Politecnio die Bari - Catalogo di prodotti della Ricerca
Not a member yet
36616 research outputs found
Sort by
Digital Twins Facing the Complexity of the City: Some Critical Remarks
No full textThe concept of a digital twin (DT), rooted in mid-20th-century ideas, has recently gained significant traction even outside software simulation and engineering modeling. The recent advancements in computational power and the development of model integration methodologies have enabled the creation of virtual replicas of complex physical objects. The success of DTs in engineering has also pushed for the exploration of their use in other domains, especially where complex systems are at stake. One of these cases, which is the focus of this paper, is the modeling of cities and the way they are transformed via technologies into so-called smart cities. In these systems, the huge amount of data that are made accessible and constantly updated via sensor networks suggests that one can use DTs dedicated to the urban scenario as data-driven decision-making devices. However, the concept of a DT was not developed for socio-technical systems and requires careful analysis when applied to urban scenarios. While technologies and information systems have become integrated into city management, this has not reduced the complexity of the city. Relying only on sensory data for city modeling and management seems pretentious since detectable data (what is made accessible via sensor networks) do not seem suitable to inform on all important aspects of the city. Urban DTs hold promise, yet their development necessitates careful consideration of both opportunities and limitations. For this goal, it can be helpful to exploit an ontological analysis due to its neutral and systematic approach and to look at a city as a system of intertwined relationships across its components, such as places, agents, and knowledge. The variety of interactions that the components manifest highlights aspects of the city that the type of data we can collect today leaves unexplored. The paper presents a preliminary example of this issue by studying cases of city squares. The final part of this paper is a call to analyze DTs’ potential role in urban contexts and become aware of the intrinsic limitations of the data they rely upon
Avanzamento nelle metodiche di caratterizzazione geo-idro-meccanica dell'attività di frane antiche a cinematica lenta
No full textLa diagnosi di una frana, basata sull’analisi dei processi che avvengono all’interno del versante e che ne determinano la rottura, è fondamentale per selezio-nare le più adeguate, sostenibili e durature misure di mitigazione del rischio. Ciò ri-sulta particolarmente articolato per paleo-frane profonde, molto lente, che inficiano la sicurezza e la funzionalità del costruito.
Secondo l’approccio della Stage Wise Methodology (Cotecchia et al., 2020), applicato al caso di studio, il lavoro di ricerca condotto è approdato alla diagnosi di un complesso meccanismo franoso, ossia quello che coinvolge il versante occiden-tale del Comune di Chieuti, nel Sud Italia, che può essere considerato quale prototipo di numerose paleo-frane che si insediano in successioni sabbioso-argillose.
La valutazione del rischio da frana e la progettazione di adeguate misure di mitigazione del rischio devono basarsi su una diagnosi completa del meccanismo di frana, ovvero sulla caratterizzazione delle cause predisponenti e innescanti la rottura interna al pendio, nonché l’attività e la sua progressiva evoluzione nel tempo. Essen-do il processo il risultato finale di una sequenza di fenomeni deformativi naturali, complessi e in interazione tra loro all’interno del pendio, l’interpretazione fenomeno-logica del meccanismo di frana, prima fase prevista dalla metodologia, deve scaturi-re da un’analisi interdisciplinare dei dati risultanti dalle indagini geologiche, geomor-fologiche, geotecniche, strutturali e geomatiche. Successivamente, le analisi a ritroso dell’equilibrio limite e la modellazione numerica della rottura del pendio devono vali-dare l’interpretazione fenomenologica, supportando così la diagnosi della frana.
Questo approccio interdisciplinare è stato adottato per l'analisi di un proces-so franoso profondo e molto lento che ha interessato il versante occidentale di Chieuti (Sud Italia), identificato come versante prototipo. L'attività franosa attuale ri-guarda una paleo-frana, plausibilmente innescata, durante il Quaternario, dall’erosione asimmetrica fluviale valliva. Pertanto, le sfide affrontate nell’analisi di questo caso di studio prototipo potrebbero essere rilevanti per la diagnosi di altri processi franosi molto lenti e profondi.
