Search results for "Simulation"

The assessment of volcanic gas hazard by means of numerical models: An example from Vulcano Island (Sicily)

1999

Volcanic activity can inject large quantities of gases and aerosols into the atmosphere both during and between eruptions, creating a health risk for the local population. The paper describes how the volcanic gas concentration in the air can be computed by a flow model simulating the wind field over a digital terrain model of the volcano coupled with a Lagrangian particle model that uses the known (measured) gas emission rates to simulate gas dispersion. The coupling provides hazard maps for a number of meteorological conditions, introduced as boundary and initial conditions to the wind flow model, and permits the estimation of the risk both for actual and increased emission rates. An appli…

Geometric Brownian Motion (GBM) of Stock Indexes and Financial Market Uncertainty in the Context of Non-Crisis and Financial Crisis Scenarios

2022

The present article proposes a methodology for modeling the evolution of stock market indexes for 2020 using geometric Brownian motion (GBM), but in which drift and diffusion are determined considering two states of economic conjunctures (states of the economy), i.e., non-crisis and financial crisis. Based on this approach, we have found that the GBM proved to be a suitable model for making forecasts of stock market index values, as it describes quite well their future evolution. However, the model proposed by us, modified geometric Brownian motion (mGBM), brings some contributions that better describe the future evolution of stock indexes. Evidence in this regard was provided by analyzing …

Directionlets: Anisotropic Multidirectional representation with separable filtering

2006

In spite of the success of the standard wavelet transform (WT) in image processing in recent years, the efficiency of its representation is limited by the spatial isotropy of its basis functions built in the horizontal and vertical directions. One-dimensional (1-D) discontinuities in images (edges and contours) that are very important elements in visual perception, intersect too many wavelet basis functions and lead to a nonsparse representation. To efficiently capture these anisotropic geometrical structures characterized by many more than the horizontal and vertical directions, a more complex multidirectional (M-DIR) and anisotropic transform is required. We present a new lattice-based pe…

Larval fish assemblages in the central Mediterranean Sea: spatio spatio-temporal dynamics and biological effect on early life stage of Sardinella aur…

Cachez ce site que je ne saurais voir ! - La dissimulation des sites sensibles dans les outils interactifs de géovisualisation

2013

Interactive geovisualization portals, set up on the Internet after the iconic Google Maps, are highly regarded by the public. They provide the ability to see from above the surface of our planet, and more specifically the French territory in the case of Geoportail. But like Icare, swept away by the flyby, we almost forget the prohibition of approaching too close certain objects. On French territory, some 150 sites are in fact hidden by the IGN. This paper question the relevance and efficiency of this operation imposed on the main body of production and dissemination of spatial information in France.

HSV-1 Glycoprotein D and Its Surface Receptors: Evaluation of Protein–Protein Interaction and Targeting by Triazole-Based Compounds through In Silico…

2023

Protein–protein interactions (PPI) represent attractive targets for drug design. Thus, aiming at a deeper insight into the HSV-1 envelope glycoprotein D (gD), protein–protein docking and dynamic simulations of gD-HVEM and gD-Nectin-1 complexes were performed. The most stable complexes and the pivotal key residues useful for gD to anchor human receptors were identified and used as starting points for a structure-based virtual screening on a library of both synthetic and designed 1,2,3-triazole-based compounds. Their binding properties versus gD interface with HVEM and Nectin-1 along with their structure-activity relationships (SARs) were evaluated. Four [1,2,3]triazolo[4,5-b]pyridines were i…

Up-wind difference approximation and singularity formation for a slow erosion model

2020

We consider a model for a granular flow in the slow erosion limit introduced in [31]. We propose an up-wind numerical scheme for this problem and show that the approximate solutions generated by the scheme converge to the unique entropy solution. Numerical examples are also presented showing the reliability of the scheme. We study also the finite time singularity formation for the model with the singularity tracking method, and we characterize the singularities as shocks in the solution.

Comparison Between Conventional and Vegetated Roof by Means of a Dynamic Simulation

2015

In this paper, a dynamic simulation of a building located in the Campus University of Palermo, Italy, has been carried out. We considered two different scenarios; in the first one, the building as it is, with a conventional covering, while in the second one the roof was equipped with a green roof. The results of the two simulations have been compared, suggesting that such building component could contribute to the energy savings of the building. However, it has to be considered as part of other possible actions devoted to improve the energy efficiency of the whole building. (C) 2015 The Authors. Published by Elsevier Ltd. This is an open access article under the CC-BY-NC-ND license (http://…

The Application of the Life-Cycle Assessment in the Building Sector: An Italian Case Study

2017

The building sector is one of the most relevant in terms of generation of wealth and occupation, but it is also responsible for significant consumption of natural resources and the generation of environmental impacts, mainly greenhouse gas emissions. In order to improve the eco profile of buildings during their life-cycle, the reduction of the use of resources and the minimization of environmental impacts have become, in the last years, some of the main objectives to achieve in the design of sustainable buildings. The application of the life-cycle thinking approach, looking at the whole life cycle of buildings, is of paramount importance for a real decarbonization and reduction of the envir…

Ventilative cooling application in Mediterranean buildings: impacts on grid interaction and load match

2016

The concept of load matching refers to the simultaneous occurrence of loads and generation in buildings: it can be increased and optimised with modifications on both the energy demand and generation, but its pre-requisite is to guarantee passive energy efficiency. In the Mediterranean areas, a major challenge in new buildings is the increasing overheating even during mildly hot seasons. Ventilative cooling can be a potential solution to such issues and have an impact on load match in buildings and their grid interaction. The study analyses the potential of ventilative cooling to improve the load match in three different case studies in Italy. Ventilative cooling proved viable in moderately …