• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.42.1-42.1
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• 2016

We examined thousands of light curves of stars brighter than 18.0 mag in I band and less than mean magnitude error of 0.1 mag in V band from the OGLE-III eclipsing binary catalogue, and found 90 new binary systems exhibiting apsidal motion. In this study, the samples of apsidal motion stars in the SMC were increased by 250 percent than previously known. In order to determine the period of the apsidal motion for the binaries, we analysed in detail both light curves and eclipse timings using the MACHO and OGLE photometric database obtained for about 20 yrs. For the eclipse timing diagrams of the systems, new times of minimum light were derived from the full light curve combined at intervals of one yr from the survey data. The binaries presented in this paper have apsidal motion periods in the range of 12-918 yrs. An additional short-term oscillation was detected in five systems (OGLE-SMC-ECL-1634, 1947, 3035, 4946, and 5382), which most likely arise from the existence of a third body orbiting each eclipsing binary. All of the selected systems can be used for the statistical study of the interior structure of the stars in the SMC through their apsidal motions due to the homogeneous data and consistent analysis methods.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.1
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• pp.57.1-57.1
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• 2014

We present the preliminary results of CO outflow survey toward the 56 Very Low Luminosity Object (VeLLO) candidates at CO J=2-1 and J=3-2 transitions with two radio telescopes of the Caltech Submillimeter Observatory (CSO) and the Atacama Submillimeter Telescope Experiment (ASTE). The survey is aimed to understand the origin of the formation of low-mass stars or substellar objects. The VeLLO is a very faint (${\leq}0.1$ $L_{\odot}$) object deeply embedded in dense molecular clouds and believed to be a proto-brown dwarf which will be a brown dwarf or a faint protostar which has just formed with little mass accretion or which is in quiescent stage of episodic accretion. The candidates were searched for over all nearby ($d{\leq}450$ pc) Gould belt clouds and listed in a new catalogue of the VeLLO candidates by Kim et al. (2014 submitted). To diagnose present status and future fate of the VeLLOs, we conducted a systematic observation for the CO molecular outflows of the 56 VeLLOs to infer how accretion is being made around the VeLLOs. We found 17 VeLLO candidates either having a prominent wing in line profiles or showing bipolar intensity distribution of high velocity components. We will discuss the physical properties of these CO outflows and the identity of the VeLLO candidates.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.1
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• pp.33.2-33.2
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• 2014

Halo merger trees are essential backbones of semi-analytic models for galaxy formation and evolution. Recent studies have pointed out that extracting merger trees from numerical simulations of structure formation is non-trivial; different algorithm can give differing merger histories. Thus they should be carefully understood before being used as input for models of galaxy formation. As one of the projects proposed in the SUSSING MERGER TREES Workshop, we investigate the impact of different halo merger trees on a semi-analytic model. We find that the z = 0 global galaxy properties in our model show differences between trees when using a common parameter set, but that these differences are not very significant. However, the star formation history of the Universe and the properties of satellite galaxies can show marked differences between trees with different methods for constructing a tree. Calibrating the SAM for each tree individually to the empirical data can reduce the discrepancies between the z = 0 global galaxy properties, however this is at cost of increasing the differences in evolutionary histories of galaxies. Furthermore, the underlying physics implied can vary, resulting in key quantities such as the supernova feedback efficiency differing by factors of 2. Such a change alters the regimes where star formation is primarily suppressed by supernovae. Therefore, halo merger trees extracted from a common halo catalogue using different, but reliable, algorithms can result in a difference in the semi-analytic model, however, given the enormous uncertainties in galaxy formation physics, these are not necessarily significant.

• IE interfaces
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• v.12 no.2
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• pp.319-328
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• 1999

Today, offshore design field is concerned with system integration such as CIM(Computer Integrated Manufacturing), PDMS(Product Data Management System) and EDMS(Engineering Data Management System) in order to cope with the change of engineering specification as owner's requirements during construction stage of the project. This paper deals with the case study that describes about the efficient interface between material control system and 3D CAD system to support the design process in offshore industry using design rules involved the designer's knowledge. In this paper, we constructed an information system, called knowledge-based CAD interface systems, which is composed material code management system and 3D specification generator which automatically creates 3D catalogue anti specification by linking the material code, called short code, and the specification components of the 3D CAD system. As a result of the construction, it is possible to maintain consistency of the design process, and through reduction of the design processing time and improvement of the design process, competitiveness is improved.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.6
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• pp.1355-1362
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• 2007

In this paper, these setting can be useful in the microprocessor and sensor that designed to improve the efficiency of the photovoltaic system the photovoltaic position tracker device, and compared the normal photovoltaic system of fixed form with the photovoltaic system of solar position tracked form. Moreover, this is compared the catalogue of solar cell module and the simulation through a mathematics modelling with the solar cell's characteristic interpreting and that is composed an power conversion system with boost converter and voltage source inverter. This device can be used to the constant voltage control method for maximum power point tracking in boost converter control. Experiment Results is shown that using a SPWM(Sinusoidal Pulse Width Modulation) control method in inverter control.

