• International Journal of CAD/CAM
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• v.3 no.1_2
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• pp.61-66
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• 2003

This paper describes a novel experiment that measures skin movement with respect to the flexional motion of a hand. The study was based on MR images in conjunction with CAD techniques. The MR images of the hand were captured in 3 different postures with surface markers. The surface markers attached to the skin where employed to trace skin movement during the flexional motion of the hand. After reconstructing 3D isosurfaces from the segmented MR images, the global registration was applied to the 3D models based on the particular bone shape of different postures. Skin movement was interpreted by measuring the centers of the surface markers in the registered models.

• Korean Journal of Remote Sensing
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• v.23 no.5
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• pp.401-408
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• 2007

Animated anaglyph is the most cost-effective method for 3D stereo visualization of virtual or actual 3D geo-based data model. Unlike 3D anaglyph scene generation using paired epipolar images, the main data sets of this study is the multi-typed 3D feature model containing 3D shaped objects, DEM and satellite imagery. For this purpose, a prototype implementation for 3D animated anaglyph using OpenGL API is carried out, and virtual 3D feature modeling is performed to demonstrate the applicability of this anaglyph approach. Although 3D features are not real objects in this stage, these can be substituted with actual 3D feature model with full texture images along all facades. Currently, it is regarded as the special viewing effect within 3D GIS application domains, because just stereo 3D viewing is a part of lots of GIS functionalities or remote sensing image processing modules. Animated anaglyph process can be linked with real-time manipulation process of 3D feature model and its database attributes in real world problem. As well, this approach of feature-based 3D animated anaglyph scheme is a bridging technology to further image-based 3D animated anaglyph rendering system, portable mobile 3D stereo viewing system or auto-stereo viewing system without glasses for multi-viewers.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.26 no.11A
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• pp.1938-1945
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• 2001

In this paper, a new scheme for image conversion of the 2D input images into the stereoscopic 3D images by using differential shifting method is proposed. First, the relative depth information is estimated by disparity and occlusion information from the input stereo images and then, each of image objects are segmented by gray-level using the estimated information. Finally, through the differential shifting of the segmented objects according to the horizontal parallax, a stereoscopic 3D image having optimal stereopsis is reconstructed. From some experimental results, it is found that the horizontal disparity can be improved about 1.6dB in PSNR for the reconstructed stereo image using the proposed scheme through comparing to that of the given input image. In the experiment of using the commercial stereo viewer, the reconstructed stereoscopic 3D images, in which each of the segmented objects are horizontally shifted in the range of 4 ∼5 pixels are also found to have the mast improved stereopsis.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.32B no.9
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• pp.1171-1180
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• 1995

In this paper, we present a 3-D object recognition system in which the 3-D Hough transform domain is employed to represent the 3-D objects. In object modeling step, the features for recognition are extracted from the CAD models of objects to be recognized. Since the approach is based on the CAD models, the accuracy and flexibility are greatly improved. In matching stage, the sensed image is compared with the stored model, which is assumed to yield a distortion (location and orientation) in the 3-D Hough transform domain. The high dimensional (6-D) parameter space, which defines the distortion, is decomposed into the low dimensional space for an efficient recognition. At first we decompose the distortion parameter into the rotation parameter and the translation parameter, and the rotation parameter is further decomposed into the viewing direction and the rotational angle. Since we use the 3-D Hough transform domain of the input images directly, the sensitivity to the noise and the high computational complexity could be significantly alleviated. The results show that the proposed 3-D object recognition system provides a satisfactory performance on the real range images.

• Journal of Ocean Engineering and Technology
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• v.27 no.6
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• pp.100-105
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• 2013

This paper presents a sea surface reconstruction method that uses measured radar images by applying filtering techniques and identifying wave characteristics of the surrounding the Ieodo ocean research station using WaveFinder (X-band wave measurement radar), which is installed in the station. In addition, the results obtained from real radar images are used to verify the reconstructed sea surface. WaveFinder is a marine system that was developed to measure wave information in real time. The WaveFinder installed in the station could acquire sequent images for the sea surface at constant time intervals to obtain real time information (Wave height, mean wave period, wave directionality, etc.) for the wave by getting a three-dimensional spectrum by applying an FFT algorithm to the acquired sequent images and wave dispersion relation. In particular, we found the wave height using the SNR (Signal to noise ratio) of the acquired images. The wave information measured by WaveFinder could be verified by comparing and analyzing the results measured using the wave measurement instrument (Sea level monitor) in the station. Additionally, the wave field around the station could be reconstructed through the three-dimensional spectrum and the inverse FFT filtering from the analyzed results for the measured radar images. We verified the applicability of the sea surface reconstruction method by comparing the measured and simulated sea surfaces.

