http://hdl.handle.net/2117/3092 Sat, 18 May 2013 12:53:03 GMT 2013-05-18T12:53:03Z webmaster.bupc@upc.edu Universitat Politècnica de Catalunya. Servei de Biblioteques i Documentació no http://hdl.handle.net/2117/19310 Title: Cloud virtual machine scheduling: modelling the cloud virtual machine instantiation Authors: Sotiriadis, S.; Bessis, N.; Xhafa Xhafa, Fatos; Antonopoulos, Nicos Thu, 16 May 2013 13:55:24 GMT http://hdl.handle.net/2117/19310 2013-05-16T13:55:24Z Sotiriadis, S.; Bessis, N.; Xhafa Xhafa, Fatos; Antonopoulos, Nicos no Cloud, Static and dynamic virtual machine scheduling, Virtual machine instantiation, Virtualization http://hdl.handle.net/2117/19306 Title: Performance analysis of DSR and DYMO routing protocols for VANETs Authors: Spaho, Evjola; Ikeda, Makoto; Barolli, Leonard; Xhafa Xhafa, Fatos; Kolici, Vladi; Takizawa, Makoto Thu, 16 May 2013 13:36:45 GMT http://hdl.handle.net/2117/19306 2013-05-16T13:36:45Z Spaho, Evjola; Ikeda, Makoto; Barolli, Leonard; Xhafa Xhafa, Fatos; Kolici, Vladi; Takizawa, Makoto no DSR, DYMO, Routing protocols, VANETs http://hdl.handle.net/2117/19304 Title: Performance evaluation of WMN-GA system for low densities of clients and different settings of population size Authors: Oda, Tetsuya; Barolli, Admir; Spaho, Evjola; Barolli, Leonard; Xhafa Xhafa, Fatos; Takizawa, Makoto Thu, 16 May 2013 13:22:36 GMT http://hdl.handle.net/2117/19304 2013-05-16T13:22:36Z Oda, Tetsuya; Barolli, Admir; Spaho, Evjola; Barolli, Leonard; Xhafa Xhafa, Fatos; Takizawa, Makoto no Genetic algorithms, Number of covered users, Population size, Size of giant component, Wireless Mesh Networks http://hdl.handle.net/2117/19301 Title: Multimedia transmissions over a MANET testbed: problems and issues Authors: Kulla, E.; Ikeda, Makoto; Oda, Tetsuya; Barolli, Leonard; Xhafa Xhafa, Fatos; Takizawa, Makoto Thu, 16 May 2013 13:12:58 GMT http://hdl.handle.net/2117/19301 2013-05-16T13:12:58Z Kulla, E.; Ikeda, Makoto; Oda, Tetsuya; Barolli, Leonard; Xhafa Xhafa, Fatos; Takizawa, Makoto no Audio, BATMAN, MANET testbed, Multimedia transmissions, Problems and issues, Video http://hdl.handle.net/2117/19300 Title: Data replication and synchronization in P2P collaborative systems Authors: Xhafa Xhafa, Fatos Thu, 16 May 2013 13:04:29 GMT http://hdl.handle.net/2117/19300 2013-05-16T13:04:29Z Xhafa Xhafa, Fatos no Data replication, data synchronization, P2P systems, groupware http://hdl.handle.net/2117/19264 Title: A comparison study between two fuzzy-based trustworthiness systems for P2P networks Authors: Umezaki, K.; Spaho, Evjola; Barolli, Leonard; Xhafa Xhafa, Fatos; Matsuo, Keita; Iwashige, J. Wed, 15 May 2013 15:47:19 GMT http://hdl.handle.net/2117/19264 2013-05-15T15:47:19Z Umezaki, K.; Spaho, Evjola; Barolli, Leonard; Xhafa Xhafa, Fatos; Matsuo, Keita; Iwashige, J. no Fuzzy system, JXTA-Overlay, P2P, Trustworthiness http://hdl.handle.net/2117/19263 Title: Tuning of operators in memetic algorithms for independent batch scheduling in computational grids Authors: Xhafa Xhafa, Fatos; Duran, B.; Barolli, Leonard; Kolici, Vladi; Miho, Rozeta; Takizawa, Makoto Wed, 15 May 2013 15:34:03 GMT http://hdl.handle.net/2117/19263 2013-05-15T15:34:03Z Xhafa Xhafa, Fatos; Duran, B.; Barolli, Leonard; Kolici, Vladi; Miho, Rozeta; Takizawa, Makoto no Computational Grids, Memetic Algorithms, Meta-heuristics, Operators, Tuning http://hdl.handle.net/2117/19260 Title: Mission operations scheduling: complexity and resolution methods Authors: Xhafa