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Theses authorised for defence

  • MARTÍNEZ MÉNDEZ, MIGUEL: Relación entre la Cultura Organizacional dominante y los Estilos de Liderazgos en la Policía de Puerto Rico
    Author: MARTÍNEZ MÉNDEZ, MIGUEL
    Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
    Programme:
    Department: Department of Engineering Design (PE)
    Mode: Normal
    Deposit date: 25/06/2014
    Reading date: pending
    Reading time: pending
    Reading place: pending
    Thesis director: FIGUEROA GONZÁLEZ, JOSE MANUEL
    Committee:
         PRESIDENT: TEJEDOR CALVO, SANTIAGO
         SECRETARI: GONZALEZ BENITEZ, MARIA MARGARITA
         VOCAL: ARZAMENDI SÁEZ DE IBARRA, JESÚS
    Thesis abstract: Historically, theorists have attempted to develop an effective leadership model from the great man theory to present day philosophical leadership concepts. Present day theorists continue to identify and define transformational leadership as an effective leadership style in which leaders motivate subordinates' commitment to organizational goals, vision, and mission by empowerment them to take action in pursuit of organizational effectiveness. This effort to increase organizational effectiveness is also evident in industrial-organizational psychology's history with the work of the Gilbreths (1917) and Henry Ford 1913 on the USA vehicle industry Shenhow (1999).This paper investigates the relationship between organizational culture and the style of leadership in the Puerto Rico Police Department. Organizational culture is often an important factor influencing the competitive strength of any organizational entity. Leadership is also a critical component in the success an organization. It is important to understand how these two powerful determinants of organizational performance, culture and leadership, affect each other. Research determining that specific types of organizational culture favor particular styles of leadership is important as it aids organizational leaders to identify which styles of leadership are more likely to be successful in their culture. Furthermore, organizations wishing to change leadership styles may have to first modify their culture to support different leadership styles. This study uses the Competing Values Framework to define the organizational culture as clan, adhocracy, hierarchy, or market. Leadership style is defined as transformational, transactional, or laissez faire. Organization culture is measured using the Organizational Culture Assessment Instrument and the leadership style is determined by the MLQ 5X survey. Pearson's correlation and regression is used to determine the relationship between the variables. The results of this study indicate there is not a significant relationship between the dominant types of organizational cultures and leadership styles. Transactional, transformational and laisser-faire leadership styles were not significant statistical correlational found in hierarchy cultures.

