Emergence of winner-takes-all connectivity paths in random nanowire networks

Nanowire networks are promising memristive architectures for neuromorphic applications due to their connectivity and neurosynaptic-like behaviours. Here, we demonstrate a self-similar scaling of the conductance of networks and the junctions that comprise them. We show this behavior is an emergent property of any junction-dominated network. A particular class of junctions naturally leads to the emergence of conductance plateaus and a “winner-takes-all” conducting path that spans the entire network, and which we show corresponds to the lowest-energy connectivity path. The memory stored in the conductance state is distributed across the network but encoded in specific connectivity pathways, similar to that found in biological systems. These results are expected to have important implications for development of neuromorphic devices based on reservoir computing

Microfluidic manufacturing of phospholipid nanoparticles: Stability, encapsulation efficacy, and drug release

Liposomes have been the centre of attention in research due to their potential to act as drug delivery systems. Although its versatility and manufacturing processes are still not scalable and reproducible. In this study, the microfluidic method for liposomes preparation is presented. DMPC and DSPC liposomes containing two different lipid/cholesterol ratios (1:1 and 2:1) are prepared. Results from this preparation process were compared with the film hydration method in order to understand benefits and drawbacks of microfluidics. Liposomes characterisation was evaluated through stability studies, encapsulation efficacy and drug release profiles of hydrophilic and lipophilic compounds. Stability tests were performed during 3 weeks and the liposomes properties of the most stable formulations were determined using Infrared Microscopy and Atomic Force Microscopy. Microfluidic allows loading of drugs and assembly in a quick single step and the chosen flow ratio for liposomes formulation plays a fundamental role for particle sizes. One hydrophilic and one lipophilic compounds were incorporated showing how formulation and physic-chemical characteristics can influence the drug release profile

A junction level study of the activation process in nanowire networks

Nanowire networks are promising memristive architectures for neuromorphic computing applications due to their connectivity and neurosynaptic-like behaviours. In this PhD thesis, we demonstrate a self-similar scaling 1 of the conductance of networks and the junctions that comprise them. As a result, we introduce a dynamic memristive model 2, based on tunnelling conduction, this model is capable of describing the growth of conductive filaments within the nanowire junctions and consequently the connectivity evolution of the networks. Through the interplay of experimental results and simulations, we demonstrate how a particular class of junctions leads to the emergence of conducting paths which we define as \u27winner-takes-all\u27 (WTA) paths. The emergence of these electrical paths is characterized by particular conductance plateaus and by the fact that they represent the most efficient way to transfer the information through networks. These results point to the possibility of independently addressing memory or conductance states in complex systems and is expected to have important implications for memory and neuromorphic computing devices

On the Influence of Mooring in Wave Energy Converters Productivity: the PeWEC case

The aim of the present study is to analyze the impact of the mooring system on the power extraction of a WEC (Wave Energy Converter). A comparison has been carried out between the scenarios of non moored hull and moored hull: for the latter case, the mooring system dynamics has been evaluated by means of a Deep Neural Network, which compares the time histories of two identical simulations (one with the mooring and the other without). This has allowed to include the influence of the mooring on the equations of motion of the hull. By coupling the equations of motion of the device with the equations of the Power Takeoff (PTO), it was possible to estimate the productivity of the WEC system for a given sea state. The results on productivity for various sea states were then compared in order to make some considerations on the influence of the mooring on the operational conditions of the system. In a future perspective, this methodology can be used as a tool for design and evaluation of mooring systems for WEC systems