• Title/Summary/Keyword: space system

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BITSE Instrument

  • Choi, Seonghwan;Park, Jongyeob;Yang, Heesu;Baek, Ji-Hye;Kim, Jihun;Kim, Jinhyun;Kim, Yeon-Han;Cho, Kyung-Suk;Newmark, Jeffrey S.;Gong, Qian;Nguyen, Hanson;Chang, William S.;Swinski, Joseph-Paul A.;Gopalswamy, Natchumuthuk
    • The Bulletin of The Korean Astronomical Society
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    • v.44 no.2
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    • pp.57.2-57.2
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    • 2019
  • BITSE is a balloon mission, which is a solar coronagraph to measure speed and temperature of the solar wind using 4 different wavelength filters and an pixelated polarization camera. KASI and NASA jointly designed, developed, and tested the solar coronagraph. Mainly KASI developed an imaging system and a control system, and NASA developed an optical system and mechanical structures. We mount the BITSE on Wallops Arc-Second Pointer (WASP) of Wallops Flight Facility, and launch it with a 39 mcf balloon of Columbia Scientific Ballon Facility. We will introduce the overall system of the BITSE.

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Library Space Efficiency Improvement Through Closed Access System -Focused on Academic Libraries- (공간효율 개선을 위한 폐가식 도서관 운용 -지역 대학도서관 시설을 중심으로-)

  • Ahn, Joon Suk
    • Journal of the Korean Institute of Rural Architecture
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    • v.18 no.4
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    • pp.17-24
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    • 2016
  • Since the users have direct access to search and browse freely, the open access system has been employed to all the usual modern libraries. However, library space shortage problem created by the continuously increasing printed materials caused the degradation of usability and quality of the library space. Open Access system is superior in user convenience but is inferior in space efficiency. Keeping the open access system is considered as one of the reasons of the space shortage problem. Even though the closed access system does not provide free access or easy browsing for the uses, it's space efficiency is much higher than the open access system. The closed access system should be employed as a plan to relieve space shortage problem. Since the closed access system does not allow the public direct access to books, it is very economical. It also provides much better space efficiency with higher book shelving density. In this article, closed access library system models and their characteristics are examined as the reduction plans for the library space shortage problems.

Separation of Kernel Space and User Space in Zephyr Kernel (Zephyr 커널에서 커널 공간과 사용자 공간의 분리 구현)

  • Kim, Eunyoung;Shin, Dongha
    • IEMEK Journal of Embedded Systems and Applications
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    • v.13 no.4
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    • pp.187-194
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    • 2018
  • The operating system for IoT should have a small memory footprint and provide low power state, real-time, multitasking, various network protocols, and security. Although the Zephyr kernel, an operating system for IoT, released by the Linux Foundation in February 2016, has these features but errors generated by the user code can generate fatal problems in the system because the Zephyr kernel adopts a single-space method that both the user code and kernel code execute in the same space. In this research, we propose a space separation method, which separates kernel space and user space, to solve this problem. The space separation that we propose consists of three modifications in Zephyr kernel. The first is the code separation that kernel code and user code execute in each space while using different stacks. The second is the kernel space protection that generates an exception by using the MPU (Memory Protection Unit) when the user code accesses the kernel space. The third is the SVC based system call that executes the system call using the SVC instruction that generates the exception. In this research, we implemented the space separation in Zephyr v1.8.0 and evaluated safety through abnormal execution of the user code. As the result, the kernel was not crashed by the errors generated by the user code and was normally executed.

A Study of Setting up a Plan for the Open Space System - Kyongju City as the Case Study Area - ("오픈스페이스"체계수립방안에 관한 연구 - 경주시를 연구사례지역으로 -)

  • 홍광표
    • Journal of the Korean Institute of Landscape Architecture
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    • v.13 no.2
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    • pp.99-114
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    • 1985
  • ^x Open space has become the subject o\ulcorner remarkable, new interest ; and many studies have been done recently. In urban pattern, the significance of open space is not its quantity but how it is arranged. The end of this article is to set up a plan for the open space system for Kyongiu city. This paper has three parts : first, a brief discussion of the concept and function of open space ; secondly, a review of open space system ; and finally, a case study of Kyongju City. Especially, this study is focuced on the methodology in conserving and using prototype plan for historic and cultural environment. The result of this study may be summed up as follows : 1) The open space network for kyongju city can be planned out as a belt and ripple pattern. 2) The linear element of open space must play an important role in connecting each element with the whole open space system. 3 ) The Hwangseong pork can be the focal element of the open space system.

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The Design Concept of the First Mobile Satellite Laser Ranging System (ARGO-M) in Korea

  • Jo, Jung-Hyun;Park, In-Kwan;Lim, Hyung-Chul;Seo, Yoon-Kyoung;Yim, Hong-Seo;Lee, Jin-Young;Bang, Seung-Cheol;Nah, Ja-Kyoung;Kim, Kwang-Dong;Jang, Jeong-Gyun;Jang, Bi-Ho;Park, Jang-Hyun;Park, Jong-Uk
    • Journal of Astronomy and Space Sciences
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    • v.28 no.1
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    • pp.93-102
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    • 2011
  • Korea Astronomy and Space Science Institute (KASI) launched the development project of two satellite laser ranging (SLR) systems in early 2008 after the government fund approval of the SLR systems in 2007. One mobile SLR system and one permanent SLR station will be developed with the completion of the project. The main objectives of these systems will be focused on the Space Geodetic researches. A system requirement review was held in the second half of the same year. Through the following system design review meeting and other design reviews, many unsolved technical and engineering issues would be discussed and resolved. However, the design of the mobile SLR system is a corner stone of whole project. The noticeable characteristics of Korea's first SLR system are 1) use of light weight main mirror, 2) design of compact optical assembly, 3) use of KHz laser pulse, 4) use of commercial laser generator, 5) remote operation capability, 6) automatic tracking, 7) state of art operation system, etc. In this paper, the major user requirement and pre-defined specification are presented and discussed.

