• 전자공학회논문지S
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• 제35S권5호
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• pp.75-82
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• 1998

Conventional vector quantization (VQ) codebook design methods have several drawbacks such as edge degradation and high computational complexity. In this paper, we first made activity coordinates from the horizonatal and the vertical activity of the input block. Then it is mapped on the 2-dimensional interconnected codebook, and the codebook is designed using kohonen self-organizing map (KSFM) learning algorithm after the search of a codevector that has the minumum distance from the input vector in a small window, centered by the mapped point. As the serch area is restricted within the window, the computational amount is reduced compared with usual VQ. From the resutls of computer simulation, proposed method shows a better perfomance, in the view point of edge reconstruction and PSNR, than previous codebook training methods. And we also obtained a higher PSNR than that of classified vector quantization (CVQ).

• 한국수학교육학회:학술대회논문집
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• 한국수학교육학회 2007년도 제38회 전국수학교육연구대회 프로시딩
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• pp.37-50
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• 2007

평면도형의 탐구에서 기본이 되는 것은 무엇이며, 그것으로부터 평면도형의 내용들을 일관성 있게 구성할 수는 없는가? 이 글에서는 평면도형 탐구의 기본 요소가 삼각형이라는 관점을 제시하고, 삼각형을 중심으로 한 평면도형 탐구 활동 설계 및 교과서 내용 재구성의 몇 가지 예를 제시한다. 그리고 이러한 관점 및 설계가 지니는 수학교육적 의의에 대하여 논의한다.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송∙미디어공학회 2019년도 하계학술대회
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• pp.62-63
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• 2019

본 논문에서 개발하고자하는 다시점 스테레오 영상 기반의 3차원 깊이 정보 획득 기술은 스테레오 비전, light field, 가상시점, 방송 콘텐츠, 등 다양한 분야의 기술이 융합된 기술로 연구의 중요성이 매우 높다. 본 논문에서는 SGM 기반의 멀티베이스 라인 스테레오 정합 기술을 개발하고 다시점 스테레오 영상에 적용하여 깊이 정보를 획득하였다. 두 시점 간의 스테레오 정합에 있어서 다방향의 에너지 최소화 기술을 적용하고 시점 간의 정합비용함수를 누적하여 마지막으로 S공간 누적방법으로 최적의 깊이영상을 획득하였다. 기존의 스테레오 정합에 비하여 멀티베이스라인 스테레오 정합의 성능 향상을 확인하고 Middlebury 스테레오 영상을 이용하여 성능을 분석하였다.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2013년도 춘계학술발표대회
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• pp.301-302
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• 2013

본 논문에서는 집적 영상(Integral imaging)에서 3차원 영상을 자유시점에서 재생하는 방법에 대해 설명한다. 집적 영상은 완전시차와 연속적인 시점을 제공하기 때문에 자유시점 재생을 사용하여 3차원 물체의 측면을 재생할 수 있다. 따라서, 이러한 3차원 데이터를 사용하여 보다 향상된 3차원 영상의 시각화 및 패턴 인식이 가능할 수 있다. 이를 증명하기 위해 컴퓨터 시뮬레이션을 수행하였다.

• Nuclear Engineering and Technology
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• 제54권5호
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• pp.1747-1753
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• 2022

Compton imaging is the main method for locating radioactive hot spots emitting high-energy gamma-ray photons. In particular, this imaging method is crucial when the photon energy is too high for coded-mask aperture imaging methods to be effective or when a large field of view is required. Reconstruction of the photon source requires advanced Compton event processing algorithms to determine the exact position of the source. In this study, we introduce a novel method based on a Deep Learning algorithm with a Convolutional Neural Network (CNN) to perform Compton imaging. This algorithm is trained on simulated data and tested on real data acquired with Caliste, a single planar CdTe pixelated detector. We show that performance in terms of source location accuracy is equivalent to state-of-the-art algorithms, while computation time is significantly reduced and sensitivity is improved by a factor of ~5 in the Caliste configuration.

• 한국산업융합학회 논문집
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• 제27권2_2호
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• pp.319-324
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• 2024

In this paper, the Artificial Intelligence Space(AI-Space) for human-robot interface is presented, which can enable human-computer interfacing, networked camera conferencing, industrial monitoring, service and training applications. We present a method for representing, tracking, and objects(human, robot, chair) following by fusing distributed multiple vision systems in AI-Space. The article presents the integration of color distributions into particle filtering. Particle filters provide a robust tracking framework under ambiguous conditions. We propose to track the moving objects(human, robot, chair) by generating hypotheses not in the image plane but on the top-view reconstruction of the scene.

