Varieties like groups, rings, or Boolean algebras have the property that, in any of their members, the lattice of congruences is isomorphic to a lattice of more manageable objects: e.g. normal subgroups of groups, two-sided ideals of rings, …lters (or ideals) of Boolean algebras. Abstract algebraic logic can explain these phenomena at a rather satisfactory level of generality: in every member A...

This paper describes Hyper-G, a new hypermedia information system which combines the best of Gopher, WAIS, and World Wide Web. Hyper-G is speci cally designed as a distributed, large-scale hypermedia information system supporting navigation in a large body of dynamically changing information without becoming \lost in hyperspace". Users may choose a hierarchical navigation paradigm, click on hyp...

This paper discusses and compares various answers to the question when argumentation is deductive. includes an answer questions defeasible whether a subclass of deductive or it distinct form argumentation. It concluded that as conceived by Philosophers like Pollock Rescher formalised in ASPIC+ framework systems Defeasible Logic Programming, are semantically different categories. For this reason...

The basic assumption in relational and deductive databases is that there are no gaps in our knowledge. That is, the database cannot store data that contain null values or data that is indeenite. In practical situations knowledge is not precise, and there are gaps in our knowledge. These gaps may be due to null values in the data, may arise when we combine several databases that lead to inconsis...

The focus of this paper lies on the proof-theory for extensions of Logic Programming in which it is possible to draw negative conclusions both in a direct (i.e., based on a proof) and in an indirect (i.e., based on the lack of a proof) way. These extensions are provided with a rule-based deductive system in the sense of the work of Jager [8] for Normal Logic Programs. Rule-based deductive syst...

The aim of this paper is to propose dynamic logic as a cotmnon logical framework to describe and identify the most relevant formal characteristics of multi-language logical architectures (MLA) in order to investigate the expressive power of the knowledge bases that can be built upon them. In general, a MLA allows to build knowledge bases as a set of units with initial local theories written in ...

Abstract State Machines (ASMs, for short) provide a practical new computational model which has been applied in the area of software engineering for systems design and analysis. However, reasoning about ASM models occurs, not within a formal deductive system, but basically in the classical informal proofs style of mathematics. Several formal verification approaches for proving correctness of AS...

We propose a method for controlling chaos and hyper-chaos by applying continuous proportional feedback to the system variables and their derivatives. The method has been applied successfully in six-order coupled Chua’s hyper-chaotic circuit system. The theoretical analysis and numerical simulation results show that unstable fixed points embedded in hyper-chaotic attractors can be stabilized and...

Three common approaches for deriving or predicting instantiated relations are information extraction, deductive reasoning and machine learning. Information extraction uses subsymbolic unstructured sensory information, e.g. in form of texts or images, and extracts statements using various methods ranging from simple classifiers to the most sophisticated NLP approaches. Deductive reasoning is bas...