Vaccination in a model of an epidemic.
Vaccination strategies of population groups with distinct perceived probabilities of infection.
Variances in spectral analysis of membrane noise
Le fluttuazioni di conduttanza di un modello di canale del potassio di una fibra muscolare che segue una cinetica di Hodgkin e Huxley sono state analizzate attraverso l'analisi spettrale indiretta. Sono state confrontate due diverse stime della densità spettrale e le loro rispettive varianze: quella della prima stima considerata è già nota, mentre quella della seconda stima è stata ricavata da noi nelle medesime ipotesi (distribuzione normale). I risultati teorici sono stati confrontati con quelli...
Varianta modelu biologického neuronu podle N. I. Vvedenského
Variation de la concentration plasmatique d'une substance au cours d'une perfusion et après celle-ci ; cas du dinitrate d'isosorbide
Variational Framework for Assessment of the Left Ventricle Motion
Impairment of left ventricular contractility due to cardiovascular diseases is reflected in left ventricle (LV) motion patterns. An abnormal change of torsion or long axis shortening LV values can help with the diagnosis and follow-up of LV dysfunction. Tagged Magnetic Resonance (TMR) is a widely spread medical imaging modality that allows estimation of the myocardial tissue local deformation. In this work, we introduce a novel variational framework for extracting the left ventricle dynamics from...
Variational Reduction for the Transport Equation in a Multiple Branching Plants Growth Model
Plant growth depends essentially on nutrients coming from the roots and metabolites produced by the plant. Appearance of new branches is determined by concentrations of certain plant hormones. The most important of them are Auxin and Cytokinin. Auxin is produced in the growing, Cytokinin in either roots or in growing parts. Many dynamical models of this phenomena have been studied in [1]. In [5], the authors deal with one branch model. In this work,...
Verified solution method for population epidemiology models with uncertainty
Epidemiological models can be used to study the impact of an infection within a population. These models often involve parameters that are not known with certainty. Using a method for verified solution of nonlinear dynamic models, we can bound the disease trajectories that are possible for given bounds on the uncertain parameters. The method is based on the use of an interval Taylor series to represent dependence on time and the use of Taylor models to represent dependence on uncertain parameters...
Viability, invariance and reachability for controlled piecewise deterministic Markov processes associated to gene networks
We aim at characterizing viability, invariance and some reachability properties of controlled piecewise deterministic Markov processes (PDMPs). Using analytical methods from the theory of viscosity solutions, we establish criteria for viability and invariance in terms of the first order normal cone. We also investigate reachability of arbitrary open sets. The method is based on viscosity techniques and duality for some associated linearized problem. The theoretical results are applied to general...
Viability, invariance and reachability for controlled piecewise deterministic Markov processes associated to gene networks
We aim at characterizing viability, invariance and some reachability properties of controlled piecewise deterministic Markov processes (PDMPs). Using analytical methods from the theory of viscosity solutions, we establish criteria for viability and invariance in terms of the first order normal cone. We also investigate reachability of arbitrary open sets. The method is based on viscosity techniques and duality for some associated linearized problem. The theoretical results are applied to general...
Viability, invariance and reachability for controlled piecewise deterministic Markov processes associated to gene networks
We aim at characterizing viability, invariance and some reachability properties of controlled piecewise deterministic Markov processes (PDMPs). Using analytical methods from the theory of viscosity solutions, we establish criteria for viability and invariance in terms of the first order normal cone. We also investigate reachability of arbitrary open sets. The method is based on viscosity techniques and duality for some associated linearized problem. The theoretical results are applied to general...
Vibration attenuation in rotating machines using smart spring mechanism.
Vingt analyses multivariées d'une structure connue
L'usage croissant des analyses multivariées modifie la méthode de plusieurs sciences sociales. Le débat sur leur validité est toutefois assez confus car des questions de pure mathématique se mélangent à des problèmes perceptifs (représentation) et logiques (modélisation). Nous n'avons actuellement ni les moyens ni l'ambition d'aborder théoriquement leur statut, mais nous pensons fournir un document utile au débat en appliquant la majorité des méthodes à un même objet déjà connu et en comparant leur...
Visual measurement of suture strain for robotic surgery.
Volume Filling Effect in Modelling Chemotaxis
The oriented movement of biological cells or organisms in response to a chemical gradient is called chemotaxis. The most interesting situation related to self-organization phenomenon takes place when the cells detect and response to a chemical which is secreted by themselves. Since pioneering works of Patlak (1953) and Keller and Segel (1970) many particularized models have been proposed to describe the aggregation phase of this process. Most of...
Von Bertalanffy's growth dynamics with strong Allee effect
Von Bertalanffy’s model is one of the most popular differential equation used in order to study the increase in average length or weight of fish. However, this model does not include demographic Allee effect. This phenomenon is known in the fisheries literature as “depensation”, which arises when populations decline rapidly at low densities. In this paper we develop and investigate new corrected von Bertalanffy’s models with Allee effects. The generalization that we propose results from considering...