Unfolding-based Improvements on Fuzzy Logic Programs

AbstractUnfolding is a semantics-preserving program transformation technique that consists in the expansion of subexpressions of a program using their own definitions. In this paper we define two unfolding-based transformation rules that extend the classical definition of the unfolding rule (for pure logic programs) to a fuzzy logic setting. We use a fuzzy variant of Prolog where each program clause can be interpreted under a different (fuzzy) logic. We adapt the concept of a computation rule, a mapping that selects the subexpression of a goal involved in a computation step, and we prove the independence of the computation rule. We also define a basic transformation system and we demonstrate its strong correctness, that is, original and transformed programs compute the same fuzzy computed answers. Finally, we prove that our transformation rules always produce an improvement in the efficiency of the residual program, by reducing the length of successful Fuzzy SLD-derivations

Automatic Proving of Fuzzy Formulae with Fuzzy Logic Programming and SMT

In this paper we deal with propositional fuzzy formulae containing severalpropositional symbols linked with connectives defined in a lattice of truth degrees more complex than Bool. We firstly recall an SMT (Satisfiability Modulo Theories) based method for automatically proving theorems in relevant infinitely valued (including Łukasiewicz and G¨odel) logics. Next, instead of focusing on satisfiability (i.e., proving the existence of at least one model) or unsatisfiability, our interest moves to the problem of finding the whole set of models (with a finite domain) for a given fuzzy formula. We propose an alternative method based on fuzzy logic programming where the formula is conceived as a goal whose derivation tree contains on its leaves all the models of the original formula, by exhaustively interpreting each propositional symbol in all the possible forms according the whole setof values collected on the underlying lattice of truth-degrees

Mathematics in Software Reliability and Quality Assurance

This monograph concerns the mathematical aspects of software reliability and quality assurance and consists of 11 technical papers in this emerging area. Included are the latest research results related to formal methods and design, automatic software testing, software verification and validation, coalgebra theory, automata theory, hybrid system and software reliability modeling and assessment

Proceedings of the 2008 Oxford University Computing Laboratory student conference.

This conference serves two purposes. First, the event is a useful pedagogical exercise for all participants, from the conference committee and referees, to the presenters and the audience. For some presenters, the conference may be the first time their work has been subjected to peer-review. For others, the conference is a testing ground for announcing work, which will be later presented at international conferences, workshops, and symposia. This leads to the conference's second purpose: an opportunity to expose the latest-and-greatest research findings within the laboratory. The fourteen abstracts within these proceedings were selected by the programme and conference committee after a round of peer-reviewing, by both students and staff within this department

Learning from innovation echoes in mature organizations - The case of the automotive industry

International audienceIn competitive industries, intensive and repeated innovation is a recognized necessity (Wheelwright and Clark, 1992; Le Masson et al., 2010). Literature on innovation (Utterback, 1994; Henderson & Clark, 1990) distinguishes Dominant Design revisions (radical innovations) from local improvements (incremental innovations). Regarding the innovation process management, one success factor lies in the knowledge articulation between front end and new product development (NPD) stages (Koen et al, 2002; Cooper et al, 2001). Then, central issue becomes NPD stakeholders' management (Elias et al., 2002) and their ability to establish perennial learning dynamics across the two parts of the organization (O'Connor, 2008). Our paper fits into this research field for local innovations on the dominant design. We discuss the role of technical expertise level of NDP stakeholders involved in early stages. The research mobilized two longitudinal studies (Yin, 1989) carried out with a global car manufacturer since 2005, one focusing on the innovation management process and organization, while the other was devoted to learning dynamics of engineering development departments. Leading as collaborative management research (Hatchuel and David, 2007), analyses were enhanced through deep interviews with project managers, technical experts and decision-makers. Analyzing local innovation impacts, we find that effect of breakthrough innovation projects on NPD organization was similar to waves: close expertise are quickly and strongly affected while distant expertise are more weakly and later affected. Our research material shows that tracking of key stakeholders is based on functional division of the organization whereas force and temporality of the innovation impact could potentially follow other propagation logic. Stakeholders identified by the organization as key actors could be in reality weakly impacted but we observed they were able to convey useful knowledge to heavily affected actors inside their organization when they had a high level of technical expertise of the dominant design. Expertise robustness plays a screen role that returns, as an amplified echo, the innovation low impact on their technical perimeter toward those heavily impacted