I will review RHIC data with respect to the intriguing possibility that the hadron production mechanism in the produced partonic medium might be different than in vacuum. I will use the measurements of collective features, such as flow and quenching of identified particles, to show that different regions of the particle momentum spectrum are likely populated through different mechanisms, and th...

Let f : M →M be a continuous map of a locally compact metric space. Models of interacting populations often have a closed invariant set ∂M that corresponds to the loss or extinction of one or more populations. The dynamics of f subject to bounded random perturbations for which ∂M is absorbing are studied. When these random perturbations are sufficiently small, almost sure absorbtion (i.e. extin...

The population dynamics of predator-prey systems in the presence of patch-specific predators are explored in a setting where the prey population has access to both habitats. The emphasis is in situations where patch-prey abundance drives prey-dispersal between patches, with the fragile prey populations, that is, populations subject to the Alee effect. The resulting four-dimensional model’s math...

It is widely believed that greater initial population diversity leads to improved performance in genetic algorithms. However, this assumption has not been rigorously tested previously. We put this assumption to the test on two benchmark problems and found that greater diversity did not lead to improved performance. This result will require a serious rethinking on the part of the evolutionary co...

It is widely accepted that there is a strong correlation between diversity in the initial population and Genetic Algorithms’ performance. One contribution of this paper is to show that there is not such a strong correlation between diversity and Genetic Algorithms’ performance, at least with the standard range of diversity measures used in a randomly generated population and with the misuse det...

Population dynamics are almost inevitably associated with two predominant sources of variation: the first, demographic variability, a consequence of chance in progenitive and deleterious events; the second, initial state uncertainty, a consequence of partial observability and reporting delays and errors. Here we outline a general method for incorporating random initial conditions in population ...

Assigning a set of objects to groups such that objects in one group or cluster are more similar to each other than the other clusters’ objects is the main task of clustering analysis. SSPCO optimization algorithm is anew optimization algorithm that is inspired by the behavior of a type of bird called see-see partridge. One of the things that smart algorithms are applied to solve is the problem ...