Archivio istituzionale della ricerca - Alma Mater Studiorum Università di Bologna
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Active Power Sharing Control in Asymmetrical Bidirectional DC/DC Converter
Get PDFIn many practical applications, such as electric vehicle charging and smart transformers, reverse power flow is significantly lower than forward power flow. Designing a full-rated bidirectional DC/DC converter in such cases leads to increased hardware costs. To address this, recent research has explored isolated topologies that support asymmetrical bidirectional power flow at reduced cost. This manuscript investigates an asymmetrical bidirectional DC/DC (AB-DC/DC) converter that integrates a partial-scale active bridge and a partial-scale diode bridge connected in parallel on the secondary side. Passive power sharing between these bridges is controlled by selecting appropriate coupling inductors, but practical magnetic tolerances cause power imbalances. To mitigate this, a novel modulation technique is proposed to enable active power sharing, allowing power transfer from the diode bridge to the active bridge. The study covers various operating regions, including discontinuous conduction mode (DCM), continuous conduction mode (CCM), dual-active-bridge (DAB) mode, and two hybrid regions, where the diode bridge operates in DCM and the active bridge in CCM. Closed-form power expressions and boundary conditions are derived for all modes. The proposed strategy is validated through simulations and experimental measurements on a hardware prototype, demonstrating consistent waveform behavior and confirming the feasibility of active power transfer from the diode bridge to the active bridge
Creativity Unbound. Rethinking Audiovisual Authorship in the Artificial Intelligence Era
No full textThe advent of artificial intelligence (AI) has reshaped the debate on authorship in audiovisual media, challenging traditional notions of intellectual
property and creative agency. This paper explores the evolution of authorship from early cinematic theories to the rise of collaborative and intertextual media contents, ultimately questioning how AI-generated creative products should be attributed. By analyzing case studies, including AI-generated
films, TV shows and deepfake applications, we assess the implications of AI
as both a creative tool and a co-author. Legal and cultural perspectives are
considered, addressing copyright concerns and the function of AI in media
production. Our study argues that while AI introduces new complexities
in creative ownership, human oversight remains essential in shaping and
interpreting AI-assisted content. Ultimately, building on the ongoing transformation of media creation in the digital age, we claim that AI’s role in
authorship must be examined on a case-by-case basis
Virtual embodiment increases male sensitivity to catcalling experiences
Get PDFWomen are disproportionately subjected to the widespread social problem of street harassment. This study focuses on catcalling, a specific form of harassment characterized by unsolicited verbal or gestural comments often centered on physical appearance. To investigate the emotional and cognitive impact of this experience, we employ an immersive virtual reality (VR) paradigm wherein male participants embody a female avatar to experience street harassment firsthand. Participants’ emotional responses were assessed through both explicit self-reports, guided by Ekman’s emotion model, and implicit measures derived from a semantic analysis of their verbal reactions. Our findings reveal two primary outcomes: first, the experience elicited heightened feelings of anger and disgust, emotions frequently associated with moral disapproval; second, a significant correlation emerged between the intensity of these emotions and the subjective sense of virtual embodiment. This research also introduces an AI-driven method for simulating cognitive and neural patterns associated with the experience. These results underscore the potential of VR as a tool for promoting social safety, with significant applications for clinical and educational interventions
The role of media memorability in facilitating startups’ access to venture capital funding
No full textMedia reputation plays an important role in attracting venture capital investment. However, prior research has focused too narrowly on general media exposure, limiting our understanding of how media truly influences funding decisions. As informed decision-makers, venture capitalists respond to more nuanced aspects of media content. We introduce the concept of media memorability-the media's ability to imprint a startup's name in the memory of relevant investors. Using data from 197 UK startups in the micro and nanotechnology sector (funded between 1995 and 2004), we show that media memorability significantly influences investment outcomes. Our findings suggest that venture capitalists rely on detailed cues such as a startup's distinctiveness and connectivity within news semantic networks. This contributes to research on entrepreneurial finance and media legitimation. In practice, startups should go beyond frequent media mentions to strengthen brand memorability through more targeted, meaningful coverage highlighting their uniqueness and relevance within the broader industry conversation
Geo-Information for Humanitarian Mapping and Monitoring Crisis-Affected Regions: A Scoping Review
