1,720,993 research outputs found
Applicazione di metodologie termografiche alla diagnosi e propensione al degrado di edifici storici in Sardegna
No full textIl cinema come strumento pedagogico: percorsi di educazione e valutazione degli atteggiamenti prosociali nella scuola secondaria di II grado
No full textIl cinema rappresenta uno strumento pedagogico efficace grazie alla sua capacità di attrarre, coinvolgere e trasmettere concetti in modo immediato.In ambito educativo, tra i tanti argomenti, può essere utilizzato per affrontare temi complessi come diversità, disabilità ed esclusione, stimolando lariflessione critica e l'empatia degli studenti attraverso la loro identificazione con i personaggi. A tal fine, il presente contributo intende illustrare i risultatidi uno studio esplorativo che ha coinvolto 287 insegnanti di scuola secondaria di II grado iscritti al corso di Specializzazione per le Attività di Sostegnopresso l’Università degli Studi di Firenze nell'anno accademico 2022/2023. In particolare, si concentra su un'analisi a metodi misti di attività collaborativeriguardanti la progettazione di percorsi educativi volti a promuovere atteggiamenti prosociali degli studenti attraverso i film. I temi principali, gli approccididattici e le strategie di valutazione emersi dall'analisi offrono preziosi spunti su come utilizzare il cinema in una prospettiva media educativa, favorendola prosocialità e l'inclusione nei contesti dell’istruzione secondaria superiore
A 2.4 GHz LoRa-Based Protocol for Communication and Energy Harvesting on Industry Machines
Full text linkThe fourth industrial revolution is paving the way for Industrial Internet of Things applications where large number of wireless nodes, equipped with sensors and actuators, monitor the production cycle of industrial goods. This paper proposes and analyses LoRaIN, a network architecture and MAC-layer protocol thought for on-demand monitoring of industrial machines. Our proprietary system is an energy-efficient, reliable and scalable solution, where the protocol is built on top of LoRa at 2.4 GHz. Indeed, the low-power characteristics of LoRa allow to reduce energy consumption, while Wireless Power Transfer is used to recharge batteries, avoiding periodic battery replacement. High reliability is obtained through the joint use of Frequency and Time Division Multiple Access. A dynamic LoRaIN scheduler manages the communication and recharging phases depending on the tasks assigned to the nodes, as well as the number of monitoring devices. Performance is measured in terms of network throughput, energy consumption and latency. Results demonstrate that the proposed solution is suitable for monitoring applications of industry machines
OCDMA: a MAC Protocol for Industrial Intra-machine TeraHertz Network
Full text linkThis paper considers an industrial machine, where wireless sensor nodes (denoted as tags or nodes) support control applications. This scenario poses very challenging communication requirements: hundreds of tags per cubic meter can provide an overall offered throughput of tens of Gbit/s; at the same time, control applications require a latency of less than 0.1 ms. To fulfill them, this work proposes an Orthogonal Chirp Division Multiple Access (OCDMA) scheme to be used in the TeraHertz (THz) frequency band. With THz communications, even at short distances, propagation delays can be of the same order of magnitude as the packet transmission time. This requires proper consideration of such delays in the protocol design and performance evaluation. This paper mathematically derives network throughput and latency of the proposed protocol, comparing it to benchmarks; two scenarios are considered, where tags are in fixed positions or move. Results show that OCDMA outperforms the two benchmark protocols, Aloha and Polling, for static and crowded networks, and the performance is compatible with the communication requirements of industrial control applications
Characterization of Orthogonal Chirp Division Multiplexing and Performance Evaluation at THz Frequencies in the Presence of Phase Noise
Full text linkDue to its superior performance, Orthogonal Chirp Division Multiplexing (OCDM) has recently gained attention as a potential replacement for Orthogonal Frequency Division Multiplexing (OFDM) in beyond-5G systems. In this paper, we provide an analytical characterization of OCDM signals, elucidating the theoretical principles that enable their numerical generation through the Inverse Discrete Fresnel Transform (IDFnT), despite the presence of severe frequency-domain aliasing that substantially distorts the signal at the transmitter output. Furthermore, in light of the proposed utilization of the THz band in beyond-5G systems, we investigate the performance of OCDM in this frequency range in the presence of thermal, molecular, and phase noise. To model the latter, which is expected to be a significant challenge at THz frequencies, we take as a reference an actual Phase Locked Loop (PLL) oscillator operating at 237.7 GHz. The numerical results reveal the achievable performance of OCDM as a function of several key factors, including the modulation order, the bandwidth, the number of chirps constituting the signal, the oscillator parameters, the channel model, and the use of techniques aimed at mitigating the impact of phase noise. The findings are compared with those of OFDM, which is regarded as a benchmark due to its adoption in 4G and 5G systems, and demonstrate the superior performance of OCDM also in the presence of significant phase noise
Predisposing factors, clinical and microbiological aspects of bacterial keratitis: a clinical study.
No full textOn the Support of the 2.4 GHz Band in the LoRaWAN Standard
Full text linkThe introduction of LoRa chipsets operating in the 2.4 GHz band paves the way to unprecedented performance enhancements compared to their sub GHz counterparts, attributed to factors such as the absence of duty cycle constraints and higher data rates. Despite its potential benefits for Internet of Thing (IoT) applications, the LoRa Alliance has not yet proposed the integration of this new frequency spectrum into the LoRaWAN standard. Addressing this gap, this article proposes a roadmap for the evolution of the LoRaWAN standard, outlining three stages for seamless integration of the 2.4 GHz LoRa version. These stages are sequenced based on implementation complexity, starting from the current LoRaWAN standard (Stage 0), moving to the coexistence of two separate LoRaWAN networks (Stage 1), and ending with a single LoRaWAN network capable of supporting both sub GHz and 2.4 GHz bands (Stage 2). Additionally, the document enumerates all possible implementation options for each stage and outlines the main modifications required in the documents of the LoRaWAN standard. Through LoRaWAN-compliant simulation results, we demonstrate the performance advantages of the proposed multi-band approach over the existing LoRaWAN standard for the first stage of the suggested roadmap. Finally, the article discusses the challenges associated with the proposed roadmap and identifies corresponding research gaps to be addressed in the future
Applicazione di metodologie geofisiche per la caratterizzazione delle rocce ornamentali. 28° CarraraMarmotec, Carrara 30 Maggio-2 Giugno 2007
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