We propose a fault tolerance method for torus NoCs capable of increase the yield with minimal performance overhead. The proposed approach consists in detecting and diagnosing interconnect faults using BIST structures and activating alternative paths for the faulty links. Experimental results show that alternative fault-free paths are found by the dynamic routing for 95% of the diagnosed faults (stuck-at and pairwise shorts within a single link or between any two links).

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Submerged membrane bioreactors (sMBR's) are a promising technology for nitrogen removal in recirculating aquaculture systems (RAS's). However, there are still relatively few reports on the experimental application of this strategy. In this study, a laboratory-scale system, mimicking a RAS fitted with a sMBR, was designed and automated, and a simple dynamic sMBR model including biological and physical phenomena was validated. The system was analyzed based on measurements collected by a data logging structure involving a programmable logic controller (PLC), an industrial network protocol and a LabView application software. This study confirms the suitability of sMBR systems within aquaculture applications. The dynamic model has good predictive capabilities and could be used for the design of advanced control structures, such as model predictive control.

The recirculating aquaculture system (RAS) is a land-based water treatment technology, which allows for farming aquatic organisms, such as fish, by reusing the water in the production (often less than 5%). This technology is based on the use of filters, either mechanical or biological, and can, in principle, be used for any species grown in aquaculture. Due to the low recirculation rate, ammonia accumulates in the system and must be converted into nitrate using nitrification reactors. Although less toxic for fish, nitrate can also be further reduced into nitrogen gas by the use of denitrification biofilters which may create several issues, such as incomplete denitrification, resulting in toxic substances, such as nitrite and nitric oxide, or a waste of carbon source in excess. Control of the added quantity of carbon source in the denitrification biofilter is then mandatory to keep nitrate/nitrite concentrations under toxic levels for fish and in accordance with local effluent regulations, and to reduce costs related to wasted organic carbon sources. This study therefore investigates the application of different control methodologies to a denitrification reactor in a RAS. To this end, a numerical simulator is built to predict the RAS behavior and to allow for the comparison of different control approaches, in the presence of changes in the operating conditions, such as fish density and biofilter removal efficiency. First, a classical proportional-integral-derivative (PID) controller was designed, based on an SIMC tuning method depending on the amount of ammonia excreted by fish. Then, linearizing and cascade controllers were considered as possible alternatives.

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