International audienceThis paper presents a method aimed at recognizing environmental sounds for surveillance and security applications. We propose to apply one-class support vector machines (1-SVMs) together with a sophisticated dissimilarity measure in order to address audio classification, and more specifically, sound recognition. We illustrate the performance of this method on an audio database, which consists of 1015 sounds belonging to nine classes. The database used presents high intraclass diversity in temps of signal properties and some kind of interclass similarities. A large discrepancy in the number of items in each class implies nonuniform probability of sound appearances. The method proceeds as follows: first, the use of a set of state-of-the-art audio features is studied. Then, we introduce a set of novel features obtained by combining elementary features. Experiments conducted on a nine-class classification problem show the superiority of this novel sound recognition method. The best recognition accuracy (96.89%) is obtained when combining wavelet-based features, MFCCs, and individual temporal and frequency features. Our 1-SVM-based multiclass classification approach overperforms the conventional hidden Markov model-based system in the experiments conducted, the improvement in the error rate can reach 50%. Besides, we provide empirical results showing that the single-class SVM outperforms a combination of binary SVMs. Additional experiments demonstrate our method is robust to environmental noise

This paper proposes to apply optimized

Abstract-a Fourier Transform Technique has been used to enhance the genome periodicities when analyzing the distributions of independent nucleotides and dinucleotides. These periodicities are varying from 2 to 500bp. In this paper we focus on the 3 and 10.5 periodicities. The 3-base periodicity is characteristic for the protein-coding sequences only. The source of the approximately 10.5-base sequence period is related to the deformability of DNA. In fact, DNA folding in chromatin is facilitated by periodical positioning of some dinucleotides along the sequences, with the period close to 10.5 bases. When the DNA sequence is encoded for the signal 'AA' or 'TT' or 'TA' the peak at 10.5 is locally strengthened. For the Caenorhabditis elegans (C. Elegans) genome, this peak becomes the dominant feature in the transform. Studying one organism's genome requires three steps. First, the DNA coding method: the DNA's string data are transformed into numerical signal. Second, periodicities are detected by spectral analysis. Third, a 3D graphical representation allows following the evolution of this periodicity along the genome and facilitating the specific regions location.

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