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The spatiotemporal behavior of the spread of influenza in France has been studied, and algebraic spatial correlations (with exponent ) spanning the whole territory have been found to be present as soon as the number of reported cases first starts to increase, about 15 to 25 weeks before the peak...
Persistent link: https://www.econbiz.de/10005623653
Morphospace studies are rich in pattern and process. Techniques for adequate description and mapping of morphologies have been increasingly refined and applied, the same being true of metrics for relevant parameters (like disparity). However, the testing of process hypotheses for specific...
Persistent link: https://www.econbiz.de/10005623654
We present a simple model of a vibrated box of sand, and discuss its dynamics in terms of two parameters reflecting static and dynamic disorder respectively. The fluidised, intermediate and frozen (`glassy') dynamical regimes are extensively probed by analysing the response of the packing...
Persistent link: https://www.econbiz.de/10005623655
We study topological defects in the triangular Ising antiferromagnet, a related model on the square lattice equivalent to the six-vertex ice model, and the three-state antiferromagnetic Potts model on the square lattice. We suggest that in each case, defects are attracted or repelled with a...
Persistent link: https://www.econbiz.de/10005623656
Many natural systems, as social insects, perform complex computations collectively. In these groups, large numbers of individuals communicate in a local way and send information to its nearest neighbors. Interestingly, a general observation of these societies reveals that the computational...
Persistent link: https://www.econbiz.de/10005623657
A model of biological morphogenesis is presented. The model is based in a gene-network cell description plus the interaction among cells. Here interactions between nearest cells are due to diffusion-like mechanisms and also to inductive, cell-to-cell interactions. The gene network properties are...
Persistent link: https://www.econbiz.de/10005623658
We consider sets of rectangles and squares recognized by deterministic and non-deterministic two-dimensional finite-state automata. We show that NFAs are strictly more powerful than DFAs, even for pictures over a one-symbol alphabet. In the process, we show that the pitcure languages recognized...
Persistent link: https://www.econbiz.de/10005623660
In many applications it is necessary to use a simple and therefore highly misspecified econometric model as the basis for decision-making. We propose an approach to developing a possibly misspecified econometric model that will be used as the beliefs of an objective expected utility maximiser. A...
Persistent link: https://www.econbiz.de/10005623661
We apply tiling groups and height functions to tilings of regions in the plane by Wang tiles, which are squares with colored boundaries where the colors of shared edges must match. We define a set of tiles as unambiguous if it contains all tiles equivalent to the identity in its tiling group....
Persistent link: https://www.econbiz.de/10005623662
Using data from computer databases of scientific papers in physics, biomedical research, and computer science, we have constructed networks of collaboration between scientists in each of these disciplines. In these networks two scientists are considered connected if they have coauthored one or...
Persistent link: https://www.econbiz.de/10005623663