Displaying 81 – 100 of 138

Showing per page

Populational adaptive evolution, chemotherapeutic resistance and multiple anti-cancer therapies

Alexander Lorz, Tommaso Lorenzi, Michael E. Hochberg, Jean Clairambault, Benoît Perthame (2013)

ESAIM: Mathematical Modelling and Numerical Analysis - Modélisation Mathématique et Analyse Numérique

Resistance to chemotherapies, particularly to anticancer treatments, is an increasing medical concern. Among the many mechanisms at work in cancers, one of the most important is the selection of tumor cells expressing resistance genes or phenotypes. Motivated by the theory of mutation-selection in adaptive evolution, we propose a model based on a continuous variable that represents the expression level of a resistance gene (or genes, yielding a phenotype) influencing in healthy and tumor cells birth/death...

P-order necessary and sufficient conditions for optimality in singular calculus of variations

Agnieszka Prusińska, Alexey Tret'yakov (2010)

Discussiones Mathematicae, Differential Inclusions, Control and Optimization

This paper is devoted to singular calculus of variations problems with constraint functional not regular at the solution point in the sense that the first derivative is not surjective. In the first part of the paper we pursue an approach based on the constructions of the p-regularity theory. For p-regular calculus of variations problem we formulate and prove necessary and sufficient conditions for optimality in singular case and illustrate our results by classical example of calculus of variations...

Porosity and Variational Principles

Marchini, Elsa (2002)

Serdica Mathematical Journal

We prove that in some classes of optimization problems, like lower semicontinuous functions which are bounded from below, lower semi-continuous or continuous functions which are bounded below by a coercive function and quasi-convex continuous functions with the topology of the uniform convergence, the complement of the set of well-posed problems is σ-porous. These results are obtained as realization of a theorem extending a variational principle of Ioffe-Zaslavski.

Positivity and contractivity in the dynamics of clusters’ splitting with derivative of fractional order

Emile Franc Doungmo Goufo, Stella Mugisha (2015)

Open Mathematics

Classical models of clusters’ fission have failed to fully explain strange phenomenons like the phenomenon of shattering (Ziff et al., 1987) and the sudden appearance of infinitely many particles in some systems with initial finite particles number. Furthermore, the bounded perturbation theorem presented in (Pazy, 1983) is not in general true in solution operators theory for models of fractional order γ (with 0 < γ ≤ 1). In this article, we introduce and study a model that can be understood as...

Preface

Zbigniew Bartosiewicz, Ewa Girejko (2006)

Control and Cybernetics

Preface

Alexander Ioffe, Kazimierz Malanowski, Fredi Tröltzsch (2009)

Control and Cybernetics

Preface

Alexander Ioffe, Kazimierz Malanowski, Fredi Tröltzsch (2009)

Control and Cybernetics

Preface

Ronald Hoppe, Karl Kunisch, Jan Sokołowski, Antoni Żochowski (2010)

Control and Cybernetics

Prékopa–Leindler type inequalities on Riemannian manifolds, Jacobi fields, and optimal transport

Dario Cordero-Erausquin, Robert J. McCann, Michael Schmuckenschläger (2006)

Annales de la faculté des sciences de Toulouse Mathématiques

We investigate Prékopa-Leindler type inequalities on a Riemannian manifold M equipped with a measure with density e - V where the potential V and the Ricci curvature satisfy Hess x V + Ric x λ I for all x M , with some λ . As in our earlier work [14], the argument uses optimal mass transport on M , but here, with a special emphasis on its connection with Jacobi fields. A key role will be played by the differential equation satisfied by the determinant of a matrix of Jacobi fields. We also present applications of the method...

Pricing rules under asymmetric information

Shigeyoshi Ogawa, Monique Pontier (2007)

ESAIM: Probability and Statistics

We consider an extension of the Kyle and Back's model [Back, Rev. Finance Stud.5 (1992) 387–409; Kyle, Econometrica35 (1985) 1315–1335], meaning a model for the market with a continuous time risky asset and asymmetrical information. There are three financial agents: the market maker, an insider trader (who knows a random variable V which will be revealed at final time) and a non informed agent. Here we assume that the non informed agent is strategic, namely he/she uses a utility function to...

Primal interior point method for minimization of generalized minimax functions

Ladislav Lukšan, Ctirad Matonoha, Jan Vlček (2010)

Kybernetika

In this paper, we propose a primal interior-point method for large sparse generalized minimax optimization. After a short introduction, where the problem is stated, we introduce the basic equations of the Newton method applied to the KKT conditions and propose a primal interior-point method. (i. e. interior point method that uses explicitly computed approximations of Lagrange multipliers instead of their updates). Next we describe the basic algorithm and give more details concerning its implementation...

Currently displaying 81 – 100 of 138