• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.1
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• pp.22-32
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• 2011

In this paper, we first analyze the differences of underwater acoustic (UWA) orthogonal frequency division multiplexing (OFDM) systems and conventional terrestrial OFDM system, and give a simple introduction of the backgrounds. By considering the real UWA channel environments, the measured channel data is used to generate the UWA channel model and calculate the relative parameters for underwater OFDM systems. Practical least square (LS) based channel estimation with linear interpolation are adopted to obtain the channel state information (CSI) at receiver side. As multi-input multi-output (MIMO) processing techniques, Alamouti code is implemented and evaluated to perform for space time block coding (STBC) and space frequency block coding (SFBC) for UWA OFDM systems with the MIMO configuration of $2{\times}1$, at the same time, $1{\times}2$ maximum ratio combining (MRC) is performed for the purpose of comparison. The simulation results show that, with perfect channel estimation, SFBC failed to work duo to the serious frequency selectivity of UWA channel environments. When the practical channel estimation is applied, in the case of STBC, the proposed 4-column pilot pattern gives better performance about 7dB than SISO system.

• Bulletin of the Korean Space Science Society
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• 2008.10a
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• pp.27.1-27.1
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• 2008

KASI (Korea Astronomy and Space Science Institute) is developing a compact wide-field survey space telescope system, MIRIS (The Multi-purpose IR Imaging System) to be launched in 2010 as the main payload of the Korea Science and Technology Satellite 3. Through recent System Design Review (SDR) and Preliminary Design Review (PDR), most of the system design concept was reviewed and confirmed. The near IR imaging system adopted short F/2 optics for wide field low resolution observation at wavelength band 0.9~2.0 um minimizing the effect of attitude control system. The mechanical system is composed of a cover, baffle, optics, and detector system using a $256\times256$ Teledyne PICNIC FPA providing a $3.67\times3.67$ degree field of view with a pixel scale of 51.6 arcsec. We designed a support system to minimize heat transfer with Muti-Layer Insulation. The electronics of the MIRIS system is composed of 7 boards including DSP, control, SCIF. Particular attention is being paid to develop mission operation scenario for space observation to minimize IR background radiation from the Earth and Sun. The scientific purpose of MIRIS is to survey the Galactic plane in the emission line of Pa$\alpha$ ($1.88{\mu}m$) and to detect the cosmic infrared background (CIB) radiation. The CIB is being suspected to be originated from the first generation stars of the Universe and we will test this hypothesis by comparing the fluctuations in I (0.9~1.2 um) and H (1.2~2.0 um) bands to search the red shifted Lyman cutoff signature.

• Journal of the Korean Professional Engineers Association
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• v.41 no.2
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• pp.40-44
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• 2008

The construction of korea grand canal supplys nation as below:$\Delta$ return to clean and clear river $\Delta$ offer urbanite space for re-charging $\Delta$ offer local resident tourist attractions $\Delta$ alternative for global warming $\Delta$ economic project for development and growth $\Delta$ awake sleeping inland city $\Delta$ strengthen business competitiveness $\Delta$ reduction of logistic cost

• Journal of Ocean Engineering and Technology
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• v.28 no.5
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• pp.429-439
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• 2014

The target echoes contain information on the target such as the orientation, kinematics, and internal structure, as well as the external geometrical shape of the target. In addition, the pattern of the target echoes depends on the arrangement of the transmitters and receivers in space. Therefore, the study of the target echoes in a multi-static SONAR system can be useful for detecting and tracking submerged objects using an underwater surveillance system. For this purpose, an acoustic measuring system for multi-static target echoes was designed and tested in an acoustic water tank. Some preliminary data are presented and discussed.

• KIEAE Journal
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• v.8 no.1
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• pp.11-18
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• 2008

The purpose of this study is to analyze application methods and structural characteristics of each element of environment-friendly European housing through classification of skin types. The results of the study are following. 1) The skins are classified by three types; single skin with multi layers, double skin with single layer and double skin with multi layers. 2) Most single skins with multi-layer are composed with wooden louvers, sun blinds and insulating windows. There are introduction of atrium and balcony, and variation sectional space composition according to cases. 3) There are two types of double skins; to put cavity between inner skin and outer skin and more extensional spaces such as balconies, corridors and stair halls. Solar walls and mechanical ventilators are often introduced to double skins with multi-layer. 4) The functions of the latest environment-friendly skins are vary from controllers and buffers of indoor environmental elements such as temperature, light, air and sound to equipments to perform essential functions to efficiently operate HVAC systems.

