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An Econometric Analysis of the Energy-Saving Performance of the Italian Plastic Manufacturing Sector
No full textIn a scenario characterised by mitigation concerns and calls for greater resilience in the energy sector, energy audits (EAs) emerge as an essential mean for enhancing end-use energy consumption awareness and efficiency. Such a tool allows us to assess the different energy carriers consumed in a productive sector, offering insight into existing energy efficiency improvement opportunities. This opens avenues for research to devise an econometrics-based methodology that encapsulate production sites and their environmental essentials. This paper contributes to the literature by exploiting the EAs received by the Italian National agency for New technologies, Energy, and Sustainable Economic Development (ENEA) in 2019 from the Italian plastics manufacturing sector, matched with Italian firm-based data extracted from the Analisi Informatizzata delle Aziende Italiane (Italian company information and business intelligence) (AIDA) database. In particular, we investigate how the implementation of energy efficiency measures (EEMs) is influenced by a set of contextual factors, as well as features relating to the companies and EEMs themselves. The empirical investigation focuses on the EAs submitted to ENEA in 2019, which was strategically chosen due to its unique data availability and adequacy for extensive analysis. The selection of 2019 is justified as it constitutes the second mandatory reporting period for energy audits, in contrast to the 2022 data, which are currently undergoing detailed refinement. In line with the literature, the adopted empirical approach involves the use of both the OLS and logistic regression models. Empirical results confirm the relevance of economic and financial factors in guiding the decisions surrounding the sector’s energy performance, alongside the analogous influence of the technical characteristics of the measures themselves and of the firms’ strategies. In particular, the OLS model with no fixed effects shows that a one-percent variation in investments is associated with an increase in savings performance equal to 0.63%. As for the OLS model, including fixed effects, the elasticity among the two variables concerned reaches 0.87%, while in the logistic regression, if the investment carried out by the production sites increases, the expected percentage change in the probability that the energy-saving performance is above its average is about 187.77%. Contextual factors that prove to be equally influential include the incentive mechanism considered and the traits of the geographical area in which the companies are located. Relevant policy implications derived from this analysis include the importance of reducing informational barriers about EEMs and increasing technical assistance, which can be crucial for identifying and implementing effective energy solutions
The Role of Emergent Technologies in the Dynamic and Kinematic Assessment of Human Movement in Sport and Clinical Applications
No full textPhysical activity analysis assessment has been a concern throughout human history. The intersection of technological growth with sports has given rise to a burgeoning field known as sports engineering. In the 19th century, the advent of chrono-photography and pioneering marked the inception of sports performance analysis. In recent years, the noticeable developments achieved in wearable low-power electronics with wireless high interconnection capability, as a part of modern technologies, have aided us in studying sports parameters such as motor behavior, biomechanics, equipment design, and materials science, playing an essential role in the understanding of sports dynamics. This study aims to review over 250 published articles since 2018, focusing on utilizing and validating these emergent technologies in sports and clinical aspects. It is predicted that one of the next steps in sports technology and engineering development will be using algorithms based on artificial intelligence to analyze the measurements obtained by multi-sensor systems (sensor fusion) to monitor biometric and physiological parameters in performance analysis and health assessments
Innovative Method for Reliability Assessment of Power Systems: From Components Modeling to Key Indicators Evaluation
Get PDFPower systems comprise different electrical, electronic, electromechanical and electrochemical components. Adequacy, security, resilience and reliability represent essential requirements for grids functioning mode. The evaluation of such aspects can constitute a delicate task in the presence of heterogeneous components. Focusing on reliability assessment, several Reliability Prediction Models are available. They are suitably applied according to the type of component under evaluation. The lack of homogeneity of these models forbids the comparison of performance and identification of unreliable systems and grid section. This paper aims to face the mentioned issue proposing a unique reliability assessment methodology able to characterize different equipment connected to radial/meshed/ring grids and subjected to different stressing and ageing factors. It is customized for electrical lines, transformers, circuit breakers, converters and renewables plants. Component and systemic key indices are calculated. Furthermore, a novel “load feeding reliability“ indicator is evaluated for providing information about the supply reliability of a specific load. This index is meaningful for the identification of unreliable grids, microgrids and systems. Such an approach can contribute to improve power systems design, planning and control. The proposed method is integrated in a software application implemented for grid reliability assessment. The obtained results are reported for an urban grid including an underground transportation area
