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An ECG compression method exploiting a QRS detector for sparse dictionary learning
No full textThis paper presents a Compressed Sensing (CS) method for electrocardiogram (ECG) using sparse dictionary learning for dimensionality reduction that exploits frames of one heart-depolarization cycle. The ECG signal is first acquired at the Nyquist rate and then segmented into multiple frames, with each frame aligned depending on the QRS complex positions detected by the Pan-Tompkins algorithm. During the training phase, a dictionary built through the Discrete Cosine Transform (DCT) is reduced through the Multiple Measurement Vector (MMV) algorithm. The compression employs the Deterministic Binary Block Diagonal (DBBD) matrix as a sensing matrix. The ECG frames are reconstructed by solving the MMV problem, and individual frames are aligned based on the R-peak value. This proposed method enables efficient data compression while preserving essential ECG signal information. The method achieves a high compression ratio of 12 while maintaining a low PRD, demonstrating its efficiency without compromising signal quality. Reconstruction quality was evaluated using both Weighted Diagnostic Distortion (WDD) and the Wavelet Energy–based Diagnostic Distortion (WEDD) metrics, showing very good to good WDD values up to CR = 12 and WEDD values indicating very good to excellent reconstruction
Olive pruning management with mobile laser scanner
No full textThe majority of Italian olive orchards are small-scale farms that differ in management styles. The management of pests, irrigation, and pruning is becoming more challenging due to the rise in extreme meteorological events brought on by climate change. Olive orchard pruning, a major postharvest cost in olive farming, is becoming increasingly important due to labour shortages. In medium to low-density orchards, the polyconic vase with a less geometrical order was introduced to simplify and expedite pruning, but it requires very specialized labour. In high-density orchards with a hedgerow canopy, the pruning is simplified with mechanical interventions, but this system struggles to maintain constant yields from year to year. Both orchard systems would benefit from a decision support system that could better organize pruning operations in large farms or productive areas with multiple farms lacking specialized labour. This experimental work has tested different pruning techniques and intensities in a medium-density orchard (polyconic vase) and a super high-density orchard, supported using a mobile laser scanner (MLS) for canopy volume measurements. The different pruning intensities were described by point cloud data before and after the pruning and again after 2 years. Different pruning intensities can be detected by MLS in both density systems in all cultivars and likely the measurements can be useful for a pluriannual organization of pruning in large farms or communities
A general duality theory for nonsmooth cone-constrained optimization
No full textMany real-world optimization problems in engineering, economics, and control systems involve nonsmooth objectives and complex constraints that violate classical regularity assumptions. Standard duality theories often fail in these settings, particularly when dealing with nonconvexity, nondifferentiability, or complementarity-type structures. This paper develops a generalized duality framework for cone-constrained optimization problems based on two mild assumptions: calmness of the constraint mapping and -pseudoinvexity of the objective function. These conditions enable strong, weak, and converse duality theorems without requiring classical constraint qualifications. Using Mordukhovich subdifferential calculus, we derive optimality conditions and construct dual models that avoid active-set identification and product-type constraints. While mathematical programs with vanishing constraints (MPVC) are recovered as special cases, our framework is substantially more general. Beyond the theoretical contributions, we design a primal–dual subgradient algorithm grounded in nonsmooth variational principles. We prove its convergence and demonstrate its practical effectiveness through illustrative numerical examples
Non-Destructive Measurements for Functional Quality Control of Additively Manufactured Components through Tomographic Optical Flow
