• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.7A
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• pp.676-682
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• 2002

In this paper, an effective stereo image compression and reconstruction technique using a new adaptively compensated-disparity prediction scheme is proposed. That is, by adaptively predicting the mutual correlation between the stereo image using the proposed method, the bandwidth of the stereo input image can be compressed to the level of the conventional 2D image and the predicted image also can be effectively reconstructed using this transmitted reference image and disparity data in the receiver. Especially, in the proposed method, once the feature values are extracted from the input stereo image, then the matching window size for the predicted image reconstruction is adaptively selected in accordance with the magnitude of this feature values. From this adaptive disparity estimation method, reduction of the mismatching probability of the disparity vectors is expected and as a result, the image quality in the reconstructed image can be improved. In addition, from some experiments using the CCETT's stereo images of 'Fichier', 'Manege' and 'Tunnel', it is shown that the proposed method improves the PSNR of the reconstructed image to about 9.08 dB on average by comparing with that of the conventional methods. And also, it is found that there is almost no difference between the original image and the predicted image reconstructed through the proposed method by comparison to that of the conventional methods.

• Journal of the Korean Society for Nondestructive Testing
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• v.36 no.1
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• pp.27-34
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• 2016

The type of ultrasound transducer used influences the quality of a reconstructed ultrasound image. This study analyzed the effect of transducer type on ultrasound computed tomography (UCT) image quality. The UCT was modeled in an ultrasound simulator by using a 5 cm anatomy model and a ring-shape 5 MHz 128 transducer array, which considered attenuation, refraction, and reflection. Speed-of-sound images were reconstructed by the Radon transform as the UCT image modality. Acoustic impedance images were also reconstructed by the delay-and-sum (DAS) method, which considered the speed of sound information. To determine the optimal combination of transducers in observation, point-source, flat, and focused transducers were tested in combination as trasmitters and receivers; UCT images were constructed from each combination. The combination of point-source/flat transducer as transmitting and receiving devices presented the best reconstructed image quality. In UCT implementation, the combination of a flat transducer for transmitting and a point transducer for receiving permitted acceptable image quality.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.5
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• pp.991-996
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• 2007

Recently, a computational reconstruction method using an integral imaging technique, which is a promise three-dimensional display technique, has been actively researched. This method is that 3-D images can be digitally reconstructed at the required output planes by superposition of all of the inversely enlarged elemental images by using a hypothetical pinhole array model. However, the conventional method mostly yields reconstructed images having a low-resolution, because there are some intensity irregularities with a grid structure at the reconstructed mage plane by using square-type elemental images. In this paper, to overcome this problem, we propose a novel computational integral imaging reconstruction (CIIR) method using round-type mapping model. Proposed CIIR method can overcome problems of non-uniformly reconstructed images caused from the conventional method and improve the resolution of 3-D images. To show the usefulness of the proposed method, both computational experiment and optical experiment are carried out and their results are presented.

• Journal of Sasang Constitutional Medicine
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• v.31 no.1
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• pp.79-93
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• 2019

Objective The purpose of this study was to show that the characteristics of the Sasang Constitutional Medical theory(SCM) are different from the traditional medical theory by comparing their theories of humans and pathophysiology. Methods The establishments and developments of the traditional medical theory were reviewed. Then the hypothesis that the theoretical foundation of SCM is different from that of the traditional medical theory was tested by comparing the traditional medical theory and SCM with respect to the theories of humans and the reconstructed theory of pathophysiology. Results The main findings of this study can be summarized as follows. 1. The theory of SCM reconstructed the traditional medical theory by shifting the paradigm concerning the structure of human existence. 2. The theory for SCM reconstructed the theory of pathophysiology by expanding Confucian moral theory from an experiential perspective. 3. The theory of SCM categorizes humans into four constitution groups according to congenital individuality in emotional expressions and pathophysiological functions. The categorization is based on medical treatment through which it was found that there are congenital individuality in the expression of his moral feelings. 4. The reconstructed pathophysiological theory of the SCM provides the foundation for establishing a verifiable medical theory. Discussion and conclusion The Sasang Constitutional Medical Theory is based on the idea that humans do not follow the changes of Nature but pursue morality and wealth in the Sasang system of the Heavenly qi and human affairs. Therefore, the theory is founded on Confucian moral theory but develops its own view of the theory of pathophysiology by way of experiential interpretation.

