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# IEEE Transactions on Magnetics

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Displaying Results 1 - 25 of 32
• ### [Front cover]

Publication Year: 2007, Page(s): C1
| PDF (181 KB)
• ### IEEE Transactions on Magnetics publication information

Publication Year: 2007, Page(s): C2
| PDF (36 KB)

Publication Year: 2007, Page(s):1869 - 1870
| PDF (59 KB)
• ### Surface and Interior Magnetic Domain Structures of $langle 110 rangle$ Oriented Tb–Dy–Fe Alloy Rods

Publication Year: 2007, Page(s):1871 - 1874
Cited by:  Papers (5)
| | PDF (400 KB) | HTML

We investigated the surface and interior magnetic domains by using magnetic force microscopy for two types of Tb0.3Dy0.7 Fe1.95 crystal growing along the lang110rang direction: 1) crystals annealed at 673 K for 2 h in higher vacuum (5times10-5 Pa) and 2) crystals annealed at 723 K for 2 h in lower vacuum (5times10-3 Pa). For the former, we obs... View full abstract»

• ### Performance and Stability of Soft Magnetic Elements for Electronic Article Surveillance

Publication Year: 2007, Page(s):1875 - 1879
| | PDF (202 KB) | HTML

A simple figure of merit is proposed to compare the performance of soft magnetic elements for electronic article surveillance (EAS) applications. Annealing experiments were carried out to quantify the evolution of soft magnetic properties of amorphous-metal and Permalloy ribbons used in the library EAS industry. By fitting the kinetics of coercivity change to a simple model based on a uniformly di... View full abstract»

• ### Experimental Determination of the Nonuniform Shape-Induced Anisotropy Field in Thin Ni–Fe Films

Publication Year: 2007, Page(s):1880 - 1883
Cited by:  Papers (6)
| | PDF (179 KB) | HTML

We have determined the nonuniform distribution of the shape-induced magnetic anisotropy field for patterned thin films of Ni-Fe. To do this, we used integrated microstrip structures with different widths on identically patterned Ni-Fe cores to act as probes of the internal magnetic field. We verified the accuracy of the field profiles by comparing them with M-H loop measurements of the magnetic fi... View full abstract»

• ### Precision and Accuracy Study on Measurement of Soft Magnetic Properties Using DC Hysteresigraphs

Publication Year: 2007, Page(s):1884 - 1887
Cited by:  Papers (3)
| | PDF (106 KB) | HTML

We report on an interlaboratory study on the precision and accuracy of determining dc soft magnetic properties, under the auspices of ASTM Committee A06 on Magnetic Properties. For certain quantities, the significant differences in the between-laboratory reproducibility results for high-permeability materials indicate that there is a need for improvement in the equipment and software procedures of... View full abstract»

• ### Analysis of Power Magnetic Components With Nonlinear Static Hysteresis: Proper Orthogonal Decomposition and Model Reduction

Publication Year: 2007, Page(s):1888 - 1897
Cited by:  Papers (16)
| | PDF (1122 KB) | HTML

We applied the proper orthogonal decomposition (POD) method to extract reduced-order models to efficiently solve nonlinear electromagnetic problems governed by Maxwell's equations with nonlinear hysteresis at low frequency (10 kHz), called static hysteresis, discretized by a finite-element method. We used a new domain-wall-motion hysteresis model for Power MAgnetic Components (POMACs) in the finit... View full abstract»

• ### Halbach Cylinders With Improved Field Homogeneity and Tailored Gradient Fields

Publication Year: 2007, Page(s):1898 - 1902
Cited by:  Papers (8)
| | PDF (929 KB) | HTML

We show that designs based on Halbach cylinders with a linearly increasing inner bore radius can improve the magnetic field homogeneity or can be used to tailor the spatial variation of the field gradient. We compare our first design to those based on existing methods of increasing the field homogeneity and show that it achieves a twofold improvement in the homogeneity over the next best design. W... View full abstract»

• ### Designing Static Fields for Unilateral Magnetic Resonance by a Scalar Potential Approach

Publication Year: 2007, Page(s):1903 - 1911
Cited by:  Papers (12)  |  Patents (2)
| | PDF (458 KB) | HTML

We present a method for designing single-sided magnets suitable for unilateral magnetic resonance (UMR) measurements. The method uses metal pole pieces to shape the field from permanent magnets in a target region. The pole pieces are shaped according to solutions to Laplace's equation, and can be designed using a combination of analytical methods and numerical optimization. The design leads to ana... View full abstract»

