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The operators of the railway industry (i.e., Traction System and Railway System Operators) are currently involved in a major process of energy transition. Aimed at improving both environmental sustainability and energy efficiency, technological infrastructures are being updated and new operating solutions studied. Moreover, the business opportunities offered by the new rail market are forcing operators to search for power quality solutions. In this paper, an efficiency strategy is proposed for optimally moving a fleet of trains while taking power quality indices into account. A method to relate the traction power requirements to the electrical variables of the railway infrastructure is formulated in terms of the power flow approach. Our numerical simulations focus on the real case of the Metro Line 1 in the southern Italian city of Naples. The energy problem of moving the trains on the track is solved by including a set of constraints at the point of common interaction between railway market operators. Specifically, repetitive train starts and their speed profiles are optimally managed in terms of power requirements at traction power substations by using power quality constraints. This strategy allows improvements in energy efficiency without compromising the quality of the railway service.

As a consequence of the growing demand for mobility and the requirements for reduced environmental pollution, railway traction systems are receiving increasing interest. Researches are analyzing new technologies and managing solutions to increase energy efficiency in the railway infrastructures. Many studies proposed the oppor-tunity to introduce the technology of energy storage systems (e.g., Wayside Energy Storage Systems - WESS) in traction infrastructures. WESS can be able to: i) reduce voltage drops; ii) save braking energy; iii) support Traction Power Substations in supplying traction power peaks. A relevant topic in using WESSs in railway infrastructure is to verify their impact in case of faults. Studies on short circuit analyses are required to verify the correct rating of the protection devices and the opportunity to use new protection devices and mode of operating, when the new technology is integrated. In this paper, the typical Italian DC railway power system is investigated. Specifically, the contribution of WESS to the short circuit currents is assessed by examining transient and steady-state conditions.

Electrified railway systems are the current focus of energy efficiency studies due to the increasing constraints of environmental sustainability policies. Railway System Operators (RSOs), also encouraged by market deregulation, are thus examining how to update infrastructures and vehicles and/or apply new operating strategies. Given the intrinsic relation between railway systems and their primary feeding grid, each measure applied to a railway system impacts directly on the power grid which supplies the system. Against this background, this paper aims to ascertain the impact of an energy efficiency strategy applied by the RSO system on its primary grid. The energy-efficient strategy is identified as to preserve timetable stability and service quality in a passenger-oriented perspective. Moreover, a method to model the interaction between the systems in terms of power flow exchanges is proposed. The model is used to verify how an eco-driving technique applied to a metro system affects the state variables of the distribution grid. In particular, the primary grid, the traction power substations and the railway system are modelled according to real data. The case study is the Metro Line 1 operating in the city of Naples (Italy). The numerical simulations are carried out with a two-step procedure: first, the power requirements of the rolling stock as a function of the imposed operating service are calculated by OpenTrack ® software; the state variables of the distribution grid are then evaluated by means of the power flow approach.

The scientific literature is paying particular attention to Ultra-Fast Charging Stations (UFCSs) that can make charging times of Electric Vehicles (EVs) comparable with the refuelling time of internal combustion engine vehicles. In this context, scheduling charging algorithms to manage the available resources deserve significant attention. This paper proposes an online scheduling algorithm for UFCSs equipped with Battery Energy Storage Systems. The charging profile is obtained by considering the power and energetic constraints related to both infrastructure and EVs. The constraints are assessed according to the efficiency of the infrastructure, for which a power losses estimation approach was proposed and then detailed for the UFCS realized at our department. Even, the dependence of the maximum EV charging rate on the State of Charge (SoC) is considered. These aspects are usually neglected. Thus, starting from the measurements of the maximum charging rate for two commercial EVs, numerical simulations were performed using the proposed algorithm according to two different scheduling policies, i.e., the not-preemptive ‘First Come Best Served’ and the preemptive ‘Round Robin SoC’. The numerical results highlight the difference between the two policies regarding the allocation of resources among vehicles and how the SoC of the BESS affects the overall charging profiles.