• Archives of Reconstructive Microsurgery
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• 제4권1호
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• pp.9-15
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• 1995

Free vascularized composite tissue transfer is more frequently underwent for reconstruction of complicated tissue defects with the recent advance of microsurgery. But postoperative result was not satifactory because of donor site morbidity, flap bulkiness and cosmetic problem. So would no longer be a problem if we can obtain the exact donor tissue required for the recipient site as allotransplantation and designing the flap. Allotransplantation has been resolved with the recent development of immunosuppressive agents, while reconstruction has made great progress with the refinement of microsurgical techniques in the last 20 years. The final sucess or failure of the operative procedure in transplantation is so utterly dependent no the availability of strategies that can control the immune system effectively, selectively, safely to allow allotransplantation of a nonvital body part. 1 used 2 strains of rats, BUF and LEW, for the limb allotransplantation as a composite tissue transfer. The primary goal of this program is to improve results in clinical transplantation by accelerating the transformation of new immunological knowledge into useful medicine. Two of the most promising new immunosuppressive compounds are FK-t06(FK) and rapamycin(RPM). Both drugs are antibiotic macrolide fungal fermentation products that presumably suppress the immune system in ways similar to cyclosporin(CyA). This study shows that two new immunosuppressive drugs compare the immunosuppressive activity and effectiveness of FK-506 and RPM for prevention of the limb allograft rejection in the rat. Additional experiments investigate the dose, route of administration and histologic findings. These data demonstrates that rapamycin is far more potent and effective than FK-506 when both compounds are administered by the intraperitoneal route, as well as prolonged graft survival significantly in a dose-route dependent manner. These results lead to the view that vascularized allograft composite tissue transfer can become a reality with the expectation of possible future application in reconstructive surgery of humans.

• 대한두개안면성형외과학회지
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• 제13권2호
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• pp.99-103
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• 2012

Purpose: Many surgical methods for reconstruction of orbital floor fracture have been reported, which include subciliary approach, transconjunctival approach, transantral and transnasal endoscopic approach, etc. The purpose of this study is to demonstrate a surgical technique and analyze the results of transnasal endoscopic approach with Foley catheter ballooning without implantation of artificial surgical material through subciliary approach. Methods: Between February 2007 and November 2010, 29 orbital floor fracture patients, who had no herniated muscles through bone fragments, were treated through transnasal endoscopic approach with Foley catheter ballooning. Under the endoscopic view, the operator identified the opening of maxillary sinus. After widening of the opening using forceps, the operator reduced the fragmented bone with curved suction tip. Thereafter, 18-Fr Foley catheter was inserted. Four weeks after the operation, the catheter was removed. Results: Preoperatively, 6 patients had diplopias, 4 patients had limitations of extraocular motions and 3 patients had enophthalmos. After removal of the Foley catheter 4 weeks after the operation, 2 patients had diplopias, 1 patient had a limitation of extraocular motion, 1 patient has an enophthalmos and 1 patient had numbness on the cheek. These symptoms were resolved about 6 months after the surgery. Conclusion: The operative technique of Foley catheter ballooning through transnasal endoscopic approach without implantation of the artificial surgical material through subciliary approach can be considered one of the appropriate techniques for orbital floor fracture.

• 대한두개안면성형외과학회지
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• 제18권2호
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• pp.76-81
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• 2017

Background: A transcaruncular approach is typically used for reconstructions of medial wall fractures. However, others reported that a transconjunctival approach was conducive for securing an adequate surgical field of view. In this study, we aimed to examine the extent of repair of medial wall fracture via a transconjunctival approach. Methods: We retrospectively reviewed the medical records of 50 patients diagnosed as having medial wall fracture via preoperative computed tomography and who underwent surgery between March 2011 and February 2014. The fracture location was defined by dividing each of the anterior-posterior and superior-inferior distances into three compartments. Results: A transcaruncular approach was used in 7 patients, while the transconjunctival approach was performed in the remaining 43 patients. The transconjunctival approach enabled a relatively broad range of repair that partially included the front and back of the medial wall, and was successful in 86% of the entire study population. Conclusion: It is known that more than 50% of total cases of the medial wall fracture occur mainly in the middle-middle portion, a majority of which can be reconstructed via a transconjunctival approach. We used a transconjunctival approach in identifying the location of the fracture on image scans except for cases including the fracture of the superior portion in patients with medial wall fracture. If it is possible to identify the location of the fracture, a transconjunctival approach would be an useful method for the reconstruction in that it causes no damages to the lacrimal system and is useful in confirming the overall status of the floor.

• 정보처리학회논문지B
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• 제12B권5호
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• pp.567-576
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• 2005

다중영상으로부터 투사 선분을 이용하여 3D 모델을 생성하고 각 면의 텍스쳐를 획득하는 구조 복원 기법을 제안한다 사용자는 매우 단순한 절차를 통해 정확한 3D 모델 데이터를 획득할 수 있다. 모델 파라메터 추정을 위해 내재된 비선형 최적화 방법은 사용자 지정 영상 선분과 모델의 투사 선분의 거리를 최소화하는 방법에 기반하고 있다. 모델링 기법의 기능적 주요 목표는 형상이 포함된 다중 영상으로부터 그 형상의 3차원 구조를 복원하고 각 면의 텍스쳐를 생성하는 것이다. 본 연구에서는 3D 정형체를 사용하여 사용의 편리성을 증대시킬 수 있고 정형체의 파라메터의 오차를 최소화하여 복원된 구조의 정확성을 높이는 방법을 제시한다. 제안된 방법은 유한 선분에 기반한 오차 함수를 도입하여 무한 직선에 기반한 방법보다 정확한 모델링이 가능하다. 제안된 방법을 다양한 실제 영상에 적용한 실험 결과를 제시하고 다중 영상기반 모델링 도구의 개발 과정에서의 기술적인 문제점과 해결책을 기술한다.