• 한국산학기술학회논문지
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• 제20권8호
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• pp.1-7
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• 2019

최근 3D 이미지 스캔(image scan) 작업을 통해 획득한 3D 포인트 클라우드(point cloud)를 활용하는 사례가 점차 많아지고 있다. 특히, 도시나 건물 차원의 실내/실외, 기계 플랜트 등 3D 공간정보 콘텐츠를 활용한 서비스 개발 필요성이 증가하면서, 3D 이미지 스캔 기술의 수요가 급격히 늘고 있다. 기존의 3D 이미지 스캔 방법을 사용하는 경우, 이미지 스캔 작업은 노동집약적인 수작업으로 진행되는 것이 일반적이다. 따라서, 사용자가 복잡한 설비로 이루어진 공간을 스캐닝 할 때나, 사용자가 내부로 진입하기 어려운 좁은 공간을 스캐닝하기에는 어려움이 있으며, 결과적으로 그림자 영역 문제로 인한 품질 저하 문제를 발생시킨다. 본 연구는 사람이 진입하기 어려운 영역에 스캐너가 장착된 로버를 활용해 이미지 스캔을 하는 방법을 제안한다. 스캔 경로를 정확히 제어하기 위해, 로버 이동 규칙 정의 기반 3D 이미지 원격 스캔 자동화 방법을 기술한다. 이 방법을 통해, 사용자는 로버의 스캔 경로를 규칙 기반으로 정의함으로써 3D 스캔 계획을 자동화할 수 있다.

• 대한의용생체공학회:의공학회지
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• 제17권4호
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• pp.469-478
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• 1996

In the conventional digital ultrasound scanner, the reflected signal is sampled either in polar coordinates of R-$\theta$ method, or in Cartesian coordinates of uniform ladder algorithm (ULA). The R-$\theta$ scan method necessitates a coordinate transform process which makes hardware complex in comparison with ULA scan mrthoA In spite of this complexity, R-$\theta$ method has a good resolution in ultrasonographic (US) image, since scan direction of the US imaging is a radial direction. In this paper, a new digital scan converter is proposed, which is named the radius uniform ladder algorithm (RULA). The RULA has the rome scan direction as the US scanning in the radial direction and as the display space in the $\theta$ direction. In tllis new approach, sampled points we uniformly distributed in each horizontal line i.n well as in each radial ray so that the data are displayed in the Cartesian coordinates by the 1-D interpolation process. The propped algorithm has an uniform resolution in the periphery and the center field in comparison with equi-angle ULA and equi-interval ULA. To extend the scan angle, concentric square raster sampling (CSRS) is adopted with reduction of discontinuities on the junctions between horizontal scan and vertical scan. The discontinuities are reduced by using the hmction filtering along the $\theta$ direction.

• Current Optics and Photonics
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• 제6권3호
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• pp.304-312
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• 2022

Digital images of cultural relics captured using line scan cameras present limitations due to uneven intensity and low contrast. To address this issue, this report proposes a colour linear array image enhancement method that can maintain a constant colour. First, the colour linear array image is converted from the red-green-blue (RGB) colour space into the hue-saturation-intensity colour space, and the three components of hue, saturation, and intensity are separated. Subsequently, the hue and saturation components are held constant while the intensity component is processed using the established intensity compensation model to eliminate the uneven intensity of the image. On this basis, the contrast of the intensity component is enhanced using an improved local contrast enhancement method. Finally, the processed image is converted into the RGB colour space. The experimental results indicate that the proposed method can significantly improve the visual effect of colour linear array images. Moreover, the objective quality evaluation parameters are improved compared to those determined using existing methods.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1996년도 추계학술대회
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• pp.157-160
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• 1996

In this paper, reconstruction algorithms of spiral scan imaging which has been used for ultra fast magnetic resonance imaging have been reviewed, and some simulation results using two different algorithms are reported. Since the trajectory of the spiral scan in k-space is the spiral, reconstruction of the spiral scan is not as straight forward as that used in Fourier imaging technique where the sampling points are usually on the rectangular grids. Originally the reconstruction of the spiral scan imaging was based on the convolution backprojection algorithm modified with a shift term, however, some other reconstruction techniques have also been tried by remapping sampling points from spiral trajectory to Cartesian grids. Some experimental aspects of MR spiral scan imaging will also be addressed.

• 한국BIM학회 논문집
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• 제12권3호
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• pp.39-51
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• 2022

3D scan technology can utilize real spatial information as it is in virtual space, so it can be usefully used in various fields such as reverse engineering of buildings and process management. Recently, with the development of ICT technology, more precise scan data can be obtained, and scan processing time has also been greatly reduced. In addition, the combination of software and scanning equipment used in 3D scanning technology is very diverse, and results are very different depending on which technology is used. Accordingly, there is a problem that it is difficult for a user who has no experience in 3D scanning technology to determine which technology and equipment should be used to obtain good results. In this study, 3D scan technologies mainly used at home and abroad are investigated, classified, and tested at actual construction sites to suggest considerations and suitable 3D scan methods when using 3D scans in construction sites. The test results were analyzed to evaluate the time it takes to scan, the final quality, and the user's convenience according to each technology method.