No full textLa crescente diffusione della Manifattura Additiva (AM) per componenti strutturalmente e funzionalmente avanzati ha reso necessarie tecniche non distruttive in grado di valutare la risposta meccanica di materiali complessi. Questo lavoro propone un metodo di controllo qualità funzionale per metamateriali stampati in 3D basato esclusivamente su tomografia computerizzata a raggi X (CT), senza traccianti artificiali o particelle per aumentare la texture. La tesi esamina innanzitutto lo stato dell’arte della misura di deformazioni da CT, evidenziando i limiti della Digital Volume Correlation (DVC) e dei metodi di optical flow applicati a materiali ingegnerizzati e componenti AM. Vengono poi sviluppati una procedura dedicata e nuovi algoritmi di analisi, progettati per operare su dataset CT poveri di texture artificiale, evitando la seminagione e mantenendo la compatibilità con sistemi micro-CT da laboratorio. Segue uno studio sistematico dei limiti prestazionali, dell’accuratezza, dell’incertezza e della sensibilità su dati sintetici controllati e casi studio sperimentali. Il contributo principale è un framework di deep optical flow 2,5D basato su RAFT (Recurrent All-Pairs Field Transforms): i volumi CT scarico/carico sono elaborati per sezioni lungo le tre direzioni principali e, su ciascuna sezione, RAFT stima un campo di moto denso nel piano, producendo sei campi volumetrici direzionali. Questa formulazione slice-wise preserva la risoluzione a livello voxel evitando il costo di una correlazione 3D completa. La validazione su cinque dataset di complessità crescente dimostra che il metodo fornisce una misura robusta ed efficiente, estendendo il ruolo della CT dall’ispezione geometrica alla caratterizzazione meccanica di materiali prodotti additivamente.The growing adoption of Additive Manufacturing (AM) for structurally and functionally demanding components has created the need for non-destructive techniques that assess not only internal geometry but also the mechanical response of complex materials. This work enables functional quality control of 3D-printed metamaterials through X-ray Computed Tomography (CT) without the use of artificial tracers or texture-enhancing particles. The thesis follows a structured progression: first, the state-of-the-art of CT-based deformation measurement is reviewed, highlighting the limitations of Digital Volume Correlation (DVC) and optical-flow methods when applied to engineered materials and AM components. Then, a dedicated procedure and new analysis algorithms are developed, specifically designed to operate on CT datasets inherently lacking artificial texture, avoiding seeding and ensuring compatibility with standard laboratory micro-CT systems. Finally, a comprehensive study of performance limits, accuracy, uncertainty, and sensitivity is conducted across controlled synthetic data and experimental case studies. The core contribution is a 2.5D deep optical-flow framework based on RAFT (Recurrent All-Pairs Field Transforms). Unloaded and loaded CT volumes are processed slice-wise along the three principal directions; on each slice RAFT estimates dense in-plane motion, yielding six directional volumetric fields. This slice-wise formulation preserves voxel-level resolution while avoiding the computational cost of full 3D correlation. Validation is carried out on five datasets of increasing complexity, including experimental benchmarks, synthetic ground-truth data, and noise-controlled CT acquisitions. Overall, the thesis presents a robust and computationally efficient method for CT-based volumetric deformation measurement, extending the role of CT from geometric inspection to full mechanical characterization of additively manufactured materials
Exploitation of sea fennel edible aerial parts for the manufacturing of innovative sea fennel-based foods
No full textQuesta tesi indaga il potenziale di valorizzazione del finocchio marino (Crithmum maritimum L.), sia della coltura sia dei suoi sottoprodotti, per lo sviluppo di alimenti fermentati e non fermentati incluse conserve vegetali, bevande, formulazioni spalmabili e di ingredienti funzionali. La caratterizzazione del kimchi (tradizionale preparazione fermentata coreana a base di ortaggi) arricchito con finocchio marino ha evidenziato che i prototipi fermentati mediante starter presentavano una rapida acidificazione, la dominanza dei batteri lattici e un profilo sensoriale stabile. Al contrario, i prototipi sottoposti a fermentazione spontanea hanno mostrato una maggiore diversità batterica, mentre le comunità fungine sono risultate simili tra le diverse tipologie, come confermato dalle analisi metatassonomiche. Il tempo di fermentazione, più che il tipo di prototipo, è emerso come il