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Full-Text Articles in Physical Sciences and Mathematics
Timing Of Substorm-Associated Auroral Oscillations, P Martin, Niescja E. Turner, J Wanliss
Timing Of Substorm-Associated Auroral Oscillations, P Martin, Niescja E. Turner, J Wanliss
Niescja E. Turner
Previous studies have shown that auroral luminosity oscillations are often associated with substorms. Here we examine photometer data for the magnetospheric substorm on April 1, 2000 (expansive phase onset at 0525 UT) to study the detailed timing of the auroral oscillations relative to onset. Accurate timing information for the periodicities in the photometer data were determined using the wavelet transform. We find that the oscillations occur primarily during the recovery phase. Copyright © The Society of Geomagnetism and Earth
Image Similarity Index Based On Moment Invariants Of Approximation Level Of Discrete Wavelet Transform, Prashan Premaratne, Malin Premaratne
Image Similarity Index Based On Moment Invariants Of Approximation Level Of Discrete Wavelet Transform, Prashan Premaratne, Malin Premaratne
Dr Prashan Premaratne
Subjective quality measures based on the human visual system for images do not agree well with well-known metrics such as mean squared error and peak signal-to-noise ratio. Recently, the structural similarity measure (SSIM) has received acclaim owing to its ability to produce results on a par with the human visual system. However, experimental results indicate that noise and blur seriously degrade the performance of the SSIM metric. Furthermore, despite the SSIM's popularity, it does not provide adequate insight into how it handles the 'structural similarity' of images. Proposed is a new structural similarity measure based on the approximation level of …