• 대한족부족관절학회지
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• 제11권1호
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• pp.8-12
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• 2007

Purpose: The purpose of this study was to investigate the differences in simple radiographic parameters and results of 3-D scan among normal and patient groups. Materials and Methods: Seventy subjects in each group were studied. Control group consisted of subjects without plantar foot pain (normal group), and two patient groups were one with plantar forefoot pain (metatarsalgia group), the other with plantar heel pain (heel pain group). Simple radiographic parameters were obtained and 3-D scan was done with foot scanner (Nexscan, K&I, Korea) and The height and volumn of the space under the medial longitudinal arch was analyzed (Enfoot, K&I, Korea). These parameters were compared and correlation between radiological parameters and results of the 3-D scan were studied. Results: The results of all parameters istributed normally. There was no signigicant differences among the groups in radiological parameters (talo-first metatarsal angle, calcaneal pitch angle and height of the talar head in standing lateral radiograph) and arch height and arch volumn on 3-D scan. There were statistically significant correlations between radiological and 3-D scan results. Conclusion: This study revealed that there is no significant differences in medial longitudinal arch height and volumn among normal and different patient groups and there are variety of arch height in patients with similar symptoms.

• Imaging Science in Dentistry
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• 제51권1호
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• pp.87-90
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• 2021

The increased use of cone-beam computed tomographic (CBCT) scans has made it increasingly necessary to evaluate incidental findings on CBCT scans. This report describes the case of a 66-year-old female patient who presented to the Department of Oral and Maxillofacial Pathology, Radiology and Medicine at the College of Dentistry of the author's institution and underwent a CBCT scan for maxillary alveolar process implant planning. Upon evaluation of the CBCT scan, a radiopaque (soft tissue attenuation) mass in the left superior aspect of the nasal cavity and left locule of the sphenoid sinus with opacification of the left locule of the sphenoid sinus was incidentally noted. These radiographic findings were suggestive of a space-occupying mass with a high possibility of malignancy. A further medical evaluation confirmed renal cell cancer metastasis to the sphenoid sinus. This study shows the significance of reviewing the entire CBCT scan for incidental findings.

• 대한핵의학회지
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• 제28권3호
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• pp.397-401
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• 1994

저자들은 간 스캔상 간 우엽 전반에 걸친 냉소를 보여 공간점유병소로 생각되었던 Budd-Chiari증후군 1예를 경험하였다. 본례는 복부팽만을 주소로 본원 내원하여 시행한 간 스캔상 간 우엽 전반에 걸친 집적감소를 보여 만성 간 질환에 동반된 간 종괴로 생각하였으나 복부 전산화 단층촬영과 자기공명촬영에서 간우엽의 경색이 의심되었다. 자기공명혈관촬영과 초음파 도플러를 시행하였으며 우측 간정맥과 중앙 간정맥폐쇄를 보여 Budd-Chiari증후군으로 진단된 경우이다. 하대정맥의 폐쇄소견은 보이지 않았다. 이를 문헌고찰과 함께 보고하는 바이다.

• 한국항공우주학회지
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• 제43권5호
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• pp.466-471
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• 2015

본 논문에서는 광역 관측을 위하여 새롭게 제안되고 있는 TOPS SAR 운용기법에 대한 모드 설계 및 성능 분석을 수행하였다. TOPS 모드는 기존 ScanSAR 모드의 단점인 scalloping을 개선하기 위하여 새롭게 제안된 모드로서, SAR 진행방향으로 안테나 빔을 조향하면서 영상 데이터를 획득하는 새로운 SAR 영상 획득 기술이다. 본 논문에서는 TOPS 모드에 대한 기술적 운용 개념을 소개하고, SAR 운용 변수를 추출하기 위한 모드 설계 결과를 제시한다. 또한 설계된 모드 변수를 이용하여 SAR 주요 성능인 IRF, NESZ, 및 DTAR을 분석하여 제시한다.

• 한국컴퓨터그래픽스학회논문지
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• 제29권3호
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• pp.59-67
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• 2023

본 논문은 몸체 3D 스캔과 모션 캡처 장비를 활용한 3D 애니메이션 형태의 바디 프로필을 제안한다. 사용자는 미리 정해진 몇 개의 포즈에 대하여 3D 스캔을 수행함으로써 애니메이션 형태를 가진 자신만의 바디 프로필을 제작할 수 있다. 이를 위하여 일련의 포즈를 수행하는 템플릿 애니메이션을 모션 캡처를 통하여 획득하였고, 사용자로부터 획득된 3D 스캔 데이터를 애니메이션의 각 정점 포즈에 포즈 공간 디포머(Pose-space deformer)를 통하여 매핑시켰다. 이를 통하여 만들어진 3D 애니메이션 형태의 바디 프로필은 기존의 정적인 2D 이미지나 3D 스캔데이터보다 사용자에게 더 큰 만족도를 줄 수 있음을 확인할 수 있다.