• Journal of the Korean Association of Geographic Information Studies
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• v.19 no.4
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• pp.169-185
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• 2016

Recently mean stand height has been added as new attribute to forest type maps, but it is often too costly and time consuming to manually measure 9,100,000 points from countrywide stereo aerial photos. In addition, tree heights are frequently measured around tombs and forest edges, which are poor representations of the interior tree stand. This work proposes an estimation of mean stand height using an image-based point cloud, which was extracted from stereo aerial photo with FUSION S/W. Then, a digital terrain model was created by filtering the DSM point cloud and subtracting the DTM from DSM, resulting in nDSM, which represents object heights (buildings, trees, etc.). The RMSE was calculated to compare differences in tree heights between those observed and extracted from the nDSM. The resulting RMSE of average total plot height was 0.96 m. Individual tree heights of the whole study site area were extracted using the USDA Forest Service's FUSION S/W. Finally, mean stand height was produced by averaging individual tree heights in a stand polygon of the forest type map. In order to automate the mean stand height extraction using photogrammetric methods, a module was developed as an ArcGIS add-in toolbox.

• The Journal of the Korea Contents Association
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• v.15 no.8
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• pp.389-396
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• 2015

The liver fibrosis is a disease we often see in clinical medicine, and the persistence and repeatition of inflammation and necrosis of liver cells continue for several years, and it is proceeded to cirrhosis. So decrease of death rate and prevalence rate by complications of cirrhosis and hepatocellular carcinoma is main task of clinical medicine by protection of chronic liver ailment patients from proceeding to cirrhosis and hepatocellular carcinoma. So this study tried to represent the ultrasonic image, blood test, the relationship with liver stiffness of diffuse liver ailment patients as numbers. This study was performed with patients from whom the image was taken by ultrasonic and 141 people who were treated by fibroscan, the basic data for blood test was obtained from the test results at the time when ultrasonic image and liver fibroscan was performed. The statistical analysis was performed by One-way analysis of variance(ANOVA) to verify difference between groups. The value of liver stiffness was increased in the order of normal, chronic liver disease and cirrhosis. As a results, ALT and Albumin have no statistical difference between object groups, and there are statistical differences in the results of ultrasonic decoding at age, AST, ALP, Bilirubin, PLT, PT, and kPa, and they are statistically meaningful(p<0.005). And the value of liver stiffness of chronic liver ailment was presented only as over 12.5kPa in other study, but it was represented as numbers for quantitative diagnosis by presenting average kPa threshold value according to disease in this study. And by presenting relationship of diagnosed results, it is considered that it could be used as first tool to diagnose chronic liver ailment patients according to their disease.

• Journal of the Korean Association of Geographic Information Studies
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• v.15 no.1
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• pp.197-210
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• 2012

The KOrea Multi-Purpose SATellite(KOMPSAT)-2 has a capability to provide a cross-track stereo imagery using two different orbits for generating various spatial information. However, in order to fully realize the potential of the KOMPSAT-2 stereo imagery in terms of mapping, various tests are necessary. The purpose of this study is to evaluate the possibility of mapping using the KOMPSAT-2 stereo imagery. For this, digital plotting was conducted based on the stereoscopic images. Also the Digital Elevation Model(DEM) and an ortho-image were generated using digital plotting results. An accuracy of digital plotting, DEM, and ortho-image were evaluated by comparing with the existing data. Consequently, we found that horizontal and vertical error of the modeling results based on the Rational Polynomial Coefficient(RPC) was less than 1.5 meters compared with the Global Positioning System(GPS) survey results. The maximum difference of vertical direction between the plotted results in this study and the existing digital map on the scale of 1/5,000 was more than 5 meters according as the topographical characteristics. Although there were some irregular parallax on the images, we realized that it was possible to interpret and plot at least seventy percent of the layer which was required the digital map on the scale of 1/5,000. Also an accuracy of DEM, which was generated based on the digital plotting, was compared with the existing LiDAR DEM. We found that the ortho-images, which were generated using the extracted DEM in this study, sufficiently satisfied with the requirement of the geometric accuracy for an ortho-image map on the scale of 1/5,000.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.18 no.4
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• pp.395-403
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• 2000

It is so sensitive that the matter of compensation for private possessions caused in the course of public construction planning is very important. Especially, more logical planning is necessary when the dam be constructed, because it is mainly controlled by the surface of water, and if that planning is made public, artificial change is occurred in land use in that area for the purpose of rising the compensation. In this study, the plan for the application of aerial photo based ortho image was drew up for solving these problems and for the rational, rapid compensation. Ortho image was made by aerial photo, used as reading material for the change in land use. The modeling of drainage basin, came under the planning surface of water, and the 3D simulation were performed for the scene analysis, the change understanding in land use for a lot number in a certain period by overlapping the digital image, the digital land registration map, and the digital topography map as well as the analysis of the admitted land followed by the height of reservoir water.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.36 no.6
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• pp.483-497
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• 2018

Image mosaicking, which combines several images into one image, is effective for analyzing images and important in various fields of spatial information such as a continuous image map. The crucial processes of the image mosaicking are optimal seamline determination and color correction of mosaicked images. In this study, the overlap regions were determined by SURF (Speeded Up Robust Features) for image matching. Based on the characteristics of the edges extracted by Canny filter, seamline candidates were selected from classified edges with their characteristics, and the edges were connected by using Dijkstra algorithm. In particular, anisotropic filter and image pyramid were applied to extract reliable seamlines. In addition, it was possible to determine seamlines effectively and efficiently by utilizing building and road layers from digital maps. Finally, histogram matching and seamline feathering were performed to improve visual quality of the mosaicked images.

