• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.24 no.3
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• pp.324-330
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• 2013

This paper presented measurement results of scattering characteristics of dielectric barrier discharge (DBD) plasma at atmospheric pressure. In this paper, plasma actuator is fabricated by parallel connecting of basic configuration of DBD plasma actuator, then plasma could be generated by applying 14 kV, 4 kHz of high voltage generator. In order to measure the scattering characteristics of DBD plasma, in this paper, two horn antennas and vector network analyzer are used to compare the S-parameter. Because of the structure of fabricated plasma generator, different result is obtained as antenna polarization changes. When antenna polarization is parallel to electrodes of plasma generator, the scattered field is reduced by 2 dB in maximum. In addition, for parallel polarization case, PEC is set up behind the plasma generator to measure backward scattered field. When the observation angles are $40^{\circ}C$ and $60^{\circ}C$, the amount of reduced scattered field is 2 dB in maximum at 5 GHz.

• Preventive Nutrition and Food Science
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• v.21 no.1
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• pp.62-67
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• 2016

Green tea (Camellia sinensis) is one of the most popular beverages in the world and has been acknowledged for centuries as having significant health benefits. (-)-Epigallocatechin-3-gallate (EGCG) is the most abundant catechin in green tea, and it has been reported to have health benefit effects. Peroxisome proliferator-activated receptor ${\gamma}$ coactivator $(PGC)-1{\alpha}$ is a crucial regulator of mitochondrial biogenesis and hepatic gluconeogenesis. The objective of this study was to investigate whether EGCG from green tea can affect the ability of transcriptional regulation on $PGC-1{\alpha}$ mRNA expression in HepG2 cells and 3T3-L1 adipocytes. To study the molecular mechanism that allows EGCG to control $PGC-1{\alpha}$ expression, the promoter activity levels of $PGC-1{\alpha}$ were examined. The $PGC-1{\alpha}$ mRNA level was measured using quantitative real-time PCR. The -970/+412 bp of $PGC-1{\alpha}$ promoter was subcloned into the pGL3-Basic vector that includes luciferase as a reporter gene. EGCG was found to up-regulate the $PGC-1{\alpha}$ mRNA levels significantly with $10{\mu}mol/L$ of EGCG in HepG2 cells and differentiated 3T3-L1 adipocytes. $PGC-1{\alpha}$ promoter activity was also increased by treatment with $10{\mu}mol/L$ of EGCG in both cells. These results suggest that EGCG may induce $PGC-1{\alpha}$ gene expression, potentially through promoter activation.

• Korean Journal of Microbiology
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• v.51 no.3
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• pp.187-193
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• 2015

Candida (also known as Pseudozyma) antarctica lipase B (CAL-B) has been intensely studied in academic and industrial fields. However, the research related to its homologous enzymes has been rarely reported. In the current investigation, protein sequence similarity search of CAL-B has been conducted and six homologous protein sequences were identified. After the syntheses of their codon-optimized genes, the synthetic genes have been cloned into a periplasmic expression vector to express in Escherichia coli. Among six homologous sequences, four sequences were successfully expressed in E. coli. The hydrolytic activities of the expressed proteins towards 4-nitrophenyl acetate and 4-nitrophenyl butyrate were measured and compared with those of CAL-B to identify whether the expressed proteins work as a hydrolase. It has been revealed that the expressed proteins can hydrolyze the substrates and the specific activities were determined as $(1.3-30){\times}10^{-2}{\mu}mol/min/mg$, which are lower than those of CAL-B. Among these homologous enzymes, Pseudozyma hubeiensis SY62 exhibits the comparable enantioselectivity to that of CAL-B towards the hydrolysis of (${\pm}$)-1-phenylethyl acetate.

