• Journal of the Speleological Society of Korea
• /
• no.64
• /
• pp.61-80
• /
• 2004

This book deals with a .gesture of photography as a Political phenomena. In the gesture of photography, the conceptions that influences the cause and the policy of solutions that conflict the cultures, are developed. The contents of this book contains lots of items, and efforts to find the root of the digital revolution of nowadays.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
• /
• 2004.11a
• /
• pp.245-249
• /
• 2004

최근에는 항측기에 GPS/INS 장비를 탑재하여 사진의 촬영과 동시에 외부표정요소를 직접 결정할 수 있는 Direct Georeferencing 기술의 개발로 인하여 지상기준점측량과 AT과정이 불필요하게 되었다. Direct Georeferencing 기법을 이용하게 되면 외부표정요소를 구하기 위한 전처리 과정을 생략할 수 있다. 따라서 지상기준점을 이용한 사진기 준점측량(AT)을 수행하지 않더라도 수치표고모델만 미리 확보되어 있으면 촬영과 동시에 수치정사사진을 생성할 수 있다. 본 연구에서는 촬영과 동시에 GPS/INS에 의해 획득한 외부표정요소와 항공사진을 이용하여 영상매칭에 의하여 수치표고모델(DEM)을 자동 생성하고, 이 결과를 바탕으로 정사사진을 제작하였다. 실제 도화데이터와 Direct Georeferencing 정사영상과의 오차를 평가한 결과, 표준편차가 X는 약 62cm, Y는 약 76cm 정도가 발생하였다. 이 결과는 축적 1：5,000 수치지도의 정확도 요구를 충분히 만족시킬 수 있는 양호한 결과임을 알 수 있다. Direct Georeferencing에 의한 정사영상의 제작방법은 큰 크기의 과대오차가 발생하는 부분을 수작업 또는 반자동으로 해결할 수 있으면 효율적으로 수치지도를 수정/갱신 할 수 있을 것으로 판단된다.

• Smart Media Journal
• /
• v.11 no.2
• /
• pp.25-30
• /
• 2022

With the recent development of device performance such as smartphones, cameras, and video cameras, it has become possible to obtain human biometric information from images and photos. A German hacker group obtained human iris information from high-definition photos and revealed hacking into iris scanners on smartphones. As high-quality images and photos can be obtained with such advanced devices, the need for a suitable security system is also emerging. Therefore, in this paper, we propose a method of automatically masking human iris information in images and photos using Haar Cascades and Blur models from openCV. It is a technology that automatically masks iris information by recognizing a person's eye in a photo or video and provides the result. If this technology is used in devices and applications such as smartphones and zoom, it is expected to provide better security services to users.

• Tunnel and Underground Space
• /
• v.13 no.5
• /
• pp.373-388
• /
• 2003

The investigation on the rock discontinuity geometry has been usually undergone by direct measurement on the rock exposures. But this sort of field work has disadvantages, which we, for example, restriction of surveying areas and consuming excessive times and labors. To cover these kinds of disadvantages, image processing could be regarded as an altemative way, with additional advantages such as automatic and objective tools when used under adequate computerized algorithm. This study was focused on the recognition of the rock discontinuities captured in the image of rock exposure by digital camera and the production of the discontinuity map automatically. The whole process was written using macro commands builtin image analyzer, ImagePro Plus. ver 4.1(Media Cybernetic). The procedure of image processing developed in this research could be divided with three steps, which are enhancement, recognition and extraction of discontinuity traces from the digital image. Enhancement contains combining and applying several filters to remove and relieve various types of noises from the image of rock surface. For the next step, recognition of discontinuity traces was executed. It used local topographic features characterized by the differences of gray scales between discontinuity and rock. Such segments of discontinuity traces extracted from the image were reformulated using an algorithm of computer decision-making criteria and linked to form complete discontinuity traces. To verify the image processing algorithms and their sequences developed in this research, discontinuity traces digitally photographed on the rock slope were analyzed. The result showed about 75～80% of discontinuities could be detected. It is thought to be necessary that the algorithms and computer codes developed in this research need to be advanced further especially in combining digital filters to produce images to be more acceptable for extraction of discontinuity traces and setting seed pixels automatically when linking trace segments to make a complete discontinuity trace.

• Journal of the Korean Society of Radiology
• /
• v.17 no.3
• /
• pp.433-440
• /
• 2023

High dose rate brachytherapy is a cancer treatment that intensively irradiates radiation to tumors by inserting isotopes with high dose rates into the body. For such a treatment, it is necessary to deliver an accurate dose to the tumor tissue through an accurate treatment plan while delivering only a minimum dose to the normal tissue. Therefore, it is very important to check the location accuracy of the source through accurate Quality Assurance (QA) in clinical practice. However, since the source position is determined using a ruler, automatic radiographer, video monitor, etc. in clinical practice, it yields inaccurate results. In this study, a semiconductor dosimeter using CsPbI₂Br and CsPbIBr₂ was fabricated. And, in order to analyze whether it is more suitable for the relative QA dosimeter for brachytherapy device among the two materials, the radiation detection ability of each was compared and evaluated. In order to evaluate the radiation detection ability in brachytherapy, the reproducibility and linearity of the two materials were evaluated in ¹⁹²IR. In the reproducibility evaluation, CsPbI₂Br presented a Relative Standard Deviatio(RSD) of 0.98% and CsPbIBr₂ presented an RSD of 3.45%. In the linearity evaluation, the coefficient of determination (R²) of CsPbI₂Br was presented as 0.9998, and the R² of CsPbIBr₂ was presented as 0.9994. As a result of the evaluation, it was found that CsPbI₂Br was more stable in radiation detection while satisfying the evaluation criteria in the dosimeter manufactured in this experiment. Therefore, CsPbI₂Br material is suitable for application as a relative dosimeter for radiation detection in brachytherapy devices.