• Journal of the Korean housing association
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• v.23 no.1
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• pp.9-17
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• 2012

The purpose of this study is to understand the factors that influence residents' satisfaction with their housing. Resident's satisfaction is mainly influenced by two factors - one that pertains to housing and the other as per characteristics of the individual. Housing-related factors include housing types, housing tenure types, and size of floor space. Individual-related factors include household income, size, and education level. This study shows how both factors influence residents' satisfaction. Residential satisfaction is affected by the type of housing tenure (own, chonsei and monthly rent) and housing (detached housing, apartment and multi-family housing). Residential satisfaction of home owners is greater than that of chonsei renters or monthly renters. Residential satisfaction of chonsei renters is greater than that of monthly renters. Satisfaction of apartment residents is far greater than that of detached housing residents or multi-family housing residents. There is no difference in residential satisfaction between detached housing and multi-family housing residents. As total household labor income, household member, and residential area increase, residential satisfaction increase. Residential satisfaction of countryside residents is greater than that of metropolitan residents.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.28 no.3
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• pp.7-25
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• 2017

The problem of library space has long been discussed in various aspects such as library relations, architecture, and space design. The purpose of this study is to examine the change of the concept of the complex space of the library according to the development of advanced technology and the social paradigm, and to present the direction of constructing the complex space of the future library by analyzing each case. All concepts such as mediatheque, information commons, larchiveum, and the maker space that is recently introduced into the library are important elements of the complex space presented as a problem of library construction and space. The future library reflects these concepts and serves as a mediator between information and users, users and users, users and media to support reading, information, learning, rest, community-oriented culture and creation, start-up and collaboration. It should be constructed as a multi-space platform to create new value through.

• Korean Institute of Interior Design Journal
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• v.18 no.5
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• pp.175-182
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• 2009

Korea Protestant slower growth and social church's changes in the environment of the traditional worship center for the sermon to a variety of changes was required, because of this period reflects the availability of a new type of worship was to appear. These changes in the type of worship in the form of the worship space, and space configuration is affecting many more. This study was the type of church korea today, the type is classified as a traditional worship and contemporary worship, and to characterize the category by a change in the type of church worship space in the configuration that affects cases throughout the analysis was to investigate, study follows. Traditional worship the center of the altar, the altar placed platform form, a vertical elevation of the platform sheet form, the installation of the cross, place the side of the choir seats, church chair type attribute appears tradition and in part compressed pulpit appears symbolism. Contemporary worship to the exclusion of the symbolic elements of the platform open, flat sheet form and the platform was the preferred form of minor elevations of the flat, multi-purpose space used for worship to sermon platform placed around the altar of the adjustable type, the choir seats placed in scheelite, preferred form of scheelite was an individual chair. However, the characteristics of traditional and contemporary worship space features a mix of worship space, quite a lot of cases that have been found. Integrated and consistent element of the worship space, the worship of the discrepancy in the form of systematic theological depth analysis did not come true without lust about contemporary culture is changing rapidly to accommodate sprawl is judged. Therefore, the characteristics of the type of worship and prayer to understand the changes in the church building is a prerequisite to be a very important aspect.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.2
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• pp.78.2-78.2
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• 2014

MIRIS (Multi-purpose Infrared Imaging System) is the primary payload on the Korean science and technology satellite, STSAT-3, which was launched on 2013 November 21. It is designed to observe the near-infrared sky with a $3.67^{\circ}{\times}3.67^{\circ}$ field of view and a $51.6^{{\prime}{\prime}}{\times}51.6^{{\prime}{\prime}}$ pixel resolution. Using two narrow-band filters at $1.88{\mu}m$ (Pa ${\alpha}$ line) and $1.84+1.92{\mu}m$ (Pa ${\alpha}$ dual continuum), the Paschen ${\alpha}$ Galactic plane survey has been carrying out, and the area for the Galactic longitude from $+280^{\circ}$ to $+100^{\circ}$ (with the width of $-3^{\circ}$ < b < $+3^{\circ}$) has been covered by 2014 August 31. In this contribution, we present the preliminary results of the MIRIS Paschen ${\alpha}$ emission maps and compare them with other wavelength maps such as $H{\alpha}$ and dust maps. Many of the Paschen ${\alpha}$ features have been detected along the plane, and some of them are weak or invisible in the $H{\alpha}$ map and coincide well with dense cloud regions.

• Publications of The Korean Astronomical Society
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• v.27 no.3
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• pp.39-47
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• 2012

MIRIS, Multi-purpose Infra-Red Imaging System, is the main payload of STSAT-3 (Korea Science & Technology Satellite 3), which will be launched in the end of 2012 (the exact date to be determined) by a Russian Dnepr rocket. MIRIS consists of two camera systems, SOC (Space Observation Camera) and EOC (Earth Observation Camera). During a shock test for the flight model stability in the launching environment, some lenses of SOC EQM (Engineering Qualification Model) were broken. In order to resolve the lens failure, analyses for cause were performed with visual inspections for lenses and opto-mechanical parts. After modifications of SOC opto-mechanical parts, the shock test was performed again and passed. In this paper, we introduce the solution for lens safety and report the test results.