On logical wholeness of an (axiomatic) formal theory
On Markov Properties Of Finitely Presented Groups
On Markov properties of finitely presented groups.
On modelling of large variable systems of higher degree by means of language systems
On models of certain formulas with a predicate letter of lenght n
On MPT-implication functions for fuzzy logic.
This paper deals with numerical functions J : [0,1] x [0,1] → [0,1] able to functionally express operators →: [0,1]X x [0,1]Y → [0,1]XxY defined as (μ → σ)(x,y) = J(μ(x),σ(y)), and verifying either Modus Ponens or Modus Tollens, or both. The concrete goal of the paper is to search for continuous t-norms T and strong-negation functions N for which it is either T(a, J(a,b)) ≤ b (Modus Ponens) or T(N(b), J(a,b)) ≤ N(a) (Modus Tollens), or both, for all a,b in [0,1] and a given J. Functions J are taken...
On Multiset Ordering
Formalization of a part of [11]. Unfortunately, not all is possible to be formalized. Namely, in the paper there is a mistake in the proof of Lemma 3. It states that there exists x ∈ M1 such that M1(x) > N1(x) and (∀y ∈ N1)x ⊀ y. It should be M1(x) ⩾ N1(x). Nevertheless we do not know whether x ∈ N1 or not and cannot prove the contradiction. In the article we referred to [8], [9] and [10].
On necessary but not-sufficient conditions.
On one definition of grammatical categories
On permutographs
On practical problems with the explanation of the difference between possibility and probability
On probability of first order formulas in a given model
On pseudo BE-algebras
In this paper, we introduce the notion of pseudo BE-algebra which is a generalization of BE-algebra. We define the concepts of pseudo subalgebras and pseudo filters and prove that, under some conditions, pseudo subalgebra can be a pseudo filter. We prove that every homomorphic image and pre-image of a pseudo filter is also a pseudo filter. Furthermore, the notion of pseudo upper sets in pseudo BE-algebras introduced and is proved that every pseudo filter is an union of pseudo upper sets.
On ()-fuzzy filters of pseudo-BL algebras.
On reduced products of Kripke models.
On regular congruences
On representations of logics
On Rough Subgroup of a Group
This article describes a rough subgroup with respect to a normal subgroup of a group, and some properties of the lower and the upper approximations in a group.
On Semantics of a Term Calculus for Classical Logic
On sequent calculi for intuitionistic propositional logic
The well-known Dyckoff's 1992 calculus/procedure for intuitionistic propositional logic is considered and analyzed. It is shown that the calculus is Kripke complete and the procedure in fact works in polynomial space. Then a multi-conclusion intuitionistic calculus is introduced, obtained by adding one new rule to known calculi. A simple proof of Kripke completeness and polynomial-space decidability of this calculus is given. An upper bound on the depth of a Kripke counter-model is obtained.