The Bidirectional Texture Function (BTF) is the recent most advanced representation of visual properties of surface materials. It specifies their appearance due to varying spatial, illumination, and viewing conditions. Corresponding enormous BTF measurements require a mathematical representation allowing extreme compression but simultaneously preserving its high visual fidelity. We present a no...

In the following, M,M denote respectively the set of all products of matrices in M, and the set of all products of length t of matrices in M. This problem is closely related to the so called joint spectral subradius of a set of matrices, which is the smallest asymptotic rate of growth of any long product of matrices in the set, when the length of the product increases. For a survey on the joint...

Knowledge of the scene illuminant spectral power distribution is useful for many imaging applications, such as color image reproduction and automatic algorithms for image database applications. In many applications accurate spectral characterization of the illuminant is impossible because the input device acquires only three spectral samples. In such applications it is sensible to set a more li...

Aalto University, P.O. Box 11000, FI-00076 Aalto www.aalto.fi Author Olavi Nevanlinna Name of the publication Multicentric representation and von Neumann spectral sets Publisher School of Science Unit Department of Mathematics and Systems Analysis Series Aalto University publication series SCIENCE + TECHNOLOGY 11/2011 Field of research Mathematics Abstract We show how multicentric representatio...

We study spectral triples on (weighted) groups and consider functors between the categories of weighted groups and spectral triples. We study the properties of weights and the corresponding functor for spectral triples coming from discrete weighted groups.

In this paper, a novel and noise robust front-end based on the combined application of spectral subtraction, spectral flooring and cumulative distribution mapping is proposed. Recognition experiments with the Aurora II connected digits reveal that the proposed front-end achieves an average digit accuracy of 81.46% for a model set trained from clean data and 89.54% for a model set trained from d...

lexicographic ordering by spectral moments ($s$-order) among all trees is discussed in this‎ ‎paper‎. ‎for two given positive integers $p$ and $q$ with $pleqslant q$‎, ‎we denote $mathscr{t}_n^{p‎, ‎q}={t‎: ‎t$ is a tree of order $n$ with a $(p‎, ‎q)$-bipartition}‎. furthermore, ‎the last four trees‎, ‎in the $s$-order‎, ‎among $mathscr{t}_n^{p‎, ‎q},(4leqslant pleqslant q)$ are characterized‎.

in this paper some upper and lower bounds for the greatest eigenvalues of the pi and vertex pimatrices of a graph g are obtained. those graphs for which these bounds are best possible arecharacterized.