• Title/Summary/Keyword: SPB

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A Search for New Variable Stars in the Open Cluster NGC 129 using a Small Telescope (소형망원경을 이용한 산개성단 NGC 129 영역의 변광성 탐사)

  • Lee, Eun-Jung;Jeon, Young-Beom;Lee, Ho;Park, Hong-Suh
    • Journal of the Korean earth science society
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    • v.28 no.1
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    • pp.87-104
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    • 2007
  • As part of the SPVS (Short-Period Variability Survey) which is a wide-field $(90'{\times}60')$ photometric monitering program at Bohyunsan Optical Astronomy (BOAO), we performed V band time-series CCD photometric observations ofthe young open cluster NGC 129 for 11 nights between October 12, 2004 and November 3, 2005 using the 155mm refractor equipped with $3K{\times}2K$ CCD camera. From the observation we obtained 2400 V band CCD frames and color-magnitude diagram of the cluster. To transform instrumental magnitude to standard magnitude, we applied ensemble normalization technique to all observed time-series data. After the photometric reduction process, we examined variations of 9537 stars. As a result, sixty six of the new variable stars were discovered. To determine the periods of the sevariables, we used DFT(Discrete Fourier Transform) and phase-matching technique. According to light curve shape, period, amplitude and the position on a C-M diagram, we classified these variables as 9 SPB type, 9 ${\delta}$ Scuti type, 29 eclipsing, 17 long term variables. However, two of them were not classified. From this study, we learned that small telescopes could be a very useful tool to observe variable stars in the open cluster in survey program.

Analysis of Noise Characteristics of Double and Single-layered Porous Pavement with CPX Method -National Route 1, Sejong-Si Section- (CPX방법에 의한 복층 및 단층 다공성포장의 소음특성 분석 -국도 1호선 세종시 구간-)

  • Yoo, In-Kyoon;Lee, Su-Hyung;Han, Dae-Seok
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.10
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    • pp.55-63
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    • 2020
  • Road traffic noise is a major complaint. Porous pavement (PP) has been proposed as an effective method for reducing road traffic noise, but it has not been applied much due to the lack of quantitative evaluation. In this study, the noise reduction of single-layer porous pavement (SLPP) and double-layer porous pavement (DLPP) was evaluated. The noise was measured using the CPX method, and the driving speed was measured every 10km/h from 50km/h to 80km/h. The differences in noise level between the two PPs were statistically significant. The driving speed had no significant effect on the difference in noise between the two PPs. The DLPP showed a 6.6dB(A) reduction in average and a 6.3dB(A) reduction at the 95% confidence level compared to the SLPP. Reducing noise by 5dB(A) is equivalent to reducing traffic to 1/3 or lowering the vehicle's speed to 1/2. Sensitively, it is possible to recognize a 3dB(A) and 5dB(A) difference. The DLPP and SLPP were very effective in reducing traffic noise.

Pharmacophore Modeling, Virtual Screening and Molecular Docking Studies for Identification of New Inverse Agonists of Human Histamine H1 Receptor

  • Thangapandian, Sundarapandian;Krishnamoorthy, Navaneethakrishnan;John, Shalini;Sakkiah, Sugunadevi;Lazar, Prettina;Lee, Yu-No;Lee, Keun-Woo
    • Bulletin of the Korean Chemical Society
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    • v.31 no.1
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    • pp.52-58
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    • 2010
  • Human histamine H1 receptor (HHR1) is a G protein-coupled receptor and a primary target for antiallergic therapy. Here, the ligand-based three-dimensional pharmacophore models were built from a set of known HHR1 inverse agonists using HypoGen module of CATALYST software. All ten generated pharmacophore models consist of five essential features: hydrogen bond acceptor, ring aromatic, positive ionizable and two hydrophobic functions. Best model had a correlation coefficient of 0.854 for training set compounds and it was validated with an external test set with a high correlation value of 0.925. Using this model Maybridge database containing 60,000 compounds was screened for potential leads. A rigorous screening for drug-like compounds unveiled RH01692 and SPB00834, two novel molecules for HHR1 with good CATALYST fit and estimated activity values. The new lead molecules were docked into the active site of constructed HHR1 homology model based on recently crystallized squid rhodopsin as template. Both the hit compounds were found to have critical interactions with Glu177, Phe432 and other important amino acids. The interpretations of this study may effectively be deployed in designing of novel HHR1 inverse agonists.

