• Title/Summary/Keyword: STAR

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Proposition of Green Star for the Practice of Rio+20, and Application of Four Rivers Project (Rio+20의 실천을 위한 녹색별 제안과 4대강사업에서의 적용)

  • Koo, Ja-Kong;An, Hyo-Won
    • Journal of the Korea Organic Resources Recycling Association
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    • v.22 no.1
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    • pp.35-39
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    • 2014
  • The world has been interested in sustainable development and to be considered important the three values(Environmental Integrity, Economic Growth, Social expandability) of sustainability. Rio+20 conference was attention to "Green Economy", trying to solve for sustainable development. But Rio+20 proposed "The Future We Want", They can't solve it and it is regret. Also It is judged that Only three values of sustainability are limited to sustainable development. Five values; Green Star is suggested the answer for "The Future We Want". Four Rivers Project verified by Green Star, Green Star proposed new paradigm for sustainable development. And Expect the strong well-being country of Korea.

Metastatic Inhibitory and Radical Scavenging Efficacies of Saponins Extracted from the Brittle Star (Ophiocoma erinaceus)

  • Amini, Elaheh;Nabiuni, Mohammad;Baharara, Javad;Parivar, Kazem;Asili, Javad
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.11
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    • pp.4751-4758
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    • 2015
  • Echinodermata use saponins in chemical defense against pathogens and predators. The molecular mechanisms of antimetastatic effects of brittle star saponins are still unknown. The present study examined antioxidant capacity and invasive ability in HeLa carcinoma cells exposed to brittle star crude saponins. Discolorating methods with DPPH and ABTS and expression of SOD-2 with RT-PCR were used to estimate the antioxidant activity. The anti-invasive activity of extracted saponins was examined through adhesion of HeLa cells to extracellular matrix, wound healing and evaluation of the mRNA levels of MMP-2 and MMP-9 by real time-PCR. The results showed that extracted saponins had cytotoxicity against cervical cancer cells and ABTS and DPPH scavenging properties with $IC_{50}$ values of 604.5, $1012{\mu}g/ml$, respectively. Further, we found that, in wound healing assay, brittle star saponins could prevent invasion of HeLa cells in a concentration dependent manner. Furthermore, cell adhesion assay demonstrated blockage of cell attachment to extracellular matrix with an $IC_{50}$ concentration of $16.1{\mu}g/ml$. The significant dose dependent down regulation of MMP-2 and MMP-9 in treated cells demonstrated that isolated saponins can decline tumor metastasis in vitro. The brittle star saponins remarkably prevented cervical cancer invasion and migration associated with down regulation of matrix metalloproteinase expression. Therefore, saponins could be suggested as an anti-invasive candidate against cervical cancer and an antioxidant as well.

Discovery of an elliptical jellyfish galaxy with MUSE

  • Sheen, Yun-Kyeong;Smith, Rory;Jaffe, Yara;Kim, Minjin;Duc, Pierre-Alain;Ree, Chang Hee;Nantais, Julie;Candlish, Graeme;Yi, Sukyoung;Demarco, Ricardo;Treister, Ezequiel
    • The Bulletin of The Korean Astronomical Society
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    • v.42 no.2
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    • pp.46.2-46.2
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    • 2017
  • We will present a discovery of an elliptical jellyfish galaxy in Abell 2670 (Sheen et al. 2017, ApJL, 840, L7). Our MUSE IFU spectra revealed a rotating gas disk in the center of the galaxy and long ionised gas tails emanating from the disk. Its one-sided tails and a tadpole-like morphology of star-forming blobs around the galaxy suggested that the galaxy is experiencing strong ram-pressure stripping in the cluster environment. Stellar kinematics with stellar absorption lines in the MUSE spectra demonstrated that the galaxy is an elliptical galaxy without any hint of a stellar disk. Then, the primary question would be the origin of the rich gas component in the elliptical galaxy. A plausible scenario is a wet merger with a gas-rich companion. In order to investigate star formation history of the system (the galaxy and star-forming blobs), we derived star-formation rate and metallicity from the MUSE spectra. Photometric UV-Optica-IR SED fitting was also performed using GALEX, SDSS, 2MASS and WISE data, to estimate dust and gas masses in the system. For a better understanding of star formation history and environmental effect of this galaxy, FIR/sub-mm follow-up observations are proposed.

