DOCTORAL DEGREE IN ARCHITECTURAL DESIGN

• FERNANDEZ-MOSCOSO LOPEZ-DURAN, EDUARDO: La sustitución como recurso de proyecto. Hormigón armado y madera en la última etapa del Movimiento Moderno
  
  Author: FERNANDEZ-MOSCOSO LOPEZ-DURAN, EDUARDO
  Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
  Programme: DOCTORAL DEGREE IN ARCHITECTURAL DESIGN
  Department: Department of Architectural Design (PA)
  Mode: Normal
  Deposit date: 26/09/2025
  Reading date: 18/12/2025
  Reading time: 12:15
  Reading place: ETSAB (Escuela Técnica Superior de Arquitectura de Barcelona) - Planta Baja - Sala de GradosAv. Diagonal, 649-651 - 08028 - Barcelona
  Thesis director: PEÑIN LLOBELL, ALBERTO | FERRATER ARQUER, BORJA
  Thesis abstract: The thesis begins with a critical observation: the substitution of materials in architecture without altering the original constructive logic, as seen in Doric temples rebuilt in stone or in Sverre Fehn’s Nordic Pavilion. This practice challenges the idea that each material must be used strictly according to its physical properties. The author proposes a critical suspension of this paradigm, inspired by Husserl, in order to open architectural design to a more experimental and symbolic logic.From an interdisciplinary perspective that combines technique, history, theory, and philosophy, the thesis argues that technique is not only functional but also narrative. Concepts such as *design hysteresis* or *formwork as material memory* show how technical operations can also be interpretative. Moreover, the use of contemporary materials like CLT (Cross Laminated Timber) allows substitution to be approached from a sustainability perspective.Four historical milestones are analyzed: Greek temples, Norwegian stave churches, the Ironbridge, and the Hennebique system. In all of these cases, substitution not only preserved the architectural form but also opened up new technical and expressive possibilities. The analysis of authors such as Vitruvius, Wright, Nervi, and Arup reveals that even the most normative discourses have allowed for adjustments and material reinterpretations.The second part of the thesis examines three contemporary case studies. In the Tremaine House, Neutra replaces wood with concrete to redefine the relationship between house and landscape. In the Kagawa Prefectural Offices, Tange substitutes traditional wooden structures with reinforced concrete while preserving the formal logic of Japanese architecture. In the Nordic Pavilion, Fehn uses concrete as if it were wood, creating a hybrid architecture between tradition and modernity.The thesis concludes that substitution is a valid architectural operation capable of enriching the project from technical, symbolic, and cultural standpoints. Introducing alternative materials does not weaken a work; rather, it expands its meaning. Furthermore, it is proposed that technique should be understood as an open and narrative process, and that substituting materials is not a denial of their origin but a projection of new interpretations.Finally, the thesis invites further exploration of substitution involving other material pairings, prefabrication processes, and even immaterial elements such as typologies or programs, thereby opening new lines of research within contemporary architectural design.
  

DOCTORAL DEGREE IN ARTIFICIAL INTELLIGENCE

• GONZÁLEZ GUTIÉRREZ, CÉSAR: Analyzing and Leveraging the Structure of Pre-trained Embeddings
  
  Author: GONZÁLEZ GUTIÉRREZ, CÉSAR
  Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
  Programme: DOCTORAL DEGREE IN ARTIFICIAL INTELLIGENCE
  Department: Department of Computer Science (CS)
  Mode: Normal
  Deposit date: 27/11/2025
  Reading date: pending
  Reading time: pending
  Reading place: pending
  Thesis director: QUATTONI, ARIADNA JULIETA
  Thesis abstract: Developing models with limited annotation budgets (few-shot learning) is of great importance due to the high costs associated with data annotation.Recent advances in text classification have demonstrated that representations derived from pre-trained language models play a crucial role, especially in few-shot learning settings. These new advancements raise two natural questions:1) What properties of pre-trained representations can explain their effectiveness in few-shot learning?, and2) Can we leverage these properties to further enhance performance under limited annotation conditions? In the first part of this work, we address the first question and show that the effectiveness of pre-trained representations in few-shot scenarios can be explained by the degree of alignment between supervised task labels and the hierarchical structure of the pre-trained embedding space. In the second part, we propose a label propagation method designed to exploit this alignment, leading to improved performance in few-shot classification tasks.
  

DOCTORAL DEGREE IN CHEMICAL PROCESS ENGINEERING

• ESPEJO DELGADO, VICENÇ: Analysis and modelling of explosions in gas-fired combustion chambers
  
  Author: ESPEJO DELGADO, VICENÇ
  Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
  Programme: DOCTORAL DEGREE IN CHEMICAL PROCESS ENGINEERING
  Department: Department of Chemical Engineering (EQ)
  Mode: Normal
  Deposit date: 28/10/2025
  Reading date: 17/12/2025
  Reading time: 11:30
  Reading place: Escola d'Enginyeria de Barcelona Est (EEBE) Edifici A - Aula A0.02 Campus Diagonal-Besòs (CDB) https://eebe.upc.edu/ca/lescola/com-arribar
  Thesis director: CASAL FABREGA, JOAQUIM | PLANAS CUCHI, EULALIA
  Thesis abstract: Combustion chambers are a common equipment widely used in many industries to retrieve heat from fuels (such as in boilers, furnaces, and other fired heaters). Despite the well-documented explosion hazards associated with this equipment, accidents continue to be reported periodically in the industry. The consequences of such events can be catastrophic, leading to severe damages to the equipment, surrounding structures or other equipment, as well as injuries or fatalities.This thesis focusses on the study combustion chamber gas-fired explosion scenarios as a result of the accumulation of unburned gas inside the firebox until flammable conditions are reached, and ignition occurs. As an initial step, a historical analysis of accidents was conducted to typical accident sequences and to highlight the importance of different contributing causes. The main objective of the work is therefore to study these scenarios and provide insights that may improve safety protection design, risk assessments and engineering practices for gas-fired combustion chambers in industrial applications.Some experimental work was found during bibliographic research for similar geometry enclosures, but limited in size, up to 64 m3. However, industrial combustion chambers can reach volumes of thousands of cubic meters. Full-scale experimentation on such equipment would be costly and would require extensive infrastructure to contain, isolate and monitor the explosions. As an alternative, this research employs simulations with FLACS, a Computational Fluid Dynamics (CFD) software widely validated for explosion scenarios, to study the considered explosion cases.The effects of explosions and their dependence on combustion chamber geometry characteristics were evaluated taking special attention on the influence of explosion panels, internal elements, chamber size, as well as the fuel used in explosion development and maximum peak pressures reached. To assess the external effects on the surroundings, an adaptation of the TNT-equivalency model was developed, providing a method to adjust the model yield factor to the combustion chamber explosion consequences.Finally, fuel dispersion inside the chamber was simulated to characterize how unburned fuel evolves over time when introduced through burners. These scenarios were related with the explosion sequences identified in the historical accident analysis. The influence of furnace duty, fuel premixing with air, and burner configuration (single vs. multiple burners) was investigated. Ignition of the accumulated fuel at different dispersion times resulted in explosions with different fuel amounts and concentrations and was also assessed to capture the impact of explosion onset at different stages of scenario evolution. The outcomes of this thesis highlight the effect of key combustion chambers characteristics on explosion phenomena. The evolution of the scenarios identified a critical “trend shift” period, that corresponded to the the timeframe to reach hazardous concentrations. Sensitivity analyses considering different fuels, air pre-mixing, burner configurations or maximum duty per chamber volume revealed general trends applicable to other combustion chamber designs. Overall, the findings provide valuable insights into explosion phenomena in combustion chambers, and offer practical guidance for safer systems design, as well as safeguards effectiveness criteria to be considered in risk assessments.
  

DOCTORAL DEGREE IN COMPUTATIONAL AND APPLIED PHYSICS

• CONESA ORTEGA, DAVID: Empirical and Structural Mathematical Models for Biological Systems: Case Studies in COVID-19 and Cardiac Dynamics
  
  Author: CONESA ORTEGA, DAVID
  Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
  Programme: DOCTORAL DEGREE IN COMPUTATIONAL AND APPLIED PHYSICS
  Department: Department of Physics (FIS)
  Mode: Normal
  Deposit date: 21/10/2025
  Reading date: 18/12/2025
  Reading time: 11:00
  Reading place: Sala de graus de l'EPSEB
  Thesis director: ALVAREZ LACALLE, ENRIQUE
  Thesis abstract: In the diverse and complex world we live in, we ask ourselves how everything that surround us works. We aim to understand what, how, why, when, and, in this context, scientists started to use mathematical language to model and explain the events of this world. Biology encompasses many different topics, with multiple scales, and the types of models used for their study vary from one to the other.In this thesis we elaborate empirical and predictive mathematical models, mechanistic models as well, to study and analyze two branches of biology: epidemiology, in the context of a pandemic like COVID-19, and cardiac dynamics.To start, we develop predictive, Gompertz-like models to predict two weeks in advance the increase of the incidence of COVID-19, based on country-level reported data from WHO. In this chapter, we analyze the reliability and accuracy of such models with different processing to correct certain patterns due to possible inconsistencies in the daily reports during the most tense times of the pandemic.Continuing with epidemiology, in this thesis we also perform a study of correlation between incidence of COVID-19 in the Spanish society, province by province, and mobility data from different sources: the Spanish Ministry of Transport and Mobility and Facebook Data For Good. Using tools like the Principal Component Analysis, we determine what data correlate the most with incidence, either workdays or weekends mobility, or temperature or humidity. Results indicate that mobility is either directly causal or it is highly, directly correlated with other measures that affect propagation, whereas meteorological patterns seem less relevant by themselves.Turning to cardiac dynamics, this thesis has a focus on the development of computational models aiming to study calcium dynamics in cardiomyocytes for its future analysis in relationship to cardiac diseases. On the one hand, we develop a model of rabbit atria mixing two models: one developed previously by the same author focused on the spatial dynamics of calcium, and one developed by Holmes focused on ionic currents in the membrane. During the process, using a population-of-models approach, we determine some unknown parameters for the RyR2, NCX and SERCA currents that give rise to models behaving like experimental data usually observed. Moreover, during the process, we get diverse groups of models with different behaviors between them, useful to study cells in conditions more susceptible to disease.Last but not least, we develop another model at submicron scale to analyze how calcium waves originate and what type. In particular, we study scenarios where calsequestrin is either colocalized or it is not with RyR2, or how inactivation of RyR2 by calmodulin affects wave propagation. The study unveils that colocalization is key and vital for wave propagation. Inactivation of RyR2 by calmodulin allows the wave to travel more rapidly and hinders the appearance of another equilibrium state with an excessive calcium in the cytosol and low calcium load in the sarcoplasmic reticulum.To conclude, this thesis contributes to the study of two completely different fields in biology from the point of view of different mathematical models, always with the aim to understand and prevent causes leading to disease.
  
• MIRZAY SHAHIM, MAAHIN: Catalytic Properties of Amorphous Alloys
  
  Author: MIRZAY SHAHIM, MAAHIN
  Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
  Programme: DOCTORAL DEGREE IN COMPUTATIONAL AND APPLIED PHYSICS
  Department: Department of Physics (FIS)
  Mode: Normal
  Deposit date: 17/11/2025
  Reading date: 16/12/2025
  Reading time: 15:00
  Reading place: Sala Polivalent, Edifici I planta 0, espai I.0.1, EEBE Campus Besós
  Thesis director: PINEDA SOLER, ELOY | SOLER TURU, LLUIS
  Thesis abstract: This thesis explores the catalytic potential of metallic glasses (MGs) and their combination with cerium oxide (CeO₂) for low-temperature carbon monoxide (CO) oxidation and CO preferential oxidation (COPrOx) reactions. Metallic glasses, due to their non-crystalline structure and tunable composition, offer a promising platform for catalytic applications when appropriately engineered. The study focuses on three primary MG systems: Ce65Al35, Pd77Si16.5Cu6.5, and Cu48Zr48Al4, examining their structural characteristics, and catalytic behavior. The results showed that the Ce65Al35 metallic glass has limited catalytic activity, even after various activation treatments such as ball milling, calcination, or combination with CeO2. However, doping the binary Ce-Al system with Pd (Ce61Al35Pd4) markedly improved performance, achieving 100% CO conversion at 300°C when ball milled. Interestingly, mixing this ternary MG with CeO₂ did not provide further enhancement, indicating that Pd’s role is dominant and not synergistic with ceria. The Pd77Si16.5Cu6.5 MG emerged as the most effective standalone catalyst, delivering full CO conversion at only 240°C. Which could be attributed to Pd and its optimized distribution in the amorphous matrix. Control experiments with binary alloys (Pd77Si23 and Cu6Si94) highlighted the importance of both composition and structural processing, particularly the necessity of melt spinning and ball milling to generate active, fine-particle structures.Another major contribution of this work is the development and detailed characterization of Cu-based MG/CeO2 composites, especially Cu48Zr48Al4.These systems showed strong activity and stability in both CO and COPrOx reactions, with performance enhanced through ball milling. Structural and operando analyses (XPS, EXAFS, NEXAFS, and XRD) confirmed that the catalysts undergo surface rearrangement during reaction, stabilizing catalytically active Cu(I) atoms. A spontaneous aging phenomenon and a similar change under hydrogen pre-reduction pointed to the dynamic evolution of active sites during real operation conditions. This study demonstrates that mechanochemical synthesis and careful structural design of MG/CeO₂ composites enable the development of efficient, low-cost, and stable oxidation catalysts. These findings offer new strategies for creating highly active materials for pollution control and hydrogen purification technologies, opening the path to use amorphous metals for heterogeneous catalysis.
  

