Dynamic Boost Based DMPPT Emulator

The Distributed Maximum Power Point Tracking (DMPPT) approach is a promising solution to improve the energetic performance of mismatched PhotoVoltaic (PV) systems. However, there are still several factors that can reduce DMPPT energy efficiency, including atmospheric conditions, the efficiency of the power stage, constraints imposed by the topology, the finite rating of silicon devices, and the nonoptimal value of string voltage. In order to fully explore the advantages offered by the above solution, the implementation of a Boost based DMPPT emulator is of primary concern, especially if it behaves as a controlled voltage or current source. The repeatability of experimental tests, the tighter control of climatic conditions, the closing of the gap between the physical dimensions of a PV array and the space available in a university lab, the simplicity with which new algorithms can be tested, and the low maintenance costs are just some of the benefits offered by an emulator. This paper describes the realization and use of a Boost based Distributed Maximum Power Point Tracking (DMPPT) emulator and shows its high flexibility and potential. The device is able to emulate the output current vs. voltage (I-V) characteristics of many commercial PhotoVoltaic (PV) modules with a dedicated Boost DC/DC converter. The flexibility is guaranteed by the ability to reproduce both I = f (V) and V = g(I) characteristics at different values of not only the irradiance levels but also the maximum allowed voltage across the switching devices. The system design is based on a commercial power supply controlled by a low-cost Arduino board by Arduino (Strambino, Torino, Italy). Data acquisition is performed through a lowcost current and voltage sensor by using a multichannel board by National Instruments. Experimental results confirm the capability of the proposed device to accurately emulate the output I-V characteristic of Boost based DMPPT systems obtained by varying the atmospheric conditions, the rating of silicon devices, and the electrical topology

THz Measurement Systems

The terahertz (THz) frequency region is often defined as the last unexplored area of the electromagnetic spectrum. Over the past few years, the full access has been the objective of intense research efforts. Progress in this area has played an important role in opening up the possibility of using THz electromagnetic radiation (T-waves) in science and in real-world applications. T-waves are not perceptible by the human eye, are not ionizing, and have the ability to cross many non-conducting materials such as paper, fabrics, wood, plastic, and organic tissues. Moreover, the use of THz radiation allows non-destructive analysis of the materials under investigation both by study of their “fingerprint” via spectroscopic measurements and by high-resolution spatial imaging operations, exploiting the see-through capability of T-waves. Such technology can be applied in diverse areas, spanning from biology to chemical, pharmaceutical, environmental sciences, etc. In this chapter, we will present the typical architecture of measurement systems based on the THz technology, detailing what are the parameters that define their performance, the measurement methods, and the related errors and uncertainty, and focusing at the end on the use of time-domain spectroscopy for the evaluation of different material properties in this specific frequency region

Low-cost multi-channel synchronous data acquisition system based on compressive sampling approach

Peer Reviewe

A Superconducting Permeameter for Characterizing Soft Magnetic Materials at High Fields

Asuperconductingpermeameterisproposedtocharacterizethemagneticpropertiesofhigh-energysuperconducting magnet yokes at their operating temperatureand saturation level. The main problem of superconductingcoils, an undesired quench, was faced by specific protectionsimulations, which has led to a self-protected system. Thesuperconducting permeameter was used to perform the magneticcharacterization of ARMCO Pure Iron, the material for the newHigh-Luminosity Large Hadron Collider (HL-LHC) supercon-ducting magnet yokes, which was performed at the cryogenictemperature of 4.2 K and a saturation level of nearly 3 T.Two case studies based on the new HL-LHC superconductingquadrupole and dipole magnets highlight the impact of themagnetic properties of the yoke on the performance of thesuperconducting magnets, showing that the common assumptionthat heavily saturated steels with similar chemical compositionbehave precisely the same way has been proven wrong

