• Journal of the Korean Society for Marine Environment & Energy
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• v.7 no.4
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• pp.192-198
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• 2004

A numerical method is developed to solve a two-dimensional diffraction problem for a body located in a sediment pocket where a heavier muddy water is trapped. In the present study, the wave exciting forces acting on a submerged body in the water-sediment interface by an incident wave is investigate. It is assumed that the heavier mud is trapped locally in a sediment pocket. A mathematical formulation is made in the scope of the potential theory. The fluid is assumed to be inviscid, incompressible and its motion irrotational. The boundary conditions on the unknown free surface and interface are linearized. As a method of solution, the localized finite-element method is adopted. In the method, the computation domain is reduced by utilizing the complete set of analytic solutions known in the infinite subdomain to be truncated by introduction of an appropriate juncture conditions. The main advantage of this method is that any complex geometry of the boundaries can be easily accommodated. Computations are carried out for mono-chromatic plane progressive surface waves normally incident on the domain. Numerical results are compared with those obtained by Lassiter based on Schwingers variational method. Good Agreements are obtained in general. Another numerical computations are made for the cases with and without a body in the sediment pocket.

• Journal of Korean Ophthalmic Optics Society
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• v.6 no.2
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• pp.71-75
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• 2001

In this paper, a three-dimensional measuring system of thermoluminescence(TL) spectra based on temperature, wavelength and luminescence intensity was introduced. The system was composed of a spectrometer, temperature control unit for thermal stimulation, photon detector and personal computer for control the entire system. Temperature control was achieved by using feedback to ensure a linear-rise in the sample temperature. Digital multimeter(KEITHLEY 195A) measures the electromotive force of Copper-Constantan thermocouple and then transmits the data to the computer through GPIB card. The computer converts this signal to temperature using electromotive force-temperature table in program, and then control the power supply through the D/A converter. The spectrometer(SPEX 1681) is controlled by CD-2A, which is controlled by the computer through RS-232 communication port. For measuring the luminescence intensity during the heating run, the electrometer(KEITHLEY 617) measures the anode current of photomultiplier tube(HAMAMATSU R928) and transmits the data to computer through the A/D converter. And, we measured and analyzed thermoluminescence of $CaSO_4$ : Dy, P using the system. The measuring range of thermoluminescence spectra was 300K-575K and 300~800 nm, $CaSO_4$ : Dy. P was fabricated by the Yamashita's method in Korea Atomic Energy Research Institute(KAERI) for radiation dosimeter. Thermoluminesce spectra of the $CaSO_4$ : Dy, P consist of two main peak at temperature of $205^{\circ}C$, wavelength 476 nm and 572 nm and with minor ones at 658 nm and 749 nm.

• The Korean Journal of Pharmacology
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• v.27 no.2
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• pp.135-144
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• 1991

Using T-lymphocytes obtained from rat peripheral blood, we found that the 44kD/pI6.8 protein was the major phosphoprotein of T-lymphocytes under basal condition, and that the 44kD/pI6.3 protein was a new phosphoprotein appeared in T-lymphocytes stimulated with ${\beta}-agonist$. The phosphorylation of the 44kD/pI6.3 protein was also induced by forskolin but inhibited by H-8 pretreatment. To clarify the character of the 44kD/pI6.3 protein, we used Con-A and kinase inhibitors, H-7 and W-7. Con-A stimulation induced phosphorylation of 44kD/pI 6.3 protein but that was inhibited by W-7 pretreatment. The phosphorytation of 44kD/pI6.3 protein was not induced by the PKC activator, PMA. Instead, the phosphorylation of 44kD/pI6.8 protein was reduced by H-7, a PKC inhibitor. From the above results,it can be concluded that the 44kD/pI6.3 protein can be a common substrate for A-kinase and CaM kinase. The two dimensional tryptic peptide mapping revealed that the 44kD/pI6.8 and 44kD/pI6.3 proteins are different.

• The Korean Journal of Physiology and Pharmacology
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• v.21 no.5
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• pp.531-546
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• 2017

