• Title/Summary/Keyword: Space division

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RF ENVIRONMENT TEST ON A PROPOSED SITE FOR THE SENSOR STATION OF THE NEXT GENERATION SATELLITE NAVIGATION SYSTEM, GALILEO: II. THE RESULT OF THE TEST ON THE CANDIDATE SITE IN THE YEAR OF 2007 BY KASI AND ESA (차세대 위성항법체계 갈릴레오 센서스테이션 유치 후보지 전파 수신환경 조사: II. 실제 예정 부지에 대한 2007년 한국천문연구원과 ESA 공동조사 결과)

  • Jo, Jung-Hyun;Comte, Michel;Gonzalez, Moises;Park, Jong-Uk;Lee, Chang-Hoon;Park, Phil-Ho;Hwang, Jung-Wook;Choe, Nam-Mi
    • Journal of Astronomy and Space Sciences
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    • v.25 no.1
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    • pp.53-60
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    • 2008
  • A RF environmental field test for the proposed Galileo Sensor Station site was done by Alcatel Alenia technical team contracted by European Space Agency (ESA) and the Space Geodesy division of Korea Astronomy and Space Science Institute at the Korean VLBI Hetwork (KVN) site in Tamla University Campus, Jeju from June 21, 2007 to June 24, 2007. Full band and in-band 24 hour observation for radio frequency interference, precise positioning, and multipath on three proposed antenna locations for Galileo signal were executed. The main purpose of this survey is to verify the results of previous test on 2006 by KASI. The preliminary analysis of the results and a full investigation also had been done by ESA under the permission of KASI until the end of July, 2007.

A Comparison of Traditional Living Space Based on Family System In Korea, China and Japen (${\cdot}$${\cdot}$일 가족관계에 따른 전통주거공간 비교연구)

  • Kim Do-Yeon;Oh He-Kyung
    • Journal of Families and Better Life
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    • v.23 no.3 s.75
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    • pp.169-183
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    • 2005
  • The present study purposed to identify differences and similarities in traditional residential space among Korea. China and Japan, which share similar social structure, and to make a comparative analysis on differences in traditional residential space according to family relation in the three countries. For these Purpose, this study selected residences, which are similar to one another in terns of time, class and economy and analyzed them using their floor plans and photographs. The results of this research are as follows. Knrea, China and Japan, all of which have family-centered social structure, separate their residential space from the external society and particularly women's space is placed inside men's space or in a secluded area. The most remarkable characteristic of residential space in Korea is the division of living spare between men and women. Space is allocated according to the hierarchical order of families. In this way, the position or order of family members is reflected in the use of space. Characteristically in China based on the large-family system each family is given a space for independent life. Particularly as the relation among brothers is emphasized, space is allocated equally to all brothers but the status of a space is determined by the order of the residents. Residential space in Japan is organized to emphasize the absolute authority and status of the head of the family. As the space is planned focused on the family head's daily life and guest reception, the relation among other family members is ignored. That is, Japanese residence is a social space for the family head's guest reception, Chinese residence is a family-centered space rather than a social space, and Korean residence accommodates both space for family life and social space.

A Study on planning of storage area considering residents' needs (거주자 요구를 고려한 수납면적에 관한 연구)

  • Lee, Se-Na;Lee, Hyun-Soo
    • Proceedings of the Korean Institute of Interior Design Conference
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    • 2006.05a
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    • pp.193-196
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    • 2006
  • The storage style has changed because of diversity of family types, improvement of cost of living, and increase of leisure time. In spite of this change, storage space has still caused discomfort since it did not consider residents' convenience. Therefore, in this study, Brand Apartments were selected, furniture detail drawing was analyzed by plan of housing size and zone to calculate storage area and capacity, and finally needs of storage space were analyzed using survey. Satisfaction of storage space was generally low and $20{\sim}30%$ increase of storage space was demanded. The reasons why the storage space was not satisfied are followed. First, storage space was insufficient. Second, the inner structure of storage space was unified. According to change of life style, needs have changed. To satisfy these needs, the inner division of storage space is planned with considering various items. In addition, development of hardware, flexible division, and priority of storage space with considering user's convenience are needed.

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13M ANTENNA UPGRADE PLAN FOR FUTURE MISSION

  • Park, Durk-Jong;Yang, Hyung-Mo;Koo, In-Hoi;Ahn, Sang-Il
    • Proceedings of the KSRS Conference
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    • 2007.10a
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    • pp.493-495
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    • 2007
  • Future sub-meter resolution LEO missions require simultaneous dual-polarization downlink and/or multiple channel downlinks in single polarization. Especially, dual-polarization is needed to cope with bandwidth limitation due to high speed data transmission. Current KARI 13m X-Band antenna system needs to be upgraded to cope with such downlink schemes. This paper describes brief discussions on engineering work regarding how to meet the new requirements with minimum impact on current system as well as C&M (Control and Monitoring) software.

