Application of an Annular/Sphere Search Algorithm for Speaker Recognition

In this work, an alternative search algorithm for vector quantization codebook is applied as a way to improve the performance of an automatic speaker recognition system. The search algorithm is based on geometrical properties of the vector space, defining annular and spherical regions instead of a full search method. The speaker recognition system is intended to identify a suspect, between a small group of persons, using low quality recordings, working as a text independent automatic speaker recognition system. Because the rate of recognition required in forensic applications is extremely important, the use of good discrimination algorithms can reduce the risk of bad decisions. The performance of the system under such a conditions is reported. Besides the few speaker samples used for training, a high recognition rate was obtained, so it was found an improvement of the recognition rate over the full search method

Image Addition by Computer Generated Multiplexed Holograms

A new approach to perform image addition via computer generated multiplexed holograms is described. The purpose of this work is to handle flat objects that are to be stored in a hologram. When holograms are reconstructed, images appear simultaneously in the same direction and same diffraction order, thus recovering a more complex image. The experimental results demonstrate the suggested procedure

A Texas instruments DSP-based acoustic source direction finder

This document describes the implementation of a DSP-based acoustic source direction finder and its application to control the direction of a steerable camera. For real-time implementation a TMS320F2812 digital signal controller was used. The system can be used for different applications like in teleconferencing rooms or surveillance systems. This report presents a description of the developed system in three phases of the project: direction of arrival estimation, analog interfase, and servomotor control. The application was developed by undergraduate students at the Autonomous University of Zacatecas as a final project in the course “DSPs programming”, which is one of the DSP courses thought in the Communications and Electronics Engineering program, with a major in DSP

Prevalence of Microorganisms and Immunoglobulins in Children with Tonsillar Hypertrophy and Adenoiditis

Introduction: Benign idiopathic tonsillar hypertrophy (HBI) may affect a child's quality of life and sleep. Several studies have sought to relate the clinical features of HBI with the infectious and/or immunologic changes that occur. Objective: To increase the knowledge of the etiology of HBI. Data Synthesis: From 2012 to 2013 we conducted a retrospective observational study of 101 children with HBI who underwent tonsillectomies at Ambulatory ENT General Hospital of the East Zone of São Paulo City, a region with a poor socioeconomic population. Preoperative serologic results were available to confirm mononucleosis, cytomegalovirus, anti-streptolysin O (ASLO) and immunoglobulins. The mean patient age was 5.8 years (55% male, 45% female). Using the Mann-Whitney U test, we identified significant gender differences in the parameters of immunoglobulins (Ig) M (IgM), IgA, and IgE. Forty-seven percent of the patients had increased ASLO levels, and 37% had increased IgE levels. Conclusion: An evaluation of a patient's serologic parameters and laboratory results may be relevant to the etiology and prevention of HBI. Based on the results obtained from the study sample, the identification of etiologic agents and causative factors remain a public health challenge that affects the quality of life of children.Universidade Anhembi MorumbiUniversidade Federal de São Paulo (UNIFESP)Universdidade Cidade de São PauloUNIFESP, EPMSciEL

A reduced search algorithm for speaker recognition

In this work, a reduced search algorithm for vector quantization codebooks is applied as a way to reduce the risk of wrong decisions in an automatic speaker recognition system. Instead of a full search method, the algorithm is based on the geometrical properties of the vector space, reducing the search to those codebooks which are closer to the vector under test. The speaker recognition system is intended to identify a suspect, between a small group of persons, using low quality recordings, working as a text independent automatic speaker recognition system. It was found that the alternative search algorithm can be used to reduce the risk of wrong decisions, which is specially important in forensic applications

Implementation of a neuron-based autonomous Mobil Robot on a DSP

An autonomous mobil robot has been implemented on a Digital Signal Processor (for real time operation) using neural networks as the main part of the program that runs on the processor. The neural network was based on a single layer perceptron (SLP) with two neurons, four inputs coming from four sonar sensors, and two outputs to control the direction of two CD motors. The goal of the mobil robot is to avoid obstacles while it runs randomly in a given room. Two training sets were tested to provide two di®erent reactive behaviors, the first one with forward direction, left turn and right turn, and the second which includes reverse direction. Both behaviors were compared

Unraveling the periprandial changes in brain serotonergic activity and its correlation with food intake-related neuropeptides in rainbow trout Oncorhynchus mykiss

