• Journal of Conservation Science
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• v.25 no.4
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• pp.363-371
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• 2009

This study is purposed to investigate that current rubbing technique could be replaced by the photographic rubbing techniques with the photographic lighting and digital techniques. The lighting technique is based on the "texture description theory" using the electric flash and the intaglio epitaph was emphasized from the observation of the both side because it is purposed to decipher epitaph. The photographs were retouched using the photoshop to emphasize epitaph and the spots from the lichen on the tombstone were softened. Especially, it shows that faint epitaph could be deciphered if the digital techniques could be used practically even though some part of the epitaph was destroyed or peeled. Furthermore, it will help to investigate, protect and restore the cultural properties because it surely makes the recording of the material, weathering, peeling of the tombstone much easier than the current rubbing technique.

• Journal of Korean Society for Geospatial Information Science
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• v.18 no.4
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• pp.41-50
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• 2010

Because mountain area covers a large proportion of entire country, the forest fire have been an important matter in disaster prevention in Korea. Estimation of damaged area after forest fire would be very important because it would be the basis to make budget or to calculate quantities in the restoration plan for the damaged area. In Korea, the damaged area from forest fire is generally surveyed using GPS. In practice, however, the estimation of damaged area from forest fire have been inaccurate in lots of case due to some problems. Korea Forest Service which is taking charge of prevention of forest fire in Korea is managing a large number of helicopters for forest service on the whole country. So, it would be possible to take snapshots of the damaged area after forest fire from the helicopter using a digital camera. This study aims to establish a suitable method to estimate damaged area after forest fire using snapshots which are taken in the air using a digital camera. So, several approaches were implemented and compared. In future, results of this study could be used in a development of a system for investigation of damages from forest fire using digital photographs.

• The Journal of the Korean dental association
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• v.43 no.10 s.437
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• pp.662-671
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• 2005

• 대한방사선방어학회:학술대회논문집
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• 2011.04a
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• pp.132-133
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• 2011

• Proceedings of the Optical Society of Korea Conference
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• 2007.07a
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• pp.69-70
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• 2007

• The Optical Journal
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• s.126
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• pp.34-38
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• 2010

최근 할리우드를 중심으로 디지털 3D 시네마가 일반화되고 있으며, 삼성, LG를 비롯한 국내외 기업들이 적극적으로 3D 시장에 뛰어들기 시작했다. 3D는 단순히 영상분야 뿐만이 아닌 전 분야에 걸쳐 파급효과가 있는 융합형 IT 산업임에 틀림없다. 본 고에서는 이러한 3D 영상 촬영을 위한 장비 기술과 업체 현황에 대해 소개하고자 한다.

• Progress in Medical Physics
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• v.22 no.4
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• pp.184-189
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• 2011

The purpose of this study was to compare the image between DSA and MDCT Angiography and to examine whether MDCT Angiography could be useful as a screening test for the diagnosis of cerebral aneurysm in patients who were diagnosed with cerebral aneurysm on DSA. Of patients who were diagnosed with cerebral aneurysm DSA at University Hospital, 194 patients who concomitantly underwent MDCT Angiography were enrolled in the current retrospective study. The methods for analyzing cerebral aneurysm were to analyze the presence of cerebral aneurysm on DSA and MDCT Angiography. In cases in which it exceeded 1, the corresponding cases were classified as narrow-neck aneurysms. In otherwise cases, they were classified as wide-neck aneurysms. Thus, a comparative analysis could be performed to ascertain if cases were narrow-neck or wide-neck aneurysms. As compared with DSA, the sensitivity of MDCT Angiography for cerebral aneurysm was measured to be 97.4%. The degree of consistency between narrow-neck and wide-neck aneurysms was 90.2% and the proportion of undetectable an at MDCT Angiography was 2.54%. mean size was 2.4 mm. It is expected that a non-invasive diagnostic modality for a screening test for cerebral aneurysm, MDCT Angiography might be a very useful regimen as compared with an invasive one, DSA.

• Journal of radiological science and technology
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• v.38 no.3
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• pp.221-228
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• 2015

Purpose: In digital mammography QC program was used for the purpose of reducing low-dose and high-definition images of the radiation dose. Materials and Methods: In digital mammography using a QC phantom according to the average glandular dose in the exposure method MLO view $0^{\circ}C$, $30^{\circ}C$, $45^{\circ}C$, $50^{\circ}C$, $55^{\circ}C$, $70^{\circ}C$, was measured at $90^{\circ}C$ intervals, an image with Hologic QC program to the SNR and CNR was measured to evaluate. Results: The average dose in the MLO view was wired to $90^{\circ}C$ when the maximum was 1.75 mGy, it decreased approximately 6% was measured at $45^{\circ}C$ 1.65 mGy. In addition, 1.67 mGy, manual record, there were an average wired in accordance with the exposure dose and the dose of 1.52 mGy difference in the way auto filter. Image quality evaluation at every angular section SNR 50 ~ 52, shows a slight difference in CNR 11 ~ 12, it was included in the manufacturer's recommended value. Conclusion: The dose was lowest in MLO view $45^{\circ}C$, the difference between SNR and CNR were insignificant. The method of exposure will need a way to reduce the exposure of the patient's body or unnecessary patient by placing a difference in settings in which the characteristics.

• Journal of the Korean Society of Radiology
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• v.12 no.5
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• pp.645-650
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• 2018

This research aims at measuring images density of according to DAP(dose area product), and suggesting the need to quality control of exposure dose. When tube voltage was fixed as 80 kVp and tube current was set as 1, 25, 50, 80, and 100 mAs, with the increase of DAP from 25 mAs to 50 mAs, the dose also rose 1.88 times as much as before, and with the increase from 50 mAs to 100 mAs, it got 2.05 time higher than before. However, the images density obtained as film grew as much as 48% with the increase from 25 mAs to 50 mAs, and 29% with the increase from 50 mAs to 100 mAs. In addition, it has been found out that the higher the DR images density got from 25 mAs to 50 mAs, the bigger it became by 12%, and that it got bigger by 30% with the increase from 50 mAs to 100 mAs. In other words, the differences in the image density by the increase of the dose with the digital imaging equipment in a proper condition was proved to be less than in the film images. Based on the results of this research, medical institutions using a digital imaging equipment are expected to be able to reduce exposure dose of each region of interest than now through the quality control of radiation dose.

• Journal of Cadastre & Land InformatiX
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• v.52 no.1
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• pp.69-80
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• 2022

Drone photogrammetry generally acquires images vertically or obliquely from above, so when photographing for the purpose of three-dimensional modeling, image matching for the ground of a building and spatial accuracy of point cloud data are poor, resulting in poor 3D mesh completeness. Therefore, to overcome this, this study analyzed the spatial accuracy of each drone image by acquiring smartphone images from the ground, and evaluated the accuracy improvement and completeness of 3D mesh when the smartphone image is not combined with the drone image. As a result of the study, the horizontal (x,y) accuracy of drone photogrammetry was about 1/200,000, similar to that of traditional photogrammetry. In addition, it was analyzed that the accuracy according to the photographing method was more affected by the photographing angle of the object than the increase in the number of photos. In the case of the smartphone image combination, the accuracy was not significantly affected, but the completeness of the 3D mesh was able to obtain a 3D mesh of about LoD3 that satisfies the digital twin city standard. Therefore, it is judged that it can be sufficiently used to build a 3D model for digital twin city by combining drone images and smartphones or DSLR images taken on the ground.