Chieuti è un piccolo comune situato sulla sommità di una collina, a 221 m s.l.m., dove affiorano depositi continentali a cui soggiacciono successioni marine (sabbie, limi e argille). Il versante occidentale del versante è attualmente coinvolto in processi franosi molto lenti che danneggiano diffusamente l'abitato a partire dal XIX secolo, nonostante l’avvicendarsi di numerose opere di mitigazione (es. strutture di contenimento e misure di regimentazione delle acque piovane), realizzate negli ultimi 60 anni. Si registra attualmente una significativa attività del processo franoso.
Durante il periodo 2020-2023 è stata condotta un’indagine approfondita dei fattori di pendio volta a caratterizzare il processo franoso per la progettazione di mi-sure di mitigazione a lungo termine. Sono stati eseguiti rilievi geologici, geomorfolo-gici e idrogeologici in sito, fotointerpretazione aerea e analisi dei dati provenienti da archivi storici, prove in sito (ad es. tomografia di resistività elettrica, rifrazione sismi-ca delle onde P, prove di permeabilità) e monitoraggio piezometrico. Le caratteristi-che litologiche e mesostrutturali dei carotaggi del terreno sono state analizzate nel dettaglio, integrandole con i dati geotecnici risultanti dalle prove di laboratorio. Gli spostamenti del suolo in profondità e in superficie lungo il versante occidentale sono stati misurati rispettivamente mediante monitoraggio inclinometrico e topografico. In particolare, gli spostamenti del suolo sono stati rilevati mediante tecniche Radar In-terferometriche ad Apertura Sintetica Multi-Temporale (MTInSAR) e monitoraggio tramite Stazione Totale Automatizzata.
Dall’interpretazione fenomenologica condotta sulla base di tutti questi dati, si è dedotto che il processo franoso in atto, lungo il versante occidentale di Chieuti, sia da interpretarsi come stadio evolutivo, nel lungo termine, dei processi di localizza-zione delle deformazioni profonde al piede, avvenuti nel passato geologico, inne-scanti il primo processo di rottura. Il processo paleo-franoso dovrebbe aver interes-sato dapprima il settore settentrionale del versante, spostandosi poi verso Sud. Ad oggi sono state rilevate due principali frane roto-traslative profonde, che convergono in un’unica banda di taglio con il piede in corrispondenza dell’affluente meridionale del torrente Fico, sito a valle.
L'evoluzione retrogressiva del processo franoso ha interessato l’area urba-nizzata, attualmente confinata da due scarpate di frana che delimitano, a monte, un corpo caratterizzato prevalentemente da spostamenti verticali, coerenti solo con una superficie di scivolamento profonda che affiora sub-verticalmente in corrispondenza del piano campagna. La stabilità di questa porzione di pendio è legata non solo alle forze di taglio mobilizzate, ma, soprattutto, all’attività del dei corpi più attivi a valle, i cui movimenti orizzontali possono provocare lo scarico laterale del cuneo a monte.
L'interpretazione fenomenologica del meccanismo di frana è stata validata mediante analisi a ritroso dell’equilibrio limite, implementando il regime piezometrico ricavato da una simulazione FE della infiltrazione stazionaria nel pendio, coerente con i dati piezometrici di sito, e con la modellazione numerica della storia geologica del versante.
Conclusa l’interpretazione cinematica, si è condotta un’interpretazione dina-mica del problema, osservando l’evoluzione nel tempo degli spostamenti superficiali e profondi, dei livelli piezometrici (rilevati con celle di Casagrande e piezometri elet-trici) e delle loro variazioni, e dell’inclinazione del muro di contenimento (rilevati at-traverso tiltmetri ad alta precisione). L’integrazione di questi dati e il confronto con i rilievi dello stato di danno dell’edificato hanno consentito di definire meglio la dina-mica del processo franoso, considerando anche eventuali fenomeni di creep.
Infatti, lo studio dei dati di spostamento nel tempo, dei dati di monitoraggio piezometrico nel versante e di quelli indicativi della morfologia evolutiva del fosso a valle, hanno permesso di diagnosticare in che termini tale attività sia connessa a va-riazione delle azioni interne ed esterne di pendio, determinanti variazioni di equilibrio cui conseguono evoluzioni della deformazione in campo elasto-plastico, ed in che limiti vada invocata la deformazione secondaria, o creep, quale causa dei movimenti lenti di tali corpi franosi.