DOCTORAL DEGREE IN COMPUTER ARCHITECTURE

• ALLKA, XHENSILDA: Enhancing Data Quality in IoT Monitoring Sensor Networks
  
  Author: ALLKA, XHENSILDA
  Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
  Programme: DOCTORAL DEGREE IN COMPUTER ARCHITECTURE
  Department: Department of Computer Architecture (DAC)
  Mode: Normal
  Deposit date: 31/10/2025
  Reading date: 30/01/2026
  Reading time: 11:00
  Reading place: Sala C6-E101
  Thesis director: BARCELÓ ORDINAS, JOSE MARIA | GARCÍA VIDAL, JORGE
  Thesis abstract: In recent years, technological development and an increased number of cars among other factors, have influenced air pollution levels. This increase in levels has also increased the need to monitor them, as they are directly related to human health and the economy. To monitor air pollution, the government has deployed precise monitoring stations, which are expensive to deploy and maintain. Due to their cost, they are not widely distributed. However, since air pollution can change over short distances, the distribution of these stations can be insufficient. Recently, a solution has emerged: the use of low-cost sensors (LCSs), which provide broader coverage at a much lower cost. However, these LCSs have one drawback: the quality of the data they provide is poor.Current research in this field has employed machine learning (ML) models to calibrate these LCSs, thereby enhancing the quality of the data they provide. In an Internet of Things (IoT) monitoring network, the quality of data is closely associated with decision-making processes. This thesis focuses on enhancing the data quality provided by the LCSs from two perspectives: improving calibration performance and detecting anomalies and outliers. The objective of both of these perspectives is to ensure data accuracy and reliability.The first part of the thesis focuses on the improvement of the calibrated data provided by the LCSs and the detection of the concept drift and the update of the parameters of the current calibration model such that it adapts to the new conditions. We are enhancing the quality of the calibrated data by implementing a model pattern-based approach. Our proposed methods, Temporal Pattern Based Denoising (TPB-D) and Temporal Pattern Based Calibration (TPB-C), improve the quality of the calibrated data. Given that environmental conditions are subject to change over time, it is essential to update the parameters of the calibration model. We proposed Window-based Uncertainty Drift Detection and Recalibration (W-UDDR), a system capable of detecting the presence of concept drift (i.e., environmental changes).The second part of the thesis focuses on the reliability of the data. Sensors, regardless of their cost, are often prone to irregularities such as outliers, anomalies, or drift, which can be caused by various factors. It is critical to identify these irregularities, as the data will be incorporated into the training of the model related to other tasks. In this thesis, three distinct scenarios were examined. The first one is related to the detection of outliers in the edge. In this case, we proposed the Edge Streaming Outlier Detection (ESOD) framework. ESOD is a simple and lightweight framework that can identify outliers in the edge with a limited amount of memory. The system offers two approaches: real-time and near real-time. The near real-time approach involves minor delays in decision-making. The second approach is related to the detection of more complex irregularities, such as anomalies in a given sensor. This scenario is distinct from the first one in that it offers offline anomaly detection capabilities. We proposed spatiotemporal correlation recurrent autoencoder anomaly detection (STC-RAAD), which demonstrated satisfactory performance in detecting anomalies in a given sensor. It is worth noting that the third scenario pertains to the detection and localization of anomalies in a network of sensors. This is of particular relevance in scenarios where the identification and precise location of the source of an anomaly are crucial. We hereby propose a pattern-based attention recurrent autoencoder anomaly detection (PARAAD) method. This method is designed to detect and localize anomalies in sensors.
  
• BANCHELLI GRACIA, FABIO FRANCISCO: Evaluation and methods to increase efficiency of HPC systems with different maturity levels
  
  Author: BANCHELLI GRACIA, FABIO FRANCISCO
  Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
  Programme: DOCTORAL DEGREE IN COMPUTER ARCHITECTURE
  Department: Department of Computer Architecture (DAC)
  Mode: Normal
  Deposit date: 12/11/2025
  Reading date: 18/12/2025
  Reading time: 10:00
  Reading place: C6-E106
  Thesis director: MANTOVANI, FILIPPO | GARCIA GASULLA, MARTA
  Thesis abstract: High-Performance Computing (HPC) has entered an era of increasing architectural diversity and complexity, with systems ranging from experimental prototypes to large-scale production machines. This evolution presents a fundamental challenge: how to consistently evaluate performance, scalability, and efficiency across platforms with varying levels of technological maturity. Traditional benchmarking methods, while effective for fully deployed systems, often fall short when applied to early-stage prototypes where software stacks are incomplete or hardware is still under development.This thesis proposes and develops a comprehensive evaluation methodology capable of addressing these challenges. The approach gives a multi-layered perspective on performance, and it is structured around three complementary levels: micro-benchmarks, standard HPC benchmarks, and full scientific applications. Technology Readiness Levels (TRLs) are introduced as a guiding concept, allowing the methodology to be adapted according to the maturity of the system under study. At high TRL, the methodology enables comparative assessments of production supercomputers, while at low TRL, it helps identify bottlenecks and optimization opportunities early in the design cycle.The thesis contributes both conceptual and practical tools. It formalizes performance and efficiency models (including Roofline, Top-Down, and efficiency metrics) and demonstrates their use across multiple architectures. It further extends tracing and monitoring capabilities for emerging processors, introduces methods to access and interpret hardware counters on novel architectures such as \riscv, and evaluates the integration of experimental hardware through Software Development Vehicles (SDVs) and FPGA-based emulation. These tools are validated through case studies on production systems, such as the MareNostrum 5 supercomputer and other HPC clusters deployed at the Barcelona Supercomputing Center (BSC), as well as on prototypes from European projects, such as EPAC.Results show that the proposed methodology provides actionable insights at all maturity levels: from guiding hardware-software co-design in early-stage processors to enabling reproducible performance comparisons across pre-exascale systems. Beyond benchmarking, it provides valuable feedback for hardware architects, system software developers, and application scientists alike. By bridging the gap between low-TRL prototypes and production-ready HPC systems, this work contributes to building a consistent framework for evaluating and improving the efficiency of future European and global supercomputers.
  
• BARRERA HERRERA, JAVIER ENRIQUE: Improving Time Predictability and Code Coverage of Embedded GPUs for Real-Time Systems
  
  Author: BARRERA HERRERA, JAVIER ENRIQUE
  Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
  Programme: DOCTORAL DEGREE IN COMPUTER ARCHITECTURE
  Department: Department of Computer Architecture (DAC)
  Mode: Normal
  Deposit date: 07/11/2025
  Reading date: 23/01/2026
  Reading time: 11:00
  Reading place: C6-E101
  Thesis director: CAZORLA ALMEIDA, FRANCISCO JAVIER | KOSMIDIS, LEONIDAS
  Thesis abstract: This dissertation addresses challenges that the adoption of GPUs in Critical Embedded Systems (CES) faces, namely, Time Predictability and Code Coverage. Different domains that deploy CES are constantly adding Artificial Intelligence (AI)-based features, such as autonomous driving, that demand high performance levels. Multi-Processors Sytem-on-Chip (MPSoCs) are widely used to provide said performance levels, as they are equipped with accelerators, among which, Graphics Processing Units (GPUs) are a common choice. However, CES must undergo a rigorous Verification and Validation (V&V) process, in which a certain level of Execution Time Determinism (ETD) must be guaranteed. The use of several tasks to increase the overall utilization introduces contention in shared resources, which induces time variability. To provide the ETD guarantees, the time variability must be either mitigated or tracked and controlled. Another challenge for the adoption of GPUs in CES, is that the V&V process demands evidence of the thoroughness of the testing phase, for which Code Coverage is used as a test quality indicator. However, Code Coverage, as traditionally understood for sequential CES does not cover all possible scenarios in which a GPU thread might execute.For low-criticality and mixed-criticality CES, we contend that we can allow tasks to share the Last Level Cache (LLC) if hardware support for contention tracking is provided. Providing a clear understanding on how tasks contend with each other enables CES developers to balance performance and time predictability. For high-criticality CES, it is a common practice to implement LLC partitioning as it allows tasks to access LLC without suffering from inter-kernel contention, however, tasks may experience a performance loss due to lack of resources. In this Thesis, we propose Demotion Counters, a novel technique that tightly tracks how much each task has been demoted towards eviction in the LLC, thus, effectively quantifying their impact in CES. Additionally, we also assess the use of NVIDIA’s Multi-Instance GPU (MIG) feature as means to improve ETD in high-criticality CES.Code Coverage is used as a test quality indicator to provide evidence of the thoroughness of the testing, as required by the V&V process. However, if applied as traditionally understood, it will ignore the threading dimension of GPUs. Threads have private regions of memory, as well as shared regions at different granularities. This means that errors that are innocuous to one thread are potentially harmful for another, hence, it does not cover all possible cases under which GPU threads might execute. In this Thesis, we propose the use of Per-Thread Statement Coverage (PTSC), which tracks the Code Coverage at thread granularity. In order to mitigate the overheads caused by PTSC, several variants that apply different orthogonal optimizations are also proposed. Finally, we also evaluate the potential benefits of using hardware support for PTSC, mitigating the memory consumption of PTSC, as well as the execution time impact at deployment.Summarizing, this Thesis advances the state of the art in the adoption of GPUs in CES. The proposal of hardware contention tracking support and assessment of NVIDIA’s MIG, as means to improve ETD, effectively tackles the Time Predictability challenge in shared LLC. The proposal of software PTSC allows providing CES designers with the whole picture of the execution in commercially available GPUs. The use of hardware support for PTSC mitigates the overheads of software PTSC in deployment, while the different compression techniques reduce the volume of information during testing phase without losing data. Therefore, this Thesis provides means to face the Time Predictability and Code Coverage challenges of GPUs in CES.
  
• GIESEN LEÓN, JEREMY JENS: Modeling and Optimization of Timing Interference for Time Critical Systems on Multicore COTS Platforms
  
  Author: GIESEN LEÓN, JEREMY JENS
  Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
  Programme: DOCTORAL DEGREE IN COMPUTER ARCHITECTURE
  Department: Department of Computer Architecture (DAC)
  Mode: Normal
  Deposit date: 27/11/2025
  Reading date: pending
  Reading time: pending
  Reading place: pending
  Thesis director: MEZZETTI, ENRICO | CAZORLA ALMEIDA, FRANCISCO JAVIER
  Thesis abstract: Critical Real-Time Embedded Systems (CRTES) underpin automotive, aerospace, medical devices, among others. They must guarantee deterministic, certifiable behavior under worst-case conditions. As functionality grows (sensor fusion, AI, etc), uniprocessors fall short, prompting adoption of COTS multicores. Yet shared resources induce timing interference that threatens predictability and complicates certification, especially in heterogeneous SoCs with crossbars, bridges, and hierarchical memory.This Thesis advances timing predictability on complex multicores through three linked pillars: standardized hardware observability, contention modeling, and system-level optimization. Together they form a coherent, auditable path from low-level measurements to design decisions.First, we introduce unified observability frameworks combining core-local counters with system-level tracing. They correlate hardware events with task phases, reconstruct scheduling and contention across cores and interconnects, and standardize configuration and interpretation across heterogeneous devices. Measurements are attributed to tasks (excluding OS activity), incur bounded overhead, and yield ordered access sequences preserving temporal structure. Along with latency tables for memories and bridges, these artifacts make timing phenomena measurable and calibrate conservative models.Second, we develop contention models grounded in realistic traces. Traditional Access-Count Contention Techniques (ACCT) are overly conservative for parallel crossbars. Sequence-Aware Techniques (SACT) exploit request ordering to prune infeasible overlaps and tighten bounds. We propose ASCOM, a scalable framework balancing accuracy through compositional pairing against contender sequences and segmentation of long traces. We derive explicit upper/lower bounds to quantify margins and add bridge awareness to capture inter-cluster traversals and remote-memory asymmetries. Across single- and multi-crossbar SoCs, sequence-aware analysis yields tighter, trustworthy bounds while remaining tractable on industrial-scale traces.Third, we examine how modeling informs code and data placement across heterogeneous memories. Feasibility considers capacity and compatibility; locality and non-uniform latencies are captured through calibrated SACT. Exploration reveals pronounced sensitivity to placement: with identical workloads and schedules, changing only the mapping can shift contention by over 100% of reference execution time, due to bridge traversals, device asymmetries, and port effects. Architectural factors thus directly shape worst-case interference, elevating placement to a first-order design parameter.An end-to-end workflow operationalizes these ideas. System-level traces are captured on an industrial target hardware. Traces are filtered into ordered access sequences retaining temporal structure and feeding SACT analysis. Empirical campaigns build latency tables for memories and bridges. With these calibrated inputs, the bridge-aware SACT model estimates contention and total delay for alternative placements.Results show robust contention analysis on COTS multicores is feasible when: (i) the right signals are observed with standardized, low-intrusion instrumentation; (ii) models are sequence- and bridge-aware with explicit margins; and (iii) insights drive placement where locality and capacity are addressed coherently. Because ordered sequences, latency tables, and task-scoped metrics come from the deployed hardware, conclusions are auditable and fit safety cases. Combining hardware-aware instrumentation, realistic modeling, and contention-driven mapping, the Thesis provides a practical framework for timing predictability in CRTES and narrows the gap between certification expectations: traceability, explainability, repeatability and the behavior of parallel interconnects and heterogeneous memories in contemporary multicore SoCs.
  

