• Title/Summary/Keyword: space plane

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Numerical Simulation of Nitrogen Discharge at Medium Pressure between Point-Plane Electrodes (침-평판 전극 사이에서 중간 압력 질소 방전의 시뮬레이션)

  • Koh, Wook-Hee;Park, In-Ho
    • Journal of the Korean Vacuum Society
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    • v.17 no.6
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    • pp.487-494
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    • 2008
  • The numerical simulation of point-to-plane discharge of nitrogen at medium pressure has been achieved by a quasi-2d numerical model. In the model, we calculate the distributions of electric charges which are varying as temporal and space and determine the electric field depending on space charge distribution by solving Poisson's equation. The continuity equations are treated numerically by using FCT (Flux-Corrected Transport) Algorithm and FEM (Finite Element Method). The numerical simulation results make us to understand the physical characteristics of nitrogen discharge at 50 torr. The comparison with experimental results[1] shows a good qualitative agreement.

Stress Intensity Factor for an Interface Crack of a Piezoelectric Medium Bonded Between an Elastic Layer and a Half-Space (탄성층과 반무한체 사이에 접합된 압전재료의 계면균열에 대한 응력강도계수)

  • Jeong, Kyoung-Moon;Lim, Chun-Ki;Beom, Hyeon-Gyu
    • Journal of the Korean Society for Precision Engineering
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    • v.19 no.5
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    • pp.81-88
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    • 2002
  • An interface crack of a piezoelectric medium bonded between an elastic layer and a half-space is analyzed using the theory of linear piezoelectricity. Both out-of-plane mechanical and in-plane electrical loads are applied to the piezoelectric laminate. By the use of courier transforms, the mixed boundary value problem is reduced to a singular integral equation which is solved numerically to determine the stress intensity factors. Numerical analyses for various material combinations are performed and the results are discussed.

$T_{b}$-$N_{HI}$ CORRELATION IN THE GALACTIC PLANE

  • Kim, Yong-Gi
    • Journal of Astronomy and Space Sciences
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    • v.17 no.1
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    • pp.33-38
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    • 2000
  • Synchrotron emission at 408 MHz and HI column density have been used to find an evidence for the relationship between the Galactic magnetic field and the gas density. The observational data of the brightness temperature and HI column density, $T_b(408)\;and \;N_{HI}$, near the galactic plane between galactic longitudes $l=62^{circ}\;and\;l=250^{\circ}$ show a clear linear correlation of $T_b(408)=A(l,b)+B\;N_{HI}$, where A(l, b)is a background and forground radiation at the galactic coordinate. We found $(1.4{pm}0.3)10^{-21}$ for the slope B, which describes the strength of the syncrotron radiation from the HI cloud, and agrees with the value for the MIlky Way obtained by Beuermann et al. (1985). We conclude therefore that a well defined nonthermal corelates with the HI column density originating from this HI cloud.

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3D SCENE EDITING BY RAY-SPACE PROCESSING

  • Lv, Lei;Yendo, Tomohiro;Tanimoto, Masayuki;Fujii, Toshiaki
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2009.01a
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    • pp.732-736
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    • 2009
  • In this paper we focus on EPI (Epipolar-Plane Image), the horizontal cross section of Ray-Space, and we propose a novel method that chooses objects we want and edits scenes by using multi-view images. On the EPI acquired by camera arrays uniformly distributed along a line, all the objects are represented as straight lines, and the slope of straight lines are decided by the distance between objects and camera plane. Detecting a straight line of a specific slope and removing it mean that an object in a specific depth has been detected and removed. So we propose a scheme to make a layer of a specific slope compete with other layers instead of extracting layers sequentially from front to back. This enables an effective removal of obstacles, object manipulation and a clearer 3D scene with what we want to see will be made.

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Simultaneous Water and class I Methanol maser Survey of Shocker H2 Emitting regions

  • Lim, Wang-Gi;Lyo, A-Ran;Kim, Kee-Tae
    • The Bulletin of The Korean Astronomical Society
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    • v.36 no.2
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    • pp.118-118
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    • 2011
  • We executed a simultaneous survey of 22 GHz water maser and 44 GHz methanol maser toward 290 shocked $H_2$ emitting regions, which were identified from the galactic plane survey at $H_2$ 2.122 micrometer (UKIRT Widefield Infrared Survey for $H_2$; UWISH2). The primary goal of this observation is to characterize the H2 emission sources whether they are sincerely due to the outflows of young stellar objects or other shocked emission from older/evolved objects. We discovered 15 water maser sources and 15 methanol maser sources which provide the detection rate of around 5 percents. Most of detected sources have IRAS sources, infrared dark clouds, and/or submilimeter sources in the beam size of KVN single dish. In this poster, we will present the detailed results of our survey observation and discuss about the star formation rate in the galactic plane.

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Catalog of the Paα-emitting Sources observed in the Carina Region

  • Kim, Il-Joong;Pyo, Jeonghyun;Jeong, Woong-Seob
    • The Bulletin of The Korean Astronomical Society
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    • v.46 no.2
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    • pp.66.2-66.2
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    • 2021
  • We list up the Paα-emitting sources observed in the Carina Region (l = 276°-296°) using the MIRIS Paα Galactic Plane Survey data. A total of 201 sources are cataloged. Out of them, 118 sources are coincident with those in the WISE H II region catalog. 52 H II region candidates are newly confirmed as definite H II regions by detecting the Paα recombination lines. For the remaining 83 sources, we search the corresponding objects in the SIMBAD database. 26 point-like sources are associated with planetary nebulae or emission-line stars (such as Wolf-Rayet and Blue supergiant stars). Also, we carry out aperture photometry to measure Paα fluxes for the sources that show circular features without overlapping with other bright sources. For the whole Galactic Plane, the complete Paα-emitting source catalog is in progress.

