The Experts below are selected from a list of 21 Experts worldwide ranked by ideXlab platform
Fábio Celestino Pereira - One of the best experts on this subject based on the ideXlab platform.
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Análise de desempenho de algoritmos para auxílio ao reconhecimento de fissuras em fachadas com revestimento de argamassa visando sua embarcação em VANTs
Universidade Federal do Rio Grande do Sul, 2015Co-Authors: Fábio Celestino PereiraAbstract:A utilização de Veículos Aéreos Não Tripulados (VANTs), também chamados UAV (Unmanned Aerial Vehicle) vem ganhando espaço nas mais diversas áreas, tais como inspeções em linhas de transmissão e em torres de fracionamento de refinarias, entre outros. Já na construção civil, estudos recentes estão sendo focados na utilização dos VANTs para inspeção de pontes, viadutos e estradas. O presente trabalho visa fornecer uma análise para o uso de VANT na área civil, na detecção de manifestações patológicas em revestimentos de argamassa, de forma a auxiliar na procura por fissuras em fachadas, sobretudo aqueles que a visualização esteja prejudicada, seja pela distância ou pela acessibilidade difícil ao local. Este trabalho analisa possíveis implementações de dois algoritmos de processamentos de imagens desenvolvidos a partir da ferramenta MATLAB para a indicação de presença de fissuras na alvenaria, obtendo o desempenho destes diferentes algoritmos quando executados em software em plataforma que possibilite a embarcação em VANTs. Utilizando a geração automática de código em C a partir do ambiente MATLAB, é realizada uma análise temporal em plataforma ARM e RISC dos algoritmos propostos, demonstrando a oportunidade de utilização de dispositivos na tarefa de processamento de imagem para a aplicação proposta. Esta análise possibilita a previsão do comportamento na utilização de um VANT, uma vez que isto pode impactar na velocidade durante a aplicação e consequentemente sua autonomia.The use of Unmanned Aerial Vehicles (UAVs), has been gaining space in several areas, such as inspections of transmission lines, refineries Fractionation Towers among others. In the construction, recent studies have been focused on the use of UAVs for inspection of bridges, viaducts and roads. The present study aims to provide an analysis using UAVs in the civil construction area, in the detection of pathologic manifestations mortar coatings in order to aid in the search for cracks in the facades especially those that visualization is impaired, or may be the distance the accessibility difficult to spot. This paper provides an analysis of two algorithms of image processing developed from the Matlab tool for indicating the presence of cracks in masonry, getting the performance of these different algorithms when implemented in software platform that enables the vessel in UAV. Using the automatic generation of C/C++ code from the MATLAB environment is performed the temporal analysis on ARM and RISC plataform of the proposed algorithms demonstrates the opportunity to use devices in the image processing task for the proposed application. This analysis allows the prediction of the behavior of a UAV using one since it can impact velocity during application, and therefore their autonomy
Tamer S. Ahmed - One of the best experts on this subject based on the ideXlab platform.
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Optimization of a saturated gas plant: Meticulous simulation-based optimization - A case study.
Journal of Advanced Research, 2020Co-Authors: Salah H. Bayoumy, Sahar El-marsafy, Tamer S. AhmedAbstract:Abstract An optimization-simulation strategy has been applied by coupling a commercial process simulator (Aspen HYSYS®) with a programming tool (MATLAB®) to produce a precise steady state simulation-based optimization of a whole green-field saturated gas plant as a real case study. The plant has more than 100-components and comprises interacting three-phase Fractionation Towers, pumps, compressors and exchangers. The literature predominantly uses this coupling to optimize individual units at small scales, while paying more attention to optimizing discrete design decisions. However, bridging the gap to scalable continuous design variables is indispensable for industry. The strategy adopted is a merge between sensitivity analysis and constrained bounding of the variables along with stochastic optimization algorithms from MATLAB® such as genetic algorithm (GA) and particle swarm optimization (PSO) techniques. The benefits and shortcomings of each optimization technique have been investigated in terms of defined inputs, performance, and finally the elapsed time for such highly complex case study. Although, both GA and PSO were satisfactory for the optimization, the GA provided greater confidence in optimization with wider ranges of constrained bounds. The implemented strategy precisely reached the best operating conditions, within the range covered, by minimizing the total annual cost while maintaining at least 92% butane recovery as a process guarantee for the whole plant. The optimization-simulation strategy applied in the current work is recommended to be used in brownfields to optimize the operating conditions since they are susceptible to continuous changes in feedstock conditions.