• ### Simple Frequency Domain Model for Hysteresis and Eddy Currents in Cylindrical and Parallelepipedal Cores

Publication Year: 2007, Page(s):1912 - 1919
Cited by:  Papers (7)
| | PDF (500 KB) | HTML

We develop a simple and approximate model for hysteresis and eddy currents in cylindrical magnetic cores. The model characterizes the core by the magnetic properties of its material (mu,psi0, and sigma) and its geometry (perimeter and area of cross section and core length). The model is compatible with common electrical simulators, such as spice, and allows a fast and approximate comput... View full abstract»

• ### A QR Accelerated Volume-to-Surface Boundary Condition for the Finite-Element Solution of Eddy-Current Problems

Publication Year: 2007, Page(s):1920 - 1933
Cited by:  Papers (2)
| | PDF (1675 KB) | HTML

We are concerned with the solution of time-dependent electromagnetic eddy-current problems using a finite-element formulation on three-dimensional unstructured meshes. We allow for multiple conducting regions, and our goal is to develop an efficient computational method that does not require a computational mesh of the air/vacuum regions. This requires a sophisticated global boundary condition spe... View full abstract»

• ### Planes of Continuous-Wave Oscillations From an Electron Nanocontact Spin-Transfer Device

Publication Year: 2007, Page(s):1934 - 1940
Cited by:  Papers (1)
| | PDF (414 KB) | HTML

We have found that the frequencies of continuous-wave (CW) microwave oscillations in nanocontact spin-transfer (ST) devices occur in well-defined planes of frequencies, as a function of the dc current bias, the direction of the magnetic field, and the magnitude of the magnetic field. The frequency, f, of these technologically significant peaks for each magnetic field direction is described empiric... View full abstract»

• ### Filter Capacity Predictions for the Capture of Magnetic Microparticles by High-Gradient Magnetic Separation

Publication Year: 2007, Page(s):1941 - 1949
Cited by:  Papers (14)
| | PDF (532 KB) | HTML

We present experimental and theoretical methods to predict maximum and working filter capacities for the capture of superparamagnetic microparticles through high-gradient magnetic separation (HGMS). For this, we employed various combinations of nine different HGMS filter matrices and two types of superparamagnetic microparticles. By calculating the separated particle mass per filter mesh area, we ... View full abstract»

• ### Motor Core Iron Loss Analysis Evaluating Shrink Fitting and Stamping by Finite-Element Method

Publication Year: 2007, Page(s):1950 - 1954
Cited by:  Papers (28)
| | PDF (2299 KB) | HTML

We describe a method to analyze the effects of shrink fitting and stamping on the mechanical stress distribution and iron loss in motor cores. Shrink fitting and stamping are important processes in manufacture of motor cores from electrical steel. The mechanical stress distribution is evaluated by a structural finite-element method, and the iron loss is evaluated by combined analysis of the electr... View full abstract»

• ### Analytical Modeling of a Permanent-Magnet Synchronous Machine in a Flywheel

Publication Year: 2007, Page(s):1955 - 1967
Cited by:  Papers (56)
| | PDF (774 KB) | HTML

We develop an analytical model for a radial-flux external-rotor permanent-magnet synchronous machine (PMSM) without slots in the stator iron and with a shielding cylinder. The machine is part of an energy storage flywheel, to be used as the peak-power unit in a hybrid electric passenger bus. To reduce the induced no-load losses due to the high rotational speed of the flywheel, the slots in the sta... View full abstract»

• ### Minimizing Thrust Fluctuation in Moving-Magnet Permanent-Magnet Brushless Linear DC Motors

Publication Year: 2007, Page(s):1968 - 1972
Cited by:  Papers (12)
| | PDF (369 KB) | HTML

We present the results of our research on the factors that cause thrust fluctuation in moving-magnet-type permanent-magnet brushless DC linear motors (PMBLDCLM). We combined Fourier transforms and finite-element models to obtain the power spectra of three components of the detent force. We developed a method of optimizing magnet width to minimize the detent force on the basis of harmonic analysis.... View full abstract»

• ### Pulse Shape Improvement in Core-Type High-Voltage Pulse Transformers With Auxiliary Windings

Publication Year: 2007, Page(s):1973 - 1982
Cited by:  Papers (17)
| | PDF (440 KB) | HTML

