Deep Neural Networks for the Recognition and Classification of Heart Murmurs Using Neuromorphic Auditory Sensors

Auscultation is one of the most used techniques for detecting cardiovascular diseases, which is one of the main causes of death in the world. Heart murmurs are the most common abnormal finding when a patient visits the physician for auscultation. These heart sounds can either be innocent, which are harmless, or abnormal, which may be a sign of a more serious heart condition. However, the accuracy rate of primary care physicians and expert cardiologists when auscultating is not good enough to avoid most of both type-I (healthy patients are sent for echocardiogram) and type-II (pathological patients are sent home without medication or treatment) errors made. In this paper, the authors present a novel convolutional neural network based tool for classifying between healthy people and pathological patients using a neuromorphic auditory sensor for FPGA that is able to decompose the audio into frequency bands in real time. For this purpose, different networks have been trained with the heart murmur information contained in heart sound recordings obtained from nine different heart sound databases sourced from multiple research groups. These samples are segmented and preprocessed using the neuromorphic auditory sensor to decompose their audio information into frequency bands and, after that, sonogram images with the same size are generated. These images have been used to train and test different convolutional neural network architectures. The best results have been obtained with a modified version of the AlexNet model, achieving 97% accuracy (specificity: 95.12%, sensitivity: 93.20%, PhysioNet/CinC Challenge 2016 score: 0.9416). This tool could aid cardiologists and primary care physicians in the auscultation process, improving the decision making task and reducing type-I and type-II errors.Ministerio de Economía y Competitividad TEC2016-77785-

NAVIS: Neuromorphic Auditory VISualizer Tool

This software presents diverse utilities to perform the first post-processing layer taking the neuromorphic auditory sensors (NAS) information. The used NAS implements in FPGA a cascade filters architecture, imitating the behavior of the basilar membrane and inner hair cells and working with the sound information decomposed into its frequency components as spike streams. The well-known neuromorphic hardware interface Address-Event-Representation (AER) is used to propagate auditory information out of the NAS, emulating the auditory vestibular nerve. Using the information packetized into aedat files, which are generated through the jAER software plus an AER to USB computer interface, NAVIS implements a set of graphs that allows to represent the auditory information as cochleograms, histograms, sonograms, etc. It can also split the auditory information into different sets depending on the activity level of the spike streams. The main contribution of this software tool is that it allows complex audio post-processing treatments and representations, which is a novelty for spike-based systems in the neuromorphic community and it will help neuromorphic engineers to build sets for training spiking neural networks (SNN).Ministerio de Economía y Competitividad TEC2012-37868-C04-0

Stereo Matching in Address-Event-Representation (AER) Bio-Inspired Binocular Systems in a Field-Programmable Gate Array (FPGA)

In stereo-vision processing, the image-matching step is essential for results, although it involves a very high computational cost. Moreover, the more information is processed, the more time is spent by the matching algorithm, and the more ine cient it is. Spike-based processing is a relatively new approach that implements processing methods by manipulating spikes one by one at the time they are transmitted, like a human brain. The mammal nervous system can solve much more complex problems, such as visual recognition by manipulating neuron spikes. The spike-based philosophy for visual information processing based on the neuro-inspired address-event-representation (AER) is currently achieving very high performance. The aim of this work was to study the viability of a matching mechanism in stereo-vision systems, using AER codification and its implementation in a field-programmable gate array (FPGA). Some studies have been done before in an AER system with monitored data using a computer; however, this kind of mechanism has not been implemented directly on hardware. To this end, an epipolar geometry basis applied to AER systems was studied and implemented, with other restrictions, in order to achieve good results in a real-time scenario. The results and conclusions are shown, and the viability of its implementation is proven.Ministerio de Economía y Competitividad TEC2016-77785-

