Politecnio die Bari - Catalogo di prodotti della Ricerca
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A chloride threshold to identify the onset of seawater/saltwater intrusion and a novel categorization of groundwater in coastal aquifers
Get PDFSeawater intrusion is the primary cause of groundwater salinisation in coastal aquifers. However, attributing salinisation solely to seawater intrusion may not always be accurate, given the likely presence of other sources. To understand if salinisation comes from seawater intrusion and its onset is crucial for groundwater management, but there are no definite threshold values for common indicators such as chlorides. Based on 1662 groundwater analyses from five Mediterranean coastal aquifers, the study aimed to distinguish the effects of mixing with present-day seawater from those caused by other sources. The trend analysis of cumulative probability plots of chloride (and total dissolved solids) is a key method for discriminating different groundwater salinisation sources and processes. Results establish that chloride, as a non-reactive tracer, is a more reliable indicator of seawater intrusion than total dissolved solids, a reactive indicator. A chloride concentration threshold of 200 mg/L identifies the seawater intrusion onset. The threshold validation comes from groundwater salinisation facies, as provided by groundwater-type codification. Fresh groundwater (Cl < 200 mg/L) anomalous total dissolved solids highlight the input of non-chloride salts and pollutants, providing caution regarding using total dissolved solids to recognise seawater intrusion. Beyond the threshold (Cl > 200 mg/L), data disclose emergent signals of salinisation sources and water–rock interaction processes overlapping seawater intrusion or the involvement of saline fluids different from present-day seawater. The threshold and a new categorisation of groundwater in coastal aquifers according to salinisation processes provide a benchmark for identifying and managing seawater intrusion in the Mediterranean area
Dynamic Capabilities and Microfoundations to Overcome Barriers to Circular Economy Implementation
Get PDFThe circular economy (CE) aims to reshape production models, aligning them with environmental and social goals. Recent analyses show that global economic systems in 2023 are recycling only 7.3% of their material usage. One reason is the existence of barriers to CE adoption at multiple levels, which in turn require appropriate dynamic capabilities to be overcome. This research explores the connections between barriers and dynamic capabilities, with a focus on their microfoundations, with the aim to develop a comprehensive framework supporting firms to implement CE business models. The study employs a multiple case study on seven Italian companies that successfully undergone the circular transformation across diverse manufacturing industries belonging to Made in Italy, that is, fashion, food, furniture, and paper. The research outlines seven microfoundations linked to the three dynamic capabilities of sensing, seizing, and reconfiguring. These microfoundations allow firms to overcome barriers at the institutional, supply chain, and firm level
Impact of Stochastic and Deterministic Behavior on Natural Ventilation: Thermal Comfort and Indoor Air Quality Performances in a Preschool Case Study
No full textSpectroscopic measurement of volatile organic compounds as biomarkers for human breath analysis
Get PDFI composti BTEX - benzene, toluene, etilbenzene e xileni - sono tra i composti organici volatili (COV) più pericolosi, pertanto il loro rilevamento altamente sensibile e selettivo può fornire informazioni chiave in molte applicazioni, dal monitoraggio ambientale all'analisi dell'espirato. I sensori ottici basati su tecniche di spettroscopia di assorbimento laser (LAS) possono rappresentare una soluzione per il rilevamento di BTEX poiché questi composti mostrano caratteristiche di assorbimento forti e distinte nella regione spettrale 13 - 15 μm. Tra queste tecniche, la spettroscopia fotoacustica a diapason di quarzo (QEPAS) e la spettroscopia termoelastica indotta dalla luce (LITES) rappresentano due tecniche efficaci. L'attività di ricerca svolta durante il mio dottorato di ricerca in Industria 4.0 presso il Politecnico di Bari si è concentrato sullo sviluppo di sensori ottici basati su tecniche QEPAS e LITES per il rilevamento di benzene, mirando la banda di assorbimento target centrata a 14,85 μm utilizzando un Laser a cascata quantica (QCL) non commerciale. I sensori QEPAS e LITES sviluppati hanno mostrato un'eccellente risposta lineare e sono stati ottenuti limiti di rilevamento minimi stimati (MDL), rispettivamente di 13 ppb e 105 ppb, con una costante di tempo del lock-in amplifier di 100 ms.BTEX compounds - benzene, toluene, ethylbenzene, and xylenes - are among the most hazardous Volatile Organic Compounds (VOCs), thus their highly sensitive and selective detection can provide key information in many applications, ranging from environmental monitoring to breath analysis. Optical sensors based on laser absorption spectroscopy (LAS) techniques can represent a viable solution for BTEX detection since these compounds show strong and distinct absorption features in the spectral region 13 - 15 μm. Among these techniques, Quartz-Enhanced Photoacoustic Spectroscopy (QEPAS) and Light-Induced Thermoelastic Spectroscopy (LITES) represent two effective techniques. The research activity carried out during my Ph.D. program in Industry 4.0 at the Polytechnique University of Bari was focused on the development of optical sensors based on QEPAS and LITES techniques for benzene detection, targeting the absorption band centred at 14.85 μm using a non-commercial Quantum Cascade Laser (QCL) source. The developed QEPAS and LITES sensors showed an excellent linear response and estimated minimum detection limits (MDL) of 13 ppb and 105 ppb, respectively, were obtained with a lock-in time constant of 100 ms
Architettura e digitale. Realtà estesa e intelligenza artificiale per progettazione, visualizzazione e costruzione architettonica
Get PDFL’obiettivo di questa ricerca è investigare il rapporto tra architettura
e tecnologie digitali, analizzando nello specifico il modo in cui la
disciplina architettonica si interseca con la realtà estesa e l’intelligenza
arti昀椀ciale generativa. Ciò è stato fatto organizzando il lavoro in due
fasi, una di ricerca teorica, per costruire un solido riferimento per le
successive analisi critiche, e una pratica, ovvero basata sul learning by
doing.
Quindi, inizialmente ci si è concentrati sulla ricostruzione della storia
delle tecnologie immersive e dell’intelligenza artificiale, cercando
di contestualizzarle e di comprendere quali siano stati e quali siano
tutt’ora gli utilizzi che vengono fatti di questi strumenti, attingendo
necessariamente a campi e approcci anche molto distanti da quelli
puramente architettonici.
La consapevolezza derivante da questo processo è stata immessa nella
seconda fase, durante la quale si sono svolte una serie di esperienze in
prima persona, applicando strumenti, tecniche e conoscenza raccolte a
progetti e sperimentazioni architettoniche di varia natura: progettazione,
didattica, valorizzazione e costruzione
Joint Localization, Synchronization and Mapping via Phase-Coherent Distributed Arrays
No full textExtremely large-scale antenna array (ELAA) systems emerge as a promising technology in beyond 5 G and 6 G wireless networks to support the deployment of distributed architectures. This paper explores the use of ELAAs to enable joint localization, synchronization and mapping in sub-6 GHz uplink channels, capitalizing on the near-field effects of phase-coherent distributed arrays. We focus on a scenario where a single-antenna user equipment (UE) communicates with a network of access points (APs) distributed in an indoor environment, considering both specular reflections from walls and scattering from objects. The UE is assumed to be unsynchronized to the network, while the APs can be time- and phase-synchronized to each other. We formulate the problem of joint estimation of location, clock offset and phase offset of the UE, and the locations of scattering points (SPs) (i.e., mapping). Through comprehensive Fisher information analysis, we assess the impact of bandwidth, AP array size, wall reflections, SPs and phase synchronization on localization accuracy. Furthermore, we derive the (ML) estimator for the joint localization, synchronization, and mapping problem, which optimally combines the information collected by all the distributed arrays. To overcome its intractable high dimensionality, we propose a novel three-stage algorithm that first estimates phase offset leveraging carrier phase information of line-of-sight (LoS) paths, then determines the UE location and clock offset via LoS paths and wall reflections, and finally locates SPs using a null-space transformation technique. Simulation results demonstrate the effectiveness of our approach in distributed architectures supported by radio stripes (RSs) - an innovative alternative for implementing ELAAs - while revealing the benefits of carrier phase exploitation and showcasing the interplay between delay and angular information under different bandwidth regimes
Mapping sustainable options in the fashion industry: A systematic literature review and a future research agenda
