Amazigh Spoken Digit Recognition using a Deep Learning Approach based on MFCC

The field of speech recognition has made human-machine voice interaction more convenient. Recognizing spoken digits is particularly useful for communication that involves numbers, such as providing a registration code, cellphone number, score, or account number. This article discusses our experience with Amazigh\u27s Automatic Speech Recognition (ASR) using a deep learning- based approach. Our method involves using a convolutional neural network (CNN) with Mel-Frequency Cepstral Coefficients (MFCC) to analyze audio samples and generate spectrograms. We gathered a database of numerals from zero to nine spoken by 42 native Amazigh speakers, consisting of men and women between the ages of 20 and 40, to recognize Amazigh numerals. Our experimental results demonstrate that spoken digits in Amazigh can be recognized with an accuracy of 91.75%, 93% precision, and 92% recall. The preliminary outcomes we have achieved show great satisfaction when compared to the size of the training database. This motivates us to further enhance the system\u27s performance in order to attain a higher rate of recognition. Our findings align with those reported in the existing literature

Étude et analyse de la réponse électro-optique temporelle : Applications à la caractérisation de plusieurs cristaux optiques non linéaires et à l'optimisation des cellules de Pockels pour le déclenchement d'impulsion laser

Not availableDans ce mémoire, nous avons établi, dans un premier temps, le cahier des charges d'une cellule de Pockels. Nous avons ainsi défini un ensemble de facteurs de mérite qui dépendent de plusieurs paramètres physiques : propriétés électro-optique, conductivité thermique et électrique... Dans un second temps, nous avons mis au point une technique de caractérisation EO basée sur la réponse temporelle du matériau à des échelons de tensions permettant l'obtention des différentes contributions (acoustique et ionique). Nous avons ensuite déterminé les différents facteurs de mérite pour plusieurs cristaux susceptibles d'intégrer une cellule de Pockels : LiNbO3 dans les deux compositions congruente et stoechiométrique, LiTaO3, KTP et BBO. L'ensemble de cette étude a mis en évidence l'avantage d'utiliser un cristal de LiNbO3 stoechiométrique dans une cellule de Pockels

Étude et analyse de la réponse électro-optique temporelle (Applications à la caractérisation de plusieurs cristaux optiques non linéaires et à l'optimisation des cellules de Pockels pour le déclenchement d'impulsion laser)

METZ-SCD (574632105) / SudocSudocFranceF

Frequency and Temperature Effects on Dielectric Properties of PEDOT-VC Copolymer

The copolymer based on Poly(3, 4-Ethylene dioxythiophen) and Poly(n-Vinylcarbazole) was characterized by FTIR and Raman spectroscopy. The temperature and frequency evolutions of dielectric parameters are also plotted and studied. The dependence of ε” on the temperature shows relaxation process for studied copolymer especially with frequencies about 1kHz for the temperatures: 90°C < T < 118°C. The values of ε’∞, ε’’MAX, relaxation time and DC conductivity corresponding to the copolymer are also determined with the aim to provide dielectric analysis involving vital information about this new polymeric compound

Comparative study of nonlinear crystals for electro-optic Q-switching of laser resonators

International audienceThe development of Pockels cells is closely related to the choice of the crystals which are involved in this kind of device. These crystals must satisfy several requirements. In order to clearly establish the crystal ability for the realization of Pockels cells, we define several figures of merit describing its performances for electro-optic Q-Switch and we use these figures of merit to compare the efficiencies of several NLO crystals

Calculation of the dispersion of the electro-optical and second harmonic coefficients from the refractive index dispersion

International audienceThe relationships of the wavelength dependence of both the electro-optic and second harmonic generation coefficients are established within the same model applied to nonlinear optical materials. It is demonstrated that the dispersion of these coefficients can be obtained from the own dependence of the refractive indices only, without any fitted parameter. Solely the measurement of the coefficient at one wavelength is required within this approach. A very good agreement in the -dependence of electrooptic and second harmonic generation coefficients is achieved between calculated values and experimental data in SBN, DAST, KTP and KNbO3 crystals

A New Local Descriptor Based on Strings for Face Recognition

This paper proposes the use of strings as a new local descriptor for face recognition. The face image is first divided into nonoverlapping subregions from which the strings (words) are extracted using the principle of chain code algorithm and assigned into the nearest words in a dictionary of visual words (DoVW) with the Levenshtein distance (LD) by applying the bag of visual words (BoVW) paradigm. As a result, each region is represented by a histogram of dictionary words. The histograms are then assembled as a face descriptor. Our methodology depends on the path pursued from a starting pixel and do not require a model as the other approaches from the literature. Therefore, the information of the local and global properties of an object is obtained. The recognition is performed by using the nearest neighbor classifier with the Hellinger distance (HD) as a comparison between feature vectors. The experimental results on the ORL and Yale databases demonstrate the efficiency of the proposed approach in terms of preserving information and recognition rate compared to the existing face recognition methods