In this paper we present several fuzzy logics trying to capture different notions of necessity (in the sense of Possibility theory) for Gödel logic formulas. Based on different characterizations of necessity measures on fuzzy sets, a group of logics with Kripke style semantics are built over a restricted language, namely a two level language composed of non-modal and modal formulas, the latter ...

In this paper, we propose a proof system for reasoning on certain specifications of secure authentication systems. For this purpose, a new logic, sequence-indexed linear-time temporal logic (SLTL), is obtained semantically from standard linear-time temporal logic (LTL) by adding a sequence modal operator that represents a sequence of symbols. By this sequence modal operator, we can appropriatel...

Modal Kleene algebras are Kleene algebras enriched by forward and backward box and diamond operators. We formalise the symmetries of these operators as Galois connections, complemetarities and dualities. We study their properties in the associated operator algebras and show that the axioms of relation algebra are theorems at the operator level. Modal Kleene algebras provide a unifying semantics...

On the assumption that ISs involve a silent generic quantifier GEN, which is taken to be a modal operator, it has been argued (Krifka et al. 1995) that GEN can have different interpretations, corresponding to those of overt modalities in ISs sentences. In this view, (2-a) would be interpreted as in (2b), and the silent operator GEN in (2-a) would have the deontic flavor of the overt modal must ...

In this paper, we extend circumscription [McCarthy, 80] to a propositional modal logic of knowledge of one agent. Instead of circumscribing a predicate, we circumscribe the knowledge operator "K" in a formula. In order to have a nontrivial circumscription schema, we extend $5 modal logic of knowledge by adding another modality "Val" and a universal quantifier over base sentences (sentences whic...

The objective of this research was to assess the effectiveness of using a multi-modal interface for adaptive automation (AA) of human control of a simulated telerobotic (remote-control, semi-autonomous robotic) system. We investigated the use of one or more sensory channels to cue dynamic control allocations to a human operator or computer, as part of AA, and to support operator system/situatio...

The propositional ì-calculus is an extension of the modal system K with a least fixpoint operator. Kozen posed a question about completeness of the axiomatisation of the logic which is a small extension of the axiomatisation of the modal system K. It is shown that this axiomatisation is complete. §

We consider propositional modal logic with two modal operators and [ 6 =]. In topological semantics is interpreted as an interior operator and [ 6=] as difference. We show that some important topological properties are expressible in this language. In addition, we present a few logics and proofs of f.m.p. and of completeness theorems.

We introduce a propositional modal logic PP of “pure” provability in arbitrary theories (propositional or first-order) where the 2 operator means “provable in all extensions”. This modal logic has been considered in another guise by Kripke. An axiomatization and a decision procedure are given and the 23 subtheory is characterized.

In this paper we present a modal extension of logic programming which provides reasoning capabilities in a multiagent situation The language con tains embedded implications modal operators ai to represent agent beliefs together with a kind of common knowledge operator In this language we can also de ne modules compose them in several ways and also we can perform hypothetical reasoning