• Journal of KIISE:Computing Practices and Letters
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• v.14 no.1
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• pp.96-100
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• 2008

An ontology provides an explicit specification of concepts and relations on information extracted from database or on human knowledge. Using an ontology, The information can be reconstructed according to semantic relations. In this paper. IT-People Event Ontology is constructed using people information extracted from web portals. IT-People Event Ontology represents constant information and time-temporal information on people. A system using this ontology outputs the well-organized reconstructed information on a specific individual in interest, and then the reconstructed information is suitable for users' demand.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38C no.10
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• pp.911-919
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• 2013

Evaluation of the effect of radial distortion for a holographic stereogram demands conducting an experiment which comprises rendering of a 3D obejc, acquisition of perspective images, rearrangement of the acquired images for hogel images and quality assessment of the observing image reconstructed from the holographic stereogram. We propose numerical implementation of this evaluation by a specially developed algorithm for modeling of all required steps. The modeling is done by using a numerical model of an optical engine for generation of radially distorted hogel images at various degrees of distortion. The distorted images are used to form the holographic stereogram and to make the numerically reconstructed images from the holographic stereogram which are observed by an observer at desired location. The reconstructed images are compared by using PSNR.

• The Transactions of the Korean Institute of Power Electronics
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• v.21 no.4
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• pp.343-350
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• 2016

Generally, the average phase current is sampled at the midpoint of a PWM signal for the vector control of an AC motor. The three-phase current can also be reconstructed from a DC-link shunt resistor by sampling the shunt voltage during the active vectors of the SVPWM. However, the reconstructed current is different from the average current because of the deviation of the sampling point from the midpoint of the PWM signal. This paper proposes an algorithm to estimate the average current from the reconstructed current in a single-shunt inverter. The proposed method is derived from the phase current slopes based on switching states and corresponding switching time. In addition, the proposed method is generalized for all the six sectors of the space vector hexagon. The validity of the proposed algorithm is verified with simulations and experiments.

• Journal of information and communication convergence engineering
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• v.14 no.1
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• pp.57-63
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• 2016

In generally, the resolution of reconstructed three-dimensional images can be seriously degraded by undesired occlusions in the integral imaging system, because the undesired information of the occlusion overlap the three-dimensional images to be reconstructed. To solve the problem of the undesired occlusion, we present an exemplar-based image restoration method in integral imaging system. In the proposed method, a minimum spanning tree-based stereo matching method is used to remove the region of undesired occlusions in each elemental image. After that, the removed occlusion region of each elemental images are re-established by using the exemplar-based image restoration method. For further improve the performance of the image restoration, the structure tensor is used to solve the filling error cause by discontinuous structures. Finally, the resolution enhanced three-dimensional images are reconstructed by using the restored elemental images. The preliminary experiments are presented to demonstrate the feasibility of the proposed method.

• Korean Journal of Optics and Photonics
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• v.17 no.4
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• pp.329-334
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• 2006

We have reconstructed 3-dimensional images by using the digital holographic microscope and the Mask-cut phase unwrapping algorithm. Off-axis holograms recorded with a magnified image of the microscopic object lens and reference beam are numerically reconstructed in amplitude and phase image by the Fresnel diffraction approximation. We have simultaneously reconstructed 2-dimensional and 3-dimensional images of the sub-micrometer objects.

• Archives of Plastic Surgery
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• v.37 no.5
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• pp.702-704
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• 2010

Purpose: Chordoma is a rare primary osseous tumor arising from the remnants of the primitive notochord. It occurs once in 2,000,000. It is characterized by its slow growth, high frequency to invade destroy bone by direct extension. We experienced giant sacral chordoma and reconstructed with gluteal advancement flap. Methods: A 52-year-old woman presented with a 2-years history of gluteal pain. In the biopsy study revealed sacral chordoma. MRI study showed $13{\times}12{\times}10\;cm$ sized m0cs. We approached anterior and posterior resection and reconstructed with bilateral gluteus maximus advancement flap. Results: After the operation, blader and anal function were slightly decreased. But, 4 months later those were almost fully recovered. There was no significant complication and recurrence after 2-years follow-up. Conclusion: Chordoma is characterized by its slow growth, high frequency to invade and destroy bone by direct extension. Wide surgical resection is the only curative procedure. We report a ase of giant sacral chordoma which was successfully treated by anterior and posterior approach and reconstructed with bilateral gluteal advancement flap.