• Title/Summary/Keyword: time-space

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The Status and Plan of KMTNet Operation

  • Lee, Chung-Uk;Kim, Seung-Lee;Lee, Dong-Joo;Cha, Sang-Mok;Lee, Yongseok;Kim, Dong-Jin;Kim, Yunjong;Park, Hong Soo;Kim, Hyun-Woo;Lim, Jin-Sun
    • The Bulletin of The Korean Astronomical Society
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    • v.44 no.1
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    • pp.61.2-61.2
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    • 2019
  • A total of 10,317 hours of the KMTNet telescope time were allocated for the predefined science programs, and 7,765 hours have been used for science exposures in Chile, Australia and South Africa last year. The success rate of science observation has increased from 70.7% to 75.3%, and the system operation rate has also increased from 97.6% to 99.6%. There were many improvements in mechanical parts of the dome structure and telescope system, and newly installed filter driers of the CCD camera increased the stability of the system by preventing contamination of oil in the gas line in advance. In order to prepare for the time domain astronomy and multi messenger astronomy era, a pilot program was designed and is now being tested. It targets for fast follow-up observations of optical transient events, however it runs during twilight times only so it does not interrupt any granted science program. A total of 32 SCI papers were published using the system in 2018 and it is a good indication of the high science performance of KMTNet. The selection process of the next observation programs starting from October 2020 and its timeline will be discussed in this meeting.

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Design and Implementation of Space Time Point for Real-time Public Transportation Route Guidance (실시간 대중교통 경로안내를 위한 Space Time Point 모델의 설계와 구현)

  • Kim, Soo-Ho;Joo, Yong-Jin;Park, Soo-Hong
    • Spatial Information Research
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    • v.20 no.3
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    • pp.83-93
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    • 2012
  • Recent environmental concerns have made interest in environment-friendly transportation means such as walking, biking, and public transportation. However, since it is difficult to move long distance by walking or biking, their scope of application is rather limited. On the other hand, public transportation can solve traffic congestion, a recent social issue, though its usability may depend on its time schedule. Currently available information services on public transportation in the Web do not reflect well such traits of the public transportation; thus, in some cases, they may provide wrong information to end users. To solve such problems and provide information based on timetable of public transportations, this paper proposes a STP(Space Time Point) data model. Unlike existing space-time data models, this model recognizes the bottommost element of an object as a point and structures these points in hierarchical way to define an object. In particular, It can make it possible to implement a variety of dynamic spatial objects changing object information according to time. An objective of this study is to design a STP model for bus and subway based on timetables of public transportation in Daejeon area and builds a system to provide path navigation. With the designed navigation function, a path from the Daejeon National Cemetery to Hannam University was searched by time slot. The result showed that the system provided different paths by time, as the system guided different paths when bus operation was limited in midnight. As existing data model could not provide such results, it is confirmed that the system can provide path navigation based on real-time traffic information. It is expected that based on such functionality, it is possible to provide additional functionalities by applying diverse data models such as real-time transport information or traffic history information.

A Study on Observation Type at the Process of Visual Understanding - Focused on the Lobby in the Public Space - (공간의 시각적 이해과정에 나타난 주시유형에 관한 연구 - 공공공간의 로비를 중심으로 -)

  • Kim, Jong-Ha;Cho, Eun-Kil;Ban, Young-Sun
    • Korean Institute of Interior Design Journal
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    • v.21 no.2
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    • pp.92-100
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    • 2012
  • This study was to examine the pattern of visual interpretation in the process of eye-tracking. I categorized the subjects' observation inclination for analysis so that I could find out which element the user observing the space concentrated and explored. First, for 2 minutes of observation, there occurred 171 times of eye-fixations and 9.8 times of observation frequency on average, which showed that the subject, through this observing fixation, spent 44.5% of the entire time performing the visual activity in order to acquire the "visual understanding" of the lobby-space. Second, I found out that there was a consistent observation type as the time passed. I could categorize the subjects observing the space into 6 concentrating types and 3 discontinuing ones of observation types, which category can be utilized as data for analyzing the subjects' characteristics at space-observation. Third, the type, which was so intensive as to get the visual understanding on the space, was mostly of the case that (1) the subject had a kind of high degree of observation type, exploring the space, again having high degree of the observation type [Type A], (2) the subject repeated the concentration from the early part to the latter [Type C], which can be considered to be the observation type generally shared. Fourth, in the case of observing the space, 45.8% of the subjects showed a high rate of concentration at the time of starting the observation and in less than two minutes. The subjects of type A can be considered to understand the space visually by distinctively repeating the concentration and exploration.

