• Title, Summary, Keyword: End effects

Search Result 3,072, Processing Time 0.073 seconds

End Effects of Thin-Walled Beams with General Quadrilateral Cross Sections (일반 사각 단면 형상을 갖는 박판보의 끝단효과에 관한 연구)

  • Kim, Jin-Hong;Kim, Yun-Yeong
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.24 no.9
    • /
    • pp.2191-2201
    • /
    • 2000
  • End effects due to sectional deformations of thin-walled beams with closed cross section are analysed by a one-dimensional theory. In particular, end effects associated with warping (out of plane m otion) and distortion (in plane motion) are investigated. The exact solutions as a vector form are newly derived to reveal slowly-decaying nature of the end effects in a thin-walled beam loaded by a couple. Several examples of thin-walled beams under various loading conditions indicate that the local end effect zone due to warping and distortion is approximately ten times the typical beam width.

End-to-End Analysis to Audit Information Systems for Telecommunication Industry (통신산업의 정보시스템 감사를 위한 단대단 분석)

  • Lee, Joong Hee;Lee, Sangwon
    • Proceedings of the Korean Society of Computer Information Conference
    • /
    • /
    • pp.325-327
    • /
    • 2013
  • Although, there are so much information for telecommunication companies to manipulate and handle. there are still many side-effects in the field of completeness while transmitting information among information systems. Especially, works related to End-to-End Reconciliation bring about side-effects. In this research, we establish a proposed model for end-to-end analysis. After an experiment in a business company, we analyze its experimental results.

  • PDF

Influences of Viscous Losses and End Effects on Liquid Metal Flow in Electromagnetic Pumps

  • Kim, Hee-Reyoung;Seo, Joon-Ho;Hong, Sang-Hee;Suwon Cho;Nam, Ho-Yun;Man Cho
    • Proceedings of the Korean Nuclear Society Conference
    • /
    • /
    • pp.233-240
    • /
    • 1996
  • Analyses of the viscous and end effects on electromagnetic (EM) pumps of annular linear induction type for the sodium coolant circulation in Liquid Metal Fast Breeder Reactors have been carried out based on the MHD laminar flow analysis and the electromagnetic field theory. A one-dimensional MHD analysis for the liquid metal flowing through an annular channel has been performed on the basis of a simplified model of equivalent current sheets instead of three-phase currents in the discrete primary windings. The calculations show that the developed pressure difference resulted from electromagnetic and viscous forces in the liquid metal is expressed in terms of the slip, and that the viscous loss effects are negligible compared with electromagnetic driving forces except in the low-slip region where the pumps operate with very high flow velocities comparable with the synchronous velocity of the electromagnetic fields, which is not applicable to the practical EM pumps. A two-dimensional electromagnetic field analysis based on an equivalent current sheet model has found the vector potentials in closed form by means of the Fourier transform method. The resultant magnetic fields and driving forces exerted on the liquid metal reveal that the end effects due to finiteness of the pump length are formidable. In addition, a two-dimensional numerical analysis for vector potentials has been performed by the SOR iterative method on a realistic EM pump model with discretely-distributed currents in the primary windings. The numerical computations for the distributions of magnetic fields and developed pressure differences along the pump axial length also show considerable end effects at both inlet and outlet ends, especially at high flow velocities. Calculations of each magnetic force contribution indicate that the end effects are originated from the magnetic force caused by the induced current ( u x B ) generated by the liquid metal movement across the magnetic field rather than the one (E) produced by externally applied magnetic fields by three-phase winding currents. It is concluded that since the influences of the end effects in addition to viscous losses are extensive particularly in high-velocity operations of the EM pumps, it is necessary to find ways to suppress them, such as proper selection of the pump parameters and compensation of the end effects.

  • PDF

The Characteristic Analysis of Vector Control in a Linear Induction Motor Considering Static and Dynamic End Effects (정적 및 동적 단부효과를 고려한 선형 유도 전동기의 벡터제어 특성해석)

  • Kim, Dae-Gyeong;Gwon, Byeong-Il;U, Gyeong-Il
    • The Transactions of the Korean Institute of Electrical Engineers B
    • /
    • v.51 no.8
    • /
    • pp.413-424
    • /
    • 2002
  • Recently, in the linear motion system, high performances are required In dynamic characteristics. Vector control method is capable of instantaneous thrust control can meet these high performance requirements. Linear induction motor(LIM) have static and dynamic end effects due to its finite core length, so that per-phase impedances are asymmetric and an air gap flux distribution is distorted. These points of the d-q axis equivalent circuit model considering both end effects is more complicated. This paper proposes the d-q axis equivalent circuit and the vector control method considering both static and dynamic end effects of the LIM. As a result, it is shown that the results of the equivalent circuit method(ECM) have a good agreement with those of the finite element method(FEM).

Speed Control of Linear Induction Motor using Sliding Mode Controller Considering the End Effects

  • Boucheta, A.;Bousserhane, I.K.;Hazzab, A.;Sicard, P.;Fellah, M.K.
    • Journal of Electrical Engineering and Technology
    • /
    • v.7 no.1
    • /
    • pp.34-45
    • /
    • 2012
  • In the present paper, the mover speed control of a linear induction motor (LIM) using a sliding mode control design is proposed, considering the end effects. First, the indirect field-oriented control LIM is derived, considering the end effects. The sliding mode control design is then investigated to achieve speed- and flux-tracking under load thrust force disturbance. The numerical simulation results of the proposed scheme present good performances in comparison to that of the classical sliding mode control.