DOCTORAL DEGREE IN AEROSPACE SCIENCE AND TECHNOLOGY

  • CAAMAÑO ALBUERNE, MARÍA: Network-based ionospheric gradient monitoring to support ground based augmentation systems
    Author: CAAMAÑO ALBUERNE, MARÍA
    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 AEROSPACE SCIENCE AND TECHNOLOGY
    Department: Department of Physics (FIS)
    Mode: Normal
    Deposit date: 22/04/2022
    Reading date: 12/07/2022
    Reading time: 11:00
    Reading place: FME- Mòdul C3, Sala 204 (Biblioteca Dept. Matemàtiques), Campus Barcelona Nord UPC.
    Thesis director: SANZ SUBIRANA, JAIME | JUAN ZORNOZA, JOSE MIGUEL
    Committee:
         PRESIDENT: PULLEN, SAMUEL PHILLIP
         SECRETARI: ROVIRA GARCIA, ADRIÀ
         VOCAL: SOKOLOVA, NADEZDA
    Thesis abstract: The Ground Based Augmentation System (GBAS) is a local-area, airport-based augmentation of Global Navigation SatelliteSystems (GNSSs) that provides precision approach guidance for aircraft. It enhances GNSS performance in terms of integrity,continuity, accuracy, and availability by providing differential corrections and integrity information to aircraft users. Differentialcorrections enable the aircraft to correct spatially correlated errors, improving its position estimation. Integrity parameters enable it to bound the residual position errors, ensuring safety of the operation. Additionally, a GBAS ground station continuously monitors and excludes the satellites affected by any system failure to guarantee the system integrity and safety.Among the error sources of GNSS positioning, the ionosphere is the largest and most unpredictable. Under abnormalionospheric conditions, large ionospheric gradients may produce a significant difference between the ionospheric delayobserved by the GBAS reference station and the aircraft on approach. Such a spatially decorrelated ionosphere could lead tohazardous unbounded position errors if undetected. Conventional GBAS solutions to mitigate this threat assume that the ¿worstcase" ionospheric gradient ever observed in the relevant region is always present, which is a very conservative assumption. This approach, which relies on the conservative ionospheric threat models derived for GBAS, maximizes integrity, often at the expense of availability and continuity, especially in geographic areas with highly active ionosphere.As opposed to assuming a permanent ¿worst-case¿ gradient, I propose the Network GBAS concept, in which several reference stations collaborate to monitor for actual ionospheric gradients. This concept consists of two main steps. First, the network detects the anomalous ionospheric gradients, estimates the gradient parameters, and transmits this information to the GBAS stations installed in its coverage area. Then, the GBAS stations replace the ¿worst-case¿ gradient used to mitigate the ionospheric threat in current algorithms with the gradient information provided by the network. This approach reducesconservatism and leads to an improvement of the system availability without compromising user integrity.This thesis validated the performance of the detection and estimation algorithms with simulated and real ionospheric gradients from two different locations known for their high levels of ionospheric activity. One location was Alaska, where the analyzed real anomalous gradients were small in size but fast-moving; the other location was Brazil, dominated by large-but-slow anomalous gradients. This analysis led to the adaptation of the algorithms to work in challenging scenarios.The evaluation of the Network-GBAS concept compared in simulations the availability of a Category I (CAT I) GBAS station atthe Brazil location in two cases: assuming the conservative ionospheric threat model, and using the gradient informationprovided by the network. On a selected nominal day (i.e., with no significant ionospheric activity), availability improved from79.5% to 94.6% during the nighttime. On a selected active day, availability improved from 68.7% to 89.5% during the nighttime. During daytime, availability achieved 100% on both days.Results demonstrate that the Network-GBAS concept can significantly enhance CAT I GBAS availability in active ionosphericregions without compromising user integrity. Furthermore, by incorporating the information provided by the network into existing solutions, the Network-GBAS is compatible with existing algorithms and hardware, and thus should be certifiable if adapted to the characteristics of each region where GBAS is fielded.

DOCTORAL DEGREE IN ARCHITECTURAL, BUILDING CONSTRUCTION AND URBANISM TECHNOLOGY

  • TORRES LONDOÑO, NATALIA PAOLA: Domos Desplegables. Método geométrico a partir de polígonos regulares
    Author: TORRES LONDOÑO, NATALIA PAOLA
    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, BUILDING CONSTRUCTION AND URBANISM TECHNOLOGY
    Department: Department of Architectural Technology (TA)
    Mode: Normal
    Deposit date: 09/04/2022
    Reading date: pending
    Reading time: pending
    Reading place: pending
    Thesis director: SASTRE SASTRE, RAMON
    Committee:
         PRESIDENT: STEVENSON, CAROLINA MARGARITA
         SECRETARI: LACASTA PALACIO, ANA MARIA
         VOCAL NO PRESENCIAL: COCHO BERMEJO, ANA
    Thesis abstract: This research proposes a design method for deployable domes from the scissor-type system, starting from the geometry of regular polygons for its configuration. The geometry of the regular polygons inscribed in a circumference, allows to determine the general shape of an arch in the final state of the deployment, defining the number of necessary bars, the positioning of the holes, the distances of the points of articulation, the length of the bar and the necessary opening angle to obtain a specific geometry.Taking the arch as the main structural component for the configuration of domes, the proposed method allows to implement the correlated design with folding floor platforms and folding textile covers to achieve a simultaneous deployment between structure and enclosures.The study develops as part of the constructive viability, an assembly process based on the traditional system to erect arches and domes, that is, through the progressive semi-arches approximation from the floor, to midpoint, at a specific height, in this way, the advantage of deployable structures is used to raise the arches, optimizing assembly times and facilitating the execution method in deployable structures. The method viability and demonstration is verified through the construction of several scale prototypes developed during the investigation that expose the validity constructive, architectural and structuralFinally, the objective is to propose new spatial alternatives for deployable domes, through an interactive table that allows the user to explore different geometries of arches formed with the scissor-type system and applied to an enclosure with specific requirements for height, radius or length of bars.