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IO BOARD DESIGN OF NEXT GENERATION SATELLITE USING THE SPACE WIRE INTERFACE

  • Kwon Ki-Ho;Kim Day-Young;Choi Seung-Woon;Lee Jong-In
    • Bulletin of the Korean Space Science Society
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    • 2004.10b
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    • pp.223-226
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    • 2004
  • This paper presents a feasibility study of an advanced IO board design for the next generation of low-earth orbit satellites. Advanced IO board design includes sensor interface, NO, D/A, Digital Module, Serial Module etc, and allows to process increasing data rates between IO board and CPU board. The higher data rate involved in modem IO board additionally introduce issues such as noise, fault tolerance, command and data handling, limited pin count and power consumption problems. The experience in KOMPSAT-l and 2 program with this kind of problems resulted in using SMCS chip set, a high speed serial link technology based on IEEE-1355 (Space Wire Protocol) (ESA-ESTEC 2003, Parkes 1999), as a standard for next generation of satellite IO board design.

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Maximum Ratio Transmission for Space-Polarization Division Multiple Access in Dual-Polarized MIMO System

  • Hong, Jun-Ki;Jo, Han-Shin;Mun, Cheol;Yook, Jong-Gwan
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.9 no.8
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    • pp.3054-3067
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    • 2015
  • The phenomena of higher channel cross polarization discrimination (XPD) is mainly observed for future wireless technologies such as small cell network and massive multiple-input multiple-output (MIMO) system. Therefore, utilization of high XPD is very important and space-polarization division multiple access (SPDMA) with dual-polarized MIMO system could be a suitable solution to high-speed transmission in high XPD environment as well as reduction of array size at base station (BS). By SPDMA with dual-polarized MIMO system, two parallel data signals can be transmitted by both vertically and horizontally polarized antennas to serve different mobile stations (MSs) simultaneously compare to conventional space division multiple access (SDMA) with single-polarized MIMO system. This paper analyzes the performance of SPDMA for maximum ratio transmission (MRT) in time division duplexing (TDD) system by proposed dual-polarized MIMO spatial channel model (SCM) compare to conventional SDMA. Simulation results indicate that how SPDMA utilizes the high XPD as the number of MS increases and SPDMA performs very close to conventional SDMA for same number of antenna elements but half size of the array at BS.

Oscillation of a Small Hα Surge in a Polar Coronal Hole

  • Cho, Kyung-Suk;Cho, Il-Hyun;Nakariakov, V.M.;Yurchyshyn, Vasyl B.;Yang, Heesu;Kim, Yeon-Han;Kumar, Pankaj;Tetsuya, Magara
    • The Bulletin of The Korean Astronomical Society
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    • v.44 no.1
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    • pp.53.2-53.2
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    • 2019
  • $H{\alpha}$ surges (i.e. cool/dense collimated plasma ejections) may act as a guide for a propagation of magnetohydrodynamic waves. We report a high-resolution observation of a surge observed with 1.6m Goody Solar Telescope (GST) on 2009 August 26, from 18:20~UT to 18:45UT. Characteristics of plasma motions in the surge are determined with the normalizing radial gradient filter and the Fourier motion filter. The shape of the surge is found to change from a 'C' shape to an inverse 'C' shape after a formation of a cusp, a signature of reconnection. There are apparent upflows seen above the cusp top and downflows below it. The upflows show rising and rotational motions in the right-hand direction, with the rotational speed decreasing with height. Near the cusp top, we find a transverse oscillation of the surge, with the period of ~2 min. There is no change of the oscillation phase below the cusp top, but above the top a phase change is identified, giving a vertical phase speed about 86kms-1. As the height increases, the initial amplitude of the oscillation increases, and the oscillation damping time decreases from 5.13 to 1.18min. We conclude that the oscillation is a propagating kink wave that is possibly excited by an x-point oscillation.

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Characteristics of Ocean Scanning Multi-spectral Imager (OSMI)

  • Cho, Young-Min;Yong, Sang-Soon;Woo, Sun-Hee;Lee, Sang-Gyu;Oh, Kyoung-Hwan;Paik, Hong-Yul
    • Proceedings of the KSRS Conference
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    • 1998.09a
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    • pp.319-324
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    • 1998
  • Ocean Scanning Multispectral Imager (OSMI) is a payload on the Korean Multi-purpose SATellite (KOMPSAT) to perform worldwide ocean color monitoring for the study of biological oceanography. The instrument images the ocean surface using a whisk-broom motion with a swath width of 800 km and a ground sample distance (GSD) of < 1 km over the entire field-of-view (FOV). The instrument is designed to have an on-orbit operation duty cycle of 20% over the mission lifetime of 3 years with the functions of programmable gain/offset and on-board image data storage. The instrument also performs sun calibration and dark calibration for on-board instrument calibration. The OSMI instrument is a multi-spectral imager covering the spectral range from 400 nm to 900 nm using a CCD Focal Plane Array (FPA). The ocean colors are monitored using 6 spectral channels that can be selected via ground commands after launch. The instrument performances are fully measured for 8 basic spectral bands centered at 412nm, 443nm, 490nm, 510nm, 555nm, 670nm, 765nm and 865nm during ground characterization of instrument. In addition to the ground calibration, the on-board calibration will also be used for the on-orbit band selection. The on-orbit band selection capability can provide great flexibility in ocean color monitoring.

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