Linee guida per il Bilancio di Genere negli Atenei italiani

l Bilancio di Genere è un documento che, da un lato, fotografa la distribuzione di genere delle diverse componenti all’interno dell’Università nonché la partecipazione di donne e uomini negli organi di gestione dell’Ateneo e, dall’altro, monitora le azioni dell’Ateneo a favore dell’eguaglianza di genere, e valuta l’impatto di queste e delle politiche dell’Ateneo, compresi gli impegni economici-finanziari, su donne e uomini. Il Bilancio di Genere è dunque uno strumento essenziale per realizzare l’eguaglianza di genere nelle Università e per integrare la prospettiva di genere in tutte le politiche dell’Ateneo. L’importanza di portare la questione di genere al centro dell’attenzione degli Atenei, è evidente se si considera che in Italia, le donne rappresentano solo il 20 % dei professori ordinari e, tra i Rettori italiani, solo il 7% sono donne. Le forbici che descrivono le carriere di donne e uomini all’interno degli Atenei provano inoltre il c.d. fenomeno del “tubo che perde”: al progredire della carriera universitaria, il numero di donne diminuisce e l’Università perde le relative risorse. La diseguaglianza di genere causa dunque un problema di perdita di capacità e cattivo utilizzo di risorse pubbliche. La CRUI ha da tempo intrapreso un percorso a favore della tutela dell’eguaglianza tra donne e uomini nelle Università e ha assunto un impegno preciso per implementare e monitorare la diffusione e l’utilizzo del Bilancio di Genere quale strumento fondamentale per inserire la parità di genere nella più ampia strategia di sviluppo degli Atenei. A tal fine, ha dato mandato a un Gruppo di lavoro di esperte di elaborare le linee guida e la metodologia per realizzare il Bilancio di Genere delle Università e facilitare, così, una sua capillare diffusione tra gli Atenei italiani. Il volume illustrata nel dettaglio il processo di redazione del Bilancio di Genere - dalla costituzione del gruppo di lavoro, sino alla diffusione degli esiti del Bilancio di Genere - qual è il suo contenuto - mediante la individuazione di ambiti e fenomeni da analizzare con l’identificazione dei corrispondenti indicatori e delle relative rappresentazioni - e come il Bilancio di Genere debba essere adoperato come strumento di governance dell’Ateneo, attraverso l’integrazione con i principali documenti di programmazione e rendicontazione, al fine di promuovere l’eguaglianza sostanziale all’interno degli Atenei

On the Suitability of Augmented Reality for Safe Experiments on Radioactive Materials in Physics Educational Applications

Laboratory experiences have proved to be a key moment of the educational path in most of the so-called Sciences, Technology, Engineering and Mathematics (STEM) subjects. Having the opportunity of practicing on actual experiments about the theoretical knowledge achieved during the classroom lectures is a fundamental step from a didactic point of view. However, lab activities could be forbidden in the presence of tests characterized by safety issues, thus limiting students' cultural growth; this is particularly true for physics experiments involving radioactive materials, sources of dangerous radiations. To face the considered problems, the authors propose hereinafter a mixed-reality solution involving augmented reality (AR) at students-side and actual instrumentation at laboratory-side. It is worth noting that the proposed solution can be applied for any type of experiment involving the remote control of measurement instruments and generic risk conditions (physical, chemical or biological). As for the considered case study on gamma radiation measurements, an ad-hoc AR application along with a microcontroller-based prototype allows students, located in a safe classroom, to (i) control distance and orientation of a remote actual detector with respect to different radioactive sources and (ii) retrieve and display on their smartphones the corresponding energy spectrum. The communication between classroom equipment and remote laboratory is carried out by means of enabling technologies typical of Internet of Things paradigm, thus making it possible a straightforward integration of the measurement results in cloud environment as dashboard, storage or processing

Transient analysis in non-linear systems through the Huang Hilbert Transform

The paper deals with the use of the Huang Hilbert Transform (HHT) for the analysis of transient signals in non linear circuits. Differently from traditional methods that decompose a signal as the sum of apriori adopted waveforms, HHT procedure decomposes the signal of interest in oscillatory modes aposteriori determined, in dependence on the signal characteristics, giving, thus, a better information about the physical characteristics of the observed system. The performance of the proposed analysis method has been evaluated by applying the HHT to the current acquired from an actual RLC circuit during its free natural oscillation. The circuit involves a saturable inductor, therefore the HHT capability of providing physically meaningful information accounting for both non stationarity and non linearity has been appreciated

VR, AR, and 3-D User Interfaces for Measurement and Control

The topics of virtual, mixed, and extended reality have now become key areas in various fields of scientific and industrial applications, and the interest in them is made tangible by the numerous papers available in the scientific literature. In this regard, the Special Issue “VR, AR, and 3-D User Interfaces for Measurement and Control” received a fair number of varied contributions that analyzed different aspects of the implementation of virtual, mixed, and extended reality systems and approaches in the real world. They range from investigating the requirements of new potential technologies to the prediction verification of the effectiveness and benefits of their use, the analysis of the difficulties of interaction with graphical interfaces to the possibility of performing complex and risky tasks (such as surgical operations) using mixed reality viewers. All contributions were of a high standard and mainly highlight that measurement and control applications based on the new models of interaction with reality are by now increasingly ready to leave laboratory spaces and become objects and features of common life. The significant benefits of this technology will radically change the way we live and interact with information and the reality around us, and it will surely be worthy of further exploration, maybe even in a new Special Issue of Future Internet