Fundamenta Informaticae - Volume 69, issue 4

Authors: Ciucci, Davide

Article Type: Research Article

Abstract: Several residuated algebras are taken into account. The set of axioms defining each structure is reduced with the aim to obtain an independent axiomatization. Further, the relationship among all the algebras is studied and their dependencies outlined. Finally, rough approximation spaces are introduced in residuated lattices with involution and their algebraic structure outlined.

Citation: Fundamenta Informaticae, vol. 69, no. 4, pp. 359-387, 2006

Authors: Esposito, Floriana | Fanizzi, Nicola | Ferilli, Stefano | Basile, Teresa M.A. | Di Mauro, Nicola

Article Type: Research Article

Abstract: Traditional Machine Learning approaches based on single inference mechanisms have reached their limits. This causes the need for a framework that integrates approaches based on abduction and abstraction capabilities in the inductive learning paradigm, in the light of Michalski's Inferential Theory of Learning (ITL). This work is intended as a survey of the most significant contributions that are present in the literature, concerning single reasoning strategies and practical ways for bringing them together and making …them cooperate in order to improve the effectiveness and efficiency of the learning process. The elicited role of an abductive proof procedure is tackling the problem of incomplete relevance in the incoming examples. Moreover, the employment of abstraction operators based on (direct and inverse) resolution to reduce the complexity of the learning problem is discussed. Lastly, a case study that implements the combined framework into a real multistrategy learning system is briefly presented. Show more

Keywords: Inductive Learning, Abstraction, Abduction, Multistrategy Learning

Citation: Fundamenta Informaticae, vol. 69, no. 4, pp. 389-409, 2006

Authors: Pomykała, Jacek | Barabasz, Sławomir

Article Type: Research Article

Abstract: In the article we present a new (t,n) threshold proxy signature scheme with known signers. It is based on the elliptic curve cryptosystem whose security refers to the discrete logarithm problem (DLP) in the group E(E_p ) of rational points of elliptic curve over the finite field. In comparision to similar schemes based on the RSA or DSS systems our solution requires application of significantly shorter cryptographic keys. The scheme is relatively simple in construction, …has the property of unforgeability, non-repudation and admits the proactive security. Show more

Keywords: group of rational points of elliptic curve, secret sharing, discrete logarithm problem, digital signature

Citation: Fundamenta Informaticae, vol. 69, no. 4, pp. 411-425, 2006

Authors: Xia, Lirong | Li, Sanjiang

Article Type: Research Article

Abstract: Region Connection Calculus (RCC) is one primary formalism of qualitative spatial reasoning. Standard RCC models are continuous ones where each region is infinitely divisible. This contrasts sharply with the predominant use of finite, discrete models in applications. In a recent paper, Li et al. (2004) initiate a study of countable models that can be constructed step by step from finite models. Of course, some basic problems are left unsolved, for example, how many non-isomorphic countable RCC …models are there? This paper investigates these problems and obtains the following results: (i) the exotic RCC model described by Gotts (1996) is isomorphic to the minimal model given by Li and Ying (2004); (ii) there are continuum many non-isomorphic minimal RCC models, where a model is minimal if it can be isomorphically embedded in each RCC model. Show more

Keywords: Qualitative Spatial Reasoning, Region Connection Calculus, minimal RCC models

Citation: Fundamenta Informaticae, vol. 69, no. 4, pp. 427-446, 2006