Analysis of Maritime-based Space Capabilities of Major Countries and Future Direction for South Korea (주요국의 해상기반 우주능력 분석 및 한국의 발전방향)

  • Cho, Taehwan;Lee, Soungsub
    • Journal of Advanced Navigation Technology
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    • v.25 no.3
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    • pp.242-247
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    • 2021
  • Major countries in space field such as the United States, China and Russia have not only general ground-based space capabilities, but also maritime-based space capabilities. Maritime-based space systems include a maritime-based space surveillance system, a maritime-based space launch vehicle, and a maritime-based space information transmission system, and these maritime-based systems complement the ground-based space systems. Therefore, in this paper, we analyze the maritime-based space capabilities of major countries, and propose the future direction for south Korea's maritime-based space capabilities. The maritime-based space system is essential due to the geographical characteristics of south Korea, which has three sides of the ocean, and it is considered an one of important strategic element to become the seven major country in the space field.

Development of Optical System for ARGO-M

  • Nah, Jakyoung;Jang, Jung-Guen;Jang, Bi-Ho;Han, In-Woo;Han, Jeong-Yeol;Park, Kwijong;Lim, Hyung-Chul;Yu, Sung-Yeol;Park, Eunseo;Seo, Yoon-Kyung;Moon, Il-Kwon;Choi, Byung-Kyu;Na, Eunjoo;Nam, Uk-Won
    • Journal of Astronomy and Space Sciences
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    • v.30 no.1
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    • pp.49-58
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    • 2013
  • ARGO-M is a satellite laser ranging (SLR) system developed by the Korea Astronomy and Space Science Institute with the consideration of mobility and daytime and nighttime satellite observation. The ARGO-M optical system consists of 40 cm receiving telescope, 10 cm transmitting telescope, and detecting optics. For the development of ARGO-M optical system, the structural analysis was performed with regard to the optics and optomechanics design and the optical components. To ensure the optical performance, the quality was tested at the level of parts using the laser interferometer and ultra-high-precision measuring instruments. The assembly and alignment of ARGO-M optical system were conducted at an auto-collimation facility. As the transmission and reception are separated in the ARGO-M optical system, the pointing alignment between the transmitting telescope and receiving telescope is critical for precise target pointing. Thus, the alignment using the ground target and the radiant point observation of transmitting laser beam was carried out, and the lines of sight for the two telescopes were aligned within the required pointing precision. This paper describes the design, structural analysis, manufacture and assembly of parts, and entire process related with the alignment for the ARGO-M optical system.

Operation of the Radio Occultation Mission in KOMPSAT-5

  • Choi, Man-Soo;Lee, Woo-Kyoung;Cho, Sung-Ki;Park, Jong-Uk
    • Journal of Astronomy and Space Sciences
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    • v.27 no.4
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    • pp.345-352
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    • 2010
  • Korea multi-purpose satellite-5 (KOMPSAT-5) is a low earth orbit (LEO) satellite scheduled to be launched in 2010. To satisfy the precision orbit determination (POD) requirement for a high resolution synthetic aperture radar image of KOMPSAT-5, KOMPSAT-5 has atmosphere occultation POD (AOPOD) system which consists of a space-borne dual frequency global positioning system (GPS) receiver and a laser retro reflector array. A space-borne dual frequency GPS receiver on a LEO satellite provides position data for the POD and radio occultation data for scientific applications. This paper describes an overview of AOPOD system and operation concepts of the radio occultation mission in KOMPSAT-5. We showed AOPOD system satisfies the requirements of KOMPSAT-5 in performance and stability.

A Study on the Enhancement of Detection Performance of Space Situational Awareness Radar System

  • Choi, Eun-Jung;Lee, Jonghyun;Cho, Sungki;Moon, Hyun-Wook;Yum, Jea-Myong;Yu, Jiwoong;Park, Jang-Hyun;Jo, Jung Hyun
    • Journal of Astronomy and Space Sciences
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    • v.35 no.4
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    • pp.279-286
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    • 2018
  • Radar sensors are used for space situational awareness (SSA) to determine collision risk and detect re-entry of space objects. The capability of SSA radar system includes radar sensitivity such as the detectable radar cross-section as a function of range and tracking capability to indicate tracking time and measurement errors. The time duration of the target staying in a range cell is short; therefore, the signal-to-noise ratio cannot be improved through the pulse integration method used in pulse-Doppler signal processing. In this study, a method of improving the signal-to-noise ratio during range migration is presented. The improved detection performance from signal processing gains realized in this study can be used as a basis for comprehensively designing an SSA radar system.

Design of an Embedded Linux File System with LZSS Algorithm for the PDA System (LZSS 압축 알고리즘을 적용한 PDA용 Embedded Linux 파일 시스템 설계)

  • Jang Seung-Ju
    • The KIPS Transactions:PartA
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    • v.13A no.2 s.99
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    • pp.95-100
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    • 2006
  • I design an Embedded File System in Linux Operating System by applying modified LZSS compressed algorithm. This suggested Compressed File System which is modified file system of the Linux O.S saves the storage space. The compressed file system supports efficient use of storage space. The suggesting file system solves the small space of embedded system. The suggesting file system of this paper gives effect of the large storage space without extending the storage space.