Analytical investigation of the onset of bifurcation cascade in two logistic-like maps.
Analyzing sets of phylogenetic trees using metrics
The reconstruction of evolutionary trees is one of the primary objectives in phylogenetics. Such a tree represents historical evolutionary relationships between different species or organisms. Tree comparisons are used for multiple purposes, from unveiling the history of species to deciphering evolutionary associations among organisms and geographical areas. In this paper, we describe a general method for comparing phylogenetic trees and give some basic properties of the Matching Split metric, which...
Analyzing the dynamics of deterministic systems from a hypergraph theoretical point of view
To model the dynamics of discrete deterministic systems, we extend the Petri nets framework by a priority relation between conflicting transitions, which is encoded by orienting the edges of a transition conflict graph. The aim of this paper is to gain some insight into the structure of this conflict graph and to characterize a class of suitable orientations by an analysis in the context of hypergraph theory.
Ancestral processes with selection: Branching and Moran models
We consider two versions of stochastic population models with mutation and selection. The first approach relies on a multitype branching process; here, individuals reproduce and change type (i.e., mutate) independently of each other, without restriction on population size. We analyse the equilibrium behaviour of this model, both in the forward and in the backward direction of time; the backward point of view emerges if the ancestry of individuals chosen randomly from the present population is traced...
Angiogenesis process with vessel impairment for Gompertzian and logistic type of tumour growth
We propose two models of vessel impairment in the process of tumour angiogenesis and we consider three types of treatment: standard chemotherapy, antiangiogenic treatment and a combined treatment. The models are based on the idea of Hahnfeldt et al. that the carrying capacity for any solid tumour depends on its vessel density. In the models proposed the carrying capacity also depends on the process of vessel impairment. In the first model a logistic type equation is used to describe the neoplastic...
Anti-periodic solutions for high-order cellular neural networks with time-varying delays.
Anti-periodic solutions for recurrent neural networks without assuming global Lipschitz conditions.
Apparition de motifs géométriques dans une membrane enzymatique
Application des sentinelles à l'identification des pollutions dans une rivière
Application of a new processing method to post-LDL-apheresis data.
Application of Cauchy's equation in combinatorics and genetics.
Application of coupled neural oscillators for image texture segmentation and modeling of biological rhythms
The role of relaxation oscillator models in application fields such as modeling dynamic systems and image analysis is discussed. A short review of the Van der Pol, Wilson-Cowan and Terman-Wang relaxation oscillators is given. The key property of such nonlinear oscillators, i.e., the oscillator phase shift (called the Phase Response Curve) as a result of external pulse stimuli is indicated as a fundamental mechanism to achieve and sustain synchrony in networks of coupled oscillators. It is noted...
Application of discriminant, classification tree and neural network analysis to differentiate between potential glaucoma suspects with and without visual field defects.
Application of Hybrid Models to Blood Cell Production in the Bone Marrow
A hybrid model of red blood cell production, where cells are considered as discrete objects while intra-cellular proteins and extra-cellular biochemical substances are described with continuous models, is proposed. Spatial organization and regulation of red blood cell production (erythropoiesis) are investigated. Normal erythropoiesis is simulated in two dimensions, and the influence on the output of the model of some parameters involved in cell...
Application of Neural Networks to Modal Split Modelling
Application of Neural-Net Computing to Transient Stability Assessment and Enhancement of Electric Power Systems
Application of occupancy and ordering theory in genetics of autopolyploids
Application of the adaptive center-weighted vector median framework for the enhancement of cDNA microarray images
In this paper a novel method of noise reduction in color images is presented. The new technique is capable of attenuating both impulsive and Gaussian noise, while preserving and even enhancing the sharpness of the image edges. Extensive simulations reveal that the new method outperforms significantly the standard techniques widely used in multivariate signal processing. In this work we apply the new noise reduction method for the enhancement of the images of the so called gene chips. We demonstrate...
Application of the Monte Carlo method for the assessment of long-term success in keratoprosthesis surgery.
Application of the random field theory in PET imaging - injection dose optimization
This work presents new application of the random field theory in medical imaging. Results from both integral geometry and random field theory can be used to detect locations with significantly increased radiotracer uptake in images from positron emission tomography (PET). The assumptions needed to use these results are verified on a set of real and simulated phantom images. The proposed method of detecting activation (locations with increased radiotracer concentration) is used to quantify the quality...