Xhafa, Fatos; Sun, Junzi; Barolli, Admir; Takizawa, Makoto Wed, 15 May 2013 15:05:24 GMT http://hdl.handle.net/2117/19260 2013-05-15T15:05:24Z Xhafa Xhafa, Fatos; Sun, Junzi; Barolli, Admir; Takizawa, Makoto no Constraint programming, Genetic Algorithms, Ground station scheduling, Satellite scheduling, Simulation http://hdl.handle.net/2117/19259 Title: A fuzzy-based cluster-head selection system for WSNs: a comparison study for static and mobile sensors Authors: Barolli, Leonard; Wang, Qi; Kulla, E.; Xhafa Xhafa, Fatos; Kamo, B.; Takizawa, Makoto Wed, 15 May 2013 14:48:08 GMT http://hdl.handle.net/2117/19259 2013-05-15T14:48:08Z Barolli, Leonard; Wang, Qi; Kulla, E.; Xhafa Xhafa, Fatos; Kamo, B.; Takizawa, Makoto no http://hdl.handle.net/2117/19258 Title: Performance evaluation of WMN-GA system for dense networks considering different distributions Authors: Barolli, Admir; Oda, Tetsuya; Barolli, Leonard; Xhafa Xhafa, Fatos; Takizawa, Makoto; Uchida, K. Wed, 15 May 2013 14:28:58 GMT http://hdl.handle.net/2117/19258 2013-05-15T14:28:58Z Barolli, Admir; Oda, Tetsuya; Barolli, Leonard; Xhafa Xhafa, Fatos; Takizawa, Makoto; Uchida, K. no Crossover operators, Genetic algorithms, Mutation operators, Size of giant component, Wireless mesh networks http://hdl.handle.net/2117/19252 Title: The HOM problem is EXPTIME-complete Authors: Creus López, Carles; Gascón Caro, Adrià; Godoy Balil, Guillem; Ramos, Lander Abstract: The HOM problem questions whether the image of a given regular tree language through a given tree homomorphism is also regular. Decidability of HOM is an important theoretical question which was open for a long time. Recently, HOM has been proved decidable with a triple exponential time algorithm. In this paper we obtain an exponential time algorithm for this problem, and conclude that it is EXPTIME-complete. The proof builds upon previous results and techniques on tree automata with constraints. Wed, 15 May 2013 13:39:05 GMT http://hdl.handle.net/2117/19252 2013-05-15T13:39:05Z Creus López, Carles; Gascón Caro, Adrià; Godoy Balil, Guillem; Ramos, Lander no Decision Problems, Tree Automata, Tree Homomorphisms The HOM problem questions whether the image of a given regular tree language through a given tree homomorphism is also regular. Decidability of HOM is an important theoretical question which was open for a long time. Recently, HOM has been proved decidable with a triple exponential time algorithm. In this paper we obtain an exponential time algorithm for this problem, and conclude that it is EXPTIME-complete. The proof builds upon previous results and techniques on tree automata with constraints. http://hdl.handle.net/2117/19207 Title: Performance of OLSR and DSDV protocols in a VANET scenario: evaluation using CAVENET and NS3 Authors: Spaho, Evjola; Ikeda, Makoto; Barolli, Leonard; Xhafa Xhafa, Fatos; Younas, Muhammad; Takizawa, Makoto Tue, 14 May 2013 12:40:30 GMT http://hdl.handle.net/2117/19207 2013-05-14T12:40:30Z Spaho, Evjola; Ikeda, Makoto; Barolli, Leonard; Xhafa Xhafa, Fatos; Younas, Muhammad; Takizawa, Makoto no DSDV, OLSR, Routing Protocols, VANETs http://hdl.handle.net/2117/19138 Title: An integrated fuzzy-based trustworthiness system for P2P communications in JXTA-overlay Authors: Umezaki, K.; Spaho, Evjola; Barolli, Leonard; Xhafa Xhafa, Fatos; Younas, Muhammad; Iwashige, J. Wed, 08 May 2013 14:17:38 GMT http://hdl.handle.net/2117/19138 2013-05-08T14:17:38Z Umezaki, K.; Spaho, Evjola; Barolli, Leonard; Xhafa