• Title/Summary/Keyword: harmonic behavior

Search Result 200, Processing Time 0.027 seconds

ASYMPTOTIC BEHAVIOR OF A-HARMONIC FUNCTIONS AND p-EXTREMAL LENGTH

  • Kim, Seok-Woo;Lee, Sang-Moon;Lee, Yong-Hah
    • Bulletin of the Korean Mathematical Society
    • /
    • v.47 no.2
    • /
    • pp.423-432
    • /
    • 2010
  • We describe the asymptotic behavior of functions of the Royden p-algebra in terms of p-extremal length. We also prove that each bounded $\cal{A}$-harmonic function with finite energy on a complete Riemannian manifold is uniquely determined by the behavior of the function along p-almost every curve.

Effect of Core-Shell Structure on Compaction Behavior of Harmonic Powder (Core-shell 구조를 지니는 하모닉 분말의 성형거동 분석)

  • Joo, Soo-Hyun;Park, Hyo Wook;Kang, Soo Young;Lee, Eon Sik;Kang, Hee-Soo;Kim, Hyong Seop
    • Journal of Powder Materials
    • /
    • v.22 no.2
    • /
    • pp.105-110
    • /
    • 2015
  • In this study, effect of core-shell structure on compaction behavior of harmonic powder is investigated. Harmonic powders are made by electroless plating method on Fe powders. Softer Cu shell encloses harder Fe core, and the average size of Fe core and thickness of Cu shell are $34.3{\mu}m$ and $3.2{\mu}m$, respectively. The powder compaction procedure is processed with pressure of 600 MPa in a cylindrical die. Due to the low strength of Cu shell regions, the harmonic powders show better densification behavior compared with pure Fe powders. Finite element method (FEM) is performed to understand the roll of core-shell structure. Based on stress and strain distributions of FEM results, it is concluded that the early stage of powder compaction of harmonic powders mainly occurs at the shell region. FEM results also well predict porosity of compacted materials.

ON THE BEHAVIOR OF L2 HARMONIC FORMS ON COMPLETE MANIFOLDS AT INFINITY AND ITS APPLICATIONS

  • Yun, Gabjin
    • Korean Journal of Mathematics
    • /
    • v.6 no.2
    • /
    • pp.205-212
    • /
    • 1998
  • We investigate the behavior of $L^2$ harmonic one forms on complete manifolds and as an application, we show the space of $L^2$harmonic one forms on a complete Riemannian manifold of nonnegative Ricci curvature outside a compact set with bounded $n/2$-norm of Ricci curvature satisfying the Sobolev inequality is finite dimensional.

  • PDF

ASYMPTOTIC BEHAVIOR OF HARMONIC MAPS AND EXPONENTIALLY HARMONIC FUNCTIONS

  • Chi, Dong-Pyo;Choi, Gun-Don;Chang, Jeong-Wook
    • Journal of the Korean Mathematical Society
    • /
    • v.39 no.5
    • /
    • pp.731-743
    • /
    • 2002
  • Let M be a Riemannian manifold with asymptotically non-negative curvature. We study the asymptotic behavior of the energy densities of a harmonic map and an exponentially harmonic function on M. We prove that the energy density of a bounded harmonic map vanishes at infinity when the target is a Cartan-Hadamard manifold. Also we prove that the energy density of a bounded exponentially harmonic function vanishes at infinity.

POLYNOMIAL GROWTH HARMONIC MAPS ON COMPLETE RIEMANNIAN MANIFOLDS

  • Lee, Yong-Hah
    • Bulletin of the Korean Mathematical Society
    • /
    • v.41 no.3
    • /
    • pp.521-540
    • /
    • 2004
  • In this paper, we give a sharp estimate on the cardinality of the set generating the convex hull containing the image of harmonic maps with polynomial growth rate on a certain class of manifolds into a Cartan-Hadamard manifold with sectional curvature bounded by two negative constants. We also describe the asymptotic behavior of harmonic maps on a complete Riemannian manifold into a regular ball in terms of massive subsets, in the case when the space of bounded harmonic functions on the manifold is finite dimensional.

GENERAL MIXED HARMONIC VARIATIONAL INEQUALITIES

  • Jong Kyu Kim;Avinash Lakhnotra;Tirth Ram
    • Nonlinear Functional Analysis and Applications
    • /
    • v.29 no.2
    • /
    • pp.517-526
    • /
    • 2024
  • In this paper, some iterative methods are used to discuss the behavior of general mixed-harmonic variational inequalities. We employ the auxiliary principle technique and g-strongly harmonic monotonicity of the operator to obtain results on the existence of solutions to a generalized class of mixed harmonic variational inequality.