Analysis of the Effects of Overcharging Lithium Ion Cells with Graphite Anode: Efficiency of Protection Devices Integrated into the Cells
No full textLithium ion batteries are currently the main technology for storing energy in electric vehicles thanks to their high power density and energy density. Among the many challenges, safety related aspects must be faced. The thermal runaway caused by overcharge is one of the main weak points to be addressed to ensure a proper level of safety, necessary for the diffusion of this technology.Nowadays, many cells have integrated protection devices that reduce the risk of thermal runaway triggered by overcharging. In this study, the efficiency of devices used to prevent the thermal runaway, caused by overcharging cylindrical 18650 lithium-ion cells with graphite anode, is evaluated. Experimental tests were carried out at different ambient temperatures and overcharge currents.In all the cases the intervention of the Current Interrupt Device avoids the thermal runaway occurrence, preventing the intervention of the others protection devices such as the Positive Temperature Coefficient device and the safety vent
Fast remote spectral discrimination through ghost spectrometry
No full textAssessing the presence of chemical, biological, radiological, and nuclear threats is a crucial task which is usually dealt with in spectroscopic measurements by analyzing the presence of spectral features in a measured absorption profile. The use of quantum ghost spectroscopy opens up the enticing perspective to perform these measurements remotely without compromising the measurement accuracy. However, in order to have the necessary signal-to-noise ratio, long acquisition times are typically required, hence subtracting from the benefits provided by remote sensing. In many instances, though, reconstructing the full spectral lineshape of an object is not needed and the interest lies in ascertaining the presence of a spectrally absorbing object. Here, we present an experimental investigation on the employ of the hypothesis testing framework to obtain a fast and accurate discrimination, carried out by ghost spectrometry. We discuss the experimental results obtained with different samples and complement them with simulations to explore the most common scenarios
Quantum process matrices as images: New tools to design novel denoising methods
No full textInferring a process matrix characterizing a quantum channel from experimental measurements is a key issue of quantum information. Noise affecting the measured counts could bring to matrices different from the expected ones and optimization methods usually employed, i.e. the maximum likelihood estimation (MLE), are characterized by several drawbacks. Lowering the noise could be necessary to increase the experimental resources, e.g. time for each measurement. In this paper, an alternative procedure, based on suitable Neural Networks, has been implemented and optimized to obtain a denoised process matrix and this approach has been tested with a specific quantum channel, i.e. a Control Phase. This promising method relies on the analogy that can be established between the elements of a process matrix and the pixels of an image
Crystal growth and Hall effect of the non-centrosymmetric superconductor α-BiPd and the topological superconductor β-Bi2Pd
No full textDue to the rarity of triplet pairing, topological superconductors (SCs) have primarily been realized experimentally in manufactured topological phases, such as heterostructures, where the proximity effect causes triplet pairing with traditional s-wave SCs. Recently, there has been a lot of interest in investigating novel quantum materials with spin-triplet pairs in order to develop Majorana physics and creating quantum computers. Bi-based superconductors are speculated to hold promise for realizing spin-triplet pairing due to its large spin orbit coupling. In this work, we present the growth of α-BiPd and β-Bi2Pd single crystals using the optical floating zone technique and their characterization. The single crystals of α-BiPd and β-Bi2Pd are found to crystallize in monoclinic and tetragonal crystalline system with space group P21 and I4/mmm, respectively. The composition and microstructure of the grown crystals were analyzed with a scanning electron microscope, through energy dispersive spectroscopy (EDS) and electron backscattered diffraction (EBSD) analysis. The superconducting behavior and Hall effect of both α-BiPd and β-Bi2Pd single crystals have been investigated through resistivity measurements
Experimental Analysis of Steam Generator Tube Rupture in CIRCE Facility for MYRRHA Configuration
No full textOne of the main safety issues of Generation IV (Gen IV) heavy liquid-metal fast reactors is the postulated steam generator tube rupture (SGTR) accident. This event is characterized by primary and secondary coolant interaction, referred to in the literature as a coolant-coolant interaction event having a nonzero probability to occur. This accident scenario could affect the safety of a pool-type reactor, as a consequence of water secondary coolant flashing into the primary coolant liquid metal. The SGTR event needs to be experimentally characterized to evaluate the pressure waves effect, tube rupture propagation (domino effect), oxide precipitation and slug and plug formation, cover gas pressurization of the reactor, and steam flow paths through the pool and eventually the core, entailing the risk of positive reactivity insertion (due to positive local void coefficient). The design phase of the Gen IV MYRRHA plant has dealt with postulated SGTR safety issues in the framework of the MAXSIMA project, which is supported by the