Dependency quantified Boolean formulas (DQBF ) extend quantified Boolean formulas with Henkin-style partially ordered quantifiers. It has been shown that this is likely to yield more succinct representations at the price of a computational blow-up from PSPACE to NEXPTIME. In this paper, we consider dependency quantified Horn formulas (DQHORN ), a subclass of DQBF, and show that the computationa...

We use results on modal definability of first-order formulas to reduce the problem of answering conjunctive queries over knowledge bases (of any expressivity) to checking inconsistency of those knowledge bases extended with a number of ALCI concept assertions. This reduction has been shown to work for conjunctive queries without cycles that only involve bound variables. In this paper, we presen...

A syntax and semantics of types, terms and formulas for coalgebras of polynomial functors is developed, extending earlier work [4] on monomial coalgebras to include functors constructed using coproducts. A modified ultrapower construction for polynomial coalgebras is introduced, adapting the conventional ultrapower to retain only those states that evaluate observable terms in a standard way. A ...

Theodes of semantic interpretation which wish to capture as many generalizations as possible must face up to the manifoldly ambiguous and contextually dependent nature of word meaning? In this paper I present a two-level scheme of semantic interpretation in which the first level deals with the semantic consequences of'syntactic structure and the second with the choice of word meaning. On the fi...

We present several calculi that integrate equality handling by superposition and ordered paramodulation into a free variable tableau calculus. We prove completeness of this calculus by an adaptation of themodel generation [1, 13] technique commonly used for completeness proofs of resolution calculi. The calculi and the completeness proof are compared to earlier results of Degtyarev and Voronkov...

A formula (x) in the one non-logical symbol " with one free variable x is Russell if the sentence :9r8x(x"r $ (x)) is logically valid. This note describes a pattern common to the classical examples of Russell formulas, adds a couple of new ones, and constructs many formulas that are near-Russell.

Language 2 Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 λ-calculus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Constants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ....

We study the semantics of SPARQL queries with optional matching features under entailment regimes. We argue that the normative semantics may lead to answers that are in conflict with the intuitive meaning of optional matching, where unbound variables naturally represent unknown information. We propose an extension of the SPARQL algebra that addresses these issues and is compatible with any enta...

Inference rule substitution of equals for equals has been formalized in terms of simple substitution which performs a replacement even though a free occurrence of a variable is captured contextual substitution which prevents such capture and func tion application We show that in connection with pure rst order predicate calculus the function application and no capture versions of the inference r...

In a recently published paper J. C. C. McKinsey has pointed out some difficulties which arise from Axiom I of my theory of probability implication. This axiom states the unambiguity of the degree p of a given probability implication (03VP) for the case that the class 0 is not empty, a condition formulated by (o), but postulates ambiguity of p in case of an empty class 0, this condition being fo...