• Publications of The Korean Astronomical Society
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• v.27 no.4
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• pp.225-230
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• 2012

Supernovae (SN) and supernova remnants (SNRs) play a major role in the life-cycle of interstellar dusts. Fast shock waves generated by SN explosions sweep out the interstellar space destroying dust grains and modifying their physical and chemical properties. The dense, cooling SN ejecta, on the other hand, provide an environment for dusts to condense. Recent space-infrared telescopes have revealed the hidden universe related to these fascinating microscopic processes. In this paper, I introduce the results on stardusts in young core-collapse supernova remnants obtained by AKARI. The AKARI results show diverse infrared characteristics of stardusts associated with SNRs, implying diverse physical/chemical stellar structures and circumstellar environments at the time of explosion.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.1121-1125
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• 2003

In this paper we deal with visual servoing that can control a robot arm with a camera using information of images only, without estimating 3D position and rotation of the robot arm. Here it is assumed that the robot arm is calibrated and the camera is uncalibrated. We use a pinhole camera model as the camera one. The essential notion can be show, that is, epipolar geometry, epipole, epipolar equation, and epipolar constrain. These play an important role in designing visual servoing. For easy understanding of the proposed method we first show a design in case of the calibrated camera. The design is constructed by 4 steps and the directional motion of the robot arm is fixed only to a constant direction. This means that an estimated epipole denotes the direction, to which the robot arm translates in 3D space, on the image plane.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.28-35
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• 2006

Global Flood Alert System (GFAS) is an attempt to make the best use of satellite rainfall data in flood forecasting. The project of GFAS is promoted both by Ministry of Land, Infrastructure and Transport-Japan (MLIT) and Japan Aerospace Exploration Agency (JAXA), under which Infrastructure Development Institute-Japan (IDI) has been working on the development of Internet-based information system and just launched trial run of GFAS in April 2006 on International Flood Network (IFNet) website. The function of GFAS is to connect space agencies and hydrological services/river authorities in charge of flood forecasting and warning by providing global rainfall information in maps, text data e-mails and so on which is produced from binary global rainfall data downloaded from National Aeronautics and Space Administration (NASA) website. Although the effectiveness of satellite rainfall data in flood forecasting and warning has yet to be verified, satellite rainfall is expected to play an important role to strengthen existing flood forecasting systems by diversifying hydrological data source.

• Proceedings of the KSRS Conference
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• 2005.10a
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• pp.745-748
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• 2005

These days, vehicle is evolving from the isolated space of transportation to the third digital life space connected to the information world via wired and wireless internet and in which the various activities are possible. According to this trend, the speed of growth in the development of Telematics technology and standard is being accelerated due to the government's IT839 strategy and market needs in Korea. ETRI, TTA, and the Telematics Standardization Forum play key role in developing domestic Telematics standard of core technology needed by industry in relation with each other. The international standards are mainly developed by de-facto standardization organizations such as OSGi, OMA, ERTICO, etc. currently. In this paper, we discuss the trends and issues in Telematics standardization and future strategy.

• Journal of KSNVE
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• v.8 no.2
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• pp.251-259
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• 1998

The motion of an aircraft landing gear over rough runway at variable speed is nonstationary. In this paper, a method for the computation of nonstationary response variance is presented which uses a state space form for the combination of landing gear and runway excitation. The dynamic characteristics of the landing gear under nonstationary random excitations has also been analyzed using the proposed method. The formulation is for linear systems of arbitrary order and allows any deterministic velocity history. It has been found by a series of simulation that correlation parameter, damping coefficients of landing gear and tire, and velocity profiles play a prominent role on the dynamic characteristics.

• International Union of Geodesy and Geophysics Korean Journal of Geophysical Research
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• v.22 no.1
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• pp.6-23
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• 1994

A disconnection event (DE) of the cometary plasma tail is one of most spectacular phenomena observed in comets. Yet, for years it has remained one of the great unsolved problems I astronomy and space physics. The solar wind is thought to play a major role in the creation of comet plasma tail (type Ⅰ) disconnection events. The goal of this paper is to present a mechanism that explains the disconnection event in terms of the local conditions at the comet. Comparison of the solar wind conditions and 16 DEs in Halley's comet shows that DEs are associated primarily with crossings of the heliospheric sector boundary and apparently not with any other properties of the solar wind, such as a high speed stream[Yi et al., 1994]. A 3-dimensional resistive magnetohydrodynamic simulation in this paper supports this association by showing that only front-side magnetic reconnection between the reversed interplanetary magnetic fields that exist when a comet crosses the heliospheric sector boundary [Niedner and Brandt, 1978] could reproduce the morphology of a DE, including ray formation [Brandt, 1982].

• The Journal of the Acoustical Society of Korea
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• v.19 no.1E
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• pp.38-42
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• 2000

In this paper we studied the reduced subjective timbre space of time-varying tones as well as steady state tones. 45 modified test tones were constructed from the original violin tone in consideration of 4 physical factors: spectrum envelope, inharmonicity, time-varying spectrum and time reversal. The semantic differential (SD) method was used in the listening test. According to the factor analysis, the adjectives can be factorized into 4 groups. The first factor is characterized by the adjectives, 'free', 'broad', 'deep', 'rich', 'strong' and 'reverberant', the second by 'tenor', 'clear', 'bright', 'light' and 'sharp', the third by 'easy', 'smooth', and 'solid', the fourth by 'warm' and 'full'. The first factor, 'richness', seems to be dependent upon the time-varying characteristic of a tone. The second factor, 'sharpness', is shown to play an important role in a time-varying tone as well as in a steady state tone.

• 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.

• Journal of the Korean housing association
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• v.9 no.3
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• pp.47-57
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• 1998

The purpose of this study is to find out the residents' attitudes for the shared community space (SCS) according to various housing sizes (60㎠, 85㎠, 102㎠, 135㎠). The major findings are as follows: 1) The residents' overall trends for the SCS showed that the satisfaction rate and requirement rate according to housing size didn't show a significant difference, but there was a considerable difference among the using rates for each category of housing sizes. 2) The kinds of common facilities that residents required were recreational facilities, car-wash facilities, children's play centers, facilities for separation/sanitation for garbage and recyclable materials and lounging facilities in that order. The common facilities that require tenant-management were recreational facilities, car-wash facilities and lounging facilities in that order. The common facilities that require participation in tenant-management were study/reading facilities, recreational facilities and hobby/lecture facilities in that order. 3) With regard to the residents' needs, the tenant-management and participation in it, the kinds of common facilities were differentiated according to housing size (60㎠, 85㎠, 102㎠, 135㎠).

• Proceedings of the Korean Institute of Interior Design Conference
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• 1999.04a
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• pp.137-140
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• 1999

Children usually have an endless curiosity. They sometimes show us some fanciful, various and unpredictable behaviors and they are always in need of enough space to play in, no matter where it might be. Designers have to provide children with a proper space in which they feel free to diffuse their aspirations. Three samples of apartment site in Cheongju city were selected in order to satisfy the purpose of this survey. To figure out the actual use of playground, the extent of preference and satisfaction and the requests for future betterment, this study used questionnaires, photos, interviews and observations. The conclusions of this survey are as follows and it may be expected that the results suggest a kind of guidance for designing playground on apartment sites.