DOCTORAL DEGREE IN CONSTRUCTION ENGINEERING

• RAMIREZ PEREZ, ALEXIS JOHARIV: Comportamiento a flexión y cortante de un tablero continuo de vigas pretensadas con tendones de polímeros reforzados con fibras (FRP)
  
  Author: RAMIREZ PEREZ, ALEXIS JOHARIV
  Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
  Programme: DOCTORAL DEGREE IN CONSTRUCTION ENGINEERING
  Department: Department of Civil and Environmental Engineering (DECA)
  Mode: Normal
  Deposit date: 22/10/2025
  Reading date: 12/01/2026
  Reading time: 11:00
  Reading place: C1-002
  Thesis director: OLLER IBARS, EVA MARIA | MARI BERNAT, ANTONIO RICARDO
  Thesis abstract: The durability of reinforced concrete structures is mainly compromised by steel corrosion, which generates high maintenance costs and reduces structural safety. Fiber-reinforced polymers (FRP) represent an alternative of great interest, as they provide high specific strength and are not susceptible to corrosion. However, their application as active reinforcement in continuous prestressed members is still very limited, due to the scarce experimental research on their structural performance and the absence of specific design guidelines.The main objective of this dissertation is to analyze the flexural and shear behavior of a two-span continuous bridge at 1/3 scale, built with precast prestressed girders and a cast in situ reinforced concrete slab, using carbon carbon fiber composite cables “CFCC” tendons as active reinforcement. The research was organized into three phases: (1) characterization of carbon fiber (CFRP) bars, glass fiber (GFRP) bars, and CFCC tendons, with the latter selected for prestressing due to their suitability; (2) a flexural test on span 1, with a concentrated load applied at midspan, to study the global flexural behavior at the serviceability and ultimate limit states; and (3) a shear test on span 2, with a concentrated load applied 1.6 m from the end support, to evaluate shear strength, effectiveness of GFRP stirrups, and the influence of CFCC prestressing. The results were compared with numerical simulations using the CONS program and with the CCCM analytical model adapted to FRP tendons. The experimental tests showed that CFCC tendons reached 62–76% of their ultimate strength without anchorage slip in the flexural test, confirming their reliability as active reinforcement. Failure was governed by shear-off at the girder–slab interface. In shear, failure occurred after a characteristic diagonal cracking pattern and progressive redistribution of stresses between spans, while shear-off failure was avoided through a reinforcement added after the flexural test.The overall contribution of this dissertation lies in providing the first comprehensive experimental, analytical, and numerical evidence on a continuous bridge prestressed with CFCC tendons. The findings strengthen confidence in the use of FRP in concrete structures, and open new research avenues aimed at optimizing transverse reinforcement and moving towards the codification of this technology.
  
• ROYANO GARCIA, VERÓNICA: A Function-Oriented Assessment Methodology (FOAM) for life-cycle monitoring of building functional condition
  
  Author: ROYANO GARCIA, VERÓNICA
  Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
  Programme: DOCTORAL DEGREE IN CONSTRUCTION ENGINEERING
  Department: Department of Civil and Environmental Engineering (DECA)
  Mode: Normal
  Deposit date: 27/11/2025
  Reading date: pending
  Reading time: pending
  Reading place: pending
  Thesis director: SERRAT PIE, CARLES | RAPINSKI, JACEK TOMASZ
  Thesis abstract: The effective management of the aging building stock is currently hindered by two critical gaps: the lack of a standardized common language for data exchange and the limitations of existing assessment paradigms. Current methodologies prove insufficient: defect-based approaches prioritize physical integrity over the direct evaluation of functional condition, while serviceability models rely on variable, context-dependent user requirements. These limitations render current approaches unsuitable for objective, longitudinal analysis of functional performance. To address these challenges, this doctoral thesis presents the development and validation of the Function-Oriented Assessment Methodology (FOAM), a comprehensive framework designed for the objective, life-cycle monitoring of the functional condition of construction elements.The methodology is established upon four fundamental contributions: (i) adopting the international ISO/IEC 81346 standard to ensure rigorous and interoperable element classification; (ii) conceptualizing the Element-Function (E-F) network, a hierarchical structure that links construction elements to their functions and defines the aggregation weights; (iii) operationalizing data collection through the Functional Condition Assessment Questionnaire (FCAQ), enabling the transformation of subjective inspections into standardized discrete data; and (iv) developing a mathematical engine that translates these data into a continuous, time-dependent Functional Condition Index (FCI).The statistical behavior of the proposed estimator, (FCI) ̂(t), has been rigorously validated through a comprehensive in silico simulation study comprising 2,187 scenarios modeled using a Generalized Estimating Equations (GEE) approach. The results demonstrate that the estimator is statistically sound, confirming its unbiased nature and √n-consistency. A critical finding of the sensitivity analysis is that the methodology is highly robust to random inspector variability but extremely sensitive to systematic inspector bias. This establishes that unbiased inspection protocols are a non-negotiable prerequisite for reliable estimation. Furthermore, the analysis identifies the functional degradation pattern and the evaluation time as the dominant factors influencing the predictive capacity of the model.Beyond theoretical validation, the practical applicability of the framework has been demonstrated through the development of the FastFoam web platform, achieving a Technology Readiness Level (TRL) 7. This thesis concludes that FOAM resolves the assessment paradigm, overcoming subjective, defect-based approaches towards an objective, function-based methodology, providing a robust tool to support well-informed decision-making in asset management and the long-term preservation of the built environment.
  
• VALVERDE BURNEO, DAVID ENRIQUE: Desarrollo de nuevos materiales cementicios multifuncionales
  
  Author: VALVERDE BURNEO, DAVID ENRIQUE
  Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
  Programme: DOCTORAL DEGREE IN CONSTRUCTION ENGINEERING
  Department: Department of Civil and Environmental Engineering (DECA)
  Mode: Article-based thesis
  Deposit date: 10/10/2025
  Reading date: 19/01/2026
  Reading time: 11:00
  Reading place: C1-002
  Thesis director: SEGURA PEREZ, IGNACIO | GARCIA TRONCOSO, NATIVIDAD LEONOR
  Thesis abstract: This doctoral thesis focuses on the development of multifunctional cementitious materials, combining structural strength with self-sensing capabilities through piezoresistivity, as well as integrating deformation energy dissipation through auxetic structures. The research explores the integration of conductive and structural fibers in cementitious matrices, coupled with the use of advanced manufacturing techniques such as 3D printing and the use of flexible silicones to obtain molds with complex architectures. The objective is to obtain cementitious materials that in addition to possessing structural capacity, have added function capabilities. It is expected that these materials can be used in buildings with self-monitoring, damage prevention, stress sensing pavements, structural elements with higher impact resistance and energy dissipation capabilities. The research begins with an exhaustive bibliographic review, from which the most promising materials have been selected to achieve the proposed objectives. The experimental campaign and data treatment/analysis have been defined. The work continues with the realization of the planned experiments, the analysis of the results, the optimization of the composition and properties of the new cementitious materials, the development of prototypes testing the potential applications.From the achievements obtained in this doctoral thesis we have the following: the research and publication of a cementitious composite reinforced with recycled carbon fibers to obtain a piezoresistive conductive concrete, which presents a variation of the electrical conductivity with respect to the unitary deformation quite evident when the fiber addition contents are around 1% in volume. This makes it an ideal sustainable cementitious material for strain and/or stress detection. This publication can be found in the journal Construction and Building Materials.Another research focuses on the mechanical characterization of cellular auxetic cementitious cementitious composites (which achieve their auxeticity through the presence of ellipsoidal holes in their structure) reinforced with recycled steel fibers. This research successfully characterizes the influence of fiber content on the mechanical response to compression and deformation energy dissipation, while demonstrating the feasibility of using recycled resources. Within this same publication, a family of functions was presented that successfully fit the mechanical response curves (stress-strain, energy dissipated by deformation) that were obtained experimentally. This publication can be found in the Journal of Building Engineering.A third article achieved in this thesis deals with the development of a new type of piezoresistive concrete with auxetic capacity. This material, obtained by combining cellular auxetic cementitious cementitious composites and recycled carbon fibers, is capable of detecting deformations from very low to high levels. Its potential applications in structural monitoring are promising, and the results of this research have been published in Case Studies in Construction Materials.
  
• XIE, JIACHONG: Study on the long-term mechanical behaviour of segmental tunnel-ground system under localised leakage
  
  Author: XIE, JIACHONG
  Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
  Programme: DOCTORAL DEGREE IN CONSTRUCTION ENGINEERING
  Department: Department of Civil and Environmental Engineering (DECA)
  Mode: Change of supervisor + Article-based thesis
  Deposit date: 24/11/2025
  Reading date: 16/12/2025
  Reading time: 08:00
  Reading place: Tongji University, China
  Thesis director: MOLINS BORRELL, CLIMENT
  Thesis abstract: Leakage defects are one of the main problems in present-day segmental tunnels, primarily occurring at gasketed joints. Over the long term, the leakage can cause ground movement, lining settlement and deformation, thereby threatening the operational safety of the tunnel. Furthermore, the bidirectional leakage phenomenon often observed in pressurised segmental tunnels further complicates the mechanisms of leakage-induced soil-tunnel interaction.This thesis focuses on the leakage problem in segmental tunnels and its associated geotechnical-structural consequences, and offers useful tools for predicting the long-term sealant performance of joints, identifying the localised leakage behaviour, and assessing the leakage impact on the tunnel-ground system. The primary work carried out in this thesis is summarised as follows:The study begins by developing a theoretical model to evaluate the waterproof capacity of gasketed joints affected by joint deformation, implementing multi-scale contact and percolation theories to capture the adverse effect of gasket surface roughness. This model is further extended to predict the long-term sealant performance throughout the operational period, incorporating the time-dependent behaviours of gasket rubber. Then, to characterise the localised leakage behaviour of gasketed joints, a novel pathfinding algorithm-based approach is proposed, which treats the gasket interface as the search space, simultaneously obtaining the optimal leakage path and the waterproof capacity under different joint deformations. This approach identifies the distinct sealant mechanisms of continuous and T-joints.To address the leakage-induced soil-tunnel interaction problem, an initial investigation is conducted under an unfavourable scenario, assuming no waterproof capacity at the joints. A theoretical model for calculating the hydraulic and earth pressures under bidirectional leakage conditions is developed, combining the method of images and Terzaghi’s formula to obtain the soil stress within the relaxed zone. In parallel, a cohesive zone model (CZM)-based approach is introduced to assess the long-term impacts of infiltration and exfiltration.Finally, building upon the previous work in this thesis, a computational framework is established to evaluate the long-term leakage impacts on the mechanical responses of the segmental tunnel-ground system in both 2D and 3D scenarios. By incorporating the hydro-mechanical coupled behaviour of gasketed joints, the framework illustrates the progressive leakage behaviour over time as influenced by joint deformations, gasket configurations, and internal water conditions, while comprehensively addressing the resulting consequences of soil-structure interactions and structural responses.
  

DOCTORAL DEGREE IN ELECTRICAL ENGINEERING

• BUSTO ABADIA, JAIME: Estudio y mejora del flujo armónico de cargas
  
  Author: BUSTO ABADIA, JAIME
  Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
  Programme: DOCTORAL DEGREE IN ELECTRICAL ENGINEERING
  Department: Department of Electrical Engineering (DEE)
  Mode: Normal
  Deposit date: 18/11/2025
  Reading date: 20/01/2026
  Reading time: 13:00
  Reading place: ETSEIB, aula H4.2
  Thesis director: MESAS GARCIA, JUAN JOSE | SAINZ SAPERA, LUIS
  Thesis abstract: The presence of voltage and current harmonics in electrical installations is a long-standing challenge in the field of power quality, a challenge that remains relevant today due to the continuous increase in nonlinear loads connected to these installations, the growing sensitivity of electrical devices to disturbances, and the need to predict and prevent problems arising from all the above factors. To address this, both standards that evaluate and quantify the tolerable limits of harmonic distortion for the electrical system and the loads connected to it have been developed, as well as various tools based on the formulation and numerical solution of the system of equations posed in harmonic load flow analysis. In addition, procedures to mitigate the harmonic problem have been studied. In this context, the development of the harmonic load flow formulation has always aimed to study the problem using the smallest possible number of equations that still yield correct results, thereby reducing the numerical problems involved in its mathematical solution without sacrificing accuracy. Although this formulation has already been extensively studied, researchers continue to propose improvements to it that allow the aforementioned objectives to be better achieved.Considering all the above, the objectives established in the thesis, which have ultimately been achieved, are:1.- Development and programming of a new harmonic load flow formulation that improves the convergence properties of current formulations.2.- Harmonic sensitivity analysis of the four most common types of nonlinear loads in electrical installations (single-phase and three-phase rectifiers with capacitive filters, three-phase 6-pulse rectifiers, and discharge lamps), and incorporation of the results into the new formulation.3.- Validation of the new formulation against those existing in the literature using a 3-bus academic network and an IEEE 14-bus network expanded to 23 buses.4.- Study of the harmonic cancellation phenomenon using the new formulation and the IEEE 14-bus network expanded to 23 buses.The following methodology was employed to achieve these goals:In the first part of the thesis, the state of the art of existing harmonic load flow formulations found in the literature was analysed, along with the treatment of variables, equations, and the problems they present. Then, the four common types of nonlinear loads in electrical installations were described, along with their modelling and their voltage and current responses to harmonic excitations.Subsequently, the new formulation was presented, including the theoretical foundations it is based on, the calculation stages it is divided into, as well as the data used and the unknowns to be calculated. The harmonic sensitivity analysis of nonlinear loads was also shown, which determines the differentiated treatment each will receive in the new formulation.Next, two application examples were presented to validate the results obtained. The new formulation was applied to two networks of different complexity, analysing the results and comparing them with those obtained using other existing formulations, both with single and aggregated loads.The final part addressed the study of harmonic cancellation in several groups of aggregated nonlinear loads, calculating the harmonic cancellation rate in each case using the new formulation developed.
  

