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Bifurcation Thresholds in an SIR Model with Information-Dependent Vaccination

A. d'Onofrio, P. Manfredi, P. Manfredi (2010)

Mathematical Modelling of Natural Phenomena

Simple epidemiological models with information dependent vaccination functions can generate sustained oscillations via Hopf bifurcation of the endemic state. The onset of these oscillations depend on the shape of the vaccination function. A “global” approach is used to characterize the instability condition and identify classes of functions that always lead to stability/instability. The analysis allows the identification of an analytically determined “threshold vaccination function” having...

Bilinear system as a modelling framework for analysis of microalgal growth

Štěpán Papáček, Sergej Čelikovský, Dalibor Štys, Javier Ruiz (2007)

Kybernetika

A mathematical model of the microalgal growth under various light regimes is required for the optimization of design parameters and operating conditions in a photobioreactor. As its modelling framework, bilinear system with single input is chosen in this paper. The earlier theoretical results on bilinear systems are adapted and applied to the special class of the so-called intermittent controls which are characterized by rapid switching of light and dark cycles. Based on such approach, the following...

Building Mathematical Models and Biological Insight in an Introductory Biology Course

A. E. Weisstein (2011)

Mathematical Modelling of Natural Phenomena

A growing body of literature testifies to the importance of quantitative reasoning skills in the 21st-century biology curriculum, and to the learning benefits associated with active pedagogies. The process of modeling a biological system provides an approach that integrates mathematical skills and higher-order thinking with existing course content knowledge. We describe a general strategy for teaching model-building in an introductory biology course,...

Building the library of RNA 3D nucleotide conformations using the clustering approach

Tomasz Zok, Maciej Antczak, Martin Riedel, David Nebel, Thomas Villmann, Piotr Lukasiak, Jacek Blazewicz, Marta Szachniuk (2015)

International Journal of Applied Mathematics and Computer Science

An increasing number of known RNA 3D structures contributes to the recognition of various RNA families and identification of their features. These tasks are based on an analysis of RNA conformations conducted at different levels of detail. On the other hand, the knowledge of native nucleotide conformations is crucial for structure prediction and understanding of RNA folding. However, this knowledge is stored in structural databases in a rather distributed form. Therefore, only automated methods...

Cálculo de probabilidades en el análisis de perfiles genéticos compatibles.

Miguel Sánchez García, Pedro Cuesta Alvaro (2000)

Qüestiió

Un hecho delictivo ha sido cometido por una o más personas. Para descubrir el número de presuntos delincuentes, se determina el perfil genético de la evidencia forense encontrada en el lugar del delito, mediante el estudio de marcadores de tipo STR. En el presente artículo se desarrollan diversos algoritmos. En el primero se considera la probabilidad de que n personas elegidas aleatoriamente de la población de referencia contengan un perfil genético compatible, en el segundo se calcula la evidencia...

Canonical non-symmetrical correspondence analysis: an alternative in constrained ordination.

Priscila Willems, M. Purificación Galindo Villardon (2008)

SORT

Canonical non-symmetrical correspondence analysis is developed as an alternative method for constrained ordination, relating external information (e.g., environmental variables) with ecological data, considering species abundance as dependant on sites. Ordination axes are restricted to be linear combinations of the environmental variables, based on the information of the most abundant species. This extension and its associated unconstrained ordination method are terms of a global model that permits...

Cell Modelling of Hematopoiesis

N. Bessonov, L. Pujo-Menjouet, V. Volpert (2010)

Mathematical Modelling of Natural Phenomena

In this work, we introduce a new software created to study hematopoiesis at the cell population level with the individually based approach. It can be used as an interface between theoretical works on population dynamics and experimental observations. We show that this software can be useful to study some features of normal hematopoiesis as well as some blood diseases such as myelogenous leukemia. It is also possible to simulate cell communication and the formation of cell colonies in the bone marrow. ...

Codings and operators in two genetic algorithms for the leaf-constrained minimum spanning tree problem

Bryant Julstrom (2004)

International Journal of Applied Mathematics and Computer Science

The features of an evolutionary algorithm that most determine its performance are the coding by which its chromosomes represent candidate solutions to its target problem and the operators that act on that coding. Also, when a problem involves constraints, a coding that represents only valid solutions and operators that preserve that validity represent a smaller search space and result in a more effective search. Two genetic algorithms for the leaf-constrained minimum spanning tree problem illustrate...

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