We prove some results about the limitations of the expressive power of quantiiers on nite structures. We deene the concept of a bounded quantiier and prove that every relativizing quantiier which is bounded is already rst-order deenable (Theorem 3.8). We weaken the concept of congruence closed (see 6]) to weakly congruence closed by restricting to congruence relations where all classes have the...

This paper ooers a complete inference system for branching bisimulation congruence on a basic sublanguage of CCS for representing regular processes with silent moves. Moreover, complete axiomatizations are provided for the guarded expressions in this language, representing the divergence-free processes, and for the recursion-free expressions, representing the nite processes. Furthermore it is a...

According to a central claim of Kornblum's dimensional-overlap model, response-related processes do not start before stimulus-related processes have been completed, which implies an additive relationship between effects of stimulus-stimulus congruence and stimulus-response compatibility. Three experiments were conducted to test this prediction. In Exp. 1, additive effects of color-word congruen...

A number of studies on political representation focus on the comparative assessments of citizen ideological congruence. But this literature has largely overlooked an important topic: the representation of social groups. While present studies of congruence investigate whether some countries perform better than others in terms of the levels of median citizen congruence, they cannot say much about...

This study aimed to examine the importance of value congruence in work engagement and to extend the previous literature by investigating the potential mediating effects of autonomous and controlled motivation in this relationship. The Perceived Value Congruence, Autonomous and Controlled Motivation and Work Engagement scales were administered to 767 teachers in Mainland China. Correlation analy...

T. Dent, K. Kearnes and Á. Szendrei have defined the derivative, Σ′, of a set of equations Σ and shown, for idempotent Σ, that Σ implies congruence modularity if Σ′ is inconsistent (Σ′ |= x ≈ y). In this paper we investigate other types of derivatives that give similar results for congruence n-permutability for some n, and for congruence semidistributivity.

Congruence lattices of algebras in various varieties have been studied extensively in the literature. For example, congruence lattices (i.e. lattices of ideals) of Boolean algebras were characterized by Nachbin [18] (see also Gratzer [9] and Jonsson [16]) while congruence lattices of semilattices were investigated by Papert [19], Dean and Oehmke [4] and others. In this paper we initiate the inv...

We show that any congruence lower semimodular variety whose 2-generatecl free algebra is finite must be congruence modular.

We characterize ideals of ortholattices which are congruence kernels. We show that every congruence class determines a kernel.

In this paper we introduce the notion of a congruence rich variety of algebras, and investigate which locally finite subvarieties of such a variety are relatively finitely based. We apply the results obtained to investigate the finite axiomatizability of an interesting variety generated by a particular five-element directoid. Roughly speaking, congruence rich varieties are those in which all la...