• The Bulletin of The Korean Astronomical Society
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• v.42 no.1
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• pp.44.2-44.2
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• 2017

Multiple stellar systems composed of triple, double+double or double+triple, etc. are very rare and interesting objects for understanding the star formation and dynamical evolution. However, only six systems have been found to be a doubly eclipsing quadruple, which consists of two eclipsing binaries, and four systems to be a triply eclipsing hierarchical triple. Recently, the 15 doubly eclipsing multiple candidates located in the Large Magellanic Cloud (LMC) have been reported by the OGLE project. In order to examine whether these candidates are real multiple systems with eclipsing features, we performed a high-cadence time-series photometry for the LMC using the KMTNet (Korea Microlensing Telescope Network) 1.6 m telescopes in three site (CTIO, SAAO, and SSO) during 2016-2017. The KMTNet data will help reveal the photometric properties of the multiple-star candidates. In this paper, we present the VI light curves and their preliminarily analyses for 12 of the 15 eclipsing systems in the LMC, based on our KMTNet observations and the OGLE-III survey data from 2001-2009.

• The Bulletin of The Korean Astronomical Society
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• v.42 no.1
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• pp.46.1-46.1
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• 2017

Class I methanol masers are found to be good tracers of the interaction between outflows from massive young stellar objects with their surrounding media. Although polarization observations of Class II methanol masers have been able to provide information about magnetic fi elds close to the central (proto)stars, polarization observations of Class I methanol masers are rare, especially at 44 and 95GHz. We present the results of linear polarization observations of 39 Class I methanol maser sources at 44 and 95GHz. These two lines are observed simultaneously with one of the 21m Korean VLBI Network telescopes in single-dish mode. Approximately 60% of the observed sources have fractional polarizations of a few percent in at least one transition. This is the fi rst reported detection of linear polarization of the 44GHz methanol maser. We also observed 7 targets with the KVN in VLBI mode. We will present its preliminary results, too.

• The Bulletin of The Korean Astronomical Society
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• v.43 no.1
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• pp.40.4-41
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• 2018

We introduce a coordinate catalog for photometry of the KMTNet Galactic bulge observation program and how to find the microlensing event candidates in the photometry result. Basically, the KMTNet bulge program is monitoring a total of 27 target fields (108 deg2) with four different cadences of 0.5, 1.0, 2.5, and 5.0 hours. In order to measure the stellar flux of each target, we made a 'observation coordinate catalog' by using the 'OGLE-III catalog' and 'DoPhot package'. The catalog contains approximately 0.3 billion stars in the bulge fields. We also search for a microlensing event candidates by means of the 'Event Finder algorithm' which calculates the restricted single-lens fitting (t0, teff, u0; u0 = 0 or 1) model. As a result, we found more than 2,000 microlensing event candidates per each year including about 700 events from the other survey groups such as OGLE and MOA. In this year, we will improve our current pipeline system, e.g. upgrading the catalog and applying real-time photometry.

• The Bulletin of The Korean Astronomical Society
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• v.43 no.1
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• pp.70.1-70.1
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• 2018

The DEEP-South photometric census of small Solar System bodies is producing massive time-series data of variable, transient or moving objects as a by-product. To fully investigate unexplored variable phenomena, we present an application of multi-aperture photometry and FastBit indexing techniques to a portion of the DEEP-South year-one data. Our new pipeline is designed to do automated point source detection, robust high-precision photometry and calibration of non-crowded fields overlapped with area previously surveyed. We also adopt an efficient data indexing algorithm for faster access to the DEEP-South database. In this paper, we show some application examples of catalog-based variability searches to find new variable stars and to recover targeted asteroids. We discovered 21 new periodic variables including two eclipsing binary systems and one white dwarf/M dwarf pair candidate. We also successfully recovered astrometry and photometry of two near-earth asteroids, 2006 DZ169 and 1996 SK, along with the updated properties of their rotational signals (e.g., period and amplitude).

• The Bulletin of The Korean Astronomical Society
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• v.43 no.1
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• pp.60.2-60.2
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• 2018

We present the near infrared JHK photometric properties and the spatial distribution of red supergiants(RSGs) of NGC 3623, NGC 3627 and NGC 3628 in the Leo Triplet system using the data obtained with 3.8m UKIRT(United Kingdom Infra-Red Telescope) at Hawaii. We checked interaction between the three galaxies by making a spatial density map of RSGs. From (J-K,K)0 Color-Magnitude Diagram which include resolved stars in three galaxy and control field with PARSEC isochrone, we figured out the RSG candidates of the Leo triplet are at 0.9<(J-K)0<1.2, mK<17.5 and separated them from background and foreground sources. Using gaussian kernel density estimation, we drew spatial density map of RSGs in the Leo triplet with an assumption that all RSGs are an identical population. The density map shows extended features of NGC 3628 to NGC 3627 along the declination direction. The asymmetries between NGC 3627 and NGC 3628 might be evidence for that the distribution of actual star components(RSGs) follows the neutral hydrogen distribution and also for interaction between two galaxies. And the extended features along the right ascension direction might be a supporting evidence for the existence of a TDG(Tidal Dwarf Galaxy). In case of NGC 3623, we could not see any sign of interaction in density map.

