1,572 research outputs found

    Proto-type installation of a double-station system for the optical-video-detection and orbital characterisation of a meteor/fireball in South Korea

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    We give a detailed description of the installation and operation of a double-station meteor detection system which formed part of a research & education project between Korea Astronomy Space Science Institute and Daejeon Science Highschool. A total of six light-sensitive CCD cameras were installed with three cameras at SOAO and three cameras at BOAO observatory. A double-station observation of a meteor event enables the determination of the three-dimensional orbit in space. This project was initiated in response to the Jinju fireball event in March 2014. The cameras were installed in October/November 2014. The two stations are identical in hardware as well as software. Each station employes sensitive Watec-902H2 cameras in combination with relatively fast f/1.2 lenses. Various fields of views were used for measuring differences in detection rates of meteor events. We employed the SonotaCo UFO software suite for meteor detection and their subsequent analysis. The system setup as well as installation/operation experience is described and first results are presented. We also give a brief overview of historic as well as recent meteor (fall) detections in South Korea. For more information please consult http://meteor.kasi.re.kr .Comment: Technical/instrumentation description of a professional meteor detection system, 23 pages, 20 figures (color/monochrome), 5 tables, submitted to the Journal of Korean Astronomical Society (JKAS, http://jkas.kas.org/, http://jkas.kas.org/history.html

    Applications of pre-open sets

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    [EN] Using the concept of pre-open set, we introduce and study topological properties of pre-limit points, pre-derived sets, preinterior and pre-closure of a set, pre-interior points, pre-border, prefrontier and pre-exterior. The relations between pre-derived set (resp. pre-limit point, pre-interior (point), pre-border, pre-frontier, and preexterior) and α-derived set (resp. α-limit point, α-interior (point), α-border, α-frontier, and α-exterior) are investigatedJun, YB.; Jeong, SW.; Lee, HJ.; Lee, JW. (2008). Applications of pre-open sets. Applied General Topology. 9(2):213-228. https://doi.org/10.4995/agt.2008.18022132289

    Pulsed Laser Deposition of Rocksalt Magnetic Binary Oxides

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    Here we systematically explore the use of pulsed laser deposition technique (PLD) to grow three basic oxides that have rocksalt structure but different chemical stability in the ambient atmosphere: NiO (stable), MnO (metastable) and EuO (unstable). By tuning laser fluence, an epitaxial single-phase nickel oxide thin-film growth can be achieved in a wide range of temperatures from 10 to 750 {\deg}C. At the lowest growth temperature, the out-of-plane strain raises to 1.5%, which is five times bigger than that in a NiO film grown at 750 {\deg}C. MnO thin films that had long-range ordered were successfully deposited on the MgO substrates after appropriate tuning of deposition parameters. The growth of MnO phase was strongly influenced by substrate temperature and laser fluence. EuO films with satisfactory quality were deposited by PLD after oxygen availability had been minimized. Synthesis of EuO thin films at rather low growth temperature prevented thermally-driven lattice relaxation and allowed growth of strained films. Overall, PLD was a quick and reliable method to grow binary oxides with rocksalt structure in high quality that can satisfy requirements for applications and for basic research

    Erosion of Public Confidence in the Korean National Assembly

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    Using recent survey data, this paper aims to empirically investigate the state and source of Korean citizens' trust and confidence in the National Assembly. Roughly speaking, the National Assembly is trusted only by one out of ten citizens. Since the country's democratization, citizens' trust and confidence has been eroding. Presently, the National Assembly is the least trusted among the key public or private institutions. A cross-national comparison of liberal democracies in the world shows that only a few national legislatures are less trusted by their citizens than the Korean National Assembly. Furthermore, this study confirms the empirical validity of performance-based explanation about what factors generate citizens' trust and confidence in the National Assembly. At the aggregate level, an erosion of citizens' trustful attitude toward the legislature is matched by their decreased positive evaluation of the overall job performance by the legislature. At the individual level, a citizen's legislative trust and confidence depends mainly on his or her evaluation of the performance of the legislature itself, the executive interacting with it, or the democratic regime as a whole. Most Koreans pass an unfavorable judgment on the performance of the legislature, not because they think it is a simply idle institution but because politicians are seen to pursue partisan interests too frantically within the institution. Given its drained reservoir of citizens' favorable attitudes toward it, the present National Assembly, even with its heightened constitutional status and emerging policy activism, may not be likely to serve as a key agent for facilitating democratic consolidation on Korean soil

    Estimation of utility weights for human papilloma virus-related health states according to disease severity

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    Scenarios for the different HPV-related health states. (DOCX 38 kb
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