In ultimo, si è dato un contributo nell’avanzamento nell’applicazione scientifi-ca della SWM su area vasta, finalizzando lo studio ad una crescita nella metodologia di gestione della sicurezza delle infrastrutture da parte di enti gestori (caso di studio di un tratto dell’Autostrada A16, tra Grottaminarda e vallata, km 81-104 direzione Napoli-Bari).
In conclusione, in questo lavoro di ricerca si affronta la diagnosi di un com-plesso paleo-frana attualmente attivo che interagisce con l'area urbanizzata di Chieuti, evidenziando le problematiche affrontate durante il processo interpretativo. Questo prototipo di caso di studio può essere considerato un esempio della complessità della diagnosi di un meccanismo franoso, soprattutto quando si ha a che fare con paleofrane a movimento molto lento. Infatti, attestate le basse velocità di spostamen-to (pochi mm/anno), la definizione della morfologia di tali corpi di frana può essere perseguita solo attraverso un monitoraggio degli spostamenti di lungo termine, im-plementando il rilievo degli inclinometri profondi tramite sensori ad alta risoluzione. In questi casi, l’analisi stratigrafica può richiedere una risoluzione dei dati di circa un metro per cogliere con precisione la dislocazione delle unità litostratigrafiche, mentre la caratterizzazione cinematica del campo di spostamento della superficie terrestre può richiedere una risoluzione centimetrica. Lo stesso vale anche per altre tecniche adottate per la diagnosi del meccanismo di rottura, che dovrebbero essere in grado di individuare gli esigui incrementi di spostamento/deformazione. Si ribadisce dun-que, quanto l’analisi di tutti i dati e processi relativi ai pendii è, quindi, cruciale per la definizione di misure di mitigazione delle frane adeguate e sostenibili.The diagnosis of a landslide, based upon the knowledge of the processes occurring in the slope and determining its failure, is fundamental for selecting the more sustainable and long-lasting mitigation measures. It may be particularly chal-lenging for deep paleo-landslides characterised by very slow movements, jeopardiz-ing the safety of the built environment.
According to the Stage Wise Methodology approach (Cotecchia et al., 2020), applied to the case study, this thesis presents the diagnosis of a complex landslide mechanism, the one affecting the town of Chieuti in southern Italy, which could be considered as a prototype of several paleo-landslides involving sandy-clayey suc-cessions.
The landslide risk assessment and the design of sustainable mitigation measures should be based on a comprehensive diagnosis of the landslide mecha-nism, i.e. the characterisation of the predisposing and triggering causes of slope fail-ure, along with its expected progression with time. Being the final process of a se-quence of natural, complex and coupled deformation phenomena in the slope, the phenomenological interpretation of the landslide mechanism, the first phase suggest-ed by the methodology should arise from an interdisciplinary analysis of data result-ing from geological, geomorphological, geotechnical, structural and geomatic inves-tigations. Thereafter, the limit equilibrium back analysis and the numerical modelling of the slope failure should validate the phenomenological interpretation, thus support-ing the landslide diagnosis.
This interdisciplinary approach has been adopted for the analysis of a deep, very slow-moving landslide process involving the western slope of Chieuti (southern Italy), herein selected as a prototype slope. The current landslide activity concerns a paleo-landslide, probably triggered by river erosion at the toe of the hill during the Quaternary. Therefore, the challenges faced within the analysis of this prototype case could be relevant for the diagnosis of other very slow-moving and deep slope failure processes.
Chieuti is a small town located on the top of a hill, at 221 m a.s.l., where con-tinental deposits, overlaying marine successions (sands, silts and clays), outcrop. The western side of the hillslope is currently involved in slow-moving landslides, which have been damaging the built-up area since the 19th century, despite the sev-eral mitigations works (e.g., retaining structures and storm water management measures) carried out during the last 60 years and currently affected by the instability process.
