• The Bulletin of The Korean Astronomical Society
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• v.41 no.2
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• pp.50.1-50.1
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• 2016

We have found cool homopause temperatures (Kim et al. 2016) of 180 - 250 K for the 8-micron North Polar Hot Spot (8NPHS) of Jupiter, which has been observed to be stationary at 180 deg (SysIII) longitude since the early 1980s. The 3-micron spectro-images of Jupiter that we analyzed were obtained with GNIRS, Gemini Near-Infrared Spectrograph at Gemini North on January 13, 2013(UT), and at $8{\mu}m$ on Feburary 6, 2013(UT) with TEXES, the Texas Echelon Cross Echelle Spectrograph at the NASA IRTF. The cool homopause was unexpected, and a possible implication of the relatively cool 8NPHS homopause compared with those of other auroral regions will be presented.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.283-283
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• 2010

Smart street light controller is a product with advance micro controller base for energy saving in conventional street lighting systems. Intelligent Street light controller are specially developed for automation and energy saving in conventional street light systems and lighting systems. It is so designed that it operates on sunrise & sun set timings according to longitude of particular location with facilitate to set month wise civil twilight timings to cope up with all seasons. Dimming (Power down) mode selection switch on/off at fixed times with relay or contactor. Night dimming, staggering and intelligent control reduces burn hours and increases the lifetime of lamps with about 30% and low annual operating cost type base are among the most inexpensive wireless technologies available. Low initial costs As PLC wireless, there is no need to establish cable connection.

• Journal of The Korean Astronomical Society
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• v.29 no.spc1
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• pp.129-131
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• 1996

The results on the deep low dispersion (1250 ${\AA}$/mm at $H_r, $30^{\circ}$ < I < $165^{\circ}$, $195^{\circ}$ < I < $210^{\circ}$, [b] < $5^{\circ}$; 7000${\AA}$/mm at A band, $50^{\circ}$ < I < $115^{\circ}$, b=$0^{\circ}$, b=${\pm}3.5^{\circ}$) spectral surveys of the MILKY WAY are presented. More than 2250 carbon stars were identified among them 1440 new ones. The C/M5+ ratio increases from 0.02 to 0.3 when longitude varies from $30^{\circ}$ to $210^{\circ}$. On the basis of A GENERAL CATALOG OF GALACTIC COOL CARBON STARS the surface distribution of carbon stars has been studied.

• Journal of The Korean Astronomical Society
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• v.29 no.spc1
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• pp.357-358
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• 1996

Reanalysis of the observations of Mars made at the Hida Observatory in 1975 with a new image processing method is reported. Red filter images taken in the period before vernal equinox (areocentric longitude of the sun Ls=$0^{\circ}$) revealed dark surface features at the northern high latitudes, while blue filter images taken at the same time showed the extensive polar hood. The latitude of the northernmost feature observed was about $67^{\circ}$N. An extensive north polar cap, which is predicted by most of the existing models and observed with Viking, did not exist in our reanalyzed images obtained at the Hida Observatory in 1975.

• Journal of The Korean Astronomical Society
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• v.48 no.1
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• pp.1-7
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• 2015

The orbital period changes of the W UMa eclipsing binary AU Ser are studied using the (O-C) method. We conclude that the period variation is due to mass transfer from the primary star to the secondary one at a very low and decreasing rate $dP/dt=-8.872{\times}10^{-8}$, superimposed on the sinusoidal variation due to a third body orbiting the binary with period $42.87{\pm}3.16$ years, orbital eccentricity $e=0.52{\pm}0.12$ and a longitude of periastron passage ${\omega}=133^{\circ}.7{\pm}15$. On studying the magnetic activity, we have concluded that the Applegate mechanism failed to describe the cycling variation of the (O-C) diagram of AU Ser.

