• Journal of Korean Tunnelling and Underground Space Association
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• v.16 no.4
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• pp.387-402
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• 2014

In congested urban areas, constructions of tunnel structures have became necessary due to a lack of surface space. The excavation of any tunnel generated the ground disturbances of surrounding ground and displacements is major concern. Therefore, a study of tunnel stability is necessary. In this study, the authors have investigated the stability and failure pattern of tunnel through the model tunnel test. In this study, the close range photogrammetry was used to measure the ground deformation. The measured data was converted to displacement vectors and contours. And then it compared to FE analysis and empirical formula. In addition, this study presented the comparison between steel pipe reinforced model tunnel and unreinforced model tunnel. The ground deformation for both the steel pipe reinforced model tunnel and the unreinforced model tunnel was analysed.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2007.04a
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• pp.99-102
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• 2007

우리나라의 교통사고발생은 OECD국가 중 인구 10만명당 사망자 14.9명으로 29개국 중 25위로 최하위권에 머물러있는 실정이다. 본 연구는 현재 적용하고 있는 우리나라 도로구조시설기준에서 정지시거에 대한 기준이 현실적이지 못하다고 분석되었기 때문에 근거리사진측량을 이용하여 3차원 모델링하고 정지시거를 명확한 근거에 기준하여 이를 규명하고자 수행하였다. 따라서 본 연구는 도로 정지시거의 기준을 재정립하여 안전하고 쾌적한 도로설계 기준을 제시하는데 그 목적이 있다.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.10 no.2
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• pp.1-12
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• 1992

This paper presents an approach for analysis of traffic accidents based on close-range Photogrammetry and Simulation of computer graphics. By using the Photographic data analysis, physical characteristics and friction factors of load, we simulated the collision form and speeds at the time of accident.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2000.10a
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• pp.40-50
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• 2000

본 연구에서는 Rolleiflex 6006 측정용 카메라로 촬영된 사진과 DCS 420 디지털 카메라로부터 촬영된 화상을 이용, 수치근접사진측량을 실시한 후, 조경석의 표면 거칠기 측정 정확도 향상을 위하여 최소제곱법으로 기준평면 또는 기준곡면을 찾아 사용하는 방법을 연구하였으며, 조경석 표면의 연마 이전과 연마 이후의 표면 거칠기를 측정, 비교하여 연마후의 거칠기 감소크기를 산출하고, 측정 정확도를 알아보기 위하여 거칠기가 거의 없는 평면인 돌과 곡면인 돌의 표면 거칠기를 측정한 결과, 그 거칠기를 기대정확도 이상인 각각 $\pm$0.lmm 및 $\pm$0.2mm의 정확도로 측정할 수 있었다. 또한 측정용 카메라인 경우 렌즈왜곡 보정에 있어서 검정자료를 토대로 기준점을 사용하지 않는 직접보정방법인 Newton-Raphson법을 적용하여 기하학적 정확도가 향상된 수치사진화상을 얻을 수 있었으며, DCS 420 디지털 카메라와 윈도우 운영체계인 Visual basic 6.0을 이용하여, 표면 거칠기 측정시스템을 구축함으로써 연마이전 조경석과 연마이후 조경석에 대한 표면 거칠기 및 형상을 정밀 측정할 수 있는 수치근접사진측량기법을 제시할 수 있었다.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.15 no.2
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• pp.185-193
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• 1997

While close range photogrammetry has been widely applied for static deformation analysis, video cameras have many characteristics that make them the sensors of choice for dynamic analysis of rapidly changing situations. They also have limitations. The aim of this research is to explore the potential of a video system for monitoring dynamic objects. A pilot system consists of two camcorders, VCR, and PC with frame grabber. To estimte the performance of this system for moving objects, a car was imaged covering several phases when starting to drive. The sequential images of a moving car were recorded on VCR. 15 images per second were digitized in an off-line mode by frame grabber. The image coordinates of targets attached to the rear bumper of a car were acquired by IDRISI, and the object coordinates were derived based on DLT. This research suggests that home video cameras, PC, and photogrammetric principles are promising tools for monitoring of the moving objects and vibrations as well as other time dependent situations.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.13 no.2
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• pp.187-198
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• 1995

An aim of this study performs effective management of cultural properties by developing digital information system which unifies dualitied management system. This study used close range photogrammetry for acquisition of digital information and designed database using GSIS to join spatial and nonspatial data. The result of this study achives the high level management and provides quickly precise data.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.9 no.2
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• pp.73-80
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• 1991

Identifying linear form of the parts of precision machine, precise monitoring is indispensable. Therefore, in this study, close-range photogrammetry being tried to screw one of the parts of precision machine, using non-metric camera that is calibrated by plumb line method. Also, it is analyzed three dimensional values of tortien, offset, section and thickness. From results of this study, monitoring of the parts of precision machine was conducted efficiently using non-metric camera and possibility of this application was proved.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.19 no.1
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• pp.47-53
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• 2001

In this study, it is intended to measure the displacement of a bridge for the safety examination using Digital Close Range Photogrammetry(DCRP). The digital images which were obtained by a digital camera and a CCD camera in load cases was analyzed. In the same condition, the displacements were obtained respectively from sensor, precision level, and film-based images for comparison. As a result, it could be confirmed that the application of DCRP to the safety examination and the movement measurement of the bridge is possible.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.7 no.2
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• pp.63-68
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• 1989

This study was to develope the methmatic prediction model of accuracy for the convergent photographs using nonmetric camera in close range photogrammetry. By analyzing positioning error on object distance and convergent angles, the validity of the new formulae for prediction of accuracy were proved. Rational design of camera systems and convergent angles according to accuracy demands in plane and height were developed using these formulae.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.28 no.6
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• pp.663-668
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• 2010

In this study a stereo digital camera system was developed. Using this system, we can collect informations such as coordinates, lengths of all objects shown in the photo image just by taking digital photograph in field. This system has the advantage of obtaining stereo images with settled exterior orientation parameters, while the accuracy slightly worsen because in a close range photogrammetry with stereo digital camera system, the base line distance is restricted within about 1m. We took images with various exposure distances and angles to objects for experimental error assessment, and analyzed the affection of image coordinates errors.