A proposal for the diagnosis of uncertain dynamic systems based on interval models

The performance of a model-based diagnosis system could be affected by several uncertainty sources, such as,model errors,uncertainty in measurements, and disturbances. This uncertainty can be handled by mean of interval models.The aim of this thesis is to propose a methodology for fault detection, isolation and identification based on interval models. The methodology includes some algorithms to obtain in an automatic way the symbolic expression of the residual generators enhancing the structural isolability of the faults, in order to design the fault detection tests. These algorithms are based on the structural model of the system. The stages of fault detection, isolation, and identification are stated as constraint satisfaction problems in continuous domains and solved by means of interval based consistency techniques. The qualitative fault isolation is enhanced by a reasoning in which the signs of the symptoms are derived from analytical redundancy relations or bond graph models of the system. An initial and empirical analysis regarding the differences between interval-based and statistical-based techniques is presented in this thesis. The performance and efficiency of the contributions are illustrated through several application examples, covering different levels of complexity.

Paisatge i models urbans contemporanis. Les comarques gironines (1979-2006): del "desarrollismo" a la globalització

This doctoral thesis offers a quantitative and qualitative analysis of the changes in the urban shape and landscape of the Girona Counties between 1979 and 2006. The theoretical part of the research lies within the framework of the dispersed city phenomenon, and is based on the hypothesis of convergence towards a global urban model. The empirical part demonstrates this proposition with a study of 522 zone development plans in the Girona Counties. The results point to the consolidation of the dispersed city phenomenon, as shown by the sudden increase in built-up space, the spread of urban development throughout the territory, and the emergence of a new, increasingly generic landscape comprising three major morphological types: urban extensions, low density residential estates and industrial zones. This reveals shortcomings of planning for urban growth, weakening of the city as a public project, and a certain degradation of the Mediterranean city model.

L'evolució dels models de turisme litoral: el Regne Unit, la Costa brava i Cuba

La tesi es centra en una anàlisi prèvia de les implicacions de la teoria del cicle de vida aplicada a les destinacions turístiques pel geògraf canadenc Richard W. Butler (1982) i en un estudi del significat de l'aparició del postmodernisme i les seves repercussions en el turisme, a la vegada que es resegueix la història que ha fet possible l'aparició del turisme massificat de sol i platja. Tot això és la base teòrica imprescindible per poder estudiar empíricament les destinacions de Saltburn (Regne Unit), l'Estartit (Costa Brava) i Cayo Coco (Cuba), utilitzant el cicle de vida per escriure la seva història i veure les polítiques de desenvolupament i regeneració turística que s'han seguit i si aquestes es poden qualificar de postfordistes. La principal conclusió és que el concepte del cicle de vida es limita a ser una eina de diagnòstic a posteriori. El cicle de vida, com a instrument prescriptiu, no serveix. Es específic per a cada destinació, amb unes etapes i punts d'inflexió que només es poden establir en restrospectiva. El cicle de vida és una eina descriptiva molt útil per entendre l'evolució de les destinacions turístiques i els seus mercats, però vigilant de no caure en falses exploracions o perillosos determinismes.