Luísa Vieira Lucchese

University of Pittsburgh | Pitt · Geology and Environmental Science

It is well-known that deposits of turbidity currents can significantly change bathymetry. The deposit of a current can alter sedimentation that happens afterwards, changing the deposit shape of a turbidity current. Direct Numerical Simulations of tridisperse turbidity currents are performed considering a rectangular channel and finite-release initi...

Landslide susceptibility maps can be developed with artificial neural networks (ANNs). In order to train our ANNs, a digital elevation model (DEM) and a scar map of one previous event were used. Eleven attributes are generated, possibly containing redundant information. Our base model is formed by, essentially, one input (the DEM), eleven attribute...

Landslide susceptibility assessment using Artificial Neural Networks (ANNs) requires occurrence (landslide) and nonoccurrence (not prone to landslide) samples for ANN training. We present empirical evidence that a priori intervention on the nonoccurrence samples can produce models that are improper for generalization. Thirteen nonoccurrence cases b...

Two Artificial Intelligence (AI) methods, Fuzzy Inference System (FIS) and Artificial Neural Network (ANN), are applied to Landslide Susceptibility Mapping (LSM), to compare complementary aspects of the potentials of the two methods and to extract physical relationships from data. An index is proposed in order to rank and filter the FIS rules, sele...

In this paper, an original methodology for landslide susceptibility mapping (LSM) is presented. It consists of bagging ensembles of artificial neural networks (ANNs) and random forests (RFs), and hybrid bagging ensembles of these models. It is applied on the area of the Itajaí-Açu river valley. In December 2020, there was an extreme rainfall in the...

Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder characterized by deficits in communication and social interaction, and presence of repetitive behaviors, and restricted interests. Many structural and functional brain alterations can be observed in individuals with ASD. Therefore, functional magnetic resonance imaging (fMRI) has been...

Background Deep learning models, particularly convolutional neural networks (CNNs), have shown promise in Alzheimer’s disease (AD) classification using tau PET data. However, limited sample sizes and unharmonized tau tracers present challenges to developing an agnostic tau tracer tool to predict AD using machine learning. Transfer learning, which l...

Full-text: https://anais.abrhidro.org.br/job.php?Job=13075 Em 17 de dezembro de 2020, um evento extremo de precipitação desencadeou deslizamentos de terra na zona limítrofe dos municípios de Presidente Getúlio, Ibirama e Rio do Sul, no estado de Santa Catarina, Brasil. O Serviço Geológico do Brasil (CPRM) havia divulgado, em seu portal, uma carta...

Shallow water models are commonly used to simulate dam-break flow; however, shallow water equations usually assume a hydrostatic pressure assumption that can limit model applications. Dam-break flow can also be solved by total pressure formulation with Navier-Stokes equations, that are computationally more expensive but can deal with a wider range...

Gravity currents are gravitational fluxes triggered by density difference between two fluids. A sub-classification of those are turbidity currents, in which the denser fluid is composed by the lighter fluid plus suspended particles. Many papers had shown turbidity currents dynamics, although none of the papers found had applied changes in the simul...

Turbidity currents are gravitational flows triggered by density difference between two fluids, in which the heavier one has suspended particles. Many authors showed turbidity currents dynamics, although none of them applied topography changes due to deposit during their own simulation. Hoffmann et al. (2015) simulated successive turbidity currents,...

Poster presented at EPTT 2016 (10th ABCM School on Transition and Turbulence), sept. 2016.

This paper aims to study a gravity current interacting with a fixed or oscillating cylinder, via 2D numerical simulation. The oscillating cylinder is sumbmited to vortex induced vibration (VIV) in the vertical direction, characterizing one degree of freedom. The cylinder axis is parallel to the channel bottom and transverse to the gravity current....

Rectangular sedimentation basins are used on drinking water treatment in the stage of water clarification. When used, they tend to be the major part of the water treatment facility. In order to analyze the turbulent instabilities that can occur, a Direct Numerical Simulation was performed. The Incompact3d code has been used to implement the boundar...

Tanques de decantação retangulares fazem parte da etapa de clarificação em um tratamento de água convencional completo. Como são as instalações que tendem a ocupar mais espaço na planta das Estações de Tratamento de Água (ETAs), buscou-se simulá-las, com vistas a analisar as proporções geométricas destes tanques, além de observar a ação da turbulên...

Translation of INCOMPACT3D USER GUIDE version 2.0/Sylvain Laizet

Submarine conduits can be considered as obstacles for a gravity current that propagates under the sea. It is desirable to know how these natural currents behave in this subaquatic interaction, and how the conduit responds to it (the strain it handles). This work is about the interaction of a gravity current propagating in a channel with an obstacle...