• Title/Summary/Keyword: Electro-magnetic

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A Study of stimulating plant growth without fertilizers in a electro-magnetic field. (전자기장에 의한 특물성장촉진에 관한 연구)

  • 이문호
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.3 no.1
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    • pp.31-34
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    • 1978
  • This paper is an experimental arrangement developed by the author to test certain theories relative to stimulating plant growth in a electro-magnetic field. It was the invention and use of cheap chemical fertiliazers that effectively suppressed electro-cultural engineering. Today, however, we are in the position where nitrate pollution by these very fertilizers threaten not only our water supply but the entire ecological pancrama as well. Thus it would appear that the revival of electro-culture is not only desirable but imminently necessary.

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Pressure Control Valve using Proportional Electro-magnetic Solenoid Actuator (비례솔레노이드 액추에이터를 이용한 압력제어밸브)

  • Ham Young-Bog;Park Pyoung-Won;Yun So-Nam
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.30 no.10 s.253
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    • pp.1202-1208
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    • 2006
  • This paper presents an experimental characteristics of electro-hydraulic proportional pressure control valve. In this study, poppet and valve body which are assembled into the proportional solenoid were designed and manufactured. The constant force characteristics of proportional solenoid actuator in the control region should be independent of the plunger position in order to be used to control the valve position in the fluid flow control system. The stroke-force characteristics of the proportional solenoid actuator is determined by the shape (or parameters) of the control cone. In this paper, steady state and transient characteristics of the solenoid actuator for electro-hydraulic proportional valve are analyzed using finite element method and it is confirmed that the proportional solenoid actuator has a constant attraction force in the control region independently on the stroke position. The effects of the parameters such as control cone length, thickness and taper length are also discussed.

Analytical solutions to magneto-electro-elastic beams

  • Jiang, Aimin;Ding, Haojiang
    • Structural Engineering and Mechanics
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    • v.18 no.2
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    • pp.195-209
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    • 2004
  • By means of the two-dimensional basic equations of transversely isotropic magneto-electro-elastic media and the strict differential operator theorem, the general solution in the case of distinct eigenvalues is derived, in which all mechanical, electric and magnetic quantities are expressed in four harmonic displacement functions. Based on this general solution in the case of distinct eigenvalues, a series of problems is solved by the trial-and-error method, including magneto-electro-elastic rectangular beam under uniform tension, electric displacement and magnetic induction, pure shearing and pure bending, cantilever beam with point force, point charge or point current at free end, and cantilever beam subjected to uniformly distributed loads. Analytical solutions to various problems are obtained.

Pyroelectric and pyromagnetic effects on behavior of magneto-electro-elastic plate

  • Kondaiah, P.;Shankar, K.;Ganesan, N.
    • Coupled systems mechanics
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    • v.2 no.1
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    • pp.1-22
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    • 2013
  • Under thermal environment, Magneto-Electro-Elastic (MEE) material exhibits pyroelectric and pyromagnetic effects which can be used for enhancing the performance of MEE sensors. Recently studies have been published on material constants such as pyroelectric constant and pyromagnetic constant for magneto-electro-thermo-elastic smart composite. Hence, the main aim of this paper is to study the pyroelectric and pyromagnetic effects on behavior of MEE plate under different boundary conditions subjected to uniform temperature. A numerical study is carried out using eight noded brick finite element under uniform temperature rise of 100 K. The study focused on the pyroelectric and pyromagnetic effects on system parameters like displacements, thermal stresses, electric potential, magnetic potential, electric displacements and magnetic flux densities. It is found that, there is a significant increase in electric potential due to the pyroelectric and pyromagnetic effects. These effects are visible on electric and magnetic potentials when CFFC and FCFC boundary conditions are applied. Additionally, the pyroelectric and pyromagnetic effects at free edge is dominant (nearly thrice the value in CFFC in comparison with FCFC) than at middle of the plate. This study is a significant contribution to sensor applications.