DOCTORAL DEGREE IN GEOTECHNICAL ENGINEERING

• DAWI, MALIK ALI A: Process-Based Numerical Models to Assess Hydrogeochemical Effects of Microbial Biofilms in Porous Media
  
  Author: DAWI, MALIK ALI A
  Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
  Programme: DOCTORAL DEGREE IN GEOTECHNICAL ENGINEERING
  Department: Department of Civil and Environmental Engineering (DECA)
  Mode: Normal
  Deposit date: 16/10/2025
  Reading date: 19/12/2025
  Reading time: 10:00
  Reading place: ETSECCPB. UPC, Campus Nord Building C1. Classroom: 002C/Jordi Girona, 1-308034 Barcelona
  Thesis director: SANCHEZ VILA, FRANCISCO JAVIER | STARNONI, MICHELE
  Thesis abstract: Microorganism presence and spatial distribution over time in natural porous media, such as soils, sediments, and aquifers, play critical roles in mediating geochemical processes, influencing contaminant fate, and maintaining ecosystem functionality. In particular, microbial communities in the form of biofilms mediate complex biotransformation reactions, significantly altering the hydraulic properties of the host porous system. These dynamics, coupled with multiscale physical and chemical interactions, present major challenges for the predictive modeling of microbial processes in porous media. This thesis aims at developing a suite of computational models that integrate microbial growth and activity within flow and transport frameworks. The work is structured around three main contributions. First, a hybrid pore-scale model is developed which couples a micro-continuum representation of biofilms with a particle-based transport solver, enabling detailed analysis of how biofilm morphology and structure influence conservative solute transport. Second, this framework is extended to simulate the dynamic biofilm development and its interaction with groundwater flow, introducing a cohesive microporous model for biofilms that incorporates growth, attachment, spreading, and flow-induced detachment. A novel dimensionless number is introduced to characterize the interplay between hydrodynamic forces and biofilm cohesion. Third, we revisit Monod kinetics by proposing a mechanistic two-step reaction scheme that linearizes the growth rate expression, facilitating its integration into particle-based reactive transport models. This formulation is validated against batch experiments and applied to simulate microbial degradation in porous media. Finally, the thesis synthesizes these findings and outlines future directions for model development and experimental integration. By combining theoretical insights with computational advances, this work contributes to a deeper understanding of microbially mediated processes in porous media and provides modeling tools to support both hypothesis testing and experimental research in environmental and engineered systems.
  
• SAYAD NOGHRETAB, BABAK: HYDRO-MECHANICAL MODELING OF GAS FLOW THROUGH CLAY-BASED ENGINEERED ISOLATION BARRIERS
  
  Author: SAYAD NOGHRETAB, BABAK
  Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
  Programme: DOCTORAL DEGREE IN GEOTECHNICAL ENGINEERING
  Department: Department of Civil and Environmental Engineering (DECA)
  Mode: Normal
  Deposit date: 16/10/2025
  Reading date: 15/01/2026
  Reading time: 10:00
  Reading place: ETSECCPB.UPC, Campus NordBuilding C1. Classroom: 002C/Jordi Girona, 1-308034 Barcelona
  Thesis director: PUIG DAMIANS, IVAN | OLIVELLA PASTALLE, SEBASTIAN
  Thesis abstract: Safe management of high-level radioactive waste (HLRW) requires durable isolation from the biosphere over geologic time. Deep geological repositories (DGRs) rely on engineered and natural barriers, with bentonite as a key buffer and backfill material because it seals fractures, sorbs radionuclides, and develops swelling pressure during hydration. During operation and early post closure, resaturation and corrosion generate gas, so predicting system behavior requires coupled hydro gas mechanical models that represent double porosity, heterogeneity, and preferential pathways. This Thesis addresses that need by integrating explicit pathway mechanics in compacted buffers, double porosity constitutive laws for pellet/powder mixtures, and image-based statistics linked to finite element simulations in CODE_BRIGHT.First, a three-dimensional coupled hydro gas mechanical model of the large-scale gas injection test (LASGIT) is formulated with heterogeneous initial permeability, embedded fractures with dilatancy, and explicit gap closure states at the canister–buffer interface and is exercised through targeted sensitivity analyses. Second, the BENTOGAZ laboratory mixture of equal parts pellets and MX-80 powder is modeled with the Barcelona Expansive Model to couple microstructure and macrostructure; systematic parameter studies are complemented by a handmade heterogeneity setup that assigns distinct properties to randomly distributed pellet and powder domains. Third, an image to model workflow for SEALEX links micro-CT analysis to simulation: binarized slices yield macroporosity maps, directional variograms quantify anisotropy and correlation lengths, and the fitted statistics generate anisotropic porosity fields that enable automatic heterogeneity on the finite element mesh.Together, these methodologies constitute a set of methods that couple explicit fractures with dilatancy, dual structure behavior, and image informed spatial heterogeneity for repository relevant assessment of gas entry, resaturation, and sealing performance.
  

DOCTORAL DEGREE IN MECHANICAL, FLUIDS AND AEROSPACE ENGINEERING

• LU, YONGGANG: Research on Transient Flow Characteristics and Dynamic Behaviour of hydraulic Pumps in Support of Energy transition
  
  Author: LU, YONGGANG
  Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
  Programme: DOCTORAL DEGREE IN MECHANICAL, FLUIDS AND AEROSPACE ENGINEERING
  Department: Department of Mechanical Engineering (EM)
  Mode: Article-based thesis
  Deposit date: 26/11/2025
  Reading date: 16/01/2026
  Reading time: 11:00
  Reading place: Aula Laboratori Hidràulica, Pavelló D, planta -1, ETSEIB
  Thesis director: PRESAS BATLLÓ, ALEXANDRE
  Thesis abstract: Amid the global shift to low-carbon energy, multi-energy complementary power systems are key to achieving carbon neutrality. Nuclear energy, pumped storage hydropower, and industrial waste energy recovery enhance energy system flexibility but increase demands on energy transfer and fluid transport. Hydraulic pumps, vital for energy conversion, face challenges: RCPs in Generation IV lead-cooled reactors suffer from corrosion and vibration; pumped storage units face stability issues; and industrial waste pressure recovery is inefficient under variable conditions. This study focuses on three core devices—RCPs, pump-turbines, and PATs—using analysis, simulation, and experiments to investigate their dynamics and propose optimizations.First, the transient fluid-structure interaction of lead-bismuth eutectic RCPs during startup was studied. A mathematical model for flow rate and rotational speed under various startup modes was developed. Bidirectional fluid-structure interaction analysis showed maximum stress at the impeller blade root and maximum deformation at the blade-hub/shroud junction. Higher startup torque increased acceleration and torsional shock, with peak stress linked to instantaneous rotational speed. These findings inform safer RCP startup design.Second, the dynamic characteristics of reversible pump-turbines under load rejection were studied using 3D transient simulations and entropy production theory to analyze energy loss. The study found the unit crosses the S-shaped region during load rejection, with complex flow under reverse pump conditions. When speed exceeded 110%, significant fluctuations in axial hydraulic thrust and torque were observed, and blade pressure loads became asymmetric. These findings improve understanding of pump-turbine transient behavior.Finally, a two-stage PAT system for high-pressure energy recovery in petrochemicals was studied, focusing on vortex evolution and pressure pulsations. Pulsations in the diffuser stemmed from rotor-stator interaction near the tongue, with strong inter-stage interference at the inlet impeller. Low-frequency pulsations from vortex shedding were detected at high flow rates, threatening system stability. Combined experiments and simulations clarified pulsation propagation, aiding inter-stage matching and efficiency improvements.The innovative results of this study have been published in leading fluid mechanics and energy journals. They advance the theoretical understanding of hydraulic pump dynamics and provide practical solutions for nuclear safety, grid flexibility, and industrial energy conservation. The main body of the dissertation details each research component, with three supporting JCR Q1 articles appended.
  

DOCTORAL DEGREE IN NUCLEAR AND IONISING RADIATION ENGINEERING

• AL AWAD, ABDULRAHMAN: Multiscale Multiphysics Investigation of Helium Bubble Formation and Dynamics in Liquid Lead-Lithium Eutectic
  
  Author: AL AWAD, ABDULRAHMAN
  Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
  Programme: DOCTORAL DEGREE IN NUCLEAR AND IONISING RADIATION ENGINEERING
  Department: Department of Physics (FIS)
  Mode: Normal
  Deposit date: 03/11/2025
  Reading date: 16/12/2025
  Reading time: 11:00
  Reading place: Aula C4 (porta 31.07) Secció d'Enginyeria Nuclear, pavelló C, ETSEIB (Campus Sud)
  Thesis director: BATET MIRACLE, LLUIS | SEDANO MIGUEL, LUIS ANGEL
  Thesis abstract: Liquid metals (LMs) and their alloys are characterized with excellent thermophysical and dynamic properties for heat transport purposes, thus rendering them as promising candidates in advanced energy-production technologies such as the nuclear fusion energy. Liquid lead-lithium eutectic (LLE) alloy remains a key medium of the various breeding blanket (BB) concepts of the EU DEMO design. In LLE-BBs, helium (He) is produced in a mole-to-mole ratio with tritium by nuclear reactions, and technical concerns regarding the state of He in liquid LLE alloy have been raised since the 1990s. Gas-bubble nucleation in weak liquid–gas solutions has been a challenging topic in theory, experimentation, and computer simulations, especially given the expected very low solubility of He in LMs and the scarcity of experimental data. Despite the continuous efforts, the He nucleation issue still lacks conclusive findings and robust estimations of relevant parameters, and the main objective of this thesis is to exploit ab initio (AIMD) and classical molecular dynamics (CMD) simulations in order to shed light on the underlying physics and theory, and to estimate the thermodynamic and kinetic conditions required for He bubbles to nucleate and grow in a manner that facilitates the integration of results and findings into macroscopic models, e.g., CFD models, for engineering design and nuclear safety purposes. Additionally, it aims to pave the way and generally contextualize the use of atomistic simulations in the field. In the first part of this thesis, the invaluable AIMD methods using SIESTA code are utilized to support and justify the selection and construction of classical interatomic potentials, where liquid Li, Pb and LLE alloy are systematically investigated. In the second part, a classical potential of the embedded-atom-method class is parametrized for liquid Li using mechanical and non-mechanical properties. A mixing scheme is introduced to reproduce properties of liquid LLE alloy. To minimize the arbitrariness of functional forms, the parametrization schemes address the uniqueness problem. CMD simulations with LAMMPS code are performed to extensively investigate and estimate static and dynamic properties of pure LM and He/LM systems, both bulk and interfacial properties. In the third part, in analogy with recent advances in crystallization and droplet formation studies, the diffusive-shielding stabilization, the thermodynamic irreversibility of bulk nanobubbles (bNBs) mechanisms and the mean-first passage times theory are revisited and deployed to characterize the stability of He-bNBs in liquid LLE alloy, as inspired from bubble stability theories and experiments in closed and finite-volume systems. Namely, an analytical perturbation approach with an appropriate equation-of-state of He-bNBs and a stochastic and kinetic approach via forward CMD simulations are established, and the consistency and equivalency of both is demonstrated and thoroughly discussed. Most importantly, the underlying theoretical bases, assumptions, limitations and their computational counterparts are extensively described and illustrated. The overall proposed framework resolves ambiguities about the influence of the simulation domain and time on the observed bNBs in CMD simulations. Essentially, it provides a novel and plausible explanation for helium-bNBs existence and persistence by carefully assessing and estimating the thermodynamic equilibrium conditions; hence, their stability and longevity are shown not to be in violation of the fundamental laws of solubility and diffusivity, at least in CMD simulations and given the relatively high supersaturation levels. Lastly, thermodynamic and kinetic conditions required for the helium nucleation phenomena to take place at LLE-BBs operating conditions are inferred, based on the various investigated theories and performed computations, and coherently, macroscopic modelling suggestions and recommendations are provided.
  

DOCTORAL DEGREE IN PHOTONICS

• CHIEN, YING-HAO: Revealing Ultrafast Dynamics in Hexagonal Boron Nitride with Attosecond X-ray Absorption Fine-structure Spectroscopy
  
  Author: CHIEN, YING-HAO
  Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
  Programme: DOCTORAL DEGREE IN PHOTONICS
  Department: Institute of Photonic Sciences (ICFO)
  Mode: Normal
  Deposit date: 16/10/2025
  Reading date: 27/01/2026
  Reading time: 10:00
  Reading place: ICFO Auditorium
  Thesis director: BIEGERT, JENS
  Thesis abstract: Since the invention of the integrated circuit (IC) in the 1950s, modern civilization has been built upon its foundation. As ICs continue to scale down and operate at higher speeds, managing heat dissipation and energy transfer process is critical to overcoming performance limitations and enabling the development of next-generation ICs. In classical models, electrons and phonons are treated as independent systems to simplify calculations. This approximation successfully describes electronic band structures, charge transport, and optical responses in many materials under equilibrium conditions. However, it neglects the critical role of electron-phonon coupling, a fundamental many-body interaction that governs non-equilibrium energy exchange between electronic and lattice degrees of freedom. Recent advances in attosecond X-ray absorption fine structure (atto-XAFS) spectroscopy offer an unprecedented opportunity to observe electron-phonon coupling dynamics with both attosecond temporal and element-specific resolution. Hexagonal boron nitride (hBN), a widely studied prototypical material with diverse applications, still presents unresolved questions regarding its ultrafast dynamics. In this work, we investigate the coupled electron and phonon dynamics in bulk hBN using atto-XAFS. By employing different excitation conditions and exploiting different temporal resolutions, we disentangle the respective contributions of electrons and phonons to the transient response, demonstrating the unique capability of atto-XAFS to probe many-body dynamics in real-time. To enable further studies of novel materials, we upgraded our titanium-doped sapphire (Ti:sapphire) chirped pulse amplification (CPA) laser system, integrated a new commercial TOPAS optical parametric amplifier, designed a novel microfluidics gas target combined with a piezo pulse valve system aimed at reducing helium consumption for high harmonic generation (HHG), implemented a cryogenic sample mount for temperature-dependent measurements, and replaced the diffraction grating in the soft X-ray spectrograph with high diffraction efficiency and high resolving power reflection zone plates. We demonstrate the enhanced performance of the upgraded system for future advanced atto-XAFS experiments.
  
