• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.33 no.1
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• pp.31-43
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• 2015

This study had been aimed to conduct the camera calibration on VLBI antenna in the Space Geodetic Observation Center of Sejong City with a low-cost digital camera, which embedded in a mobile phone to determine the three-dimension position coordinates of the VLBI antenna, based on stereo images. The initial values for the camera calibration have been obtained by utilizing the Direct Linear Transformation algorithm and the commercial digital photogrammetry system, PhotoModeler $Scanner^{(R)}$ ver. 6.0, respectively. The accuracy of camera calibration results was compared with that the camera calibration results, acquired by a bundle adjustment with nonlinear collinearity condition equation. Although two methods showed significant differences in the initial value, the final calibration demonstrated the consistent results whichever methods had been performed for obtaining the initial value. Furthermore, those three-dimensional coordinates of feature points of the VLBI antenna were respectively calculated using the camera calibration by the two methods to be compared with the reference coordinates obtained from a total station. In fact, both methods have resulted out a same standard deviation of $X=0.004{\pm}0.010m$, $Y=0.001{\pm}0.015m$, $Z=0.009{\pm}0.017m$, that of showing a high degree of accuracy in centimeters. From the result, we can conclude that a mobile phone camera opens up the way for a variety of image processing studies, such as 3D reconstruction from images captured.

• Information Systems Review
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• v.25 no.1
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• pp.1-26
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• 2023

Consumers tend to trust information provided by other consumers more than information provided by sellers. Therefore, while inducing consumers to write high-quality reviews is a very important task for companies, it is not easy to produce such high-quality reviews. Based on previous research on review writing and memory recall, we decided to develop a way to use digital nudge to help consumers naturally write high-quality reviews. Specifically, we designed an experiment to verify the effect of uploading a photo during the online review process on the quality of review of the review writer. We then recruited subjects and then divided them into groups that upload photos first and groups that do not. A task was assigned to each subject to write positive and negative reviews. As a result, it was confirmed that the behavior of uploading a photo first increases the review length. In addition, it was confirmed that when online users who upload photos first have extremely negative satisfaction with the product, the extent of two-sidedness of the review content increases.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2007.04a
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• pp.333-336
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• 2007

This paper is the environmental impact assessment of at road design in the light of the sense for the real from the virtual reality. For in this papers, This study developed 3D-model and virtual reality contents by suggesting the environmental impact assessment based on GIS in the road design. And, through this process, it's possible to visualize the environmental impact assessment by constructing the 3D-model and simulation. The 3D-model can be a method to show the road effectively by maximizing the road's shape visually after the construction. The main construction which composes polyhedron model that is generated from digital map and aerial photo is built by mapping the real texture, so the Sense for the Real was more heightened. Through this study, it must be made to shorten a long time exhausting period of conference and construct more real road after due scene consideration by specific and various low-cost strategy in the environmental impact assessment afterwards.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2007.04a
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• pp.187-190
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• 2007

This study is for analyzing best band in image matching using correlation coefficient of left and right images of stereo image pair, lot red, green, blue band images separated from color aerial photo and gray image converted from the same color aerial photo image. The image matching is applied to construct Digital Elevation Model(DEM) or terrain data. The correlation coefficients and variation by change of pixel patch size are computed from pixel patches of which sizes are $11{\times}11{\sim}101{\times}101$. Consequently, the correlation coefficient in red band image is highest. The lowest is in blue band. Therefore, to construct terrain data using image matching, the red band image is preferable. As the size of pixel patch is growing, the correlation coefficient is increasing. But increasing rate declines from $51{\times}51$ image patch size and above. It is proved that the smaller pixel patch size than $51{\times}51$ is applied to construct terrain data using image matching.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2000.10a
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• pp.638-641
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• 2000

The conventional motor in a crane has a tan generator to feed back the number of turns. The tan generator is contacted to a motor shaft through the coupling. Don has been often generated because the coupling has worn out while the motor is turning. In this paper, we design the speed-measurement device of motor in a un. The device is composed of PIC16F84 controller, photo-sensor, and analog-to digital converter. The photo sensor measures the turn of a motor without contact so the device decreases the probability of errors. And The device can acknowledge the turn direction of the motor with a gin81e senor and two color reflectors.

