• Journal of IKEEE
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• v.21 no.1
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• pp.39-45
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• 2017

Image compression is now essential for applications such as transmission and storage in data bases. For video and digital image applications the use of long tap filters, while not providing any significant coding gain, may increase the hardware complexity. We use a wavelet transform in order to obtain a set of bi-orthogonal sub-classes of images; First, the design of short kernel symmetric analysis is presented in 1-dimensional case. Second, the original image is decomposed at different scales using a subband filter banks. Third, this paper is presented a technique for obtaining 2-dimensional bi-orthogonal filters using McClellan transform. It is shown that suggested wavelet bases is well used on wavelet transform for image compression. From performance comparison of bi-orthogonal filter, we actually use filters close to ortho-normal filters on application of wavelet bases to image analysis.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.19 no.3
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• pp.219-228
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• 2001

The research into the field of managing urban utility information (such as gas pipes, power line, telecommunication utilities) is growing ever more important as the efficient management of social infra-structure gets higher and also with the fast technological progress made in nationwide scale of geo-spatial information systems. This research is focused on the collection of street utilities information in urban areas using aerial ortho-images. Until now this has been carried out by on site investigation and ground surveying methods. The result of this research shows that the geometric accuracy was obtainable within 12 cm referenced to 1/1,000 digital map. It was also possible to collect the street utilities which were described in the digital map as well as other information which were not.

• Aerospace Engineering and Technology
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• v.13 no.1
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• pp.174-183
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• 2014

The Value-Added Processing System(VAPS) was developed for post-processing the KOMPSAT imagery. Recently software version and hardware specification of VAPS were changed for improving the VAPS performance. The purpose of this study is to describe about the improvement of existing VAPS(ver.1.0) and systematically evaluate the performance of the improved VAPS(ver.2.0). To this end, test-bed areas in South and North Korea were selected and then image processing tests were conducted using KOMPSAT-2 and KOMPSAT-3 imagery in both areas. In conclusion, VAPS(ver.2.0) had an ability to generate the high level products like ortho images and mosaic images. Image processing time using the Graphic Processing Unit(GPU) on ver.2.0 was enhanced up to 10 times than ver.1.0.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.7 no.4
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• pp.355-362
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• 2017

Recently, UAV(Unmanned Aerial Vehicle) have been utilized in various fields, including surveys, mapping, and spatial analysis, depending on the increase in demand for spatial information and UAV is receiving a lot of attention due to rapid data acquisition and economic viability. In this study, the applicability of UAV image images was analyzed for urban disaster prevention. UAV images were acquired for the study area and digital surface model and ortho image were generated through data processing. Also, the process using PPK(Post Processed Kinematic) GNSS method is compared with existing method. Through the research, it was able to effectively deploy urban disaster prevention information about the target area, and displayed the effectiveness of the methods for efficient comparison with existing unmanned aerial photogrammetry. If the PPK technique is applied to thethe disaster prevention field, it is expected that the work flow in the field of rapid data acquisition and disaster prevention data construction can be greatly improved.

• Journal of Korean Society for Geospatial Information Science
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• v.18 no.4
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• pp.141-149
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• 2010

Three-dimensional geo-spatial information is important for the efficient use and management of the country and the three-dimensional expression and analysis of urban projects, such as urban plans devised by local governments and urban management. Thanks to the revitalization of the geo-spatial information service industry, it is now being variously used not only in public but also private areas. For the creation of high-guiltily three-dimensional geo-spatial information, emphasis should be placed on not only the quality of the source image and three-dimensional geo-spatial model but also the level of visualization, such as level of detail and texturing. However, in the case of existing three-dimensional geo-spatial information, its establishment process is complicated and its data are not updated frequently enough, as it uses ready-created digital maps. In addition, as it uses Ortho Images, the images exist Relief displacement. As a result, the visibility is low and the three-dimensional models of artificial features are simplified to reach LoD between 2 and 3, making the images look less realistic. Therefore, this paper, analyzed the quality of three-dimensional geo-spatial information created using the three-dimensional modeling technique were applied using Digital photogrammetry technique, using digital aerial photo images by an existing large-format digital camera and multi-looking camera. The analysis of the accuracy of visualization information of three-dimensional models showed that the source image alone, without other visualization information, secured the accuracy of 84% or more and that the establishment of three-dimensional spatial information carried out simultaneously with filming made it easier to gain the latest data. The analysis of the location accuracy of true Ortho images used in the work process showed that the location accuracy was better than the allowable horizontal position accuracy of 1:1,000 digital maps.

• Proceedings of the KIEE Conference
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• 2004.11c
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• pp.141-143
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• 2004

This paper represents 3D line segment extraction method, which can be used in generating 3D rooftop model. The core of our method is that 3D line segment is extracted by using line fitting of elevation data on 2D line coordinates of ortho-image. In order to use elevations in line fitting, the elevations should be reliable. To measure the reliability of elevation, in this paper, we employed the concept of self-consistency. We carry out the experiment of 3D line extraction using synthetic images generated from Avenches data set of Ascona aerial images.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2006.04a
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• pp.249-254
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• 2006

Aerial photo process with digital camera has some benefits. It is fast and simple by digital way in comparison with aerial photo based on film. Also it works with GPS/INS device to do direct geo-referencing, In this study, AT result from using direct exterior factors, exterior factors extracting from GPS/INS data and digital map and GCP is produced. In base on it, ortho images are produced and compared with surveying data.

• Proceedings of the KSRS Conference
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• v.2
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• pp.899-902
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• 2006

For a quick and accurate 3D modelling of a building, laser scanning data, digital maps, aerial photographs and satellite images should be fusioned. Moreover, library establishment according to a standard structure of a building and effective texturing method are required in order to determine the structure of a building. In this study, we made a standard library by categorizing Korean village forms and presented a model that can predict a structure of a building from a shape of the roof on an aerial photo image. We made an ortho image using the high-definition digital image and considerable amount of ground scanning point cloud and mapped this image. These methods enabled a more quick and accurate building modelling.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2005.10a
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• pp.300-305
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• 2005

To trace the flood inundation area around rural small stream, RADARSAT image was applied because it has the ability of acquiring data during storm period irrespective of rain and cloud. For the storm of 9 August, 1998 in Anseong-cheon watershed, three temporal RADARSAT images before, just after and after the storm were used. After ortho-rectification using 5 m DEM, two methods of RGB composition and ratio were tried and found the inundated area in the tributary stream, Seonghwan-cheon and Hakseong-cheon. The inundated area had occurred at the joint area of two streams, thus the floodwater overflowed bounding discharge capacity of the stream. The progression of damage areas were stopped by the local road and farm road along the paddy.

• Journal of Korea Water Resources Association
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• v.53 no.6
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• pp.463-467
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• 2020

The main feature of this study is to automatically synthesize square images by sending aerial photographs and images from unmanned aerial vehicles (drons). It may be applicable to the cloud server, and to apply analytical algorithms for the suitable purpose of image processing. Drone imaging analysis is a process that can be used in various fields such as finding contaminated area of green algae, monitoring forest fire, and managing crop cultivation.