DOCTORAL DEGREE IN BIOMEDICAL ENGINEERING

  • PALMIERI, FLAVIO: Serum Potassium Concentration Monitoring by ECG Time Warping Analysis on the T wave
    Author: PALMIERI, FLAVIO
    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 BIOMEDICAL ENGINEERING
    Department: Department of Automatic Control (ESAII)
    Mode: Normal
    Deposit date: 20/04/2022
    Reading date: 31/05/2022
    Reading time: 11:15
    Reading place: Sala d'Actes de la Facultat de Matemàtiques i Estadística (FME), Carrer de Pau Gargallo, 14, 08028 Barcelona
    Thesis director: GOMIS ROMAN, PEDRO | LAGUNA LASAOSA, PABLO
    Committee:
         PRESIDENT: CORSI, CRISTIANA
         SECRETARI: ROMERO PEREZ, DANIEL
         VOCAL: MAROZAS, VAIDOTAS
    Thesis abstract: End-stage renal disease (ESRD) patients demonstrate an increased incidence of sudden cardiac death (SCD) with declining kidney functioning as a consequence of blood potassium ([K+]) homeostasis impairment, which is restored by hemodialysis (HD) therapy. The clinically established method for the diagnosis of [K+] imbalance is blood tests, an invasive and costly procedure that limits continuous monitoring of ESRD patients. A non-invasive ambulatory index, able to quantify changes in [K+] level is an open issue. In this context, the electrocardiogram (ECG) and in particular, the T wave (TW) morphology, has been shown to be strongly correlated with [K+] imbalance. Therefore, the aim of this dissertation is to investigate and to propose TW-derived markers able to monitor changes in [K+] levels in ESRD patients undergoing HD. For that purpose, the time warping analysis, a technique that allows the comparison and quantification of differences between two different TW shapes, was investigated. The application of TW time warping based markers in monitoring [K+ ] variations (¿[K+]) and the derivation of a heart-rate corrected marker is proposed and compared with respect to two well-established ¿[K+]-related TW-based indexes. All the markers are evaluated in a single lead approach and after having emphasised the TW energy content through spatial transformation by Principal Component Analysis (PCA). Results demonstrate that the proposed biomarkers outperform the already proposed indexes, also proving that the use of PCA transformed lead generates markers with a higher correlation with ¿[K+] than the single lead approach. The possibility to improve markers robustness in the case of low signal-to-noise ratio ECGs, by spatially transforming the signal maximising the beat-to-beat TW periodicity criteria through the so-called Periodic Component Analysis (pCA), is then explored. pCA-based markers show superior performance during and after the HD than those obtained by PCA suggesting improved stability for continuous ¿[K+] tracking. The thesis studies also the application of regressions models to quantify ¿[K+] from pCA-based time warping markers. The accuracy of the regression models is evaluated by correlation and estimation error between the actual and the corresponding model-estimated ¿[K+] values, and the smallest estimation error is found for quadratic regression models. Being the time warping derived markers sensitive to TW boundary delineation errors, which may endanger their prognostic power, the advantages of using a weighting stage is investigated for their robust computation. The performance of two weighting functions (WF)s is tested and compared with respect to the control no weighting case, in simulated scenarios and in real scenarios (i.e. for [K+] monitoring and SCD risk stratification). No improvements in [K+] monitoring are found, probably due to the considerable marked [K+]-induced TW morphological changes. On the contrary, both simulation tests and SCD risk stratification analysis show that the proposed WFs can enhance the robustness of TW time warping analysis against TW delineation errors. In conclusion, this Doctoral Thesis confirms the hypothesis that enhanced perforce in ¿[K+] tracking and quantification can be achieved by analysing the overall TW morphology by time warping analysis. The simplicity of the technology, together with its low cost and ease of acquisition, should provide a new opportunity for TW analysis to reach standard clinical practice. Moreover, the use of WFs to minimise the undesired effects of TW delineation errors on the computation of time warping markers revealed a noticeable improvement of the SCD risk stratification power of time warping derived indexes.
  • RUBÍ SANS, GERARD: Development of an in vitro three-dimensional colorectal cancer model using cell-derived extracellular matrices
