On the interplay of harvesting and various diffusion strategies for spatially heterogeneous populations.

The paper explores the influence of harvesting (or culling) on the outcome of the competition of two species in a spatially heterogeneous environment. The harvesting effort is assumed to be proportional to the space-dependent intrinsic growth rate. The differences between the two populations are the diffusion strategy and the harvesting intensity.

Stabilization of Structured Populations via Vector Target-Oriented Control.

In contrast with unstructured models, structured discrete population models have been able to fit and predict chaotic experimental data. However, most of the chaos control techniques in the literature have been designed and analyzed in a one-dimensional setting. Here, by introducing target-oriented control for discrete dynamical systems, we prove the possibility to stabilize a chosen state for a wide range of structured population models.

Effect of treatment on the global dynamics of delayed pathological angiogenesis models.

For three different types of angiogenesis models with variable delays, we consider either continuous or impulse therapy that eradicates tumor cells and suppresses angiogenesis. For the cancer-free solution, explicit conditions of global stability for the continuous and impulsive systems are obtained, together with delay-dependent estimates for the rates of decay for the tumor volume and pathological angiogenesis.

Velocity-dependent cost function for the prediction of force sharing among synergistic muscles in a one degree of freedom model.

Prediction of accurate and meaningful force sharing among synergistic muscles is a major problem in biomechanics research. Given a resultant joint moment, a unique set of muscle forces can be obtained from this mathematically redundant system using nonlinear optimization. The classical cost functions for optimization involve a normalization of the muscle forces to the absolute force capacity of the target muscles, usually by the cross-sectional area or the maximal isometric force.

Continuous versus pulse harvesting for population models in constant and variable environment.

We consider both autonomous and nonautonomous population models subject to either impulsive or continuous harvesting. It is demonstrated in the paper that the impulsive strategy can be as good as the continuous one, but cannot outperform it. We introduce a model, where certain harm to the population is incorporated in each harvesting event, and study it for the logistic and the Gompertz laws of growth.

On linear perturbations of the Ricker model.

A class of linearly perturbed discrete-time single species scramble competition models, like the Ricker map, is considered. Perturbations can be of both recruitment and harvesting types. Stability (bistability) is considered for models, where parameters of the map do not depend on time.