Politecnio die Bari - Catalogo di prodotti della Ricerca
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Synthesis, oxidation and unusual coordination chemistry of the diphosphete complex [(Cp′′′Co)2(μ,η4:4-(CH3CP)2)]
No full textNotwithstanding four decades of active research, very rare examples of diphosphabutadiene complexes arising from dimerisation of the phosphaalkyne CH3-C P have been reported. Herein, we show that methyl phosphaalkyne dimerises in the coordination sphere of Cp′′′Co fragments to yield the unprecedented diphosphete complex [Cp′′′Co(η4-P2C2Me2)] (1) and the triple-decker complex [{Cp′′′Co}2(μ,η4:η4-P2C2Me2)] (2). Compound 2 can be oxidised with Ag[Al{OC(CF3)3}4] (Ag[TEF]) to give [{Cp′′′Co}2(μ,η4:η4-P2C2Me2)][TEF] (3). Additionally, it shows an unusual coordination behaviour towards copper halides and [W(CO)4(nbd)] (nbd = norbornadiene). Its reaction with CuCl leads to the formation of the 1D polymer [{Cp′′′Co}2(μ,η4:η2:η1:η1-P2C2Me2){Cu(μ-Cl)}2]n (6) while its reaction with CuBr, CuI and [W(CO)4(nbd)] results in the metallacyclic compounds [(Cp′′′Co){μ3,η4:η1:η1-P2C2Me2}(CH3CN){Cu(μ-X)}2]2 (X = Br (7a), I (7b)) and [Cp′′′Co{μ3,η4:η1:η1-P2C2Me2}{W(CO)4}]3 (8). In 6, an isomerisation of the diphosphete ring to a diphosphacyclopentadienyl ring occurs. In 7 and 8, the loss of Cp′′′Co moieties from the former compound 2 is observed. The formation of 1,3-diphosphete rings in 1 and 2 instead of the more thermodynamically favoured 1,2-diphosphete rings are explained by DFT computations
Hydrothermal Surface Treatment of Mg AZ31 SPF Alloy: Immune Cell Biocompatibility and Antibacterial Potential for Orthopaedic Applications
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The SYNERISE dataset: An E-Commerce Dataset for Sequential Recommendation, Universal Behavior Modeling and Deep Relational Learning
No full textOptimization of multi-satellite constellations for GNSS spectrum monitoring applications via AOA-TDOA receivers in LEO
No full textSatellite-based platforms in Low Earth orbit (LEO) constellations equipped with advanced sensors can be a solution to detect and locate non-cooperative emitters, such as ground-based interferences. This article deals with the fundamental question on the distribution of the satellites within a constellation in order to improve the precision of the location estimation and addresses the problem of the spatial optimization of a cluster of satellites in LEO which are able to perform both Angle of Arrival (AOA) and Time Difference of Arrival (TDOA) measurements. The study provides a step-by-step theoretical methodology to build the optimization problem on the Position Dilution of Precision (PDOP) taking into account the orbital kinematics of the satellites, the measurement errors on AOA-TDOA receivers, the constraints due to the Line of Sight (LOS), and minimum Signal-to-Noise Ratio (SNR) values in order to guarantee certain probabilities of detection and false alarms. An exemplary application of the optimization approach is presented for GNSS (Global Navigation Satellite System) spectrum monitoring in L1/E1 band through a system composed of two satellites in LEO considering a conservative constrained scenario not too far from the Nadir direction. The results obtained reveal emerging patterns of symmetry and anti-symmetry in the angles related to the optimal deployment of the satellite constellation, such as the right ascension of the ascending node, the true anomaly, and the spacing angle between the satellites with respect to the emitter position
Time-resolved analysis of carbon monoxide emissions from vehicles using a quartz-enhanced photoacoustic sensor
No full textLow-cost sensors networks hold the promise of dense spatial mapping over wide areas, through a combination of its price point and transportability, with a fine spatial reconstruction of the pollutants. Their reliability and the limited performance, particularly at finer temporal resolutions, represents the other side of coin. These shortcomings in dynamic environments pose serious challenges for their use in exposure studies and mobile applications. A recommendation for careful calibration, strategic experimental design, and an emphasis on high temporal resolution use cases are essential for guiding future technological development without losing key features, such as portability and compactness. In this work, we used a Quartz-Enhanced Photoacoustic Spectroscopy (QEPAS)-based sensor for sequentially measuring carbon monoxide (CO), nitrous oxide (N2O), and water vapor emissions near vehicle exhaust pipes. With detection limits of 150 ppb for N2O and 91 ppb for CO, this sensor allows for precise emission measurements. Moreover, the 300 ms temporal resolution enables real-time tracking of emission variations with a detailed temporal analysis. Field tests at the University of Bari Campus parking area confirmed the sensor capability to capture CO concentration fluctuations from both idling and moving vehicles