• The Bulletin of The Korean Astronomical Society
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• v.43 no.1
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• pp.57.1-57.1
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• 2018

Reionisation in the early Universe is likely driven by dwarf galaxies. Using cosmological RHD simulations, we study star formation and the escape of Lyman continuum (LyC) photons from mini-haloes with Mhalo<108Msun. We find that feedback reduces star formation very efficiently in mini-haloes, resulting in the stellar mass consistent with the empirical stellar mass-to-halo mass relation derived in the local Universe. Because star formation is stochastic and dominated by a few gas clumps, the escape fraction in mini-haloes is generally determined by photo-ionization, rather than supernova explosions. We find that the photon number-weighted mean escape fraction in mini-haloes is higher (20-40%) than that in atomic-cooling haloes. Despite their high escape fractions, LyC photons from mini-haloes are of minor importance for reionization due to inefficient star formation. We confirm previous claims that stars in atomic-cooling haloes with masses $10^8M_{sun}$$10^{11}M_{sun}$ are likely to be the most important source of reionization.

• Journal of architectural history
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• v.19 no.4
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• pp.21-34
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• 2010

Through investigating the effects that result from the form and preference of Ahnsan (案山) and Jusan(主山) symbolizing ground in the cases of 21 of the Korean Academics for classical learning which called Seowon(書院) located in South Korea of the whole 47, to layout the Korean Academics for classical learning, what factor Sarim(士林) preferred to and how they analyzed the form of circumjacent mountains by Fengshui. While the Jusan has intrinsic attribute due to connecting with the place, Hyuljang(穴場), the Ahnsan has public and extrovert. It can be explained that the Sarim who established the Korean Academics for classical learning had their internal hope and external justification. To put it concretely, because of their necessity of concentrating on their study within nature and their situation as hermits apart from government through long time, they made the Korean Academics for classical learning stable and satisfactory. Therefore, they had to choose Moogocksung(武曲星) as a Jusan. And their study was essential method to take their justification. And It was attractive for them to be a public officer by their study. So they preferred to Moonpilbong(文筆峯) symbolizing their achievements on their study. So the layout of the Korean Academics for classical learning tells us that the Sarim sought internal stability and external scholarship.

• Journal of Korea Game Society
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• v.14 no.6
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• pp.69-78
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• 2014

The purpose of this paper is to analyze a developing process of 3D STEAM based G learning contents. STEAM means Science, Technology, Engineering, Art, Mathematics. It is focused on to raise students interest on science and technology through integrating the subjects together. Also it's purpose is to raise students understanding capabilities on technology convergence and problem solving. Therefore, this paper focused on the analysis of the development of 3D STEAM based G learning contents. Science topic, 'solar system and stars' was decided as a G learning based contents. Students showed higher immersion and motivation on the contents.

• The Research Journal of the Costume Culture
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• v.12 no.5
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• pp.880-896
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• 2004

Trompe l'Oeil technique strategically conceived with a view to effectively realize creative ideas among the expression techniques of fine arts style has provided the driving force in development of fine arts and has continuously influenced development of the modem fashion pursuing unique individuality. The study is focused first on finding out how Trompe l'Oeil technique originated in connection with researching the fashion of Trompe l'Oeil and on analysing the technique of expression. The author referred to fashion magazines for designing ideas of Trompe l'Oeil represented in modem fashion in practical applications used by designers in Paris, Italy, London and New York during the 10 year period(1990-1999). The collections of data were analyzed as following: Effectiveness depending on the method of Trompe l'Oeil I. Effectiveness of Layering: when two clothing are over lapped or coordinated with one another in color or style. 2. Effectiveness of Detailing: when pictures, stitch, tape, cutting, quilting and etc are used to create collar, pocket, yoke, zipper, string, shadow and etc. 3. Effectiveness of Accessories: when the image of necklace, belt, tie, tassel, badges and stars are represented by illustration or embroidery on clothing to substitute the actual existence. 4. Effectiveness of Nudity: when human body is realistically drawn and printed on clothing.

• Journal of the Korean Society of Costume
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• v.54 no.6
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• pp.91-100
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• 2004

The purpose of this study is to evaluate the influence of T-shirt as a movie costume on the modem mass fashion. The way of study is to analyze the changes of men's image with T-shirt as Hollywood actors costume in 50's and 60's. The costumes create the characters with meanings and symbols moreover they lead fashion as well as promoting artistic value of films. At the end of the 19th century, this shirt learnt the ropes in the U.S. Navy well before it won the hearts of sportsmen and workers alike, with its twin virtues of comforts and hygiene. When American soldiers returned home after World War II showing their T-shirts in the sweltering heat of the Tropics, their shirts were as heroic as they were. Furthermore the new stars of Hollywood, going by such names as Marlon Brando and James Dean, gave the T-shirt its rebel cachet and showed the whole world. Be it tom open on Marlon Brando's torso in Elia Kazan's 'A Streetcar Named Desire', or peeping out dazzlingly white from under James Dean's red jacket in 'Rebel Without a Cause', the T-shirt flaunted its sexuality and emanated the sweet smell or revolt. It would be the banner of rebellion for a whole generation. The T-shirt had finally found its way into the history of fashion and was there to stay.d was there to stay.