This study explored changes in brain serotonin content and activity together with hypothalamic neuropeptide mRNA abundance around feeding time in rainbow trout, as well as the effect of one-day fasting. Groups of trout fed at two (ZT2) and six (ZT6) hours after lights on were sampled from 90 minutes before to 240 minutes after feeding, while additional groups of non-fed trout were also included in the study. Changes in brain amine and metabolite contents were measured in hindbrain, diencephalon and telencephalon, while in the diencephalon the mRNA abundance of tryptophan hydroxylase ( tph1 , tph2 ), serotonin receptors (5htr1a , 5htr1b and 5htr2c ) and several neuropeptides ( npy , agrp1 , cartpt , pomca1 , crfb ) involved in the control of food intake were also assessed. The results showed changes in the hypothalamic neuropeptides that were consistent with the expected role for each in the regulation of food intake in rainbow trout. Serotonergic activity increased rapidly at the time of food intake in the diencephalon and hindbrain and remained high for much of the postprandial period. This increase in serotonin abundance was concomitant with elevated levels of pomca1 mRNA in the diencephalon, suggesting that serotonin might act on brain neuropeptides to promote a satiety profile. Furthermore, serotonin synthesis and neuronal activity appear to increase already before the time of feeding, suggesting additional functions for this amine before and during food intake. Exploration of serotonin receptors in the diencephalon revealed only small changes for gene expression of 5htr1b and 5htr2c receptors during the postprandial phase. Therefore, the results suggest that serotonin may play a relevant role in the regulation of feeding behavior in rainbow trout during periprandial time, but a better understanding of its interaction with brain centers involved in receiving and processing food-related signals is still needed.Agencia Estatal de Investigación | Ref. PID2022-136288OB-C31Xunta de Galicia | Ref. ED431B 2019/37Agencia Estatal de Investigación | Ref. BES-2017-079708Xunta de Galicia | Ref. ED481B-2022-08

Algunas alternativas a la transformada wavelet para la compresión y restauración de señales n-dimensionales

Este trabajo tiene como finalidad presentar un conjunto de nuevas herramientas utilizadas para la restauración y compresión de señales. El análisis mediante la Transformada en Ondículas (TO) o Wavelets ha crecido a grandes pasos gracias a su aplicabilidad en diferentes áreas. Uno de los casos que había preocupado bastante era la inconsistencia de la TO para señales bidimensionales, pues la TO no es capaz de mapear adecuadamente discontinuidades a lo largo de una línea (R) en L_2 o curva en un espacio (R) en L_2 , tal es el caso de los contornos (cerrados o abiertos). Con la finalidad de atacar este problema D. Donoho de la Universidad de Stanford y su equipo de trabajo se han dado a la tarea de proponer nuevas transformaciones que recurren al uso mismo de la teoría de ondículas, estas nuevas herramientas de análisis son conocidas como ridgelets, curvelets, beamlets, contourlets, bandelets, brushlets, y otros más

Diseño De Un Sistema Multicanal Para Sensores De Microdeformaciones

Se reporta el diseño de un sistema multicanal para la adquisición y el procesamiento de señales de muy bajo nivel provenientes de sensores de deformación a base de galgas extensiométricas (strain gauges). Se presenta la descripción de los módulos que componen al sistema, las ecuaciones de diseño, y se incluyen los cálculos de resolución, en micras, y del alcance esperado en las mediciones. El sistema se conecta a cualquier computadora personal a través del puerto serie, e incluye módulos de acondicionamiento de señales con capacidad de 8 canales por módulo. Para la multicanalización de los sensores, se propone un puente de resistencias en configuración Chevron, lo cual representa una simplificación tanto en la construcción como en el número de resistencias que lo componen. Además, una vez calibrado, el sistema no requiere de ajuste manual ya que emplea la técnica de puente desbalanceado

Localización acústica en 3D mediante DTI y DNI en un modelo biomimético usando grabación binaural

Este trabajo presenta el análisis de diferencia de tiempo inter-aural (DTI) y de diferencia de nivel interaural (DNI) para diferentes tonos senoidales puros, usando grabación binaural y un maniquí tipo KEMAR, se obtienen las características de potencia y retardo de los tonos. Estas características permiten la correcta localización de tonos puros