• KSII Transactions on Internet and Information Systems (TIIS)
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• 제9권10호
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• pp.4108-4125
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• 2015

This paper presents a scalable coding method for depth images by considering the quality of synthesized images in virtual views. First, we design a new edge detection algorithm that is based on calculating the depth difference between two neighboring pixels within the depth map. By choosing different thresholds, this algorithm generates a scalable bit stream that puts larger depth differences in front, followed by smaller depth differences. A scalable scheme is also designed for coding depth pixels through a layered sampling structure. At the receiver side, the full-resolution depth image is reconstructed from the received bits by solving a partial-differential-equation (PDE). Experimental results show that the proposed method improves the rate-distortion performance of synthesized images at virtual views and achieves better visual quality.

• 한국간호교육학회지
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• 제24권4호
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• pp.391-405
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• 2018

Purpose: The purpose of this study was to integrate and synthesize findings from qualitative studies exploring male students' experiences of adapting to nursing education programs so as to obtain further understanding of the phenomenon. Methods: The meta-synthesis process was primarily guided by Noblit and Hare's approach, which consists of four stages including searching, appraisal of an individual study's quality, data extraction for analysis, and meta-synthesizing the results. Results: Findings from the literature reviewed were synthesized into six themes: 1) extraordinary choice based on job stability and gender scarcity; 2) unexpected feeling of marginalization as minority far apart from the mainstream; 3) assimilation and negotiation for relational adaptation through perspective shift; 4) fortifying the vision and identity as nursing students by meaning making for adapting to the nursing major; 5) mutual support among colleague male students; and 6) serving in the military as way of hiding out and achieving maturation. Conclusion: The findings illustrate that nursing education programs need practical changes promoting male students' adaptation to the program itself as well as preparation to be a professional nurse in the future.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송∙미디어공학회 2020년도 추계학술대회
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• pp.252-255
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• 2020

Unsupervised deep learning methods have shown impressive results for the challenging monocular depth estimation task, a field of study that has gained attention in recent years. A common approach for this task is to train a deep convolutional neural network (DCNN) via an image synthesis sub-task, where additional views are utilized during training to minimize a photometric reconstruction error. Previous unsupervised depth estimation networks are trained within a fixed depth estimation range, irrespective of its possible range for a given image, leading to suboptimal estimates. To overcome this suboptimal limitation, we first propose an unsupervised adaptive depth estimation method guided by minimum and maximum (min-max) depth priors for a given input image. The incorporation of min-max depth priors can drastically reduce the depth estimation complexity and produce depth estimates with higher accuracy. Moreover, we propose a novel network architecture for adaptive depth estimation, called the AdaMM-DepthNet, which adopts the min-max depth estimation in its front side. Intensive experimental results demonstrate that the adaptive depth estimation can significantly boost up the accuracy with a fewer number of parameters over the conventional approaches with a fixed minimum and maximum depth range.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 2003년도 Annual Meeting of KSAP : International Symposium on Pharmaceutical and Biomedical Sciences on Obesity
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• pp.80-80
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• 2003

Insulin-dependent or Type 1 diabetes mellitus (IDDM) has been associated with an increased severity of periodontal disease. Since periodontal ligament (PDL) cells play a significant role in maintenance and regeneration of mineralized tissue, the success of procedures, such as guided tissue regeneration, is directly related to the ability of these cells to augment mineralized tissue. In this study, we investigated the time- and dose-dependent effect of high glucose on the proliferation and collagen synthesis of human periodontal ligament (PDL) cells. PDL cells were treated with high glucose (22mM, 33mM, 44mM) for 1 or 2 days. High glucose significantly inhibited proliferation of PDL cells as a time- and dose-dependent manner as evidenced by MTT assay. PDL cells were cultured in high glucose media (22mM, 33mM, 44mM) for 24 h. The ratio of collagen content to total protein was evaluated, and the gene expression of type I collagen was assessed by RT - PCR. The high concentration of glucose inhibited collagen synthesis, a marker of bone formation activity. This study indicated high glucose concentration could alter the metabolism of periodontal ligament cell, leading to alveolar bone destruction.

• Natural Product Sciences
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• 제17권3호
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• pp.198-201
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• 2011

Tyrosinase is one of the important enzymes in the mammalian melanin synthesis. In the process of melanin synthesis, tyrosine is oxidized to DOPA (3,4-dihydroxyphenylalanine), and DOPA is further oxidized to dopaquinone. Tyrosinase is an enzyme catalyzing this oxidation of tyrosine, so chemicals that inhibit the activity of tyrosinase can be used as skin whitening agents. In this study, we isolated five constituents from the 80% MeOH extract of Morus bombycis cortex by bioactivity-guided fractionation. We performed mushroom tyrosinase inhibition assay. As a result, 7,2',4'-trihydroxyflavanone (1), 2',4',2,4,-tetrahydroxychalcone (2), and oxyresveratrol (3) showed the more potent inhibitory effect compared to kojic acid, a well-known skin whitening agent with antityrosinase effect. Moracinoside M (4) and moracin M-3'-O-${\beta}$-D-glucopyranoside (5) also showed the moderate tyrosinase inhibitory activities.