• KOKABEE, OMID: High-power ultrafast optical parametric oscillators from the visible to mid-infrared
  
  Author: KOKABEE, OMID
  Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
  Programme: DOCTORAL DEGREE IN PHOTONICS
  Department: Institute of Photonic Sciences (ICFO)
  Mode: Normal
  Deposit date: 09/07/2025
  Reading date: 17/12/2025
  Reading time: 10:00
  Reading place: Elements Room
  Thesis director: EBRAHIM-ZADEH, MAJID
  Thesis abstract: The introduction of electric lighting in Architecture marked a profound transformation in its design conception, establishing artificial light as a fundamental element in the configuration of space. Unlike other artistic and architectural disciplines, artificial architectural lighting lacks a formalised Art History. Existing specialist literature remains largely focused on technical and quantitative aspects, frequently relegating the qualitative dimensions of light in space to a secondary status. Consequently, there is a notable absence of a specific vocabulary capable of accurately describing the qualitative effects of lighting in architecture. This lexical gap hampers the effective communication of lighting-related spatial concepts, ultimately to the detriment of architectural practice. In light of these challenges, and with the aim of improving both design and pedagogical methodologies, this research advocates for the establishment of a dedicated vocabulary for qualitative architectural lighting. It is predicated on the hypothesis that it is feasible to construct a consensual glossary that enables the precise articulation of the formal and spatial attributes of lighting effects within architectural environments. To substantiate this hypothesis, the research sets out two principal objectives: first, to identify the parameters that define the qualitative aspects of lighting and to compile the associated terminological corpus; second, to develop a lexical and visual dictionary in which each term is clearly defined and illustrated, thereby facilitating its comprehension and application in both academic and professional contexts, and contributing to the standardisation of a specific and practical language.The study adopts a qualitative methodological framework, centred on the linguistic analysis of texts describing architectural lighting projects, which have been published in specialised Spanish-language media. A rigorous, systematic, and replicable terminology methodology has been employed, drawing upon established principles from the field of Terminology studies and related research on lighting perception. The process integrates automated term extraction methods, enabling efficient handling of large data sets, and applies linguistic techniques adapted to the visual domain. The research identifies the principal parameters defining the formal qualities of architectural lighting as direction, colour, and distribution, followed by quantity, luminance, sources, informational content, perceptual effects, and others. Among these, the distribution parameter emerges as the most frequently cited and, thus, the most critical for both configuring and describing architectural lighting. Accordingly, the dictionary focuses on the most recurrent terms related to distribution, listed alphabetically as follows: accent lighting, ambient lighting, composed lighting, diffuse lighting, direct lighting, directed lighting, dispersed lighting, focalized lighting, general lighting, grazing lighting, homogeneous lighting, horizontal lighting, indirect lighting, integrated lighting, precise lighting, projected lighting, reflected lighting, uniform lighting, and vertical lighting. It has been demonstrated that each of these terms can be defined in a manner that supports clear, precise, and intelligible communication within architectural lighting discourse. Furthermore, it is feasible to identify corresponding visual representations that exemplify each definition, reinforcing their pedagogical and practical applicability. In conclusion, this research affirms the viability of developing a consensual glossary of terms to imporve the communication of the formal and spatial characteristics of lighting effects within architectural practice, which constitutes a foundational step toward the recognition and standardisation of qualitative lighting vocabulary in the discipline.
  

DOCTORAL DEGREE IN POLYMERS AND BIOPOLYMERS

• HASSANKALHORI, MAHDI: From Ion Channels to Industrial Enzymes: Modeling and Modulating Protein Functional Properties
  
  Author: HASSANKALHORI, MAHDI
  Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
  Programme: DOCTORAL DEGREE IN POLYMERS AND BIOPOLYMERS
  Department: Department of Chemical Engineering (EQ)
  Mode: Normal
  Deposit date: 19/11/2025
  Reading date: 02/02/2026
  Reading time: 11:00
  Reading place: ESCOLA D'ENGINYERIA BARCELONA EST C/Eduard Maristany, 16 (08019 Barcelona) 934137400 Sala Polivalent Edifici A https://eebe.upc.edu/ca/lescola/com
  Thesis director: TORRAS COSTA, JUAN | LUCAS, MARIA FÁTIMA ASSUNÇAO
  Thesis abstract: Recent advances in computational molecular modeling have significantly enhanced our understanding of protein structure and function, enabling the design and optimization of biomolecules for diverse applications, for instance in biosensing and industrial biocatalysis. This thesis aimed to leverage integration of innovative computational methodologies to investigate and modulate the functional properties of four distinct protein targets from two protein families: ion channels, specifically human acid-sensing ion channels (hASIC1a and hASIC3), and enzymes, including an artificial enzyme based on the Lactococcal Multidrug Resistance Regulator (LmrR) protein scaffold and thermophilic Streptomyces sclerotialus Tyrosine Hydroxylase (SsTyrH). Depending on the case and objectives, we employed an integration of computational protein structure prediction, molecular dynamics simulations, protein residue network analysis, an specialized ion binding site prediction tool and a machine learning-based model for functional site prediction to identify key positions involved in protein function, regulation and other relevant properties. Our findings include the discovery of novel functional regulatory sites in hASIC1a and the design of mutations that confer sustained currents in hASIC1a, the prediction of the potential calcium binding sites in hASIC3 for guiding the experimental identification and functional characterization of such regulatory positions. Furthermore, integrative computational approaches successfully led to the prediction of functional distal hotspots and improved variants in the LmrR-based enzymatic system and SsTyrH, all validated by experimental characterization. This research demonstrates the efficacy of integrating computational methodologies to engineer proteins with tailored functional properties, providing valuable insights for the development of optimized ion channels for biotechnological applications and industrial biocatalysts, as well as advancing our understanding of protein structure-function relationships.
  
• MINGOT BEJAR, JULIA: Applications of Poly(N-isopropylacrylamide)-based Hydrogels in Chemical Engineering
  
  Author: MINGOT BEJAR, JULIA
  Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
  Programme: DOCTORAL DEGREE IN POLYMERS AND BIOPOLYMERS
  Department: Department of Chemical Engineering (EQ)
  Mode: Normal
  Deposit date: 21/11/2025
  Reading date: pending
  Reading time: pending
  Reading place: pending
  Thesis director: ARMELIN DIGGROC, ELAINE APARECIDA | LANZALACO, SONIA
  Thesis abstract: This doctoral thesis explores the multifunctionality of poly(N-isopropylacrylamide) (PNIPAAm)-based hydrogels as a platform for biomedical and environmental applications. By exploiting the thermoresponsive properties of PNIPAAm and its copolymers, the research demonstrates how this material can be engineered to perform in distinct technological domains.In the biomedical field, inert polypropylene surgical meshes, commonly used for hernia repair, were functionalised with gold nanoparticles and a Raman reporter, converting their surface into a SERS-active platform. Covalent grafting of PNIPAAm-based copolymers onto the plasmonic substrate imparted thermoresponsive behaviour, resulting in an implantable device capable of simultaneous SERS detection and thermal response. In vitro assays with fibroblast cells confirmed the biocompatibility and stability of the device, highlighting its potential for minimally invasive diagnostics and post-surgical monitoring.A complementary theranostic approach was applied to the modification of 3D polyurethane sponges, used in endoluminal vacuum-assisted therapies, with PNIPAAm hydrogel and metallic nanoparticles. Functionalisation with gold and silver nanoparticles, stabilised by biopolymer shells, endowed the modified sponges with antibacterial properties. Photothermal activation under Raman laser irradiation resulted in significant antimicrobial activity against Escherichia coli and Staphylococcus aureus, offering new prospects for infection detection and treatment in implantable devices.In the environmental section, the thermoresponsive behaviour of PNIPAAm hydrogels was exploited for solar-driven water desalination and sustainable energy generation. A PNIPAAm-alginate-PEDOT:PSS system exhibited enhanced water evaporation rates potentiated by the consecutive surface contraction of the hydrogel (“pudding effect”). Further developments involved PNIPAAm-gelatine hydrogels incorporating carbon black as photothermal absorber, achieving stable desalination performances under real conditions (outdoor sunlight), with demonstrated durability and reusability.Finally, PNIPAAm-based matrices were employed to fabricate hydrogel thermal electricity generators. This combination of PNIPAAm with doped conductive polymers enabled photothermal-to-electric energy conversion driven by ionic transport within the hydrogel network upon exposure to solar light.Overall, this thesis establishes PNIPAAm hydrogels as a highly adaptable material platform. Their thermoresponsive behaviour, combined with plasmonic or photothermal functionalities, offers potential solutions to challenges in healthcare and resources sustainability.
  

DOCTORAL DEGREE IN SIGNAL THEORY AND COMMUNICATIONS

• IRAWAN, AMIR MUSTOFA: Explainable Artificial Intelligence Applied to Geoscience and Remote Sensing: Development and Application to Wild Fire Forecasting Related to Climate Change
  
  Author: IRAWAN, AMIR MUSTOFA
  Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
  Programme: DOCTORAL DEGREE IN SIGNAL THEORY AND COMMUNICATIONS
  Department: Department of Signal Theory and Communications (TSC)
  Mode: Normal
  Deposit date: 17/11/2025
  Reading date: 20/01/2026
  Reading time: 11:30
  Reading place: Aula de Teleensenyament, Edifici B3, Campus Nord UPC, Barcelona
  Thesis director: VALL-LLOSSERA FERRAN, MERCEDES MAGDALENA | LOPEZ MARTINEZ, CARLOS
  Thesis abstract: this thesis presents a progressive exploration of wildfire prediction by integrating process-based understanding with machine learning and causal inference frameworks. Chapter 3 focuses on variable importance and sensitivity by applying perturbation-based interventions, altering key drivers such as vapour pressure deficit (VPD), soil moisture (SM), and jet stream metrics by up to ±25% to simulate intensified environmental conditions and assess their impact on burned area. In contrast, Chapter 4 employs formal causal inference through do-calculus, enabling targeted counterfactual analysis within a structural causal model (SCM). Unlike the continuous perturbation-based interventions in Chapter 3, the intervention scenarios here are implemented by bootstrapping input variables and setting them to the 25th, 50th, 75th, and 100th percentiles. This allows the model to simulate the impact of each variable across a range of conditions, from typical to extreme (worst-case), and to quantify both direct and indirect effects on burned area, particularly for key drivers such as ∆Z500 and v300. Chapter 5 extends the causal reasoning to a global scale by using PCMCI-derived graphs as structural priors within a deep learning framework. It introduces regime-specific directed acyclic graphs (DAGs) generated through spatial clustering using the DBSCAN algorithm, enabling the identification of region-specific land–atmosphere interactions. These causal graphs are then embedded into Graph Attention Networks (GATs), allowing the model to learn weighted connections informed by causal structure, thereby enhancing both predictive performance and physical interpretability. Finally, Chapter 6 synthesizes these advances by embedding causal graphs within a GAT to simulate complex, multiscale interventions. It incorporates explicit counterfactual scenarios simulating intensified El Niño (via doubled negative SOI) and jet stream ridging (via increased positive ∆Z500, v300, and jet core), revealing spatially distinct fire responses. The use of different intervention strategies across chapters reflects the evolving methodological focus, from assessing input sensitivity (Chapter 3), to inferring causal mechanisms (Chapter 4), validating causal structures across regions (Chapter 5), and finally quantifying scenario-based outcomes (Chapter 6). Building on this foundation, Chapter 6 introduces a causal GAT capable of predicting global burned area by integrating physically grounded causal graphs derived from PCMCI. This approach enables the model to follow meaningful land–atmosphere interactions, improving interpretability and aligning predictions with known physical processes. The results show that the causal GAT outperforms models using fully connected graphs. Excessive or non-informative edges in fully connected structures can lead to over-smoothing, a common issue in Graph Neural Networks, where repeated message passing across redundant links blurs key distinctions among node representations. This can obscure critical predictive features and degrade overall model accuracy. By pruning spurious or weakly informative connections, the causal GAT preserves sharper, more meaningful node embeddings and avoids the performance loss typically associated with over-parameterized graph structures. Collectively, these advances underscore that correlation-based models fail to capture the complex, non-linear interactions among ignition sources, vegetation dynamics, and climate feedbacks. They advocate for a shift toward process-based and machine learning models that can better represent the multifaceted mechanisms governing wildfire regimes in a warming world.
  
• TRULLENQUE ORTIZ, MARTÍN: A Cross-Layer Perspective on Radio Resource Management and User Quality of Experience in V2X-Enabled 5G Networks.
  