No full textThe fashion industry accounts for large impacts on the environment and social welfare, both on the consumers' and companies' sides. This study systematically reviews the literature on sustainable consumption in the fashion industry, clarifying sustainable fashion's meaning. Existing sustainable fashion solutions are investigated from consumers' behavior perspective and classified into three consumption phases, that is, (pre-)purchase, use, and post-use. 187 articles are included, and twenty-six sustainable solutions are identified across the consumption phases. These include techniques, features, services, and behaviors able to increase garment sustainability by mitigating negative impacts and ensuring product circularity by recycling and/or reusing at the product's end of life, representing promising strategies for fostering a transition toward sustainable fashion consumption practices. An innovative and comprehensive framework of sustainable fashion solutions is developed. Future research agenda and a sustainable offering inventory for marketers are provided
Cost-effective monitoring of structural risk of bridges supported by cutting-edge technologies
Get PDFBridges and viaducts are crucial components of transportation network, and activities as risk assessment and structural maintenance are crucial to avoid economic losses and casualties due to their collapse. External actions, natural hazards, material degradation and aging affect safety and serviceability of bridges. The effort required by national guidelines, as the one issued in 2020 in Italy, pose questions about the resources required for large-scale screening and risk assessment of large bridge portfolios, mostly populated by simply supported concrete girder bridges, both reinforced and prestressed (PSC). The main challenge is to leverage cutting-edge technologies for a cost-effective near-continuous monitoring of structural risk of bridges.
In the field of remote-sensing technologies, Interferometry via Synthetic Aperture Radar and Unmanned Aerial Vehicle photogrammetry are two emerging technologies that meet requirements to achieve the goal. Large coverage, adequate resolution and accuracy, and acquisition frequency are them strengthen points at the base of two proposed frameworks. The combination with basic structural knowledge of bridges and environmental data represents a promising mix for portfolio structural risk assessment of existing bridges and structures as demonstrated in the explored case studies.
Although these technologies are affected by limitations, their constant use can help to identify bridges requiring a more refined structural risk assessment based on traditional structural health monitoring systems (i.e., sensor-based). Some bridge typologies as PSC box-girder bridges pose additional challenges requiring more effective strategies to monitor prestressing force reduction. Machine learning surrogate models as Artificial Neural Networks coupled with eXplainability approaches are demonstrated to be effective when integrated with traditional sensor-based systems. The experimental campaign on a scaled PSC box bridge is a great example of this combination.
The cost-effective monitoring of structural risk of bridges supported by cutting-edge technologies is a true example of the ongoing change in civil engineering that will flourish in the years to come thanks to the technical and scientific progress
Stratificazioni. Dalla molteplicità originaria all’unità interiore tra le cose: un progetto per Larissa
No full textThe Enhanced Factory for Extra-Terrestrial Space Technology Operations: Conceptualization and Scenarios’ Definition
No full textThe Enhanced Factory for Extra-terrestrial Space Technology Operations (EFESTO) project presents a strategic approach for establishing sustainable manufacturing and recycling operations in Low Earth Orbit (LEO), aiming to mitigate launcher constraints, support long-duration missions, increase space stations independence from Earth resupply and enhance circularity of the resources in space. Utilizing Model-Based Systems Engineering (MBSE), this research aims at identifying and investigating the enabling technologies for in-space manufacturing (ISM) and waste management in microgravity environments. This paper details the comprehensive process, from conception to implementation, including environmental impact assessments and navigating market uncertainties. Preliminary findings demonstrate the project’s capacity to bolster space operations, indicating a shift towards a sustainable, service-oriented economy in space. The systematic structure of the project addresses a multitude of challenges, from the development of appropriate space technologies and waste management systems to strategic market and regulatory considerations. Ultimately, EFESTO aims to contribute significantly to extra-terrestrial development, enhancing the resilience and adaptability of space operations while promoting a circular economy and compliance with evolving space standards