In this paper, the concept of {sl local base with  stratifiedstructure} in $I$-topological vector spaces is introduced. Weprove that every $I$-topological vector space has a balanced localbase with stratified structure. Furthermore, a newcharacterization of $I$-topological vector spaces by means of thelocal base with stratified structure is given.

of n linearly independent vectors b1, . . . ,bn ∈ Rm in m-dimensional Euclidean space. For computational purposes, the lattice vectors b1, . . . ,bn are often assumed to have integer (or rational) entries, so that the lattice can be represented by an integer matrix B = [b1, . . . ,bn] ∈ Zm×n (called basis) having the generating vectors as columns. Using matrix notation, lattice points in L(B) c...

We show a strong indication of the existence of a large Fermi surface in the one-dimensional Kondo lattice model. The characteristic wave vector of the model is found to be k F = (1 + ρ)π/2, ρ being the density of the conduction electrons. This result is at first obtained for a variant of the model that includes an antiferromagnetic Heisenberg interaction J H between the local moments. It is th...

We investigate the duality between algebraic and coalgebraic recognition of languages to derive a generalization of the local version of Eilenberg’s theorem. This theorem states that the lattice of all boolean algebras of regular languages over an alphabetΣ closed under derivatives is isomorphic to the lattice of all pseudovarieties ofΣ-generated monoids. By applying our method to different cat...