We simulate the swarming behavior of three synthetic animal species that differ only by the degree of perception they have on their fellow animals. The species are called mosquitoes, birds and fish. The swarms that comprise many individuals of each species in turn move randomly in a rugged potential landscape. The mosquitoes pay no heed to one another. The birds follow a bunch of their nearest ...

The interrelationships of the fundamental biological processes natural selection, mutation, and stochastic drift are quantified by the entropy rate of Moran processes with mutation, measuring the long-run variation of a Markov process. The entropy rate is shown to behave intuitively with respect to evolutionary parameters such as monotonicity with respect to mutation probability (for the neutra...

We present a fractal technique for addressing geometric analogy problems from the Raven's Standard Progressive Matrices test of general intelligence. In this method, an image is represented fractally, capturing its inherent selfsimilarity. We apply these fractal representations to problems from the Raven's test, and show how these representations afford a new method for solving complex geometri...

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We investigate the influence of fractal structure on material properties. We calculate the statistical correlation functions of fractal media defined by level-cut Gaussian random fields. This allows the modeling of both surface fractal and mass fractal materials. Variational bounds on the conductivity, diffusivity and elastic moduli of the materials are evaluated. We find that a fractally rough...

Geographers have been reticent on the role of the African diaspora in the contouring of Brazil’s biological and cultural landscapes. Whereas paradigm shifts have occurred in regards to environmental stability in the tropical realm and the pristine nature of pre-Columbian landscapes, these have not translated to a rigorous reassessment of the geographical position of Africans and their descendan...

We specify a system of equations that fully reflects the supply and demand sides of the market for agricultural open space at equilibrium. Although simple, the system is exceedingly flexible and allows for household and parcel heterogeneity. We derive an empirical model directly from the structural equations and contrast this using a simulated landscape with the econometric specification most o...

The main purpose of this study is to derive forest recreation demand in Jizerske Mountains Protected Landscape Area and to disentangle aesthetic factors that are responsible for changes in recreation utility of visitors. We estimate visitors’ preferences for alternative forest sites as a function of site characteristics using choice experiment technique. As forest scenic beauty may represent a ...