During the 2020-2023, a comprehensive investigation of the slope factors has been carried out aimed at characterising the landslide process for the design of long-lasting mitigation measures. Geological, geomorphological and hydrogeological field surveys have been performed, together with aerial-photointerpretation and the analysis of the data coming from historical archives, field testing (i.e., electrical re-sistivity tomography, P-waves seismic refraction, permeability tests) and piezomet-ric monitoring. The lithological and meso-structural features of the soil corings have been analysed in detail, integrating them with the geotechnical data resulting from la-boratory testing. The soil displacements at depth and at the ground surface along the western slope have been measured through inclinometric and topographic monitor-ing, respectively. In particular, the ground displacements have been detected through Multi-Temporal Interferometric Synthetic Aperture Radar (MTInSAR) techniques and Automated Total Station monitoring.
From the phenomenological interpretation, based on all the discussed data, the current landslide process affecting the western slope of Chieuti has been inter-preted as a long-term evolution stage of deep strain localisation processes occurred in the past, triggered by its geological history. The paleo-landslide process should have involved at first the norther sector of the hillslope, moving towards south. Now-adays, two main deep roto-translational landslides have been detected, joining within a single shear band with the toe at the southern tributary of the Fico stream.
The retrogressive evolution of the landslide process involved the urbanised area, which is currently dislocated by the landslide scarps that delimite a body char-acterised by predominant vertical displacements, coherent only with a deep shear band outcropping sub-vertically at the ground surface. The stability of this slope por-tion is related not only to the mobilised shear strengths, but, more importantly, to the activity of the most active downstream bodies, whose horizontal movements may cause unloading at the toe of this body.
The phenomenological interpretation of the landslide mechanism has been validated by means of limit equilibrium back-analyses, implementing the piezometric regime retrieved from a FE simulation of the steady-state seepage in the slope, co-herent with the in-situ piezometric data, and with the numerical modeling of the slope’s geological history.
Once the cinematic interpretation was concluded, a dynamic interpretation of was conducted, observing the evolution over time of the superficial and deep dis-placements, of the piezometric levels (detected with Casagrande cells and electric piezometers) and of the retaining wall inclination (measured using high-precision tilt-meters). The integration of this data and their comparison with the building damage state survey have allowed us to better define the dynamics of the landslide process, also considering creep phenomena.
Indeed, the study of displacement data over time, piezometric monitoring da-ta on the slope, and those indicating the evolving morphology of the downstream gully, have made it possible to diagnose how such activity is related to the variation of internal and external slope forces, leading to changes in equilibrium that result in the evolution of deformation in the elastic-plastic field, and to what extent secondary deformation, or creep, should be invoked as the cause of slow movements of such landslide bodies.
Finally, a contribution has been made to the advancement of the scientific application of SWM on a large scale, focusing the study on the development of a methodology for managing the safety of infrastructure by managing authorities (case study of a stretch of the A16 highway, between Grottaminarda and Vallata, km 81-104, direc-tion Naples-Bari).
In conclusion, the thesis reports the diagnosis of a currently active complex paleo-landslide interacting with the urbanised area of Chieuti, highlighting the issues faced during the interpretation process. This prototype case study may be consid-ered example of the complexity lying within the diagnosis of a landslide mechanism, especially when dealing with very slow-moving paleo landslides. Indeed, given the low displacement rates (i.e., few mm/year), the assessment of the morphology of such landslide bodies can be pursued only through a long-lasting displacement mon-itoring, implementing the survey of deep inclinometers through high-resolution sen-sors. In these cases, the stratigraphic analysis may require a data resolution of about one meter to accurately catch the dislocation of the soil units, while the kinematic characterisation of the ground surface displacement field may need a centimetre res-olution. The same applies also to other techniques adopted for the diagnosis of the failure mechanism, which should be able to catch low displace-ment/strain/disturbance levels. Such analysis of all the slope data and processes is, then, crucial for the definition of appropriate and sustainable landslide mitigation measures
Analyzing the water-energy-food-ecosystem nexus by integrating hydrological modeling and system dynamics tools
Get PDFEffective and integrated management of natural resources is crucial for achieving sustainability, particularly in the context of interrelated challenges posed by using these resources. This study addresses four complementary as-pects of resource management using a ‘Nexus’ approach within the Tarquinia/ Marta River, highlighting how this region serves as a model that could be ap-plied to other areas of the Mediterranean. The study proposes an innovative approach based on System Dynamics Modeling techniques and hydrological modeling, which is summarized below.
