• The Bulletin of The Korean Astronomical Society
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• v.35 no.1
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• pp.32.1-32.1
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• 2010

KASI's Solar and Space Weather Research Group (SSWRG) is actively involved in solar and space weather research. Since its inception, the SSWRG has been utilizing ground-based assets for its research, such as the Solar Flare Telescope, Solar Imaging Spectrograph, and Sunspot Telescope. In 2007 SSWRG initiated the Korean Space Weather Prediction Center (KSWPC). The goal of KSWPC is to extend the current ground observation capabilities, construct space weather database and networking, develop prediction models, and expand space weather research. Beginning in 2010, SSWRG plans to expand its research activities by collaborating with new international partners, continuing the development of space weather prediction models and forecast system, and phasing into developing and launching space-based assets. In this talk, we will report on KASI's recent activities of international collaborations with NASA for STEREO (Solar Terrestrial Relations Observatory), SDO (Solar Dynamic Observatory), and Radiation Belt Storm Probe (RBSP).

• The Bulletin of The Korean Astronomical Society
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• v.43 no.1
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• pp.56.1-56.1
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• 2018

Tidal disruption events (TDEs) provide evidence for quiescent supermassive black holes (SMBHs) in the centers of inactive galaxies. TDEs occur when a star on a parabolic orbit approaches close enough to a SMBH to be disrupted by the tidal force of the SMBH. The subsequent super-Eddington accretion of stellar debris falling back to the SMBH produces a characteristic flare lasting several months. The theoretically expected bolometric light curve decays with time as proportional to $t^{-5/3}$. However, the light curves observed in most of the optical-UV TDEs deviate from the $t^{-5/3}$ decay rate especially at early time, while the light curves of some soft-X-ray TDEs are overall in good agreement with the $t^{-5/3}$ law. Therefore, it is required to construct the theoretical model for explaining these light curve variations consistently. In this paper, we revisit the mass fallback rates analytically and semi-analytically by taking account of the structure of the star, which is simply modeled by the polytrope. We find the relation between a polytropic index and the power law index of the mass fallback rate. We also discuss whether and how the decay curves, which we derived, fit the observed ones.

• Journal of Acupuncture Research
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• v.20 no.1
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• pp.244-253
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• 2003

Objective : Interferon-alpha and Rivabirin are much used at the same time to treat Chronical C viral hepatitis. But interferon caused lots of unexpected side effects, Acupuncture Treatment for them will be an alternative plan. Methods : We first posed questions to a 4 year-old man who ha skin flare, fatigue, itching, insomnia, pronounced a diagnosis based on overall of symptoms and signs and then treated Acupuncture, Moxibustion and Electroacupuncture. We acupunctured a BL17, BL18, BL20 and removed it at once. We electroacupunctured at GV20, Yin tang(Ex-HN3) form 20 minutes, acupunctured at Bi yi(鼻翼, Extra-point), S36, P6. Pizhengge(脾定格) was acupunctured for 10 minutes. Results : The symptoms of fatigue, insomnia, itching are reduced after acupuncture treatments and they made a person keep interferon treatment on. Conclusions : We confirmed that acupuncture treatments make a patient of chronic C viral hepatitis reduce and improve side effects of interferon treatment. We should keep on studying the various and efficient method of acupuncture treatment to improve living quality and treatment efficiency of patients.

• Journal of the Korean Society of Costume
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• v.58 no.2
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• pp.149-161
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• 2008

The purpose of this study is to consider the origin and kinds of tango and to analyze formative characteristics of tango dance costume. On the basis of the review of literature about tango, photos of tango dance and modern fashion collections designed by tango themes are analysed to examine design elements which are essentially considered in dance costume design. The result of this study are as follows: This study shows the different characteristics of tango dance costume depend on the kind of tango. In case of Argentina tango, sheath silhouette dress and black color are preferred, for Continental tango, fit and flare silhouette which gives convenient movement in dress and white color emphasize the elegant movement are preferred. America tango accentuates the body movement by fitted silhouette, metallic materials, and bead trimmings in dress. The result of the analysis of recent fashion collection shows that characteristics especially strong and sensual tango are mainly an inspiring motive and reinterpreted by designers in modern fashion.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.1B
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• pp.112-119
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• 2000

A two-color infrared (IR) seeker employs two detection-bands for efficient target tracking under countermeasures and background noises. This paper describes a study on the detection-band selections for the two-color seeker. To select the detection-bands, we analysis infrared radiation characteristics of a target, a flare, and background noises and then other characteristics closely related with the received power, such as the atmospheric transmission, acquisition range, background noise effect, and signal-to-noises. The analysis shows that the pertinent bands of two-color IR seeker are 3 um~5 um for target detection and 1.5 um~l.7 um for counter-countermeasures. The results of our study will play a significant role in the further study of two-color seekers.