  Author: TRULLENQUE ORTIZ, MARTÍN
  Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
  Programme: DOCTORAL DEGREE IN SIGNAL THEORY AND COMMUNICATIONS
  Department: Department of Signal Theory and Communications (TSC)
  Mode: Normal
  Deposit date: 31/10/2025
  Reading date: 15/12/2025
  Reading time: 11:00
  Reading place: Aula de Teleensenyament. Edifici B3, Campus Nord
  Thesis director: SALLENT ROIG, JOSE ORIOL | CAMPS MUR, DANIEL
  Thesis abstract: Vehicular communications are expected to be among the main verticals benefiting from the massive rollout of 5G. The millisecond latencies enabled by 5G, combined with network slicing and the global coverage offered by public cellular networks, leverage the conditions to adopt public cellular networks for vehicle-to-everything (V2X) communications. This vertical will introduce new services that generate additional traffic demands on existing radio infrastructure, posing distinct challenges for mobile network operators. From a service perspective, V2X services require both low latency and high reliability. For example, under a periodic exchange position information between vehicles, a single dropped packet can increase the position error estimate and jeopardize road safety. From a network perspective, vehicular services will demand resources differently from generic Internet users, often creating high user densities along highways, where user density is typically [MT1.1]low and radio deployment is not dense. Moreover, vehicle mobility can lead to long periods during which cells serve very few users, followed by periods of high demand that may compromise resource availability, especially during traffic congestion. To this end, this thesis investigates solutions for cell overloads caused by traffic jams when V2X services run over public cellular networks.The first contribution of this work is an in-depth analysis of vehicular mobility based on a dataset of realistic traces, aimed at understanding how traffic congestion drains radio resources. Studying vehicle flows across cells reveals user concentrations at specific road locations, providing opportunities for congestion control mechanisms. The second contribution examines the repeatability of high-load situations in a real 5G deployment. Measurements over a 5G NSA network show that congestion exhibits consistent daily patterns, duration, and load characteristics, motivating deterministic congestion control strategies.Building on these insights, this thesis proposes and implements two complementary approaches: a network-layer mobility load balancing algorithm that diverts vehicles at cell edges to neighbouring cells during traffic jams, and an application-layer mechanism that manages service degradation to control packet loss under overload. Combining both approaches, this thesis has conceived, designed, implemented and evaluated FOM-5G, a framework capable to derive the best congestion control strategy for each cell overload. The framework leverages the use of historical information data to optimize cell congestion responses through experience. Beyond its design and evaluation, the thesis also proposes an architectural integration of FOM-5G within the O-RAN architecture and network exposure API defined in the 5G core. Finally, the framework is validated through simulations using diverse vehicular traces that capture urban congestion scenarios. Results confirm FOM-5G’s ability to distinguish between different congestion events and select the optimal mitigation strategy, demonstrating its effectiveness in ensuring reliable V2X communications over public cellular networks.
  
• YI, TIEYAN: UAV SAR Interferometry: ARBRES-X Data
  
  Author: YI, TIEYAN
  Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
  Programme: DOCTORAL DEGREE IN SIGNAL THEORY AND COMMUNICATIONS
  Department: Department of Signal Theory and Communications (TSC)
  Mode: Normal
  Deposit date: 04/11/2025
  Reading date: 20/01/2026
  Reading time: 11:00
  Reading place: Aula MERIT D5-010, Campus Nord UPC, Barcelona
  Thesis director: MALLORQUI FRANQUET, JORDI JOAN
  Thesis abstract: Small UAVs are attractive SAR platforms, but their unstable trajectories and imperfect GPS/IMU logs introduce significant motion errors that degrade image quality. The ARBRES-X system employs wide-beam, high-squint acquisitions that favor short-aperture observations, while simultaneously reducing sensitivity to motion errors. This thesis first reviews the fundamentals of SAR imaging and cross-track interferometry, then analyzes the ARBRES-X system characteristics in detail, with particular attention to how short apertures and wide beams affect processing. The accuracy requirements for platform state in SAR imaging and cross-track interferometry are quantified, revealing that off-the-shelf INS solutions are insufficient. To address this gap, a motion-error estimation algorithm is proposed and validated using simulated data. Building on these results, an end-to-end processing framework for SAR imaging and cross-track interferometry is developed and applied to ARBRES-X data. The framework produces highly coherent interferograms, and differential interferograms clearly detect PARC phase changes induced by controlled deformation, in close agreement with theoretical predictions. In addition, a speed optimization method suitable for short-aperture imaging is also demonstrated.
  

DOCTORAL DEGREE IN STATISTICS AND OPERATIONS RESEARCH

• GROTTO, ANDREA: Optimal transition towards zero tailpipe emission mobility in urban and suburban areas
  
  Author: GROTTO, ANDREA
  Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
  Programme: DOCTORAL DEGREE IN STATISTICS AND OPERATIONS RESEARCH
  Department: Department of Statistics and Operations Research (EIO)
  Mode: Normal
  Deposit date: 01/10/2025
  Reading date: 18/12/2025
  Reading time: 11:00
  Reading place: FIB Sala d'actes Manuel Martí Recober B6-planta 0
  Thesis director: FONSECA CASAS, PAU | ZUBARYEVA, ALYONA
  Thesis abstract: This doctoral research presents an innovative methodological framework for developing Urban Mobility Digital Twins through formalization using the Specification and Description Language (SDL). The study addresses the challenges of urban mobility management in the context of digital transformation and Society 5.0 principles, where technology serves human needs rather than the opposite.The research combines SUMO with its integrated SAGA module, formalized through SDL to enable conceptual model validation by stakeholders. This methodology enables continuous validation of digital twin models through real-time data integration from Internet of Things sensors and traffic monitoring systems distributed throughout urban networks.The conceptual model is demonstrated through a proof-of-concept implementation in Bolzano City. In this implementation, the BSc block integrates activity-based modelling with microscopic traffic simulation, with multi-objective optimization across energy consumption, CO2 emissions, and urban traffic congestion criteria. As an example, the implementation focuses on electric vehicle adoption optimization scenarios.The research is conducted in collaboration with Urban Resilience, a company developing SUMOSU sustainable mobility hubs that integrate electric charging infrastructure, shared vehicles, and photovoltaic renewable energy systems. This collaboration demonstrates the framework's practical applicability in evaluating integrated and sustainable mobility solutions.Additionally, comprehensive validation protocols are developed and formalized through SDL, including specific procedures for data validation, operational validation, experimental validation based on Design of Experiments methodology, and solution validation. These protocols ensure systematic and reproducible validation processes across different environmental and seasonal conditions.Main contributions include: development of a conceptual model for Urban Mobility Digital Twins facilitating stakeholder communication regardless of technical background; establishment of continuous validation protocols distinguishing true Digital Twins from static simulation models; integration of mobility and energy systems within a unified framework supporting sustainability evaluations; alignment with Society 5.0 principles by transforming complex technical systems into accessible decision-making tools.The research establishes methodological foundations for connecting Urban Mobility Digital Twins with other urban digital twins or models through common formalization approaches. This enables analysis of complex urban interactions while maintaining human-centered technological development through the conceptual model that expresses what is contained within the Digital Master of the Digital Twin.Results demonstrate that the formalization successfully creates a common language for urban mobility stakeholders, enabling effective collaboration between diverse professional domains and facilitating the adoption of sustainable technologies in urban contexts.
  

DOCTORAL DEGREE IN SUSTAINABILITY

• ADAMO, ANGELA: Contribution to the decarbonisation of energy intensive industries in the path of the European Union objectives. Application to the case study of SEAT
  
  Author: ADAMO, ANGELA
  Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
  Programme: DOCTORAL DEGREE IN SUSTAINABILITY
  Department: University Research Institute for Sustainability Science and Technology (IS.UPC)
  Mode: Article-based thesis
  Deposit date: 18/11/2025
  Reading date: 12/01/2026
  Reading time: 16:00
  Reading place: Sala polivalent, EEBE, Edifici A, Campus Diagonal-Besós
  Thesis director: MARTIN CAÑADAS, MARIA ELENA | DE LA HOZ CASAS, JORGE
  Thesis abstract: The urgent need to address climate change is intensifying global efforts to decarbonize all sectors, especially the industrial sector, which remains one of the most challenging due to its high-temperature demands and complex operations. Among the most promising solutions is electrification through High Temperature Heat Pumps (HTHPs), potentially combined with electric boilers.This thesis assesses the decarbonization potential of HTHPs in industrial cogeneration systems, using a real case study: the Combined Heat and Power (CHP) plant at SEAT’s automotive factory in Martorell, Spain. Currently powered by natural gas, the plant provides superheated water (SHW) and is a major source of the site’s CO₂ emissions, while facing increasing environmental and regulatory pressure.Unlike prior studies that use simplified or idealized models, this work develops a high-fidelity hybrid thermodynamic model of the CHP system, based on one year of operational data and realistic constraints of electrification technologies. Two modeling approaches were explored—a purely thermodynamic model and a hybrid model integrating empirical data to compensate for sensor inaccuracies. The hybrid model, with lower error margins, was chosen for further analysis.The model includes all major components: gas and steam turbines, post-combustion heat recovery boiler (HRB), absorption chillers, air coolers, and auxiliary boilers, enabling accurate simulation of the plant under real conditions. The technical and economic viability of replacing gas-based heat production with HTHPs and electric boilers was assessed, considering performance limitations (e.g., efficiency loss at high temperatures), availability of low-temperature heat sources, and electricity market dynamics.A key contribution is the evaluation of how current regulatory and market conditions—especially incentives favoring gas-based CHP—impact the competitiveness of electrified solutions. The thesis concludes by analyzing optimal HTHP sizing under various scenarios, considering CO₂ pricing, thermal demand, and plant dynamics.Findings suggest that, although technically feasible, electrification is significantly influenced by regulatory and economic frameworks. The study highlights the importance of detailed modeling, realistic assumptions, and strategic alignment. It also reveals a broader issue: many industrial players lack the data infrastructure and planning needed to implement deep decarbonization. This work provides a replicable methodology and valuable insights for engineers, operators, and policymakers committed to reducing industrial carbon emissions.
  

DOCTORAL DEGREE IN URBANISM

• MARTÍ ELÍAS, JOAN MARIA: Hidrografies urbanes. Cicle de l’aigua, forma urbana i estructura territorial al la Vall Baixa i al Delta del Llobregat
  
  Author: MARTÍ ELÍAS, JOAN MARIA
  Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
  Programme: DOCTORAL DEGREE IN URBANISM
  Department: Department of Urbanism, Territory and Landscape (DUTP)
  Mode: Normal
  Deposit date: 31/10/2025
  Reading date: 15/12/2025
  Reading time: 17:00
  Reading place: ETSAB (Escuela Técnica Superior de Arquitectura de Barcelona) - Planta Baja - Sala de GradosAv. Diagonal, 649-651 - 08028 - Barcelona
  Thesis director: CROSAS ARMENGOL, CARLES
  Thesis abstract: The research dives in the relationship between urban morphology and water cycle from an ecosystemic perspective that integrates physical, territorial, and infrastructural components. The objective is to demonstrate that urban morphology is directly related with hydrological dynamics and that, therefore, it can become a key tool for redefining water management strategies in metropolitan contexts.This dissertation is grounded in the intensive exploration of a specific territory (la Vall Baixa and the Delta del Llobregat) through five successive approaches, addressing the territory from the metropolitan scale down to local urban fabrics. This process constructs a multi-scalar reading that relates the physical, infrastructural, and morphological conditions of the city to its hydrological dynamics.The territorial approach is enriched by a historical and conceptual dimension that reconstructs a genealogy of urban thought in an ecosystem perspective, based on figures and projects that conceived the city as a living system, dependent on its exchanges with the territory. The research also revisits nineteenth-century projects that, with a hygienist outlook, anticipated “proto-ecological” visions. In this regard, Garcia Fària’s proposal for the sanitation of the Eixample and the diversion of the river Llobregat constitutes a paradigmatic case that anticipates an integrated territorial interpretation, establishing a valuable precedent for contemporary urban planning practice.On this basis, the final stretch of the river Llobregat is studied, revealing the complexity of a hybrid morphology resulting from the superimposition of natural and anthropic logics. The river is presented as an ecological and productive infrastructure, a space where the persistence of hydraulic and agricultural traces coexists with metropolitan urbanization pressures. From here, the research turns to the underground dimension, analyzing the delta aquifer as a key element for environmental balance. Infiltration dynamics, alterations derived from urbanization, and opportunities for the reconversion of industrial and logistical spaces based on hydrogeological criteria are examined. The three-dimensional reading of the territory makes it possible to link surface and subsoil and to propose infiltration and regulation devices that restore natural functions.In the central part of the dissertation, these criteria are applied at an intermediate analytical scale, proposing the sub-basin as a functional unit of analysis and design, due to its capacity to integrate topographical continuities, road structures, and open spaces. On this basis, a parametric methodology is developed, articulated into six actions (capture, consumption, treatment, infiltration, retention, and reuse) applied to multiple metropolitan fabrics. A multi-scalar analysis makes it possible to identify hydromorphological indicators that guide design decisions according to context and urban structure. The result is an operative atlas that proposes ranges of intervention and adaptive criteria for urban transformation guided by hydrological principles.Finally, the research advances a paradigm shift: water becomes a design vector, not merely a technical constraint. Public space, the road network, and urban voids are recognized as multifunctional water devices, while the underground dimension is considered an active and inseparable layer of the urban system. This three-dimensional and complex vision relates metabolism and form, while articulating both regional scale and urban project.Overall, the dissertation contributes to creating a culture of urban design that integrates water as a vector of intelligibility and ordering, where the term “hidrografia” is not understood in the traditional sense of describing river courses, but rather as a critical instrument for mapping the presence, movement, and structuring capacity of water in all its forms.
  

