262 research outputs found
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
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