In order to improve the hard magnetic properties of MnAl alloy, it is critical to fabricate fine τ phase MnAl powders. In addition, a rapid cooling process and an addition of stabilization elements are required to fabricate a homogeneous phase because a τ phase is a metastable structure. In this study, τ-Mn54Al(46-x)C(x) (x = 0, 1, 2) powders were prepared by melt-spinning and subsequent annealing and milling processes.
View Article and Find Full Text PDFJ Nanosci Nanotechnol
November 2015
Increasing the remanence value of bulk permanent magnets is a critical issue to increase their maximum energy product ((BH)(max)) value. Currently, the enhancement of magnetic alignment is known to come close to the engineering limit. In this study, we investigated the effect of a magnetic layered structure on the remanence value using strontium ferrite and AlNiCo.
View Article and Find Full Text PDFIEEE Trans Image Process
February 2014
In digital forensics, recovery of a damaged or altered video file plays a crucial role in searching for evidences to resolve a criminal case. This paper presents a frame-based recovery technique of a corrupted video file using the specifications of a codec used to encode the video data. A video frame is the minimum meaningful unit of video data.
View Article and Find Full Text PDFMagnetic properties and microstructures of iron-based nanopowders fabricated by several methods, such as sol-gel, thermal decomposition, and self-propagating combustion methods, were investigated. During a subsequent reduction annealing, added aluminum atoms formed coherent oxide shells with a hercynite structure around iron cores in all the nanopowders. In particular, the nanopowders synthesized by the self-propagating combustion method showed the highest saturation magnetization of 175.
View Article and Find Full Text PDFThis paper describes a method for verifying the authenticity of a seal impression imprinted on a document based on the seal overlay metric, which refers to the ratio of an effective seal impression pattern and the noise in the neighborhood of the reference impression region. A reference seal pattern is obtained by taking the average of a number of high-quality impressions of a genuine seal. A target seal impression to be examined, often on paper with some background texts and lines, is segmented out from the background by an adaptive threshold applied to the histogram of color components.
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