International Journal of Applied Electromagnetics and Mechanics - Volume 33, issue 1-2

Authors: Ohno, Takeshi | Takeno, Takanori | Miki, Hiroyuki | Takagi, Toshiyuki

Article Type: Research Article

Abstract: The strain properties of the W-DLC coatings were evaluated. W-DLC coatings with various concentrations were prepared by chemical vapor deposition and DC magnetron co-sputtering of a tungsten metal target. Strain was applied to a sample in a four-point bending configuration. The electrical resistance was proportional to the amount of compression and tensile strain, and the gauge factor varied according to the metal concentration. Transmission electron microscope was employed for structure analyses. It was clarified that the …structure of the W-DLC was granular. The variation of the resistance under the strain could be explained by a simplified model related to the distance between the clusters. The W-DLC coatings have the potential for strain sensor application. Show more

Keywords: Amorphous carbon, strain sensor, smart material

DOI: 10.3233/JAE-2010-1171

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 33, no. 1-2, pp. 665-671, 2010

Authors: Hong, Do-Kwan | Woo, Byung-Chul | Choi, Jae-Hak | Koo, Dae-Hyun

Article Type: Research Article

Abstract: Moving Permanent Magnet (PM) type Longitudinal Flux Linear Motors (LFLMs) are electromagnetic devices which can develop directly powerful linear motion. This paper deals with an effective analysis of PM-type LFLM by Finite Element Method (FEM) and optimum design for lightweight. This paper presents the statistical optimum design of PM-type LFLM to reduce the weight of a moving PM-type linear actuator with the constraint of avg. thrust force using the penalty method with characteristics function and kriging …interpolation method. The contribution and effect of the each design variable on the characteristic function is evaluated by the analysis of means (ANOM) and optimum design set is determined. The generalized reduced gradient (GRG) algorithm is adopted in kriging model. Therefore, it is expected that the proposed optimization procedure using penalty method and kriging interpolation method can be easily utilized to solve the optimization problem with constraint of electric machine. Show more

Keywords: Penalty method, characteristic function, kriging interpolation method Analysis of Means (ANOM), statistical optimum design, moving Permanent Magnet (PM) type Longitudinal Flux Linear Motor (LFLM)

DOI: 10.3233/JAE-2010-1172

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 33, no. 1-2, pp. 673-680, 2010

Authors: Shang, Xinchun | Qin, Liping | Wang, Fan

Article Type: Research Article

Abstract: The periodic vibration of a magnetostrictive actuator is analyzed. The problem is described in mathematical as solving the displacement response of a Terfenol-D rod excited by the input harmonic alternating current. The governing equation and boundary condition include periodically variable coefficient with time. As the magnetoelastic coefficient of Terfenol-D is small, a regular perturbation approach is employed to approximately solve the analytic solution of the problem. The displacement response curves and amplitude-frequency …characteristic curves from the presented analytic solution agree well with the numeric solution and the experimental data in reference. The study indicates that the double frequency effect generates in the case of no biasing magnetic field. However for high biasing magnetic field, the output displacement depends in synchronous and linearly on the input current. These features of the solution could provide applicable information for control design of magnetostrictive actuators. Show more

Keywords: Magnetostrictive actuator, Terfenol-D, periodic vibration, analytic solution, double frequency effect

DOI: 10.3233/JAE-2010-1173

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 33, no. 1-2, pp. 681-688, 2010

Authors: You, Yong-Min | Kim, Dae-Kyong | Kwon, Byung-Il

Article Type: Research Article

Abstract: This paper presents the design of a reliable rotor shape of a BLDC motor used for reciprocating compressor considering demagnetization. Three types of rotor shape are proposed for BLDC motor and a proper rotor shape is selected by characteristic analysis using the 2D finite element method (FEM). To verify the accuracy of the analysis results, a prototype was built and tested. In order to design a reliable rotor shape against the demagnetization of the ferrite magnet, …the demagnetization analysis is performed according to variation of design variables of the ferrite magnet using the 2D FEM. As a result, the BLDC motor with the developed rotor shape showed good performance to resist partial demagnetization. Show more

Keywords: Demagnetization, BLDC, Reciprocating Compressor, ferrite magnet, FEM

DOI: 10.3233/JAE-2010-1174

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 33, no. 1-2, pp. 689-695, 2010

Authors: Ishikawa, Takeo | Tsuchitani, Osamu

Article Type: Research Article

Abstract: In this paper, we analyze the steady state characteristics of an experimental capacitor motor by 3-D non-linear FEM coupled with the voltage equation. Next, we propose several methods to improve the motor efficiency by considering the flux density distribution. The motor model where the rotor bars are spread inside can improve the motor efficiency by 4.7%.