The first chapter emphasizes the Nexus concept, which has gained inter-est as a theoretical framework for understanding the complex interconnections among natural resources. It highlights the need for tools and methods to effec-tively map and analyze these interdependencies, facilitating stakeholder en-gagement in sustainability transitions. In this context, the study employs a Par-ticipatory System Dynamics Modeling (PSDM) approach to enhance the under-standing and management of the Water-Energy-Food-Ecosystem Nexus (WEFE Nexus). This approach is tested concerning the Tarquinia plain in Italy, where a strong interdependency and conflict exists between agriculture and environ-mental conditions. The approach aims to achieve stakeholder consensus on challenges arising from conflicts between different sectors and subsectors in areas under intensive agricultural activity, while also considering future chang-es due to climate change. The analysis of the Causal Loop Diagram (CLD) helps identify the main challenges for the area and highlights the need for a better understanding and modeling of key phenomena. The centrality of agricultural activities, in terms of productivity, relevance for farmers, and impacts on water quality and natural areas, underscores the necessity of investigating these im-pacts and potential mitigation measures using specific agro-hydrological mod-els.
The second chapter builds on the main challenges identified using PSDM and proposes well-established hydrological modeling (SWAT) to further en-hance the understanding and management of the WEFE Nexus. In line with the research objectives, the SWAT model has been utilized with the available da-tasets to first establish the current conditions in the watershed and, secondly, to develop specific scenarios representing the effects of climate change. The Sequential Uncertainty Fitting algorithm version 2 (SUFI-2), a part of the SWAT-CUP tool package, has been employed for calibration, validation, and sensitivity analysis. Data from the EURO-CORDEX initiative includes various climate models involving regional climate models (RCMs) nested in different global circulation models (GCMs) used in this study. Historical experiments and future projections (based on the RCP 8.5 worst-case greenhouse gas emission scenario) have been selected. The most reliable EURO-CORDEX climate projec-tions have been selected following a rigorous performance evaluation of sever-al high-resolution combinations (GCMs-RCMs) over the area. This section of the study has investigated the hydrological balance, soil erosion and nutrient yield in the study watershed, focusing particularly on agricultural practices and cli-mate change impacts. The study findings have revealed significant soil loss and changes in total nitrogen (TN) and total phosphorus (TP) yield under both cur-rent and future scenarios, with agricultural practices exacerbating these issues. Conclusively, this chapter highlights the need for the implementation of effec-tive management strategies and mitigation measures to address these chal-lenges.
The third chapter explores the implementation of Best Management Practices (BMPs) to address on- and off-site impacts resulting from soil erosion and nutrient pollution in the study area, a region susceptible to these environ-mental challenges due to its Mediterranean climate and intensive agricultural practices. Utilizing the Soil and Water Assessment Tool (SWAT), the study as-sesses different individual BMPs, such as terracing, contour farming, no-tillage, and residue management as well as their combination. The results underscore the effectiveness of combined BMPs in reducing erosion and nutrient pollution, with terracing being particularly impactful in minimizing soil loss in hotspot ar-eas within the watershed and reducing sediment and nutrient loading into the river. The analysis emphasizes the importance of integrated BMP approaches for sustainable soil and water management in agricultural areas as well as highlighting the need for targeted management strategies to mitigate envi-ronmental impacts and enhance water quality.