    Author: RUBÍ SANS, GERARD
    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 BIOMEDICAL ENGINEERING
    Department: (CEM)
    Mode: Article-based thesis
    Deposit date: 07/03/2022
    Reading date: 10/06/2022
    Reading time: 11:00
    Reading place: FME- Sala d'Actes de la Facultat de Matemàtiques i Estadística (FME), C. Pau Gargallo, 14. 08028 Barcelona
    Thesis director: ENGEL LOPEZ, ELISABET | MATEOS TIMONEDA, MIGUEL ÁNGEL
    Committee:
         PRESIDENT: ALCARAZ CASADEMUNT, JORDI
         SECRETARI: MAS MORUNO, CARLOS
         VOCAL: VENTOSA RULL, NORA
    Thesis abstract: Oncogenic pathologies are the second leading cause of death worldwide only after cardiovascular diseases. It is estimated that, by 2030, the number of patients diagnosed with this disease will increase by nearly a 70%, reaching 21 million cases per year (World Health Organization, WHO). From all these cases, only 35% of patients will successfully overcome the disease. Malignancies present a very heterogenous and unpredictable curse, often making the diagnosis and treatment, an arduous task for clinicians. In order to tackle the complexity of this disease, novel strategies have emerged, not only to investigate cancer cells, but also the cancer cell interactions with the other cell populations coexisting within the tumor microenvironment, as well as the extracellular matrix embedding all of them. Within the last 10 to 20 years, an increasing effort has been made to mimic native tumor properties in order to understand in vivo processes. Traditional 2D cultures are being replaced with more complex 3D scaffolds, where crucial aspects of cancer biology are replicated. Therefore, reproducing tumor architecture, biochemical composition and mechanical properties provides resident cells with multidimensional biochemical and mechanotransducive signaling cues, which results in an in vivo-like cell behavior. Based on the idea of providing complex 3D in vitro models to study cancer development and progression, I developed a 3D scaffold based on extracellular matrix deposited by mesenchymal cells, known as cell-derived extracellular matrix (CDM). In particular, I provided cells with a 3D microenvironment by culturing them on top of poly-lactic acid microcarriers. This 3D architecture, together with the addition of macromolecular crowders, enhanced cell ability to deposit their own extracellular matrix, ultimately resulting in the generation of cell-derived matrix scaffolds. The characterization of decellularized and microcarriers-free 3D matrices revealed a highly fibrillar structure based on its composition. Moreover, tailoring the production conditions of the matrices, I was able to obtain structures with varied composition as well as mechanical properties. Then, I repopulated CDMs with different colorectal cancer cell lines to generate a 3D in vitro cancer model. Repopulated CDMs showed a reduced cellular death in response to chemotherapeutic drugs, mimicking in vivo drug resistance provided by a biochemically and biomechanically complex 3D structure. Stromal cells, and in particular fibroblasts, are a key tumor microenvironment cell population that closely interacts with malignant cells. Cancer-associated fibroblasts (CAFs) play an important role in the remodeling and stiffening of the extracellular matrix surrounding tumor. In the present thesis, I studied the role of the progressively stiffer substrate upon normal fibroblasts and cancer-associated fibroblasts. Obtained results highlighted that, substrate/extracellular matrix stiffening is not enough for altered activation of healthy fibroblasts, but it plays an important role in the dysregulation of Hippo pathway in CAFs, a key signaling pathway involved in uncontrolled cell proliferation, tissue remodeling and abnormal growth processes. Finally, CDMs were repopulated with CAFs and colorectal cancer cell lines to study the interactions between the different cell types and the surrounding extracellular matrix scaffolds. Obtained results highlighted again the matrix remodeling potential of cancer-associated fibroblasts due to their interaction with malignant cells and the dysregulation of the Hippo pathway. In conclusion, this thesis highlights cell-derived matrices as a promising 3D in vitro model to study cancer disease development and progression, as CDMs mimic closely the native tumor microenvi-ronment properties. Further research in this field could potentially establish this platform as a fundamental tool for drug screening and target discovery assays.

