Search results for "languages"
showing 10 items of 2101 documents
GEOMETRIC EQUIVALENCE OF ALGEBRAS
2001
In this paper, we study the geometric equivalence of algebras in several varieties of algebras. We solve some of the problems formulated in [2], in particular, that of geometric equivalence for real-closed fields and finitely generated commutative groups.
Unification in superintuitionistic predicate logics and its applications
2018
AbstractWe introduce unification in first-order logic. In propositional logic, unification was introduced by S. Ghilardi, see Ghilardi (1997, 1999, 2000). He successfully applied it in solving systematically the problem of admissibility of inference rules in intuitionistic and transitive modal propositional logics. Here we focus on superintuitionistic predicate logics and apply unification to some old and new problems: definability of disjunction and existential quantifier, disjunction and existential quantifier under implication, admissible rules, a basis for the passive rules, (almost) structural completeness, etc. For this aim we apply modified specific notions, introduced in proposition…
Some Problems on Homomorphisms and Real Function Algebras
2001
In this paper we solve a problem about the representation of all homomorphisms on a real function algebra as point evaluations and another two about function algebras in which homomorphisms are point evaluations on sequences in the algebra.
Algebraic Results on Quantum Automata
2004
We use tools from the algebraic theory of automata to investigate the class of languages recognized by two models of Quantum Finite Automata (QFA): Brodsky and Pippenger’s end-decisive model, and a new QFA model whose definition is motivated by implementations of quantum computers using nucleo-magnetic resonance (NMR). In particular, we are interested in the new model since nucleo-magnetic resonance was used to construct the most powerful physical quantum machine to date. We give a complete characterization of the languages recognized by the new model and by Boolean combinations of the Brodsky-Pippenger model. Our results show a striking similarity in the class of languages recognized by th…
Sequential formula translation
1983
The syntax of an algorithmic language such as ALGOL is conveniently described as a sequence of states indicated by an element called cellar. Transitions are controlled by admissible state- s ymbol pairs which may be represented by a transition matrix. This description of syntax furnishes at the same time an extremely simple rule for translating into machine programs statements in the algorithmic language. Sequential treatment, however, is not feasible in the case of certain optimizing processes such as recursive address calculation.
On Combinatorial Generation of Prefix Normal Words
2014
A prefix normal word is a binary word with the property that no substring has more 1s than the prefix of the same length. This class of words is important in the context of binary jumbled pattern matching. In this paper we present an efficient algorithm for exhaustively listing the prefix normal words with a fixed length. The algorithm is based on the fact that the language of prefix normal words is a bubble language, a class of binary languages with the property that, for any word w in the language, exchanging the first occurrence of 01 by 10 in w results in another word in the language. We prove that each prefix normal word is produced in O(n) amortized time, and conjecture, based on expe…
Linguistic Analysis and Ancient Indo-European Languages
2015
Using modern linguistic theory to describe ‘dead’ languages is one of the theoretical and methodological challenges in contemporary linguistic research. In fact, theories of the twentieth century mostly aimed to account for speakers’ linguistic competence, thus basing their analysis on live speakers and their intuitions. However, drawing on evidence from languages such as Vedic, Greek, Latin, Hittite, Gothic, Celtic and Proto-Indo-European itself, the relevance of the ancient Indo-European languages to contemporary linguistic theory has been constantly shown, since the rise of the linguistic sciences in the early nineteenth century. In fact, the observation of ancient Indo-European language…
Aktuālas valodu un literatūras mācību problēmas
1994
Rakstu krājumā iztirzātas vairākas pedagoģiskām augstskolām un vispārizglītojošām skolām aktuālas valodu un latviešu literatūras mācību problēmas.
On a new proof of Moser's twist mapping theorem
1976
Based on a new idea of the author, a new proof of J. Moser's twist mapping theorem is presented.