133 research outputs found
A Framework to Formalise the MDE Foundations
International audienceDomain-Specific Language (DSL) are getting more and more popular and are being used in critical systems like aerospace and car industries. Methods for simulating and validating DSL models are now necessary in order to make the new software generation more reliable and less costly. Developing analysis tools for DSL requires the definition of models semantics. In this paper, we propose a framework to give a formal foundation of the Model-Driven Engineering (MDE) approach. We separate the usually common notions of models and modelling languages associating to each of them a different goal. In order to prove the consistency of our proposal we express a subset of EMOF, its static semantics and validate its meta-circularity
Extensions of Simple Conceptual Graphs: the Complexity of Rules and Constraints
Simple conceptual graphs are considered as the kernel of most knowledge
representation formalisms built upon Sowa's model. Reasoning in this model can
be expressed by a graph homomorphism called projection, whose semantics is
usually given in terms of positive, conjunctive, existential FOL. We present
here a family of extensions of this model, based on rules and constraints,
keeping graph homomorphism as the basic operation. We focus on the formal
definitions of the different models obtained, including their operational
semantics and relationships with FOL, and we analyze the decidability and
complexity of the associated problems (consistency and deduction). As soon as
rules are involved in reasonings, these problems are not decidable, but we
exhibit a condition under which they fall in the polynomial hierarchy. These
results extend and complete the ones already published by the authors. Moreover
we systematically study the complexity of some particular cases obtained by
restricting the form of constraints and/or rules
The reversibility of cellular automata on trees with loops
[EN] In this work the notion of linear cellular automata on trees with loops is introduced and the reversibility problem in some particular cases is tackled. The explicit expressions of the inverse cellular automata are computed
Quantum Branching Programs and Space-Bounded Nonuniform Quantum Complexity
In this paper, the space complexity of nonuniform quantum computations is
investigated. The model chosen for this are quantum branching programs, which
provide a graphic description of sequential quantum algorithms. In the first
part of the paper, simulations between quantum branching programs and
nonuniform quantum Turing machines are presented which allow to transfer lower
and upper bound results between the two models. In the second part of the
paper, different variants of quantum OBDDs are compared with their
deterministic and randomized counterparts. In the third part, quantum branching
programs are considered where the performed unitary operation may depend on the
result of a previous measurement. For this model a simulation of randomized
OBDDs and exponential lower bounds are presented.Comment: 45 pages, 3 Postscript figures. Proofs rearranged, typos correcte
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