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Advanced Metering Infrastructures (AMI) are at the base of the Smart Grid concept, as they enable, through a large deployment of metering devices, a distributed, not only energy consumption metering but also a pervasive approach to network monitoring and control. In this work we present and analyze field measurement data provided by a power network manager in order to identify routing anomalies in PLC networks that implement the G3-PLC LOADng routing protocol. In the beginning, we show different types of representations developed in order to easily visualize the network's topology and we give guidelines regarding the semantics for data structures used to describe PLC networks and their topology. We then move onto using the visual tool to incorporate routing data, to facilitate the recognition of patterns and recurring relations; considering also how the topology related to the infrastructure, we observe anomalies in the ways the protocol builds routes from nodes to the Data Concentrator. We eventually discuss how routing and geometrical properties of the topology might be related to each other.

Powerline Communications (PLC) is a popular technology providing infrastructure for applications related to IoT, smart grids, smart cities, in-home networking and has been experimentally considered for broadband access. Sensor networks and Automatic Meter Reading applications are closely related to this technology, as it provides free infrastructure and sustains the data rate requirements. The application here considered consists in the implementation of the G3-PLC LOADng routing protocol in the nodes of a sensor/meter network, where the nodes share all the same medium. G3-PLC is a powerline communication standard, employing OFDM at the physical layer and oriented at enabling the smart grid vision. The Medium Access Control implements CSMA/CA, while the Logical Link Control implements LOADng routing, which is the ITU-T G.9903 recommended specification for Lossy and Low-power Networks (LLNs).In this paper, we consider the mapping phase of the routing protocol, in which the central element of the network establishes the routes to reach any node. By simulating this process via a physical simulation tool, it is possible to synthetically train an Artificial Neural Network and teach it how the optimally established routes correlate to the topological and geometrical properties of the network. Eventually, we discuss how, by employing this AI approach, it is possible to speed-up the routing mapping process.

Traditional engineering education has been successful until the end of the 20th century. However, the fundamental technological changes of the past decade pose us the question whether this traditional education approach meets the needs of the 21st. century. It is very likely that our future engineers will have to face multidisciplinary problems, and that they will need a systemic approach to solve them. To meet these challenges it is necessary to revise the existing engineering curricula, incorporating facilities where students can design and implement projects early in the curriculum and integrated throughout, experiencing first hand how theory, computer simulation and experiments are used to develop solutions to engineering problems. This corresponds to the well known paradigm of hands-on learning. With these goals, Space Maker was created. It is a facility where students can develop their own projects, or projects proposed by faculty members as part of the courses they teach, allowing them to develop STEM (Science, Technology, Engineering and Mathematics) skills, as well as the capabilities for team work and to communicate ideas. In this paper, several projects being carried out at Space Maker by Electronic Engineering students, are described. The projects are in the areas of mobile robots and signal processing.

With innovation in network design, a strong rise in the specific performance for the end-to-end communication (capacity, latency, connectivity, etc) is expected. This paper tackles the possibility of using an artificial-intelligence-based algorithm to encompass smart routing in a network with a relatively low computation cost. The AI aspect of our method lies in the adaptability of the proposed algorithm: with the need of users and network characteristics changing in time and space, a smart, dynamic approach is required. The application of this AI is done in the specific framework of powerline communication (PLC) used as a front-hauling solution for different communication technologies. Training of the AI processor is done with synthetic data. A huge dataset is generated by using the transmission-line theory based approach to compute the capacity of a powerline link and its behavior with respect to topological information, such as disposition of nodes, their mutual distance and their overall density on the geographical territory. From this bottom-up-generated data, it is eventually possible to infer the capacity of each link in a network from its topological information, which is the only input the AI processor needs.

