• The Journal of the Korea institute of electronic communication sciences
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• v.16 no.6
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• pp.1303-1310
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• 2021

We propose an edge-preserving transmission estimation by comparing the patch-based dark channel and the pixel-based dark channel near the edge, in order to improve the quality of outdoor images deteriorated by conditions such as fog and smog. Moreover, we propose a refinement that applies the Guided Image Filtering (GIF), a kind of edge-preserving smoothing filtering methods, to edges using Laplacian operation for natural restoration of image objects and backgrounds, so that we can dehaze a single image and improve the visibility effectively. Experimental results carried out on various outdoor hazy images that show the proposed method has less computational complexity than the conventional methods, while reducing distortion such as halo effect, and showing excellent dehazing performance. In It can be confirmed that the proposed method can be applied to various fields including devices requiring real-time performance.

• Journal of Digital Policy
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• v.2 no.3
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• pp.1-7
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• 2023

In this paper, I proposes a method for performing single image super resolution by separating texture-spatial domains and then classifying features based on detailed information. In CNN (Convolutional Neural Network) based super resolution, the complex procedures and generation of redundant feature information in feature estimation process for enhancing details can lead to quality degradation in super resolution. The proposed method reduced procedural complexity and minimizes generation of redundant feature information by splitting input image into two channels: texture and spatial. In texture channel, a feature refinement process with step-wise skip connections is applied for detail restoration, while in spatial channel, a method is introduced to preserve the structural features of the image. Experimental results using proposed method demonstrate improved performance in terms of PSNR and SSIM evaluations compared to existing super resolution methods, confirmed the enhancement in quality.

• The Journal of Korean Academy of Prosthodontics
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• v.61 no.2
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• pp.135-142
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• 2023

Resin-bonded fixed partial denture (RBFPD)as known as Maryland bridge is is a well-known conservative method for its minimized invasion of the teeth for an anterior single tooth edentulous area. Despite of its various advantages, RBFPD was not widespread because of its high debonding rates, non-esthetic look or weak structure for material property. Currently, with the introduction of zirconia to dental material for RBFPD, Maryland bridge entered upon a new phase. Zirconia surmounts poor esthetics of metal framework, having proper strength, and overcomes ceramic's structural weakness, being sufficiently esthetic. In this case, edentulous area of maxillary left lateral incisor was restored using zirconia resin-bonded fixed partial denture. Restoration of missing tooth in anterior area was achieved using non-invasive and esthetic prosthesis, then we report this case as satisfactory results were obtained for both the operator and the patient.

• Restorative Dentistry and Endodontics
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• v.37 no.2
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• pp.84-89
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• 2012

Objectives: This study analyzed the difference in color caused by different thickness in enamel layer of composite resins when applied with single and layering placement technique, and evaluated if the results agreed with the shade guide from the manufacturers to verify reliability of the color matching process of the manufacturers. Materials and Methods: For single composite resin samples, 6 mm diameter and 4 mm thickness cylindrical samples were fabricated using Ceram-X mono (DENTSPLY DeTrey) and CIE $L^*a^*b^*$ values were measured with spectrophotometer. Same process was done for layering composite resin samples, making 3 dentinal shade samples, 4 mm thickness, for each shade using Ceram-X duo (DENTSPLY DeTrey) and enamel shade resins were layered in 2 mm thickness and CIE $L^*a^*b^*$ values were measured. These samples were ground to 0.2 mm thickness each time, and CIE $L^*a^*b^*$ values were measured to 1 mm thickness of enamel shade resin. Results: Color difference (${\Delta}E^*$) between single and layering composite resin was 1.37 minimum and 10.53 maximum when layering thicknesses were between 1 mm and 2 mm and 6 out of 10 same shade groups suggested by manufacturer showed remarkable color difference at any thickness (${\Delta}E^*$ > 3.3). Conclusion: When using Ceram-X mono and duo for composite resin restoration, following the manufacturer's instructions for choosing the shade is not appropriate, and more accurate information for Ceram-X duo is needed on the variation and expression of the shades depending on the thickness of the enamel.

• Journal of the korean academy of Pediatric Dentistry
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• v.40 no.4
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• pp.283-295
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• 2013

In this study, researchers tried to find the effect, if any, of aging treatment to the specimens with three different dentin bonding agents using MicroCT. One, 5th generation - [Adper$^{TM}$ Single bond Plus] and two 6th generation [AdheSE$^{(R)}$, Adper$^{TM}$ Prompt$^{TM}$ L-Pop$^{TM}$] dentin bonding agents were used in this study. Specimens were divided into 4 groups according to aging treatment method used. Group I : control group, Group II : thermocycled between $5^{\circ}C$ and $55^{\circ}C$ for 60 seconds dwell time 5,000 times, Group III : aged as Group II and artificially brushed 20,000 times, Group IV : aged as Group III and were stored in artificial saliva for 6 months. With Single bond Plus, Group II showed more microleakage than Group I (p < 0.05). Group II and Group III showed more microleakage than Group IV (p < 0.05). There were no statistically significant differences among the groups using AdheSE$^{(R)}$ and Prompt$^{TM}$ L-Pop$^{TM}$ (p > 0.05). Among Group I, AdheSE$^{(R)}$ showed more microleakage than Single bond Plus and Prompt$^{TM}$ L-Pop$^{TM}$ (p < 0.05). Among Group II, there were no statistically significant differences (p > 0.05). Among Group III, AdheSE$^{(R)}$ showed more microleakage than Single bond Plus and Prompt$^{TM}$ L-Pop$^{TM}$ (p < 0.05). Among Group IV, AdheSE$^{(R)}$ and Prompt$^{TM}$ L-Pop$^{TM}$ showed more microleakage than Single bond Plus (p < 0.05).

