• Title/Summary/Keyword: Intermediate space

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H$\gamma$LINE SPECTRUM OF INTERMEDIATE POLARS

  • Kim, Yong-Gi
    • Journal of Astronomy and Space Sciences
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    • v.15 no.1
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    • pp.59-64
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    • 1998
  • Kim & Beuermann (1995, 1996)have developed a model for the propagation of X-rays from the accreting white dwarfthrough the infalling material and the re-emission of the energy deposited by photo-absorption in the optical (and UV) spectral range. By using this model, we calculate the profiles of the $H_{\gamma}$ emission-line spectrum of intermediate polars. Photoabsorption of X-ray by the infalling material is the dominant process in forming the observed energy-dependent rotational modulation of the X-ray flux. X-ray and optical modulations are sensitive to model parameters in different ways. In principle, these dependencies allow us to obtain improved insight into the accretion geometry of the intermediate polars. We present results of our calculations and compare them with the $H{\beta}$ line spectrum(Kim & Beuermann 1996).

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A MAGNETOHYDRODYNAMIC MODEL FOCUSED ON THE CONFIGURATION OF MAGNETIC FIELD RESPONSIBLE FOR A SOLAR PENUMBRAL MICROJET

  • Magara, Tetsuya
    • The Bulletin of The Korean Astronomical Society
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    • v.35 no.2
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    • pp.49.2-49.2
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    • 2010
  • In order to understand the configuration of magnetic field producing a solar penumbral microjet that was recently discovered by Hinode, we performed a magnetohydrodynamic simulation reproducing a dynamic process of how that configuration is formed in a modeled solar penumbral region. A horizontal magnetic flux tube representing a penumbral filament is placed in a stratified atmosphere containing the background magnetic field that is directed in a relatively vertical direction. Between the flux tube and the background field there forms the intermediate region in which the magnetic field has a transitional configuration, and the simulation shows that in the intermediate region magnetic reconnection occurs to produce a clear jet- like structure as suggested by observations. The result that a continuous distribution of magnetic field in three-dimensional space gives birth to the intermediate region producing a jet presents a new view about the mechanism of a penumbral microjet, compared to a simplistic view that two field lines, one of which represents a penumbral filament and the other the background field, interact together to produce a jet. We also discuss the role of the intermediate region in protecting the structure of a penumbral filament subject to microjets.

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Determination of the Minimum Number of Intermediate Points for the Robot Manipulator Cartesian Stright Motion (로보트 매니퓰레이터의 카르테시안 직선운동을 위한 경로집의 최소화)

  • 오세현;전홍태
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.25 no.2
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    • pp.144-151
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    • 1988
  • Between any two points in the Cartesian space, the straight motion has many distinct advantages in path/trajectory plannings, specially in a crowded workspace. But to achieve this motion is a nontrivial task. One standard way to approximate this motion is to plae enough intermediate points along the desired path and linearly interpolate two adjacent intermediate points in the joint space. In this approach, however, the determination of the minimum number of intermediate points is very important from several aspects. A scheme that can effectively accomplish this purpose is established in this paper. This scheme is based on several search methods. The results are demonstrated using the PUMA 560 series manipulator.

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Path Space Approach for Planning 2D Shortest Path Based on Elliptic Workspace Geometry Mapping

  • Namgung, Ihn
    • Journal of Mechanical Science and Technology
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    • v.18 no.1
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    • pp.92-105
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    • 2004
  • A new algorithm for planning a collision-free path based on algebraic curve is developed and the concept of collision-free Path Space (PS) is introduced. This paper presents a Geometry Mapping (GM) based on two straight curves in which the intermediate connection point is organized in elliptic locus ($\delta$, $\theta$). The GM produces two-dimensional PS that is used to create the shortest collision-free path. The elliptic locus of intermediate connection point has a special property in that the total distance between the focus points through a point on ellipse is the same regardless of the location of the intermediate connection point on the ellipse. Since the radial distance, a, represents the total length of the path, the collision-free path can be found as the GM proceeds from $\delta$=0 (the direct path) to $\delta$=$\delta$$\_$max/(the longest path) resulting in the minimum time search. The GM of elliptic workspace (EWS) requires calculation of interference in circumferential direction only. The procedure for GM includes categorization of obstacles to .educe necessary calculation. A GM based on rectangular workspace (RWS) using Cartesian coordinate is also considered to show yet another possible GM. The transformations of PS among Circular Workspace Geometry Mapping (CWS GM) , Elliptic Workspace Geometry Mapping (EWS GM) , and Rectangular Workspace Geometry Mapping (RWS GM), are also considered. The simulations for the EWS GM on various computer systems are carried out to measure performance of algorithm and the results are presented.

