948 research outputs found
Adaptive Multi-Pattern Fast Block-Matching Algorithm Based on Motion Classification Techniques
Motion estimation is the most time-consuming subsystem in a video codec. Thus, more efficient methods of motion estimation should be investigated. Real video sequences usually exhibit a wide-range of motion content as well as different degrees of detail, which become particularly difficult to manage by typical block-matching algorithms. Recent developments in the area of motion estimation have focused on the adaptation to video contents. Adaptive thresholds and multi-pattern search algorithms have shown to achieve good performance when they success to adjust to motion characteristics. This paper proposes an adaptive algorithm, called MCS, that makes use of an especially tailored classifier that detects some motion cues and chooses the search pattern that best fits to them. Specifically, a hierarchical structure of binary linear classifiers is proposed. Our experimental results show that MCS notably reduces the computational cost with respect to an state-of-the-art method while maintaining the qualityPublicad
Colección de prácticas de tratamiento digital de audio para telecomunicaciones
Grado en Ingeniería de Sistemas Audiovisuales. Asignatura: Tratamiento digital de audio para Telecomunicacione
Evaluación de mecanismos de soporte de tráfico multicast con movilidad basada en red
Con el auge actual de Internet y el incremento en el uso de dispositivos móviles ha
aumentado el consumo de contenido multimedia, del cual cabe destacar el streaming de
vídeo, el vídeo bajo demanda y la IPTV. Muchos de estos servicios hacen uso de Multicast,
un método de transmisión de datos a múltiples redes y destinatarios de manera simultánea.
Para poder realizar transmisiones de datos multicast hay direcciones IP reservadas, tanto en
IPv4 como en IPv6. El funcionamiento de multicast es muy sencillo, el host que quiere recibir
tráfico manda un mensaje a su router y se suscribe al grupo multicast (IP dentro de un rango
reservado), a partir de ahí el router ya sabe que tiene que enviar el tráfico multicast de ese
grupo a ese host en particular. El protocolo multicast en el que nos vamos a centrar es MLD
(Multicast Listener Discovery). MLD es una herramienta que utilizan los routers IPv6 para
descubrir subscriptores multicast en un enlace directo, es el equivalente a IGMP en IPv4. Se
usará la versión más reciente de este protocolo MLDv2. El objetivo final de este Trabajo Fin de Grado es evaluar estos mecanismos de envío
de tráfico multicast (MLD), en un escenario real bajo un protocolo de movilidad basado en
red (PMIPv6). Para desplegar este escenario se utilizará un prototipo con routers empleando
la distribución OpenWRT.With the current boom of Internet and the rising use of mobile devices, the media
content consumption has increased, including video streaming, video on demand and IPTV.
Many of this services use Multicast. Multicast is a method of sending IP datagrams to a
group of interested receivers in a single transmission. To do multicast data transmissions are
reserved a range of IP addresses, both in IPv4 and in IPv6. Multicast operation is simple, the
host who wants to receive traffic sends a message to its router and it subscribes to the
multicast group (IP's reserved range). Then the router knows how to send multicast traffic
for that group to that particular host. We are going to focus in the multicast protocol MLD
(Multicast Listener Discovery). MLD is tool used by IPv6 routers to discover multicast
listeners in a direct link, it is equivalent to IGMP in IPv4. We focus on the latest version of
this protocol, MLDv2. The final objective of this Bachelor Thesis is to evaluate this multicast sending
mechanisms (MLD), in a real scenario running a network-based mobility management
protocol (PMIPv6). To deploy the scenario we will utilize a prototype with routers using a
OpenWRT distribution.Ingeniería Telemátic
Laterality in Chimpanzees: Links with Behavioural Style and Social Networks
This thesis presents a series of studies investigating laterality in chimpanzees and its links with personality examined as behavioural style and social networks. The studies presented in this work were conducted by observing a group of 19 chimpanzees in captivity and present new findings in this species. However, this thesis has a broad evolutionary perspective, addressing important questions regarding personality and laterality that could prove helpful to the understanding of the evolution of laterality in vertebrates. Chapter 1 offers a general review of the three main areas of knowledge investigated: laterality, animal personality and primate social networks. Then, the first study of this project, presented in Chapter 2, began by exploring hand preference in the chimpanzee group, investigating spontaneous actions and unimanual tasks and expanding previous research by studying posture, between-task consistency and temporal stability. Chapter 3 investigated additional measures of motor laterality and proposed a novel way of measuring laterality in primates. Together, Chapters 2 and 3 directly examine laterality in chimpanzees and serve as the base from which to explore the links between laterality, personality and social networks in the subsequent studies. If lateralization is rooted in emotional processing and hemispheric lateralization, then individual differences in behaviour (particularly those that reflect emotional expression) would show a relationship with individual laterality. In order to address this question, Chapter 4 studies behavioural style in chimpanzees and its possible link with laterality. Simultaneously, if intraspecific coordination plays a role in the development of population level laterality, similarly lateralised individuals would likely have strong bonds to coordinate with each other. Chapter 5 introduces the approach and techniques of social network analysis and uses them to explore and describe the social structure of the group while describing the integration of a new adult chimpanzee. Chapter 6 applies social network analysis to explore if laterality plays a role in the way the group is structured. Lastly, Chapter 7 integrates all empirical chapters and presents the final discussion and conclusions of the thesis
Sistema de detección de caídas de personas mayores por medio de visión artificial
En torno a un 30% de la población de edad avanzada sufre al menos una caída
cada año, siendo éstas la segunda causa mundial de mortandad por lesiones accidentales
o no intencionales. Muchas de estas caídas se producen en individuos que
viven solos, en el interior de sus casas, donde no pueden ser socorridos. Además,
debido a la crisis actual y a los recortes en sanidad pública, estas personas no pueden
costearse el pago de residencias o clínicas privadas. Por otro lado, los avances
y la investigación en el campo de la visión artificial y sus aplicaciones, hacen de
esta ciencia una tecnología atractiva para ser usada en sistemas de todo tipo.