• Journal of the Korean Society of Visualization
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• v.7 no.1
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• pp.21-28
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• 2009

The study of swirling flow is of technical and scientific interest because it has an internal recirculation field, and its tangential velocity is related to the curvature of streamline. The fluid flow for tubes and elbow of heat exchangers has been studied largely through experiments and numerical methods, but studies about swirling flow have been insufficient. Using the particle image velocimetry(PTV) method, this study found the time averaged velocity distribution with swirl and without swirl along longitude sections and the results appear to be physically reasonable. In addition, streamwise mean velocity distribution was compares with that of other. Furthermore, other experimental investigation was performed to study the characteristics of turbulent water flow in a horizontal circular tube by using liquid crystal. 2D PIV technique is employed for velocity measurement and liquid crystal is used for heat transfer experiments in water. Temperature visualization was made quantitatively by calibrating the colour of the liquid crystal versus temperature using various approaches.

• Journal of the Korean Solar Energy Society
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• v.30 no.5
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• pp.100-106
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• 2010

The purpose of this study is to predict the effective sky temperature on Osan City during the summer. The north latitude, east longitude of Osan City is $37^{\circ}06'$ and $127^{\circ}02'$. The altitude from the sea level is 48m. Empirical relations of the effective sky temperature suggested by Duffie and Beckman are compared on clear days. For the effective sky temperature prediction, data measured by the Korea Meteorological Administration is used as an input to the Bliss model. Both Hottel and Krondratyev model are used to calculate the water vapor emissivity. The results using Hottel's model match well with the empirical relation proposed by Bliss. The results show maximum, minimum, and average values depending on water vapor emissivity model. The maximum deviation is about 10K and is due to total emissivity model.

• The Bulletin of The Korean Astronomical Society
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• v.35 no.1
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• pp.66.2-66.2
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• 2010

We have studied the properties of interstellar turbulence as observed by Boston University-Five College Radio Astronomy Observatory (BU-FCRAO) Galactic Ring Survey (GRS). This observation uses 13CO J=$1{\rightarrow}0$ emission with high spectral resolution of 0.21 kms-1 and covers wide galactic plane regions ($18^{\circ}$ < 1 < $55.7^{\circ}$ and -1 < b < $1^{\circ}$). Firstly, we measured the one dimensional power spectrum of 13CO intensity along the galactic longitude and along the galactic latitude. We found the slope of the power spectrum changes around the molecular ring structure and the center of the galactic plane. Secondly, we explored how the power spectral slope is related with the velocity dispersion of supersonic giant molecular clouds in the GRS. Finally, we suggest the turbulent nature of the interstellar medium is connected with star formation activities in spiral arms.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• v.4 no.4
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• pp.249-253
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• 2000

Data obtained from a cruise from 4~12 December, 1998 was analyzed to estimate the mixing effects of wind, surface cooling, and tide. A band denoting a mixing area with a temperature difference of less than 1$^{\circ}C$ between the sea surface and the bottom extended 40~60 km from the coast into the open sea, following 125$^{\circ}$ 30\` E in longitude. This band was divided into two areas; a well-mixed area close to the coast and a stratified region in the open sea. The mixing effect due to the wind was only 2%, yet the mixing effect due to the tides was about 68%. This indicates that surface cooling and tides were the major factors involved in the mixing mechanism on the west coast during the cooling season.

• The Korean Journal of Ecology
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• v.6 no.3
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• pp.208-226
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• 1983

The vegetation of Odongdo island was surveyed over twenty-nine times from April, 1982 to August, 1983. This island is located at 127。46'05'∼127。39'37'E. longitude and 34。40'20'∼34。48'14'N. latitude. The vegetation of this island consisted of 94 families, 261 genera, 314 species, 53 varieties and 6 formae. And among them were 170 species of woody plants and 203 species of herbs. The community of evergreen broad-leaved trees comprised a total of 44 species including Sasa coreana Nakai and camellia japonica L. and the distribution of evergreen broad-leaved trees was good in this island as a whole. Sasa coreana Nakai, Castanopsis cuspidata var. sieboldii Nakai, Ficus erecta Thunb., Ficus nipponica Fr. et Sav, Stauntonia hexaphylla (Thunb.) Decne, Cinnamomum japonicum Sieb., Machilus thunbergii S. et Z., Lozoste lancifolia (S. et Z.) Bl., Ilex intergra Thunb., Camellia japonica Thunb., Hedera rhombea Bean and Ardisia japonica Bl. etc. in this island were autochthonous flora and their preservation is required.