Light rail vehicles with onboard energy storage systems have gained increasing interest due to higher efficiency and lower or null local emissions in catenary-less operation. Their traction circuit conventionally employs inverters to drive the traction motors and DC/DC converters to manage the onboard sources. Recently, the concept of multi-source inverter (MSI) was introduced for single-stage integration of AC loads and multiple DC sources without. This paper evaluates the feasibility and attractiveness of the MSI for single-stage integration of batteries and supercapacitors to the traction motors in a catenary-less tramway vehicle. The configuration of the MSI-based hybrid energy storage system is detailed. Numerical simulations are carried out to assess its performance over a typical driving cycle. Furthermore, the proposed architecture is compared to a standard configuration employing a DC/DC converter to control the supercapacitors, with focus on power losses and volumes of the converters and DC sources.

Railway industry is experiencing a strong need of renewal and smart technology. Hence, advanced approaches are needed to improve efficiency and sustainability of railway operations. In urban contexts, the public railway sector is object of an inevitable process of revamping, which involves expectations of end-users, railway operators, local supply distributors or local authorities. This paper examines an urban railway power system, where a smart scenario is envisaged. Particularly, an Italian AC/DC railway power infrastructure is considered, and an energy efficiency strategy is assumed. Aim of the paper is to evaluate the voltage quality in the supplying distribution network for any operating conditions of the railway system. Also, the energy efficiency strategy is arranged to improve voltage quality. More specifically, the strategy exploits electrical energy storage systems recharged by regenerative braking of rolling stocks in order to increase efficiency of the whole system. Also, the storage system allows shaving the peak load demand aimed at improving the voltage quality. Numerical simulations are carried out, they provide power quality analysis by examining nodal voltages as a function of the efficiency measure. The behavior of the railway power system has been analyzed under different operating conditions.

High Voltage (HV) overhead power lines are systems of interconnected elements that deliver massive amounts of electrical energy over long distances. Electrical conductors, used as energy carriers, are designed according voltage, current, and temperature rated value. Monitoring the power line's state variables is emerging as a crucial topic aiming at both determining the optimal real-time capability and defining a suitable model for Health Index assessment. A Wireless Sensor Network (WSN), consisting of many distributed sensor nodes that communicate with each other, can be a suitable tool to improve line ampacity by maintaining the operating variables in respect of their rated values. This paper investigates the design of an Energy Management System (EMS) for a wireless sensor for HV power line application and proposes a maximum power point tracker (MPPT). The behavior of the MPPT is discussed in terms of electromagnetic field laws and properties of magnetic materials. Ordinary and extraordinary operating conditions are investigated. The theoretical results are validated through a series of experimental tests. A prototype has been realized and tested for real operating currents. The tests are also used to verify the sensor's resilience in the presence of harsh fault conditions.

The number of Plug-in Electric Vehicles (PEVs) available on the car market is continuously growing. The electrification of the mobility is definitely related to the diffusion of the charging infrastructures widely distributed on the territory. Indeed, PEV owners request for charging stations able to offer features adequate to the expectations. They are expected to be able to recharge vehicle's on-board battery in a ten of minutes. In this paper, Ultra Fast Charging Stations (UFCSs) are investigated. The stations are discussed in terms of electric schemes and modalities of control. There is a focus on components, systems, state variable and security level. Moreover, the UFCS realized at the University of Naples Federico II is highlighted. The lab prototype is discussed in terms of configuration and rated values. The results of some numerical tests are carried out. They point out both the main features of the charging slots and the requirements of load emulators for UFCS.

In Xylella II the CJEU was called upon to assess whether Italy had failed to meet the obligations stemming from the Plant Health Directive and Decision 2015/789/EU, aiming to inhibit the spread of the plant pathogen Xylella fastidiosa in Apulia (Southern Italy). In carrying out its review, the Court relied to a large extent on the scientific evidence submitted by the Commission. It found that the Member State had failed to properly remove infected plants and monitor the presence of the pathogen in the 20km strip dividing the infected zone from the buffer zone. However, the Court also confirmed that in proceedings brought under Article 258, the burden of proof lies on the Commission, which may not rely on any presumption to demonstrate the State’s failure to meet EU law obligations. The Italian authorities are now expected to comply with the Court’s ruling, as financial sanctions may be imposed at a later stage.