The last chapter focuses on the application of PSDM, describing how a transition from Causal Loop Diagrams to quantitative models (stock and flow) can help explore potential future trajectories of the system under various condi-tions, particularly aiming to enhance its resilience. Stakeholders, including poli-cy and decision-makers, were actively involved in co-designing, analyzing, and discussing relevant scenarios. The study emphasizes the integration of stake-holder knowledge with technical modeling efforts to identify sustainable man-agement strategies for water resources, ecosystems, and agricultural practices in the region. At the core of the chapter is the development of a comprehensive stock and flow model, coupled with the SWAT hydrological model, to investi-gate the long-term impacts of agricultural practices on water resources and ecosystem sustainability. This integrated modeling approach enables a detailed analysis of how management strategies, particularly those involving Nature-Based Solutions (NBS) affect water quantity, quality, and agricultural productiv-ity under varying climate change scenarios. Besides supporting system under-standing, the proposed approach showed the potential to foster stakeholder di-alogue, which is crucial for building consensus on sustainable development pathways for the area. Key methodological challenges and potential needs for further innovation are also included
Search for charged-lepton flavor violation in the production and decay of top quarks using trilepton final states in proton-proton collisions at s=13 TeV
No full textA search is performed for charged-lepton flavor violating processes in top quark ((Formula presented)) production and decay. The data were collected by the CMS experiment from proton-proton collisions at a center-of-mass energy of 13 TeV and correspond to an integrated luminosity of (Formula presented). The selected events are required to contain one opposite-sign electron-muon pair, a third charged lepton (electron or muon), and at least one jet of which no more than one is associated with a bottom quark. Boosted decision trees are used to distinguish signal from background, exploiting differences in the kinematics of the final states particles. The data are consistent with the standard model expectation. Upper limits at 95% confidence level are placed in the context of effective field theory on the Wilson coefficients, which range between (Formula presented) depending on the flavor of the associated light quark and the Lorentz structure of the interaction. These limits are converted to upper limits on branching fractions involving up (charm) quarks, (Formula presented) ((Formula presented)), of (Formula presented), (Formula presented), and (Formula presented) for tensorlike, vectorlike, and scalarlike interactions, respectively
Emerging Technologies, Institutional Groups and Inter-organisational Networks: The Case of Microneedles
No full textThis paper extends our understanding of how institutional logics contribute to inter-organisational collaboration formation during the emergence of a technology. We classify organisations into five institutional groups – Government (GOV), Healthcare (HC), Industry (IND), Non-Governmental (NGO), and Research and Higher Education (RHE). We then examine the extent to which collaborative relationships within (homophily) and across (heterophily) these groups shape network dynamics. We focus on an emerging technology, namely, microneedles, and estimate a series of Exponential Random Graphs Models (ERGMs) using publication co-authorship data. Our analysis provides evidence that institutional homophily contributes to the formation of inter-organisational ties – indicating that organisational actors tend to establish ties within their group rather than across different groups. However, the impact of this mechanism varies across groups and phases of technological emergence. In the early development stages, institutional homophily drives the formation of homophilous ties within the GOV and IND groups, where collaborations focus on basic technical challenges. This is followed by the HC group, where collaborations centre around clinical applications. In the later development stages, homophily continues to influence the formation of intra-group ties among the GOV, IND, HC, and NGO groups, with collaborations expanding to clinical applications and informing decision-making processes
Integrated IoT-based production, deep learning, and Business Intelligence approaches for organic food production
No full textThe organic food processing industry grapples with several complex challenges, such as ensuring the ingredients' authenticity, reducing resource consumption, and maintaining consistent product quality despite fluctuating demand and the supply seasonal nature. Previous methodologies often lacked integration of real-time data and advanced predictive analytics, leading to inefficiencies and increased waste. This study proposes a novel framework that combines IoT sensor networks, deep learning algorithms, and business intelligence to optimize production processes in organic tomato processing. By employing a Long Short-Term Memory (LSTM) model, the framework effectively predicts sales, manages raw material procurement and enhances logistics based on real-time data inputs. Findings indicate a 25 % improvement in productivity and a 20 % reduction in waste during production, alongside a 30 % increase in profitability attributed to informed pricing strategies and enhanced supplier quality management. The integration of predictive analytics not only aligns production with consumer demand but also supports sustainable practices by minimizing overproduction and waste. This work addresses the critical intersection of technology and sustainability in food production, ultimately contributing to a more resilient and efficient organic food supply chain. Keywords: Organic food, data mining, deep learning, Business Intelligenc