Electro-Optical Characteristic for VA-LCD on the $SiO_x$ Thin Film Layer Oblique Deposited by Sputtering Method (스퍼터링으로 경사증착한 $SiO_x$ 박막을 이용한 VA-LCD의 전기광학특성)

  • Choi, Sung-Ho;Hwang, Jeoung-Yeon;Kim, Sung-Yeon;Oh, Byeong-Yun;Myoung, Jae-Min;Seo, Dae-Shik
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2006.06a
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    • pp.451-452
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    • 2006
  • We studied the electro-optical characteristic of vertical alignment liquid crystal display(VA-LCD) on the $SiO_x$ thin film deposited $45^{\circ}$ oblique by rf magnetic sputtering system. LC alignment characteristic showed homeotropic alignment, and pretilt angle was about $90^{\circ}$. A uniform liquid crystal alignment effect on the $SiO_x$ thin film was achieved and the electro-optical characteristic of the $SiO_x$ thin film deposited $45^{\circ}$ oblique by rf magnetic sputtering system was excellent.

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Electro-magneto-elastic analysis of a three-layer curved beam

  • Arefi, Mohammad;Zenkour, Ashraf M.
    • Smart Structures and Systems
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    • v.19 no.6
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    • pp.695-703
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    • 2017
  • In this paper, based on first-order shear deformation theory, the governing equations of motion for a sandwich curved beam including an elastic core and two piezo-magnetic face-sheets are presented. The curved beam model is resting on Pasternak's foundation and subjected to applied electric and magnetic potentials on the piezo-magnetic face-sheets and transverse loading. The five equations of motion are analytically solved and the bending and vibration results are obtained. The influence of important parameters of the model such as direct and shear parameters of foundation and applied electric and magnetic potentials are studied on the electro-mechanical responses of the problem. A comparison with literatures was performed to validate our formulation and results.

Analysis of Electromagnetic Wave Absorbers for Applying Magnetic Levitation (자기부상체 적용을 위한 전자파 흡수체의 특성 분석)

  • Seo, Yong-beom;Kang, Hyun-il
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.65 no.1
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    • pp.13-17
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    • 2016
  • EMC (Electro Magnetic Compatibility) of the electrical railway must be ensured for safety of passenger. Maglev trains has not friction between the wheels and the rails because levitation by an permanent magnets, electromagnets and superconducting magnets etc. So, it is advantageous to maintain a high speed without noise and vibrations. In this paper, we investigated that the magnetic field of the before and after installation electromagnetic waves absorber in order to analyze the effects of electromagnetic waves. The theoretical analysis of the electromagnetic wave absorber was simulated using finite element method. The magnetic field properties of electromagnetic waves absorber were measured by EMI (Electro Magnetic Interference) test receiver.

Static stability analysis of smart nonlocal thermo-piezo-magnetic plates via a quasi-3D formulation

  • Fenjan, Raad M.;Ahmed, Ridha A.;Faleh, Nadhim M.;Hani, Fatima Masood
    • Smart Structures and Systems
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    • v.26 no.1
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    • pp.77-87
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    • 2020
  • By employing a quasi-3D plate formulation, the present research studies static stability of magneto-electro-thermo-elastic functional grading (METE-FG) nano-sized plates. Accordingly, influences of shear deformations as well as thickness stretching have been incorporated. The gradation of piezo-magnetic and elastic properties of the nano-sized plate have been described based on power-law functions. The size-dependent formulation for the nano-sized plate is provided in the context of nonlocal elasticity theory. The governing equations are established with the usage of Hamilton's rule and then analytically solved for diverse magnetic-electric intensities. Obtained findings demonstrate that buckling behavior of considered nanoplate relies on the variation of material exponent, electro-magnetic field, nonlocal coefficient and boundary conditions.

Characteristics Analysis on the Effects of Rotor Eccentricity in Squirrel-cage Induction Motor (회전자 편심을 고려한 농형 유도전동기의 특성해석)

  • Kim, Mi-Jung;Kim, Byong-Kuk;Hwang, Don-Ha;Kang, Dong-Sik;Cho, Yun-Hyun
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.56 no.2
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    • pp.289-294
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    • 2007
  • This paper describes the effects of rotor eccentricity in squirrel cage induction machines. Asymmetric electro-magnetic force caused by the frictional worn bearing, rotor misalignment and unbalanced rotor etc. generates an asymmetrical operation, vibration and electro-magnetic noise. The need for detection of these rotor eccentricities has pushed the development of monitoring methods with increasing sensitivity and noise immunity. In this paper, we focus on investigating the asymmetrical operation considering of unbalanced magnetic pull in squirrel-cage induction motor with 380 [V], 7.5 [kW], 4P, 1,768 [rpm]. The effects of the non-symmetric rotor and magnetic force are simulated by finite element method (FEM) and tested using search coils for measuring the actual air-gap flux.