• Journal of The Korean Astronomical Society
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• v.32 no.2
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• pp.119-126
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• 1999

The standard stellar models for $\alpha$ Cen A and B have been constructed without resorting to the arbitrary constraint of the Solar mixing length ratio. Assuming that the chemical compositions and the ages of the two stars are the same, series of models have been constructed. Using the observational constraints, [Z/X], we were able to constrain the number of the 'possible' models. We find that utilizing the observational constraints of [Z/X] the best models for $\alpha$ Cen system are with the initial Z = 0.03, X = 0.66$\~$0.67. In particular, the primary and the secondary stars may have the same mixing length ratio 1.6$\~$1.7, which is the same as that of the calibrated Solar model. And, the age of the system is about 5.4 Gyr. Finally, the large spacing of the p-modes is predicted to be 104 $\pm$ 4$\mu$Hz for $\alpha$ Cen A.

• Journal of The Korean Astronomical Society
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• v.48 no.2
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• pp.93-104
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• 2015

WFIRST microlensing observations will return high-precision parallaxes, σ(π) . 0.3 µas, for the roughly 1 million stars with H < 14 in its 2.8 deg² field toward the Galactic bulge. Combined with its 40,000 epochs of high precision photometry (∼ 0.7 mmag at H_vega = 14 and ∼ 0.1 mmag at H = 8), this will yield a wealth of asteroseismic data of giant stars, primarily in the Galactic bulge but includindvvvvvg a substantial fraction of disk stars at all Galactocentric radii interior to the Sun. For brighter stars, the astrometric data will yield an external check on the radii derived from the two asteroseismic parameters, the large-frequency separation <∆ν_nl> and the frequency of maximum oscillation power ν_max, while for the fainter ones, it will enable a mass measurement from the single measurable asteroseismic parameter ν_max. Simulations based on Kepler data indicate that WFIRST will be capable of detecting oscillations in stars from slightly less luminous than the red clump to the tip of the red giant branch, yielding roughly 1 million detections.

• Publications of The Korean Astronomical Society
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• v.15 no.spc1
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• pp.15-30
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• 2000

A large scatter of the chemical abundances among globular cluster red giants has been observed. Especially the chemical elements C, N, O, Na, Mg, and Al vary form star to star within globular clusters. Except for $\omega$ Cen and M22, most globular clusters could be considered to be monometallic of their iron peak elements within error ranges. The variations in light elements among globuar cluster giants appear much more pronounced than in field halo giants of comparable Fe-peak metallicity. It has been found that in general the nitrogen abundance is anticorrelated with both carbon and oxygen, while it is correlated with Na and AI. These intracluster abundance inhomogeneities can be interpreted either by mixing of nucleosythesized material from the deep stellar interior during the red giant branch phase of evolution or by inhomogeneities of primordially processed material, from which the stars were formed. The simple way of distingushing between two senarios is to obtain the element abundances of main-sequence stars in globular clusters, which are too faint for high resolution spectroscopic studies until now. Both 'evolutionary' and 'primodial' origins are accepted for explanations of abundance variations among red giants and CN-CH anticorrelations among main-sequence stars in globular clusters. This paper reviews chemical abundances of light elements among globular cluster giants, with brief reviews of cannonical stellar evolution of low mass stars after main-sequence and deep mixing for abundance variations of cluster giants, and a possible connection between deep mixing and second parameter.

• 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.

• Journal of the Korean Society of Clothing and Textiles
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• v.24 no.5
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• pp.675-685
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• 2000

The fashion leadership, use of fashion information, and apparel shopping behavior of middle-and high-school male students were examined. The interrelationship of the three variables was also analysed. Subjects were 600 male students in Kang-Bouk and kang-Nam. Major findings indicated that fashion consciousness and confidence were the significant factors in fashion innovativeness and opinion leadership. And the outfit of celebrities(popular signer and film stars) was the most influential factors in the fashion leadership. Among commercial informations, the display and interior was more effective than advertisings. The higher the innovativeness, the more subjects wanted to accompany friends rather than parents and also the more time was spent in their shopping.