Molecular genetic analysis of phytochelatin synthase genes in Arabidopsis

  • Ha, Suk-Bong
    • Proceedings of the Botanical Society of Korea Conference
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    • 2002.04a
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    • pp.62-72
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    • 2002
  • This study has investigated the biosynthesis and function of the heavy metal binding peptides, the phytochelatins, in plants. PCs are synthesised enzymatically from glutathione by the enzyme PC synthase in the presence of heavy metal ions. Using Arabidopsis thaliana as a model organism cadmium-sensitive, phytochelatin-deficient mutants have been isolated and characterised in previous studies. The cadl mutants have wildtype levels of glutathione, are PC deficient and lack PC synthase activity. Thus, the CADl gene has been proposed to encode PC synthase. The CADl gene was isolated by a positional cloning strategy The gene was mapped and a candidate identified. Each of four cadl mutants had a single base pair change in the candidate gene and the cadmium-sensitive, cadl phenotype was complemented by the candidate gene. This demonstrated the CADl gene had been cloned. A homologous gene in the fission yeast, Schizosaccharomyces pombe was identified through database searches. A targeted-deletion mutation of this gene was constructed and the mutant, like cadl mutants of Arabidopsis, was cadmium-sensitive and PC-deficient. A comparison of the redicted amino acid sequences reveals a highly conserved N-terminal region Presumed to be the catalytic domain and a variable C-terminal region containing multiple Cys residues proposed to be involved in activation of the enzyme by metal ions. Similar genes were also identified in animal species. The Arabidopsis CADl/AtPCSl and S. pombe SpbPCS genes were expressed in E. coli and were shown to be sufficient for glutathione-dependent, heavy metal activate PC synthesis in vitro, thus demonstrating these genes encode PC synthase enzymes. Using RT-PCR, AtPCSl expression appeared to be independent of Cd exposure. However, at higher levels of Cd exposure a AtPCSl-CUS reporter gene construct appeared to be more highly expressed. Using the reporter gene construct, AtPCSl was expressed most tissues. Expression appeared to be greater in younger tissues and same higher levels of expression was observed in some regions, including carpels and the base of siliques. AtPCS2 was a functional gene encoding an active PC synthase. However, its Pattern of expression and the phenotype of a mutant (or antisense line) have not been determined. Assuming the gene is functional then it has clearly been maintained through evolution and must provide some selective advantage. This implies that, at least in some cells or tissue, it is likely to be the dominant PC synthase expressed. This remains to be determined

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An analysis of storage and runoff reduction characteristics using planter box in architectural LID system (건축형 LID 시스템에서 Planter Box를 활용한 저류 및 유출저감 특성 분석)

  • Kim, Byung Sung;Kim, Jae Moon;Baek, Jong Seok;Shin, Hyun Suk
    • Journal of Korea Water Resources Association
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    • v.52 no.3
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    • pp.219-226
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    • 2019
  • Recently, research about Low-Impact Development (LID) techniques has been expanded due to problems with the effects of climate change and urbanization that have been increasing. LID technology is used to control flood damage environmentally to reduce runoff and is reduce runoff on city also restore into previous water circulation system from present developed city. However, studies about quantitative data of LID techniques are insufficient. Therefore in this study, the Curve Number (CN) was calculated with the Planter Box, which is storage type LID technology to conduct the water circulation (infiltration, runoff, overflow) analysis. Rainfall intensity scenario (60.4 mm/hr, 83.1 mm/hr, 97.4 mm/hr, 108.2 mm/hr) about water circulation analysis of Planter Box is selected on the basis of probable rainfall intensity table. According to the experimental results, the storage rate of rainwater in Building Planter Box and Street Planter Box was 43.5% to 52.9% and 33.4% to 39%, respectively. In addition, CN value is estimated to 83 at the Planter box and the runoff reduction effect by applying Horton's infiltration capacity curve showed on 51% to 98%.