• Journal of Institute of Control, Robotics and Systems
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• v.12 no.3
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• pp.248-254
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• 2006

It is necessary to improve the exactness and adaptation of the working environment for the intelligent robot system. The vision sensor have been studied for a long time at this points. However, it has many processes and difficulties for the real usages. This paper proposes a visual servoing in the virtual environment to support OLP(Off-Line-Programming) path compensation and supplement the problem of complexity of the old kinematical calibration. Initial robot path could be compensated by pixel differences between real and virtual image. This method removes the varies calibrations and 3D reconstruction process in real working space. To show the validity of the proposed approach, virtual space servoing with stereo camera is carried out with WTK and openGL library for a KUKA-6R manipulator and updated real robot path.

• Journal of Korea Society of Digital Industry and Information Management
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• v.12 no.1
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• pp.27-33
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• 2016

In this study we propose a method for 3D landform reconstruction and object modeling method by generating contour lines on the map using a depth sensor which abstracts characteristics of geological layers from the depth map. Unlike the common visual camera, the depth-sensor is not affected by the intensity of illumination, and therefore a more robust contour and object can be extracted. The algorithm suggested in this paper first abstracts the characteristics of each geological layer from the depth map image and rearranges it into the proper order, then creates contour lines using the Bezier curve. Using the created contour lines, 3D images are reconstructed through rendering by mapping RGB images of the visual camera. Experimental results show that the proposed method using depth sensor can reconstruct contour map and 3D modeling in real-time. The generation of the contours with depth data is more efficient and economical in terms of the quality and accuracy.

• Journal of the Semiconductor & Display Technology
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• v.19 no.4
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• pp.71-76
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• 2020

In this paper, we propose a super-resolution method that reconstructs compressed low-resolution images into high-resolution images. We propose a CNN model with a small number of parameters, and even if quantization is applied to the proposed model, super-resolution can be implemented without deteriorating the image quality. To further improve the quality of the compressed low-resolution image, a new degradation model was proposed instead of the existing bicubic degradation model. The proposed degradation model is used only in the training process and can be applied by changing only the parameter values to the original CNN model. In the super-resolution image applying the proposed degradation model, visual artifacts caused by image compression were effectively removed. As a result, our proposed method generates higher PSNR values at compressed images and shows better visual quality, compared to conventional CNN-based SR methods.

• Proceedings of the IEEK Conference
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• 2001.06d
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• pp.227-230
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• 2001

In this paper, We present a 3D image data for ocular refina. This 3D display techniques are used voxel(cuboid) projection. Voxel is 3D reconstruction method of the pixel. In this paper, 3D image display system is constructed under PC environment and programed based on modular programming by using Visual C++. The hole procedures are composed of data preparation, 3D Display over transformation and scaling.

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.41.2-41
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• 2002

The stereo correspondence of two retinal images is one of the most difficult problems in stereo vision because the reconstruction of 3-D scene is a typical visual ill-posed problem. So far there still have been many unsolved problems, one of which is to reconstruct 3-D scene for a monochromatic surface because there is no clue to make a correspondence between two retinal images. We consider this problem with two layered self-organization neural network to simulate the competitive and cooperative interaction of binocular neurons. A...

• Journal of the Korean Arthroscopy Society
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• v.12 no.2
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• pp.118-124
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• 2008

Purpose: Recent development and advances in the arthroscopic surgical techniques for anterior cruciate ligament(ACL) reconstruction have led to the ideal location for more oblique anatomic point of the femur from 10 to 10:30 o'clock(in the right knee) and from 2 to 1:30 o'clock(in the left knee) in the frontal plane. This study was performed to compare the operative methods and the radiologic results of the femoral tunnels made through the tibial tunnel(trans-tibial approach) and the anteromedial portal. Materials and Methods: From January 2003 to May 2004, on hundred reconstructions of ACL were performed. Group I(the femoral tunnel made through the tibial tunnel) consisted of 50 cases and group I(the femoral tunnel made through the anteromedial portal) consisted of 50 cases. The operative methods and the radiographic results of the femoral tunnels were compared. Results: Femoral tunnel was made more easily at more oblique anatomic point in group II than in group I. In group II, better visual field was achieved at the angle of 100? flexion of the knee joint, the risks of the posterior cortical breakage and the tunnel-graft mismatching were reduced more, and the divergence of femoral interference screw from the radiograph decreased more than in group I(p<0.05). The angle between the femoral tunnel and the longitudinal axis of ACL increased in group II. Conclusion: Anteromedial portal technique was useful for femoral tunneling toward 10 to 10:30 o'clock(in the right knee) and 2 to 1:30 o'clock(in the left knee) in ACL reconstruction. Level of Evidence:Level III, case-control study.

