The width of a subset C of the vertices of a distance-regular graph is the maximum distance which occurs between elements of C. Dually, the dual width of a subset in a cometric association scheme is the index of the “last” eigenspace in the Q-polynomial ordering to which the characteristic vector of C is not orthogonal. Elementary bounds are derived on these two new parameters. We show that any...

We continue our study of matrix models of dually weighted graphs. Among the attractive features of these models is the possibility to interpolate between ensembles of regular and random two-dimensional lattices, relevant for the study of the crossover from twodimensional flat space to two-dimensional quantum gravity. We further develop the formalism of large N character expansions. In particula...

A graph is dually chordal if it is the clique graph of a chordal graph. Alternatively, a graph is dually chordal if it admits a maximum neighbourhood order. This class generalizes known subclasses of chordal graphs such as doubly chordal graphs, strongly chordal graphs and interval graphs. We prove that Vizing's total-colour conjecture holds for dually chordal graphs. We describe a new heuristi...

This highlight describes the characteristics and inpatient utilization of under age 65 disabled California Medicare beneficiaries by dual eligible status (i.e., Medicaid State buy-in coverage or not). More disabled dually eligible beneficiaries are younger, non-White, and in fee-for-service (FFS) than non-dually eligible beneficiaries. Disabled dually eligible beneficiaries experienced consiste...

It is well known that the category KHaus of compact Hausdorff spaces is dually equivalent to the category KRFrm of compact regular frames. By de Vries duality, KHaus is also dually equivalent to the category DeV of de Vries algebras, and so DeV is equivalent to KRFrm, where the latter equivalence can be described constructively through Booleanization. Our purpose here is to lift this circle of ...

Individuals eligible in both Medicaid and Medicare, the dually eligible enrollees, account for a disproportionate share of Medicaid utilization and payments. While comprising 14.7 percent of the Medicaid population, they accounted for 40.5 percent of Medicaid payments in 2002. Mean reimbursement for the dually eligible enrollees was nearly four times that of non-dually eligible Medicaid enrolle...

The variety \(\mathbb{DHMSH}\) of dually hemimorphic semi-Heyting algebras was introduced in 2011 by the second author as an expansion a dual hemimorphism. In this paper, we focus on from logical point view. paper presents extensive investigation logic corresponding to and its axiomatic extensions, along with equally universal algebraic study their semantics. Firstly, present Hilbert-style axio...

In any semigroup S, we say that elements a and b are left inverses of each other if a = aba, b = bab and a L b, in which case we write a γ b. Right inverses are defined dually with the notation δ. Set τ = δγ. We study the classes of semigroups in which τ has some of the usual properties of a relation. We also consider properties of (maximal) completely simple subsemigroups of S. In terms of the...