Cosmic-ray acceleration and escape from supernova remnant W44 as probed by Fermi -LAT and MAGIC
No full textContext. The supernova remnant (SNR) W44 and its surroundings are a prime target for studying the acceleration of cosmic rays (CRs). Several previous studies established an extended gamma-ray emission that is set apart from the radio shell of W44. This emission is thought to originate from escaped high-energy CRs that interact with a surrounding dense molecular cloud complex. Aims. We present a detailed analysis of Fermi-LAT data with an emphasis on the spatial and spectral properties of W44 and its surroundings. We also report the results of the observations performed with the MAGIC telescopes of the northwestern region of W44. Finally, we present an interpretation model to explain the gamma-ray emission of the SNR and its surroundings. Methods. We first performed a detailed spatial analysis of 12 years of Fermi-LAT data at energies above 1 GeV, in order to exploit the better angular resolution, while we set a threshold of 100 MeV for the spectral analysis. We performed a likelihood analysis of 174 hours of MAGIC data above 130 GeV using the spatial information obtained with Fermi-LAT. Results. The combined spectra of Fermi-LAT and MAGIC, extending from 100 MeV to several TeV, were used to derive constraints on the escape of CRs. Using a time-dependent model to describe the particle acceleration and escape from the SNR, we show that the maximum energy of the accelerated particles has to be '40 GeV. However, our gamma-ray data suggest that a small number of lower-energy particles also needs to escape. We propose a novel model, the broken-shock scenario, to account for this effect and explain the gamma-ray emission
On the development of vehicle dynamics active systems: The handling stability ratio as a strategic indicator for integrating multiple actuators
No full textMechatronic systems for enhancing vehicle dynamics are a widely studied topic, especially in relation to high-performance vehicles, which must be characterized by high levels of handling capability and stability, as well as "natural"driving behavior. Despite the broad availability of research on the integration and control of multiple active systems, there is a lack of discussion on how they can effectively extend the range of achievable vehicle performance. To address the gap, this paper introduces and analyzes a novel performance indicator, the Handling Stability Ratio (HSR). HSR is the ratio of the maximum lateral grip level of the rear axle to that of the front one, and can be computed along the ISO open-loop steady-state circular tests. By means of HSR, it is possible to quantify the relative axle force reserve that is available for exploitation by an active system. The study considers how different chassis control actuations, namely Front Active Camber (FAC), Rear Active Camber (RAC), Rear Wheel Steering (RWS), and Rear Torque Vectoring (RTV), can virtually vary HSR, thereby increasing the cornering or stability performance in limit handling conditions, compared to the corresponding passive vehicle. In the initial vehicle setup phase, HSR can be adopted for obtaining the vehicle-level performance limit, and, when coupled to the actuator limits, provides the feasibility range of the considered chassis actuation suite
Integrated microphotonic platform for highly sensitive virus detection
No full textChip-scale micro-photonic biosensors have matured significantly over the past two decades, with various platforms developed for detecting biomarkers, including proteins in biological fluids. The COVID-19 pandemic has further accelerated research in virus detection, leading to the development of resonant and interferometric biosensors for identifying viruses like SARS-CoV-2. Despite these advancements, there remains a need for technical solutions that ensure point-of-care features such as low cost, rapid response, and low limit-of-detection (LoD). This paper presents an integrated silicon nitride microphotonic platform based on ring resonator technology, specifically designed for highly sensitive virus detection. The sensors, fabricated using strip and slot waveguides, are tested under flow conditions using ethanol and BSA-antiBSA solutions to evaluate bulk and surface sensitivity. The results indicate that the slot waveguide-based ring resonators exhibit the highest sensitivity. The platform uses functionalization protocols to immobilize specific antibodies for detecting SARS-CoV-2. The sensor successfully identifies the target analyte at concentrations as low as 1.5 nM, with a LoD of 36 pM using in situ functionalization, underscoring the importance of antibody orientation through an intermediate protein A layer. These results demonstrate the platform's potential for rapid and sensitive virus diagnosis and represent a significant step toward the development of portable, point-of-care diagnostic technologies for infectious disease monitoring