principale fattore in grado di influenzare significativamente la composizione dei composti volatili. I batteri lattici isolati dai prototipi fermentati spontaneamente sono stati ulteriormente caratterizzati per le loro attività enzimatiche, confermando tratti funzionali a supporto della prestazione fermentativa e dello sviluppo dell’aroma. Le parti aeree del finocchio marino sono state, inoltre, impiegate per la produzione di prototipi di sottaceti mediante fermentazione guidata da starter, seguita da acidificazione con aceto e trattamento termico moderato. Le formulazioni con acidità moderata hanno mantenuto sicurezza microbiologica, stabilità e aroma caratteristico per l’intero periodo di conservazione. I sottoprodotti del finocchio marino sono stati anche incorporati in birre a basso o nullo contenuto alcolico, fermentate con lieviti non convenzionali. Questi prototipi hanno mostrato performance fermentative differenziate, con produzione ridotta o assente di etanolo, e profili volatili arricchiti, incrementando la complessità aromatica delle bevande. L’incapsulamento in alginato degli estratti dei sottoprodotti, con o senza salamoia, ha preservato l’integrità strutturale e il contenuto di composti bioattivi, confermandone il potenziale come ingrediente funzionale. Infine, l’arricchimento di paté a base di olive con finocchio marino ha migliorato la stabilità ossidativa e il profilo aromatico durante lo stoccaggio. Nel complesso, i risultati dimostrano che il finocchio marino e i suoi sottoprodotti sono ingredienti tecnologicamente compatibili e versatili, capaci di favorire lo sviluppo di alimenti innovativi e sostenibili. This thesis investigates the potential valorization of sea fennel (Crithmum maritimum L.) crops and by-products for the development of fermented and non-fermented foods including vegetable preserves, beverages, and spreadable formulations and functional food ingredients. The characterization of sea fennel–enriched kimchi (a traditional Korean vegetable preserve) revealed that starter-driven prototypes showed rapid acidification, dominance of lactic acid bacteria, and a consistent sensory profile. In contrast, spontaneously fermented prototypes exhibited higher bacterial diversity, while fungal communities remained similar across both prototypes, as confirmed by metataxonomic analyses. Fermentation time, rather than prototype type, emerged as the main factor significantly affecting volatile composition. Lactic acid bacteria isolated from spontaneously fermented prototypes were further characterized for their enzymatic activities, confirming functional traits that support fermentation performance and aroma development. In addition, sea fennel aerial parts were used to produce pickle prototypes through starter-driven fermentation, followed by vinegar addition and mild heat treatment. Formulations with moderate acidity maintained microbial safety, stability, and characteristic aroma throughout storage. Sea fennel by-products were also incorporated into low- and non-alcoholic beers fermented with non-conventional yeasts, which exhibited differentiated fermentation performance, produced low or no ethanol, and generated enriched volatile profiles that enhanced beverage aromatic complexity. Alginate-based encapsulation of sea fennel by-product extracts, with or without recycled brine, preserved structural integrity and retained bioactive compounds, confirming their potential as functional ingredients. Finally, the enrichment of olive-based pâtés with sea fennel improved oxidative stability and aroma during storage. Overall, the results demonstrate that sea fennel and its by-products are technologically compatible and versatile ingredients that support the development of innovative and sustainable food products.
Essays on Sustainable Investing: From ESG Metrics to Portfolio Decisions and Investor Behavior
No full textLa presente Tesi di Dottorato, articolata in tre studi interconnessi, affronta le sfide fondamentali che emergono dall’integrazione della sostenibilità, intesa come ambientale, sociale e di governance, nel processo decisionale finanziario, superando il paradigma tradizionale rischio-rendimento. L’obiettivo centrale è contribuire al dibattito accademico e normativo (in particolare nell’ambito del quadro normativo MiFID II) analizzando come le preferenze di sostenibilità possano essere valutate, misurate e integrate operativamente nella selezione di portafoglio, ponendo l’accento sulla necessità di robustezza metodologica delle metriche ESG e sulla sfera comportamentale degli investitori.