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Healing Environment at the General Hospital Lobby Space -By comparison of the lobby plan type- (종합병원 로비공간의 치유환경에 관한 연구 -로비 평면형태의 비교를 중심으로-)

  • Lee, Yu-Jung;Oh, Joon-Gul
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.5
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    • pp.89-97
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    • 2018
  • In the past, hospitals were planned with a minimum of public space for the sole purpose of treatment. On the other hand, modern hospitals have more public space as the importance of the healing environment increases and are planned taking into consideration the patients, guardians, and medical staff. In addition, the lobby shape is developed from a HALL type and planned as a STREET type or CONCOURSE type, increasing the public area. Unlike past hospitals, which were used as reception, waiting, and procedure spaces, modern hospitals are used as commercial, hobby, and cultural space. The purpose of the study was to evaluate the healing environment of the hospital lobby based on the shape of the plane surface by deducting the elements of general hospitals' healing environment from preceding studies as a framework. The hospital lobby is an important place where many actions occur. Therefore, 3 types of cases were evaluated based on the plane form. As a result of the study, the STREET type showed a better healing environment than the HALL type, but the accessibility, roof garden, and resting place showed similar results. Because the case was based on a large general hospital, which had sufficient planned space, the factor has little to do with the style of the lobby. Among the STREET types, the linear atrium showed a better result in terms of the sense of space and inflow effect of natural lighting than the four-sided atrium because the linear atrium has large open volume ratio. When the lobby plane is the HALL type, a cross section of the courtyard had a large open volume ratio. Therefore, the shape of the cross section is as important as the plane form of the lobby.

A Study on QTG(Qualification Test Guide) Generation for a Flight Training Device to be Qualifiable at FAA Level 5 (X-Plane 기반 비행훈련장치의 FAA Level 5 FTD(Flight Training Device) 인증을 위한 QTG(Qualification Test Guide) 생성방법 연구)

  • Kim, Il-Woo;Park, TaeJun;Yoon, SukJun
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.44 no.12
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    • pp.1035-1042
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    • 2016
  • By using commercial flight simulation game engine, X-Plane, we have studied QTG(Qualification Test Guide) generation that can satisfy FTD level 5. Flight model is SR-20 of Cirrus. In list of QTG, There are some items to measure control forces. therefore, we have installed CLS(Control Loading System) to flight control devices in order to make it possible to measure control forces. We made Autopilot function externally to make flight model in trim conditions because X-Plane don't provide internal trim routine function. In addition to develop an algorithm, it can automatically perform the test. To avoid the inconvenience to control as it was to be carried out in same conditions. In case of FTD level 5, it is possible to use alternative data sources not only real flight data. By using these alternative data sources, all test results satisfy a scope given by CFR Part 60.

An experimental study on the load transfer machanism of shallow 2-arch tunnel excavation sequence with vertical discontinuity planes in sandy ground (연직 불연속면이 존재하는 얕은 심도의 사질토 지반에서 2-arch 터널 단계별 굴착에 따른 하중전이에 관한 실험적연구)

  • Oh, Bum-Jin;Lee, Sang-Duk
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.13 no.3
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    • pp.215-231
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    • 2011
  • In this study, the behavior of a shallow 2-arch tunnel during the excavation in the sandy ground containing vertical discontinuity plane was experimentally studied. Load transfer mechanism in the pillar caused by a 2-arch tunnel excavation was observed. The position of the vertical discontinuity plane was varied. Model tests were carried out in the normal construction sequence of 2-arch tunnel. Test results-showed that the load transfer caused by the 2-arch tunnel excavation was concentrated in the discontinuity plane, and was cut by the discontinuity plane, so no load transfer took place above the discontinuity plane. It was also shown that the effect of adjacent tunnel excavation on the pillar load and the ground deformation was greater when excavating the upper half-face of the main tunnel, more than when excavating the lower half-face.

Load-transfer mechanism in the ground with discontinuity planes during tunnel excavation (불연속면이 존재하는 지반에서 터널굴착에 의한 하중전이)

  • Lee, Sang-Duk;Byun, Gwang-Wook;Yoo, Kun-Sun
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.4 no.1
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    • pp.71-78
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    • 2002
  • In this study, the influence of the presence of discontinuity planes on the load transfer mechanism and the pattern of loosening zone was studied based on the laboratory test. The trap-door and the reaction plates are installed as the bottom plane of the model box. The vertical discontinuity plane is installed in the dry sand. Various overburden heights and locations of discontinuity planes are applied as major factors in this study. The results show that at higher overburden heights over about 1.5 times the excavation width, the ratio of the transferred stress to the insitu stress converges to a certain value even if the overburden height increases further. The results also show that the discontinuity plane gives relatively larger influence on the load transfer mechanism, that produces the unsymmetrical load concentration, when the discontinuity plane locates within the tunnel width. When the discontinuity plane locates outside the tunnel width, the unsymmetrical load concentration is reduced considerably.

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