ISSN:0942-5616    

DOI:10.1002/malq.19920380102

出版商:WILEY‐VCH Verlag Berlin GmbH    

年代:1992

数据来源: WILEY

ISSN:0942-5616    

DOI:10.1002/malq.19920380103

出版商:WILEY‐VCH Verlag Berlin GmbH    

年代:1992

数据来源: WILEY

摘要:

AbstractWe prove that any binary relation with underlying set (base)Ewith cardinalityn>6 is reconstructible from its restrictions of cardinality 2, 3, 4 and (n‐ 1). In part I we characterize relationsRandR' on the same baseEsuch thatR/XandR'/Xare isomorphic for every subsetXofEwith cardinality 2, 3, 4. In part II we shall prove thatRandR' are isomorphic as soon asn>6 whenR/XandR/X' are isomorphic for every subsetXofEwith cardinality 2, 3, 4 and (n‐

ISSN:0942-5616    

DOI:10.1002/malq.19920380104

出版商:WILEY‐VCH Verlag Berlin GmbH    

年代:1992

数据来源: WILEY

摘要:

AbstractIn this paper we propose a new set of rules for a judgement calculus, i.e. a typed lambda calculus, based on Intuitionistic Linear Logic; these rules ease the problem of defining a suitable mathematical semantics. A proof of the canonical form theorem for this new system is given: it assures, beside the consistency of the calculus, the termination of the evaluation process of every well‐typed element. The definition of the mathematical semantics and a completeness theorem, that turns out to be a representation theorem, follow. This semantics is the basis to obtain a semantics for the evaluation process of every well‐typed program. 1991 MSC: 03B20, 03

ISSN:0942-5616    

DOI:10.1002/malq.19920380105

出版商:WILEY‐VCH Verlag Berlin GmbH    

年代:1992

数据来源: WILEY

摘要:

AbstractWe consider iterations of satisfaction classes and apply them to construct expansions of models of Peano arithmetic to models of A −2|Δ 11+∑ 11‐AC. 1991 MSC:

ISSN:0942-5616    

DOI:10.1002/malq.19920380106

出版商:WILEY‐VCH Verlag Berlin GmbH    

年代:1992

数据来源: WILEY

摘要:

AbstractThe aim of this paper is to extend the semantic analysis of tense logic in Rescher/Urquhart [3] to propositional dynamic logic without*. For this we develop a nested sequential calculus whose axioms and rules directly reflect the steps in the semantic analysis. It is shown that this calculus, with the cut rule omitted, is complete with respect to the standard semantics. It follows that cut elimination does hold for this nested sequential calculus. MSC: 03B45.

ISSN:0942-5616    

DOI:10.1002/malq.19920380107

出版商:WILEY‐VCH Verlag Berlin GmbH    

年代:1992

数据来源: WILEY

摘要:

AbstractIn this note we treat maximal and minimal normal subgroups of a superstable group and prove that these groups are definable under certain conditions. Main tool is a superstable version of Zil'ber's indecomposability theorem. MSC: 03C60.

ISSN:0942-5616    

DOI:10.1002/malq.19920380108

出版商:WILEY‐VCH Verlag Berlin GmbH    

年代:1992

数据来源: WILEY

摘要:

AbstractWe investigate a theory of Frege structures extended by the Myhill‐Flagg hierarchy of implications. We study its relation to a property theory with an approximation operator and we give a proof theoretical analysis of the basic system involved. MSC: 03F35, 03D6

ISSN:0942-5616    

DOI:10.1002/malq.19920380109

出版商:WILEY‐VCH Verlag Berlin GmbH    

年代:1992

数据来源: WILEY

摘要:

AbstractThe still unsettled decision problem for the restricted purely universal formulae ((∀)0‐formulae) of the first order set‐theoretic language based over =, ∈ is discussed in relation with the adoption or rejection of the axiom of foundation. Assuming the axiom of foundation, the related finite set‐satisfiability problem for the very significant subclass of the (∀)0‐formulae consisting of the formulae involving only nested variables of level 1 is proved to be semidecidable on the ground of a reflection property over the hereditarily finite sets, and various extensions of this result are obtained. When variables are restricted to range only over sets, in universes with infinitely many urelements the set‐satisfiability problem is shown to be solvable provided the axiom of foundation is assumed; if it is not, then the decidability of a related derivability problem still holds. That, in turn, suggests the alternative adoption of an antifoundation axiom under which the set‐satisfiability problem is also solvable (of course with different answers). Turning to set theory without urelements, assuming a form of Boffa's antifoundation axiom, the complement of the set‐satisfiability problem for the full class of Δ0‐formulae is shown to be semidecidable; a result that is known not to hold, for the set‐satisfiability problem itself, even for a very restricted sub

ISSN:0942-5616    

DOI:10.1002/malq.19920380110

出版商:WILEY‐VCH Verlag Berlin GmbH    

年代:1992

数据来源: WILEY

摘要:

AbstractWe shall prove here that any binary relation on a baseEwith cardinalityn>6 is reconstructible from its restrictions of cardinality 2, 3, 4 and (n‐ 1). This proof needs results of part I of this paper where we characterize any pair of relationsR,R' which are 2‐, 3‐ and 4‐hypomorphic. As a corollary we obtain that any binary relation is (n‐ 4)‐reconstructibl

ISSN:0942-5616    

DOI:10.1002/malq.19920380111

出版商:WILEY‐VCH Verlag Berlin GmbH    

年代:1992

数据来源: WILEY