Sound Recognition System Using Spiking and MLP Neural Networks

In this paper, we explore the capabilities of a sound classification system that combines a Neuromorphic Auditory System for feature extraction and an artificial neural network for classification. Two models of neural network have been used: Multilayer Perceptron Neural Network and Spiking Neural Network. To compare their accuracies, both networks have been developed and trained to recognize pure tones in presence of white noise. The spiking neural network has been implemented in a FPGA device. The neuromorphic auditory system that is used in this work produces a form of representation that is analogous to the spike outputs of the biological cochlea. Both systems are able to distinguish the different sounds even in the presence of white noise. The recognition system based in a spiking neural networks has better accuracy, above 91 %, even when the sound has white noise with the same power.Ministerio de Economía y Competitividad TEC2012-37868-C04-02Junta de Andalucía P12-TIC-130

A Sensor Fusion Horse Gait Classification by a Spiking Neural Network on SpiNNaker

The study and monitoring of the behavior of wildlife has always been a subject of great interest. Although many systems can track animal positions using GPS systems, the behavior classification is not a common task. For this work, a multi-sensory wearable device has been designed and implemented to be used in the Doñana National Park in order to control and monitor wild and semiwild life animals. The data obtained with these sensors is processed using a Spiking Neural Network (SNN), with Address-Event-Representation (AER) coding, and it is classified between some fixed activity behaviors. This works presents the full infrastructure deployed in Doñana to collect the data, the wearable device, the SNN implementation in SpiNNaker and the classification results.Ministerio de Economía y Competitividad TEC2012-37868-C04-02Junta de Andalucía P12-TIC-130

Event-based Row-by-Row Multi-convolution engine for Dynamic-Vision Feature Extraction on FPGA

Neural networks algorithms are commonly used to recognize patterns from different data sources such as audio or vision. In image recognition, Convolutional Neural Networks are one of the most effective techniques due to the high accuracy they achieve. This kind of algorithms require billions of addition and multiplication operations over all pixels of an image. However, it is possible to reduce the number of operations using other computer vision techniques rather than frame-based ones, e.g. neuromorphic frame-free techniques. There exists many neuromorphic vision sensors that detect pixels that have changed their luminosity. In this study, an event-based convolution engine for FPGA is presented. This engine models an array of leaky integrate and fire neurons. It is able to apply different kernel sizes, from 1x1 to 7x7, which are computed row by row, with a maximum number of 64 different convolution kernels. The design presented is able to process 64 feature maps of 7x7 with a latency of 8.98 s.Ministerio de Economía y Competitividad TEC2016-77785-

Accuracy Improvement of Neural Networks Through Self-Organizing-Maps over Training Datasets

Although it is not a novel topic, pattern recognition has become very popular and relevant in the last years. Different classification systems like neural networks, support vector machines or even complex statistical methods have been used for this purpose. Several works have used these systems to classify animal behavior, mainly in an offline way. Their main problem is usually the data pre-processing step, because the better input data are, the higher may be the accuracy of the classification system. In previous papers by the authors an embedded implementation of a neural network was deployed on a portable device that was placed on animals. This approach allows the classification to be done online and in real time. This is one of the aims of the research project MINERVA, which is focused on monitoring wildlife in Do˜nana National Park using low power devices. Many difficulties were faced when pre-processing methods quality needed to be evaluated. In this work, a novel pre-processing evaluation system based on self-organizing maps (SOM) to measure the quality of the neural network training dataset is presented. The paper is focused on a three different horse gaits classification study. Preliminary results show that a better SOM output map matches with the embedded ANN classification hit improvement.Junta de Andalucía P12-TIC-1300Ministerio de Economía y Competitividad TEC2016-77785-

Multilayer Spiking Neural Network for Audio Samples Classification Using SpiNNaker

Audio classification has always been an interesting subject of research inside the neuromorphic engineering field. Tools like Nengo or Brian, and hardware platforms like the SpiNNaker board are rapidly increasing in popularity in the neuromorphic community due to the ease of modelling spiking neural networks with them. In this manuscript a multilayer spiking neural network for audio samples classification using SpiNNaker is presented. The network consists of different leaky integrate-and-fire neuron layers. The connections between them are trained using novel firing rate based algorithms and tested using sets of pure tones with frequencies that range from 130.813 to 1396.91 Hz. The hit rate percentage values are obtained after adding a random noise signal to the original pure tone signal. The results show very good classification results (above 85 % hit rate) for each class when the Signal-to-noise ratio is above 3 decibels, validating the robustness of the network configuration and the training step.Ministerio de Economía y Competitividad TEC2012-37868-C04-02Junta de Andalucía P12-TIC-130