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CME and radio characteristics of making large solar proton events

  • Hwang, Jung-A;Cho, Kyung-Suk;Bong, Su-Chan;Kim, Su-Jin;Park, Young-Deuk
    • The Bulletin of The Korean Astronomical Society
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    • v.35 no.1
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    • pp.33.2-33.2
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    • 2010
  • We have investigated a relationship among the solar proton events (SPEs), coronal mass ejections (CMEs) and solar flares during the solar cycle 23 (1997-2006). Using 63 SPE dataset, we found that SPE rise time, duration time, and decrease times depend on CME speed and SPE peak intensity depends on the CME earthward direction parameter as well as CME speed and x-ray flare intensity. While inspecting the relation between SPE peak intensity and the CME earthward direction parameter, we found that there are two groups: first group consists of large 6 SPEs (> 10,000 pfu at >10 MeV proton channel of GOES satellite) and shows a very good correlation (cc=0.65) between SPE peak intensity and CME earthward direction parameter. The second group has a relatively weak SPE peak intensity and shows poor correlation between SPE peak intensity and the CME earthward direction parameter (cc=0.01). By investigating characteristics of 6 SPEs in the first group, we found that there are special common conditions of the extremely large proton events (group 1); (1) all the SPEs are associated with very fast halo CME (>1400km/s), (2) they are almost located at disk region, (3) they also accompany large flare (>M7), (4) all they are preceded by another wide CMEs, and (5) they all show helmet streamer nearby the main CME. In this presentation, we will give details of the energy spectra of the 6 SPE events from the ERNE/HED aboard the Solar and Heliospheric Observatory (SOHO), and onset time comparison among the SPE, flare, type II burst, and CME.

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A Study on User Competency Training for Building Space Management Platform for Urban Regeneration (도시재생을 위한 건물공간관리 플랫폼 사용자 역량 교육에 관한 연구)

  • Kang, Hyun-joo;Kim, Chee-Yong
    • Journal of Korea Multimedia Society
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    • v.23 no.3
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    • pp.499-507
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    • 2020
  • This paper is one of the types of 'sharing economy', a social economic model that borrows and shares things, spaces, and services from the development of the 4th Industrial Revolution. Through sharing of empty space and time in the city, I would like to suggest a way to reduce the closure of small business owners in order to create jobs, which is one of urban problems in the community. We also build a platform that utilizes the free time and space of buildings through space sharing, one of the types of sharing economy, and provides education programs for start-up education, promotion, marketing, and consulting by matching small business owners with building owners. Therefore, in this paper, by sharing the space and time, the landlord and the small business can share the profits of the small business by reducing the business owner's closure and the job creation plan. Coaching urban regeneration was proposed.

A Study on the Expression of Movement in Architectural Design in the first Machine Age (제1기계시대 건축디자인에서의 운동의 표현에 관한 연구)

  • Kim Won-Gaff
    • Korean Institute of Interior Design Journal
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    • v.14 no.1
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    • pp.28-36
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    • 2005
  • The theme of modern architecture was various expression of dynamism and the flow of space. It was because that the space become the main theme of architecture since the late 19th century, and the space was changed from the 3rd dimension into the 4th dimensional space-time continuum. Though many avant-garde artists in the early 20th century did not understand the theory of relativity, they became conscious of the concept of space-time continuum, and tried to express the movement as the duration in time which Bergson defined. Many architects in the first machine age conceived the movement of architecture, and understand it as the dynamism of the mass and in the space. But especially, Sant'Elia and Hilberseimer expressed it as the flow of various force and vector In the metropolis as entire system. And Some architects conceived it as real movement of the building and expressed it as the rotary motion of building, movable partition and furniture, mobile prefabricated building. This study analyzed the expression of movement in architecture in the first machine age.

