• The Bulletin of The Korean Astronomical Society
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• v.43 no.1
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• pp.67.2-67.2
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• 2018

Magnetic fields play an important role in star-forming processes by regulating gravitational collapse. In filamentary structures of star-forming regions, magnetic fields are likely to be aligned with minor axes of filamentary molecular clouds because matter freely moves along magnetic field lines. Orion A region, one of the well-known high-mass star forming regions, has long filament structure. In order to study magnetic field directions with respect to the filamentary structure in Orion A, we have analyzed $850{\mu}m$ dust polarization observations obtained with the James Clerk Maxwell Telescope (JCMT). We found tight correlation of dust intensity gradients and magnetic field directions. It was estimated that 81% of magnetic field segments are aligned with density gradients within 40 degree. In conclusion, we confirmed most of magnetic field segments are perpendicular to the major axis of the filament in Orion A.

• Culinary science and hospitality research
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• v.10 no.3
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• pp.18-31
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• 2004

Korean food industry has been developed while it receives footlights as the most encouraging industry and composing one axis of food industry under various marketing activities and severe competitions. The purpose of this study was to understand customer's reason to use bakery, extract important factor, systematically analyze and suggest the direction of bakery industry through study on the character of bakery-user. The researcher Modified the Questionnaire developed by Yoon, YH(2000) & Kim, SE(2002). The major findings obtained from this study were as follows. First, on factors of confidence and propriety, price and communication with consumers, product and service, and service response, there was a high difference between male and female. Second, on factors of accessibility & product and service, there was a high difference among disparity of age. Third, on item of confidence and propriety, there was a high difference among customers' residing styles. Fourth, in relation to income level, there was statistically no difference.

• Journal of Astronomy and Space Sciences
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• v.3 no.1
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• pp.53-66
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• 1986

Isophotes and surface brightness distribution were obtained for the late type normal spiral galaxy NGC 7793 (morphological type SA(s)d) which is one of the Sculptor group. The calculated total luminosity $M_{T}$ is obtained as 9.44 and the corrected face on magnitude ${B_T}^{circ}$ is 9.10. The revised distance to this galaxy $\Delta$=3.1 Mpc (de Vaucouleurs and Davoust 1980) is used for calculating the absolute magnitude ${M_T}^{circ}$ = -18.36. From the isophotes, the position angle to the major axis is $101^{circ}$, the mean axial ratio is q=b/a =0.65, and the inclination is i=50$^{circ}$. The concentric indices $C_{21}$=1069 and $C_{32}$ =1.50 are well agreed to the average value of Sd type galaxies.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.05a
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• pp.220-226
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• 2002

A general solution method is presented to obtain the unbalance response orbit from the finite element based equations of motion of a gear-coupled two-shaft rotor-bearing system. Particularly, are proposed the analytical solutions of major and minor axis radii of the orbit. The method has been applied to analyze the unbalance response of a 800 refrigeration-ton turbo-chiller rotor-bearing system, having a bull-pinion speed increasing gear. The bumps of unbalance responses have been observed at the first torsional natural frequency due to the coupling of lateral and torsional dynamics by the gear meshing. Further, the proposed analytical solutions have been validated with results obtained by a full numerical approach.

• Journal of the Korean Vacuum Society
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• v.8 no.1
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• pp.26-30
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• 1999

Sputter deposited Co-Cr thin films been developed continuously as one of the major candidates for high density recording media. In this study, Co-26at%Cr thin films with c-axis oriented normal to substrate surface were prepared by a improved facing targets sputtering system. We find that the effect of microstructural changes of the sputtered Co-Cr thin films on magnetic properties and changes of crystal orientation due to the variation of substrate temperature.

• Development and Reproduction
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• v.16 no.1
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• pp.1-8
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• 2012

The reproduction of animals is a way to maintain their species and demands a large amount of energy. The golden hamsters are seasonal breeders whose reproductive activities are regulated by photoperiod (length of day time in a day). The photic information received is transported to the pineal gland via many steps. Melatonin produced by the pineal gland affects the reproductive neuroendocrine system to manage reproductive activities. The major regulator neurons, secreting gonadotropin-releasing hormone, integrate all kinds of information to govern the reproductive frame hypothalamuspituitary-gonad axis. The elements impinging on the neurons are recently outspread. Thus the present review is to briefly survey the elements discovered newly and subjected to the active research realm and their correlations, focusing on the regulation of reproduction in mainly male golden hamsters as a representative animal.

• Journal of The Korean Astronomical Society
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• v.36 no.4
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• pp.261-270
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• 2003

We have conducted a V-band CCD surface photometry of 68 disk galaxies to analyze the bulge morphology of nearby spirals. We classify bulges into four types according to their ellipticities and the misalignments between the major axis of the bulge and those of the disk and the bar: spherical, oblate, pseudo triaxial, and triaxial. We found that one third of the bulges are triaxial and they are preponderant in barred galaxies. The presence of the triaxial bulges in a significant fraction of unbarred galaxies as well as in barred galaxies might support the secular evolution hypothesis which postulates that the bar driven mass inflow leads to the formation of triaxial bulges and the destruction of bars when sufficient mass is accumulated in the central regions.

• Journal of ILASS-Korea
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• v.23 no.1
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• pp.9-15
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• 2018

Breakup lengths of circular and elliptical liquid jets in a subsonic crossflow were experimentally studied. Two circular-shaped and four elliptical-shaped plain-orifice injectors, which had different aspect ratios and orifice length to diameter ratios, were used to provide various liquid jet conditions such as steady, cavitation, and hydraulic flip. By varying the injection pressure drop from 1 bar to 6 bar, spray images were taken using a shadowgraph technique. Breakup lengths were measured and analyzed. As the aspect ratio in orifices increased, liquid column breakup lengths normalized by the equivalent diameter were reduced irrespectively of the switching of the major or minor axis to the crossflow. It was also found that when hydraulic flip developed inside the orifice, x-directional breakup lengths more decreased for both circular and elliptical liquid jets.

• The KSFM Journal of Fluid Machinery
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• v.19 no.4
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• pp.43-47
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• 2016

Vertical axis wind turbine, despite of its limit in power efficiency, the simplicity in structure and maintenance is a competitive factor that keeps this type of turbine in the game until nowadays. Continuous solutions have been given to handle its major weakness and the use of omni-directional guide vane is an considerable one. In this paper, a 5kkW scale Savonius-based wind turbine enhanced with such guide vane system was design and studied. Together with reasonable blade design, the wind turbine shows promising performance compared with basic design while maintaining its original advantages.

• BMB Reports
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• v.42 no.8
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• pp.475-481
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• 2009

Emerging data demonstrate pivotal roles for brain insulin resistance and insulin deficiency as mediators of cognitive impairment and neurodegeneration, particularly Alzheimer's disease (AD). Insulin and insulin-like growth factors (IGFs) regulate neuronal survival, energy metabolism, and plasticity, which are required for learning and memory. Hence, endogenous brain-specific impairments in insulin and IGF signaling account for the majority of AD-associated abnormalities. However, a second major mechanism of cognitive impairment has been linked to obesity and Type 2 diabetes (T2DM). Human and experimental animal studies revealed that neurodegeneration associated with peripheral insulin resistance is likely effectuated via a liver-brain axis whereby toxic lipids, including ceramides, cross the blood brain barrier and cause brain insulin resistance, oxidative stress, neuro-inflammation, and cell death. In essence, there are dual mechanisms of brain insulin resistance leading to AD-type neurodegeneration: one mediated by endogenous, CNS factors; and the other, peripheral insulin resistance with excess cytotoxic ceramide production.