• Journal of the Korean Geotechnical Society
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• v.37 no.9
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• pp.13-24
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• 2021

Recently, attempts have been made to detect fouling patterns in the ground using Ground Penetrating Radar (GPR) during the maintenance of gravel ballast railway tracks. However, dealing with GPR signal data obtained with a large amount of noise in a site where complex ground conditions are mixed, often depends on the experience of experts, and there are many difficulties in precise analysis. Therefore, in this study, a numerical modeling technique that can quantitatively simulate the GPR signal characteristics according to the degree of fouling of the gravel ballast material was proposed using python-based open-source code gprMax and RSA (Random sequential Absorption) algorithm. To confirm the accuracy of the simulation model, model tests were manufactured and the results were compared to each other. In addition, the identification of the fouling layer in the model test and analysis by various test conditions was evaluated and the results were analyzed.

• Journal of the Korean earth science society
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• v.25 no.8
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• pp.799-811
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• 2004

In this one species of planktonic foraminifers, Neogloboquadrina pachyderma, which has been collected from the sediments cores in the northeast Pacific ODP sites, was computerized through using digitalized images. The foraminiferal communities were analyzed, and the coiling direction of the N. pachyderma was determined by using computer progamming technology. In this way by appling algorithm-based method of reading, the tasks of sorting and analyzing the foraminiferal indiniduals and communities can be performad and high speed on a very large amount of specimens collected. It is found that the study had 90% accordance with the result of stereoscopic observation. This result suggested that digital image analysis could be successfully adopted in the field of micropaleontology.

• Journal of Korea Spatial Information System Society
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• v.4 no.2 s.8
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• pp.35-40
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• 2002

In this study we developed a CCD camera image capture program for Mobile Mapping System. Especially, two high resolution color images could be captured and saved simultaneously through this program to apply digital photogrammetry. Program developed in this study could be used more effectively on the 3D positioning of road facilities, the state understanding of maintenance and etc. using Mobile Mapping System with GPS-IMU. Most programs currently developed and used are for the panchromatic images. But, newly developed program is for the high resolution color images. Therefore newly developed program could expand application field of Mobile Mapping System widely, and users. This research can improve the usability of 4S' products with stable and reliable.

• Journal of the Korean Society of Radiology
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• v.16 no.3
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• pp.265-271
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• 2022

This study retrospectively analyzed the test results of 441 patients who visited Hospital I in Busan from October 2021 to December 2021 and conducted both mid-term ultrasound and fibroscan tests. The purpose of the study was to investigate the usefulness of fibroscan in inter-fat evaluation by conducting correlation analysis and chi-squared test of inter-fat evaluation using liver ultrasound and fibroscan. As a result of analyzing the correlation between the fatty liver reading result of abdominal ultrasound and Fibroscan UAP, the correlation was found to be r=0.600 and p=0.000. In the inter-provincial evaluation, Fibroscan showed high validity in predicting objective results using inter-provincial values.

• Economic and Environmental Geology
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• v.51 no.2
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• pp.167-176
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• 2018

It is necessary to consider various geological parameters such as lithology, geological structure, earthquake, hydraulic geology, geochemistry, geological engineering, and geothermal in order to select potential sites for HLW(high-level radioactive waste) geological disposal. In particular, the geological lineament reflects the characteristics of various geological parameters and can be used as an important criterion for site selecting such as nuclear power plants and HLW repositories. In this paper, the Finnish lineament classification method for HLW disposal site selection through the lineament analysis was applied to the lineament data in the Korean peninsula. For this purpose, we used previous lineament data from the KIGAM(Korea Institute of Geoscience and Mineral Resources) and obtained new lineament data from the field geologists such as structural geologist, paleoseismologist, and geomorphologist. To ensure the reliability of the new lineament analysis data, we used high-resolution satellite images and hill-shade relief maps which were constructed by a digital elevation model. In the prevailing direction analysis from the acquired lineament data, the NNE-SSW direction was the most dominant, but the ENE-WSW and NNW-SSE directions also showed highly frequency depending on the experts. Applying the Finnish classification method, the geometrical development characteristics of the lineament corresponding to the Class 1 and 2 used for the wide-wide candidate site were compared. As a result of direction analysis for Class 1, the NNE-SSW direction was the most dominant and the WNW-ESE direction also showed a high frequency. In the case of Class 2, the NNE-SSW is the most prevalent and WNW-ESE or ENE-WSW direction also had highly frequency depending on the experts. Different lineament analysis results based on the same data are interpreted as a result of subjective experience and analytical criteria from the every experts. Therefore, it is necessary to establish integrated criteria and consider geophysical data for the publication of reliable nation-wide lineament map.