Anaerobic membrane bioreactors have become an environmentally friendly solution for wastewater treatment. The lack of sufficiently accurate mathematical procedures to model their behaviour and the fouling process of the membranes, poses a challenge when trying to optimise their energy consumption and maintenance costs. An accurate model of the fouling process of the membranes is critical to make the most of this technology. This is a perfect scenario in which to introduce neural networks (NN) as an alternative to mathematical modelling. However, the duration of the experiments and the difficulties in measuring some relevant variables, make it hard to collect high quality datasets to train the NN. Our goal is to obtain a good prediction of the fouling status of the membranes to enable an adjustment of operation conditions and maintenance procedures ahead in time. To do so we must obtain high quality datasets to train our neural networks. The combination of static and dynamic networks enables us to leverage the best prediction capabilities of each one. This combination requires a preprocessing of the datasets that separates trends from oscillations. The outputs obtained need to be put together to build up the predicted evolution of fouling. Accurate predictions are then extended from 25 to up to 75 filtration cycles. To maintain and even extend accuracy after sudden changes in operating conditions, retraining the NN every 25 cycles is proposed. AI based real time predictions open a new scope for decision making, and optimisation in the field of anaerobic membrane reactors.

Many current parallel computers are built around a torus interconnection network. Machines from Cray, HP, and IBM, among others, make use of this topology. In terms of topological advantages, square (2D) or cubic (3D) tori would be the topologies of choice. However, for different practical reasons, 2D and 3D tori with different number of nodes per dimension have been used. These mixed-radix topologies are not edge symmetric, which translates into poor performance due to an unbalanced use of network resources. In this work, we analyze twisted 2D and 3D mixed-radix tori that remove the network bottlenecks present in nontwisted ones. Such topologies recover edge symmetry, and consequently, balance the utilization of their links. The distance-related properties of twisted tori together with a full characterization of their bisection bandwidth are described in this paper. A simulation-based performance evaluation has been carried out to assess the network performance under synthetic and trace-driven workloads. The obtained results show noticeable and consistent performance gains (up to an increase of 74 percent in accepted load). In addition, we propose scalable and practicable packet routing mechanisms and wiring layouts for these interconnection systems. The complexity of the architectural proposals is similar to the one exhibited by routing and folding mechanisms in standard tori.

Many parallel computers use Tori interconnection networks. Machines from Cray, HP and IBM, among others, exploit these topologies. In order to maintain full network symmetry, 2D and 3D Tori must have the same number of nodes (k) per dimension resulting in square or cubic topologies. Nevertheless, for practical reasons, computer engineers have designed and built 2D and 3D Tori having a different number of nodes per dimension. These mixed-radix topologies are not edge-symmetric which translates into poor performance provoked by an unbalanced use of the network links. In this paper, we propose and analyze twisted 2D and 3D Tori which remove the network bottlenecks present in mixed-radix standard Tori. These new topologies recover edge-symmetry and, consequently, balance the utilization of their links. We describe the distance-related parameters of these twisted networks and use simulation to asses their performance under synthetic loads. The obtained results show noticeable and consistent performance gains. In addition, we propose scalable and practicable packet routing and folding techniques for these interconnection subsystems. The complexity of the resulting architectural solutions is similar to the one exhibited by traditional routing and folding mechanisms employed in standard Tori. This fact together with the performance improvements obtained could justify the use of these twisted topologies in the future.