Search results for " modelling."

Analysis of Spatially and Temporally Overlapping Events with Application to Image Sequences

2006

Counting spatially and temporally overlapping events in image sequences and estimating their shape-size and duration features are important issues in some applications. We propose a stochastic model, a particular case of the nonisotropic 3D Boolean model, for performing this analysis: the temporal Boolean model. Some probabilistic properties are derived and a methodology for parameter estimation from time-lapse image sequences is proposed using an explicit treatment of the temporal dimension. We estimate the mean number of germs per unit area and time, the mean grain size and the duration distribution. A wide simulation study in order to assess the proposed estimators showed promising resul…

A Grain Boundary Formulation for the Analysis of Three-Dimensional Polycrystalline Microstructures

2013

A 3D grain boundary formulation is presented for the analysis of polycrystalline microstructures. The formulation is expressed in terms of intergranular displacements and tractions, that play an important role in polycrystalline micromechanics, micro-damage and micro-cracking. The artificial morphology is generated by Hardcore Voronoi tessellation, which embodies the main statistical features of polycrystalline microstructures. Each crystal is modeled as an anisotropic elastic region and the integrity of the aggregate is restored by enforcing interface continuity and equilibrium between contiguous grains. The developed technique has been applied to the numerical homogenization of cubic poly…

Coupled VEM–BEM Approach for Isotropic Damage Modelling in Composite Materials

2023

Numerical prediction of composite damage behaviour at the microscopic level is still a challenging engineering issue for the analysis and design of modern materials. In this work, we document the application of a recently developed numerical technique based on the coupling between the virtual element method (VEM) and the boundary element method (BEM) within the framework of continuum damage mechanics (CDM) to model the in-plane damage evolution characteristics of composite materials. BEM is a widely adopted and efficient numerical technique that reduces the problem dimensionality due to its underlying formulation. It substantially simplifies the pre-processing stage and decreases the compu…

Tsunami Vulnerability Evaluation for a Small Ancient Village on Eastern Sicily Coast

2022

The Ionian sea is prone to tsunamis due to its proximity to the Calabrian subduction zone, which is one of the major tsunamigenic areas of the Mediterranean. The tsunami disaster risk is, nowadays, significantly higher due to the increased exposure of buildings as a result of the economic and touristic growth of the Mediterranean coastal areas. This study focuses on Marzamemi, a small village in the western coast of Sicily, since its morphology and human presence amplify the need to assess its buildings’ vulnerability. The main objective of this research is to quantify the building vulnerability to tsunami hazards using a physical and realistic tsunami scenario. For this purpose, the relati…

A method of data structuring for the study of diffusion processes of raw materials and manufactured objects

2017

International audience; Workgroup 3 of the ArchaeDyn II programme aims at studying the diffusion systems of products in ancient times. In order to be able to structure data in GIS in an appropriate way, we propose to go through three levels of modelling: the first one aims at gathering together the different components of the diffusion systems taking into account their interactions; the second corresponds to a conceptual data model created with the help of the HBDS method, that will, as we get to the third stage, lead to the creation of a "three-dimensional" geodatabase. Here we point out the fact that the approach through the simple notion of “site” is not sufficient to study the products’…

Business Modelling. Languages and Tools

2004

The paper provides an overview of business modelling techniques — both at language and tool level. The basic elements of some most popular business modelling languages are briefly outlined, including the GRAPES-BM language developed by IMCS, University of Latvia. The paper presents also the basic principles, how metamodel based generic modelling techniques can be used for supporting several modelling notations simultaneously.

Urban 3-D models for plannig of mobile telephony systems

2000

This paper deals with an application of numerical cartography, carried out by means of digital photogrammetry techniques, aimed at the planning of mobile telephony cells. Particularly, urban 3-D vector models (wireframe), got by digital restitution and integrated by raster images referred to rectified buildings facades, were carried out in a sample area selected inside the Orleans Park, seat of the Palermo University. Then such models were processed by computer graphics techniques owing to the operations of rendering and animation. These 3-D representations could come in very useful for study and planning of mobile telephony networks in urban areas.

A Definitive Pharmacophore Modelling Study on CDK2 ATP Pocket Binders: Tracing the Path of New Virtual High-Throughput Screenings

2020

Cyclin Dependent Kinases-2 (CDK2) are members of serine/threonine protein kinases family. They play an important role in the regulation events of the eukaryotic cell division cycle, especially during the G1 to S phase transition. Experimental evidence indicate that excessive expression of CDK2s should cause abnormal cell cycle regulation. Therefore, since a long time, CDK2s have been considered potential therapeutic targets for cancer therapy. In this work, onehundred and forty-nine complexes of inhibitors bound in the CDK2-ATP pocket were submitted to short MD simulations (10ns) and free energy calculation. Comparison with experimental data (K<sub>i</sub>, K<sub>d</su…

CFD simulation of solid-liquid suspension startup in a stirred tank

2008

Evaluating several satellite precipitation estimates and global ground-based dataset on Sicily (Italy)

2012

The developing of satellite-based precipitation retrieval systems, presents great potentialities for several ap­ plications ranging from weather and meteorological applications to hydrological modelling. Evaluating perfor­ mances for these estimates is essential in order to understand their real capabilities and suitability related to each application. In this study an evaluation analysis of satellite precipitation retrieval systems has been carried out for the area of Sicily (Italy). Sicily is an island in the Mediterranean sea with a particular climatology and morphology, which is considered as an interesting test site for satellite precipitation products on the European mid-latitude area…