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GLRT-Based Techniques for the Reception of Satellite ADS-B Messages
No full textSatellite-based automatic dependent surveillance-broadcast (ADS-B) enables global-scale aircraft tracking, but introduces significant challenges in packet detection due to the severe signal attenuation experienced along the propagation path. This paper investigates detection strategies for satellite ADS-B receivers based on the generalized likelihood ratio test (GLRT), providing a statistically sound alternative to existing heuristic solutions. To enhance robustness against residual frequency offsets, we exploit the modulus of the received samples, which is invariant to phase distortions. Additionally, we extend the observation window beyond the packet preamble to improve detection performance. To reduce the computational cost of an exact GLRT implementation, we explore several alternatives, including an asymptotic approximation of the Rician distribution and a Gaussian model for the observation data. Simulation results show that the proposed schemes achieve reliable detection even at low signal-to-noise ratios, and outperform existing methods by leveraging both the preamble and part of the data payload
Sensitivity analysis in severe accident simulations:A historical perspective
No full textIn recent years, the application of Best Estimate Plus Uncertainty methodologies in the frame of Severe Accidents (SAs) has gained significant momentum. Both researchers and regulatory bodies in the field recognize the importance of quantifying the uncertainties associated with SA codes results as well as sensitivity analysis’ relevance in understanding the variables driving the calculated uncertainty. In this framework, the current work aims to deliver a thorough overview of the historical evolution of the application of sensitivity analysis techniques within the SA domain over the past five decades, detailing their primary focus, geographical context, main techniques and key documents. Highlighting how sensitivity analysis evolved over the years, the paper underscores its critical role within nuclear safety assessments. This review offers both a detailed historical perspective and insights into future directions for research, emphasizing the need for a balance between computational efficiency and model accuracy, and suggesting the integration of machine learning techniques to enhance future analyses
Valutazione d’azienda, intelligenza artificiale e nuove tecnologie, Collana SIDREA di Studi di Valutazione d’Azienda
No full textIl presente volume intende approfondire il rapporto tra valutazione d'azienda e nuove tecnologie.
Il lavoro è suddiviso idealmente in tre sezioni.
Nella prima parte, vengono forniti elementi di contesto di natura economico-aziendale, statistico-informatica e giuridica utili alla comprensione di quanto verrà analizzato nelle parti a seguire. Il riferimento è ai profili concettuali, tecnici, etici e giuridici delle nuove tecnologie.
Nella seconda parte, si analizza l'impatto delle varie tecnologie sull'attività peritale e sul processo di stima. Verranno prese in considerazione l'intelligenza artificiale, la business intelligence, i big data e data analytics, la blockchain e i linguaggi XBRL (eXtensible Business Reporting Language) e ESEF (European Single Electronic Format). L'idea è comprendere in se e come tali nuove tecnologie possono supportare l'attività peritale in termini di qualità e di efficienza.
Nella terza parte, infine, si rifletterà sul valore delle nuove tecnologie intese come oggetto di stima. L'obiettivo è quindi comprendere come valutare tali asset, considerandone l'impatto sui principali driver di valore aziendale, e pertanto quali metodi possono essere applicati tra quelli rientranti nei tre approcci fondamentali, ossia il cost approach, l'income approach e il market approach. In questa sezione si analizzerà il valore dei sistemi di intelligenza artificiale, dei sistemi di business intelligence, dei big data, delle app, dei domini internet, dei software dei sistemi di realtà virtuale/aumentata e del metaverso, dei social media e dei sistemi di cybersecurity
From Waste to Function: Valorization of Collagen-Based Wastes with Natural Deep Eutectic Solvents for Bioadhesive Applications
