• 제목/요약/키워드: Planar.

검색결과 3,651건 처리시간 0.034초

복사 열손실을 받는 셀모양 대향류 확산화염의 선형 안정성 해석 (Linear Stability Analysis of Cellular Counterflow Diffusion Flames with Radiation Heat Loss)

  • 이수룡
    • 한국연소학회지
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    • 제18권2호
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    • pp.42-50
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    • 2013
  • Linear stability analysis of radiating counterflow diffusion flames is numerically conducted to examine the instability characteristics of cellular patterns. Lewis number is assumed to be 0.5 to consider diffusional-thermal instability. Near kinetic limit extinction regime, growth rates of disturbances always have real eigen-values and neutral stability condition of planar disturbances perfectly falls into quasi-steady extinction. Cellular instability of disturbance with transverse direction occurs just before steady extinction. However, near radiative limit extinction regime, the eigenvalues are complex and pulsating instability of planar disturbances appears prior to steady extinction. Cellular instability occurs before the onset of planar pulsating instability, which means the extension of flammability.

6.6kV 회전기 고정자 권선에서 부분방전 진단을 위한 평판 안테나 센서 설계 (The Design of a Planar Antenna Sensor for Partial Discharge diagnosis in 6.6kV Rotary Machine Stator Windings)

  • 임광진;키아우소륀;신동훈;박노준;박대희
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2007년도 Techno-Fair 및 추계학술대회 논문집 전기물성,응용부문
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    • pp.222-223
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    • 2007
  • In 6.6kV Rotary Machine Stator Windings, Corona Discharge, Discharge at Conductor Surface, Slot Discharge and Endwinding Discharge is happended by electronic degradation. Also, if Partial Discharge cause in inner-part of Rotary Machine Stator Windings, it will be happended voltage and current pulse. In case of discharge spark, RF electromagnetic wave, which tranmits at discharge position, can happen. To detect this kind of RF electromagnetic wave efficiently, we have designed Planar Antenna Sensor with the CST MWS simulation program. Also we have confined the application possibility, which can analize the partial discharge in Rotary Machine Stator Windings. In the Future, sample of planar antenna sensor will be able to compare with the data of simulation by CST MWS program.

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THE LINEAR 2-ARBORICITY OF PLANAR GRAPHS WITHOUT ADJACENT SHORT CYCLES

  • Chen, Hong-Yu;Tan, Xiang;Wu, Jian-Liang
    • 대한수학회보
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    • 제49권1호
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    • pp.145-154
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    • 2012
  • Let G be a planar graph with maximum degree $\Delta$. The linear 2-arboricity $la_2$(G) of G is the least integer k such that G can be partitioned into k edge-disjoint forests, whose component trees are paths of length at most 2. In this paper, we prove that (1) $la_2(G){\leq}{\lceil}\frac{\Delta}{2}\rceil+8$ if G has no adjacent 3-cycles; (2) $la_2(G){\leq}{\lceil}\frac{\Delta}{2}\rceil+10$ if G has no adjacent 4-cycles; (3) $la_2(G){\leq}{\lceil}\frac{\Delta}{2}\rceil+6$ if any 3-cycle is not adjacent to a 4-cycle of G.

Mobility analysis of Planar Mobile Robots and The Rough-Terrain Mobile Robot via The Screw

  • Kim, Whee-Kuk;Yi, Byung-Ju;Lee, Seung-Eun
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2001년도 ICCAS
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    • pp.59.3-59
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    • 2001
  • In this paper, the method of analyzing mobility of the mechanisms is suggested. The method based on the joint screws provides accurate values of mobility of the mechanisms even with the lack of geometric generality. To show its validity, the method is applied to finding mobilities of planar mobile robots and a rough-terrain mobile robot, Mars Rover. To do so, simplified joint model for each of four different typical wheels of the mobile robots are described including friction velocities, firstly. Then, mobility analyses of planar mobile robots and the Mars Rover mobile robot for navigation on the rocky road on Mars are performed. It is confirmed that the obtained results in this study coincide with the previous ones which ...

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Kinematic Displacement Theory of Planar Structures

  • Tayyar, Gokhan Tansel;Bayraktarkatal, Ertekin
    • International Journal of Ocean System Engineering
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    • 제2권2호
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    • pp.63-70
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    • 2012
  • This paper presents a new curvature based kinematic displacement theory and a numerical method to calculate the planar displacement of structures from a geometrical viewpoint. The theory provides an opportunity to satisfy the kinematic equilibrium of a planar structure using a progressive numerical approach, in which the cross sections are assumed to remain plane, and the deflection curve was evaluated geometrically using the curvature values despite being solved using differential equations. The deflection curve is parameterized with the arc-length, and was taken as an assembly of the chains of circular arcs. Fast and accurate solutions of most complex deflections can be obtained with few inputs.