Performance Evaluation of the Harmonic Parameters for High Impedance Fault Detection in Distribution System (배전계통의 고 임피던스 고장 검출 고조파 변수 성능 평가)

  • Oh, Yong-Taek;Kim, C.J.
    • Proceedings of the KIEE Conference
    • /
    • 1997.07c
    • /
    • pp.883-885
    • /
    • 1997
  • High impedance fault(HIF) is random in its behavior even in a similar environment. The detection of Ire HIF has focused on the development of algorithms based on harmonic, parameters of the arc currents. However, a fact that proper selection of the harmonic parameters, rather than algorithm selection, is more important is shown in this paper by applying three different performance evaluation methods on two HIF detection algorithms using eight harmonic parameters.

  • PDF

Phased Array Behavior of the Coupling of the Millimeter Wave Second Harmonic Oscillator (밀리미터파 대역 제2고조파 발진기 결합계의 위상차 배열 동작)

  • Choi, Young-Kyu;Kim, Gi-Rae
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.64 no.3
    • /
    • pp.438-444
    • /
    • 2015
  • A new approach to the active phased arrays for the second harmonic generation is presented. Phase variation between the second harmonic oscillators by the mutual synchronization is analyzed theoretically. In this coupling, the active antenna consists of the FET oscillator which plays two roles in fundamental oscillation and frequency multiplying, and the patch antenna resonated at the second harmonic frequency. The radiated second harmonic wave was scanned by varying the free-running oscillation frequencies of the active antennas. In the experiment using the 2-elements array and the 4-elements array, the radiated beam of the second harmonic wave was scanned more widely compared with the case of the fundamental wave radiation.

Improvement of Dynamic Behavior of Shunt Active Power Filter Using Fuzzy Instantaneous Power Theory

  • Eskandarian, Nasser;Beromi, Yousef Alinejad;Farhangi, Shahrokh
    • Journal of Power Electronics
    • /
    • v.14 no.6
    • /
    • pp.1303-1313
    • /
    • 2014
  • Dynamic behavior of the harmonic detection part of an active power filter (APF) has an essential role in filter compensation performances during transient conditions. Instantaneous power (p-q) theory is extensively used to design harmonic detectors for active filters. Large overshoot of p-q theory method deteriorates filter response at a large and rapid load change. In this study the harmonic estimation of an APF during transient conditions for balanced three-phase nonlinear loads is conducted. A novel fuzzy instantaneous power (FIP) theory is proposed to improve conventional p-q theory dynamic performances during transient conditions to adapt automatically to any random and rapid nonlinear load change. Adding fuzzy rules in p-q theory improves the decomposition of the alternating current components of active and reactive power signals and develops correct reference during rapid and random current variation. Modifying p-q theory internal high-pass filter performance using fuzzy rules without any drawback is a prospect. In the simulated system using MATLAB/SIMULINK, the shunt active filter is connected to a rapidly time-varying nonlinear load. The harmonic detection parts of the shunt active filter are developed for FIP theory-based and p-q theory-based algorithms. The harmonic detector hardware is also developed using the TMS320F28335 digital signal processor and connected to a laboratory nonlinear load. The software is developed for FIP theory-based and p-q theory-based algorithms. The simulation and experimental tests results verify the ability of the new technique in harmonic detection of rapid changing nonlinear loads.

Analysis of Magnetic Field Behavior and Iron Loss in Stator Core of Permanent Magnet Type Motor (영구자석형 모터의 고정자 철심에서 자계의 거동 및 철손 분석)

  • Ha Kyung-Ho;Cha Sang-Yoon;Kim Jae-Kwan;Hong Jung-Pyo
    • The Transactions of the Korean Institute of Electrical Engineers B
    • /
    • v.55 no.2
    • /
    • pp.76-82
    • /
    • 2006
  • This paper investigates the magnetic field behavior and its iron losses in the stator core using electrical steels. The analysis model is a brushless motor with the permanent magnet. The elliptical rotating and alternating flux distributions with non-sinusoidal waveform are obtained by Finite Element Method and then their harmonic components are extracted. Based on these results, the local iron losses in the stator core caused by the harmonic flux are calculated. And then this paper explains the relation between flux waveform and iron loss produced in each part of the stator core. Furthermore, the iron loss at no load condition is measured and compared with the analysis results.