving the accuracy and computational efficiency in reconstructing building boundaries from airborne Lidar points. We proposed an adaptive convex hull algorithm, which is a modified version of local convex hull algorithm in three ways. The candidate points for boundary are first selected to improve efficiency depending on their local density. Second, a searching-space is adjusted adaptively, based on raw data structure, to extract boundary points more robustly. Third, distance between two points and their IDs are utilized in detecting the seed points of inner boundary to distinguish between inner yards and inner holes due to errors or occlusions. The practicability of the approach were evaluated on two urban areas where various buildings exist. The proposed method showed less shape-dissimilarity(8.5%) and proved to be two times more efficient than the other method.

• Korean Journal of Geomatics
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• v.2 no.2
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• pp.123-130
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• 2002

LiDAR (Light Detection And Ranging) system has a profound impact on geoinformatics. The laser mapping system is now recognized as being a viable system to produce the digital surface model rapidly and efficiently. Indeed the number of its applications and users has grown at a surprising rate in recent years. Interest is now focused on the reconstruction of buildings in urban areas from LiDAR data. Although with present technology objects can be extracted and reconstructed automatically using LiDAR data, the quality issue of the results is still major concern in terms of geometric accuracy. It would be enormously beneficial to the geoinformatics industry if geometrically accurate modeling of topographic surface including man-made objects could be produced automatically. The objectives of this study are to reconstruct buildings using airborne LiDAR data and to evaluate accuracy of the result. In these regards, firstly systematic errors involved with ALS (Airborne Laser Scanning) system are introduced. Secondly, the overall LiDAR data quality was estimated based on the ground check points, then classifying the laser points was performed. In this study, buildings were reconstructed from the classified as building laser point clouds. The most likely planar surfaces were estimated by the least-square method using the laser points classified as being planes. Intersecting lines of the planes were then computed and these were defined as the building boundaries. Finally, quality of the reconstructed building was evaluated.

• Journal of IKEEE
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• v.16 no.2
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• pp.95-101
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• 2012

A novel approach for the reconstruction of 3D building model from aerial image data is proposed in this paper. In this approach, a Centroid Neural Network (CNN) with a metric of line segments is proposed for connecting low-level linear structures. After the straight lines are extracted from an edge image using the CNN, rectangular boundaries are then found by using an edge-based grouping approach. In order to avoid producing unrealistic building models from grouping lined segments, a hierarchical grouping method is proposed in this paper. The proposed hierarchical grouping method is evaluated with a set of aerial image data in the experiment. The results show that the proposed method can be successfully applied for the reconstruction of 3D building model from satellite images.