• Archives of Pharmacal Research
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• 제27권12호
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• pp.1220-1225
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• 2004

The overproduction of nitric oxide (NO) by inducible nitric oxide synthase (iNOS) is known to be responsible for vasodilation and hypotension observed in septic shock and inflammation. Inhibitors of iNOS, thus, may be useful candidates for the treatment of inflammatory diseases accompanied by overproduction of NO. In the course of screening oriental anti-inflammatory herbs for the inhibitory activity of NO synthesis, a crude methanolic extract of Curcuma zedoaria exhibited significant activity. The activity-guided fractionation and repetitive chromatographic procedures with the EtOAc soluble fraction allowed us to isolate three active compounds. They were identified as 1,7-bis (4-hydroxyphenyl)-1,4,6-heptatrien-3-one (1), procurcumenol (2) and epiprocurcumenol (3) by spectral data analyses. Their concentrations for the 50% inhibition of NO production $(IC_{50})$ in lipopolysaccharide (LPS)-activated macrophages were 8, 75, 77 ${\mu}M$, respectively. Compound 1 showed the most potent inhibitory activity for NO production in LPS-activated macrophages, while the epimeric isomers, compound 2 and 3 showed weak and similar potency. Inhibition of NO synthesis by compound 1 was very weak when activated macrophages were treated with 1 after iNOS induction. In the immunoblot analysis, compound 1 suppressed the expression of iNOS in a dose-dependent manner. In summary, 1,7-bis (4-hydroxyphenyl)-1,4,6-heptatrien-3-one from Curcuma zedoaria inhibited NO production in LPS-activated macrophages through suppression of iNOS expression. These results imply that the traditional use of C. zedoaria rhizome as anti-inflammatory drug may be explained at least in part, by inhibition of NO production.

• 생약학회지
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• 제30권2호
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• pp.173-176
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• 1999

Bioassay-guided fractionation of a $H_2O$ extract of the roots of Gentiana scabra has furnished 5-(hydroxymethyl)-2-furfural (1) as an inhibitory compound for nitric oxide (NO) production in murine macrophage RAW 264.7 cells stimulated with $interferon-{\gamma}$ plus lipopolysaccharide. Compound 1 showed the moderate inhibition of NO production with $IC_{50}$ value of $803\;{\mu}M$.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1993년도 한국자동제어학술회의논문집(국내학술편); Seoul National University, Seoul; 20-22 Oct. 1993
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• pp.330-335
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• 1993

This paper presents an efficient solution for a class of forbidden state problems by introducing a cyclic timed controlled marked graphs (TCMG's), a special class of timed controlled Petri nets (TCPN's) as a model of a class of discrete event systems (DES's). The state feedback control is synthesized, which is maximally permissive while guaranteeing the forbidden states will be avoided. The practical applications or tire theoretical results for an automated guided vehicle (ACV) coordination problem in a flexible manufacturing facility is illustrated.

• Bulletin of the Korean Chemical Society
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• 제26권3호
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• pp.447-450
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• 2005

The crude methanol extract of the fruits of Amomum tsao-ko (Zingiberaceae) showed cytotoxic activity. Bioactivity-guided separation led to the isolation of a diarylheptanoid, tsaokoarylone [7-(4-hydroxy-3-methoxyphenyl)-1-(4-hydroxyphenyl)-hepta-4E,6E-dien-3-one] (2). 2 showed cytotoxicity at 4.9 and 11.4 $\mu$g/mL ($IC_{50}$) against human nonsmall cell lung cancer A549 and human melanoma SK-Mel-2, respectively, determined by SRB colorimetric method. During purification-(4-hydroxyphenyl)-4-hydroxyhexan-2-one (4) together with three known diarylheptanoids was also isolated. Their structures were determined from interpretation of spectroscopic data (IR, UV, MS, and NMR) and synthesis confirmed the structure of 2.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제12권8호
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• pp.3842-3855
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• 2018

A novel image completion method is proposed that uses the advantage of planar structural information to fill corrupted portions of an image. First, in estimating parameters of the projection plane, the image is divided into several planes, and their planar structural information is analyzed. Second, in calculating the a priori probability of patch and patch offset regularity, this information is converted into a constraint condition to guide the process of filling the hole. Experimental results show that the proposed algorithm is fast and effective, and ensures the structure continuity of the damaged region and smoothness of the texture.