Intermediate Polar 별의 X-선 재방출

  • 김용기
    • Bulletin of the Korean Space Science Society
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    • 1992.10a
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    • pp.20-20
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    • 1992
  • 격변 변광성의 일종인 DQ Her형 별(Intermediate Polar Star; IP)이 자기장에서 방출하는 가시광선은 자전주기에 따라 그 강도가 변한다. 이러한 쌍성계에서 백색 왜성인 주성의 주번에 자기력 선을 따라 정도의 물질이 주계열성인 반성으로부터 accretion 된다. 이 물질은 주성 표면에서 충격파로 생긴 X-선원에 의해 reemission 되는 데, 이런 현상적인 모델을 만들어 관측적으로 나타나는 자전주기에 따른 가시광선의 강도 변화를 설명하였다. 이런 결과가 IP 에서 방출되는 가시광선 관측의 분석과 이런 종류의 쌍성계가 가지는 궤도기울기, accretion rate, 공전축에 대한 자전축의 기울기, interaction radius 등의 물리적 상수를 결정하는 데 응용될 수 있음을 보이려고 한다.

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MAGNETOSPHERIC STRUCTURE OF THE INTERMEDIATE POLAR

  • Kim, Yong-Gi
    • Journal of Astronomy and Space Sciences
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    • v.11 no.1
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    • pp.1-12
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    • 1994
  • The structure of the magnetic funnel element in the intermediate polar is considered in terms of an important site for the X-ray absorption and the reemission of the X-ray as the optical light. In this paper the column density and the optical depth vary with the filling factor, which is introduced to characterize the structure of matter in the magnetic funnel element. The results of the energy dependence of the X-ray spectrum and the modulation depth of the X-ray light curve are discussed.

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PHOTOABSORPTION OF X-RAYS IN THE MAGNETIC COMPACT STAR

  • Kim, Yong-Gi
    • Journal of Astronomy and Space Sciences
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    • v.9 no.2
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    • pp.171-182
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    • 1992
  • Radiation due to accretion from an accretion disc around the intermediate polars and photoabsorption of this radiation in the accretion funnel have been taken into account as a phenomenological model to study the physics of the magnetic funnel in the magnetic compact star. The first results show that such a model scenario can be used to estimate some parameters in these systems. Some constraints of this model regarding to the observational data of one intermediate polar, EX Hya, are also discussed.

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A Study on the Facade in Depth of Architecture - Focusing on works of Paul $C\acute{e}zanne$ - (건축 입면의 깊이에 관한 연구 - Paul $C\acute{e}zanne$의 회화를 중심으로 -)

  • Yook, Ok-Soo
    • Journal of architectural history
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    • v.15 no.4
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    • pp.57-73
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    • 2006
  • To begin with the purpose of protecting human life from the exterior in the prehistoric age, architecture was nothing but a shelter without any relation between the exterior and the intoner. But, today, with the community developed, architecture can not be resisted with her own function and have to change of the reciprocal one. Different with the oriental architecture, we can see, western architecture has developed in the stream of the form. The main idea of the space in terms of the relation, above all, is mostly concerned with relation between the exterior and the interior like between the architecture and the city. So the role of the facade in depth is the intermediation which consist to the relation in the exterior and interior of architecture. Considering a relation between two elements; the exterior and the interior, we can be inspired in the case of paintings, especially in the works of the Paul $C\acute{e}zanne$. $C\acute{e}zanne$ originally show the depth of space by different disposition of three parts : the background, the objects and intermediate space between the former. For instance, different with the other painters who put the background rear in the canvas and objects in the front of the background, $C\acute{e}zanne$ took the background and objects a same value and assure a depth in space by virtue of the intermediate space. Finally, by putting the background in forward of layer in the canvas and objects situated behind the background, the depth of the space can be occurred. Same as the idea of $C\acute{e}zanne$, Giuseppe Terragni and jean Nouvelle in architecture also intensify their effects through the activation of intermediate space between the interior facade and exterior frame. Not limited in the relation with the architecture and the city, space in relation gives us a higher quality of architectural promenade in depth.

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