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Chemical Properties of Star-Forming Dwarf Galaxies in Different Environments

  • Chung, Jiwon;Rey, Soo-Chang;Sung, Eon-Chang;Lee, Woong;Kim, Suk;Lee, Yongdae
    • The Bulletin of The Korean Astronomical Society
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    • v.42 no.1
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    • pp.49.2-49.2
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    • 2017
  • Star forming dwarf galaxies in various environments are attractive objects for investigating the environmental effects on chemical evolution of dwarf galaxies. Using SDSS DR7 spectroscopic data and GALEX ultraviolet (UV) imaging data, we study the chemical properties of star forming dwarf galaxies in various environments of the Virgo cluster, Ursa Major group, and field. We derived gas-phase abundance, galaxy mass, and UV specific star formation rate (sSFR) of subsample, early-type (ETD) and late-type star forming dwarf (LTD) galaxies, which are divided by visually classified galaxy morphology. We found no O/H enhancement of LTDs in cluster and group environments compared to the field, implying no environmental dependence of the mass-metallicity relation for LTDs. LTDs in the Virgo cluster and Ursa Major group have similar sSFR at a given galaxy mass, but they exhibit systematically lower sSFR than those in isolated field environment. We suggest that LTDs in the Virgo cluster are an infalling population that was recently accreted from the outside of the cluster. We found that ETDs in the Virgo cluster and Ursa Major group exhibit enhanced O/H compared to those in the field. However, no distinct difference of N/O of galaxies between different environments. The chemically evolved ETDs in the Virgo cluster and Ursa Major group also show similar mass-sSFR relation, but systematically lower sSFR at a fixed galaxy mass compared to the field counterparts. We suggest that ETDs in the Virgo cluster and Ursa Major group have evolved under the similar local environments. We also discuss the evolutionary path of ETDs and LTDs with respect to the environmental effects of ram pressure stripping and galaxy interaction/merging.

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TRAO Key Science Program: mapping Turbulent properties In star-forming MolEcular clouds down to the Sonic scale (TIMES)

  • Yun, Hyeong-Sik;Lee, Jeong-Eun;Choi, Yunhee;Lee, Seokho;Baek, Giseon;Lee, Yong-Hee;Choi, Minho;Kang, Hyunwoo;Tatematsu, Ken'ichi;Gaches, Brandt A.L.;Heyer, Mark H.;Evans, Neal J. II;Offner, Stella S.R.;Yang, Yao-Lun
    • The Bulletin of The Korean Astronomical Society
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    • v.43 no.1
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    • pp.66.1-66.1
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    • 2018
  • Turbulence is a phenomenon which largely determines the density and velocity fields in molecular clouds. Turbulence can produce density fluctuation which triggers a gravitational collapse, and it can also produce a non-thermal pressure against gravity. Therefore, turbulence controls the mode and tempo of star formation. However, despite many years of study, the properties of turbulence remain poorly understood. As part of the Taeduk Radio Astronomy Observatory (TRAO) Key Science Program (KSP), "apping Turbulent properties In star-forming MolEcular clouds down to the Sonic scale (TIMES; PI: Jeong-Eun Lee)", we have mapped two star-forming clouds, the Orion A and the ${\rho}$ Ophiuchus molecular clouds, in 3 sets of lines (13CO 1-0/C18O 1-0, HCN 1-0/HCO+ 1-0, and CS 2-1/N2H+ 1-0) using the TRAO 14-m telescope. We aim to map entire clouds with a high-velocity resolution (~0.05 km/s) to compare turbulent properties between two different star-forming environments. We will present the preliminary results using a statistical method, Principal Component Analysis (PCA), that is a useful tool to represent turbulent power spectrum.

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Investigation of entanglement dynamics of flexible polymer chains via comparison of dielectric and viscoelastic properties: a review of recent findings

  • Watanabe, H.
    • Korea-Australia Rheology Journal
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    • v.13 no.4
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    • pp.205-217
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    • 2001
  • This review article summarizes results of recent viscoelastic and dielectric studies for entangled cis-polyisoprene (PI) chains. The PI chains have the so-called type-A dipoles parallel along the chain backbone, and their slow viscoelastic and dielectric relaxation processes reflect the same global chain motion. However, this motion is differently averaged in the viscoelastic and dielectric properties, the former representing the isochronal orientational anisotropy of individual entanglement segments while the latter detecting the orientational correlation of the segments at two separate times (0 and t). On the basis of this difference, the viscoelastic and dielectric data of the entangled PI chains were compared to elucidate detailed features of the chain dynamics. Specifically, the molecular picture of dynamic tube dilation (DTD) incorporated in recent models was tested for linear and star PI chain. The comparison revealed that the DTD picture was valid for linear PI chains but failed for the star PI chains in the dominant part of the terminal relaxation. The failure for the star chains was related to the pre-requisite for the DTD process, rapid equilibration of successive entanglement segments through their constraint release (CR) motion: For the star chains, the dilated tube diameter expected in the terminal regime was considerably large because of a broad distribution of motional modes of the chains, so that the CR-equilibration required for DTD could not occur in time. The terminal relaxation of the star chain appeared to occur through the CR process before the expected DTD process was completed. The situation was different for the linear chain exhibiting narrowly distributed motional modes. The dilated tube expected for the linear chain was rather thin and the required CR-equilibration occurred in time, resulting in the success of the DTD picture. These detailed features of the chain dynamics was revealed only when the viscoelastic and dielectric properties were compared, demonstrating the importance of this comparison.