• Archives of Craniofacial Surgery
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• v.15 no.2
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• pp.70-74
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• 2014

Background: Many options are available to cover a palatal defect, including local or free flaps. The objective of this study was to evaluate the usefulness of palatal mucoperiosteal island flap in covering a palatal defect after tumor excision. Methods: Between October 2006 and July 2013, we identified 19 patients who underwent palatal reconstruction using a palatal mucoperiosteal island flap after tumor excision. All cases were retrospectively analyzed by defect location, size, tumor pathology, type of reconstruction, and functional outcomes. Speech and swallowing functions were evaluated using a 7-point visual analog scale (VAS) score. Results: Among the 19 patients, there were 7 men and 12 women with an age range of 25 to 74 years (mean, $52.5{\pm}14.3$ years). The size of flaps was $2-16cm^2$ (mean, $9.4{\pm}4.2cm^2$). Either unilateral or bilateral palatal island flaps were used depending on the size of defect. During the follow-up period (mean, $32.7{\pm}21.4$ months), four patients developed a temporary oronasal fistula, which healed without subsequent operative. The donor sites were well re-epithelized. Speech and swallowing function scores were $6.63{\pm}0.5$ and $6.58{\pm}0.69$ on the 7-point VAS, indicating the ability to eat solid foods and communicate verbally without significant disability. Conclusion: The palatal mucoperiosteal island flap is a good reconstruction modality for palatal defects if used under appropriate indications. The complication rates and donor site morbidity are low, with good functional outcomes.

• Archives of Craniofacial Surgery
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• v.25 no.4
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• pp.161-170
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• 2024

Background: The eyes are the central aesthetic unit of the face. Maxillofacial trauma can alter facial proportions and affect visual function with varying degrees of severity. Conventional approaches to reconstruction have numerous limitations, making the process challenging. The primary objective of this study was to evaluate the application of three-dimensional (3D) navigation in complex unilateral orbital reconstruction. Methods: A prospective cohort study was conducted over 19 months (January 2020 to July 2021), with consecutive enrollment of 12 patients who met the inclusion criteria. Each patient was followed for a minimum period of 6 months. The principal investigator carried out a comparative analysis of several factors, including fracture morphology, orbital volume, globe projection, diplopia, facial morphic changes, lid retraction, and infraorbital nerve hypoesthesia. Results: Nine patients had impure orbital fractures, while the remainder had pure fractures. The median orbital volume on the normal side (30.12 cm³; interquartile range [IQR], 28.45-30.64) was comparable to that of the reconstructed orbit (29.67 cm³; IQR, 27.92-31.52). Diplopia improved significantly (T(10)= 2.667, p= 0.02), although there was no statistically significant improvement in globe projection. Gross symmetry of facial landmarks was achieved, with comparable facial width-to-height ratio and palpebral fissure lengths. Two patients reported infraorbital hypoesthesia at presentation, which persisted at the 6-month follow-up. Additionally, five patients developed lower lid retraction (1-2 mm), and one experienced implant impingement at the infraorbital border. Conclusion: Our study provides level II evidence supporting the use of 3D navigation to improve surgical outcomes in complex orbital reconstruction.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.1099-1102
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• 2005

In this paper, a new visual servo method, which uses 5 axis picomotor to compensate the misalignment generated between a SLM and a CCD in a holographic storage device, was proposed and the effectiveness of it was proved by the experiment. In a holographic storage device, the data processing is done by the SLM and the CCD, and the shape of data is 2 dimensional binary patterns. Therefore, the exact image matching between the SLM and the CCD is very important, and the mismatching of it causes the errors in the data reconstruction. First, the brief introduction of a holographic data storage is given, then, BER concept which is errors caused by pixel mismatch between the SLM and the CCD is defined. Second, the geometric relation between 5 axis picomotor and the CCD movement is studied. Finally, the visual servo method using 5 axis picomotor to reduce the BER in a holographic storage device is proposed and experimented. From the experiment, we find that about 3% BER improvement is obtained by the proposed method.

• Hwankyungkyoyuk
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• v.16 no.2
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• pp.65-73
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• 2003

This study has an aim to construct a reference frame to analyze the appropriateness of environmental education(EE) materials of elementary schools, and to search the basic direction of the scheme for analysis. In addition, this study has an aim to induce what the results of this analysis suggests for the development and reconstruction of EE materials. It was analyzed how truly EE materials reflected contents selected as an analysis scheme, after grasping practical use and features of textbooks, audio-visual materials, and a web-site that are typical materials in EE of elementary schools. The results in textbook analysis were that there were a human-centered environmentalism in the EE unit ("Environmentally Sound National Development", 5th Grade) of Social Studies. The result in analysis of audio-visual materials "Environmental Warrior, Zentaforce" of EBS, were that there are unhealthy environmentalism in that material. In other words, technology itself is considered as a almighty means to solve environmental problems. Finally, the result in web-site analysis were that the "Environmental Class" of Ministry of Environment did not have sound environmentalism. The above result of study shows us that the most important thing in developing and using the environmental education materials is to have sound environmental values and EE perspective, to evaluate EE material with various point of view, to judge its result, and to use it.