DOCTORAL DEGREE IN ARTIFICIAL INTELLIGENCE

• ZHAO, RUI: Improving SAT and Pseudo-Boolean Solving Technology
  
  Author: ZHAO, RUI
  Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
  Programme: DOCTORAL DEGREE IN ARTIFICIAL INTELLIGENCE
  Department: Department of Computer Science (CS)
  Mode: Normal
  Deposit date: 15/12/2025
  Deposit END date: 08/01/2026
  Thesis director: OLIVERAS LLUNELL, ALBERT
  Thesis abstract: The Boolean satisfiability (SAT) problem has seen remarkable progress, from early DPLL and resolution methods to the modern Conflict-Driven Clause Learning (CDCL) paradigm. Nevertheless, significant challenges remain. Theoretically "simple" yet structurally complex problems, such as the pigeonhole principle, continue to challenge state-of-the-art SAT solvers, revealing inherent limitations in core algorithms like CDCL. Although CDCL-based Pseudo-Boolean (PB) solving extends SAT with 0-1 linear arithmetic constraints—enabling more natural modeling and offering exponential speedups in theory—its added complexity introduces computational bottlenecks in propagation, conflict analysis, and optimization. These challenges underscore the need for deeper algorithmic insights and innovative techniques to advance SAT and PB solver performance. This thesis addresses these gaps by advancing the core algorithms and implementation techniques underlying modern SAT and PB solvers. It is structured in two parts:• Part I: SAT Solving – We analyze the limitations of CDCL through both theoretical and practical lenses. The contributions are: (i) new insights from analyzing multiple conflicts, aimed at identifying opportunities to enhance CDCL or understanding the fundamental reasons for the failure of this particular idea; (ii) an empirical study on the equivalence between CDCL solvers and resolution, examining how solvers reproduce unsatisfiability proofs and how decision heuristics and resolution proofs interact.• Part II: Pseudo-Boolean Solving – We introduce optimizations in unit propagation and conflict analysis. Propagation is accelerated through a carefully engineered hybrid technique, while enhanced conflict analysis produces some stronger constraints for more effective search pruning.Beyond performance gains, this work offers profound insights into Boolean constraint reasoning, bridging theoretical gaps and opening new research avenues in SAT, PB, and beyond.
  

DOCTORAL DEGREE IN CIVIL ENGINEERING

• DEHGHANSOURAKI, DANIAL: Modeling Sediment Transport in Rivers and Reservoirs using an Accelerated Model
  
  Author: DEHGHANSOURAKI, DANIAL
  Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
  Programme: DOCTORAL DEGREE IN CIVIL ENGINEERING
  Department: Department of Civil and Environmental Engineering (DECA)
  Mode: Article-based thesis
  Deposit date: 04/12/2025
  Deposit END date: 18/12/2025
  Thesis director: BLADE CASTELLET, ERNEST | LARESE DE TETTO, ANTONIA
  Thesis abstract: Reservoir sedimentation is a critical, ongoing issue in managing water resources sustainably. While conventional two-dimensional models are computationally efficient, they miss key three-dimensional processes, such as thermal stratification. Three-dimensional models provide a more accurate physical representation but require extensive computational resources, making them impractical for large-scale applications. This research creates a computational framework that combines High-Performance Computing, Artificial Intelligence, and advanced 3D multiphysics simulation to bridge this gap.A two-dimensional hydro-morphodynamic model (R-Iber) was rebuilt for Graphics Processing Units, resulting in computational speed-ups of one to two orders of magnitude. The accelerated model supported training a Deep Neural Network surrogate, enabling a 100,000-run Monte Carlo analysis for robust model calibration and uncertainty quantification. In parallel, a comprehensive three-dimensional multiphysics model was developed in the Kratos framework to simulate the 3D fluid-thermal problem.The integrated approach was used for the Riba-roja reservoir system. It measured how thermal stratification affects sediment trapping efficiency. Results show that combining HPC, AI, and multiphysics modeling leads to practical and actionable methods for sustainable reservoir management.
  

DOCTORAL DEGREE IN COMPUTER ARCHITECTURE

• ALCÓN DOGANOC, MIGUEL: Verification and Validation Solutions for the Safety Compliance of Autonomous Driving Frameworks Performance Aspects
  
  Author: ALCÓN DOGANOC, MIGUEL
  Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
  Programme: DOCTORAL DEGREE IN COMPUTER ARCHITECTURE
  Department: Department of Computer Architecture (DAC)
  Mode: Normal
  Deposit date: 01/12/2025
  Deposit END date: 15/12/2025
  Thesis director: ABELLA FERRER, JAIME | MEZZETTI, ENRICO
  Thesis abstract: Autonomous Driving (AD) has rapidly evolved from a research concept into an industrial reality. The increasing computational demands of autonomous vehicles have motivated the use of high-performance Multi-Processor Systems-on-Chip (MPSoCs), which offer both performance and energy efficiency. However, ensuring the safety compliance of such complex systems remains a major challenge. The software frameworks used to implement AD functionalities—typically integrating Artificial Intelligence (AI) algorithms—are not designed following a safety-driven development processes, and their non-deterministic behavior conflicts with the strict determinism required by safety standards. This thesis addresses these challenges by developing Verification and Validation (V&V) solutions that improve the safety compliance of AD frameworks, with a particular focus on performance-related aspects.The thesis begins by analyzing the main sources of non-determinism in AD systems across three layers: algorithmic, software architectural, and hardware platform. While variability exists in all layers, the software architecture layer is identified as a key contributor to the overall unpredictability. It not only introduces its own sources of variability but also amplifies those inherited from the other layers. This makes software architecture an effective focal point to improve system determinism and safety assurance.At the foundational level, the thesis addresses the challenge of unit testing within already-integrated AD frameworks, using the open-source Apollo AD framework as a case study. Due to tight coupling and data dependencies among its modules, Apollo does not easily support independent module validation. To enable proper verification of software units, the thesis proposes a systematic methodology to isolate, modify, and reconfigure Apollo modules into standalone, testable units, thus reintroducing unit-level testing capabilities into a complex, AI-based AD framework.The work advances toward system-level safety assurance through the development of dynamic and execution views of Apollo. Dynamic views describe the interactions among software components, linking safety requirements with their implementation and validation tests. However, these views alone fail to capture the concurrent behavior and execution parallelism of the system, which are crucial for verifying performance-related safety requirements. To fill this gap, the thesis introduces execution views, which complements dynamic views by integrating runtime information gathered from execution tracing on MPSoC platforms. Execution views enhance the observability of resource usage, timing behavior, and concurrency, allowing both improved testing and optimized hardware utilization—key aspects for reducing cost and ensuring safety.Finally, the thesis addresses the timing behavior and variability across software components. It identifies, formalizes, and applies a comprehensive set of timing-related metrics capable of capturing inter-module interactions and end-to-end latency properties in AD applications. Traditional timing metrics, such as worst-case execution and response times, fail to capture the interdependencies between components in systems like Apollo. By adopting complementary metrics such as maximum reaction time and maximum time displacement, the proposed approach provides deeper insights into timing dependencies, enabling early detection of timing anomalies and improving validation confidence.Overall, this thesis provides a set of methodologies and tools to improve the V&V of AD software from a safety-performance perspective. The proposed contributions bridge the gap between high-performance AI-based software and the stringent determinism required by safety standards. These advances support the systematic assurance of safety in AD frameworks, ultimately contributing to the reliable and certifiable deployment of autonomous vehicles on high-performance embedded platforms.
  

DOCTORAL DEGREE IN COMPUTING

• NJOKU, UCHECHUKWU FORTUNE: Towards Effective and Interpretable Many-Objective Feature Selection in Machine Learning
  
  Author: NJOKU, UCHECHUKWU FORTUNE
  Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
  Programme: DOCTORAL DEGREE IN COMPUTING
  Department: Department of Computer Science (CS)
  Mode: Change of supervisor
  Deposit date: 04/12/2025
  Deposit END date: 18/12/2025
  Thesis director: ABELLO GAMAZO, ALBERTO | BILALLI, BESIM | BONTEMPI, GIANLUCA
  Thesis abstract: Effective Machine Learning (ML) requires more than just accurate models; it also demands consideration of factors such as model complexity, fairness, and other task-specific requirements. Fulfilling these requirements begins at the data level by selecting features that con-tribute to addressing these concerns. This can benefit from a many-objective optimization approach to Feature Selection (FS).This thesis, therefore, studies Many-Objective Feature Selection (MOFS) and contributes to the development of efficient and responsible ML solutions. However, due to the large number of MOFS solutions, it comes with an interpretability challenge. Therefore, we also aim to propose a methodology for tackling this limitation of MOFS.Although FS has been long researched, previous work (on both filter and wrapper methods) has failed to address this gap by focusing only on one or at most two objectives. Also for the interpretability of FS results, no methodological approach has been proposed and rather a basic tabular representation has been used.We propose a framework that uses non-dominated sorting genetic algorithms to balance important and often conflicting objectives for FS. In particular, more than four to fifteen objectives could be considered with this method. For interpretability, our proposed methodology consists of six steps that consider three viewpoints: objectives, solutions, and variables (i.e., features).To achieve the research goal, we follow a structured approach: first, an extensive literature review that establishes the state-of-the-art and identifies open challenges. Next, empirical analyses of single-objective filter and wrapper methods, as well as multi-objective wrapper methods, are conducted to assess their strengths and limitations. Our MOFS framework is then proposed and evaluated through multiple experiments, including its application to fairness in ML. Finally, the interpretability methodology is instantiated as an interactive dashboard, which is validated through an experimental study involving 50 participants, with statistical analysis to assess its effectiveness.The findings highlight that no single FS method is universally optimal; instead, the best approach depends on dataset characteristics, task requirements, and objectives. While filter methods are computationally efficient and wrapper methods enhance model performance in single-objective settings, the proposed MOFS framework successfully balances multiple conflicting indicators related to performance, complexity, and fairness. Moreover, the interpretability methodology proved essential in helping data scientists to better understand MOFS results, enabling informed decision-making in FS.
  

DOCTORAL DEGREE IN GEOTECHNICAL ENGINEERING

• ALONSO, MATÍAS: Hydro-mechanical modelling of a sealing concept for a deep geological radioactive waste repository
  
  Author: ALONSO, MATÍAS
  Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
  Programme: DOCTORAL DEGREE IN GEOTECHNICAL ENGINEERING
  Department: Department of Civil and Environmental Engineering (DECA)
  Mode: Normal
  Deposit date: 15/12/2025
  Deposit END date: 08/01/2026
  Thesis director: VAUNAT, JEAN | OLIVELLA PASTALLE, SEBASTIAN
  Thesis abstract: Deep Geological Disposal (DGD) has emerged as the most viable solution for the final disposal of radioactive waste, offering the potential for the permanent containment and isolation of waste from the biosphere over extended timescales. Several countries have made significant progress in developing Deep Geological Repository (DGR) concepts for the permanent disposal of such waste. The long-term safety of these facilities relies primarily on the host rock—the natural barrier that plays the central role—supplemented by engineered components collectively referred to as the engineered barrier system (EBS). The EBS includes containers, backfills, buffers, and other structures designed to ensure favourable conditions for the long-term isolation of radioactive waste. The design, performance, and safety assessment of a DGR—and particularly of its EBS components—are therefore essential for the sustainable development of nuclear energy, making their study a key research area within geotechnical engineering.In this context, the main objective of this research is to contribute to the understanding and assessment of the long-term performance of a large-diameter sealing concept developed within the framework of the Cigéo project, led by the French National Radioactive Waste Management Agency (Andra). To achieve this objective, a multi-scale and multi-step numerical modelling strategy has been adopted. The approach combines detailed material characterisation with advanced constitutive modelling of the expansive core, backfill materials, and host rock, accounting for features such as inherent anisotropy and double structure. The modelling framework incorporates coupled hydro-mechanical processes, enabling the analysis of key phenomena such as the natural hydration of the sealing core, the development of swelling pressure, the resaturation and recompression of the excavation-damaged zone (EDZ), the global equilibrium of the sealing system, and the potential deconfinement of the sealing core and its associated loss of swelling capacity. The simulations address the complexity of the problem by integrating large-scale three-dimensional geometries, advanced constitutive formulations, and critical geometric details at the decimetre scale. These challenging simulations provide valuable insights into the performance and long-term integrity of the sealing structures, establishing a robust framework and a powerful tool to enhance the understanding of the behaviour of these EBS, contributing to the optimisation of repository design and safety.
  
• RODRÍGUEZ ROMERO, CARLOS EDUARDO: Analysis of coupled hydro-mechanical processes in double-structure geomaterials for nuclear waste storage
  
  Author: RODRÍGUEZ ROMERO, CARLOS EDUARDO
  Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
  Programme: DOCTORAL DEGREE IN GEOTECHNICAL ENGINEERING
  Department: Department of Civil and Environmental Engineering (DECA)
  Mode: Normal
  Deposit date: 04/12/2025
  Deposit END date: 18/12/2025
  Thesis director: VAUNAT, JEAN | GENS SOLE, ANTONIO
  Thesis abstract: The safe long-term isolation of high-level radioactive waste requires engineered barriers capable of maintaining low permeability and mechanical stability under complex thermo-hydro-mechanical (THM) conditions. Among candidate materials, compacted bentonite exhibits a distinctive double-structure behaviour, governed by the coexistence of micro- and macro-porous domains. This thesis focuses on the analysis of coupled hydro-mechanical processes in double-structure geomaterials, with particular attention to bentonite mixtures of blocks and pellets, as used in buffer systems for deep geological repositories. The research first reviews the geomechanical basis of double-structure soils and identifies the experimental evidence supporting their dual-porosity nature. A constitutive THM framework is then developed, extending the existing double-structure formulation to incorporate: (i) the parameter ακ to control microstructural deformation; (ii) a fabric-dependent structuration law to represent the memory and degradation of compression; and (iii) frictional resistance at block–pellet and block–wall interfaces.The model was implemented and calibrated using laboratory and mock-up experiments from the BEACON project, including the MGR22, MGR23, and MGR27 experiments, the EPFL path-dependent tests and the POSIVA test. Numerical simulations successfully reproduced the evolution of swelling pressure, void ratio, dry density, water content and water intake observed experimentally. The results confirmed that friction plays a decisive role in the redistribution of stresses between pellets and blocks, while microstructural evolution governs the long-term homogenisation process. The enhanced formulation captured partial density homogenisation and the persistence of microstructural porosity, in agreement with laboratory observations.Overall, the thesis provides an improved understanding of the coupled hydro-mechanical behaviour of double-structure bentonites and proposes a robust constitutive framework capable of reproducing their key features under repository-relevant conditions. The work highlights the necessity of considering both microstructural evolution and frictional effects in predictive models for bentonite barriers, thus contributing to the reliability of long-term safety assessments of deep geological repositories.
  

