modelling

Wavelet-based Heat Kernel Derivatives: Towards Informative Localized Shape Analysis

In this paper, we propose a new construction for the Mexican hat wavelets on shapes with applications to partial shape matching. Our approach takes its main inspiration from the well-established methodology of diffusion wavelets. This novel construction allows us to rapidly compute a multi-scale family of Mexican hat wavelet functions, by approximating the derivative of the heat kernel. We demonstrate that this leads to a family of functions that inherit many attractive properties of the heat kernel (e.g.

A mathematical, experimental study on iron rings formation in porous stones

In this interdisciplinary paper, we study the formation of iron precipitates – the so-called Liesegang rings – in Lecce stones in contact with iron source. These phenomena are responsible of exterior damages of lapideous artifacts, but also in the weakening of their structure. They originate in presence of water, determining the flow of carbonate compounds mixing with the iron ions and then, after a sequence of reactions and precipitation, leading to the formation of Liesegang rings.

Treatment planning in microwave thermal ablation: clinical gaps and recent research advances

Microwave Thermal Ablation (MTA) is a minimally invasive therapeutic technique aimed at destroying pathologic tissues through a very high temperature increase induced by the absorption of an electromagnetic field at microwave (MW) frequencies. Open problems, which are delaying MTA applications in clinical practice, are mainly linked to the extremely high temperatures, up to 120 °C, reached by the tissue close to the antenna applicator, as well as to the ability of foreseeing and controlling the shape and dimension of the thermally ablated area.

Evolution of physicochemical properties of pear during drying by conventional techniques, portable-NMR, and modelling

The knowledge of changes in the properties of foods that occur with processing is needed for designing better drying methods that preserve desirable characteristics and minimize/eliminate undesirable ones. To this aim, this study analysed the effect of convective drying at 45–55 °C on physicochemical properties of pear. The drying kinetics, shrinkage and SEM images were evaluated. Portable-NMR was used to determine the drying moisture profile of pears and thickness reduction.

Advances in electric resistivity tomography. Theory and case studies

In this work, we aim to investigate the advances in ERT investigation made during the last years for near-surface applications, discussing the role played by the main parameters on data acquisition, forward modeling, and inversion and presenting strategies for removing the ambiguities arising in interpretation of geoelectric models. In Section 2.1, electric theory was briefly introduced considering electrodes both as point sources (commonly used approximation for ERT modeling) and as finite-length objects.

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