3-D FEM analysis of the effects of SPT head dimensions on recording in discrete and continuous media

Due to the considerable increase of magnetic recording density, the deviation of the head from the centerline of the track becomes a serious problem for the cross-track interference. In this paper, a three-dimensional read/write simulation system was used to investigate the effect of the width of the write head on the behavior of the flux and magnetization for continuous track medium and discrete track medium. It is shown that the magnetization in a neighboring track of the discrete track medium is smaller than that of the continuous track medium. The output of the read head using the discrete track medium is larger than that of the continuous track medium when a suitable read head width is chosen so that the cross talk is negligible.</p

Magnetic shield design of perpendicular magnetic recording head by using topology optimization technique

It is necessary to develop a recording head having large recording field and small stray field to adjacent tracks and adjacent bits in perpendicular magnetic recording system. In this paper, in order to decrease the leakage flux in the adjacent bit, the approach of magnetic shield design of perpendicular magnetic recording head for 200 Gb/in/sup 2/ is performed by using the topology optimization technique.</p

Analysis of writing characteristics of CF-SPT head using 3-D read/write simulation system

Recently, the increase of areal recording density is remarkable. In order to develop a high density recording device, a read/write (R/W) simulation using three dimensional (3-D) magnetic field analysis is indispensable. In this paper, the magnetic field in a cusp-field single-pole-type (CF-SPT) head with discrete track media is analyzed using a 3-D R/W simulation system, in which edge-based finite element method and 3-D medium hysteresis model based on the ensemble of the Stoner-Wohlfarth (SW) particles are combined. The effects of ampereturns and the discrete track media on the distribution of recorded magnetization are investigated. The detailed behavior of flux around the discrete track media and continuous media is illustrated.</p

Welfare Cost of Inflation and Income Risks in an Incomplete Market Model: Application to the Japanese Economy Welfare Costs of Inflation and Income Risks in an Incomplete Market Model: Application to the Japanese Economy *

Abstract This paper quantitatively investigates the welfare costs of inflation and idiosyncratic and aggregate income risks in a Bewley-type incomplete market model. A calibrated model of the Japanese economy in the 1990s indicates that money growth generated a larger welfare cost equivalent to 0.334% of real GDP, than the estimated shoe-leather cost 0.2%, and that the cost of inflation was amplified through an increase in unemployment risk. The model also indicates that longer unemployment duration spells, and the presence of heterogeneous agents, augment the welfare costs of income risk. Finally, the aggregate risk of the business cycle is found to be of little importance to welfare