Power-forecasting model is a relevant topic in modern power systems. This is due to the wide integration of Renewable Energy Sources (RESs) and their not predictable production. To face this issue, the paper presents a comparison between the performances of the traditional Autoregressive (AR) statistical method and the more recent Artificial Neural Network (ANN) method. The comparison is applied in forecasting of the most significant RES present in the Sicily zone (Italy), i.e., solar sources. To this aim, using the data of Gestore Servizi Energetici (GSE), both the AR and ANN architectures are built by exploiting the information available in time period 2010 - 2015 in terms of temperatures and solar irradiation, thus obtaining a power forecasting for 2016 for each country of the Sicily zone. The performances of the two different methods are compared on the basis of both Root Mean Square Error (RMSE) and Mean Absolute Percentage Error (MAPE) values. These two indexes are used to evaluate the accuracy of the proposed models.

ArcStereoNet is a new ArcGIS® based toolbox for stereographic projections that we implement here using Python 2.7 programming language. The reason to develop another stereographic projection package arises from the recent use of Python as an exclusive programming language within the ArcGIS® environment. This permits a more flexible approach for the development of tools with very intuitive GUIs, and also allows the user to take full advantage of all potential GIS mapping processes. The core of this new projections toolbox is based on the capability to easily apply and compare most of the commonly used statistical methods for cluster and girdle analysis of structural data. In addition to the well-known Fisher, K-means, and Bingham data elaborations, a completely new algorithm for cluster analysis and mean vector extraction (Mean Extractor from Azimuthal Data), was developed, thereby allowing a more reliable interpretation of any possible structural data distribution. Furthermore, as in any other GIS platform, users can always precisely correlate each single projected data point with the corresponding geographical/locality position, thereby merging or subdividing groups of structural stations with a simple selection procedure. ArcStereoNet also creates rose diagrams, which may be applied not only to fault/joint planes orientation data, but also for the analysis of 2D microstructural fabric parameters. These include geometrical datasets derived from the minimum bounding approach as applied to vectorized grains in thin sections. Finally, several customization settings ensure high-quality graphic outputs of plots, that also allow easy vector graphics post-processing.

Typically, in partial discharges (PD) diagnostics tests carried out in a laboratory, harmonic content in a voltage waveform is ignored. However, during the operation of variable-frequency drives (VFD)-fed electric motors, the distorted voltage waveform is produced due to the addition of harmonics components in the sinusoidal voltage waveform. The distortion level increases when the VFD is operated at a lower speed ratio. The additional spectral components in the applied voltage waveform can have a significant impact on the PD behavior in the insulation of the electric motor. Therefore, during online PD monitoring, overlooking the harmonic regime in the applied voltage may lead to a false interpretation of PD data. This article investigates the influence of voltage harmonics distortion produced during the variable-speed operation of VFD on PD characteristics. For this purpose, online PD measurements have been carried out by performing a series of experiments on eight VFD-fed motors under variable operating conditions. The PD severity at different harmonic compositions is experimentally investigated by determining various PD characteristic parameters including PD inception voltage, accumulated apparent charge, average discharge current, discharge power, and quadratic rate. Also, two terms Gaussian models have been mathematically developed using 288 data samples to quantify the variations in PD characteristic parameters against distortion parameters. The article proposes a framework for properly evaluating harmonics impact in PD for electric motors and correctly estimating stator insulation degradation.

