Exploració per autor "Díaz Cort, Josep"
Ara es mostren els items 74-93 de 94
-
Parallel approximation schemes for problems on planar graphs
Díaz Cort, Josep; Serna Iglesias, María José; Torán Romero, Jacobo (1993-03)
Report de recerca
Accés obertThis paper describes a technique to obtain NC approximation schemes for the Maximum Independent Set in planar graphs and related optimization problems. -
Problems and conjectures on parameterized H-coloring
Díaz Cort, Josep; Serna Iglesias, María José; Thilikos Touloupas, Dimitrios (2002-03)
Report de recerca
Accés obert -
Random geometric problems on $[0,1]^2$
Díaz Cort, Josep; Petit Silvestre, Jordi; Serna Iglesias, María José (1998-09)
Report de recerca
Accés obertIn this paper we survey the work done for graphs on random geometric models. We present some heuristics for the problem of the Minimal Linear Arrangement on [0,1]^2 and we conclude with a collection of open problems. -
Recent developments in structural complexity
Díaz Cort, Josep; Cucker Farkas, J.F. (1988)
Report de recerca
Accés obertThis survey presents some of the recent developments in the field of structural complexity. The survey does not intend to give an exhaustive look in each one of the areas of structural complexity which have been developed ... -
Recent results on parameterized H-coloring
Díaz Cort, Josep; Serna Iglesias, María José; Thilikos Touloupas, Dimitrios (2002-03)
Report de recerca
Accés obertWe survey recent results on the complexity of several versions of the H-coloring and the list-H-coloring problems that are amenable to parameterization. -
Reconstruction of random geometric graphs: breaking the Ω(r) distortion barrier
Dani, Varsha; Díaz Cort, Josep; Hayes, Thomas P.; Moore, Cristopher (2023-10-03)
Article
Accés obertEmbedding graphs in a geographical or latent space, i.e. inferring locations for vertices in Euclidean space or on a smooth manifold or submanifold, is a common task in network analysis, statistical inference, and graph ... -
Sampling matchings in parallel
Díaz Cort, Josep; Serna Iglesias, María José; Spirakis, Paul George (1998-03)
Report de recerca
Accés obertWe present a parallel algorithm to sample matchings from an almost uniform distribution on the set of matchings of all sizes in a graph. The technique used is based on the definition of a genetic system that converges ... -
Sequential and parallel complexity of learning DFA
Balcázar Navarro, José Luis; Díaz Cort, Josep; Gavaldà, Ricard (Universitat Politècnica de Catalunya. Departament de Llenguatges i Sistemes Informàtics, 1993)
Text en actes de congrés
Accés obertIt is known that the class of deterministic finite automata is polynomial time learnable by using membership and equivalence queries. We investigate the query complexity of learning deterministic finite automata, i.e., ... -
Simulation of complicated queries by membership queries
Díaz Cort, Josep; Watanabe, Osamu (1990)
Report de recerca
Accés obertIn this paper, we consider the following type of learning: a teacher has some set, which is called a (target) concept, in his mind, and a learner tries to obtain the representation of the concept by asking queries on it ... -
Some remarks on the approximability of graph layout problems
Díaz Cort, Josep; Serna Iglesias, María José; Spirakis, Paul George (1994-03)
Report de recerca
Accés obertIn this paper we look at several well known layout problems. We show that MINCUT layout and Topological bandwidth cannot be approximated unless P=NP, whereas the Maximum linear arrangement problem can be approximated within ... -
SPALINET: Red Española de lidares de aerosoles
Guerrero Ruiz, A.; Sicard, Michaël; Rocadenbosch Burillo, Francisco; Muñoz, C.; Tomás Martínez, Sergio; Comerón Tejero, Adolfo; Pujadas, Manuel; Molero, Francisco; Alados Arboledas, Lucas; Moreno, J. M.; Bolarín, Jose Miguel; Requena, Alberto; Córdoba Jabonero, Carmen; Gil, Marisa; Exposito, Francisco Javier; Díaz Cort, Josep; Pedrós, Roberto; Martínez Lozano, José Antonio (2008)
Text en actes de congrés
Accés restringit per política de l'editorial -
Statistics on random trees
Cases Muñoz, Rafel; Díaz Cort, Josep; Martínez Parra, Conrado (1991-04-02)
Report de recerca
Accés obertIn this paper we give a survey of the symbolic operator methods to do statistics on random trees. We present some examples and apply the techniques to find their asymptotic behaviour. -
The Complexity of deciding stability under FFS in the adversarial model
Álvarez Faura, M. del Carme; Blesa Aguilera, Maria Josep; Díaz Cort, Josep; Fernández Anta, Antonio; Serna Iglesias, María José (2003-04)
Report de recerca
Accés obertIn this paper we show the polynomial time decidability of the stability property under FFS in the case that the adversary can solve ties arbitrarily. This results follows from a characterization of the stability property ... -
The Complexity of restrictive H-coloring
Díaz Cort, Josep; Serna Iglesias, María José; Thilikos Touloupas, Dimitrios (2002-03)
Report de recerca
Accés obertWe define a variant of the H-coloring problem where the number of preimages of certain vertices is predetermined as part of the problem input. We consider the decision and the counting version of the problem, namely ... -
The Hanoi's lectures
Díaz Cort, Josep (1985)
Report de recerca
Accés obertThis set of notes are the core of the lectures given at the Department of Systems theory and Optimal Control in the Institute of Computer Science and Cybernetics of Hanoi, in June of 1985. They are incomplete, and form ... -
The MINSUMCUT problem
Díaz Cort, Josep; Gibbons, Alan M.; Paterson, Michael Stewart; Torán Romero, Jacobo (1991-01)
Report de recerca
Accés obertIn this paper we first present a sequential linear algorithm for an linear arrangement problem on trees, the MINSUMCUT, and then a 0(log n) time parallel algorithm for the MINSUMCUT on trees, which uses n [super 2]/(log ... -
The multicolored graph realization problem
Díaz Cort, Josep; Yasar Diner, Oznur; Serna Iglesias, María José; Serra Albó, Oriol (Elsevier, 2022-07-01)
Article
Accés obertWe introduce the multicolored graph realization problem (MGR). The input to this problem is a colored graph (G, φ), i.e., a graph G together with a coloring φ on its vertices. We associate each colored graph (G, φ) with a ... -
The social cost of congestion games by imposing variable delays
Díaz Cort, Josep; Giotis, Ioannis; Kirousis, Lefteris; Mourtos, Ioannis; Serna Iglesias, María José (2017-12-01)
Article
Accés obertIn this study, we describe a new coordination mechanism for non-atomic congestion games that leads to a (selfish) social cost which is arbitrarily close to the non-selfish optimal. This mechanism incurs no additional cost, ... -
Theoretical aspects of graph models for MANETS
Díaz Cort, Josep; Dieter Wilhelm, Mitsche; Santi, Paolo (2010-03-01)
Report de recerca
Accés obertWe survey the main theoretical aspects of models for Mobile Ad Hoc Networks (MANETs). We present theoretical characterizations of mobile network structural properties, di erent dynamic graph models of MANETs, and nally ... -
Turing's algorithmic lens: from computability to complexity theory
Díaz Cort, Josep; Torras, Carme (2013)
Article
Accés obertThe decidability question, i.e., whether any mathematical statement could be computationally proven true or false, was raised by Hilbert and remained open until Turing answered it in the negative. Then, most efforts in ...