High-voltage pulsed power technologies are rapidly emerging as a key to efficient and flexible use of electrical power for many industrial applications. One of the most important elements in high-voltage pulse-generating circuit technology is the transformer, generally used to further increase the pulse output voltage level. However, its nonideal behavior has significant influence on the output pu... View full abstract»

• ### Computation of Parameters of Power Transformer Windings for Use in Frequency Response Analysis

Publication Year: 2007, Page(s):1983 - 1990
Cited by:  Papers (28)
| | PDF (2931 KB) | HTML

We present a 3-D model for calculating magnetic fields in a power transformer and the effective parameters (inductance and resistance) of its windings. The transformer is representative of large transformers with power ratings ranging from hundreds of kilovolt amperes to hundreds of megavolt amperes. The model accounts for anisotropic frequency-dependent properties of the laminated transformer cor... View full abstract»

• ### Evaluation of Surface Impedance Models for Axisymmetric Eddy-Current Fields

Publication Year: 2007, Page(s):1991 - 2000
| | PDF (616 KB) | HTML

We have investigated the range of validity of the perfect electric conductor and of the standard Rytov-Leontovich impedance boundary condition models for the analysis of axisymmetric eddy-current problems. Using these models, we derived approximate expressions for the magnetic vector potential, field quantities, Joule losses, and forces for conducting spheroids placed in external nonuniform magnet... View full abstract»

• ### Numerical Modeling of Iron Yoke Levitation Using the Pinning Effect of High-Temperature Superconductors

Publication Year: 2007, Page(s):2001 - 2008
Cited by:  Papers (8)
| | PDF (1172 KB) | HTML

A ferromagnetic material can be levitated by the pinning effect of a field-cooled superconductor. This paper presents two methods for modeling this effect: 1) an approximate calculation to determine the relationship between attractive force and air gap at both room temperature and superconductive temperature (77 K) and 2) a novel way of modeling the pinning effect by a finite-element method (FEM).... View full abstract»

• ### Intelligent Adaptive Backstepping Control System for Magnetic Levitation Apparatus

Publication Year: 2007, Page(s):2009 - 2018
Cited by:  Papers (28)
| | PDF (1152 KB) | HTML

We propose an intelligent adaptive backstepping control system using a recurrent neural network (RNN) to control the mover position of a magnetic levitation apparatus to compensate for uncertainties, including friction force. First, we derive a dynamic model of the magnetic levitation apparatus. Then, we suggest an adaptive backstepping approach to compensate disturbances, including the friction f... View full abstract»

• ### Design and Load/Unload Performance of Hard Disk Drive Suspension Integrated With Shape Memory Alloy Thin Film

Publication Year: 2007, Page(s):2019 - 2024
Cited by:  Patents (1)
| | PDF (729 KB) | HTML

We propose a new load/unload (L/UL) suspension featuring shape memory alloy (SMA) thin film and demonstrate its effectiveness through the L/UL simulation. We estimated the mechanical properties of the SMA with respect to the material phases by experiment and designed the proposed suspension by considering the vibration modes related to the L/UL performance. In order to effectively verify the effec... View full abstract»

• ### Off-Track and Azimuth Angle Effects in Perpendicular Replay

Publication Year: 2007, Page(s):2025 - 2028
Cited by:  Papers (1)
| | PDF (298 KB) | HTML

We investigated the effects of transition curvature on T50 and Vp-p for a shielded giant magnetoresistive (GMR) element reading a single, isolated transition recorded on a perpendicular medium in the presence of a soft magnetic underlayer. We considered displacement and rotation of the read head relative to the recorded track and a range of read head geometries. The curvatur... View full abstract»

• ### Nonrepeatable Run-out Rejection Using Online Iterative Control for High-Density Data Storage

Publication Year: 2007, Page(s):2029 - 2037
Cited by:  Papers (11)
| | PDF (676 KB) | HTML

The spectra of disturbances and noises affecting precise servo positioning for ultrahigh-density storage in future hard disk drives are time-varying and remain unknown. In this paper, we propose an online iterative control algorithm that sets the measured position error signal (PES) into the servo system to achieve high track densities by minimizing the square of the H2-norm of the tran... View full abstract»

## Aims & Scope

IEEE Transactions on Magnetics publishes research in science and technology related to the basic physics and engineering of magnetism, magnetic materials, applied magnetics, magnetic devices, and magnetic data storage.

Full Aims & Scope

## Meet Our Editors

Editor-in-Chief
Pavel Kabos
National Institute of Standards and Technology