European Commission. A relevant contribution to this research activity was provided by the Italian Agency for New Technologies, Energy and Sustainable Economic Development Research Center Brasimone, where a new test section has been designed, assembled, instrumented, and implemented in the large-scale integral-effects pool facility CIRCE for investigating the SGTR event in a relevant configuration for the heat removal system of MYRRHA. This research reactor is not oriented to steam production for running a turbogenerator (no electric production), thus the heat removal system is referred to as the primary heat exchanger (PHX) and not as a steam generator. Four full-scale portions (four bundles of 31 tubes) of the MYRRHA PHX were adopted to carry out four independent SGTR experiments. Water flowed upward in the central tube of the bundle and two rupture positions were investigated at the lower and upper levels, named the bottom and middle scenarios, respectively. After the rupture, water was injected at 16 bar and 200°C into lead bismuth eutectic alloy at 350°C. The experimental results showed a remarkable repeatability and were presented in terms of (1) CIRCE vessel pressurization up to 2.7 and 4 bar absolute for the middle and bottom scenarios, respectively; (2) vapor flow paths through the bundle and its cooling effect up to 120°C and 140°C for the middle and bottom tests, respectively; and (3) strain measurements on tubes and bundle shells up to 2800 μm/m. The integrity of the tubes surrounding the ruptured one and the effectiveness of implemented safety device (rupture disks) pressure relief were significant engineering feedback for MYRRHA designers. The acquired high-quality data also constitute a database increase for future code verification and validation and possible new model development. The performed experimental analysis provided the awareness that a suitable design of a depressurization system (e.g., rupture disks) could allow for addressing postulated SGTR events in the MYRRHA configuration with confidence and safety
Fused Filament Fabrication of Polyethylene/Graphene Composites for In-Space Manufacturing
Get PDFGraphene-based composite materials are highly sought after for space applications due to their ability to encompass various properties, such as electrical conductivity, thermal resistance, and radiation shielding. This versatility allows for the creation of multifunctional components that can serve various purposes in space. Three-dimensional (3D) printing of composite materials in space offers a versatile and efficient means of manufacturing components, tools, and structures that are tailored to the unique challenges and requirements of space missions. In this work, we aim to develop 3D-printed composites made of medium-density polyethylene (MDPE) matrix and exfoliated graphene nanoplatelets (xGnP) as filler, using fused filament fabrication (FFF). Our research focuses on the challenges associated with the FFF process for fabricating MDPE/xGnP materials, particularly by optimizing filament extrusion and assessing the resulting material properties and space environmental compatibility. Firstly, we optimize the extrusion process, and use the MDPE/xGnP filaments to fabricate 3D-printed samples after defining the FFF parameters. We employ differential scanning calorimetry (DSC) to assess the melting properties and crystallization degree of the extruded filaments and 3D-printed samples, providing insights into the relationship between these properties and the characteristics of the initial powders. Electrical and tensile tests are carried out to evaluate the material properties after successfully mitigating challenges, such as warping and inadequate adhesion, to build plates during the printing process. Finally, we subject the 3D-printed composites to outgassing tests under exposure to the AM0 solar spectrum to evaluate their space environmental suitability. The results of this work demonstrate the capability of the FFF-based process to efficiently manufacture components made of MDPE/xGnP composites, providing optimized parameters for their potential in-space fabrication
New PV encapsulants: assessment of change in optical and thermal properties and chemical degradation after UV aging
No full textThis work aims to investigate the change in chemical and physical properties of different polymeric materials, potentially usable for photovoltaic modules encapsulation, caused by UV aging. Three classes of polymeric materials have been examined: ethylene-vinyl-acetate (EVA), thermoplastic polyolefins (TPO) and polyolefin elastomers (POE). EVA is currently the most used encapsulant in the photovoltaic field; TPO and POE are new materials, alternative to EVA, which can allow to overcome some of the reliability problems of photovoltaic modules linked to the degradation of EVA properties. Of each of these three material classes, different commercially available encapsulating polymer films, with different chemical formulations, have been examined. Stressful environmental conditions have been simulated in a climatic chamber and the associated changes in optical, thermal and chemical properties of the different encapsulants have been analysed and compared before and after UV aging. The link between the chemical structure, formulation and degradation of the encapsulants with their lifetime under simulated conditions of UV stress has been investigated by the assessment of the changes in thermal stability, optical transmittance, crystallinity, yellowness index and chemical degradation. This study helps to better understand the causes of the module performance reduction due to the degradation of the encapsulant material and is a guide for the selection of encapsulant films with improved characteristics, for the manufacture of more durable PV modules