We survey the recent mathematical results about aging in certain simple disordered models. We start by the Bouchaud trap model. We then survey the results obtained for simple models of spin-glass dynamics, like the REM (the Random Energy Model, which is well approximated by the Bouchaud model on the complete graph), then the spherical Sherrington-Kirkpatrick model. We will insist on the differe...

In this paper, the matrix extension of the multivariable Humbert polynomials is introduced. Various families of linear, multilinear and multilateral generating matrix functions of these matrix polynomials are presented. Miscellaneous applications are also discussed. 2000 Mathematics Subject Classification: 33C25; 15A60

We generalise a method of Xiao Gang to construct ’prototypes’ of fibred surfaces with maximal irregularity without being a product. This enables us, in the case of fibre genus g = 3 to describe the possible singular fibres and to calculate the invariants of these surfaces. We also prove structure theorems on the moduli space for fibred surfaces with fibre genus g = 2 and g = 3. Mathematics Subj...

Date: September 2, 2008. 2000 Mathematics Subject Classification. 42C40, 43A65,43A70.

The mean transformations M(A,B) are linear mappings and they are analogues of the matrix means of A,B ≥ 0. They are defined by operator monotone functions. In this paper several properties are described and a part of them characterize the concept. 2000 Mathematics Subject Classification. Primary 26E60; Secondary 15A45.

Uncovering the right skills behind question items is a difficult task. It requires a thorough understanding of the subject matter and of the cognitive factors that determine student performance. The skills definition, and the mapping of item to skills, require the involvement of experts. We investigate means to assist experts for this task by using a data driven, matrix factorization approach. ...

In recent years, a number of authors have started studying Aristotelian diagrams containing metalogical notions, such as tautology, contradiction, satisfiability, contingency, strong and weak interpretations of (sub)contrariety, etc. The present paper is a contribution to this line of research, and its main aims are both to extend and to deepen our understanding of metalogical diagrams. As for ...

In this paper some new Hardy–type inequalities on time scales are derived and proved using the concept of superquadratic functions. Also, we extend Hardy–type inequalities involving superquadratic functions with general kernels to the case with arbitrary time scales. Several consequences of our results are given and their connection with recent results in the literature are pointed out and disc...