Il primo studio fornisce una revisione critica e una sistematizzazione dei modelli di selezione di portafoglio, evidenziandone limiti e traiettorie di sviluppo future. Il secondo studio, attraverso un modello di selezione del portafoglio basato sulla programmazione per obiettivi (Goal Programming) ed un indicatore ESG armonizzato che penalizza il disaccordo tra i rating, mitiga la divergenza della performance di sostenibilità e produce risultati più stabili per gli investitori. Infine, il terzo studio dimostra che le preferenze di sostenibilità dichiarate non sono predittive del comportamento di investimento rivelato, sollevando un paradosso normativo: i questionari potrebbero suscitare risposte ambiziose che non corrispondono alle reali intenzioni comportamentali, sovrastimando la domanda effettiva di prodotti ESG.
Nel complesso, la tesi delinea un percorso di ricerca che parte dall’identificazione delle lacune teoriche e metodologiche, propone una soluzione quantitativa per affrontare l’incertezza dei dati ESG e conclude con la validazione empirica delle ipotesi comportamentali alla base del mercato. L’insieme dei risultati offre strumenti analitici ed evidenze empiriche utili a rendere gli investimenti sostenibili più efficaci, trasparenti e credibili.This Ph.D. Thesis, structured around three interrelated studies, addresses the fundamental challenges arising from the integration of sustainability, defined in its environmental, social, and governance dimensions, into financial decision-making, thus moving beyond the conventional risk-return paradigm. The central objective is to advance academic and regulatory debate (particularly within the MiFID II framework) by examining how sustainability preferences can be evaluated, quantified, and operationally integrated into portfolio selection processes.
The first study presents a critical review and synthesis of existing portfolio selection models, identifying their shortcomings and proposing future directions. The second study employs a Goal Programming (GP)-based portfolio selection model, integrating a harmonized ESG indicator that penalizes discrepancies among ratings. This approach reduces divergence in sustainability performance and delivers more stable outcomes for investors. The third study reveals that self-reported sustainability preferences are not reliable predictors of actual investment decisions, exposing a regulatory paradox: survey instruments may prompt aspirational responses that do not align with genuine behaviors, thus overstating real demand for ESG products.
Overall, this thesis maps a research journey that begins by identifying conceptual and methodological gaps, introduces a quantitative strategy to address ESG data uncertainty, and culminates in empirical validation of behavioral assumptions in the market context. Collectively, the findings offer analytical frameworks and empirical evidence to enhance the effectiveness, transparency, and credibility of sustainable investments
Balancing Technical, Human and Environmental Perspectives: A Model-Driven Development Framework for Stakeholder Inclusion
No full textNew and promising technologies constantly emerge. While they often show theoretical potential by defining high-value use cases, integrating them seamlessly into existing socio-technical ecosystems remains a significant challenge. This paper follows a Design Science Research approach to build a conceptual modeling-based framework to assesses how functional elements of new technologies align strategically with a set of technical, human, and environmental values. This approach is called the Model-Driven Framework for Security, Efficiency, Resiliency and Sustainability Value Alignment (MoDriSERSAl); it uses i* and Non-Functional Requirements (NFR) modeling tools to connect technical and human perspectives. The framework is materialized through a meta-model defining its concepts and a process fragment illustrating its application organization. We apply MoDriSERSAl to blockchain technology integration for Electronic Health Record (EHR) management to enable prioritization based on stakeholder inclusion (i.e. ensuring their needs and dependencies drive the integration process). MoDriSERSAl constitutes an effort towards stakeholder-based governance
Emerging Biomaterials for Maxillary Sinus Augmentation: From In Vitro Insights to In Vivo Clinical Translation