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A NEAR-INFRARED STUDY OF THE HIGHLY-OBSCURED ACTIVE STAR-FORMING REGION W51B

  • Kim, Hyo-Sun;Nakajima, Yasushi;Sung, Hwan-Kyung;Moon, Dae-Sik;Koo, Bon-Chul
    • Journal of The Korean Astronomical Society
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    • v.40 no.1
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    • pp.17-28
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    • 2007
  • We present wide-field $JHK_s$-band photometric observations of the three compact H II regions G48.9-0.3, G49.0-0.3, and G49.2-0.3 in the active star-forming region W51B. The star clusters inside the three compact H II regions show the excess number of stars in the $J-K_s$ histograms compared with reference fields. While the mean color excess ratio $(E_{J-H}/E_{H-K_s})$ of the three compact H II regions are similar to ${\sim}2.07$, the visual extinctions toward them are somewhat different: ${\sim}17$ mag for G48.9-0.3 and G49.0-0.3; ${\sim}23$ mag for G49.2-0.3. Based on their sizes and brightnesses, we suggest that the age of each compact H II region is ${\leq}2\;Myr$. The inferred total stellar mass, ${\sim}1.4{\times}10^4M_{\odot}$, of W51B makes it one of the most active star forming regions in the Galaxy with the star formation efficiency of ${\sim}10%$.

The effect of K-POP characteristics on the liking of Korean Wave content, the intention of listening and the purchase intention of Korean products: Targeting Chinese consumers (K-POP 특성이 한류콘텐츠 호감도와 청취의도 및 한국제품 구매의사에 미치는 영향: 중국소비자를 대상으로)

  • Yu, Seung Yeob
    • Journal of Digital Convergence
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    • v.15 no.9
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    • pp.201-210
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    • 2017
  • This study investigated the effect of K-POP characteristics on Korean consumers' liking, intention of listening and purchase intention of Korean products. For this purpose, K-POP characteristics were classified into musical characteristics and star characteristics. The results of the study are as follows. First, both musical characteristics and star characteristics of K-POP characteristics had a significant effect on favorability of Korean Wave content. Second, both musical characteristics and star characteristics of K-POP have a significant effect on K-POP listening intention. Third, both musical characteristics and star characteristics of K-POP characteristics had a significant effect on the purchase intention of Korean products through Korean Wave content. However, the relative influence of star characteristics is higher than K-POP characteristics. The results of this study will be useful data for promoting Korean pop among Chinese consumers.

The Type and Characteristics of Korean Sport Star' TV Commercial by Period (시대별 한국 스포츠 스타 TV광고의 형태와 특성)

  • Yi, Eun-Surk
    • Journal of Digital Convergence
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    • v.15 no.9
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    • pp.543-550
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    • 2017
  • The purpose of this study is to investigate the change of the type and characteristics of Korean sports star TV commercials and to deeply investigate the relationship with social contexts and backgrounds. In order to solve the purpose of this study, This study collected data of 38,517 TV advertisements from 1970 to 2009, and analyzed data of 146 media contents. The results obtained are as follows. First, Korean sports star TV commercials showed a steady increase with the economic growth and media development of Korea, and the percentage of total TV advertisements was low. Second, sports star TV advertising plays a role of expanding the sports industry, but it shows that the efficiency of relationship persistence decreases without social situation and public recognition.

DEVELOPMENT OF PRECISION ATTITUDE DETERMINATION SYSTEM FOR KOMPSAT-2

  • Yoon Jae-Cheol;Shin Dongseok;Lee Hungu;Lee Young-Ran;Lee Hyunjae;Bang Hyo-Choong;Cheon Yee-Jin;Shin Jae-Min;Moon Hong-Youl;Lee Sang-Ryool;Jeun Gab-Ho
    • Bulletin of the Korean Space Science Society
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    • 2004.10b
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    • pp.296-299
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    • 2004
  • KARI precision attitude determination system has been developed for high accurate geo-coding of KOMPSAT-2 image. Sensor data from two star trackers and a IRU are used as measurement and dynamic data. Sensor data from star tracker are composed of QUEST and unit vector filter. Filter algorithms consists of extended Kalman filter, unscented Kalman filter, and least square batch filter. The type of sensor data and filter algorithm can be chosen by user options. Estimated parameters are Euler angle from 12000 frame to optical bench frame, gyro drift rate bias, gyro scale factor, misalignment angle of star tracker coordinate frame with respect to optical bench frame, and misalignment angle of gyro coordinate frame with respect to optical bench frame. In particular, ground control point data can be applied for estimating misalignment angle of star tracker coordinate frame. Through the simulation, KPADS is able to satisfy the KOMPSAT-2 mission requirement in which geo-location accuracy of image is 80 m (CE90) without ground control point.

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