Factoid question answering for spoken documents 

Comas Umbert, Pere R. (Date of defense: 2012-05-12)

In this dissertation, we present a factoid question answering system, specifically tailored for Question Answering (QA) on spoken documents. This work explores, for the first time, which techniques can be robustly adapted ...

Fast photorealistic techniques to simulate global illumination in videogames and virtual environments 

Méndez Feliu, Àlex (Date of defense: 2007-06-15)

Per al càlcul de la il·luminació global per a la síntesi d'imatges d'escenaris virtuals s'usen mètodes físicament acurats com a radiositat o el ray-tracing. Aquests mètodes són molt potents i capaços de generar imatges de ...

From the i* diversity to a common interoperability framework 

Cares Gallardo, Carlos (Date of defense: 2012-09-20)

Since the i* framework emerged in the requirements engineering community in the mid-90s, different research groups have proposed variations to the modelling language proposed in the i* framework (¿the i* language¿). There ...

Generative manifold learning for the exploration of partially labeled data 

Cruz Barbosa, Raúl (Date of defense: 2009-10-01)

In many real-world application problems, the availability of data labels for supervised learning is rather limited. Incompletely labeled datasets are common in many of the databases generated in some of the currently most ...

Geometric constraint solving in a dynamic geometry framework. 

Hidalgo García, Marta R. (Date of defense: 2013-12-02)

Geometric constraint solving is a central topic in many fields such as parametric solid modeling, computer-aided design or chemical molecular docking. A geometric constraint problem consists of a set geometric objects on ...

Global illumination techniques for the computation of hight quality images in general environments 

Pérez Cazorla, Frederic (Date of defense: 2003-05-26)

The objective of this thesis is the development of algorithms for the simulation of the light transport in general environments to render high quality still images. To this end, first we have analyzed the existing methods ...

Heterogeneous neural networks: theory and applications 

Belanche Muñoz, Lluís A. (Lluís Antoni) (Date of defense: 2000-07-18)

Aquest treball presenta una classe de funcions que serveixen de models neuronals generalitzats per ser usats en xarxes neuronals artificials. Es defineixen com una mesura de similitud que actúa com una definició flexible ...

Information theoretic refinement criteria for image synthesis 

Rigau Vilalta, Jaume (Date of defense: 2006-11-17)

Aquest treball està enmarcat en el context de gràfics per computador partint de la intersecció de tres camps: rendering, teoria de la informació, i complexitat.<br/><br/>Inicialment, el concepte de complexitat d'una escena ...

Learning finite-state machines: statistical and algorithmic aspects 

Balle Pigem, Borja de (Date of defense: 2013-07-12)

The present thesis addresses several machine learning problems on generative and predictive models on sequential data. All the models considered have in common that they can be de ned in terms of nite-state machines. On ...

Learning with Feed-forward Neural Networks: Three Schemes to Deal with the Bias/Variance Trade-off 

Romero Merino, Enrique (Date of defense: 2004-11-30)

In terms of the Bias/Variance decomposition, very flexible (i.e., complex) Supervised Machine Learning systems may lead to unbiased estimators but with high variance. A rigid model, in contrast, may lead to small variance ...

Lightweight and static verification of UML executable models 

Planas Hortal, Elena (Date of defense: 2013-03-21)

Executable models play a key role in many development methods (such as MDD and MDA) by facilitating the immediate simulation/implementation of the software system under development. This is possible because executable ...

Meta-alignment of biological sequences 

Blanco García, Enrique (Date of defense: 2006-07-21)

Les seqüències són una de les estructures de dades més versàtils que existeixen. De forma relativament senzilla, en una seqüència de símbols es pot emmagatzemar informació de qualsevol tipus. L'anàlisi sistemàtic de ...

Modelling rational inquiry in non-ideal agents 

Moreno Ribas, Antonio (Date of defense: 2000-12-18)

de la tesi doctoral<br/><br/>L'objectiu principal del treball realitzat ha sigut el desenvolupar una manera de modelar el procés d'investigació racional (l'evolució de les creences d'un agent racional com a conseqüència ...

Multi-objective optimization in graphical models 

Rollón, Emma (Date of defense: 2008-11-03)

Many real-life optimization problems are combinatorial, i.e. they concern a choice of the best solution from a finite but exponentially large set of alternatives. Besides, the solution quality of many of these problems ...

Non-functional requirements as drivers of software architecture design 

Ameller, David (Date of defense: 2014-01-23)

In the last decades, software engineering has become an important area of research. As researchers, we try to identify a problem, a need, or a hole in some research topic, once identified we make an effort to produce new ...

On Collective Computation 

Delgado Pin, Jordi (Date of defense: 1997-12-05)

On the complexity of resolution-based proof systems 

Oliva Valls, Sergi (Date of defense: 2013-05-02)

Propositional Proof Complexity is the area of Computational Complexity that studies the length of proofs in propositional logic. One of its main questions is to determine which particular propositional formulas have short ...

On the design and implementation of flexible software platforms to facilitate the development of advanced graphics applications 

Fairen Gonzalez, Marta (Date of defense: 2000-11-23)

This thesis presents the design and implementation of a software development platform (ATLAS) which offers some tools and methods to greatly simplify the construction of fairly sophisticated applications. It allows thus ...

On the intelligent management of sepsis in the intensive care unit 

Ribas Ripoll, Vicent Jordi (Date of defense: 2013-01-29)

The management of the Intensive Care Unit (ICU) in a hospital has its own, very specific requirements that involve, amongst others, issues of risk-adjusted mortality and average length of stay; nurse turnover and communication ...

OntoWEDSS - An Ontology-based Environmental Decision-Support System for the management of Wastewater treatment plants 

Ceccaroni, Luigi (Date of defense: 2001-12-21)

Les contribucions d'aquesta tesi uneixen dues disciplines: ciències ambientals (específicament, gestió d'aigües residuals) i informàtica (específicament, intel·ligència artificial). El tractament d'aigües residuals com a ...