• Food Science of Animal Resources
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• v.38 no.2
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• pp.362-375
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• 2018

This study proposed a rapid microscopic examination method for pork freshness evaluation by using the self-assembled hyperspectral microscopic imaging (HMI) system with the help of feature extraction algorithm and pattern recognition methods. Pork samples were stored for different days ranging from 0 to 5 days and the freshness of samples was divided into three levels which were determined by total volatile basic nitrogen (TVB-N) content. Meanwhile, hyperspectral microscopic images of samples were acquired by HMI system and processed by the following steps for the further analysis. Firstly, characteristic hyperspectral microscopic images were extracted by using principal component analysis (PCA) and then texture features were selected based on the gray level co-occurrence matrix (GLCM). Next, features data were reduced dimensionality by fisher discriminant analysis (FDA) for further building classification model. Finally, compared with linear discriminant analysis (LDA) model and support vector machine (SVM) model, good back propagation artificial neural network (BP-ANN) model obtained the best freshness classification with a 100 % accuracy rating based on the extracted data. The results confirm that the fabricated HMI system combined with multivariate algorithms has ability to evaluate the fresh degree of pork accurately in the microscopic level, which plays an important role in animal food quality control.

• Molecular & Cellular Toxicology
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• v.4 no.2
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• pp.144-149
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• 2008

Despite versatile activity (cancericidal, antimicrobial, hypoxia inducible factor (HIF) inhibition, immune deactivation of DNA bis-intercalation agent, echinomycin, its specific mechanism has been elusive. Of these novel mechanisms, we reported that using human colon cancer cells (HT-29), apoptotic machinery induced by echinomycin might be dependent of caspase-3 pathway. Despite a partial enlightenment of prototypic signal path triggered by echinomycin, the role of Bcl-2 in this signaling pathway is unclear. To address this issue, we explored whether or not echinomycin would overcome the anti-apoptotic impact of Bcl-2 in HT-29 cells by the controlled Bcl-2 overexpression. Prior to this proof, we confirmed that echinomycin induces mitochondrial depolarization, then triggering the mitochondrial pathway of apoptosis with an involvement of upstream cas-pases-3. Transiently transfection with inactive Bax-DNA failed to prevent echinomycin-induced apoptosis in HT-29 cells. To dissect the role of Bcl-2 in echinomycin-induced apoptosis, HT-29 cells were transiently transfected with Bcl-2 DNA for overexpression and then treated with echinomycin for 24h. Combined analyses of DNA fragmentation and flow cytometric analysis clearly verified that echinomycin-induced apoptosis was drastically attenuated by Bcl-2 overexpression, whereas a control vector rarely affected echinomycin-induced apoptosis. Collectively, these data verify that Bcl-2 regulates echinomycin-induced apoptosis in HT-29 cells. To my knowledge, this is the first evidence that of diverse, structured minor groove binders (MGB), the prototypic echinomycin might control the apoptotic signaling via Bcl-2-mitochondrial pathway.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.10B
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• pp.1986-1994
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• 1999

In this paper, a semi-automatic approach is adopted to extract a semantic object from real-world video sequences human-aided segmentation for the first frame and automatic tracking for the remaining frames. The proposed algorithm has a hierarchical structure using watershed algorithm. Each hierarchy consists of 3 basic steps: First, seeds are extracted from the simplified current frame. Second, region growing bv a modified watershed algorithm is performed to get over-segmented regions. Finally, the segmented regions are classified into 3 categories, i.e., inside, outside or uncertain regions according to region probability values, which are acquired by the probability map calculated from an estimated motion-vector field. Then, for the remaining uncertain regions, the above 3 steps are repeated at lower hierarchies with less simplified frames until every region is classified into a certain region. The proposed algorithm provides prospective results in studio-quality sequences such as 'Claire', 'Miss America', 'Akiyo', and 'Mother and daughter'.