Nowadays, simple and non-destructive methods able to recognize pathogens in real time and in living tissues are still missing. This study has been designed to evaluate the presence of fungi (i.e. Gnomoniopsis spp.) in chestnuts. To this aim, a measurement setup based on terahertz radiation has been used to highlight the presence of fungal diseases in chestnut samples. A population of fifty chestnuts that was known to be partially infected by Gnomoniopsis spp., has been imaged in the low terahertz range by a compact and portable active imaging system equipped with a 100 GHz (0.1 THz) source. The relationship between the chestnut physical parameters, such as mass or volume, and the light attenuation in healthy and infected fruits has been tentatively explained by assuming a different water density and a different physical structure in healthy and unhealthy fruits, due to carbohydrates hydrolysis by the fungi. The preliminary results here described suggest that the sole analysis of the light attenuation combined with the measurement of weight or volume of a chestnut can provide an immediate indication of the presence of fungi in the fruits.

Due to the liberalization of the railway sector, Railway System Operators (RSOs) are involved in the renewal of railway systems in terms of both technological and managing improvements. They are evaluating how new strategies can improve energy efficiency and operating sustainability. This paper proposes the optimal management of a fleet of metro trains in terms of power key performance indicator (KPI). To control the regularity of the railway service assuming a constant Headway value, there were examined how the optimal assignment of the Layover time between the two terminal stops can be managed concerning the maximum power requirements at the Traction Power Substations (TPSs). The numerical application focused on the traction power system of Metro Line 1 of Naples (Italy). The results highlighted the evaluation of the power peaks required to the distribution grid as a function of the Layover time assignment.

We apply Quantitative Microstructural Analysis (QMA) to a selection of mylonitic rocks that originate from different protoliths, ranging from tonalite to skarn and passing through migmatitic paragneiss. These rocks, that at the end of Paleozoic originally belonged to the lower crustal portion of the southern European Variscan chain, were successively involved in deep-seated strike-slip kinematics of the western Mediterranean realm, created by the relative movement in the Paleocene of the African-European colliding plates. This geodynamics leads to the roto-translation of the Sardinia-Corsica block and the drifting of the kabilo-clabride microplate system (Cirrincione et al., 2015). Remnants of these high strain-rate strike-slip zones are characterized by rheological behaviours controlled by the selective activation of their specific interconnecting weakening phase, as well as by the rheology and abundance of porphyroclasts. QMA is generated by means of new semi-automated GIS-based tools that allow us to extrapolate statistically meaningful kinematic and rheological properties of this meso-Alpine strike-slip mylonitic shear zone (i.e. Palmi Shear Zone). This, in turn, constrains the Alpine evolutionary stages of southern Calabrian geodynamics (Ortolano et al., 2020). Semi-automated image analysis of mXRF maps, combined with high-resolution thin-section scans involving new GIS-based tools developed for structural analysis (e.g. Ortolano et al., 2018; Visalli, 2018), was performed on a selection of three different mylonitic rock-types. These tools permit the user to quantitatively extrapolate rock-fabric parameters such as grain size, aspect ratio and orientation, which allows the nature and relative percentage of the weakening vs. hardening layers, as well as their kinematics, to be derived. Our results allow us to distinguish the porphyroclastic domain levels constituted alternatively by feldspar, amphibole, pyroxene or scapolite, from the weakening phase ones dominated by quartz, biotite plus quartz, or by calcite when the weakening layer is controlled by skarns. Image analysis of porphyroclastic domains has been used to infer the dominant shear-type through Rigid Grain Analysis, revealing a pure shear component of 66 to 68 % for the mylonitic tonalites; 62 to 66 % for the mylonitic paragneisses; and 58 to 62 % for the mylonitic skarn. Image analysis conducted on quartz-rich domains allows an estimate of the shear strain rate, which ranges on average from 1.14*10-12 (1/s) for mylonitic paragneiss to 5.91*10-12 (1/s) for mylonitic tonalite, and is in accord with high strain zones in natural settings. Our results provide new insights into the kinematics and rheology of this exhumed relic of the deep-rooted early-Alpine strike-slip tectonics of the western Mediterranean. ReferencesCirrincione R., Fazio E., Fiannacca P., Ortolano G. & Pezzino A., Punturo R. 2015. Period. Mineral., 84(3B), 701-749.Ortolano G., Visalli R., Godard G. & Cirrincione R. 2018. Comput. Geosci., 115, 56-65.Ortolano, G., Fazio, E., Visalli, R., Alsop, G.I., Pagano, M., Cirrincione, R. 2020. Journal of Structural Geology, 131, art. no. 103956.Visalli R. 2018. Plinius, vol 44, DOI:10.19276/plinius.2018.01014.