• Proceedings of the KSRS Conference
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• 2002.10a
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• pp.803-803
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• 2002

Several environmental problems have occurred and extremely affected throughout the East Asia region. Satellite imageries and spatial information have been used in the applications of environmental and natural hazard management for years. Sharing these data and resources in the community is considered as one of the optimal solution. It would consequently bring cost saving to all participated countries and eventually be beneficial to mankind as a whole. Encouraged by these factors, ASEAN＋3 Satellite Image Archive for Environmental Study project was submitted by Thailand in the 3rd Senior Official Meeting between ASEAN, China, Japan and Korea (SEOM＋3 Meeting) and approved by the SEOM＋3. The main objectives of this project are to share satellite images, information related to natural resources and environmental issues, and to provide data information services to all ASEAN＋3 countries. The proposed system is basically embedded by distributed system. The network of data users, data providers, and the center will be established using the Internet. User can access, navigate, display, and even download some archived contents. Its service site can be generally categorized into two parts, which are environmental related data archive and the Integrated satellite image catalogue. The extension of web based GIS is also planned for future development so that GIS users can conduct some preliminary analysis directly on line. This presentation will indicate scope of work, system, working scenario, and work plan of the project.

• Journal of the Korean Society of Tobacco Science
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• v.23 no.1
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• pp.45-52
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• 2001

This study was carried out to evaluate the uncertainty in the analysis of total alkaloids and reducing sugar content in flue-cured tobacco. The sources of uncertainty associated with the analysis of total alkaloids and reducing sugar were the weighing of sample, the preparation of extracting solution, the addition of extracting solution into the sample, the preparation of standard solution, the precision of calibration curve for standard solution, the reproducibility of analysis, and the determination of water content in tobacco, etc. For the calculating uncertainties, Type A of uncertainty was evaluated by the statistical analysis of a series of observation, and Type B by the information based on supplier’s catalogue and/or certificated of calibration. It was shown that the main source of uncertainty was caused by the calibration curve of standard solution, the reproducibility of analysis, the volume measurement of 1$m\ell$, and the purity of nicotine reference material in the preparation of standard solution. The uncertainty in the addition of extracting solution, the sample weighing, the volume measurement of 100$m\ell$, and the determination of water content of tobacco contributed relatively little to the overall uncertainty. The expanded uncertainty of total alkaloids and reducing sugar in flue-cured tobacco at 95% level of confidence was $\pm$0.12% and $\pm$0.54%, respectively.

• Journal of Korean Classical Literature and Education
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• no.16
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• pp.207-235
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• 2008

This study investigated the formation of communication education which is based on the contemporary language education. Concretely I watched chronologically the proportion of culture element and behavior element, its change, and the contents of writing education. To achieve this, I took the ancient Greek language education as the main materials. The sophists are right if we think only the empirical world, because of the changeability of external world and the relativity of sense. On the other hand, Platon emphasized the ability of abstract thought which is inherent in the human inside. But today's education only emphasizes the 'expression' which came from the Platonic thought. So students fills their devastated inside with arbitrary idea in this history-forgotten social circumstance. It is very beneficial to make subject have some cultural studies and to enhance the sensation on the world through the writing of representation because these can be good to the growth of subject. It is our-not as educator but as a predecessor of human being-duty to set the catalogue of cultural studies of this age and to make students feel the fundamental harmony and the beauty of the world.

• The Bulletin of The Korean Astronomical Society
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• v.43 no.2
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• pp.32.3-32.3
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• 2018

We use the synthetic light-cone from the cosmological hydrodynamical simulation Horizon-AGN to produce a mock photometric galaxy catalogue on the redshift range 0

• The Bulletin of The Korean Astronomical Society
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• v.40 no.1
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• pp.43.1-43.1
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• 2015

We have discovered an unexplored population of galaxies featuring weak broad-line regions (BLRs) at z < 0.2 from detailed analysis of galaxy spectra in the Sloan Digital Sky Survey Data Release 7. These objects predominantly show a stellar continuum but also a broad $H{\alpha}$ emission line, indicating the presence of a low-luminosity active galactic nucleus (AGN) oriented so that we are viewing the central engine directly without significant obscuration. These accreting black holes have previously eluded detection due to their weak nature. The new BLR AGNs we found increased the number of known type 1 AGNs by 49%. Some of these new BLR AGNs were detected at the Chandra X-ray Observatory, and their X-ray properties confirm that they are indeed type 1 AGN. Based on our new and more complete catalogue of type 1 AGNs, we derived the type 1 fraction of AGNs as a function of [OIII] ${\lambda}5007$ emission luminosity and explored the possible dilution effect on the obscured AGN due to star-formation. The new type 1 AGN fraction shows much more complex behavior with respect to black hole mass and bolometric luminosity than suggested by the existing receding torus model. The type 1 AGN fraction is sensitive to both of these factors, and there seems to be a sweet spot (ridge) in the diagram of black hole mass and bolometric luminosity. Furthermore, we present a hint that the Eddington ratio plays a role in determining the opening angles. This work is submitted to ApJS.