DOCTORAL DEGREE IN PHOTONICS

• ARRÉS CHILLÓN, JAVIER: Application to Sensing, Imaging, and Cooling of Ultra-Thin Metal Films and Derived Nanostructured Glass Surfaces
  
  Author: ARRÉS CHILLÓN, JAVIER
  Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
  Programme: DOCTORAL DEGREE IN PHOTONICS
  Department: Institute of Photonic Sciences (ICFO)
  Mode: Normal
  Deposit date: 04/12/2025
  Deposit END date: 18/12/2025
  Thesis director: PRUNERI, VALERIO
  Thesis abstract: The continuous evolution of optoelectronic systems responds to the demand for higher efficiency, speed, and sensitivity. A key strategy is to modify material dimensions at the nanoscale, which alters their optical, electrical, and thermal properties and enables new functionalities.A prominent example is ultra-thin metal films (UTMFs), with thicknesses below 10 nm, which exhibit properties different from thicker metal layers. This thesis explores the use of gold (Au) UTMFs deposited on copper oxide (CuO) seed layers, fabricated with industrial techniques such as physical vapor deposition (PVD). These ultra-thin films enable continuous and ultrasmooth surfaces, as well as tunable properties through optical or electrical processes.The potential of these UTMFs in electrochemical sensors based on self-assembled monolayers (SAMs) is demonstrated. The results show that thinner films respond more rapidly to SAM formation, and that biotin functionalization enables the detection of streptavidin through measurable resistance changes.The optical interaction between UTMFs and fluorophores is also investigated, focusing on fluorescence quenching caused by non-radiative energy transfer. Experiments reveal the dependence on film thickness and fluorophore–metal separation, confirming that these films can enhance the signal-to-noise ratio in fluorescence imaging of stained bacteria.Finally, glass surfaces are nanostructured with nanopillars (NPs) generated via thermally dewetted UTMF masks and subsequent etching. These surfaces exhibit unique optical properties: anti-reflective coatings in the visible range and enhanced infrared emissivity. Moreover, they are combined with thin polymer coatings to preserve visible transparency while improving the efficiency of passive radiative cooling (PRC). Results confirm that nanostructured glass surfaces dissipate more heat than flat ones, opening opportunities in solar panels, displays, and windows.This thesis therefore demonstrates the potential of Au UTMFs and nanostructured glass surfaces for the development of chemical sensors, advanced optical microscopy techniques, and radiative cooling applications.
  
• TYULNEV, IGOR: Investigation and Control of Phase Transitions by Ultrafast Strong-field Techniques
  
  Author: TYULNEV, IGOR
  Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
  Programme: DOCTORAL DEGREE IN PHOTONICS
  Department: Institute of Photonic Sciences (ICFO)
  Mode: Normal
  Deposit date: 10/12/2025
  Deposit END date: 24/12/2025
  Thesis director: BIEGERT, JENS
  Thesis abstract: This work presents the experiments and results on the application of mid-infrared laser sources towards condensed matter systems for the study and control of manybody interactions within material phases and at phase boundaries. Utilizing the decades in know-how and development of intense, few-cycle waveforms at high repetition rates, the here demonstrated applications leverage the mid-infrared wavelengths to study and control strong-field phenomena at ultrafast time-scales and across phase transitions. To this end non-linear techniques are employed to extend the source capabilities towards a variety of driving and probing wavelengths, meanwhile tailoring spin-angular momentum multi-color beams as driving fields with unique patterns. With strong-field driven dynamics happening at sub-cycle time scales, techniques such as high harmonic generation (HHG) are applied to a variety of materials which undergo electronic and structural transitions. For bulk transition metal dichalcogenides, as the investigated MoS2, the induced spatial and temporal symmetry breaking from a tailored trefoil-shaped strong-field allowed the detection of valley polarization, i.e. a carrier population imbalance between neighboring bandgap extrema. The specific control of the energy bands at these sites, first, allows the realization of a valley switch to be used for optical computing, and second, realizes a hybrid system of light and matter with band topology akin to the Haldane model, which paves the way towards field-induced and controlled topological phase transitions in two-dimensional materials. Furthermore, the field-induced currents and the emerging harmonics are used to probe the potential landscape of the lattice and therefore, simultaneously detect signatures of the crystal and band structure encoded in a static spectrum. Interference within the spectra further reveal the underlying electron-hole dynamics and timings. In high-temperature superconducting ceramics like YBCO, the temperature induced changes in electronic properties are also sensitively detected via HHG, even for more elusive material phases. Meanwhile higher order transitions like the correlated charge density wave (CDW) phase shows a mixture of electronic and structural changes in the HHG crystallography as investigated in TiSe2. The macroscopic and nonlinear approach yields major changes in the harmonic spectra even from small changes in e.g. atom displacement and identifies phase anisotropies which eluded conventional or microscopic techniques.
  

DOCTORAL DEGREE IN SIGNAL THEORY AND COMMUNICATIONS

• GIL DÍAZ, CRISTINA: Characterization of cirrus clouds and dust aerosols with remote sensing: application of radiative transfer models for the study of their radiative effects
  
  Author: GIL DÍAZ, CRISTINA
  Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
  Programme: DOCTORAL DEGREE IN SIGNAL THEORY AND COMMUNICATIONS
  Department: Department of Signal Theory and Communications (TSC)
  Mode: Article-based thesis
  Deposit date: 09/12/2025
  Deposit END date: 22/12/2025
  Thesis director: SICARD, MICHAEL
  Thesis abstract: Clouds and aerosols are key modulators of the Earth’s radiative balance, yet their interactions remain among the largest sources of uncertainty in climate projections. This Ph.D. thesis investigates aerosol–cloud–radiation processes at mid-latitudes, with emphasis on cirrus clouds and mineral dust, by combining long-term ground-based lidar measurements, radiative transfer modelling, and regional climate simulations.First, a multi-year dataset of MPLNET lidar measurements in Barcelona was analyzed to characterize the geometrical and optical properties of cirrus clouds and to quantify their direct radiative effect. Cirrus occurrence was high, with marked seasonal variability. Distinct radiative behaviours were identified: at nighttime, cirrus clouds warm both top-of-the–atmosphere and bottom-of-the–atmosphere, while during at daytime they consistently warm top-of-the-atmosphere and predominantly cool bottom-of-the-atmosphere.Second, the semi-direct radiative effects of Saharan dust during a coupled dust and heatwave event were assessed with a regional climate model over the Iberian Peninsula. Results highlighted the importance of spectral nudging for an accurate simulation and showed that dust absorption modifies thermodynamic profiles, cloudiness, and the surface energy balance, thereby partially mitigating heatwave impacts. These responses were spatially heterogeneous, reflecting the strong dependence of dust–radiation interactions on dust distribution and meteorological conditions.Third, the role of the dust giant mode and the dust conversion factors for calculating cloud condensation nuclei and ice-nucleating particle concentrations were examined. Incorporating a synthetic giant mode significantly improved the agreement with reference datasets for the dust direct radiative effect, despite inherent uncertainties and idealized assumptions. In addition, dust conversion factors were derived from AERONET and MPLNET lidar measurements, demonstrating the potential of lidar to provide vertically resolved proxies for aerosol indirect effects.
  

DOCTORAL DEGREE IN STRUCTURAL ANALYSIS

• SLIMANI, MEHDI: Computational strategies for time-accurate simulation of part-scale LPBF
  
  Author: SLIMANI, MEHDI
  Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
  Programme: DOCTORAL DEGREE IN STRUCTURAL ANALYSIS
  Department: Department of Civil and Environmental Engineering (DECA)
  Mode: Article-based thesis
  Deposit date: 15/12/2025
  Deposit END date: 08/01/2026
  Thesis director: CHIUMENTI, MICHELE | CERVERA RUIZ, LUIS MIGUEL
  Thesis abstract: The qualification of MAM (Metal Additive Manufacturing) processes remains a majorchallenge due to the complex thermo-mechanical phenomena involved.The process is driven by a small moving heat sourcethat generateshighly localized, transient thermal gradientsand induces thermal strains.As these strains are constrained bythe surrounding material,residual stresses and warpage develop,causing part distortion or even failure.Accurate modeling is essential for understanding the underlying physics, aswell as for reliable process qualification and parameter optimization.However,such simulations are computationally expensive due to the small size of theheat source, which introduces disparate spatial scales,and its continuous motion, which gives rise to equally disparate temporalscales.The need to simultaneously resolve these scalesrenders high-fidelity part-scale simulations prohibitively expensive.This thesis contributes to the field of MAM modeling on both the appliedand methodological fronts. On the applied side, methods for warpage and stressmitigation are investigated in both DED (Directed Energy Deposition) and LPBF (Laser Powder Bed Fusion) processes, includinga novel substrate design strategy for DED that significantlyreduces residual stresses, and a modeling framework to capturerecoater–induced build failure in LPBF.On the methodological front, the thesis focuses on developing efficientstrategies for high-fidelity part-scale simulations of LPBF processes,with particular emphasis on overcoming the disparity of temporal scales.WhileAMR (Adaptive Mesh Refinement) has become a popular approach to address the challenge of disparatespatial scales, uniform time stepping remains the standard approach in the field.For centimeter-scale parts, this can require hundreds of millions of time-steps,making such simulations computationally unfeasible.Commonly used strategies to alleviate this issue involveextreme simplifications of the thermal model,such as lumping multiple tracks or layersinto a single time-step.Effectively, this eliminates the small scales associated with the moving heat sourcebut compromises the model's predictive accuracy,requiring additional calibration.Two methods are proposed to address the temporal-scale disparity withouteliminating the underlying small scales: the advected subdomain and aRobin–Robin substepping scheme, both designed to preserve modelfidelity while drastically reducing computational cost.The advected subdomain method attaches a moving mesh to the laser. Bysolving the thermal problem in the reference frame of the heat source, thetransient dynamics near the melt pool become quasi-steady, allowing the use ofsignificantly larger time-steps.Substepping divides the domain into regions that evolve with differenttime-steps:finer steps are applied locally around the moving heat source, while larger stepsare used away from it.The developed Robin-Robin coupling scheme proves robust andensures mesh-independent convergence between the regions.These methods and their components are systematically evaluated throughnumerical analysis, benchmarked against standard approaches, and validatedagainst experimental data. Furthermore, they are combined to compound theirrespective benefits.Together, these contributions advance numerical MAM modeling,thereby improving the computational efficiency of high-fidelity simulationsand enabling reliable process qualification and optimization.
  

DOCTORAL DEGREE IN URBAN AND ARCHITECTURAL MANAGEMENT AND VALUATION

• SIFUENTES MUÑOZ, BLANCA CAROLINA: Transformación urbana y movilidad sostenible: construyendo una Barcelona car-free
  
  Author: SIFUENTES MUÑOZ, BLANCA CAROLINA
  Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
  Programme: DOCTORAL DEGREE IN URBAN AND ARCHITECTURAL MANAGEMENT AND VALUATION
  Department: Department of Architectural Technology (TA)
  Mode: Normal
  Deposit date: 15/12/2025
  Deposit END date: 08/01/2026
  Thesis director: ROCA CLADERA, JOSE NICASIO | ARELLANO RAMOS, BLANCA ESMARAGDA
  Thesis abstract: The configuration of contemporary cities has been deeply shaped by the hegemony of the automobile as a structuring axis of territory, mobility, and public space. This model, consolidated since the mid-20th century, has led to dispersed, exclusionary, and unsustainable urban forms, limiting quality of life and hindering the creation of more equitable and resilient environments. In response, critical approaches have emerged advocating for a paradigm shift toward people-centered cities, the right to the city, and sustainable mobility.In this context, this doctoral thesis aims to construct prospective scenarios for a car-free Barcelona by 2050, through a structural and multiscalar analysis of its mobility system, urban planning, and use of public space. A mixed-methods approach is adopted, integrating six methodological lines: (1) collection and preprocessing of mobility data from the Barcelona Metropolitan Area (AMB); (2) exploratory factor analysis (EFA) on a longitudinal AMB database; (3) trend analysis using regression and ARIMA models to project modal shifts; (4) comparative analysis of Amsterdam and Copenhagen as international car-free transition benchmarks; (5) expert consultation through a disaggregated Delphi method; and (6) construction of contrasted future scenarios.The results identify latent structures in the mobility system, tensions between urban policies and actual mobility practices, and institutional challenges linked to multilevel governance. The developed scenarios outline alternative urban futures, from continuity-based models to deep transformations, highlighting their implications in terms of equity, sustainability, and the right to the city.This research provides an original contribution by integrating approaches from sustainable mobility, prospective planning, and multiscalar analysis. Its findings guide the formulation of public policies and urban strategies toward more just, healthy, and sustainable post-car cities. Ultimately, it proposes conceptual and methodological tools to rethink urbanism through the lens of deep transformation in the face of climate, social, and territorial uncertainty.