• Atmosphere
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• v.20 no.3
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• pp.333-341
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• 2010

The stratiform rain fraction is investigated in the tropical boreal winter Madden-Julian oscillation (MJO) and summer intraseasonal oscillation (ISO) using Tropical Rainfall Measuring Mission (TRMM) Precipitation Rader data for the 11-yr period from 1998 to 2008. Composite analysis shows that the MJO/ISO produces larger stratiform rain rate than convective rain rate for nearly all phases following the propagating MJO/ISO deep clouds, with the greatest stratiform rainfall amount when the MJO/ISO center is located over the central-eastern Indian Ocean and the western Pacific. The fraction of the intraseasonally filtered stratiform rainfall compared to total rainfall (i.e., convective plus stratiform rainfall) amounts to 53~56%, which is 13~16% larger than the stratiform rain fraction estimated for the same data on seasonal-to-annual time scales by Schumacher and Houze. This indicates that the MJO/ISO exhibits the organized rainfall process which is characterized by the shallow convection/heating at the incipient phase and the subsequent flare-up of strong deep convection, followed by the development of stratiform clouds at the upper troposphere.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.30 no.5
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• pp.41-47
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• 2002

In this paper, a guidance law applicable to aircraft automatic landing is proposed and its performance is compared with the conventional ILS-type landing approach. The concept of miss distance, which is commonly used in the missile guidance laws, and Lyapunov stability are effectively combined to obtain the landing guidance law. The new landing guidance law is integrated into the existing controller and is applied to the landing approach and flare phases of landing procedure. Numerical simulation results show that the new landing guidance law is a viable alternative to the conventional strategies that directly control the longitudinal deviation or altitude.

• Laser Solutions
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• v.8 no.1
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• pp.27-37
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• 2005

During laser spot welding of the braun tube electron gun, phenomena such as serious spattering and oxidative reaction, etc. were occurred. The spatter occurred from weld pool affects the braun tube, namely it blocks up a very small hole on the shadow mask and causes short circuit between two poles of the electron gun. We guessed that high power density and oxidative reaction are main sources of these problems. So, we studied to prevent and to reduce spatter occurring in spot welding of the braun tube electron gun using pulsed Nd:YAG laser. The characteristics of laser output power was estimated, and the loss of laser energy by optical parameter and spatter was measured by powermeter. The effects of welding parameters, laser defocused distance and incident angle, were investigated on the shape and penetration depth of the laser welded bead in flare and flange joints. From these results, the laser peak power was a major factor to control penetration depth and to occur spatter. It was found that the losses of laser energy by optic parameter and sticked spatter affect seriously laser weldability of thin sheets.

• Journal of Fashion Business
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• v.18 no.2
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• pp.54-65
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• 2014

This study developed basic pattern for competition figure skating wear for school girls. Figure skating wears are difficult for making basic patterns based on standard size chart, because girls' body size are slimmer and more slender compared to the general girl's and the competition wears such as, swim suit with sleeves are, closely in contact with the player's body. The competition wears for school girl was made with consideration of changing of the body shape, physical exercises, and various specificities according to stretch material. To raise artistic effect while doing beautiful motions, and to assist in facile technique motions, competition wears need to have enough ease on the side line from waist to armpit, from armpit to wrist, and in trunk girth including crotch girth. Also, to stand out in beauty, a costume designing has a proper skirt position, length, flare width, and a tight bodice according to the player's body proportion. Most of the customers are displeased at the high price, unfitness of size, insufficient design, and difficulty in access, since they are not sold in sporting goods store. Therefore, a competition wear's basic pattern was made through scientific and emotional process including concerns on material properties, room for activities, and ideal body proportion. Systemizing the basic patterns of production method will solve high repairing expenses, unsuitable sizing, and improve accessibility for purchase.

• Journal of Fashion Business
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• v.12 no.2
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• pp.42-58
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• 2008

The purpose of this study is to examine actual design cases of decorative detail in the Art Nouveau style from the end of 19th century to the beginning of 20th century, and create designs and fashion works to meet our contemporary fashion trends by means of over-decorative style, a characteristic of decorative detail. The characteristics of decorative detail in the Art Nouveau style can be outlined as follows: First, pleats appear with two major feels of solidity, undulated and curvilinear solidity based on gather(ruffle, frill/ flare and flounce) and regular and linear solidity based on linear pleats or tucks. Second, embroidery appears in various patterns developed with stitch of solid feel as well as a variety of coloration effects. Third, attachments are expressed by means of independent motif(applique, gloss effects(beads, sequins), affluent texture and mobility(fur, feather). Moreover, according to technical characteristics and expressive aspects of pleats, embroidery and attachments, it is found that decoration detail in the era of Art Nouveau is over-decoration style. Indeed, it appears in major expressive aspects such as rhythmical solid type, detailed prominence type, superficial touch type and profound volume type.