• Journal of the Korean Society of Costume
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• v.52 no.4
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• pp.75-85
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• 2002

The degree of involvement was known to shape the types of decision- process behavior of consumers. The types of information search would be influenced according to the degree of involvement. The purpose of this study was to find out the fashion information sources used in clothing purchase, and to clarify the interrelationship of clothing involvement and information sources. The middle and high school girls in Seoul were the subjects of the study. The information sources were classified into three types; marketer-oriented, internal and personal sources. Fashion informations spreaded by mass media were the most diversely used by teens. Among fashion information sources, ‘my own thoughts and experiences’ was counted as the most important one. And ‘interior and display of the shop’ was more important than the other marketer-oriented informations. Clothing involvement in the aspect of pleasure/symbol showed meaningful correlation with the information of ‘street fashion’, but in the aspect of fashion consciousness, ‘fashion of movie stars and celebrities’was the most significant information source. It seemed that ‘fashion articles in the magazines’ was used to reduce perceived risk in clothing purchase.

• Journal of The Korean Astronomical Society
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• v.47 no.6
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• pp.259-277
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• 2014

G192.8-1.1 has been known as one of the faintest supernova remnants (SNRs) in the Galax until the radio continuum of G192.8-1.1 is proved to be thermal by Gao et al. (2011). Yet, the nature of G192.8-1.1 has not been fully investigated. Here, we report the possible discovery of faint non-thermal radio continuum components with a spectral index ${\alpha}{\sim}0.56(S_{\nu}{\propto}{\nu}^{-{\alpha}})$ around G192.8-1.1, while of the radio continuum emission is thermal. Also, our Arecibo $H_I$ data reveal an $H_I$ shell, expanding with an expansion velocity of $20-60km\;s^{-1}$, that has an excellent morphological correlation with the radio continuum emission. The estimated physical parameters of the $H_I$ shell and the possible association of non-thermal radio continuum emission with it suggest G192.8-1.1 to be an~0.3 Myr-old SNR. However, the presence of thermal radio continuum implies the presence of early-type stars in the same region. One possibility is that a massive star is ionizing the interior of an old SNR. If it is the case, the electron distribution assumed by the centrally-peaked surface brightness of thermal emission implies that G192.8-1.1 is a "thermal-composite" SNR, rather than a typical shell-type SNR, where the central hot gas that used to be bright in X-rays has cooled down. Therefore, we propose that G192.8-1.1 is an old evolved thermal-composite SNR showing recurring emission in the radio continuum due to a nearby massive star. The infrared image supports that the $H_I$ shell of G192.8-1.1 is currently encountering a nearby star forming region that possibly contains an early type star(s).

• Korean Institute of Interior Design Journal
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• v.26 no.6
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• pp.116-125
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• 2017

The study is aimed to analyze cases of hotel room designs based on the 'Art Quotient'. It is focused on design elements of livability, analyzing the space design in terms of biophilic design and experiential marketing. This paper proposes a direction for hotel design based on the analysis result. The scope of the study includes the cases of 17 hotels in the area of Seoul achieving five stars in Korea. This paper presents an analysis whether the room space of hotels provide a user-oriented life experience from the perspective of biophilic design and experiential marketing. In this study, we focused on the concept of 'refuge', one of the biophilic design elements that express the value of life sense, and the element of 'sense', one of the strategic experiential modules of experiential marketing. After analyzing the hotel case studies, the space was evaluated using five factors of art quotient as a design method to provide a life experience in the hotel room. Analysis of the design space from the viewpoint of refuge, rather than architectural elements, proved that decorative elements appeared most commonly in all hotel rooms. Further, through an analysis based on the measures of 'sense', an experiential element, visual elements were mostly enforced in among the elements of the five senses. In other words, when designing a hotel room space, visual elements such as color, pattern, furniture, lighting and style are mainly utilized. Examining the analysis of the design elements from the point of view of the art quotient, the rooms of all the hotel's suite types include elements of 'communication'. Most of the hotel rooms focused on stimulating the aesthetic sensibility of customers. This resulted in the elements of 'immersion' showing poor results. In conclusion, it is necessary to provide the five senses of the arts index in a balanced manner to provide a life experience through the five senses.