• Journal of Korea Multimedia Society
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• v.19 no.2
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• pp.163-169
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• 2016

In Korea, prostate cancer accounted for generating growth rate second the following thyroid cancer, because of western dietary habits. Survival rate of prostate cancer after clinical behavior is changed depend on follow-up management. A telemedicine have been applied to replacement of medical specialist in rural area, and a quick reaction to emergency situation. Our study developed prostate 3-dimensional (3D) visualization program and designed prostate aftercare system architecture, called smart care, using a device that can access the Internet. Region of interest (ROI) in prostate was manually segmented by physicians and visualized to 3D objects and sent to PACS Server as DICOM images. So, medical personnel could confirm patients' data along with 3D images not only PACS system, but also portable device like a smart phone. As a result, we conducted the aftercare service to 98 patients and visualize 3D prostate images. 3D images had advantage to instinctively apprehend where lesion is and make patients to understand state of their disease easily. In the future, should conduct an aftercare service to more patients, and will obtain numerical index through follow-up study to an accurate analysis.

• Proceedings of the IEEK Conference
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• 1998.10a
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• pp.927-930
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• 1998

This paper presents a new method for reconstructing 3 dimensional object model using a zoom camera. The proposed method uses zoom images to find the distance(D) between camera and object. Also the method uses images obtained around the object to find an $angle(\theta)$ between two connected planes of the object. With the D and $\theta,$ we can reconstruct the real sized 3-D model of object with less errors without stereo camera or rangefinder.

• Journal of Broadcast Engineering
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• v.18 no.6
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• pp.795-807
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• 2013

In recent years, 2D-to-3D conversion techniques have gained much attraction. Most of conventional methods focused on natural images such as movie, animation and so forth. However, it is difficult to apply these techniques to window images mixed with text, image, logo, and icon. Also, different depth values of text pixels will cause distortion and a proper 3D image can not be delivered in some situations. To solve this problem, we propose a method to classify a given image into either a window or a natural image. For the window image, only rectangular image regions (RIR) are detected and converted in 3D. Other text and background are displayed in 2D. The proposed method was performed on more than 10,000 test images. In the experimental results, the detection ratio of window image reaches 97% and RIR detection ratio is 87%.

• Journal of the korean academy of Pediatric Dentistry
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• v.47 no.1
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• pp.17-24
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• 2020

The purpose of this study was to evaluate the accuracy and precision of the three-dimensional (3D) imaging system of children's facial soft tissue by comparing linear measurements. The subjects of the study were 15 children between the ages of 7 and 12. Twenty-three landmarks were pointed on the face of each subject and 16 linear measurements were directly obtained 2 times using an electronic caliper. Two sets of 3D facial images were made by the 3D scanner. The same 16 measurements were obtained on each 3D image. In the accuracy test, the total average difference was 0.9 mm. The precision of 3D photogrammetry was almost equivalent to that of direct measurement. Thus, 3D photogrammetry by the 3D scanner in children had sufficient accuracy and precision to be used in clinical setting. However, the 3D imaging system requires the subject's compliance for exact images. If the clinicians provide specific instructions to children while obtaining 3D images, the 3D device is useful for investigating children's facial growth and development. Also the device can be a valuable tool for evaluating the results of orthodontic and orthopedic treatments.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.7 no.4
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• pp.567-574
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• 2006

This paper focuses on lossy medical image compression methods for medical images that operate on three-dimensional(3-D) irreversible integer wavelet transform. We offer an application of unbalanced tree structure algorithm to medical images, using a 3-D unbalanced wavelet decomposition and a 3-D unbalanced spatial dependence tree. The wavelet decomposition is accomplished with integer wavelet filters implemented with the lifting method. We have tested our encoder on volumetric medical images using different integer filters and 16 coding unit size. The coding unit sizes of 16 slices save considerable dynamic memory(RAM) and coding delay from full sequence coding units used in previous works. If we allow the formation of trees of different lengths, then we can accomodate more transaxial scales than three. Then the encoder and decoder can then keep track of the length of the tree in which each pixel resides through the sequence of decompositions. Results show that, even with these small coding units, our algorithm with I(5,3)filter performs as well and better in lossy coding than previous coding systems using 3-D integer unbalanced wavelet transforms on volumetric medical images.