Um ambiente computacional para emular em rede aplicações interativas desenvolvidas para televisão digital

Pós-graduação em Televisão Digital: Informação e Conhecimento - FAAC

Detecção de anomalias por Floresta Caminhos Ótimos

Pós-graduação em Ciência da Computação - IBILCE

Modelo de simulação NS-2 para o protocolo DNP3 sobre o protocolo de rede sem fio IEEE 802.15.4 para simulação de baixo custo de aplicação smart grid

Pós-graduação em Engenharia Elétrica - FEIS

Desempenho do RTK em rede sob efeito da cintilação ionosférica

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Simulação de um sistema de reputação centralizado para VANETs

Pós-graduação em Ciência da Computação - IBILCE

Interconexión de centros de datos mediante técnicas SDN

En este trabajo final de grado se ha contribuido a la interconexión de centros de datos distribuidos geográficamente, integrando para ello nuevas funcionalidades en la arquitectura Application-Based Network Operations (ABNO) y configurando los componentes software necesarios. ABNO engloba distintas tecnologías que recogen la información sobre los recursos disponibles en la red con el objetivo de proporcionar rutas específicas para el tráfico. La solución que se presenta en este trabajo se basa en las redes definidas por software (Software-Defined Networking, SDN), como solución innovadora para mejorar la gestión y el control de las infraestructuras que pertenecen a múltiples dominios administrativos, pero trabajan en colaboración en una federación común mejorando la calidad del servicio ofrecido. La conectividad entre los diferentes dominios es posible gracias a los Túneles GRE. Cada centro de datos supone un dominio administrativo diferenciado, disponiendo cada uno de ellos del software de gestión en la nube OpenStack para la creación de las máquinas virtuales (VM) que posteriormente serán interconectadas. Además, cada centro de datos también contará con el controlador Ryu SDN que se encargará del control de la conectividad, siendo también independiente para cada uno de estos dominios. Con el objetivo de mantener una visión integral de todos los recursos de la red disponibles, y de proporcionar una conectividad extremo a extremo (E2E) requerida por los centros de datos, la arquitectura ABNO ha tenido que ser modificada para soportar estas nuevas funcionalidades, así como validada en un escenario con infraestructuras multidominio.

REFLEXOS INDIVIDUAIS DO USO PESSOAL E EXCESSIVO DE COMUNICADORES INSTANTÂNEOS NO AMBIENTE DE TRABALHO

A Internet está inserida no cotidiano do indivíduo, e torna-se cada vez mais acessível por meio de diferentes tipos de dispositivos. Com isto, diversos estudos foram realizados com o intuito de avaliar os reflexos do seu uso excessivo na vida pessoal, acadêmica e profissional. Esta dissertação buscou identificar se a perda de concentração e o isolamento social são alguns dos reflexos individuais que o uso pessoal e excessivo de aplicativos de comunicação instantânea podem resultar no ambiente de trabalho. Entre as variáveis selecionadas para avaliar os aspectos do uso excessivo de comunicadores instantâneos tem-se a distração digital, o controle reduzido de impulso, o conforto social e a solidão. Através de uma abordagem de investigação quantitativa, utilizaram-se escalas aplicadas a uma amostra de 283 pessoas. Os dados foram analisados por meio de técnicas estatísticas multivariadas como a Análise Fatorial Exploratória e para auferir a relação entre as variáveis, a Regressão Linear Múltipla. Os resultados deste estudo confirmam que o uso excessivo de comunicadores instantâneos está positivamente relacionado com a perda de concentração, e a variável distração digital exerce uma influência maior do que o controle reduzido de impulso. De acordo com os resultados, não se podem afirmar que a solidão e o conforto social exercem relações com aumento do isolamento social, devido à ausência do relacionamento entre os construtos.

Orchestration of energy efficiency capabilities for a sustainable network management

The energy demand for operating Information and Communication Technology (ICT) systems has been growing, implying in high operational costs and consequent increase of carbon emissions. Both in datacenters and telecom infrastructures, the networks represent a significant amount of energy spending. Given that, there is an increased demand for energy eficiency solutions, and several capabilities to save energy have been proposed. However, it is very dificult to orchestrate such energy eficiency capabilities, i.e., coordinate or combine them in the same network, ensuring a conflict-free operation and choosing the best one for a given scenario, ensuring that a capability not suited to the current bandwidth utilization will not be applied and lead to congestion or packet loss. Also, there is no way in the literature to do this taking business directives into account. In this regard, a method able to orchestrate diferent energy eficiency capabilities is proposed considering the possible combinations and conflicts among them, as well as the best option for a given bandwidth utilization and network characteristics. In the proposed method, the business policies specified in a high-level interface are refined down to the network level in order to bring highlevel directives into the operation, and a Utility Function is used to combine energy eficiency and performance requirements. A Decision Tree able to determine what to do in each scenario is deployed in a Software Defined Network environment. The proposed method was validated with diferent experiments, testing the Utility Function, checking the extra savings when combining several capabilities, the decision tree interpolation and dynamicity aspects. The orchestration proved to be valid to solve the problem of finding the best combination for a given scenario, achieving additional savings due to the combination, besides ensuring a conflict-free operation.

