• Journal of the Korean Institute of Telematics and Electronics
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• v.24 no.6
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• pp.1005-1012
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• 1987

An adaptive scalar DCT-Wiener filtering method that can be applied to the problem of restoring an image degraded by white Gaussian noise is presented. In this method, the power spectrum needed to Winer filering is adaptively estimated in block-wise according to the lical properties in transform domain. In addition, overlapping method for reducing the block artifact is considered. Experimental results show that the adaptive Wiener filter by the proposed method yields performance improvement and better image quality over the nonadaptive one and the spatial Lee filter.

• Archives of Pharmacal Research
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• v.14 no.1
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• pp.87-92
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• 1991

In order to evaluate the pharmacological activities of Chinese medicine, nine Umbelliferae plants were selected and their restoring activity against dexamethasone-induced disorders, liver protective activity, antimicrobial activity, anti-inflammatory activity and antimutagenic activity were tested and compared. Angelica dahurica. Angelica acutiloba and Ostericum koreanum showed various activities in these tests at the dose used in this study.

• Journal of applied mathematics & informatics
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• v.18 no.1_2
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• pp.235-246
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• 2005

We present an interpolating, univariate subdivision scheme which preserves the discrete curvature and tangent direction at each step of subdivision. Since the polygon have a geometric information of some original(in some sense) curve as a discrete curvature, we can expect that the limit curve has the same curvature at each vertex as the control polygon. We estimate the curvature bound of odd vertices and give an error estimate for restoring a curve from sampled vertices on curves.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.7
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• pp.1290-1294
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• 2008

We present a novel deblurring algorithm for bi-level images blurred by some parameterizable point spread function. The proposed method iteratively searches unknown parameters in the point spread function and noise-to-signal ratio by minimizing an objective function that is based on the binariness and the difference between two intensity values of restoring image. In simulations and experiments, the proposed method showed improved performance compared with the Wiener filtering based method in terms of bit error rate after segmentation.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2012.11a
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• pp.5-8
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• 2012

Haze is an extreme reason of the reduction of contrast when capturing image in the outdoor. Recently, there are several single image dehazing techniques, but they are not robust in dynamic variations of natural environment caused by the thickness, coverage of haze and appearance of sunlight. In this paper, we propose an effective and robust method to restore degradation of hazy image. Compare with conventional methods, our proposal have better performance and computation time.

• Journal of Ship and Ocean Technology
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• v.2 no.1
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• pp.1-12
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• 1998

A method to predict the dynamic roll stability of hard-chine planing craft is presented. Starting with the equation of motion, an equation governing small roll perturbations is developed. The roll restoring moment acting on the hull is evaluated by considering “static”and dynamic contributions. The contribution of rudders and skegs, which is significant for this type of craft, is also determined. A worked example is presented to show how the method can be used to find the maximum center of gravity height for transverse stability.

• Proceedings of the KIEE Conference
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• 1994.11a
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• pp.117-119
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• 1994

While the projectile in the induction type coil guns is in motion, there exists an induced current in the sleeve coils of the projectile. The motion includes not only the z-axial movement but transversal movement. The projectile in coil guns, which is not supported physically, gets a force in the transversal axis to have a motion in this axis. As a result of this motion, sleeve effects are exhibited to the projectile. This paper presents the analysis of the secondary effect especially due to the propelling velocity of the projectile.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.197.1-197.1
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• 2003

Neuronal hyperexcitability followed by high level of intracellular calcium and oxidative stress play critical roles in neuronal cell death in stroke and neurotrauma. Hence, KR-31378, a novel benzopyran derivative was designed as a new therapeutic strategy for neuroprotection possessing both anti-oxidant and potassium channel modulating activities. In the present study, we tested for its neuroprotective efficacy against oxidative stress-induced cell death in primary cortical cultures and further investigated its neuroprotective mechanism. (omitted)

• Journal of Korean Dental Science
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• v.15 no.2
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• pp.152-161
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• 2022

Mandibular implant overdenture is a good treatment option for complete edentulous patients with restoring removable prosthesis. Mandibular implant overdenture with two implants and locator attachments is widely used. It is tissue-supported overdenture that is made with the concept of conventional complete denture fabrication. There are two patients who provided impressions by open mouth technique and closed mouth technique in each case. In both cases, mandibular implant overdentures were restored with functionally and aesthetically satisfying results.

• Journal of Yeungnam Medical Science
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• v.41 no.1
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• pp.4-12
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• 2024

Biomaterials have been used to supplement and restore function and structure by replacing or restoring parts of damaged tissues and organs. In ancient times, the medical use of biomaterials was limited owing to infection during surgery and poor surgical techniques. However, in modern times, the medical applications of biomaterials are diversifying owing to great developments in material science and medical technology. In this paper, we introduce biomaterials, focusing on calcium phosphate ceramics, including octacalcium phosphate, which has recently attracted attention as a bone graft material.