This paper investigates the impact of geometric semantic crossover operators in a wide range of symbolic regression problems. First, it analyses the impact of using Manhattan and Euclidean distance geometric semantic crossovers in the learning process. Then, it proposes two strategies to numerically optimize the crossover mask based on mathematical properties of these operators, instead of simp...

In this paper, we investigate the usefulness of work and school absenteeism surveillance as an early warning system for influenza. In particular, time trends in daily absenteeism rates collected during the A(H1N1)2009 pandemic are compared with weekly incidence rates of influenza-like illness (ILI) obtained from the Belgian Sentinel General Practitioner (SGP) network. The results indicate a ris...

A major objective of the Atmospheric Radiation Measurement (ARM) Program is to test and improve parameterizations for cloud and radiative processes. A common strategy adopted for this purpose within the ARM science team is to utilize single-column models (SCMs) driven by appropriate boundary conditions derived from observations, so as to isolate the parameterizations themselves. In practice, ac...

The climatic importance of the microphysical and radiative properties of clouds, particularly cloud droplet effective radii (re), optical depths (τ), and albedos are widely recognized. For reliable application of satellite datasets in cloud process and single column models, it is important to have a reasonable estimate of the errors in the derived cloud properties. When properly used, ground-ba...

Mitigation of the multiple risks associated with disruptions and runaway electrons in tokamaks involves competing demands. Success requires that each risk be understood sufficiently appropriate compromises can made. Here focus is on interaction short timescale magnetic-perturbations structure ITER closest to plasma, blanket modules covered by separated beryllium tiles. The effect this tiled sur...

The particles in an elastic plate are permitted to move by a surface diffusion process subject to the constraint that the total free energy does not increase. The static equilibrium, the quasistatic linear stability, and the quasi-static nonlinear evolution of the surface are examined under different loading conditions: tensile/compressive or #exural. The equilibrium con"gurations are such that...

Fluctuations in the crack tip structure should result in the release of elastic waves that propagate both into the bulk as well as along the surface. Ramanathan and Fisher (1997), and Morrisey and Rice (1998) examined such wave interactions in a series of increasingly sophisticated models. The possibility that in-plane and out-of-plane perturbations could persist along the crack surface, result...