Nowadays, IoT and smart Grids are trending topics in research and technology applications: in fact the market for both services and products were in the hundred billions of dollars yearly in 2016. This work describes how the LoRa and G3-PLC technologies are brought together to create a hybrid sensor network testbed to deliver IoT applications in a campus of ten buildings, through an application oriented approach. The idea derives from the pursuit of creating added value in a privately owned campus, where an internal sensor network can be an opportunistic tool for the improvement of energy management, control and energy consumption metering, thus offering a better service to customers. The reader will be guided through the process steps that the team took in order to obtain the results here presented: first the architectural structure of the network will be explained, then its implementation will be described. A campaign of measurements is presented, which was carried out to test the fitness of LoRa as an outdoor connectivity technology, of PLC as an indoor solution and globally assessing the performance of our network.

Cyber-physical systems (CPS) refer to novel hardware and software compositions creating smart, autonomously acting devices, enabling efficient end-to-end workflows and new forms of user-machine interaction, in a wide range of application fields. Given their heterogeneous nature, CPS are naturally designed in the so-called simulation-centric process, where physical equipment design are translated into behavioral simulation models. Although many tools exist to ease the design phase in the different disciplines, their full integration is still an open problem. This fact holds particularly true in a control design perspective, given that in a CPS the "plant" has a heterogeneous nature, and the design of model-based, advanced control techniques would strongly benefit from the availability of a common modeling environment. In this paper, we try to enhance this simulation-centric process by introducing a pure simulation kind of prototype, based on the co-simulation of the firmware and of the multi-physical controlled system. We introduce some innovative tools, implemented in amu;Lab/CfL [1], and discuss upon their impact towards a better collaborative design and integration during the design of CPS. An example is given, taken from the HVAC (Heating, Ventilation, and Air Conditioning) field.

In the framework of the activities for the development of the Neutral Beam Injector (NBI) for ITER, the design of the MITICA device, including a plasma Source, a negative-Ion Accelerator and a Neutralizer has been recently finalized at Consorzio RFX. Among the most critical components of the plasma source are the rear vertical plates which enclose the plasma in the vicinity of the RF drivers and are hit by the back-streaming positive ions that are generated, mostly for stripping losses, inside the 1 MV electrostatic accelerator. On the basis of the physics-optical simulations of the negative-ion accelerator, the geometrical power density pattern and the energy spectrum of the back accelerated positive ions have been calculated, together with their sputtering rate on the impinged surfaces of the plasma source. The use of copper plates with an armour layer having low sputtering yield was established to be necessary for minimizing the pollution of the plasma and for preserving the component functionality. Molybdenum and Tungsten are the most suitable materials for the aim; nevertheless the minimum required thickness is approximately 0.5 mm. In order to verify the possibility of manufacturing such a thick armour layer, having a quite complex geometry and strict tolerance requirements, plasma spraying and explosion bonding techniques have been selected and investigated. The explosion bonding process has been found indeed to be the most suitable. In the paper the set up of the explosion bonding process of molybdenum on copper and the forming of the samples according to the component specifications are presented. The results of the test on explosion bonding and on plasma spraying prototypes are also reported, together with microscopic, outgassing, delamination, thermal shock, and thermal fatigue analyses. The results of the tests are presented in this paper, giving an overview on the critical technological aspects and on the still open issues in view of the manufacturing of the final components.

The Vacuum vessel of the ITER Heating Neutral Beam injector is a key component of the neutral beam system. It supports the injector components and is also an extension of the ITER Vacuum Vessel. This paper presents the status of the design of the vessel. In the first part of this paper we present the main design requirements. Besides the pressure and thermal loads, the various interfaces with other components are important constraints for the design. Some have specific requirements concerning displacement, or require specific features for their maintenance. Indeed all maintenance involving opening of the vessel needs to be performed using remote handling systems. The second part aims at presenting the present design of the NB vessel. Various concepts were studied before coming to the present design. Structures were optimised to satisfy the chosen design code (RCC-MR) under the various loading scenarios applied to the vessel, both for normal and accidental cases. In addition, the vessel incorporates two sets of long lip seals which tolerate limited displacements. Limiting the displacement is a real challenge considering the size of the flange and the forces involved. An innovative solution has been developed to improve the mechanical connection between the lids and the vessel walls in order to fulfil the requirements. The vessel displacement is also important for the alignment of the Beam Line Components with respect to the neutral beam and for the cryopumps interfaces. The geometry of the vessel was optimised to reduce the electric field stresses and to increase the voltage holding of the Beam Source, which is at 1MV potential. The present design satisfies all the requirements. The main issues have been solved, and the proposed design is now being optimised to facilitate manufacturing.