DOCTORAL DEGREE IN BUSINESS ADMINISTRATION AND MANAGEMENT

  • NIETO CUBERO, JAVIER: Comercialización de innovaciones disruptivas. Actividades e indicadores clave en la fase de aceleración
    Author: NIETO CUBERO, 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 BUSINESS ADMINISTRATION AND MANAGEMENT
    Department: Department of Management (OE)
    Mode: Article-based thesis
    Deposit date: 02/05/2022
    Reading date: pending
    Reading time: pending
    Reading place: pending
    Thesis director: CONSOLACION SEGURA, CAROLINA MARIA
    Committee:
         PRESIDENT: HUERTAS GARCIA, RUBEN
         SECRETARI: GIL MARTIN, JOAN CARLES
         VOCAL: FORGAS COLL, SANTIAGO
    Thesis abstract: Context. The current industrial and corporate ecosystem is heavily conditioned both by the technological advances and by the existence of globalized and interconnected markets. Consequently, this makes it highly dynamic and volatile, with a high degree of uncertainty. Further polarization of this context is brought up by digitalization, revealing thus the need to develop disruptive innovations in order to keep long-term corporate competitiveness. Both technological viability and commercialization are the most significant challenges facing the development of disruptive innovations. Although it is one of the most critical phases, commercialization remains greatly understudied in this type of innovations (Aarikka-Stenroos and Lehtimaki, 2014; Marx et al., 2014). Authors such as Chiesa and Frattini (2011), Datta et al.(2013), Al Natsheh et al. (2015), or Tiberius et al. (2021) called for new research to be carried out in this area in order to better understand the processes of commercialization in disruptive innovations. Its potential findings will increase the chances of market success through the identification of the key factors to take into account and the activities to undertake during each of the phases of the innovation process. More specifically, authors such as Ford et al. (2011) claimed that a theoretical framework describing the acceleration phase is missing and academics such as Burg et al. (2012), and Gassman et al. (2012) pointed out that extensive research on the commercialization activities to undertake during this particular phase of the innovation is needed.Research topic. To investigate how the commercialization process of disruptive innovation works, in particular during the acceleration phase, in order to reveal intervention criteria to be implemented at this stage. Also, to improve the success rate of innovation projects being deployed in the market. The research will specifically focus on two organizational models of innovation: corporate ventures and spinoffs.Methodology. The research combines a systematic review of existing literature on commercialization within the context of the overall process of high uncertainty innovations, in particular in the acceleration phase, with a qualitative and exploratory methodology based on multiple case study (Yin, 2003). The sample analyzed comprises 20 spinoffs and 15 corporate ventures (derived from 8 multinational companies) belonging to a diversity of industrial sectors such as information technology, telecommunications, electronics, engineering services, consumer goods, health care and biotechnology.Findings. The main findings of the research are:¿ Defining the concept of commercialization in disruptive innovations and identifying influencing factors.¿ Designing a theoretical model for the commercialization of disruptive innovations based on the DIA model (O'Connor and de Martino, 2006).¿ Propose of a list of commercialization activities during each of the stages of the acceleration phase for corporate ventures and spinoffs, with the goal of improving the success rate during this phase. Identifying and comparing the different challenges facing corporate ventures and spinoffs.¿ Provide a list of verification activities and benchmarks to evaluate maturity and determine the right time to transfer disruptive projects from a corporate venture into a business unit.