No full textIn this study, we propose a novel, environmentally, economically, and energetically sustainable approach for the valorization of vegetable-tanned leather waste, aiming at producing biobased adhesives with antibacterial properties and promising water resistance. The treatment of leather scraps was carried out using various Natural Deep Eutectic Solvents (NADES) in mild conditions (1 h, 60 degrees C), i.e., lactic acid:urea in a molar ratio of 2:1, choline chloride:lactic acid in a molar ratio of 1:1, and choline chloride dehydrated oxalic acid in a molar ratio of 1:1. The resulting bioadhesives exhibited excellent binding performances, in particular, on wood substrates. Structural modifications and its thermal behavior of collagen after the treatment were investigated using Fourier Transform Infrared Spectroscopy with Attenuated Total Reflectance (ATR-FTIR), Thermogravimetric Analysis (TGA and TGA/FTIR), Evolved Gas Analysis-Mass Spectrometry (EGA-MS), Pyrolysis-Gas Chromatography-Mass Spectrometry (Py-GC-MS), and proteomic techniques. Overall, this approach highlights a circular and green strategy for upcycling leather industry byproducts into high-performance materials, aligning with current goals in waste minimization and resource efficiency
Headspace solid phase microextraction combined with GC–MS for the analysis of volatile compounds of Calystegia silvatica (Kit.) Griseb. from Algeria
No full textThis study represents the first investigation of the volatile composition of Calystegia silvatica (Convolvulaceae) collected in Algeria, using headspace solid-phase microextraction and gas chromatography/mass spectrometry (HS-SPME-GC/MS). This technique allowed the identification of 44 compounds, constituting 96.9% of the total components. These compounds belong to various chemical classes, including sesquiterpene hydrocarbons (22) and non-terpene derivatives (13), as major groups. Remarkably, the volatile profile of C. silvatica was dominated by sesquiterpenoids (87.1%), particularly sesquiterpene hydrocarbons (83%). Analysis of the aroma profile revealed that the main metabolites were β-caryophyllene, α-gurjunene and germacrene D. Oxygenated sesquiterpenes were present in a smaller proportion (4.1%), mostly represented by palustrol. Other chemical classes, such as monoterpene hydrocarbons, oxygenated monoterpenes, non-terpene derivatives and apocarotenes, have been found in limited quantities. It is worth noting that the data presented in this study have not previously been reported for Calystegia species
Le emergenze agroalimentari
No full textIl capitolo analizza come la preparazione sia diventata centrale nelle politiche agroalimentari europee a iniziare dalla crisi del 2008. Attraverso l’analisi della genesi e del funzionamento del Meccanismo Europeo di Preparazione e Risposta alle Crisi della Sicurezza Alimentare (EFSCM), la ricerca ha portato a individuare due principali modalità di intendere la preparazione: una conservativa, basata sulla digitalizzazione e sull’intensificazione sostenibile della produzione agroalimentare, e l’altra trasformativa, legata a una visione agroecologica degli agrocosistemi che valorizza la diversificazione. Il confronto tra queste diverse visioni della preparazione si riscontra anche nel contesto italiano, dove la digitalizzazione è sostenuta a livello delle politiche pubbliche mentre la prospettiva dell’agroecologia appare ancora debolmente strutturata
Projection-Displacement-Based Query Performance Prediction for Embedded Space of Dense Retrievers
No full textAesthetic Variations: Hegel between Philosophy of Art and Callistics
No full textConsidering both the still ongoing radical uncertainty on the status of aesthetics as well as Hegel’s profound influence on it, a reflection on the reasons, meaning, limits, and alternative options to Hegel’s use of the term “aesthetics” would seem worthwhile. Yet, the extremely copious literature on Hegel’s aesthetics has rarely delved into such issue. While there are several excellent discussions, including some recent and original ones, of Hegel’s understanding of art,4 beauty,5 and aesthetics in general,6 they largely take the received interchangeability of aesthetics and philosophy of art for granted, leaving aside Hegel’s perplexities and variations on the former term,7 both with regard to his philosophical development and to what they might still teach us. This paper briefly addresses such variations, first (1) by laying out and interpreting Hegel’s presentations of his lectures on aesthetics, which can be found at the beginning of both Hotho’s printed version and of the manuscripts of the courses, where the terminological choice is discussed. Secondly, (2) the paper clarifies the double meaning of the term “beauty” with regard to art and hence, thirdly , the reasons for Hegel’s rejection of “callistics” as an alternative name for the discipline (3). In this way, the modest aim of this paper, which constitutes the groundwork for broader future research, is to shed some light on Hegel’s understanding of the discipline he taught under the name of aesthetics or philosophy of art