Channel Estimation scheme for IEEE 802.11a system based on MIMO-OFDM systems (IEEE 802.11a 기반의 MIMO-OFDM 시스템을 위한 채널 추정 기법)

  • 안치준;안재민
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.29 no.6A
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    • pp.640-650
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    • 2004
  • Channel estimation schemes are proposed for Multiple Input-Multiple output Orthogonal Frequency Division Multiplexing(MIMO-OFDM) systems based on the physical layer specification of the IEEE 802.1 la. By combining the space-time block coding(STBC)/ space-frequency block coding(SFBC) techniques with the transform domain interpolation, the proposed algorithms achieve more accurate channel coefficients for the MIMO channels such that improve the BER performance. The performance improvements of the proposed algorithms are evaluated by simulations under the various multipath fading channel environments and various transmission rates.

A Study on Time & Change in Contemporary Space Design -Their Perceptual.Cognitive Bases and Alfordances on Human Behavior- (현대 공간디자인에 입어 시간성과 변화 - 지각 . 인지적 기제 및 행태지원성을 중심으로 -)

  • 이정민;임진이
    • Korean Institute of Interior Design Journal
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    • no.41
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    • pp.246-255
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    • 2003
  • All art forms are the results of the artist's response to the philosophical, sociological, and cultural tendencies of the period in which the artist lives. Post-modern period differentiates itself from Modern period in many aspects. One of these is the emphasis on phenomena which are ephemeral and changing. This paper looks at the perceptive and cognitive bases of these expressions of change in space design and their affordances on human behavior The first chapter provides the purpose and the background of the research. It studies the philosophical, sociological and cultural characteristics of the Post-modern era which bring forth expressions of time & change in space design. The second chapter explains two basic approaches which can be applied to the perception and cognition of the environment. The third chapter deals with the perceptional and cognitive bases, and the human affordances of the expressions of change in space design. Finally this paper will analyze the types of space design which show this tendency : change by the technology, change by the participation of viewers, and change by the natural and chance. In each type, there will be analyses of examples. this will lead us to the understanding of how the space design including time & change expresses the spirit of the age and how it can play positive roles in human psychology.

Storm-Time Behaviour of Meso-Scale Field-Aligned Currents: Case Study with Three Geomagnetic Storm Events

  • Awuor, Adero Ochieng;Baki, Paul;Olwendo, Joseph;Kotze, Pieter
    • Journal of Astronomy and Space Sciences
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    • v.36 no.3
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    • pp.133-147
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    • 2019
  • Challenging Minisatellite Payload (CHAMP) satellite magnetic data are used to investigate the latitudinal variation of the storm-time meso-scale field-aligned currents by defining a new metric called the FAC range. Three major geomagnetic storm events are considered. Alongside SymH, the possible contributions from solar wind dynamic pressure and interplanetary magnetic field (IMF) $B_Z$ are also investigated. The results show that the new metric predicts the latitudinal variation of FACs better than previous studies. As expected, the equatorward expansion and poleward retreat are observed during the storm main phase and recovery phase respectively. The equatorward shift is prominent on the northern duskside, at ${\sim}58^{\circ}$ coinciding with the minimum SymH and dayside at ${\sim}59^{\circ}$ compared to dawnside and nightside respectively. The latitudinal shift of FAC range is better correlated to IMF $B_Z$ in northern hemisphere dusk-dawn magnetic local time (MLT) sectors than in southern hemisphere. The FAC range latitudinal shifts responds better to dynamic pressure in the duskside northern hemisphere and dawnside southern hemisphere than in southern hemisphere dusk sector and northern hemisphere dawn sector respectively. FAC range exhibits a good correlation with dynamic pressure in the dayside (nightside) southern (northern) hemispheres depicting possible electrodynamic similarity at day-night MLT sectors in the opposite hemispheres.