Activation of Toll-like receptor-4 (TLR-4) in articular chondrocytes increases the catabolic compartment and leads to matrix degradation during the development of osteoarthritis. In this study, we determined the proteomic and genomic alterations in human chondrocytes during lipopolysaccharide (LPS)-induced inflammation to elucidate the underlying mechanisms and consequences of TLR-4 activation. Human chondrocytes were cultured with LPS for 12, 24, and 36 h to induce TLR-4 activation. The TLR-4-induced inflammatory response was confirmed by real-time PCR analysis of increased interleukin-1 beta ($IL-1{\beta}$), interleukin-6 (IL-6), and tumor necrosis factor alpha ($TNF-{\alpha}$) expression levels. In TLR-4-activated chondrocytes, proteomic changes were determined by two-dimensional electrophoresis and matrix-assisted laser desorption/ionization-mass spectroscopy analysis, and genomic changes were determined by microarray and gene ontology analyses. Proteomics analysis identified 26 proteins with significantly altered expression levels; these proteins were related to the cytoskeleton and oxidative stress responses. Gene ontology analysis indicated that LPS treatment altered specific functional pathways including 'chemotaxis', 'hematopoietic organ development', 'positive regulation of cell proliferation', and 'regulation of cytokine biosynthetic process'. Nine of the 26 identified proteins displayed the same increased expression patterns in both proteomics and genomics analyses. Western blot analysis confirmed the LPS-induced increases in expression levels of lamin A/C and annexins 4/5/6. In conclusion, this study identified the time-dependent genomic, proteomic, and functional pathway alterations that occur in chondrocytes during LPS-induced TLR-4 activation. These results provide valuable new insights into the underlying mechanisms that control the development and progression of osteoarthritis.

• The Korean Journal of Pesticide Science
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• v.10 no.1
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• pp.7-14
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• 2006

Three-dimensional quantitative structure-activity relationships (3D-QSARs) on the herbicidal activities against in-vitro pre-emergence rice plant (Oryza sativa L.) and barnyard grass (Echinochloa crus-galli) by new 5-benzofuryl-2-[1-(alkoxyimino)alkyl]-3-hydroxycyclohex-2-en-1-one derivatives were studied quantitatively using comparative molecular similarity indices analysis (CoMSIA) methodology. The optimized CoMSIA model(A5: $r^2_{cv.}=0.569$ & $r^2_{ncv.}=0.941$) for rice plant exhibited a good correlation with steric (31.6%) and hydrophobic (39.7%) factors of the substrate molecules, and the model (B4: $r^2_{cv.}=0.569$ & $r^2_{ncv.}=0.941$) for barnyardgrass exhibited a good correlation with electrostatic (46.7%) and H-bond acceptor field (30.8%), respectively. The predicted $R_1=SF_5,\;R_2=R_3=R_4=H(P1)$ substituent (Rice plant: $pI_{50}=4.84$ & Barnyardgrass: $pI_{50}=7.21$, ${\Delta}pI_{50}=2.37$) by the model (B4) not only exhibited to the highest herbicidal activity against barnyardgrass, but also exhibited to the highest selecticity between two plants.

• Journal of Korea Multimedia Society
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• v.8 no.10
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• pp.1369-1382
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• 2005

Vehicle segmentation, which extracts vehicle areas from road scenes, is one of the fundamental opera tions in lots of application areas including Intelligent Transportation Systems, and so on. We present a vehicle segmentation approach for still images captured from outdoor CCD cameras mounted on the supporting poles. We first divided the input image into a set of two-dimensional grids and then calculate the feature values of the edges for each grid. Through analyzing the feature values statistically, we can find the optimal rectangular grid area of the vehicle. Our preprocessing process calculates the statistics values for the feature values from background images captured under various circumstances. For a car image, we compare its feature values to the statistics values of the background images to finally decide whether the grid belongs to the vehicle area or not. We use dynamic programming technique to find the optimal rectangular gird area from these candidate grids. Based on the statistics analysis and global search techniques, our method is more systematic compared to the previous methods which usually rely on a kind of heuristics. Additionally, the statistics analysis achieves high reliability against noises and errors due to brightness changes, camera tremors, etc. Our prototype implementation performs the vehicle segmentation in average 0.150 second for each of $1280\times960$ car images. It shows $97.03\%$ of strictly successful cases from 270 images with various kinds of noises.

• Journal of Microbiology and Biotechnology
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• v.25 no.2
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• pp.152-161
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• 2015