• Journal of the Korea Computer Graphics Society
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• v.4 no.1
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• pp.79-88
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• 1998

Till now there are several rendering models for water and simulating other fluids and their dynamics. Especially in order to generate a curved surface of flexible objects such as liquid and snow, the implicit metaball formulation is widely used in favor of its simplicity and flexibility. This paper proposes one excellent method for generating water droplets, which would be deformed in gravitation field. In previous works, a water droplet was simply represented by approximated curved surfaces of a symmetric metaball. Thus the final result of the rendered water droplet was far from a realistic droplet, because they do not consider the gravitational effect in droplets. We propose a new metaball model for rendering water droplets placed on an arbitrary surface considering the gravitation and friction between droplet and plate. Our new metaball model uses a new vector field isosurface function to control the basic scalar metaball with respect to the norm of gravitational force. In several experiments, we could render a photo-realistic water droplets with natural-looking shadows by applying ray-tracing.

• Journal of Korea Multimedia Society
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• v.15 no.4
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• pp.485-491
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• 2012

This paper proposes 'Coding Unit Tree' based on quadtree efficiently with motion vector to represent splitting information of a Coding Unit (CU) in HEVC. The new international video coding, High Efficiency Video Coding (HEVC), adopts various techniques and new unit concept: CU, Prediction Unit (PU), and Transform Unit (TU). The basic coding unit, CU is larger than macroblock of H.264/AVC and it splits to process image-based quadtree with a hierarchical structure. However, in case that there are complex motions in CU, the more signaling bits with motion information need to be transmitted. This structure provides a flexibility and a base for a optimization, but there are overhead about splitting information. This paper analyzes those signals and proposes a new algorithm which removes those redundancy. The proposed algorithm utilizes a type code, a dominant value, and residue values at a node in quadtree to remove the addition bits. Type code represents a structure of an image tree and the two values represent a node value. The results show that the proposed algorithm gains 13.6% bit-rate reduction over the HM-1.0.

• Journal of KIISE:Software and Applications
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• v.35 no.8
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• pp.522-528
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• 2008

Topic map typically provide information to user through the selection of topics, that is using only topic, association, occurrence on the first topicmap which is made by domain expert without regard to individual interests or context, for the purpose of supplementation for the weakness which is providing personalized topic map information, personalization has been studied for supporting user preference through preseting of customize, filtering, scope, etc in topic map. Nevertheless, personalization in current topicmap is not enough to user so far. In this paper, we propose a design of PTRS(personalized topicmap ranking system) & algorithm, using both user profile(click through data) and basic element of topic map(topic, association) on knowledge layer in specific domain topicmap, therefore User has strong point that is improvement of personal facilities to user through representation of ranked topicmap information in consideration of user preference using PTRS.

• 한국전산유체공학회:학술대회논문집
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• 2005.10a
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• pp.93-97
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• 2005

Air interlacing serves to protect the yarn against damage, strengthens inter-filament compactness or cohesion, and ensures fabric consistency. The air interlacing nozzle is used to introduce intermittent nips to a filament yarn so as to improve its performance in textile processing. This study investigates the effect of interlacing nozzle geometry on the interlacing process. The geometries of interlacing nozzles with multiple air inlets located across the width of a yarn channels are investigated. The basic interlacing nozzle is the yarn channel, with a perpendicular single air inlet in the middle. The yarn channel shapes are cross sections with semicircular or rectangular shapes. This paper presents three doubled sub air inlets with main air inlet and one of them is slightly inclined doubled sub air inlets with main air inlet. The compressed air coming out from the inlet hits the opposing wall of the yarn channel, divides into two branches, flows trough the top side of yarn channel, joins with the compressed air coming out from the sub air inlet and then creates two free jets at both ends of the yarn channel. The compressed air moves in the shape of two opposing directional vortices. The CFD-FASTRAN was used to perform steady simulations of impinging jet flow inside of the interlace nozzles. The vortical structure and the flow pattern such as pressure contour, particle traces, velocity vector plots inside of interlace nozzle geometry are discussed in this paper.