In this paper, we make use of the Sobolev space W 1,1 (R+, Rn) to derive at once the Pontryagin conditions for the standard optimal growth model in continuous time, including a necessary and sufficient transversality condition. An application to the Ramsey model is given. We use an order ideal argument to solve the problem inherent to the fact that L1 spaces have natural positive cones with no ...

In this article, the sufficient Pontryagin’s maximum principle for infinite horizon discounted stochastic control problem is established. The sufficiency is ensured by an additional assumption of concavity of the Hamiltonian function. Throughout the paper, it is assumed that the control domain U is a convex set and the control may enter the diffusion term of the state equation. The general resu...

Bacterial tolerance to antibiotics is a well-known phenomena; however, only recent studies of bacterial biofilms have shown how multifaceted tolerance really is. By joining into a structured community and offering shared protection and gene transfer, bacterial populations can protect themselves genotypically, phenotypically and physically. In this study, we collect a line of research that focus...

Understanding social inequalities in health is of great importance; it provides the conceptual frame for investigating the social factors that affect health, together with empirical evidence for improving population health. Individual and socioeconomic data, disease related conditions and self rated health (SRH) ratings were collected from a representative sample of 1,000 participants in order ...

This article sets out to examine the perceptions regarding the sustainability of organizations within the Nelson Mandela Bay region in South Africa. The integration of economic, social and environmental performance seems to be an obstacle to many organizations. Not many organizations pursue a sustainability agenda full-on and lack a vision of sustainability, thus needing appropriate change stra...

The paper presents necessary optimality conditions of Pontryagin’s type for infinite-horizon optimal control problems for age-structured systems with stateand control-dependent boundary conditions. Despite the numerous applications of such problems in population dynamics and economics, a “complete” set of optimality conditions is missing in the existing literature, because it is problematic to ...

This paper considers demand side management in smart power grid systems containing significant numbers of thermostatically controlled loads such as air conditioning systems, heat pumps, etc. Recent studies have shown that the overall power consumption of such systems can be regulated up and down centrally by broadcasting small setpoint change commands without significantly impacting consumer co...

The paper is an overview of our recent results achieved with different coauthors, concerning several research lines of applied population dynamics we initiated some years ago, and mostly published in 2010. First, based on the classical Leslie population model, a dynamic demographic model including controlled immigration is recalled, and applying the Perron-Frobenius theory of nonnegative matric...

We develop the theory of optimal control for a system of integrodifference equations modelling a pest-pathogen system. Integrodifference equations incorporate continuous space into a system of discrete time equations. We design an objective functional to minimize the damaged cost generated by an invasive species and the cost of controlling the population with a pathogen. Existence, characteriza...

The causes of cancer health disparities amongst Pacific Islanders and other racial groups are complex and multifactorial. Both biologic and non biologic determinants have been identified as causal factors. Racial/ethnic classification can be used as a surrogate for non biologic determinants such as place of geographic origin, socioeconomic status, cultural practices, and diet. Given that non bi...