2 resultados para Solos - Poluição

em Universidade Federal de Uberlândia


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The transport of people and goods contributes to the deterioration of the environment in urban areas because of the generation of pollution, such as, air, noise, soil, water or visual degradation. The heavy vehicles that use diesel as fuel are mainly responsible for the emission of nitrogen oxides (NOx) and particulate matter (PM), contributing to participation of the transport sector in air pollution. In addition, there is emission of Greenhouse Gas (GHG) whose main component is carbon dioxide (CO2). In most major cities, public transportation is often considered as a less polluting alternative compared to the private vehicle, in view of the potential to reduce, per passenger, the emissions of GHG and air pollutants. The study area was the city of Uberlândia and the objects of study were the trunk lines of the Sistema Integrado de Transporte (SIT). The emissions of NOx, PM and CO2 were estimated through the bottom-up approach which used the route of each bus line and also fuel consumption obtained through simulation from the TSIS software. The software has some result limitations, there are no report about the emission of pollutants by bus, and it is not able to change specifications for the fuel used by the fleet. The results obtained through calculations of pollutants and GHG emission by the bottom-up approach show that the emission is higher when using fuel comsuption obtained in simulation than using distance. For the results considering fuel and distance there was a reduction in emissions comparing ethanol and diesel.

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This work's objective is the development of a methodology to represent an unknown soil through a stratified horizontal multilayer soil model, from which the engineer may carry out eletrical grounding projects with high precision. The methodology uses the experimental electrical apparent resistivity curve, obtained through measurements on the ground, using a 4-wire earth ground resistance tester kit, along with calculations involving the measured resistance. This curve is then compared with the theoretical electrical apparent resistivity curve, obtained through calculations over a horizontally strati ed soil, whose parameters are conjectured. This soil model parameters, such as the number of layers, in addition to the resistivity and the thickness of each layer, are optimized by Differential Evolution method, with enhanced performance through parallel computing, in order to both apparent resistivity curves get close enough, and it is possible to represent the unknown soil through the multilayer horizontal soil model fitted with optimized parameters. In order to assist the Differential Evolution method, in case of a stagnation during an arbitrary amount of generations, an optimization process unstuck methodology is proposed, to expand the search space and test new combinations, allowing the algorithm to nd a better solution and/or leave the local minima. It is further proposed an error improvement methodology, in order to smooth the error peaks between the apparent resistivity curves, by giving opportunities for other more uniform solutions to excel, in order to improve the whole algorithm precision, minimizing the maximum error. Methodologies to verify the polynomial approximation of the soil characteristic function and the theoretical apparent resistivity calculations are also proposed by including middle points among the approximated ones in the verification. Finally, a statistical evaluation prodecure is presented, in order to enable the classication of soil samples. The soil stratification methodology is used in a control group, formed by horizontally stratified soils. By using statistical inference, one may calculate the amount of soils that, within an error margin, does not follow the horizontal multilayer model.