• Korean Institute of Interior Design Journal
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• no.12
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• pp.57-66
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• 1997

This study was carried out to find out some similarities and differences of the ornamental technique and motifs in folk furniture between Denmark and Korea which had quite different background of development of folk furniture as one of a cross-cultural study. Furniture made and used in the 18th and 19th century was investigated in order to eliminate the influence of internationalism in the design area in the 20th century. This study was fulfilled by many study trips all over the districts in Denmark to identify Danish folk furniture as well as literature study. Study trips to folk museums. Insa-dong, Janghanpyung furniture market were done for Korean folk furniture. Characteristics of ornament in Danish folk furniture were as followings; Main materials of the Danish folk furniture were conifers, especially pine tree, as pine was very common and easy to get from their surroundings. The most popular and unique types of decoration in Danish folk furniture was painting. Colors used in painted furniture were very bright and vivid. This might be a reaction to the long and dark winter of Scandinavian countries. Motifs used in Danish folk furniture had been chosen to reflect their surroundings. Flowers, six-angular stars, animals, human figures and Biblical motifs were popular sources of decoration for Danish folk furniture. Characteristics of Korean folk furniture were as followings; Main materials of Korean folk furniture were broad-leaved trees as well as conifers, because of their beautiful wood grain. The Korean ways of decoration were different from Danish ones. The method of painting with bright from Danish ones. The method of painting with bright colors was hardly ever used in Korea, except only in lacquering. The most popular decoration method for Korean folk furniture was revealing the natural wood grain with transparent vegetable oil finish, instead of painting. Metal ornament was unique to Korean folk furniture. therefore a lot of metal ornaments were attached on the furniture. Motifs used in Korean folk furniture were more like symbolic than Danish ones. Korean people tried to express their longings and norms through the motifs, such as longevity, prosperity, good luck, and many sons, etc. Therefore, it was natural for Korean motifs to have special symbolic meanings.

• The Bulletin of The Korean Astronomical Society
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• v.42 no.1
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• pp.54.1-54.1
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• 2017

The UKIRT Wide-field Infrared survey for Fe+(UWIFE) is an unbiased survey of the first Galactic quadrant, with narrow-band filter centered on $1.644{\mu}m$. This survey covers $7^{\circ}$ < l < $62^{\circ}$ and |b| < $1.5^{\circ}$, where active interaction of stars and interstellar medium is expected. With median seeing of 0.8 arcsec, 5 - sigma detection limit of 18.7 mag and surface brightness limit of $8.1{\times}10^{-20}W\;m^{-2}arcsec^{-2}$, this survey gives an opportunity to statistically study Galactic [Fe II] - emitting sources for the first time. In order to identify Ionized Fe Objects (IFOs) in survey area systematically, we conducted visual inspection and automatic detection simultaneously. Total of ~300 extended IFOs are identified, most of them are found out to be part of supernova remnants (SNRs), young stellar objects, HII regions and planetary nebulae. The majority of IFOs are new discoveries which reveal shocked structures in high-extinction region. Spatial distribution of IFOs suggest that they trace Galactic structure. As a part of spectroscopic follow-up, we observed SNR candidate IFO J183740.829-061452.41 with IGRINS (Immersion Grating Infrared Spectrograph, Yuk+2010), mounted on 2.7m Harlan Smith telescope. This unknown arc-like, 6'-long IFO is coincident with inner part of radio continuum loop G25.8+0.2, which has been known as HII region. However, interior of this radio shell is filled with diffuse soft X-ray emission, and possible association of hard X-ray pulsar / pulsar wind nebula makes the nature of the IFO unclear. The H and K-band 2D spectrum shows shock-ionized [Fe II] filaments, which is apart from photoionized HII filaments. In this presentation we present basic statistics of newly identified IFOs, as well as the follow-up study of IFO J183740.829-061452.41.