In program algebra, an algebraic theory of single-pass instruction sequences, three congruences on instruction sequences are paid attention to: instruction sequence congruence, structural congruence, and behavioural congruence. Sound and complete axiom systems for the first two congruences were already given in early papers on program algebra. The current paper is the first one that is concerne...

The aim of this paper is to further develop the congruence theory on lattice implication algebras. Firstly, we introduce the notions of vague similarity relations based on vague relations and vague congruence relations. Secondly, the equivalent characterizations of vague congruence relations are investigated. Thirdly, the relation between the set of vague filters and the set of vague congruence...

Prefix iteration is a variation on the original binary version of the Kleene star operation P Q, obtained by restricting the first argument to be an atomic action. The interaction of prefix iteration with silent steps is studied in the setting of Milner’s basic CCS. Complete equational axiomatizations are given for four notions of behavioural congruence over basic CCS with prefix iteration, viz...

Article history: Received 1 March 2011 Available online 9 March 2011 The relation of interest–major congruence to indicators of college success was examined as it was moderated by environmental constraint, individual flexibility, and congruence definition in an initial sample of 88,813 undergraduates (38,787 men and 50,026 women) from 42 different colleges and universities in 16 states. College...

Let A = (A;F ) be an algebra and ConA its congruence lattice. Recall that A is congruence uniform (see e.g. [1], [5]) if for each Θ ∈ ConA and every a, b ∈ A, card[a]Θ = card[b]Θ. Examples of congruence uniform algebras are e.g. groups, rings or Boolean algebras. A variety V is congruence uniform if each A ∈ V has this property. It was proved by W. Taylor [5] that every congruence uniform varie...

Congruence among the Intended, Implemented and Attained “Thinking and Life Style” Curricula in the Eighth Grade M. A. Jamalifar Sh. Hashemi Moghadam, Ph.D. Z. Abedi Karajiban, Ph.D. A.R. Faghihi, Ph.D. The present study was carried out to examine the congruence among the intended, implemented and attained “thinking and life style” curricula in th...