Initialization algorithms for wireless ad-hoc networks

The aim of this master thesis is the implementation of simulation models and the simulation of energy-efficient network initialization algorithms. First of all, it is presented a survey of state-of-the-art strategies for network initialization and exploration in wireless ad-hoc networks. Among the routing approaches presented in the survey it has been chosen the clustering-based approach due to it is the most suitable for ad-hoc sensor networks. Following are explained the features and properties of the clustering-based routing algorithms that have been selected for their implementation on this work. These implemented routing protocols are LEACH, LEACH-C, the solaraware extensions of both, HEED and a protocol based on direct transmission just as a reference in the comparison among the rest of them. On the other hand, all these routing protocols have been implemented and simulated using the OMNeT++ 4.0, which is a freeware discrete simulation environment. Subsequently, all the protocols have been simulated with different parameters and conditions to prove their functionality and to find out their behaviour in different sorts of sensor networks. Next, the simulations of the algorithms are compared among each other especially in terms of communication and energy efficiency. There are presented different comparisons such as LEACH and LEACH-C with their respective solar-aware extensions of both, a comparison between HEED with optimized parameters and non-optimized parameters, and finally a general comparison among One-hop, LEACH, LEACH-C and HEED. To sum up, some conclusions are drawn about the performance of the different protocols and some key points are given for future work. Furthermore, it is presented a brief study of the environmental impact this work may have

Les ciutats invisibles

L'autor de l'article, en la seva valoració, que estén també als altres plans del Programa de planejament territorial, assenyala que a les propostes del PTMB hi ha nombrosos "silencis" que cal entendre com les oportunitats ocultes que hauran de desenvolupar-se en un nou context social i econòmic

Conseqüències teològiques: Del Crist de la fe al Jeús de la història: La "Fides quaerens veritatem historicam"

L’Església des dels seus primers inicis tenia una regla de la fe, veritat i tradició rebuda per mitjà del baptisme. A partir d’aquesta fe s’escriviren els Evangelis i per això fou a partir de la professió del Crist de la fe que l’Església primitiva començà a narrar el Jesús de la història. D’aquí que hem de situar la recerca històrica sobre Jesús tot seguint l’axioma anselmià en aquests forma: «fides quaerens veritatem historicam», i mostrant que tal recerca històrica no té un caràcter demostratiu, sinò indicatiu en clau de «signe», com a expressió de l’encarnació intra-històrica de Jesús, el Crist, centre de la fe cristiana.The primitive Church initially had their “regula fidei” in Jesus, the Christ, and later wrote the Gospels. In this sense, they began with the profession of faith in Christ and afterwards came to know the Jesus of History. That is a reason for taking the axiom stated by Anselm: “fides quaerens veritatem historicam”, to demonstrate the priority of faith and the role of History as an expression of the intra-historical incarnation of Jesus, the Christ, who is the centre of the Christian faith

Vers una teologia de la Paraula de Déu. Reflelxions a partir del Sínode dels bisbes del 2008

A la Bíblia, en primer lloc, l’expressió paraula de Déu s’identifica amb la paraula profètica o oracle del mateix Déu que el profeta transmet fidelment. En segon lloc és la paraula que guia, instrueix i acondueix la vida del poble. La tercera accepció de la paraula de Déu qualifica al mateix Déu i a una persona humana com és Jesús. Per això una teologia de la paraula de Déu no pot limitar-se al llenguatge parlat, ja que té el seu centre en ‘la paraula feta carn que és Jesucrist. Però, quin és el significat teològic de paraula de Déu? Per la seva naturalesa, la paraula de Déu implica que en ella es faci paraula efectiva allò que nomès és possible per a Déu, la salvació plena, que és la “nova creació” i el “cel nou i terra nova”, a imatge de Jesucrist “home nou”. Per això el Sínode del 2008 rellança l’ús analògic de la paraula de Déu amb tres diversos significats: la Paraula de Déu personal que és Jescucrist; la Paraula de Déu escrita que es la Escriptura; i la Paraula de Déu transmesa que és la Tradició vivent de l’Església.In the Bible, the expression «the word of God» is first of all a prophetic word, the oracle of God himself, which the prophet faithfully transmits. Next, it is a word that guides, instructs and directs the life of the people. According to a third meaning, the word of God describes God himself and Jesus as a human being. For that reason, the theology of the word of God cannot be restricted to spoken language, since it has as its centre «the word made flesh» in Jesus Christ. What, however, is the theological meaning of the word of God? By its very nature, the word of God implies that what is possible for God alone, full salvation, is made into an effective word —a «new creation» and a «new heaven and a new earth», a «new man» in the image of Jesus. Consquently, the Synod of 2008 revived the analogical use of the word of God with three different meanings: the personal word of God, which is Jesus Christ; the written word of God, which is Scripture; and the transmitted word of God, which is the living tradition of the Church