DOCTORAL DEGREE IN CHEMICAL PROCESS ENGINEERING

  • ECHEVARRÍA DÍEZ-CANEDO, CARLOS: Integration of advanced wastewater treatment and reclamation technologies for organic micropollutants removal and promote water reuse
    Author: ECHEVARRÍA DÍEZ-CANEDO, CARLOS
    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: Article-based thesis
    Deposit date: 28/04/2022
    Reading date: pending
    Reading time: pending
    Reading place: pending
    Thesis director: CORTINA PALLAS, JOSE LUIS | VALDERRAMA ANGEL, CESAR ALBERTO
    Committee:
         PRESIDENT: SASTRE REQUENA, ANA MARIA
         SECRETARI: IBAÑEZ MENDIZABAL, RAQUEL
         VOCAL: TEIXIDO PLANES, MARC
    Thesis abstract: Climate change and overpopulation are responsible for more frequent droughts, and the imbalance in the water resources management leads to a greater competition in the exploitation of freshwater sources. The introduction of alternative water resources such as reclaimed water seems to be one of the most sustainable option from an economic and environmental point of view, compared with other alternatives such as seawater desalination or water transfer. Nevertheless, the wide implementation of water reuse is still far from its whole potential and faces different local barriers related to public awareness and governance.The presence of organic micropollutants (OMP) in the water cycle, specifically in the wastewater effluents intended to be reclaimed and reused, has generated concern in public authorities due to their uncertain effects in human health. During last decades, limited removal efficiencies in conventional wastewater and reclamation schemes were reported by several authors. In this line, innovation must bring suitable solutions to unblock current barriers. Novel advanced water reclamation technologies need to be demonstrated to guarantee the cost-effective removal of OMP, as well as provide solutions in terms of brine management or valorization. Moreover, it is necessary to propose educational and communication initiatives and address innovative governance models to achieve the economic feasibility of water reuse projects. Throughout three published articles (Chapter 3-5), this PhD thesis evaluates and compares from a technical and economic point of view different advanced municipal wastewater reclamation schemes to produce cost-effective reclaimed water to be reused. An industrial pilot-scale demonstration conducted in El Baix Llobregat WRP (Barcelona, Spain), removal efficiencies and costs of different advanced reclamation technologies focused on the removal of OMP were assessed, including PAC-MBR, ozonation-UV, PAC-UF, UF-RO and an innovative high-performance sorbent (CNM). On the other hand, tools to ease decision making in water reuse planning through a rapid estimation in costs need to be proposed. Cost curves for CAPEX and OPEX for different reclamation technologies will be also calculated and applied to estimate implementation costs of reusing urban reclaimed water for industrial uses in three different case studies in the Barcelona (Spain) area.The ultimate goal is to provide knowledge to overcome some of the identified barriers and contribute to a higher implementation of water reuse.

