• Journal of Korean Society for Geospatial Information Science
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• v.7 no.1 s.13
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• pp.75-86
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• 1999

Three dimensional city model is composed of man-made and natural features, among these, most of man-made features are buildings. Therefore, it is very important to extract the building informations accurately and promptly to update the existing database. To achieve this, DTM can be reconstructed using building Information which is extracted from DTM, then this can be used as three dimensional city model. Thus, this paper aims to extract building boundaries and heights from high resolution DTM and edge informations of aerial photograph using mathematical morphology and image segmentation. We found that it is possible to extract buildings using opening operation in mathematical morphology and to improve the accuracy of building extraction using edge informations from aerial photograph.

• Proceedings of the KSRS Conference
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• v.1
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• pp.181-183
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• 2006

Digital topographic map in Korea contains layers of spatial and attribute data for 8 land features such as railroads, watercourses, roads, buildings and etc. Some of the layers such as building and forest don't include any information about height, which can be just prepared by interpretation of remote sensed data or field survey. LiDAR(Light Detection And Ranging) data using active pulse and digital camera provides data about height and form of land features. LiDAR data can be used not only to extract the outline of land features but also to estimate the height. This study presents technical availability for extraction and estimation of land feature's outline and height using LiDAR data which composes of natural and artificial land features, and digital aerial photograph which was taken simultaneously with the LiDAR. The estimated location, outline and height of land features were compared with the field survey data, and we could find that LiDAR data and digital aerial photograph can be a useful source for estimating the height of land features as well as extracting the outline.

• Journal of Korean Society for Geospatial Information Science
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• v.6 no.2 s.12
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• pp.45-58
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• 1998

Digital photogrammetry is growing today using inexpensive personal confuter and digital image Processing technique instead of expensive analytical plotter in data acquisition from aerial photograph. Ortho photo in replacement of paper map is indispensable in the application of Geo-Spatial Information System and research activities about it are active in the domestic domain. Also the availability of ortho photo is greatly various in existing related fields using topographic map and expected to be used for new technology in near future. For this purpose, design of each module for ortho photo has been carried out with digital map and image. It was shown that the batch program for ortho photo generation developed in this study, could be used effectively as an effective data acquisition method for GSIS.

• The Korean Journal of Ecology
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• v.24 no.4
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• pp.253-258
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• 2001

Land use pattern in the Wangsuk river watershed was investigated on the bases of physiognomic vegetation maps made from the aerial photograph interpretation and field check. Landscape structure was analyzed using a GIS program supported by ArcView. Landscape structure depended on the geographical position of the river, such as the upper, middle and lower river. Watersheds of the upper and middle rivers were dominated by forests composed of secondary forest and plantation. But agricultural fields dominated that of the middle and lower river. Urban area and agricultural fields increased in from the upper toward the lower river watersheds. In addition to, a transformation of agricultural pattern into an institutional agriculture was characteristic in the middle and lower river basins. Water qualities of the Wangsuk river were usually better in the order of the upper, middle, and lower river, but they were fluctuated according to the site. Such fluctuation would due to self-purification of the river and land use pattern of the watershed as the non-point source. In this viewpoint, a strategy to manage the water quality in the level of watershed is urgently required.

• Korean Journal of Remote Sensing
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• v.18 no.6
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• pp.327-336
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• 2002

Ever since high resolution satellites were launched, high-resolution satellite images have been utilized in many areas. This paper proposed methods of generating simulated satellite image using DEM(Digital Elevation Model) and digital image such as aerial photograph. There are two methods proposed in the paper: one is Direct-Indirect method and the other Indirect-Indirect, method. It is assumed that satellite attitude is not changing and perspective center is moving in the direction of flight while image is captured. The proposed methods were implemented with aerial photograph, DEM data, arbitrary orbit parameters and attitude parameters of high resolution satellite image under generation. Furthermore, for the stereo viewing, different orientation parameters and perspective center were tested for generating simulated satellite image. In addition, the quality and accuracy of the simulated satellite image generated by the proposed methods were analyzed.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.33 no.1
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• pp.88-96
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• 2015