• Proceedings of the KIEE Conference
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• 1992.07a
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• pp.437-440
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• 1992

We design a multi-element photo-detector to measure the size of particles using the diffracted light energy distribution. The light energy that is scattered by particles in the collimated laser beam is collected by the Fourier transform lens and directed to the multi-semicircular concentric annular detecters. The scattered profile measured by the photodetector is sampled by a 32 channel analog-to-digital converter. A nonnegative least squares analysis translates the light energy distribution into the corresponding unique particle size distribution.

• Journal of the Korea Computer Graphics Society
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• v.11 no.3
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• pp.23-27
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• 2005

시간과 공간을 서로 융합하려는 노력들이 현대 화가들의 작업을 통해 여러 가지 다양한 접근 방법이 시도되고 있다. 그중 포토 꼴라주(Photo Collage)를 이용한 작업들은 컴퓨터를 이용한 영상 처리 기술과 상반된 흐름을 가지고 있어 공학적 관점에서 매우 흥미롭다. 본 논문에서는 이러한 포토 꼴라주을 한 장의 사진을 이용하여 나타내고자 한다. 이를 위해 한 장의 사진을 사각 격자로 분할하고 분할된 각 셀들을 이차원 변환(크기변환, 이동, 회전)과 톤의 조절을 통해 구현하였다.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2009.01a
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• pp.108-113
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• 2009

Significant attention has recently been drawn to digital home photo albums that use face detection technology. The tendency can be found in home photo albums that people prefer to allocate concerned objects in the center of the image rather than the boundary when they take a picture. To improve detection performance and speed that are important factors of face detection task, this paper proposes a face detection method that takes spatial context information into consideration. Experiments were performed to verify the usefulness of the proposed method and results indicate that the proposed face detection method can efficiently reduce the false positive rate as well as the runtime of face detection.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2004.11a
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• pp.239-243
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• 2004

Recently various thematic maps and image maps using aerial photograph and satellite imagery are frequently made. The geo-referencing is essential to make image map and topographic map using aerial photograph and satellite imagery. For this geo-referencing, Ground Control Points (GCPs) are needed. In this paper, we used GPS relative positioning to measure GCP ground coordinate and the accuracy of 8cm level was achieved. We made GCP image chips for the efficiency of geo-referencing and carried out the bundle adjustment of aerial photographs using GCP image chips to acquire the GCP photo coordinate with image matching technique. Finally we analyzed the accuracy of bundle adjustment compared to the accuracy of the case in using digital maps to acquire GCP photo coordinate.

• Proceedings of the Korea Information Processing Society Conference
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• 2002.11a
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• pp.23-26
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• 2002

MPV(MultiPhoto/Video)는 디지털 기기 간의 상호-연동성(Inter-operability)를 향상시키고, 사용자의 컨텐츠 관리를 용이하게 하기 위해서 제안되고 있는 표준안이다. MPV에서는 사용자의 편의를 위해서 데이터 부분에 해당하는 컨텐츠를 직접 관리하지 않고 XML 포맷으로 형성되는 메타데이터(Metadata)를 통하여 관리를 하게 되는데, MPV 와 관계 없는 소프트웨어에 의해서 컨텐츠의 정보가 변경되면, 이를 바로 잡을 수 있도록 복구 알고리즘을 제안하고 있다. 하지만. 제안된 알고리즘은 속도가 매우 느리다는 단점을 가지고 있어, 본 논문에서 이의 속도 및 효율를 향상시킬 수 있는 두 가지 알고리즘을 제안한다.