A Tiny Deep Learning Model for Sleep Apnea Detection Based on ECG Signals
No full textSleep apnea is a prevalent and often underdiagnosed sleep disorder characterized by repeated interruptions in breathing during sleep, which can lead to serious health complications such as hypertension, cardiovascular disease, and daytime fatigue. Traditional methods for diagnosing sleep apnea rely on polysomnography, which is expensive, time-consuming, and requires a clinical setting. To address these limitations, recent approaches have explored automated sleep apnea detection using electrocardiogram (ECG) signals. However, existing approaches rely on ECG feature extraction, such as RR intervals, before apnea event classification. This paper presents a Tiny Deep Learning (TinyDL) approach for detecting sleep apnea on resource-constrained embedded devices by using raw ECG signals. Unlike previous studies that rely on ECG signal preprocessing to extract features such as RR intervals before classification, we propose a lightweight convolutional neural network (CNN) that directly processes raw ECG data, eliminating the need for feature extraction. The model is trained on the PhysioNET Apnea-ECG dataset and optimized for deployment on an STM32 Nucleo-F401RE board. Model quantization is employed to reduce memory footprint and computational complexity while maintaining classification accuracy. Experimental results demonstrate the feasibility of deploying DL-based sleep apnea detection on low-power embedded systems, achieving accuracy comparable with that of TinyML models requiring feature extraction
User-Centered Perspectives in Prefabricated Timber Buildings: A Scoping Review
No full textThe construction of prefabricated timber buildings is a topic of growing interest, although research has primarily focused on technological aspects, while the users’ perspective remains underexplored. Accordingly, this paper aims to map the existing literature on prefabricated wooden buildings from a user-centered perspective, considering the whole-building scale. A systematic literature search of publications between 2010 and 2025 was conducted following PRISMA guidelines, identifying relevant studies. A bibliometric analysis was then performed to map key research themes, which were further examined through a scoping review. Four main themes emerged, i.e., indoor comfort, indoor air quality, sustainability and energy efficiency, and building architectural design. The findings highlight numerous aspects that should be considered in prefabricated timber buildings design, including thermal, vibrational and acoustic comfort, air pollutant and ventilation control, user behavior in relation to energy use, and spatial design based on users’ needs. However, the limited number of existing studies makes comprehensive evaluation difficult. Furthermore, the results emphasize the need for multidisciplinary approaches to adequately integrate user experience into the design of these buildings
First International Workshop on Data Quality-Aware Multimodal Recommendation (DaQuaMRec)
No full textThe Effect of Varying Abutment Heights on Stress Distribution in Different Bone Densities: A Finite Element Analysis Study
No full textThe biomechanical performance of dental implants is affected by both abutment height and bone quality, which influence stress distribution around the implant and the preservation of surrounding bone. This study used three-dimensional finite element analysis (FEA) to assess the combined effects of these factors. Two implants with abutment heights of 3 mm and 6 mm were modeled and placed in mandibular bone blocks representing class II and class IV bone, according to Lekholm and Zarb's classification. A static load of 150 N, inclined at 6 degrees buccolingually, was applied during the analysis. The simulation results showed that increasing the abutment height raises stress on the implant, leading to greater stress transfer to the peri-implant bone. The von Mises stress levels were higher in the crestal cortical bone of the class IV model with a 6 mm abutment (126 MPa). Notably, peak stresses exceeding 300 MPa were localized at the implant-abutment connection. These findings suggest that abutment height is a critical factor that negatively affects the biomechanical response, especially in low-density bone, although longer abutments offer biological benefits. This highlights the importance of minimizing the crown-to-implant ratio to reduce overload, preserve bone, and prevent mechanical failure complications