Keywords: Capacitor motor, efficiency, finite element method

DOI: 10.3233/JAE-2010-1175

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 33, no. 1-2, pp. 697-704, 2010

Authors: Miki, Hiroyuki | Okuyama, Takeshi | Kodaira, Shingo | Luo, Yun | Takagi, Toshiyuki | Yambe, Tomoyuki | Sato, Takeshi

Article Type: Research Article

Abstract: Artificial esophagus of less invasive medical applications utilizing mechanical property of shape memory alloys (SMAs) with peristaltic motion is developed. The artificial-esophagus is composed of two SMA springs, polyvinyl chloride tube, and acrylic plate. The dynamic characteristics of an artificial-esophagus actuator are evaluated in terms of the food transport capacity. Closing pressure and the transport speed have sufficiently realized with human-like qualities. The possibility for fully self-contained artificial-esophagus using SMAs is discussed.

Keywords: Artificial esophagus, peristaltic motion, shape memory alloy, actuator

DOI: 10.3233/JAE-2010-1176

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 33, no. 1-2, pp. 705-711, 2010

Authors: Zhang, Xiao-Ju | Chen, Min-You | He, Wei | He, Chuan-Hong

Article Type: Research Article

Abstract: In order to reduce the error in image reconstruction caused by changeable positions of the electrodes in Closed Electrical Impedance Tomography (CEIT), an Open EIT (OEIT) model was proposed using fixed electrode array. The problem is assumed to be a virtual field by defining certain local sensitive area instead of solving the boundary problem in the whole electromagnetic field strictly. Modeling and simulation of OEIT have been conducted to determine reasonable boundary parameters and electrode array …structure. The image was reconstructed by iterative Newton-Raphson algorithm with Tikhonov and Variation regularization. The experiment results showed that OEIT achieved good resolution and positioning accuracy, and can be applied to distinguish small difference in conductivity of the biological tissues. Show more

Keywords: Open electrical impedance tomography, modeling, regularization

DOI: 10.3233/JAE-2010-1177

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 33, no. 1-2, pp. 713-720, 2010

Authors: Zhu, Haitao | Demachi, Kazuyuki

Article Type: Research Article

Abstract: Iron concentration is an important parameter for clinical usage of superparamagnetic iron oxide particles. Traditional T_{2} mapping for iron concentration measurement requires several images and long scanning time. This work proposes a method using phase characteristic of magnetic resonance imaging to analyze the magnetic field inhomogeneity caused by superparamagnetic iron oxide particles. Phantom experiments are implemented on 4.7T MRI system. Phase dependence on time of echo and iron concentration is …discussed. Results validate the feasibility of measuring superparamagnetic iron oxide particle concentration by phase data at one single scanning. Show more

Keywords: Magnetic resonance imaging, superparamagnetic iron oxide, phase image

DOI: 10.3233/JAE-2010-1178

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 33, no. 1-2, pp. 721-726, 2010

Authors: Li, Ming | He, Wei | Li, Qian | Xu, Zheng | Luo, Cong

Article Type: Research Article

Abstract: A new numerical integral method of the Hankel transform which included the dual Bessel function in the integrand was presented. Because of the strong-oscillation and slow-decay properties of the Bessel functions, it is impossible to use a normal numerical integration method. In our method, the integral interval [0, ∞) is divided into two parts: [0, λ _0 ] and [λ _0 , ∞). In [0, λ _0 ], the integration can be calculated using …a Gauss-Legendre quadrature method between the adjacent zero points. And in [λ _0 , ∞), the Hankel transform is converted to the Fourier cosine or sine transform, and can be calculated with a polygonal approximation algorithm. The proper value of the dividing point of λ _0 was discussed. The simulation results of the test functions show that the algorithm is correct and accurate. Finally, the forward problem of the multi-layer medium magnetic induction tomography was calculated with this new method, and the eddy current distribution in the model and the induced voltages in the detection coils were simulated. Show more

DOI: 10.3233/JAE-2010-1179

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 33, no. 1-2, pp. 727-734, 2010

Authors: Čáp, Ivo | Čápová, Klára

Article Type: Research Article

Abstract: The paper deals with an electromechanical model of liquid flow in a tube in order to model blood flow in vessels. The present paper deals with detailed mathematical development of a model based on the theory of electrical long line with distributed elements. The detailed derivation of primary parameters of the analogical electric circuit is described. There are presented some results of application of the model like wave impedance and wave vector of the blood pulse …wave, which are important for the model application to the blood vessels system diagnosis. The significant parameter of the pulse wave – the pulse wave velocity (PWV) has been evaluated and the calculated values of phase and group velocities in selected vessels have been confronted with physiological data. Show more

Keywords: Electromechanical analogy, electromechanical models, blood flow in vessels, simulation of physiological functions, mathematical methods in medicine, propagation of blood pulse wave, PWV

DOI: 10.3233/JAE-2010-1180

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 33, no. 1-2, pp. 735-742, 2010