CodY is a highly conserved protein in low G+C gram-positive bacteria that regulates genes involved in sporulation and stationary-phase adaptation. Bacillus thuringiensis is a grampositive bacterium that forms spores and parasporal crystals during the stationary phase. To our knowledge, the regulatory mechanism of CodY in B. thuringiensis is unknown. To study the function of CodY protein in B. thuringiensis, BMB171codY^- was constructed in a BMB171 strain. A shuttle vector containing the ORF of cry1Ac10 was transformed into BMB171 and BMB171codY^-, named BMB171cry1Ac and BMB171codY^-cry1Ac, respectively. Some morphological and physiological changes of codY mutant BMB171codY^-cry1Ac were observed. A comparative proteomic analysis was conducted for both BMB171codY^-cry1Ac and BMB171cry1Ac through two-dimensional gel electrophoresis and MALDI-TOF-MS/MS analysis. The results showed that the proteins regulated by CodY are involved in microbial metabolism, including branched-chain amino acid metabolism, carbohydrate metabolism, fatty acid metabolism, and energy metabolism. Furthermore, we found CodY to be involved in sporulation, biosynthesis of poly-β-hydroxybutyrate, growth, genetic competence, and translation. According to the analysis of differentially expressed proteins, and physiological characterization of the codY mutant, we performed bacterial one-hybrid and electrophoretic mobility shift assay experiments and confirmed the direct regulation of genes by CodY, specifically those involved in metabolism of branched-chain amino acids, ribosomal recycling factor FRR, and the late competence protein ComER. Our data establish the foundation for in-depth study of the regulation of CodY in B. thuringiensis, and also offer a potential biocatalyst for functions of CodY in other bacteria.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.11
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• pp.2103-2108
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• 2017

For n points $p_i$ on the m-dimensional plane $R^m$ and a fixed range r, consider a set $T_i$ containing points the distances from $p_i$ of which are less than or equal to r. In case m=1, $T_i$ is an interval on a line, it is a circle on a plane when m=2. For the vertices corresponding to the sets $T_i$, there is an edge between the vertices if the two sets intersect. Then this graph is called an intersection graph G. For m=1 G is called a proper interval graph and for m=2, it is called an unit disk graph. In this paper, we are concerned in the intersection graph G(r) when r changes. In particular, we consider the problem to find the minimum r such that G(r)is connected. For this problem, we propose an O(n) algorithm for the proper interval graph and an $O(n^2{\log}\;n)$ algorithm for the unit disk graph. For the dynamic environment in which the points on a line are added or deleted, we give an O(log n) algorithm for the problem.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.5A
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• pp.459-468
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• 2006

Current routing in sensor networks focuses on finding methods for energy-efficient route setup and reliable relaying of data from the sensors to the sink so that the lifetime of the network is maximized. The existing routing protocols do not have routing tables to determine a path when packets are transferred. A sensor network by a routing table increases a cost of maintaining and updating a path, because sensor nodes have characteristics to be mobile and constrained capacity and resources. This paper proposes a new routing algorithm by broadcasting a bitmap in order to reduce the number of messages transferred when routing paths are established. Each node has a routing table with a bitmap, which contains link information. A bitmap is formed two-dimensional array, which consists of each row and column represented with a bit. The node only updates its own bitmap if it receives a bitmap from another adjacent nodes after the broadcasting. There by, each node has a bitmap with partial links information not total links information on the network. The proposed routing algorithm reduces the number of messages for routing establishment at least 10% compared with the previous algorithms.

• Korean Journal of Applied Biomechanics
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• v.14 no.2
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• pp.27-40
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• 2004

The objective of this study is to identify the kinematic variables of giant swing backward to handstand as well as individual variations of each athlete performing this skill, which in turn will provide the basis for developing suitable training methods and for improving athlete's performance in actual games. For this end, 3 male athletes, members of the national team, who are in ${\Box}{\Box}H{\Box}{\Box}$ University, have been randomly chosen and their giant swing backward to handstand performance was recorded using two digital cameras and analyzed in 3 dimensional graphics. This study came to the following conclusion. 1. Proper time allocation for giant swing backward to handstand are: Phase 1 should provide enough time to attain energy for swing track of a grand round movement. The phase 3 is to throw the body up high in the air and stay in the air as long as possible to smoothen up the transition to the next stage and the phase 4 should be kept short with the moment arm coefficient of the body reduced. 2. As for appropriate changes of locations of body center, the phase 1 should be comprised of horizontal, perpendicular, compositional to make up a big rotational radius. Up to the Phase 3 the changes of displacements of vertical locations should be a good scale and athlete's body should go up high quickly to increase the perpendicular climbing power 3. When it comes to the speed changes of body center, the vertical and horizontal speed should be spurred by the reaction of the body in Phase 2 and Phase 3. In the Phase 4, fast vertical speed throws the body center up high to ensure enough time for in-the-air movement. 4. The changes of angles of body center are: in Phase 2, shoulder joint is stretching and coxa should be curved up to utilize the body reaction. In the Phase 4, shoulder joint and coxa should be stretched out to get the body center as high as possible in the air for stable landing. 5. The speeds of changes in joints angles are: in the Phase 2 should have the speed of angles of shoulder joints increase to get the body up in the air as quickly as possible. The Phase 3 should have the speed of angles in shoulder joint slow down, while putting the angles of a knee joint up to speed as quickly as possible to ensure enough time for in-the-air movement.