4 research outputs found
Magnetic transition and polaron crossover in a two-site single polaron model including double exchange interaction
A two-site double exchange model with a single polaron is studied using a
perturbation expansion based on the modified Lang-Firsov transformation. The
antiferromagnetic to ferromagnetic transition and the crossover from small to
large polaron are investigated for different values of the antiferromagnetic
interaction () between the core spins and the hopping () of the itinerant
electron. Effect of the external magnetic field on the small to large polaron
crossover and on the polaronic kinetic energy are studied. When the magnetic
transition and the small to large polaron crossover coincide for some suitable
range of , the magnetic field has very pronounced effect on the transport.Comment: REVTEX and ps files, accepted in the European Physical Jour.
Polaronic Heat Capacity in The Anderson - Hasegawa Model
An exact treatment of the Anderson - Hasegawa two - site model, incorporating
the presence of superexchange and polarons, is used to compute the heat
capacity. The calculated results point to the dominance of the lattice
contribution, especially in the ferromagnetic regime. This behavior is in
qualitative agreement with experimental findings.Comment: 9 pages, Revtex, 4 postscript figure
AN EFFICIENT FEATURE SELECTION IN CLASSIFICATION OF AUDIO FILES
In this paper we have focused on an efficient feature selection method in classification of audio files. The main objective is feature selection and extraction. We have selected a set of features for further analysis, which represents the elements in feature vector. By extraction method we can compute a numerical representation that can be used to characterize the audio using the existing toolbox. In this study Gain Ratio (GR) is used as a feature selection measure. GR is used to select splitting attribute which will separate the tuples into different classes. The pulse clarity is considered as a subjective measure and it is used to calculate the gain of features of audio files. The splitting criterion is employed in the application to identify the class or the music genre of a specific audio file from testing database. Experimental results indicate that by using GR the application can produce a satisfactory result for music genre classification. After dimensionality reduction best three features have been selected out of various features of audio file and in this technique we will get more than 90 % successful classification result