A comprehensive set of R&D activities has been carried out at Consorzio RFX regarding the construction of the grids for the ITER Neutral Beam Injectors, in order to validate the proposed manufacturing methodologies, to further develop the details of the engineering design, and to adapt existing production techniques to the specific case. In the framework of this R&D program, two Multi Channel Prototypes (MCPs) have been designed and manufactured. These prototypes feature all the possible manufacturing issues of the SPIDER grids. In fact, they reproduce the geometry of the Extraction Grid (EG) for SPIDER by having the same thickness, same cooling channels, same distributors, same aperture shape and same slots for the magnets of an EG segment. The differences from an actual EG segment regard only the dimensions, i.e. reduced width (one fourth) and height (one half). The construction and testing of these prototypes is here described in detail.

This paper focuses on the thermo-mechanical design of the ITER Neutral Beam Injector plasma, extraction and acceleration grids, considering the Radio Frequency option for the negative ion source and the SINGAP option for the accelerator. The SINGle Aperture -SINgle GAP (SINGAP) accelerator for ITER NBI foresees four grids for the extraction and acceleration of negative ions, instead of the seven grids of the Multi Aperture Multi Grid (MAMuG) reference configuration. The Radio Frequency ion source is a promising alternative to the Arc Driven one, showing very good performances in recent experiments at IPP Garching (D) and having the advantage of reduced maintenance requirements. A specific plasma grid was designed for RF source considering lower heat loads and different operational requirements. In particular the thermo-hydraulic and thermo-mechanical design aims at having all over the plasma grid a precisely controlled temperature to enhance the negative ions yield inside the caesium seeded source. Analytical and numerical (FE) thermo-mechanical analyses were also carried out for the extraction and acceleration grids. Structural verifications were accomplished according to the ITER Structural Design Criteria for In-Vessel Components. Design optimizations were performed in order to limit the misalignment of the grids within the tolerance specified by beam optics requirements (0.4 mm of maximum misalignment between corresponding apertures axes). The optimum cooling parameters under different operational scenarios were identified. The paper describes the design status of the grid system for the RF ion source and discusses in detail the numerical work carried out for thermo-mechanical and fluid dynamic behaviour.

This paper details the mechanical analyses carried out to establish the behavior of two new components of the RFX machine (copper shell assembly and toroidal support structure), under nominal and fault conditions, with particular attention to the joints and critical zones.

This paper presents a simulation study of the gate current through stacked dielectrics of interest for advanced nonvolatile memory (NVM) cells possibly employing high-k insulators to engineer the tunnel barrier. Program, retention and read disturb conditions are analyzed. The impact of modeling approximations on the predictions of the programming gate current in Fowler-Nordheim (FN) and channel hot electron (CHE) injection regimes is critically discussed. Comparison with a reference SiO/sub 2/ device allows us to identify some of the possible advantages and limitations of these stacks for future NVM.

The paper deals with the design integration of two alternative solutions for the negative ion source and accelerator of the ITER neutral beam (NB) injectors. The first alternative concerns the new 1 MV accelerator, named SINGAP, which has a single acceleration step instead of the five steps of the reference design. The second modification introduces a radio frequency (RF) negative ion source replacing the traditional filament solution. Design criteria, solutions and critical issues are presented in the paper