Calculation of the Dipole Moments for Transition Metal Complexes by the Valence Bond Method (Ⅱ). Calculation of the Dipole Moments for Square Planar and Tetrahedral [M (Ⅱ) $N_2Se_2$] Type Complexes [M (Ⅱ) = Co (Ⅱ), Ni (Ⅱ) or Zn (Ⅱ)]

  • Ahn, Sang-Woon;Park, Eu-Suh;Lee, Kee-Hag
    • Bulletin of the Korean Chemical Society
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    • 제2권3호
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    • pp.79-82
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    • 1981
  • A calculation method of the dipole moments for square planar and tetrahedral complexes by the valence bond method has been developed and an example calculation was carried out choosing the square planar and tetrahedral $[M(Ⅱ)N_2Se_2]$ type complexes. The calculated values of the dipole moments by the valence bond method are higher than those of the approximate orbital method. We found that we may predict the geometric structure of the transition metal complexes comparing the calculated values of the dipole moments with the experimental values. A new method for definition of C' parameter has also developed on the basis of extended Huckel theory.

Theory of Scalar Wave Scattering by a Sphere and a Planar Substrate

  • Park, Byong Chon;Kim, Jin Seung
    • Journal of the Korean Physical Society
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    • 제73권10호
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    • pp.1512-1518
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    • 2018
  • The problem of scalar wave scattering by a sphere on or near a planar substrate is analytically solved. The solution is a set of wave functions coming in the form of infinite series of spherical and plane waves. In air, the incident plane wave is either scattered by the sphere or reflected from the substrate. A part of these scattered or reflected waves propagate to the other object where it is reflected and scattered again. Such processes of scattering and reflection repeat in turn indefinitely to generate multiply scattered waves, which are represented in the corresponding terms in the infinite series. The term in the series can be arranged in a recognizable manner to explicitly reveal the involved process and the multiplicity of scattering.

The Reaction of 6,7-Dichloro-5,8-quinoxalinedione with Aromatic and Aliphatic Dinucleophiles and Molecular Modeling Study of Their Intercalation Complexes

  • 유희원;서명은;신계중;박상우
    • Bulletin of the Korean Chemical Society
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    • 제18권5호
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    • pp.484-488
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    • 1997
  • The angular and planar heterocyclic compounds containing nitrogen, sulfur and oxygen were synthesized by reaction of 6,7-dichloro-5,8-quinoxalinedione with aromatic and aliphatic dinucleophiles. Nucleophilic reactivity was somewhat different between 2,3-dichloro-1,4-naphthoquinone and 6,7-dichloro-5,8-quinolinedione with dinucleophiles. The distribution of electron in heterocycle appeared to contribute to this difference. The intercalation comple of planar heterocyclic compound between GC/GC base pairs showed the optimum intercalation but the intercalation of angular heterocyclic compound was not good. Thus, the planar compound was expected to have antitumor activity.

Fabrication of Planar Type Inductors Using FeTaN Magnetic Thin Films

  • Kim, Chung-Sik;Seok Bae;Jeong, Jong-Han;Nam, Seoung-Eui;Kim, Hyoung-June
    • Journal of Magnetics
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    • 제6권2호
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    • pp.73-76
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    • 2001
  • A double rectangular spiral type inductor has been fabricated by using FeTaN films. The inductor is composed of internal coils sandwiched by magnetic layers. Characteristics of inductor performance are investigated with an emphasis on planarization of magnetic films. In the absence of the planarization process, the grating topology of the upper magnetic films over the coil arrays degrades the soft magnetic properties and the inductor performance. It also induces a longitudinal magnetic anisotropy with the easy axis aligned to the magnetic flux direction. This alignment prevents the upper magnetic films from contributing to the total induction. Glass bonding is a viable method for achieving a completely planar inductor structure. The planar inductor with glass bonding shows excellent performance: inductance of 1.1 $\mu H$, Q factor of 7 (at 5 MHz), and the current capability up to 100 mA.

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Metallic Crack Detections by Planar Inductive Coil Sensor Under AC and DC Magnetic Fields

  • Lee, Joon-Sik;Nam, Baek-Il;Kim, Ki-Hyeon
    • Journal of Magnetics
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    • 제17권3호
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    • pp.210-213
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    • 2012
  • To detect the surface and the opposite side cracks on iron specimen under AC and DC magnetic fields, the planar inductive coil sensors were employed. When the induced signals were measured, the planar inductive coil sensor and the magnetic field source were lifted off about 2 mm from the top surface of the specimen. AC magnetic fields and DC magnetic fields were applied to the specimens by single straight Cu coil and NdFeB permanent magnet, respectively. The detected signals at crack positions were good coincidence with those of the simulation results.