Xhafa, Fatos; Younas, Muhammad; Iwashige, J. no Fuzzy System, JXTA-Overlay, P2P, Trustworthiness http://hdl.handle.net/2117/18911 Title: Ant colony optimization theory : a survey Authors: Dorigo, Marco; Blum, Christian Abstract: Research on a new metaheuristic for optimization is often initially focused on proof-of-concept applications. It is only after experimental work has shown the practical interest of the method that researchers try to deepen their understanding of the method's functioning not only through more and more sophisticated experiments but also by means of an effort to build a theory. Tackling questions such as "how and why the method works" is important, because finding an answer may help in improving its applicability. Ant colony optimization, which was introduced in the early 1990s as a novel technique for solving hard combinatorial optimization problems, finds itself currently at this point of its life cycle. With this article we provide a survey on theoretical results on ant colony optimization. First, we review some convergence results. Then we discuss relations between ant colony optimization algorithms and other approximate methods for optimization. Finally, we focus on some research efforts directed at gaining a deeper understanding of the behavior of ant colony optimization algorithms. Throughout the paper we identify some open questions with a certain interest of being solved in the near future. Description: "Theoretical Computer Science Top Cited Article 2005-2010" Mon, 22 Apr 2013 10:09:40 GMT http://hdl.handle.net/2117/18911 2013-04-22T10:09:40Z Dorigo, Marco; Blum, Christian no Ant colony optimization, Metaheuristics, Combinatorial optimization, Convergence, Stochastic gradient descent, Model-based search, Approximate algorithms Research on a new metaheuristic for optimization is often initially focused on proof-of-concept applications. It is only after experimental work has shown the practical interest of the method that researchers try to deepen their understanding of the method's functioning not only through more and more sophisticated experiments but also by means of an effort to build a theory. Tackling questions such as "how and why the method works" is important, because finding an answer may help in improving its applicability. Ant colony optimization, which was introduced in the early 1990s as a novel technique for solving hard combinatorial optimization problems, finds itself currently at this point of its life cycle. With this article we provide a survey on theoretical results on ant colony optimization. First, we review some convergence results. Then we discuss relations between ant colony optimization algorithms and other approximate methods for optimization. Finally, we focus on some research efforts directed at gaining a deeper understanding of the behavior of ant colony optimization algorithms. Throughout the paper we identify some open questions with a certain interest of being solved in the near future. http://hdl.handle.net/2117/18900 Title: Impact of population size and number of generations on the performance of dense WMNs Authors: Barolli, A.; Oda, Tetsuya; Spaho, Evjola; Barolli, Leonard; Xhafa Xhafa, Fatos; Takizawa, Makoto Fri, 19 Apr 2013 13:43:17 GMT http://hdl.handle.net/2117/18900 2013-04-19T13:43:17Z Barolli, A.; Oda, Tetsuya; Spaho, Evjola; Barolli, Leonard; Xhafa Xhafa, Fatos; Takizawa, Makoto no Genetic Algorithms, Number of Generations, Population Size, Wireless Mesh Networks