Effects on the Escapement of Juvenile Bastard Halibut Paralichthys olivaceus of Actively Stimulating Devices Inside a Model Cod End

  • Kim, Yong-Hae
    • Fisheries and aquatic sciences
    • /
    • v.14 no.1
    • /
    • pp.62-69
    • /
    • 2011
  • The effects of actively stimulating devices (ASD) on juvenile flatfish escape were studied to increase escape rates from the cod end by encouraging fish to approach the net wall. Two kinds of ASD were designed: a fluttering net panel, i.e., a free-end flag-like net panel, and a double conical rope array. Escape responses of juvenile bastard halibut were observed in a circulating water channel using two model cod ends, one made with diamond-shaped 43-mm-mesh-size polyethylene (PE) as a high-contrast cod end and the other with polyamid (PA) mono-ply as a low-contrast cod end. Retention rate was significantly lower with the double conical rope-array ASD in the PE cod end than with conventional PE cod ends only or the fluttering net-panel ASD inside the PE cod end. Mean retention rate with the low-contrast PA cod end was also significantly lower than that with the high-contrast PE conventional cod end. Therefore, active fluttering devices using a double conical rope array together with less visible low-contrast netting in the cod end could help to reduce the bycatch of juvenile flatfish by weakening their optomotor response and actively driving fish to the side net panel.

A Study On Effects of The Termination Conditions on Crosstalk in The A/D Converter Circuit (A/D 변환기 회로에서 터미네이션 임피던스의 crosstalk에 대한 영향 분석)

  • Lim, Han-Sang
    • Journal of the Institute of Electronics Engineers of Korea SC
    • /
    • v.47 no.2
    • /
    • pp.35-42
    • /
    • 2010
  • In this study, crosstalk between dominant interconnect pairs in an A/D converter circuit is analyzed in frequency domain and effects of termination conditions on crosstalk are described, based on the practical circuit conditions. An A/D converter circuit is a mixed circuit where both clean and noisy signals coexist such that the circuit probably suffers from distortion by crosstalk. An analog input signal and the reference voltage signal, which dominate the overall conversion performance of the A/D converter circuit, are ready to be distorted by crosstalk and include specific termination conditions, such as non-matching and capacitive termination, respectively. Thus, this study presents the model of crosstalk considering impedance mismatch at both ends and analyzes effects of the practical termination conditions in the analog input and the reference voltage interconnects on crosstalk. A typical circuit configuration of the two interconnects is described and crosstalk including near-end and far-end termination impedances is modeled. Effects of the near-end impedance mismatch in the analog input interconnect and the far-end capacitive termination in the reference voltage interconnect are estimated in the frequency domain by using the model of crosstalk and experiments are performed to confirm the estimated results. Microstrip lines are used as interconnects, involving the increase of loss in high frequencies.

Excitation Temperature and Electron Number Density Measured for End-On-View Indectively Coupled Plasma Discharge

  • Nam, Sang Ho;Kim, Yeong Jo
    • Bulletin of the Korean Chemical Society
    • /
    • v.22 no.8
    • /
    • pp.827-832
    • /
    • 2001
  • The excitation temperature and electron number density have been measured for end-on-view ICP discharge. In this work, end-on-view ICP-AES equipped with the newly developed “optical plasma interface (OPI)” was used to eliminate or remove the neg ative effects caused by end-on-plasma source. The axial excitation temperature was measured using analyte (Fe I) emission line data obtained with end-on-view ICP-AES. The axial electron number density was calculated by Saha-Eggert ionization equilibrium theory. In the present study, the effects of forward power, nebulizer gas flow rate and the presence of Na on the excitation temperature and electron number density have been investigated. For sample introduction, two kinds of nebulizers (pneumatic and ultrasonic nebulizer) were utilized.

  • PDF

Characteristic Analysis of a Linear Induction Motor considering Static and Dynamic End Effect (정적 및 동적 단부효과를 고려한 선형유도전동기의 특성 해석)

  • Kim, Dae-Kyong;Kwon, Byung-Il;Woo, Kyung-Il
    • Proceedings of the KIEE Conference
    • /
    • /
    • pp.981-983
    • /
    • 2000
  • Linear induction motors have static and dynamic end effects due to its finite core length, so that per-phase impedances are asymmetric and the air gap flux distribution is distorted. Because of these points the d-q equivalent circuit model considering both end effects has not been exactly completed. So this paper proposes a characteristic analysis method considering both static and dynamic end effect of the LIM. This method is to utilize asymmetric d-q equivalent circuit model with dynamic end effect coefficient. As a result, it is shown that the simulation results have a good agreement with experimental ones.

  • PDF

A Consideration of Open End & Step Discontinuity Effects for Suspended Strip Line (Suspended Strip Line의 Open End 및 Step 불연속 효과에 대한 고찰)

  • Jeon, Yong-Ku;Yang, Seung-In
    • Journal of the Institute of Electronics Engineers of Korea TC
    • /
    • v.45 no.12
    • /
    • pp.146-151
    • /
    • 2008
  • The equivalent circuits of Open End and Step discontinuity effects for Suspended Strip line are obtained. The circuit parameters for each discontinuity effect are represented by equations after optimization based on EM analysis results, and the coefficients of the equations are obtained by curve fitting for all impedance cases.