Storage technologies devices are very interesting solutions for improving energy saving and guaranteeing contemporaneously to enhance the electrical characteristics of Light Rail Transit (LRT) systems. Onboard Energy Storage System based on Lithium Ion Capacitor (LiC) devices represent a viable engineering solution for energy saving optimization. The authors suggest a multi-objective design optimization procedure based on catenary and storage power losses minimization. A test characterization of ESS has been presented in order to use the better appropriate modeling of LiC for the examined case study. The numerical simulation allows to confirm the feasibility of the proposed design procedure.

This paper deals with the modelling of the 2 × 25 kV – 50 Hz high speed railway supply system. The proposed approach extends the traditional multi-conductor transmission line approach typically used for high speed railway systems, which is based on the assumption of overhead conductors. More specifically, this approach models the system by considering the presence of both overhead and buried conductors. Analytical formulations to calculate self and mutual line parameters are used. A numerical simulation allows evidencing the different results when the simplified and the detailed modelling approaches are adopted. A sensitivity analysis to point out the influence of the finitely conductive ground is also proposed.

Joined Cases C-78/16 and C-79/16, Giovanni Pesce (et al) v Presidenza del Consiglio dei Ministri, [2016] EU:C:2016:428.In Xylella, the Court of Justice of the European Union (CJEU) was called upon to assess how far policymakers can go in conditions of scientific uncertainty, and whether EFSA opinions can be indirectly subject to judicial review, despite not being legally binding. In particular, the Xylella case highlights the relevance of EFSA’s scientific authority over the Commission: since EFSA opinions are not directly reviewable by the CJEU – as they constitute an intermediate stage of a more complex administrative procedure – the political and legal liabilities relating to EFSA assessments are entirely shifted onto the Commission, whose discretion is reviewable by the EU judiciary. In this regard, the Xylella case confirms how difficult the judicial review of precautionary measures can be. It shows once again that a full assessment of these measures is impossible, as scientific uncertainty restricts the grounds for judicial review to the manifest appropriateness of the contested measures and the availability of less onerous and equally effective measures.

Worldwide expectancy of larger fleets of PEVs requires an increasing number of available fast and ultra-fast charging stations. In order to reduce the impact on the distribution grid of the power demand of large fleets of PEVs, the coordination of charging in stations equipped with multiple charging slots is mandatory. The paper suggests a smart charging profile of electrical vehicles based on an optimization problem in order to minimize the charging time. Constraints in term of limits on the power supplied by DSO, the available state of charge (SOC) of the BESS and the energy requested by the PEVs are taken into account. Some simulations are presented to validate the suggested charging strategy.

Recent improvements in shipboard systems focus on the use of new technological systems and the adoption of innovative operating strategies for both increasing energy efficiency and reduce gas emissions. In such a context, this article studies a ship power system, where an energy storage system and a tailored energy management system are applied. It focuses on a detailed model of the on-board power system and points out a scenario of analysis larger than those usually adopted in the literature. The model is carried out with reference to DC, AC and hybrid AC/DC power grid architectures, by means of a power flow approach. The strategy of the energy management system optimally controls the on-board power system integrated with a battery storage device. The strategy aims to minimizes fuel consumption of the prime movers, while satisfying time-varying load demand under different operating scenarios. The procedure, tested on actual operative conditions of a supply vessel, shows feasibility and effectiveness of the power flow approach, giving evidence to the reduction of fuel consumption, while the correct operation of the power system is guaranteed.

