RESUMO
The application of control strategies is increasingly used in wastewater treatment plants with the aim of improving effluent quality and reducing operating costs. Due to concerns about the progressive growth of greenhouse gas emissions (GHG), these are also currently being evaluated in wastewater treatment plants. The present article proposes a fuzzy controller for plant-wide control of the biological wastewater treatment process. Its design is based on 14 inputs and 6 outputs in order to reduce GHG emissions, nutrient concentration in the effluent and operational costs. The article explains and shows the effect of each one of the inputs and outputs of the fuzzy controller, as well as the relationship between them. Benchmark Simulation Model no 2 Gas is used for testing the proposed control strategy. The results of simulation results show that the fuzzy controller is able to reduce GHG emissions while improving, at the same time, the common criteria of effluent quality and operational costs.
RESUMO
PURPOSE: The purpose of the study is to explain the cause-effect relationship in three patients who reported combined ruptures of the Achilles tendon and the gastrosoleus complex 6 months after they had received corticosteroids injections for the management of retrocalcaneal bursitis. METHODS: Three cryopreserved cadavers (three men, three left legs) were examined to assess the anatomic connection between the retrocalcaneal bursa and the Achilles tendon (distal and anterior fibers). Blue triptan medium contrast was injected. RESULTS: An unexpected connection between the retrocalcaneal bursa and the anterior fibers of the Achilles tendon was found in all instances. CONCLUSIONS: Local corticosteroid injection of the retrocalcaneal bursa may help the symptoms of retrocalcanear bursitis, but pose a risk of Achilles tendon rupture. This risk-benefit has to be taken into account when corticosteroid injections are prescribed to professional and high-level athletes.