Particle Simulations
Mostrando 1-12 de 103 artigos, teses e dissertações.
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1. Discrete element modeling of non-spherical particles using a spherical shape
Abstract Real non-spherical particles can be modeled using the Discrete Element Method (DEM) with sphere clusters, superquadrics, or polyhedral particles. However, in applications involving a considerable number of particles, the analysis can become impracticable. The goal of this study is to demonstrate how well spherical particles can reproduce the flow of
REM, Int. Eng. J.. Publicado em: 2020-09
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2. Compatibility of GROMOS-Derived Atomic Parameters for Lipopolysaccharide Membranes with the SPC/E Water Model and Alternative Long-Range Electrostatic Treatments Using Single Nonbonded Cutoff and Atom-Based Charge Schemes
Recent developments of GROMACS v.2016 ceased to support methodological approaches used in the development and validation of the GROMOS force field. We investigated the performance of a previously developed extension of the GROMOS force field for lipopolysaccharides to reproduce the structural dynamics of bacterial outer membrane (OM) using a single cutoff fo
J. Braz. Chem. Soc.. Publicado em: 21/10/2019
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3. A Model Updating Method for Plate Elements Using Particle Swarm Optimization (PSO), Modeling the Boundary Flexibility, Including Uncertainties on Material and Dimensional Properties
Abstract It is a well-known fact that, in a real engineering situation, fixtures are not ideally stiff, so numerical simulations using them are unlikely to present results that are consistent with the experimental ones. The present paper intends to describe a model updating methodology inserting translational and rotational springs in order to better represe
Lat. Am. j. solids struct.. Publicado em: 22/10/2018
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4. Development of Synthetic Slag with Marble Waste and Calcium Aluminate Agents for Cast Iron Desulfurization
The aim of this work was to study the use of slags to desulfurize cast iron. It was proposed to use alumina instead of fluorspar. In addition, marble waste was used instead of lime. Simulations applying Thermo-Calc® software were carried out in order to obtain the theoretical phases using thermodynamic data. Then, a comparison between theoretical data and e
Mat. Res.. Publicado em: 13/07/2017
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5. Robust Optimal Adaptive Trajectory Tracking Control of Quadrotor Helicopter
Abstract This paper focuses on robust optimal adaptive control strategy to deal with tracking problem of a quadrotor unmanned aerial vehicle (UAV) in presence of parametric uncertainties, actuator amplitude constraints, and unknown time-varying external disturbances. First, Lyapunov-based indirect adaptive controller optimized by particle swarm optimization
Lat. Am. j. solids struct.. Publicado em: 2017-06
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6. Path Planning for Unmanned Underwater Vehicle in 3D Space with Obstacles Using Spline-Imperialist Competitive Algorithm and Optimal Interval Type-2 Fuzzy Logic Controller
Abstract In this research, generation of a short and smooth path in three-dimensional space with obstacles for guiding an Unmanned Underwater Vehicle (UUV) without collision is investigated. This is done by utilizing spline technique, in which the spline control points positions are determined by Imperialist Competitive Algorithm (ICA) in three-dimensional s
Lat. Am. j. solids struct.. Publicado em: 2016-06
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7. Ultrafast Dynamics of Au Nanopyramid Interfaces Prepared by Nanosphere Lithography: Effect of Substrate Chemical Composition
This work describes ultrafast spectroscopy studies of Au triangular pyramid particle arrays deposited over glass (termed Au/glass), and 190 nm indium tin oxide (ITO) film (termed Au/ITO/glass) prepared by nanosphere lithography. The linear absorption spectra of Au/glass and Au/ITO/glass exhibit surface plasmon resonances at 800 and 870 nm, respectively, in g
J. Braz. Chem. Soc.. Publicado em: 2016-02
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8. Rapid Generation of Particle Packs at High Packing Ratios for DEM Simulations of Granular Compacts
Abstract In this work we present a simple, fast technique for generating particle packs at high packing ratios aiming at the simulation of granular compacts via the discrete element method (DEM). We start from a random sequence addition particle generation algorithm to generate a "layer" of non-overlapping spherical particles that are let to evolve dynamical
Lat. Am. j. solids struct.. Publicado em: 2016-01
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9. Comparing OSNR based policies for an adaptive-alternative IA-RWA algorithm applied to all-optical networks
We propose two policies to select the route for an adaptive-alternative routing algorithm for all-optical networks. We use the NrPSR to find the Nr routes with lower cost for a given source-destination pair according to a cost function expanded in a power series (PSR) in which the coefficients are determined by a Particle Swarm Optimizer (PSO). The selected
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2013-12
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10. A comparative analysis of three metaheuristic methods applied to fuzzy cognitive maps learning
This work analyses the performance of three different population-based metaheuristic approaches applied to Fuzzy cognitive maps (FCM) learning in qualitative control of processes. Fuzzy cognitive maps permit to include the previous specialist knowledge in the control rule. Particularly, Particle Swarm Optimization (PSO), Genetic Algorithm (GA) and an Ant Col
Pesqui. Oper.. Publicado em: 08/11/2013
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11. Non-linear dynamics of a hanging rope
Two-dimensional motion of a hanging rope is considered. A multibody system with elastic-dissipative joints is used for modelling of the rope. The mathematical model based on the Lagrange formalism is presented. Results of some numerical simulations are shown for the mechanical system with kinematic excitation. Basic tools are used to qualify dynamics of the
Lat. Am. j. solids struct.. Publicado em: 2013-01
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12. Simulação tridimensional de uma coluna de bolhas cilíndrica : análise em sistema bifásico por técnica de velocimetria por imagem de partícula (PIV), shadow imaging e simulação / Three-dimensional simulation of a cylindrical bubble column : analysis in biphase system by technique of particle image velocimetry (PIV), shadow imaging and simulation
This research aims to evaluate the numerical results from Computational Fluid Dynamics (CFD) simulations and experimental results obtained using Particle Image Velocimetry (PIV) and Shadow Imaging in a bubble column of 1m height, diameter of 14,5cm with a gas distributor with 5 holes of 1 mm diameter each one. The system studied was water-air. The study was
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 16/07/2012