Vibration Control of Innovative Lightweight Thermoplastic Composite Material via Smart Actuators for Aerospace Applications

Piezoelectric actuators and sensors can be incorporated into aerospace structures to suppress unwanted flexible oscillations. These devices need to interact with various passive structures, including innovative materials such as thermoplastic composites, which offer several advantages over traditional options. This study explores the application of a piezoelectric-based vibration control system on a lightweight carbon-reinforced thermoplastic material. Numerical and experimental investigations are conducted to assess the mechanical properties and damping behavior of the composite. As a case study, an equivalent orthotropic shell laminate is developed to facilitate finite element modeling of two composite solar panel structures equipped to a spacecraft. Moreover, an electro-mechanical formulation is implemented to integrate smart actuators and sensors onto the composite hosting structure. Finally, the efficiency of the active vibration control system is assessed when significant vibration perturbations are caused on the panels by rigid–flexible dynamics coupling during agile attitude maneuvers. The results demonstrate the damping factor of the material can be noticeably improved, making the proposed system a promising technological solution for further aerospace applications. © 2023 by the authors

Mass testing of the JUNO experiment 20-inch PMTs readout electronics

The Jiangmen Underground Neutrino Observatory (JUNO) is a multi-purpose, large size, liquid scintillator experiment under construction in China. JUNO will perform leading measurements detecting neutrinos from different sources (reactor, terrestrial and astrophysical neutrinos) covering a wide energy range (from 200 keV to several GeV). This paper focuses on the design and development of a test protocol for the 20-inch PMT underwater readout electronics, performed in parallel to the mass production line. In a time period of about ten months, a total number of 6950 electronic boards were tested with an acceptance yield of 99.1%

Implementation and performances of the IPbus protocol for the JUNO Large-PMT readout electronics

The Jiangmen Underground Neutrino Observatory (JUNO) is a large neutrino detector currently under construction in China. Thanks to the tight requirements on its optical and radio-purity properties, it will be able to perform leading measurements detecting terrestrial and astrophysical neutrinos in a wide energy range from tens of keV to hundreds of MeV. A key requirement for the success of the experiment is an unprecedented 3% energy resolution, guaranteed by its large active mass (20 kton) and the use of more than 20,000 20-inch photo-multiplier tubes (PMTs) acquired by high-speed, high-resolution sampling electronics located very close to the PMTs. As the Front-End and Read-Out electronics is expected to continuously run underwater for 30 years, a reliable readout acquisition system capable of handling the timestamped data stream coming from the Large-PMTs and permitting to simultaneously monitor and operate remotely the inaccessible electronics had to be developed. In this contribution, the firmware and hardware implementation of the IPbus based readout protocol will be presented, together with the performances measured on final modules during the mass production of the electronics

Validation and integration tests of the JUNO 20-inch PMTs readout electronics

The Jiangmen Underground Neutrino Observatory (JUNO) is a large neutrino detector currently under construction in China. JUNO will be able to study the neutrino mass ordering and to perform leading measurements detecting terrestrial and astrophysical neutrinos in a wide energy range, spanning from 200 keV to several GeV. Given the ambitious physics goals of JUNO, the electronic system has to meet specific tight requirements, and a thorough characterization is required. The present paper describes the tests performed on the readout modules to measure their performances.Comment: 20 pages, 13 figure

Real-time Monitoring for the Next Core-Collapse Supernova in JUNO

Core-collapse supernova (CCSN) is one of the most energetic astrophysical events in the Universe. The early and prompt detection of neutrinos before (pre-SN) and during the SN burst is a unique opportunity to realize the multi-messenger observation of the CCSN events. In this work, we describe the monitoring concept and present the sensitivity of the system to the pre-SN and SN neutrinos at the Jiangmen Underground Neutrino Observatory (JUNO), which is a 20 kton liquid scintillator detector under construction in South China. The real-time monitoring system is designed with both the prompt monitors on the electronic board and online monitors at the data acquisition stage, in order to ensure both the alert speed and alert coverage of progenitor stars. By assuming a false alert rate of 1 per year, this monitoring system can be sensitive to the pre-SN neutrinos up to the distance of about 1.6 (0.9) kpc and SN neutrinos up to about 370 (360) kpc for a progenitor mass of 30$M_{\odot}$ for the case of normal (inverted) mass ordering. The pointing ability of the CCSN is evaluated by using the accumulated event anisotropy of the inverse beta decay interactions from pre-SN or SN neutrinos, which, along with the early alert, can play important roles for the followup multi-messenger observations of the next Galactic or nearby extragalactic CCSN.Comment: 24 pages, 9 figure

Behavioral effects induced by organic insecticides can be exploited for a sustainable control of the Orange Spiny Whitefly Aleurocanthus spiniferus