No full textMaxillary sinus augmentation is a key procedure for rehabilitating the atrophic poste-rior maxilla and enabling predictable implant-supported restorations. Although au-togenous bone remains the biological gold standard due to its superior osteogenic properties, its clinical use has declined because of donor-site morbidity, limited availa-bility, and increased operative time. Deproteinized bovine bone mineral (DBBM) is now the most widely used substitute, offering biocompatibility and long-term volumetric stability. However, as an inert osteoconductive scaffold with limited bioactivity and slow resorption, DBBM has stimulated interest in next-generation graft materials. Re-cent biomaterial innovations aim to enhance vascularization, accelerate osteogenesis, modulate immune responses, and achieve controlled resorption while preserving han-dling characteristics. These advances include ion-releasing bioactive ceramics, growth factor–enhanced allografts, polysaccharide–hydroxyapatite composites, smart hydro-gels, and synthetic scaffolds with tunable degradation. Because bone regeneration is highly complex, a robust translational framework integrating in vitro assays, animal models, and human clinical studies is essential. In vitro systems enable rapid cyto-compatibility and cell-interaction screening, while animal models provide insights into vascularization, immune behavior, and spatial bone formation. Human studies ulti-mately confirm clinical performance and implant success. This review synthesizes ev-idence from 2018 onward on emerging biomaterials for sinus floor elevation, evaluating their ability to overcome the limitations of DBBM and emphasizing the importance of a coordinated preclinical-to-clinical research continuum for safe and effective clinical translation
Nutritional care using oral nutritional supplements: 22 questions every clinician Asks—Answered by global experts in a Delphi consensus study
No full textBackground/aims: Malnutrition is a common clinical problem causing poor outcomes, including longer hospital stays, complications, functional decline, and mortality. Oral nutritional supplements (ONS) are a key component of medical nutrition therapy for patients who cannot meet their nutritional needs through diet alone. Despite their proven effectiveness, ONS use in practice remains inconsistent due to the lack of comprehensive, practice-based, and internationally validated guidelines. In 2023, the Turkish Clinical Enteral and Parenteral Nutrition Society (KEPAN) developed a national consensus report to address this gap. To enhance international validity and applicability, this study aimed to validate and refine those recommendations through a global Delphi process involving multidisciplinary experts. Methods: A two-round modified Delphi study was conducted between February 2023 and March 2024. Twenty-two experts from 13 countries and various disciplines (internal medicine, gastroenterology, geriatrics, surgery, family medicine, physiatry, clinical nutrition, dietetics, etc.) rated 22 predefined recommendations using a 5-point Likert scale. Consensus was defined as a median score >= 4 with a 25th percentile >= 4. Expert comments were reviewed and incorporated, and recent international guidelines were used to update the supporting commentaries as well. Results: Seventeen recommendations achieved consensus in round 1, and the remaining five in round 2. The final internationally validated set of recommendations covers practical aspects of ONS use including: (1) indications for initiation, dose, timing, and product selection; (2) monitoring strategies, adherence, and management of taste, tolerance, and other common problems; and (3) condition-specific considerations across diabetes, chronic kidney disease, cirrhosis, congestive heart failure, chronic obstructive pulmonary disease, neurological diseases, pressure injuries, surgery, cancer, geriatrics and multimorbidity, as well as guidance on continuation and discontinuation of ONS. The refined recommendations emphasize the food-first principle, individualized decision-making, and multidisciplinary collaboration to optimize person-centered nutritional care. Conclusions: This study delivers the first internationally validated, expert-informed recommendations on ONS use, providing a standardized and adaptable framework for global implementation. Familiarity with and application of these recommendations in clinical practice should lead to improved nutritional care, better adherence, enhanced patient outcomes, and more efficient, person-centered use of ONS across several healthcare settings. (c) 2025 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights are reserved, including those for text and data mining, AI training, and similar technologies
Traveling waves for highly degenerate and singular reaction-diffusion-advection equations with discontinuous coefficients
No full textSufficient conditions for either existence or non-existence of traveling wave solutions for a general quasi-linear reaction-diffusion-convection equation, possibly highly degenerate or singular, with discontinuous coefficients are furnished. Under an additional hypothesis on the convection term, the set of admissible wave speeds is characterized in terms of the minimum wave speed, which is estimated through a double-sided bound. (c) 2025 Elsevier Inc. All rights are reserved, including those for text and data mining, AI training, and similar technologies