• Journal of IKEEE
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• v.14 no.4
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• pp.317-323
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• 2010

The video surveillance system is adopted in many places due to its efficiency and constancy in monitoring a specific area over a long period of time. However, many surveillance systems composed of a single static camera often produce unsatisfactory results due to their lack of field of view. In this paper, we present a video surveillance system based on wide baseline stereo cameras to overcome the limitation. We adopt the codebook algorithm and mathematical morphology to robustly model the foreground pixels of the moving object in the scene and calculate the trajectory of the moving object via 3D reconstruction. The experimental results show that the proposed system detects a moving object and generates a top view trajectory successfully to track the location of the object in the world coordinates.

• Archives of Plastic Surgery
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• v.35 no.2
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• pp.152-158
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• 2008

Purpose: Mandibulotomy approach and mandible sparing approach are most common methods for oropharyngeal cancer surgery. Good surgical view and convenience of flap inset are advantages of mandibulotomy approach but deformity of mandible contour, postoperative malocclusion and radionecrosis are its limitations. To make up for the limitations, mandible sparing method is commonly performed, but limited surgical view and difficulties of flap inset are the weak points of this approach. The purpose of the study is to compare mandibulotomy and mandible sparing approaches in postoperative complications and progression of the treatment in oropharyngeal cancer operation and reconstruction. Methods: Single reconstructive microsurgeon operated for oropharyngeal cancer patients with different surgeons of head and neck department who prefer mandibulotomy and mandible sparing approach respectively, and we compared the frequency of postoperative complication, operation time, duration of hospitalization and recurrence rate between two different surgical approaches. Results: Mandibulotomy approach was used in 18 patients and mandible sparing approach was used in 15 patients. In mandibulotomy approach, there happened one case of teeth injury and one case of necrosis of skin and gingiva, but there happened no malocclusion and radionecrosis. In mandible sparing approach, there were 3 cases of fistula and 2 cases of infection which are significantly higher than mandibulotomy approach. There were no significant differences between early regional recurrence and duration of hospitalization. Conclusion: In this study we compared two different methods for the surgical approach in oropharyngeal cancer surgery. As mandible sparing approach has difficulties of limited surgical view, it can be used for the limited indications of anterior tongue and mouth floor cancer. Mandibulotomy approach has advantages of good surgical view and convenience of flap inset. In this method preservation of gingival tissue, watertight fashion suture, delicate osteotomy and plate fixation to maintain occlusion are the key points for the successful results.

• Journal of Institute of Control, Robotics and Systems
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• v.6 no.5
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• pp.383-389
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• 2000

This paper presents a stereo camera system that provides a Pair of stereo images using a Biprism. The equivalent of a stereo Pair of images is formed as the left and right halves of a single CCD image. The system is therefore cheap and extremely easy to calibrate since it requires only one CCD camera. An additional advantage of the geometrical set-up is that corresponding features lie on the same scanline automatically, The single camera and Biprism have led to a simple stereo system for which correspondence is very easy and which is accurate for nearby objects in a small field of view. Since we use only a single lens, calibration of the system is greatly simplified. Given the parameters in the Biprism-stereo camera system, we can reconstruct the 3-D structure using only the disparity between the corresponding points.

• Archives of Reconstructive Microsurgery
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• v.11 no.1
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• pp.19-28
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• 2002

From 1994-2001, 25 mutilated digits were reconstructed with immediate toe-to-hand transfer in acute hand injury in 21 patients. There were 15 cases of great toe-to-hand transfer(partial great toe transfer 8 cases, modified wrap-around procedure 2 cases, and trimmed great toe transfer 2 cases) for thumb reconstruction, 2 cases of second toe transfer for index reconstruction, and 4 cases of simultaneous two toe-to-hand transfer(great toe & second toe transfer 1 case, bilateral second-toe transfer 2 cases, combined second & third toe transfer 1 case) for reconstruction of multiple digit amputations. Two cases of emergency exploration(2/25, 8%) were successfully salvaged. The incidence of emergency exploration and postoperative infection was not significantly different from that of the elective toe-to-hand transfer cases. Duration of industrial insurance coverage was 225 days, which is much shorter than that of elective cases. Among 43% of patients maintained their original job even after injury and immediate toe-to-hand transfer. The subjective satisfaction self- assessment scores of aesthetic appearance and function on the new reconstructed thumb were 80 and 88 in average, respectively, over a total score of 100. These were higher than those of reconstruction of other digits, but lower than those of elective reconstruction. The donor site after harvest of the great toe was mostly unsatisfied in a view of appearance. Immediate toe-to-hand transfer provides many advantages over elective procedure in acute hand injuries such as single stage reconstruction, shortened convalescent period, early return to work and efficient socio-economic factor. Furthermore because there were no significant differences in success rate, frequency of complications or ultimate functional result, immediate toe-to-hand transfer is a safe and reliable procedure in case of limited indications for acute digits loss.

