It is widely believed that in principle it’s possible to reduce most of present-day mathematics to reasoning in a formal logical system. The technical difficulty of actually doing so is quite formidable. However, the arrival of the computer is changing this situation, since computers are good at helping with such tedious symbolic manipulation. The computer formalization of mathematics is now a ...

We suggest that mechanized multi-agent deontic logics might be appropriate vehicles for engineering trustworthy robots. Mechanically checked proofs in such logics can serve to establish the permissibility (or obligatoriness) of agent actions, and such proofs, when translated into English, can also explain the rationale behind those actions. We use the logical framework Athena to encode a natura...

A novel protocol has been formally analyzed using the prover Isabelle/HOL, following the inductive approach described in earlier work [10]. There is no limit on the length of a run, the nesting of messages or the number of agents involved. A single run of the protocol delivers session keys for all the agents, allowing neighbours to perform mutual authentication. The basic security theorem state...

As airspace becomes ever more crowded, air traffic management must reduce both space and time between aircraft to increase throughput, and on-board collision avoidance systems become ever more important. These systems and the policies that they implement must be extremely reliable. In this paper we consider implementations of distributed collision avoidance policies designed to work in environm...

We present an expressive information-flow control type system with recursive types, existential label polymorphism, and impredicative polymorphism for a higher-order programming language state. give novel semantic model of this show that well-typed programs satisfy termination-insensitive noninterference. Our approach supports compositional integration syntactically ill-typed---but semantically...

UML Sequence Diagrams are widely used in software development. When putting to applications such as code generation, model simulation and other automated analysis, the formalization of UML Sequence Diagrams, especially correctness of it becomes increasingly important. This article presents the formal specification including denotational semantics and operational semantics of UML Sequence Diagra...