The Orange Spiny Whitefly (OSW) Aleurocanthus spiniferus (Hemiptera: Aleyrodidae) represents a new serious threat to Citrus spp., grapevine and ornamental plants in the whole Mediterranean area. Such threat urgently calls for the development of a sustainable control strategy, including insecticides compatible with biological control, and applicable also in organic citrus farming that represent an essential part of Mediterranean agricultural economy. Therefore, we evaluated the toxicity and the effects on host searching, oviposition, and probing and feeding behavior exerted on OSW by organic insecticides supposed to have limited side effects on environment and ecosystem services, i.e. sweet orange essential oil (EO), extract of Clitoria ternatea (CT), mineral oil, pyrethrin and azadirachtin. Despite none of the compounds caused a significant mortality of any of the OSW instars, we observed interesting effects on whitefly behavior: (i) EO and pyrethrin showed a relevant repellent effect, with impairment of both adults landing and oviposition on treated plants; (ii) CT and pyrethrin strongly affected probing behavior. Here, in the light of our findings, we discuss possible OSW sustainable control strategies and further research perspectives

Structural design of booms for the solar sail of Helianthus sailcraft

Solar sail is a promising propulsion concept that exploits solar pressure to navigate in space without the use of propellants, therefore enabling missions otherwise not attainable by traditional propulsion (i.e. electric or chemical propulsion). For instance, a synchronous solar sail with the Earth-Moon barycenter to be used as a long warning time of solar storms caused by Coronal Mass Ejections is the main objective of the Helianthus project, funded by the Italian Space Agency. This paper is aimed specifically at the presentation and description of the design of the structural subsystem for the solar sail of the Helianthus project. This subsystem is composed of four deployable ultralight booms, which deploy and keep the sail-membrane in tension. The booms have to withstand the axial load, generated by the tensioned membrane, which must be smaller than the critical load at buckling. At the same time, the booms need to have sufficient stiffness to prevent a large out-of-plane displacement of the membrane leading to reduction of the thrust. First, the geometry and the dimensions of the boom cross-section to optimize the stiffness is determined. Then, a structural numerical analysis on a full-scale model of a square solar sail (40 m x 40 m) with four supporting booms is performed. For such configuration, the sail tension is simulated in order to determine the axial load acting on the tip of each boom and the displacements due to the solar radiation pressure are evaluated. Simulations are carried out by finite element method using the software ABAQUS. Results are presented at both system and individual components level

The impact of UEFA Euro 2020 football championship on Takotsubo Syndrome: Results of a multicenter national registry

ObjectivesThe UEFA 2020 European Football Championship held in multiple cities across Europe from June 11 to July 11, 2021, was won by Italy, providing an opportunity to examine the relationship between emotional stress and the incidence of acute cardiovascular events (ACE). Methods and resultsCardiovascular hospitalizations in the Cardiac Care Units of 49 hospital networks in Italy were assessed by emergency physicians during the UEFA Euro 2020 Football Championship. We compared the events that occurred during matches involving Italy with events that occurred during the remaining days of the championship as the control period. ACE was assessed in 1,235 patients. ACE during the UEFA Euro 2020 Football Championship semifinal and final, the most stressful matches ended with penalties and victory of the Italian team, were assessed. A significant increase in the incidence of Takotsubo Syndrome (TTS) by a factor of 11.41 (1.6-495.1, P < 0.003), as compared with the control period, was demonstrated during the semifinal and final, whereas no differences were found in the incidence of ACS [IRR 0.93(0.74-1.18), P = 0.57]. No differences in the incidence of ACS [IRR 0.98 (0.87-1.11; P = 0.80)] or TTS [IRR 1.66(0.80-3.4), P = 0.14] were found in the entire period including all matches of the UEFA Euro 2020 compared to the control period. ConclusionsThe data of this national registry demonstrated an association between the semifinal and final of UEFA Euro 2020 and TTS suggesting that it can be triggered by also positive emotions such as the victory in the European Football Championship finals

Data_Sheet_1_The impact of UEFA Euro 2020 football championship on Takotsubo Syndrome: Results of a multicenter national registry.PDF

ObjectivesThe UEFA 2020 European Football Championship held in multiple cities across Europe from June 11 to July 11, 2021, was won by Italy, providing an opportunity to examine the relationship between emotional stress and the incidence of acute cardiovascular events (ACE).Methods and resultsCardiovascular hospitalizations in the Cardiac Care Units of 49 hospital networks in Italy were assessed by emergency physicians during the UEFA Euro 2020 Football Championship. We compared the events that occurred during matches involving Italy with events that occurred during the remaining days of the championship as the control period. ACE was assessed in 1,235 patients. ACE during the UEFA Euro 2020 Football Championship semifinal and final, the most stressful matches ended with penalties and victory of the Italian team, were assessed. A significant increase in the incidence of Takotsubo Syndrome (TTS) by a factor of 11.41 (1.6–495.1, P ConclusionsThe data of this national registry demonstrated an association between the semifinal and final of UEFA Euro 2020 and TTS suggesting that it can be triggered by also positive emotions such as the victory in the European Football Championship finals.</p