We compute all the relations in cohomology satisfied by the elements of degree two of H∗(Un(Fp), Z) where p ≥ n and Un(Fp) is the group of of upper triangular matrices of GLn(Fp) with 1 on the main diagonal. e-mail: [email protected]

Department of Computer Science, K.U.Leuven Celestijnenlaan 200A B-3001 Heverlee, Belgium In this talk we investigate some matrix structures on Cn×n that have a good behaviour under matrix inversion. The first kind of structure is strongly related to low displacement rank structure. The second kind of structure deals with certain low rank submatrices. In this case, it can be shown that also the ...

Temporal and spatio-temporal data are present in many modern application systems, including monitoring moving objects. Such systems produce enormous volume of data, and therefore efficient indexing method is crucial. In this paper, we investigate and present a new concept based on virtual index structure, which can efficiently query such data. Concept is based on spatial representation of inter...

where τ0 = 1. The τ -functions τn are given by the pfaffians of certain skew-symmetric matrix. We identify one-soliton solution as an element of the Weyl group of D-type, and discuss a general structure of the interaction patterns among the solitons. Soliton solutions are characterized by 4N × 4N skew-symmetric constant matrix which we call the B-matrices. We then find that one can have M -soli...

In this paper, left derivations and Jordan left derivations in full and upper triangular matrix rings over unital associative rings are characterized.

We consider positive entropy G-systems for certain countable, discrete, infinite left-orderable amenable groups G. By undertaking local analysis, the existence of asymptotic pairs and chaotic sets will be studied in connecting with the stable sets. Examples are given for the case of integer lattice groups, the Heizenberg group, and the groups of integral unipotent upper triangular matrices.

We characterize T-measures on weakly generated tribes, where T is a strict triangular norm and we give a Liapunoff Theorem for these measures. This generalizes previous results obtained for monotonic T-measures or for Frank triangular norms.

The fine spectra of lower triangular double-band matrices were examined by several authors. Here we determine the fine spectra of upper triangular double-band matrices over the sequence spaces () p and () bv p. Upper triangular double-band matrices are infinite matrices which include the left-shift, averaging and difference operators.

a watching system in a graph $g=(v, e)$ is a set $w={omega_{1}, omega_{2}, cdots, omega_{k}}$, where $omega_{i}=(v_{i}, z_{i}), v_{i}in v$ and $z_{i}$ is a subset of closed neighborhood of $v_{i}$ such that the sets $l_{w}(v)={omega_{i}: vin omega_{i}}$ are non-empty and distinct, for any $vin v$. in this paper, we study the watching systems of line graph $k_{n}$ which is called triangular grap...