• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 컴퓨터소사이어티 추계학술대회논문집
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• pp.255-258
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• 2003

This paper defines Normalized Term Frequency Weighting method for automatic text categorization by using Box-Cox, and then it applies automatic text categorization. Box-Cox transformation is statistical transformation method which makes normalized data. This paper applies that and suggests new term frequency weighting method. Because Normalized Term Frequency is different from every term compared by existing term frequency weighting method, it is general method more than fixed weighting method such as log or root. Normalized term frequency weighting method's reasonability has been proved though experiments, used 8000 newspapers divided in 4 groups, which resulted high categorization correctness in all cases.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 1997년도 Proceedings International Workshop on New Video Media Technology
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• pp.101-106
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• 1997

A method is proposed to generalize the image transformation from an image to another one according to a pair of example images. When an original image and its target image are given, the unknown image transformation from the original image to the target one in automatically approximated by a sequence of several known image transformation filters by the method. The target image is assumed to be generated manually by using a drawing software. In this method, the order of image transformation filers is regarded as the chromosome of a virtual living thing and is evolved according to Genetic Algorithm. This method can be applied to automatic construction of expert systems for image processing.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제13권8호
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• pp.3981-4004
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• 2019

This paper proposes a novel method for locating objects in real space from a single remote image and measuring actual distances between them by automatic detection and perspective transformation. The dimensions of the real space are known in advance. First, the corner points of the interested region are detected from an image using deep learning. Then, based on the corner points, the region of interest (ROI) is extracted and made proportional to real space by applying warp-perspective transformation. Finally, the objects are detected and mapped to the real-world location. Removing distortion from the image using camera calibration improves the accuracy in most of the cases. The deep learning framework Darknet is used for detection, and necessary modifications are made to integrate perspective transformation, camera calibration, un-distortion, etc. Experiments are performed with two types of cameras, one with barrel and the other with pincushion distortions. The results show that the difference between calculated distances and measured on real space with measurement tapes are very small; approximately 1 cm on an average. Furthermore, automatic corner detection allows the system to be used with any type of camera that has a fixed pose or in motion; using more points significantly enhances the accuracy of real-world mapping even without camera calibration. Perspective transformation also increases the object detection efficiency by making unified sizes of all objects.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 제14회 신호처리 합동 학술대회 논문집
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• pp.415-418
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• 2001

The automatic construction of large, high-resolution image mosaics is an active area of reasearch in the fields of photogrammetry, computer vision, image processing, and computer graphics. In this study, we describe a automatic mosaicing method that makes a panorama from images by placing camera in a emitted-grid. In the images captured by cameras, there must be a matched area and the area is in the particular area of the image. Initial transformation matrix, there(ore, is calculated from points searched in the partial area. It is possible to find best transformation matrix by Levenberg-Marquardt method. Finally, each images are multiplied by blending function and stitched by the transformation matrix to complete panoramic image.

• Journal of Welding and Joining
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• 제16권6호
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• pp.68-76
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• 1998

A CCD camera with a laser stripe was applied to realized the automatic weld seam tracking. The 3-dimensional information obtained from the vision system made it possible to generate the weld torch path. The adaptive Hough transformation was used to extract laser stripes an to obtain specific weld points. It takes relatively long time to process image on-line control using the basic control using the basic Hough transformation, but it has a tendency of robustness over the noises such as spatter. For this reason, it was complemented with adaptive Hough transformation to have an on-line processing ability for scanning specific weld points. The dead zone, where the sensing of weld line is impossible, was eliminated by rotating the camera with its rotating axis centered at the weld torch. When weld lines were detected, the camera angle was controlled in order to get the minimum image data for sensing of weld lines. Consequently, the image processing time was reduced.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1995년도 추계학술대회 논문집
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• pp.1105-1109
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• 1995