No full textThe migration crisis is generated by mass movements of population within or outside the national borders of a country. Triggers to this phenomenon include either sudden events, such as natural catastrophes (floods, earthquakes) or gradual social pressure (wars and civil unrest). This paper aims to analyse the effective cartographic methods of mapping changing patterns of human movements. Replaced settlements are visible from space and can be mapped effectively using satellite images processed by Geo-Information Systems (GIS). This review study presents a thorough in-depth analysis of the significant role of the ML and GIS and their incorporating into crisis control and monitoring migration situations. Machine Learning (ML) hold a significant role in processing geospatial referenced data which is essential for mapping humanitarian crisis using Earth observation data. This review study presents a thorough in-depth analysis of the significant role of the ML and GIS and their incorporating into crisis control and monitoring migration situations. Understanding the reasons of migratory movements is supported by the interrogation of the trajectories which can be detected from space for mapping the ways of the migration's paths. A systematic literature review was performed, synthesizing findings from existing approaches, geospatial analysis and field observations related to humanitarian mapping. This study reveal that integrated use of ML, GIS and EO data can facilitate mapping the endangered areas for sustainable planning during crisis events across multiple spatiotemporal scales
Partial correlation as a tool for mapping functional-structural correspondence in human brain connectivity
No full textBrain structure-function coupling has been studied in health and disease by many different researchers in recent years. Most of the studies have estimated functional connectivity matrices as correlation coefficients between different brain areas, despite well-known disadvantages compared with partial correlation connectivity matrices. Indeed, partial correlation represents a more sensible model for structural connectivity since, under a Gaussian approximation, it accounts only for direct dependencies between brain areas. Motivated by this and following previous results by different authors, we investigate structure-function coupling using partial correlation matrices of functional magnetic resonance imaging brain activity time series under various regularization (also known as noise-cleaning) algorithms. We find that, across different algorithms and conditions, partial correlation provides a higher match with structural connectivity retrieved from density-weighted imaging data than standard correlation, and this occurs at both subject and population levels. Importantly, we also show that regularization and thresholding are crucial for this match to emerge. Finally, we assess neurogenetic associations in relation to structure-function coupling, which presents promising opportunities to further advance research in the field of network neuroscience, particularly concerning brain disorders
Album Casiraghi. Diario fotografico di un critico. Ediz. illustrata
No full textLa narrazione dei fatti storici, sociali e culturali di un Paese, tradizionalmente affidata ai documenti scritti, uniche fonti ritenute per lungo tempo affidabili e veritiere per una ricostruzione realtmente profonda della realtà, si arricchisce in questo volume di un plus percettivo, di sfumata ma immediata evidenza, che mostra al lettore una concretezza oggettiva che alla parola, oltre un certo confine, è fatalmente preclusa. Le immagini di Album Casiraghi, non solo tecnicamente "fantastiche" ma oggettivamente concrete, illuminano nel volume la narrazione che qui si fa Storia, diventando esse stesse documenti dall'enorme valenza testimoniale. Album Casiraghi svela, attraverso il suo archivio inedito e "multitipologico", gli schemi e i modelli sociali e culturali di un approccio moderno alla critica cinematografica e permette di ricostruire l'essenza di un'epoca e di un Paese, dei suoi cambiamenti e delle sue verità
L'outdoor learning come percorso verso l'inclusione e l'innovazione nella scuola secondaria di primo grado = Outdoor learning as a pathway to inclusive and innovative practices in middle schools
No full textThe paper presents a research project aimed at describing how
outdoor learning is configured in the Italian context of lower
secondary schools, with attention to the promotion of inclusive
processes, educational well-being and student motivation. The
research, launched in 2023 and co-conducted by Indire, the
University of Bologna and the Rete delle Scuole all'Aperto, involved
240 schools belonging to three national networks of schools
characterized by a common pedagogical vision centered on outdoor
learning and school innovation. The explanatory sequential mixed
methods study design included a first quantitative phase, followed by a second qualitative phase aimed at deepening the phenomenon
initially detected on a large scale
Mechanical and fatigue response of high-alloyed carbon spring steels: Impact of different heat treatments
No full text60MnSiCr4 and 52SiCrNi5 are two high-strength steels whose applications involve many different industrial sectors. They can be used for bolts and springs and have wide applications in the field of automatic machines and machine tools for gripping devices and collet fabrication, as they take advantage of their strength, toughness and machinability. Nevertheless, literature scientific data are currently lacking, which was the main motivation for this thorough study aimed at a detailed characterisation of the mechanical response of these materials. Both static and fatigue properties have been experimentally investigated, complying with the recommendations of the related International Standards, with the aim of comparing the performance for different hardness values for each material. Moreover, the impact of heat treatment on geometry deformation was also studied, to compare the repeatability of the process and related outcomes between the two observed steels. The following statistical processing of the experimental campaign data led to determining the main material mechanical properties: yield point, ultimate tensile strength, elongation and Young’s modulus regarding static parameters. A careful fatigue experimental campaign led to the determination of S-N curves and fatigue limits, thus enabling lifespan prediction and comparisons among the expected strengths. In addition, fractography analyses were conducted to assess the behaviour of crack propagations for the studied materials and conditions. Finally, Vickers tests by a microdurometer were performed to validate the uniform distribution of hardness values along the thickness