• Investigative Magnetic Resonance Imaging
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• v.19 no.1
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• pp.19-30
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• 2015

Purpose: A new compressed sensing technique by iterative truncation of small transformed coefficients (ITSC) is proposed for fast cardiac CINE MRI. Materials and Methods: The proposed reconstruction is composed of two processes: truncation of the small transformed coefficients in the r-f domain, and restoration of the measured data in the k-t domain. The two processes are sequentially applied iteratively until the reconstructed images converge, with the assumption that the cardiac CINE images are inherently sparse in the r-f domain. A novel sampling strategy to reduce the normalized mean square error of the reconstructed images is proposed. Results: The technique shows the least normalized mean square error among the four methods under comparison (zero filling, view sharing, k-t FOCUSS, and ITSC). Application of ITSC for multi-slice cardiac CINE imaging was tested with the number of slices of 2 to 8 in a single breath-hold, to demonstrate the clinical usefulness of the technique. Conclusion: Reconstructed images with the compression factors of 3-4 appear very close to the images without compression. Furthermore the proposed algorithm is computationally efficient and is stable without using matrix inversion during the reconstruction.

• Proceedings of the KSRS Conference
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• 2008.10a
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• pp.137-140
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• 2008

Recently many areas require wide field of view images. Such as surveillance, virtual reality, navigation and 3D scene reconstruction. Conventional camera systems have a limited filed of view and provide partial information about the scene. however, omni directional vision system can overcome these disadvantages. Acquiring 360 degree panorama images requires expensive omni camera lens. In this study, 360 degree panorama image was tested using a low cost optical reflector which captures 360 degree panoramic views with single shot. This 360 degree panorama image system can be used with detailed positional information from GPS/INS. Through this study result, we show 360 degree panorama image is very effective tool for mobile monitoring system.

• Journal of Gastric Cancer
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• v.15 no.2
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• pp.132-138
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• 2015

Single-incision laparoscopic total gastrectomy for gastric cancer has recently been reported by Seoul National University Bundang Hospital. However, this is not a popular procedure primarily because of the technical difficulties involved in achieving consistent intracorporeal esophagojejunostomy. At Seoul National University Bundang Hospital, we recently introduced a simple, easy-to-use, low-profile laparoscopic manual scope holder that enables the maintenance of a stable field of view, the most demanding condition in single-port gastrectomy. In this technical report, we describe in detail the world's first solo single-incision laparoscopic total gastrectomy with D1+ lymph node dissection and intracorporeal esophagojejunostomy for proximal early gastric cancer.

• Nuclear Engineering and Technology
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• v.54 no.5
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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.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.11
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• pp.2563-2568
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• 2010

SAII (synthetic aperture integral imaging) is a useful technique to record many multi view images of 3D objects by using a moving camera and to reconstruct 3D depth images from the recorded multiviews. This is largely composed of two processes. A pickup process provides elemental images of 3D objects and a reconstruction process generates 3D depth images computationally. In this paper, a signal model for SAII is presented. We defined the granular noise and analyzed its characteristics. Our signal model revealed that we could reduce the noise in the reconstructed images and increase the computational speed by reducing the shifting distance of a single camera.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.43 no.3 s.309
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• pp.8-15
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• 2006

Obstacle detection is an important task for many mobile robot applications. The methods using stereo vision and optical flow are computationally expensive. Therefore, this paper presents a vision-based obstacle detection method using only two view images. The method uses a single passive camera and odometry, performs in real-time. The proposed method is an obstacle detection method using 3D reconstruction from taro views. Processing begins with feature extraction for each input image using Dr. Lowe's SIFT(Scale Invariant Feature Transform) and establish the correspondence of features across input images. Using extrinsic camera rotation and translation matrix which is provided by odometry, we could calculate the 3D position of these corresponding points by triangulation. The results of triangulation are partial 3D reconstruction for obstacles. The proposed method has been tested successfully on an indoor mobile robot and is able to detect obstacles at 75msec.