A CCD-camera, which is structured with vision system, was used to realize automatic seam-tracking system and 3-D information which is needed to generate torch path, was obtained by using laser-slip beam. To extract laser strip and obtain welding-specific point, Adaptive Hough-transformation was used. Although the basic Hough transformation takes too much time to process image on line, it has a tendency to be robust to the noises as like spatter. For that reson, it was complemented with Adaptive Hough transformation to have an on-line processing ability for scanning a welding-specific point. the dead zone,where the sensing of weld line is impossible, is eliminated by rotating the camera with its rotating axis centered at welding torch. The camera angle is controlled so as to get the minimum image data for the sensing of weld line, hence the image processing time is reduced. The fuzzy controller is adapted to control the camera angle.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 추계학술대회논문집A
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• pp.813-817
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• 2000

Cam mechanism is one of the common devices used in many automatic machinery. Specially cylindrical cam generates three dimensional motions. Thus, the shape design procedure must have high accuracy. This paper proposes the shape design procedure for a cylindrical cam and follower mechanism using a relative velocity method. The relative velocity method and coordinate transformation are used to find a contact point between cam and follower. Also, the full shape of the cylindrical cam can be generated by using the geometric relationships and the contact constraints. As a result, this paper presents an example for the sape design of the cylindrical cam in order to prove the accuracy of the design procedures.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.238-240
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• 2003

As remote sensing is weighty in GIS updating, it is indispensable to get spatial information quickly and exactly. In this study, we have designed and implemented the program by two algorithms of GDPA (Gradient Direction Profile Analysis) and Hough transformation to extract linear features automatically from high-resolution imagery. We applied the software to embody both algorithms to KOMPSAT-EOC, IKONOS, and Landsat-ETM and made a comparative study of results.

• 대한원격탐사학회지
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• 제26권1호
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• pp.39-45
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• 2010

본 연구는 지상라이다 자료의 점군간 자동정합을 위해 인접한 두 점군 자료와 함께 획득되는 2차원의 강도영상 자료로부터, 2개 영상에서 동시에 관측되는 특징점들을 이용하여 SIFT 알고리즘에 의해 공액점을 선정하였다. 또한 매칭 오류점 배제를 위해 RANSAC 알고리즘을 적용하여 정합 정확도 향상을 도모하였다. 두 점군간의 변환식 매개변수인 3차원 회전변환 각과 수직/수평 이동량을 계산, 그 결과를 기존 수작업에 의한 결과와 비교하였다. 건국대학교 이과대학 건물을 대상으로 실험한 결과, 자동매칭을 통한 변환매개변수와 수작업으로 한 변환매개변수의 차이는 X, Y, Z, 방향으로 각각 0.011m, 0.008m, 0.052m로서 자동정합 자료의 활용이 가능하다고 판단하였다.

• 한국멀티미디어학회논문지
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• 제10권10호
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• pp.1240-1250
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• 2007

본 논문은 2D 애니메이션 캐릭터의 자동 색 지정을 위하여 애니메이션 장면간의 캐릭터 색 변환 기술에 대해 제안한다. 사람이 지각하는 색은 조명이 달라지면 다른 색으로 지각된다. 이와 마찬가지로 애니메이션 장면에 등장하는 캐릭터도 의상, 피부 등의 색이 장면 분위기에 따라 각각 다르게 지정되고 있다. 본 논문은 이러한 2D 애니메이션 장면간의 캐릭터 색 지정을 수작업에 의존하지 않고 수학적으로 해결하기 위해 시도한 것으로써 조명에 따른 색 원리를 이용하여 장면간의 캐릭터 색 변환을 위한 행렬을 유도하였다. 이 색 변환행렬은 애니메이션 장면마다 각각 구해지는데, 기존의 2D 애니메이션에 등장하는 동일캐릭터의 기본색과 각 장면속의 색을 이용해서 구해진다. 이렇게 구한 색 변환행렬은 어떠한 캐릭터의 기본색만 주어진다면 다양한 장면 분위기와 잘 어울리는 색으로 변환이 가능해진다.