Simulations and bisimulations are known to be useful for abstracting and comparing formal systems, and they have recently been introduced into fuzzy systems. In this study, we provide sound and complete logical characterizations for simulation and bisimulation, which are defined over fuzzy labeled transition systems via two variants of the Hennessy-Milner Logic. The logic for characterizing fuz...

The paper proposes a way to add marketing into the standard threshold model of social networks. Within this framework, the paper studies logical properties of the influence relation between sets of agents in social networks. Two different forms of this relation are considered: one for promotional marketing and the other for preventive marketing. In each case a sound and complete logical system ...

We introduce a new notion of structural refinement, a sound abstraction of logical implication, for the modal nucalculus. Using new translations between the modal nu-calculus and disjunctive modal transition systems, we show that these two specification formalisms are structurally equivalent. To the best of our knowledge, this is the first time such a close relationship between a logical and a ...

Proof systems play a major role in the formal study of diagrammatic logical systems. Typically, the style of inference is not directly comparable to traditional sentential systems, to study the the diagrammatic aspects of inference. In this work, we present a proof system for Euler diagrams with shading in the style of sequent calculus. We prove it to be sound and complete. Furthermore we outli...

We propose a technique for dealing with the high complexity of reasoning under propositional default logic and circumscription. The technique is based on the notion of approximation: A logical consequence relation is computed by means of sound and progressively \more complete" relations, as well as complete and progressively \more sound" ones. Both sequences generated in this way converge to th...

We present a Prolog program that implements a sound and complete theorem prover for first-order intuitionistic logic. It is based on free-variable semantic tableaux extended by an additional string unification to ensure the particular restrictions in intuitionistic logic. Due to the modular treatment of the different logical connectives the implementation can easily be adapted to deal with othe...

Logical frameworks have enjoyed wide adoption as meta-languages for describing deductive systems. While the techniques for representing object languages in logical frameworks are relatively well understood, languages and techniques for metaprogramming with them are much less so. This paper presents work in progress on a programming language called Rogue-Sigma-Pi (RSP), in which general programs...