Determinação do melhor substrato e temperatura para germinação de sementes de araçá (Psidium cattleianum).

Resumo

Adaptive linearizing control of bioreactors

In this communication we shall present developments concerning the synthesis of Single-Input, Single-Output (SISO) and Multi-Input, Multi-Output (MIMO) adaptive linearizing algorithms for the operation of bioreactors. Results will be illustrated for the baker’s yeast fermentation process. The synthesis of these non-linear control laws is performed by employing differential geometry techniques with system linearization by state feedback. The controller design includes a step of order reduction of the process state model. The adaptive feature comes from the on-line estimation of the required process time varying parameters. The adaptive algorithm proposed enforces a desired and pre-set second order convergence dynamics as originally introduced by Oliveira et al. (1). Formulating the estimator on this basis leaves the user with the choice of two simple and intuitive tuning parameters with physical meaning - a damping coefficient and a natural period of oscillation.Instituto de Sistemas e Robótica; Universidade do Porto. Faculdade de Engenharia; Comunidade Europeia, programa HC&M

A new adaptive scheme for the adaptive linearizing control of bioprocesses

This work deals with the development of model-based adaptive control algorithms for bioprocess operation. Non-linear adaptive control laws are proposed for single input single output regulation. Parameters are continuously adapted following a new adaptive scheme which ensures second-order dynamics of the parameter error system. A computational study is presented of the application of this theory to baker’s yeast fermentation. Results put in evidence the efficient performance both of the adaptive scheme and of the related control laws.Instituto de Sistemas e Robótica, Pólo do Porto

Eficiência de herbicidas no controle de gramíneas em seringueira.

Em Rondônia, capim-amargoso (Digitaria insularis (L.) Mez ex Ekman), capim-colchão (Digitaria horizontalis Willd.), capim-milhã (Digitaria ciliaris (Retz.) Koel), capim pé-de-galinha (Eleusine indica, (L.) Gaertn) e capim rabo-de-burro (Andropogon bicornis L.), são ervas daninhas muito freqüentes em cultivos de seringueira, o que justifica a realização de trabalhos específicos para seu controle. O objetivo deste trabalho foi avaliar e comparar nas condições de campo, a eficácia de três herbicidas pós-emergentes no controle de gramíneas importantes em cultivo de seringueira em Rondônia.bitstream/item/77101/1/FOL-7728-0001.pd