Sistema de climatización por suelo radiante coalimentado por energías renovables

Se presenta el sistema de climatización basado en suelo radiante coalimentado por fuentes de energía renovables, que es capaz de proporcionar calor o frío. Se ha modelado una instalación genérica, que ha sido particularizada e integrada en una vivienda-laboratorio de unos 54m2. El sistema está compuesto por placas termo-solares, calentador eléctrico, bomba de calor aire-agua, acumuladores, circuito de suelo radiante y fancoil. El sistema de control está basado en un autómata que integra sensores y actuadores de diversas tecnologías que permiten monitorizar el sistema, visualizar y gestionar la instalación de forma remota y realizar un control minimizando el gasto energético. El sistema de control es reactivo en tiempo real por lo que cada vez que sucede algún cambio en el entorno se desencadenas las acciones oportunas.

Representation of 2D objects with a topology preserving network

Comunicación presentada en el 2nd International Workshop on Pattern Recognition in Information Systems, Alicante, April, 2002.

Hand gesture recognition based on morphologic features

Comunicación presentada en el IX Simposium Nacional de Reconocimiento de Formas y Análisis de Imágenes, Benicàssim, Mayo, 2001.

An evolutive approach for the delineation of local labour markets

This paper presents a new approach to the delineation of local labour markets based on evolutionary computation. The main objective is the regionalisation of a given territory into functional regions based on commuting flows. According to the relevant literature, such regions are defined so that (a) their boundaries are rarely crossed in daily journeys to work, and (b) a high degree of intra-area movement exists. This proposal merges municipalities into functional regions by maximizing a fitness function that measures aggregate intra-region interaction under constraints of inter-region separation and minimum size. Real results are presented based on the latest database from the Census of Population in the Region of Valencia. Comparison between the results obtained through the official method which currently is most widely used (that of British Travel-to-Work Areas) and those from our approach is also presented, showing important improvements in terms of both the number of different market areas identified that meet the statistical criteria and the degree of aggregate intra-market interaction.

An evolutionary approach to the delineation of functional areas based on travel-to-work flows

This paper presents a new approach to the delineation of local labor markets based on evolutionary computation. The aim of the exercise is the division of a given territory into functional regions based on travel-to-work flows. Such regions are defined so that a high degree of inter-regional separation and of intra-regional integration in both cases in terms of commuting flows is guaranteed. Additional requirements include the absence of overlap between delineated regions and the exhaustive coverage of the whole territory. The procedure is based on the maximization of a fitness function that measures aggregate intra-region interaction under constraints of inter-region separation and minimum size. In the experimentation stage, two variations of the fitness function are used, and the process is also applied as a final stage for the optimization of the results from one of the most successful existing methods, which are used by the British authorities for the delineation of travel-to-work areas (TTWAs). The empirical exercise is conducted using real data for a sufficiently large territory that is considered to be representative given the density and variety of travel-to-work patterns that it embraces. The paper includes the quantitative comparison with alternative traditional methods, the assessment of the performance of the set of operators which has been specifically designed to handle the regionalization problem and the evaluation of the convergence process. The robustness of the solutions, something crucial in a research and policy-making context, is also discussed in the paper.

A memetic algorithm for the delineation of local labour markets

Given a territory composed of basic geographical units, the delineation of local labour market areas (LLMAs) can be seen as a problem in which those units are grouped subject to multiple constraints. In previous research, standard genetic algorithms were not able to find valid solutions, and a specific evolutionary algorithm was developed. The inclusion of multiple ad hoc operators allowed the algorithm to find better solutions than those of a widely-used greedy method. However, the percentage of invalid solutions was still very high. In this paper we improve that evolutionary algorithm through the inclusion of (i) a reparation process, that allows every invalid individual to fulfil the constraints and contribute to the evolution, and (ii) a hillclimbing optimisation procedure for each generated individual by means of an appropriate reassignment of some of its constituent units. We compare the results of both techniques against the previous results and a greedy method.

Los mercados locales de trabajo españoles: una aplicación del nuevo procedimiento británico

Este trabajo se ha realizado en el marco del proyecto SEJ2007-67767-C04-02, financiado por el Ministerio de Ciencia e Innovación y FEDER.