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This paper deals with the thrust calculations and the measurements of a cylindrical linear oscillatory actuator (LOA) using transfer relations theorem (TRT), namely, Melcher's methodology. Using transfer relations derived in terms of a magnetic vector potential and a two-dimensional (2-D) cylindrical coordinate system, this paper derives analytical solutions for the magnetic vector potential, magnetic fields due to permanent magnets (PMs), and stator winding currents and the thrust. The analytical results are validated by nonlinear finite element (FE) analyses. In particular, test results such as thrust and back-EMF (electromotive force) measurements are given to confirm the analysis. Index Terms--Cylindrical linear oscillatory actuator, transfer relations theorem, trust calculations.

This paper deals with design and analysis of the moving-magnet linear actuator with cylindrical Halbach array. On the basis of two- dimensional (2-D) finite-element analysis, this paper predicts thrust characteristics according to design parameters such as magnet height, air-gap length, coil thickness, and pole number. Then, we manufactured equipment made on an experimental basis of moving-magnet linear actuator with cylindrical Halbach array by employing parameters obtained from design results. Finally, this paper presents test results such as thrust measurements, which are given to confirm the finite-element analysis, according to load current and mover position. Index Terms--Cylindrical Halbach array, moving-magnet linear actuator, thrust measurements, 2-D finite-element analysis.

The magnetic and electronic properties of chromium-diffused [beta]-SiC(100) was investigated using the ab initio pseudopotential plane wave method. It is found that the Cr-adsorbed SiC(100)-p(2 x 1) system shows a half-metallic property and represents stable ferromagnetism with 4 [[beta].sub.B] magnetic moments. On the contrary, a half-metallic property could not be found for SiC(100):Cr-c(4 x 2) and -c(2 x 2) systems due to the surface electronic states of SiC(100). Index Terms--[beta]-SiC, diluted magnetic semiconductors (DMS), electronic structure, energetic stability, surface formation energy.

This paper deals with the dynamic characteristic analysis and experiments of moving-magnet linear actuator with cylindrical Halbach array. On the basis of two-dimensional analytical solutions and experiments, control parameters are obtained. Then, a dynamic simulation algorithm is established from a voltage and motion equation. Finally, for various values of frequency, dynamic simulation results for characteristics of voltage, current, and displacement of moving-magnet linear actuator are presented and confirmed through the experiments. Index Terms--Analytical solutions, dynamic characteristic analysis, moving-magnet linear actuator.

This paper deals with analysis and experiments of moving-magnet linear actuators with cylindrical Halbach arrays. On the basis of analytical two-dimensional field solutions, this paper predicts magnetic fields, thrust, flux linkage, and back electromagnetic fluctuation. The results are validated extensively by comparison with finite element analysis. Test results such as thrust measurements are also given to confirm the analysis. Index Terms--Cylindrical Halbach array, moving-magnet linear actuator, thrust measurements.

This paper deals with the comparison of two types of permanent magnet high-speed machines. Specifically, the effect of permanent magnet magnetization pattern on the rotor losses is investigated. On the basis of analytical field analysis and two-dimensional (2-D) finite-element method, this paper predicts the flux harmonics and rotor losses under no-load condition. It is shown that the Halbach magnetization is superior to parallel magnetization in terms of producing rotor losses. Index Terms--Flux harmonics, Halbach magnetization, high-speed machines, magnetization pattern, rotor losses.

This paper reports on the comparison of two types of high-speed slotless permanent magnet machines with the rotor eccentricity as the motor/generator for an electromechanical battery. Using a two-dimensional finite-element method, this paper deals with the magneto static field and unbalanced forces. Specifically, the advantages of Halbach array are discussed when the rotor has eccentricity. Index Terms--Eccentricity, Halbach array, high speed, slotless permanent magnet machine, unbalanced force.

This paper deals with temperature performance of induction heating roll with or without heat pipes. The focus of this paper is to improve nonuniformity of the outer surface temperature of the roll by inserting heat pipes with very high thermal conductivity. In our work, the coupled magneto-thermal finite-element analysis considering skin effect is employed for evaluating the surface temperature. The predicted results are verified with experimental data. Index Terms--Coupled magneto-thermal finite-element analysis (FEA), heat pipe, induction heating, temperature performance.

The authors apply permanent magnet movers with three different magnetization patterns to a linear eddy-current braking system. Using a two-dimensional analytical technique, this paper deals with the comparison of the design guidelines, magnetic field, required magnet volume, and force capability for three types of linear brakes. The analytical results are also verified by finite-element analyses. Lee, Index Terms--Analytical technique, linear eddy-current braking, magnetization patterns, permanent magnet.

This paper deals with the application of cylindrical Halbach array to a permanent magnet motor capable of producing pure rotary motion, pure linear motion, or helical motion. The proposed motor consists of an exterior polar Halbach quadrupole array for a rotary motion and an interior cylindrical Halbach dipole array for a linear one. The two-dimensional finite-element method is employed for predicting the effect of design parameters of the machine. Index Terms--Cylindrical Halbach array, finite-element method (FEM), helical motion, permanent magnet motor.

Permanent-magnet linear synchronous motors (PMLSMs) with air-cored film coil are applied to servo, miniature, and precision motion-controlled linear machines. On the basis of analytical field solutions, this paper deals with the comparison of the design guidelines, magnetic field, winding electromotive force, required magnet volume, optimal winding thickness, and thrust force for two types of permanent magnet movers. Index Terms--Air-cored film coil, permanent-magnet linear synchronous motor, servo and miniature linear machine.

In order to improve power efficiency, Halbach magnetized topology is applied to a short secondary slotted permanent-magnet linear synchronous motor (PMLSM). Detent force of slotted PMLSMs is due to the interaction between the edges of the permanent magnet and the teeth of the primary core. This paper deals with detent force reduction methods such as adjustment of magnet length and skewing. Reduction effect of detent force and thrust performance for two topologies are also compared. Index Terms--Detent force, Halbach magnetized mover, PMLSM, thrust performance.

We apply a linear Halbach magnetized mover to an eddy-current braking system for high speed. On the basis of analytical two-dimensional field solutions considering end effects, this paper deals with the magnetic field, eddy current distribution, forces according to the secondary relative permeability, and conductivity. We also present comparisons between analytical results and experimental data. Index Terms--Eddy-current braking, end effect, Halbach array, high speed.