Por estas razones, este proyecto tiene como finalidad el desarrollo de un sistema
de detección de caídas para personas mayores basado en la visión artificial, que
mandará un aviso por correo electrónico cuando se detecte la caída. La aplicación
está pensada para ser usada de forma doméstica, apareciendo a un precio asequible
para el consumidor. Estará montada sobre una Raspberry Pi, y mediante el uso
de la librería OpenCV se hará el procesamiento de las imágenes. En esta memoria
se dise~nará y explicará el desarrollo del sistema.About 30% of the elderly population suffers at least one fall each year, being
these the second leading cause of death from accidental or unintentional injuries.
Many of these falls occur in individuals living alone, inside their homes, where they
can not be rescued. In addition, due to the current recession and cuts in public
health, these people can not afford to pay for residences or private clinics. On the
other hand, advances and research in the field of artificial vision and its applications
make this science, an attractive technology to be used in systems of all kinds.
Therefore, this project aims to develop a fall detection system for older people
based on artificial vision, which will send an alarm by email when the fall is
detected. The device is intended to be used in a domestic environment, having
an affordable price for the consumer. It will be mounted on a Raspberry Pi, and
OpenCV library will make the image processing. In this report, the development
of the system will be designed and explained.Ingeniería en Tecnologías Industriale
Especificación del diseño de la arquitectura para prototipo de ajedrez que permite la interacción con personas que padecen discapacidad visual
El ajedrez conocido como “el juego máximo”, es más que una herramienta de aprendizaje para el desarrollo de la mente, presentado como un juego. Aumenta la creatividad, la capacidad para resolver problemas, la habilidad de razonamiento crítico, mejora el pensamiento racional, fortalece la capacidad psicológica para aprender a controlar emociones, tener paciencia y aumentar la motivación para adquirir logros; lo cual hace que el diseño de la arquitectura para el sistema prototipo sea un pilar para eventualmente reducir la brecha que existe en las competiciones que presentan discriminación en las capacidades de los individuos. Por las cualidades del diseño de esta arquitectura se puede lograr un acercamiento de la población estudiantil sin discriminación de acceso a competiciones libres de ajedrez en donde se permitirá generar alternativas para el desarrollo cognitivo, social e interpersonal; todo mediante un plan piloto que eventualmente parte del desarrollo y la implantación del modelo prototipo en el sistema educativo. Este proyecto es la base para que a partir de su desarrollo o implementación se reduzca la diferencia existente entre un discapacitado visual y una persona sin este tipo de limitación, ofreciéndole al usuario la información necesaria para facilitar su desempeño
A Rate Control Algorthm for Low-Delay H.264 Video Coding with Stored-B Pictures
A rate control (RC) algorithm for H.264 video coding with stored-B (SB) pictures is proposed for low-delay applications. Different models for P and SB pictures are defined for a better QP and MAD estimation. Furthermore, a novel saw-tooth shaped model of target buffer level has also been introduced for a proper bit allocation in GOP structures with SB pictures. Our experimental results show that this proposal outperforms the reference software RC in terms of buffer occupancy and target bit rate adjustment at the expense of slight quality reduction.Publicad
Database of corporate bonds from Argentina
This document describes the construction of a database of corporate bonds issued by firms in Argentina between 1989 and 2005. The database draws on two main sources, the Bolsa de Comercio de Buenos Aires and the Comisión Nacional de Valores, while some additional information comes from the Mercado Abierto Electrónico. In all, we collected information on 1356 corporate bonds, though there are some bonds that have fields with missing information. Our data basically covers the characteristics of the bonds at time of issue. That is, we do not have a detailed description of how the characteristics of those corporate bonds that defaulted in 2001/2002 and were subsequently renegotiated changed. Based on the data from the primary markets, we constructed a series with the total outstanding stock of corporate bonds over this period. The information in the database allows to calculate these stocks at the firm level.primary markets, corporate bonds, institutional framework
Fatigue in Continuous Fibre Reinforced Thermoplastic Composites
International audienceAdditive manufacturing (AM) technologies have been applied with success in many applications, being fused deposition modelling (FDM) the most widely used AM technique for fabricating thermoplastic pieces. The thermoplastic parts made by FDM present lack of strength and low stiffness, as required for fully functional and load-bearing parts. Due to this restriction, a new technology to reinforce with fibres the thermoplastic filaments was developed in the last years. Continuous fibre reinforced thermoplastic composites (CFRTPC) printers are taking this technology to a whole new level in terms of efficient production and mechanical properties. Static mechanical properties, as well as fatigue behaviour, were studied since in these types of loads a wide range of engineering dynamic applications can be envisaged. Tensile tests were performed to characterise the static mechanical properties. Fatigue tests were done to analyse the durability behaviour of the FDM composite materials, and the fracture surface was analysed by SEM microscopy. The results showed that carbon fibre isotropic layers had the higher ultimate tensile stress, with 165 MPa. From fatigue tests, stress vs. number of cycles curves (S vs Nf) in the temporary life zone were obtained. It is observed from the results that specimens with nylon matrix, triangular filling pattern and matrix density of 20%, reinforced with carbon fibre at 0-degrees, showed bette
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