Fernando Soler-Toscano

FLAP Journal 2018 Journal Article

Tuning the Program Transformers from CC to PDL.

• Pere Pardo
• Enrique Sarión-Morrillo
• Fernando Soler-Toscano
• Fernando R. Velázquez-Quesada

JELIA Conference 2014 Conference Paper

Efficient Program Transformers for Translating LCC to PDL

• Pere Pardo
• Enrique Sarrión-Morillo
• Fernando Soler-Toscano
• Fernando R. Velázquez-Quesada

Abstract This work proposes an alternative definition of the so-called program transformers, used to obtain reduction axioms in the Logic of Communication and Change. Our proposal uses an elegant matrix treatment of Brzozowski’s equational method instead of Kleene’s translation from finite automata to regular expressions. The two alternatives are shown to be equivalent, with Brzozowski’s method having the advantage of being computationally more efficient.

TCS Journal 2013 Journal Article

A colouring protocol for the generalized Russian cards problem

• Andrés Cordón-Franco
• Hans van Ditmarsch
• David Fernández-Duque
• Fernando Soler-Toscano

In the generalized Russian cards problem, Alice, Bob and Cath draw a, b and c cards, respectively, from a deck of size a + b + c. Alice and Bob must then communicate their entire hand to each other, without Cath learning the owner of a single card she does not hold. Unlike many traditional problems in cryptography, however, they are not allowed to encode or hide the messages they exchange from Cath. The problem is then to find methods through which they can achieve this. We propose a general four-step solution based on finite vector spaces, and call it the “colouring protocol”, as it involves colourings of lines. Our main results show that the colouring protocol may be used to solve the generalized Russian cards problem in cases where a is a power of a prime, c = O ( a 2 ) and b = O ( c 2 ). This improves substantially on the set of parameters for which solutions are known to exist; in particular, it had not been shown previously that the problem could be solved in cases where the eavesdropper has more cards than one of the communicating players.

JELIA Conference 2006 Conference Paper

: Tableaux and Resolution for Finite Abduction

• Fernando Soler-Toscano
• Ángel Nepomuceno-Fernández

Abstract n -tableaux [1] and δ -resolution [2], which are based, respectively, on semantic tableaux and resolution, have been properly used for the resolution of abductive problems. The tool we present is a Prolog implementation of an abductive solver which combines both calculi to attack first order abductive problems by reducing them to finite versions, that is, propositional rewritings of the problems which presuppose a context representable with finite models with a known cardinality.