Search results for "COMU"
showing 10 items of 4977 documents
Resource sharing optimality in WiFi infrastructure networks
2009
In WiFi networks, mobile nodes compete for accessing a shared channel by means of a random access protocol called Distributed Coordination Function (DCF). Although this protocol is in principle fair, since all the stations have the same probability to transmit on the channel, it has been shown that unfair behaviors may emerge in actual networking scenarios. Assuming that a contending node can dynamically change its strategy, by tuning its contention parameters to non-standard values on the basis of channel observations, we prove that, for infrastructure networks with bidirectional traffic and homogeneous application requirements, selfish access strategies are able to reach equilibrium condi…
Performance analysis of selfish access strategies on WiFi infrastructure networks
2009
In this paper we propose a game-theoretic approach for characterizing WiFi network performance in presence of intelligent nodes employing cognitive functionalities. We assume that a cognitive WiFi node is aware of its application requirements and is able to dynamically estimate the network status, in order to dynamically change its access strategy by tuning the contention window settings. We prove that, for infrastructure networks with bidirectional traffic and homogeneous application requirements, selfish access strategies are able to reach equilibrium conditions, which are also Pareto optimal. Indeed, we show that the station strategies converge toward values which maximize a per-node uti…
Peer to Peer Equation Augmentation for an Altitude Aided GNSS Receiver
2010
This paper considers the possibility to integrate external altitude measurements with a Kalman based Global Navigation Satellite System (GNSS) receiver in a peer to peer scenario. The performance of such a system is investigated for different characteristics of the aiding measurement and for different degree of trust of the receiver upon the aiding measurement. The aiding measurement is obtained starting from the altitude measurements that the other peers in the network send to the aided user. The experiments highlight the need for a parameter that points out the effectiveness and the consistency of the computed aiding measurement. To this purpose, a reliability index is proposed, on the ba…
The Information and Communication Technologies in the school sys-tem. A review of the research lines
2005
This paper offers a classification of research trends and perspectives about processes oriented to incorporate information and communication technologies (ICT) in schools. Identified are four research trends: a) studies about indicators of computers quantity in school systems; b) studies about computer effects in learning; c) studies about opinion, perspectives and attitudes of educational agents to ICT; and d) studies about computers' educational use in classroom and colleges. This paper finishes with a synthesis of current knowledge about projects and programs intended for the embodiment of ICT in school systems.
I limiti della legittimazione attiva dei consiglieri comunali e l’abolizione dei controlli preventivi sugli atti degli enti locali (nota a CONSIGLIO …
2007
I limiti della legittimazione attiva dei consiglieri comunali e l’abolizione dei controlli preventivi sugli atti degli enti locali (nota a CONSIGLIO DI STATO, SEZ. V - sentenza 19 febbraio 2007 n. 826).
Tecnologías fotónicas y comunicaciones ópticas
1997
El presente trabajo tiene por objeto presentar una visión de las tecnologías fotónicas orientada fundamentalmente a su aplicación en telecomunicaciones.
Provincia de Albacete
Llegenda. - Relleu representat per corbes de nivell Ed. Especial de juny de 1938 del mapa editat pel Ministerio de Obras Públicas el 1935
Mapa-itinerario del antiguo Reino de Valencia
A la part superior del mapa: escut del Regne de València Localització per quadrícules numerades. - Conté informació de les xarxes de comunicació. - Relació dels municipis indicant la distància a la partida, a la capital i a Madrid
Provincia de Valencia
Llegenda. - Relleu representat per corbes de nivell. - Representació dels fars Edició especial d'agost de 1938 del mapa editat pel Ministerio de Obras Públicas el 1935