P.m Rahimi - One of the best experts on this subject based on the ideXlab platform.
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A microscopic approach to determine the origin and mechanism of coke formation in Fractionation Towers
Fuel, 2003Co-Authors: T Gentzis, P.m RahimiAbstract:Abstract This study investigated the deposition of coke in a Fractionation tower following thermal cracking of heavy feedstocks. A simple microscopic technique was used to determine whether the coke formed in situ in the fractionator or was formed elsewhere (e.g. in the reactor vessel) and was subsequently entrained in the vapour phase. The reflectance of coke types, mode of occurrence, and distributions from the bottom to the top of the fractionator were used to interpret the range of temperatures responsible for coke formation. Both isotropic and anisotropic (mosaic) coke was observed in the samples. The anisotropic textural features indicated that asphaltenes carry-over was a minor problem and that the vast majority of the isotropic coke precursors were the maltenes present in the gas phase that entered the fractionator. The formation of perfectly spherical mesophase was attributed to the gas oil stream itself used to quench the vapours exiting the thermal cracking vessel. Microscopic evidence, along with metals concentration in the coke at various locations of the operation provided useful information as to the nature of the coke precursors.
Salah H. Bayoumy - One of the best experts on this subject based on the ideXlab platform.
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Optimization of a saturated gas plant: Meticulous simulation-based optimization - A case study.
Journal of Advanced Research, 2020Co-Authors: Salah H. Bayoumy, Sahar El-marsafy, Tamer S. AhmedAbstract:Abstract An optimization-simulation strategy has been applied by coupling a commercial process simulator (Aspen HYSYS®) with a programming tool (MATLAB®) to produce a precise steady state simulation-based optimization of a whole green-field saturated gas plant as a real case study. The plant has more than 100-components and comprises interacting three-phase Fractionation Towers, pumps, compressors and exchangers. The literature predominantly uses this coupling to optimize individual units at small scales, while paying more attention to optimizing discrete design decisions. However, bridging the gap to scalable continuous design variables is indispensable for industry. The strategy adopted is a merge between sensitivity analysis and constrained bounding of the variables along with stochastic optimization algorithms from MATLAB® such as genetic algorithm (GA) and particle swarm optimization (PSO) techniques. The benefits and shortcomings of each optimization technique have been investigated in terms of defined inputs, performance, and finally the elapsed time for such highly complex case study. Although, both GA and PSO were satisfactory for the optimization, the GA provided greater confidence in optimization with wider ranges of constrained bounds. The implemented strategy precisely reached the best operating conditions, within the range covered, by minimizing the total annual cost while maintaining at least 92% butane recovery as a process guarantee for the whole plant. The optimization-simulation strategy applied in the current work is recommended to be used in brownfields to optimize the operating conditions since they are susceptible to continuous changes in feedstock conditions.
T Gentzis - One of the best experts on this subject based on the ideXlab platform.
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A microscopic approach to determine the origin and mechanism of coke formation in Fractionation Towers
Fuel, 2003Co-Authors: T Gentzis, P.m RahimiAbstract:Abstract This study investigated the deposition of coke in a Fractionation tower following thermal cracking of heavy feedstocks. A simple microscopic technique was used to determine whether the coke formed in situ in the fractionator or was formed elsewhere (e.g. in the reactor vessel) and was subsequently entrained in the vapour phase. The reflectance of coke types, mode of occurrence, and distributions from the bottom to the top of the fractionator were used to interpret the range of temperatures responsible for coke formation. Both isotropic and anisotropic (mosaic) coke was observed in the samples. The anisotropic textural features indicated that asphaltenes carry-over was a minor problem and that the vast majority of the isotropic coke precursors were the maltenes present in the gas phase that entered the fractionator. The formation of perfectly spherical mesophase was attributed to the gas oil stream itself used to quench the vapours exiting the thermal cracking vessel. Microscopic evidence, along with metals concentration in the coke at various locations of the operation provided useful information as to the nature of the coke precursors.
