Made available in DSpace on 2015-04-14T13:56:35Z (GMT). No. of bitstreams: 1 465061.pdf: 182147 bytes, checksum: f7a4815079fd1da1390d1f0d759a33b8 (MD5) Previous issue date: 2014-11-03 / This dissertation presents the development and evaluation of a prototype for the stimulus of the olfactory system, which will be employed in the study of neuroimages gathered by functional magnetic resonance image (fRMI). Basic requirements for the prototype include: safety, human physiology and environmental compatibility, homogeneous release of aerosolized stimuli, accurate control of pressure and flow conditions, support for up to three distinct substances, and substance mixing capability. Digital image processing techniques were used in evaluation process through the usage of Matlab in order to better assess the reliability and reproducibility in the evaluation of the of the samples released under controlled constant pressure of 3.5+/- 0.3 kgf/cm?, different flows (4 l/min, 6 l/min, 8 l/min and 10 l/min), and different duration periods (10s, 15s, 20s, 30s, 60s and 90s). Charts with the image profiles, histograms and statistical data were generated and analyzed. The delay in the system, important information for any study in fRMI, was measured using an oxygen sensor and custom software solution. Experiments for the determination of the amount of substance required and the real capability of mixing substances were performed with parameters based on the results from the digital image processing analysis. / Esta disserta??o de mestrado apresenta o desenvolvimento e a avalia??o de um prot?tipo para estimular o sistema olfativo, o qual ser? empregado em estudos de neuroimagens obtidas pela modalidade de resson?ncia magn?tica funcional. Para o desenvolvimento do prot?tipo foram definidos requisitos b?sicos que o sistema deveria possuir: seguran?a, compatibilidade com o ambiente e com as caracter?sticas fisiol?gicas humanas, dispensar amostra aerossolizada, precis?o para controlar e regular vaz?o e press?o, capacidade para tr?s subst?ncias distintas e possibilidade de mistur?-las. A avalia??o utilizou t?cnicas de processamento de imagens digitais com a utiliza??o do software Matlab com a finalidade de estudar a confiabilidade e reprodutibilidade na quantifica??o da amostra dispensada utilizando press?o fixa de 3,5 +/- 0,3 kgf/cm? e as vari?veis fluxo (4 l/min, 6 l/min, 8 l/min e 10 l/min) e tempo (10s, 15s, 20s, 30s, 60s e 90s). Os resultados foram analisados atrav?s de gr?ficos de perfil dos pixels, histogramas e dados estat?sticos das imagens. O atraso do sistema, dado fundamental para pesquisas em resson?ncia magn?tica funcional, foi medido com a utiliza??o de um sensor de oxig?nio e um software desenvolvido em LabVIEW. Experimentos para medir o consumo e a possibilidade de misturar as amostras foram realizados utilizando os resultados obtidos com a valida??o por processamento de imagens digitais.