Search results for "Modelling"
showing 10 items of 1353 documents
Dynamic Portfolio Optimization with Stochastic Programming
2010
Simplified model to evaluate the fate of micropollutants in an integrated urban drainage system: sensitivity analysis
2016
The paper presents the sensitivity analysis of an integrated urban water quality system by means of the global sensitivity analysis (GSA). Specifically, an home-made integrated model developed in previous studies has been modified in order to include the micropollutant assessment (namely, sulfamethoxazole - SMX). The model takes into account also the interactions between the three components of the system: sewer system (SS), wastewater treatment plant (WWTP) and the receiving water body (RWB). The analysis has been applied to an experimental catchment nearby Palermo (Italy): the Nocella catchment. Five scenarios each characterized by different combinations of sub-systems (i.e., SS, WWTP and…
On vortex shape in unbaffled stirred vessels as measured by digital image analysis
2012
In this work, digital image analysis coupled with a suitable shadowgraphy-based technique is employed to investigate the shape of the free-surface vortex that forms in uncovered unbaffled tanks stirred by either a D=T/3 Lightnin A310 or a D=T/3 Rushton turbine. The technique is based on back-lighting the vessel and suitably averaging vortex images over time. Data obtained show that the two different impellers give rise to quite different vortex shapes. A novel 2-parameter model is proposed that successfully describes vortex shapes obtained with both impellers.
An alternative formulation of the boundary element method
1982
Abstract The paper suggests an alternative formulation of the Boundary Element Method, in which singular solutions generated by unit dislocations are required and moreover the stresses at the interior points of the body are directly computed from the boundary quantities, without passing through the displacements. Relationships between the singular solutions for unit dislocation and unit force are derived.
MODELLING THE DISPERSION PROPERTIES OF MASS LINEAR CHAINS: EXPERIMENTS AND SIMULATIONS
2009
We analyze and discuss the results of an experiment with the goal of revealing the phonon-like acoustic dispersion curve. The experimental apparatus consists of a sonometer and an electromagnetic driver connected to a signal generator in order to establish standing waves along a stretched metal string (a guitar string) upon which a set of beads (used normally for fishing) has been fixed. The oscillation amplitude is measured by means of a detector connected to an MBL interface. We detect the resonance frequencies as function of the wave-number and obtain the corresponding dispersion curve. The results show that deviations from linearity occur when the wavelength is comparable with the dista…
Validation of models for sprays
2016
We consider complex fluids consisting of a dispersed phase (solid particles or liquid droplets) immersed in a gas. A class of models describing the dynamics of such a kind of systems is given by a system of partial differential equations where a kinetic equation, describing the dispersed phase, is coupled to a fluid equation for the background gas. The coupling is given by the drag force exerted by the gas on the dispersed phase. Within this class, we shall analyse the case where the kinetic equation is a Vlasov-type equation and the fluid equation are of Stokes or Navier-Stokes type. We shall discuss the validation problem for this class of models, i.e. the derivation of the equations of t…
Modelización computacional cardiaca
2020
Resumen Las enfermedades cardiovasculares tienen en la actualidad un gran impacto social y economico y constituyen una de las principales causas de mortalidad y morbilidad. Los modelos computacionales personalizados del corazon estan demostrando ser utiles tanto para ayudar a comprender los mecanismos subyacentes a las patologias cardiacas como para optimizar su tratamiento prediciendo la respuesta del paciente. En este contexto, se ha puesto en marcha la Red Espanola de Investigacion en Modelizacion Computacional Cardiaca (V-Heart SN). El objetivo general de V-Heart SN es el desarrollo de un modelo computacional multifisico y multiescala integrado del corazon. Este objetivo general se abor…
Modelización computacional cardiaca
2020
[EN] Cardiovascular diseases currently have a major social and economic impact, constituting one of the leading causes of mortality and morbidity. Personalized computational models of the heart are demonstrating their usefulness both to help understand the mechanisms underlying cardiac disease, and to optimize their treatment and predict the patient's response. Within this framework, the Spanish Research Network for Cardiac Computational Modelling (VHeart-SN) has been launched. The general objective of the VHeart-SN network is the development of an integrated, modular and multiscale multiphysical computational model of the heart. This general objective is addressed through the following spe…
A stochastic model of mutant growth
1987
Modeling methods for studying post-translational and transcriptional modifying enzymes.
2012
Biological catalysis is a complex chemical process that involves not only electronic reorganization in the substrate but also the reorganization of the catalyst. This complexity is even larger in the case of post-transcriptional and post-translational modifications which may involve the interaction between two biomacromolecules. However, the development over the past decades of new computational methods and strategies is offering a detailed molecular picture of the catalytic event and a deep understanding of the mechanisms of chemical reactions in biological environments. Here we review the efforts made in the last years to model catalysis in post-transcriptional and post-translational proc…