• Food Science and Biotechnology
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• v.15 no.5
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• pp.752-755
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• 2006

This study was carried out to investigate the effects of ash tree leaf extract (ALE) on acetaminophen (APAP)-induced hepatotoxicity in mice. Hepatoprotective effects were detected by biochemical analysis of hepatic enzymes and histopathological examination of the liver. BALB/c mice were divided into three groups: 'normal' control mice, APAP-treated control mice, and mice pretreated with ALE and treated with APAP. A single dose of APAP markedly increased levels of plasma aspartate aminotransferase (AST) and alanine aminotransferase (ALT). Light micrographs of liver cells stained with hematoxylin and eosin showed that APAP induced severe centrilobular necrosis, degeneration, and infiltration by inflammatory cells. Moreover, APAP caused the numbers of TUNEL-positive hepatocytes to increase and caused glycogen content to decrease as observed by Periodic acid-Schiff stain. However, pretreatment with ALE for 7 days prior to the administration of APAP significantly decreased plasma levels of AST and ALT. Histological findings demonstrated that ALE pretreatment alleviated APAP-induced liver damage, and induced the regeneration of liver tissue and restoration of glycogen. These results indicate that ash tree leaf extract exerts a protective effect against APAP-hepatotoxicity induced injury.

• The Korea Journal of Herbology
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• v.22 no.2
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• pp.163-168
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• 2007

Objectives : This study was designed to investigate effects of Sayeoksanhap-Pyeongweisan-Gambang (SPG) on gene expression in rats damaged by CCl4 Methods : We investigated the effects of SPG on gene expression in terms of microarray methods in rat liver which were obtained from rats damaged by CCl4. Results : Decreased gene expressions, which were induced by single injection of CCl4, were restored to those in normal rats by administration of SPG or herbal acupuncture. In acupuncture group, gene expressions were restored by 80% of those in control group. In oral administration group and combination group, gene expressions were restored above 90% of those in cuntrol group. Conclusion : These results suggest that oral administraion of SPG was useful to protect liver against CCl4 by its restoration of gene expressions in liver resected from rat damaged by CCl4.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.434-437
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• 2005

Chemical Mechanical Polishing (CMP) has become an essential step in the overall semiconductor wafer fabrication technology. In general, CMP is a surface planarization method in which a silicon wafer is rotated against a polishing pad in the presence of slurry under pressure. The polishing pad, generally a polyurethane-based material, consists of polymeric foam cell walls, which aid in removal of the reaction products at the wafer interface. It has been found that the material removal rate of any polishing pad decreases due to the so-called 'pad glazing' after several wafer lots have been processed. Therefore, the pad restoration and conditioning has become essential in CMP processes to keep the urethane polishing pad at the proper friction coefficient and to allow effective slurry transport to the wafer surface. Diamond pad conditioner employs a single layer of brazed bonded diamond crystals. Due to the corrosive nature of the polishing slurry required in low pH metal CMP such as copper, it is essential to minimize the possibility of chemical interaction between very low pH slurry (pH <2) and the bond alloy. In this paper, we report an exceptional protective coated conditioner for in-situ pad conditioning in low pH Cu CMP process. The protective Cr-coated conditioner has been tested in slurry with pH levels as low as 1.5 without bond degradation.

• Journal of Korea Multimedia Society
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• v.13 no.11
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• pp.1621-1629
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• 2010

This paper presents an improved fast MSRCR algorithm that MSRs are commonly adopted at tone mapping in color vision. Conventional MSRs consist of three SSRs, which use three Gaussian functions with different scales as those surround ones. This convolution processes require much computation load. Therefore, the proposed algorithm adopts a hierarchical discrete correlation which is equivalent to Gaussian function and the Retinex process is only applied to the luminance channel in order to get a fast processing. A simple color preservation scheme is applied to the Retinex output from the luminance channel in the proposed MSRCR algorithm. Experimental results show that the proposed algorithm required less number of oprations and computation time about 1/9.5 and 1/3.5 times, respectively, than those of the simplest MSR and was equivalent to conventional MSRs.

• Journal of the Korean Wood Science and Technology
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• v.46 no.4
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• pp.402-414
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• 2018

Species identification of wood provides important information for archaeology, restoration of cultural assets, preventing illegal logging, and more. Wood species are usually identified based on their anatomical features with the use of a microscope. However, this method may not be able to distinguish between anatomically similar species or subspecies. To overcome this problem, wood species need to be identified at the molecular level using DNA sequencing. However, unlike living plant cells, wood is difficult to pulverize using a mortar, and DNA extraction from dried wood is challenging. To solve these problems, we propose a pretreatment method in which wood is pulverized using 60-grit sandpaper and hydrated with water for 2 days. Using this method, we were able to stably amplify the rpoB gene from the extracted DNA of Pinus rigida. In addition, sequence analysis of the rpoB gene revealed six single nucleotide polymorphisms (SNPs), which classified the rpoB sequences in the genus Pinus into five groups. Our data indicate that although these SNPs were not suitable for species identification, they can potentially be used to determine the origin of different wood subspecies or individual samples of wood.