“Security” parallels “health” in that it is commonly defined as the absence of its negation, “illness”. In fact, the concept of security challenges any attempt to be objectively apprehended, except as an absence of insecurity. Illness, however, can be identified wherever and whenever by sets of visible symptoms that are indicators of regularities, usually bringing forth the same effects. This i...

The Yule-Nielsen modified spectral Neugebauer model enables predicting reflectance spectra from surface coverages. In order to provide high prediction accuracy, this model is enhanced with an ink spreading model accounting for physical dot gain. Traditionally, physical dot gain, also called mechanical dot gain, is modeled by one ink spreading curve per ink. An ink spreading curve represents the...

We define tropical Psi-classes on M 0,n (R 2 , d) and consider intersection products of Psi-classes and pull-backs of evaluations on this space. We show a certain WDVV equation which is sufficient to prove that tropical numbers of curves satisfying certain Psi-and evaluation conditions are equal to the corresponding classical numbers. We present an algorithm that generalizes Mikhalkin's lattice...

Positivity preserving properties have been conjectured for the bilaplace Dirichlet problem in many versions. In this note we show that in any dimension there exist bounded smooth domains Ω such that even the solution of ∆u = 1 in Ω with the homogeneous Dirichlet boundary conditions u = uν = 0 on ∂Ω is sign-changing. In two dimensions this corresponds to the Kirchhoff-Love model of a clamped pla...

Abstract. We analyse dissipative boundary conditions for nonlinear hyperbolic systems in one space dimension. We show that a known sufficient condition for exponential stability with respect to the H-norm is not sufficient for the exponential stability with respect to the C-norm. Hence, due to the nonlinearity, even in the case of classical solutions, the exponential stability depends strongly ...

In this paper we study a continuous time, optimal stochastic investment problem under limited resources in a market with N firms. The investment processes are subject to a time-dependent stochastic constraint. Rather than using a dynamic programming approach, we exploit the concavity of the profit functional to derive some necessary and sufficient first order conditions for the corresponding So...

This paper studies first order conditions (Karush–Kuhn–Tucker conditions) for discretized optimal control problems with nonsmooth constraints. We present a simple condition which can be used to verify that a local optimal point satisfies the first order conditions and that a point satisfying the first order conditions is a global or local optimal solution of the optimal control problem.

The aim of this paper is to present a short survey of several new results concerning optimization of discrete inclusions. We study an optimization problem given by a discrete inclusion with end point constraints and we present several approaches concerning first and secondorder necessary optimality conditions for this problem.

We prove in the Tucker-Wang approach to non-Riemannian Gravity that a general homogeneous Lagrangian density in the general connection with order of homogeneity of at least two gives no contribution to the generalised Einstein equations. Using this result other important cases are also considered. 04.20.-q, 04.40.-b, 04.50.+h, 04.62.+v [email protected]

Modeling the dynamics of infectious diseases, illicit drug initiation, or other systems, where the age of an individual or the duration of being in a specific state is essential, leads to a generalized form of the McKendrick equations, i.e., a system of first-order partial differential equations in the time-age space. Typically such models include agespecific feedback components which are repre...