Today, electrified railway systems are involved in renewal processes, which address vehicles, wayside infrastructure and management of fleet of rolling stocks. Railway System Operators (RSOs) test how novel and innovative strategies impact of their own systems in order to reach energy efficiency targets. Due to the intrinsic interaction between the railway traction system and its primary grid, the feasibility of each innovative strategy has to be evaluated in terms of energy and power not only on the railway traction system, but also on its feeding grid. In the actual context forced by the constraint of Covit-19 virus, one of the more relevant strategies applied to urban railway systems is to operate the railway traction system with reduced values of headway. This strategy, which forces repetitive starts, in some cases contemporaneous, of rolling stocks, can produce severe voltage drops on the primary distribution grid. This paper proposes of examining the motion of a fleet of metro trains on a traction system fed by a MV distribution grid of reduced short circuit value. The numerical results point out how constraints imposed by the distribution grid at the Traction Power Substations can influence the control of moving the fleet of rolling stocks on the track.

Quantitative microstructural investigations involving new GIS-based tools are applied to three different types of mylonitic rocks. These techniques enable mineral shape distribution maps to be produced, thereby allowing the nature and relative percentage of the weakening vs. hardening layers, as well as their kinematics, to be obtained within a statistically meaningful dataset. Selected rock-types are derived from shearing associated with the meso-Alpine strike-slip tectonics of the western Mediterranean realm, which since the Paleocene has involved, skarn, migmatitic paragneiss and tonalites. These rocks belong to a deep-seated portion of the original southern European Variscan chain known as the Calabrian Pelortani Orogen. Microstructural maps reveal porphyroclastic domains, represented alternatively by feldspar, amphibole, pyroxene or scapolite, that can be distinguished from weakening phase areas, characterised by quartz, biotite plus quartz, or alternatively by calcite when the weakening layer is controlled predominantly by skarns. Image elaboration of porphyroclastic domains was employed to estimate the dominant shear-type, with Rigid Grain Analysis, indicating a pure shear component of 66–68% for the mylonitic tonalites; 62–66% for the mylonitic paragneisses; and 58–62% for the mylonitic skarn. Grain boundary mapping of the quartz-rich domains also permits an estimate of shear strain rate, which ranges from 1.14*10−12 (1/s) for mylonitic paragneiss to 5.91*10−12 (1/s), for mylonitic tonalite, and is in accord with high strain zones in natural settings. Finally, our results opened up new perspectives in the interpretation of the kinematics and rheology of this exhumed sector of the southern European Variscan chain reflecting the deep-seated meso-Alpine strike-slip tectonics of the western Mediterranean realm.

Proper management of railway systems is currently mandatory in order to reach energy saving objectives that positively impact on both the internal railway system and its supplying power system. In such a context, the railway system has to be analyzed in terms of both structure renewal and energy efficiency strategies, including measures ranging from the eco-driving techniques to the energy recovery. The choice of the more appropriate measures to be implemented depends on the type of system under study, because diverse responses can be obtained for different system as a function of the technological characteristics and the imposed operating assignments. Therefore, the availability of tools able to accurately describe the behavior of a system characterized by high level of complexity phenomena becomes a fundamental instrument to assess the impact of alternative measures. Railway are complex systems, which depend of logistics, mechanical and electrical elements. These aspects are all together integrated in order to meet the expected requirements of customers. Motivated by above, this paper proposes a novel train-simulator developed in Simulink-MatLab framework. The proposed simulator calculates train dynamics and energy absorption for an assigned observation time. It performs the resolution of the motion equation for a rolling stock moving on assigned track and operating conditions. One of the advantages of the proposed simulator is its ability to be easily update to different type of railway systems as well as eco-driving techniques. In this paper, the simulator was tested on an urban metro system operating in the North of Italy.

The study of leaf vascular systems is important in order to understand the fluid dynamics of water movement in leaves. Recent studies have shown how these systems can be involved in the performance of photosynthesis, which is linked to the density of the vascular network per unit of leaf area. The aim of the present study was to highlight the correlation between a leaf vein density (VD) and net photosynthetic rate (P N), which was undertaken using a digital camera, a stereoscopic microscope, and a light source. The proposed hypothesis was tested, for the first time, on the leaves of two cultivars of Vitis vinifera (L.). A significant difference was found between the VD of mature leaves of the two cultivars. VD was also significantly correlated with the maximum leaf P N. These findings support the hypothesis that the vascular system of grape leaves can be correlated with leaf photosynthesis performance.