Hábitos deportivos de la población ecuatoriana en la ciudad de Madrid: análisis de su influencia en el proceso de integración en la sociedad española

This paper presents the results of a research work on the sporting habits of the immigrant population from Ecuador in the city of Madrid and the influence of their sport practice in their integration into Spanish society.The sample consisted of 288 ecuadorians (161 men and 127 women), aged between 17 and 64.The methodology was based on the Acculturation Model of Berry et al. (2006) and the Relative Acculturation Extended Model of Navas et al. (2004) The instrument for data collection was a questionnaire developed from the works of Navas et al. (2004), Berry (2002 & 2006), Taylor (2000), Nehas (2000), Reshef (1990) and García Ferrando (2001).The results of this research might be very usefull both for the sport policies aimed at promoting the integration of immigrants in host societies, and for the management and planning of programs and interventions related to sports and immigration.Este artículo presenta los resultados de una investigación sobre los hábitos deportivos de la población inmigrante ecuatoriana en la ciudad de Madrid y el grado de influencia que ejerce la práctica deportiva en su integración en la sociedad española.La muestra estuvo constituida por 288 personas ecuatorianas (161 varones y 127 mujeres) con una edad comprendida entre los 17 y 64 años.El diseño metodológico se basó en el Modelo de Aculturación de Berry y col. (2006) y el Modelo Ampliado de Aculturación Relativa (MAAR) de Navas y col. (2004) El instrumento para la recogida de datos fue el cuestionario, elaborado a partir de los trabajos de Navas y col., Berry (2002 y 2006), Taylor (2000), Nehas (2000), Reshef (1990) y García Ferrando (2001).Los resultados de esta investigación pueden ser de gran utilidad tanto en la adopción de políticas deportivas que favorezcan la integración de la población inmigrante en las sociedades de acogida, como en la gestión y planificación de programas deportivos orientados a la población inmigrante

Hábitos deportivos de la población ecuatoriana en la ciudad de Madrid: análisis de su influencia en el proceso de integración en la sociedad española

Este artículo presenta los resultados de una investigación sobre los hábitos deportivos de la población inmigrante ecuatoriana en la ciudad de Madrid y el grado de influencia que ejerce la práctica deportiva en su integración en la sociedad española.La muestra estuvo constituida por 288 personas ecuatorianas (161 varones y 127 mujeres) con una edad comprendida entre los 17 y 64 años.El diseño metodológico se basó en el Modelo de Aculturación de Berry y col. (2006) y el Modelo Ampliado de Aculturación Relativa (MAAR) de Navas y col. (2004) El instrumento para la recogida de datos fue el cuestionario, elaborado a partir de los trabajos de Navas y col., Berry (2002 y 2006), Taylor (2000), Nehas (2000), Reshef (1990) y García Ferrando (2001).Los resultados de esta investigación pueden ser de gran utilidad tanto en la adopción de políticas deportivas que favorezcan la integración de la población inmigrante en las sociedades de acogida, como en la gestión y planificación de programas deportivos orientados a la población inmigrante.This paper presents the results of a research work on the sporting habits of the immigrant population from Ecuador in the city of Madrid and the influence of their sport practice in their integration into Spanish society.The sample consisted of 288 ecuadorians (161 men and 127 women), aged between 17 and 64.The methodology was based on the Acculturation Model of Berry et al. (2006) and the Relative Acculturation Extended Model of Navas et al. (2004) The instrument for data collection was a questionnaire developed from the works of Navas et al. (2004), Berry (2002 & 2006), Taylor (2000), Nehas (2000), Reshef (1990) and García Ferrando (2001).The results of this research might be very usefull both for the sport policies aimed at promoting the integration of immigrants in host societies, and for the management and planning of programs and interventions related to sports and immigration