Because of non-convexities in the model, computing much of anything along the nondominated frontier of a large-scale (1000 to 3000 securities) portfolio selection problem with semi-continuous variables is a task that has not previously been achieved. But (a) given the speed at which the nondominated frontier of a classical portfolio problem can now be computed and (b) the possibility that there...

gC(μ) := { F0(C) Fμ(C) if Fμ(C) > 0 ; +∞ if Fμ(C) = 0. Then fC is an upper semicontinuous function: if μ ∈ SM is such that Fμ(C) > 0, then fC is continuous at point μ. Otherwise, fC(μ) = ∞ and fC is trivially upper semicontinuous at point μ. Clearly, one has G(μ) = infC∈C fC(μ) ; as an infimum of upper semicontinuous functions, it is itself upper semicontinuous, and therefore attains its maximu...

In this paper we study differentiability and semismoothness properties of functions defined as integrals of parameterized functions. We also discuss applications of the developed theory to the problems of shape-preserving interpolation, option pricing and semi-infinite programming.

Given f : X → R ∪ {+∞} a convex and lower semi-continuous function defined on a reflexive Banach space X, and L, a closed linear manifold of X over which f takes at least a real value, the aim of this note is to prove the following Baire category result: in the Euclidean setting, the set of affine functions dominated by f on L for which there is no dominated extension to X is always of first Ba...

The aim of this note is to show how various facts in classical topology connected with semicontinuous functions and the semicontinuous quasi-uniformity have their counterparts in pointfree topology. In particular, we introduce the localic semicontinuous quasi-uniformity, which generalizes the semicontinuous quasiuniformity of a topological space (known to be one of the most important examples o...

Since the introduction of the Parikh matrix mapping, its injectivity problem is on top of the list of open problems in this topic. In 2010 Salomaa provided a solution for the ternary alphabet in terms of a Thue system with an additional feature called counter. This paper proposes the notion of a Parikh rewriting system as a generalization and systematization of Salomaa’s result. It will be show...