This purpose of this study was to identify the landscape characteristics of cultural heritage area in Gapgot fortification by performing text analysis of related literature and antique maps. And accumulate modern photograph to investigate the landscape of modern. As a additionally analysis, was examined landscape of Gapgot fortification area using aerial photograph. The results were as follows. First, Gapgot fortification has the historical value as symbolic and practical gateway to Ganghwa island caused by geographical position. And historical culture resources were located in Gapgot fortification area such as through traffic, military facilities. Secondly, According to literature and antique maps, Gapgot fortification area was village and military facilities from Goryeo dynasty. The village and military facilities was expanded with Jinhae pavilion since construct Ganhwa castle. Thirdly, In modern Gapgot fortification area appear consecutive coastal landscape when entry Ganghwa bridge. But, inhibiting elements of landscape should be remedied.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2003.10a
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• pp.67-70
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• 2003

This study is to trace the change of stream shape using the past series of aerial photographs and compare the land use changes of inland along the stream. For the Gyeong-an national stream, aerial photographs of 1966, 1981 and 2000 was selected and ortho photograph was made with RMSE of 1.25, 0.54, 0.72 pixels, respectively. As apparent changes of the stream, the consolidated reaches of stream with levee construction were straightened and their stream width widened. Especially the stream width of inlet part of Paldang lake was widened almost twice because of the rise of water level by dam construction in 1974.

• Journal of Korean Society of Forest Science
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• v.84 no.3
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• pp.369-376
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• 1995

Black and White aerial photogrphs are much useful to obtain the information on the channel-bed fluctuation in the following aspects. 1. In the decision of river width, the linear regression formula between the value of aerial photograph interpretation and that of field surveying is Y=1.0+0.94X(the decision coefficient is $r^2=0.98$). Therefore, aerial photographs are proved effective for the measurement of river width. 2. Aerial photograph interpretation makes it possible to classify the plane channel and the deposits in river, and suggests the situation of the plane distribution of deposits, the size of channel and the course of channel formation. 3. The periodical channel situation can be figured out through the interpretation of aerial photographs pictured in different times. Also, the comparing and analyzing each interpretated information can be able to guess the course of the variation of channel influencing powerfully channel - bed fluctuation. 4. The microtopographic map of river can be made through the decision of river with, the interpretation of the plane shape of channel - bed and the analysis of variation of channel. On the basis of this map, the plane analysis of deposit is possible.

• Journal of Korean Society for Geospatial Information Science
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• v.18 no.1
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• pp.135-143
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• 2010

The national base map has its value sand roles as the basic spatial information of the nation. The current national base map that is a 1/5,000 digital map, however, has failed to perform its roles as basic spatial information due to the limitations with its quality and accuracy and requires measures to complement them. Thus this study set out to suggest ways to advance the current 1/5,000 national base map, selected topography and natural features of a digital map that could be made with GSD 0.25m digital aerial photographs, and set up the optimal ways to make a digital map by conducting an experiment of making an optimal digital map with such photographs. It also analyzed the map made with GSD 0.25m digital aerial photographs for accuracy and usability. In order to establish a set of criteria of making a digital map with GSD 0.25m digital aerial photographs, the investigator carried out analyses and picked topography and natural features items, which include 9 large categories, 31 medium categories, and 509 small categories. Then an experiment of making a digital map was conducted according to the digital map making method. As a result, solid drawing was selected as the optimal way to making a digital map, and the optimal process was established. Using the research achievements, a model digital map was made with GSD 0.25mm digital aerial photographs. The map recorded about two times horizontal and vertical location accuracy than the old 1/5,000 digital map and was capable of detailed descriptions of topography and natural features. A new national base map made with GSD 0.25m digital aerial photographs will provide reliable spatial data, thus increasing the level of satisfaction among people and the level of advancement of national base maps.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.27 no.2
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• pp.203-211
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• 2009

With supply of the domestic digital camera, the relative importance of the digital camera is coming to be high gradually on aerial photogrammetry, the image of digital camera is more applied in image map or digital topographic map production. But, there are cases that do not have position information or attitude information of each photograph in digital camera results. Therefore, we wish to present additional method to get more accurate photograph control point result. In this study, One is called A method, which is the case of entering positioning information of principal point from topographic map as default values that are need to extract tie point automatically using by 56 pieces of photography that are photographed by DMC to the extent to 5 courses and 35 GCP points. The other is called B-method, which is the case of entering exterior orientation parameters that are processed by block adjustment for A-method using by 4 control points in method-1 as default values. We have analyzed about results per control points arrangement for two cases using MATCH-AT that is photograph control point measurement S/W of Germany INPHO company. As a result of analysis, accuracy of B-method was better than that of A-method, and we could get more accurate results if block adjustments are executed including self calibration. Also, it is more effective in expense side that using self calibration for photograph survey in B-method because can reduce GCP numbers.