This paper examines the management of ship power systems equipped by energy storage systems. Energy storage in the on-board power system can increase the efficiency of prime movers in order to reduce fuel consumption and pollutant emissions. In this paper, a management strategy for the on-board electrical network is proposed. The strategy optimally balances the charge/discharge of the storage device, the power of the generation system, the loads’ demand of hotels, auxiliaries, and electrical machineries used for propulsion and maneuvering purposes. The optimal approach aims at minimizing the fuel consumption, while technical constraints of the on-board system are considered in terms of both generation system and energy storage system. A case study of a real off-shore supply vessel is proposed. The results of the numerical application are discussed showing the effectiveness of the proposed strategy.

Today, in the railway sector there is considerable interest in studying the best ways of exploiting train braking energy, in order to achieve a reduction in energy costs and better stabilisation of grid voltage. Among the various on-board or wayside measures proposed, one of the most promising solutions is based on using wayside energy storage systems (WESSs). A WESS is a storage installation which can be integrated into mass transit systems in urban areas as well as into long-distance railway lines. It can operate as a smart storage system able to provide relevant benefits in terms of recovering surplus regeneration braking energy, voltage stabilisation, reduction of peak power demand. For these purposes, an effective and flexible simulator is essential to provide all the elements needed to focus and compare feasible configurations and operations. This study examines the problem of introducing the WESS technology in real railway infrastructure. It proposes a method based on a simulator of the WESS system integrated into the infrastructure and carries out the results of dynamic simulations referring to real operating data of the system and vehicles. The results highlight the performance of the WESS in terms of energy and power exchange, also discussing economic aspects.

Electrified railway systems are stimulating worldwide a growing interest in innovative models, technologies and operating measures to increase energy efficiency and sustainable development, while satisfying customer requirements. Railway System Operators (RSOs) are widely studying how technologically renewing infrastructures and vehicles or applying eco-driving techniques. Any measure applied to railway systems impacts also on the primary grid, which supplies the system in terms of power and energy. Modes of impact do not depend only on the type of the measure, but also on the technological characteristics of the railway system and its modalities of operating. Aiming at verifying the interaction between a real metro system and its primary distribution grid, this paper proposes a methodology to model the interaction between the systems in terms of power flow exchanges. The model is used to verify how eco-driving techniques applied on the railway system can affect the main state variables of the primary grid, modifying the operating values of the instantaneous power and net energy. In this paper, primary grid, traction substations and railway system are modelled according to real data. The observed case study is the line 1 metro system operating in the city of Naples. Numerical simulations are carried out by means of a two-step procedure: 1) the OpenTrack software is used to determine the power requirements of the railway system as a function of the imposed operating constraints; 2) the power flow approach assesses the operating state of the distribution grid.

Water availability is a major limiting factor in plant productivity and plays a key role in plant species distribution over a given area. New technologies, such as terahertz quantum cascade lasers (THz-QCLs) have proven to be non-invasive, effective, and accurate tools for measuring and monitoring leaf water content. This study explores the feasibility of using an advanced THz-QCL device for measuring the absolute leaf water content in Corylus avellana L., Laurus nobilis L., Ostrya carpinifolia Scop., Quercus ilex L., Quercus suber L., and Vitis vinifera L. (cv. Sangiovese). A recently proposed, simple spectroscopic technique was used, consisting in determining the transmission of the THz light beam through the leaf combined with a photographic measurement of the leaf area. A significant correlation was found between the product of the leaf optical depth (&tau, ) and the leaf surface area (LA) with the leaf water mass (Mw) for all the studied species (Pearson&rsquo, s r test, p &le, 0.05). In all cases, the best fit regression line, in the graphs of &tau, LA as a function of Mw, displayed R2 values always greater than 0.85. The method proposed can be combined with water stress indices of plants in order to gain a better understanding of the leaf water management processes or to indirectly monitor the kinetics of leaf invasion by pathogenic bacteria, possibly leading to the development of specific models to study and fight them.