BiLog - A Framework for Structural Logics (talk)

Talk given at Forum on Separation Logics, Cambridge 14.03.0

Communication Interference in Mobile Boxed Ambients (talk)

Talk given at FST&TCS 200

A Note on Logic Programming Fixed-Point Semantics

In this paper, we present an account of classical Logic Programming fixed-point semantics in terms of two standard categorical constructions in which the least Herbrand model is characterized by properties of universality. In particular, we show that, given a program $P$, the category of models of $P$ is reflective in the category of interpretations for $P$. In addition, we show that the immediate consequence operator gives rise to an endofunctor ${T}_P$ on the category of Herbrand interpretations for $P$ such that category of algebras for ${T}_P$ is the category of Herbrand models of $P$. As consequences, we have that the least Herbrand model of $P$ is the least fixed-point of ${T}_P$ and is the reflection of the empty Herbrand interpretation

Global Computing II. Terms of reference for the FP6-EU-FET call.

The European Commission has decided to continue and develop its FET “Global Computing,” and will shortly announce the opening of “Global Computing II.” The call is expected in May 2004, with application deadlines in September, and expected start date for selected projects in March 2005

Engineering Trust-based Software Intensive Systems

Abstract of a keynote speech given at the Strategic Research Workshop on Engineering Software Intensive Systems

A Calculus for Trust Management (talk)

Talk given at GC 2004: MyThS/MIKADO/DART Meeting, Venice 16.06.0

Preface

Overview of the contents of "Foundations of Software Science and Computational Structures: Selected papers from FOSSACS 2005

An Approach to the Category of Net Computations

We introduce the notion of strongly concatenable process as a refinement of concatenable processes [DMM89] which can be expressed axiomatically via a functor $Q[-]$ from the category of Petri nets to an appropriate category of symmetric strict monoidal categories, in the precise sense that, for each net $N$, the strongly concatenable processes of $N$ are isomorphic to the arrows of $Q[N]$. In addition, we identify a coreflection right adjoint to $Q[-]$ and characterize its replete image, thus yielding an axiomatization of the category of net computations

On the Category of Petri Net Computations

We introduce the notion of strongly concatenable process as a refinement of concatenable processes [DMM89] which can be expressed axiomatically via a functor $Q[-]$ from the category of Petri nets to an appropriate category of symmetric strict monoidal categories, in the precise sense that, for each net $N$, the strongly concatenable processes of $N$ are isomorphic to the arrows of $Q[-]$. In addition, we identify a coreflection right adjoint to $Q[-]$ and characterize its replete image, thus yielding an axiomatization of the category of net computations

Axiomatizing Petri Net Concatenable Processes

The concatenable processes of a Petri net $N$ can be characterized abstractly as the arrows of a symmetric monoidal category $P[N]$. Yet, this is only a partial axiomatization, since $P[N]$ is built on a concrete, ad hoc chosen, category of symmetries. In this paper we give a fully equational description of the category of concatenable processes of $N$, thus yielding an axiomatic theory of the noninterleaving behaviour of Petri nets