• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.37 no.6
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• pp.427-434
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• 2019

In the present study, we assessed the parallel computing performance of Agisoft Metashape for orthomosaic generation, which can implement aerial triangulation, generate a three-dimensional point cloud, and make an orthomosaic based on SfM (Structure from Motion) technology. Due to the nature of SfM, most of the time is spent on Align photos, which runs as a relative orientation, and Build dense cloud, which generates a three-dimensional point cloud. Metashape can parallelize the two processes by using multi-cores of CPU (Central Processing Unit) and GPU (Graphics Processing Unit). An orthomosaic was created from large UAV (Unmanned Aerial Vehicle) images by six conditions combined by three parallel methods (CPU only, GPU only, and CPU + GPU) and two operating systems (Windows and Linux). To assess the consistency of the results of the conditions, RMSE (Root Mean Square Error) of aerial triangulation was measured using ground control points which were automatically detected on the images without human intervention. The results of orthomosaic generation from 521 UAV images of 42.2 million pixels showed that the combination of CPU and GPU showed the best performance using the present system, and Linux showed better performance than Windows in all conditions. However, the RMSE values of aerial triangulation revealed a slight difference within an error range among the combinations. Therefore, Metashape seems to leave things to be desired so that the consistency is obtained regardless of parallel methods and operating systems.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.53 no.4
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• pp.277-285
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• 2004

We present a new hybrid stereo matching technique in terms of the co-operation of area-based stereo and feature-based stereo. The core of our technique is that feature matching is carried out by the reference of the disparity evaluated by area-based stereo. Since the reference of the disparity can significantly reduce the number of feature matching combinations, feature matching error can be drastically minimized. One requirement of the disparity to be referenced is that it should be reliable to be used in feature matching. To measure the reliability of the disparity, in this paper, we employ the self-consistency of the disunity Our suggested technique is applied to the detection of 3D line segments by 2D line matching using our hybrid stereo matching, which can be efficiently utilized in the generation of the rooftop model from urban imagery. We carry out the experiments on our hybrid stereo matching scheme. We generate synthetic images by photo-realistic simulation on Avenches data set of Ascona aerial images. Experimental results indicate that the extracted 3D line segments have an average error of 0.5m and verify our proposed scheme. In order to apply our method to the generation of 3D model in urban imagery, we carry out Preliminary experiments for rooftop generation. Since occlusions are occurred around the outlines of buildings, we experimentally suggested multi-image hybrid stereo system, based on the fusion of 3D line segments. In terms of the simple domain-specific 3D grouping scheme, we notice that an accurate 3D rooftop model can be generated. In this context, we expect that an extended 3D grouping scheme using our hybrid technique can be efficiently applied to the construction of 3D models with more general types of building rooftops.

• Korean Institute of Interior Design Journal
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• v.22 no.5
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• pp.42-50
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• 2013

The upscale Korean restaurants that appeared as a way for the globalization of Korean food by introducing Western modern elements into Korean traditional elements are presenting a new direction. For this study, the researcher visited a total of ten modernized upscale Korean restaurants including five ones in each of Seoul (Dadam, Bistro Seoul, Bicena, Today, and Poom Seoul) and New York (Gaonnuri, Danji, Ban, Jung Restaurant, Korea Spoon), where the globalization of Korean food is concentrated, and the results of comparing, investigating, and analyzing the characteristics of interior and spatial design through observation, photo taking, sketches and preparing a questionnaire were as follows. First, a modernized upscale Korean restaurant was first built in New York in 2011, and then also appeared in Seoul in 2012. The Korean restaurants in New York were mostly operated by individual person, while the Korean restaurants in Seoul were operated by large corporation. Second, the spatial configuration elements were classified into the reception, garden and rooms in Seoul and into the reception, bar hall and rooms in New York depending on the function of the interior space, showing differences in the spatial configuration elements of the garden and bar. There was a difference in spatial layout; the restaurants in Seoul were room-centered, while the ones in New York were hall-centered. Third, in terms of spatial design elements, the size of the space and furniture in the reception space of the Korean restaurants in New York were smaller as compare to those in Seoul, while the restaurants in New York represented Korean atmosphere by decorating many Korean traditional elements. The Korean restaurants in New York gave consistency to the design of the hall space as compared to the restaurants in Seoul by decorating interior decorative accessories associated with the restaurant name. The Korean restaurants in Seoul decorated room space by using more traditional elements as compared to the restaurants in New York. Fourth, in terms of food design elements, the restaurants in Seoul are characterized by the introduction of Western services and table setting, while the restaurants in New York sought originality that applied foreign ways as compared to the restaurants in Seoul. The results of this study can be used as useful basic data when setting the interior spatial design guidelines for the modernized upscale Korean restaurants that advance into the world beyond Seoul and New York, and it is expected that in-depth follow-up studies would be conducted in various cities beyond Seoul and New York where there are modernized upscale Korean restaurants based on the results of this study.