DOCTORAL DEGREE IN CIVIL ENGINEERING

  • REGALADO LÓPEZ, FRANCISCO JAVIER: Evaluación de proyectos de infraestructuras de transporte en dos etapas con impactos de no directa monetización
    Author: REGALADO LÓPEZ, FRANCISCO 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 CIVIL ENGINEERING
    Department: (DECA)
    Mode: Normal
    Deposit date: 04/04/2022
    Reading date: pending
    Reading time: pending
    Reading place: pending
    Thesis director: CAMPOS CACHEDA, JOSÉ MAGÍN | SAURI MARCHAN, SERGI
    Committee:
         PRESIDENT: MOURA BERODIA, JOSE LUIS
         SECRETARI: MARTINEZ REGUERO, ADRIANA HAYDEE
         VOCAL: GONZALO ORDEN, HERNÁN
    Thesis abstract: The constant and rapid population growth goes hand in hand with an increased demand for services that governments have the duty to satisfy with the problem of limited financial resources. Transport infrastructure is one of the ways to meet the need for movement of people and foster economic growth by connecting regions and cities for an exchange of goods and services. Select the right projects is crucial to achieving the stated objective, so a project evaluation process is conducted to determine whether the infrastructure alternative has sufficient net social benefit to be selected as a viable proposal. The main parameter for project evaluation is the discount of the economic costs and benefits generated by the infrastructure, commonly through a cost-benefit analysis, of different nature that are monetized to be able to perform the analysisThe costs and benefits, impacts that are considered within the cost-benefit analysis have evolved over the last twenty years, from consider only impacts that are fully convertible into monetary terms to environmental and social impacts that have had a great effort of study to achieve their quantification and monetization. There might be impacts that are more difficult to quantify and monetize in project evaluation, which have had a great research work as shown in the scientific literature to be considered in the evaluation of transportation infrastructure projects.We have reached a stage in the evaluation of projects in which we are understanding how to quantify these types of impacts without market value, but we still have the problem of being able to integrate them into the cost-benefit analysis due to the allocation of their price. The importance of these impacts is demonstrated through scientific literature, so it is necessary to find a way to consider them in the evaluation of infrastructures.Finally, a two-stage proposal is presented to consider impacts without market value within project evaluation. In the first stage, the impacts of the infrastructure are identified, the impacts with market value are quantified and discounted. In the second stage, a function is constructed with the results of the net present value of each monetized impact and the impacts without market value, using a linear programming problem to find the maximum benefit delivered by the project alternative. The solution of the problem delivers the absolute prices so that the total net value of the alternative project can be found. In addition, it distinguishes the project alternatives that provide the greatest social benefit with the inclusion of the impacts with no market value.
  • RIBA PORRAS, SERGI: Anàlisi de susceptibilitat torrencial en conques d¿alta muntanya a partir de la proposta de paràmetres indicadors. Construcció d'una base de dades multidisciplinària per al desenvolupament d'una zonificació de perillositat torrencial. Cas específic d¿Andorra
    Author: RIBA PORRAS, SERGI
    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: (DECA)
    Mode: Normal
    Deposit date: 25/04/2022
    Reading date: 14/06/2022
    Reading time: 11:00
    Reading place: ETSECCPB VIDEOCONFERENCIA Estat alarma Covid-19: https://meet.google.com/zob-pezk-nsc
    Thesis director: GOMEZ VALENTIN, MANUEL
    Committee:
         PRESIDENT: LOPEZ ALONSO, RAUL
         SECRETARI: HURLIMANN ZIEGLER, MARCEL
         VOCAL NO PRESENCIAL: NANIA ESCOBAR, LEONARDO SANTOS
    Thesis abstract: Over the last 40 years, in Europe in general and in many mountainous regions in particular, there have been major instances of severe flood episodes (more than 100) which have resulted in more than 700 deaths and billions of euros in economic losses. At European level, we can point out the floods of the Danube and the Elbe rivers in the summer of 2002. At a more specific level, in mountain areas and therefore on a more regional scale, we can mention the destruction caused by torrential phenomena, such as the floods of Andorra 1982, the tragedy of Camping las Nieves in Biescas in 1998 or the floods of the Garonne River in the summer of 2013.Thanks to this series of episodes and to the growing effects of climate change in mountain regions, both administrations and the general public have become aware of the dangers and risks associated with natural phenomena, and as such, with those related to river and torrential hydraulics. This awareness, combined with the technical advances experienced in recent years in the field of hydraulics, have led to the development of directives, laws and plans for the prevention of natural hazards (floods), which have subsequently had major repercussions in urban planning and therefore at a socioeconomic level.Despite the succession of regulations and directives applied in recent years (both in the state of Andorra and in general in countries with torrential problems), all of them have been mainly of a state nature and oriented to river flood plains; leaving mountain areas with torrential episodes, absent of cartography and associated regulations. The detection, zoning and evaluation of areas prone to triggering torrential phenomena, or current-type phenomena of dragging, are often difficult to predict if there are no evident and detectable geomorphological indications together with fieldwork, historic accounts, ortho photographs or aerial photographs of several years, and especially field data such as: precipitation history, readings of depths and flows, sedimentograms at the bottom of canals, sediment analysis in violent streams, analysis of hydraulic sections at drainage points, analysis of sediments deposited in alluvial fans etc.This lack of information or the limited and poorly structured treatment of the little information that is often available, makes it excessively complicated to know, study, and perform a zoning of such hazards associated with torrential dynamics, on a regional scale (for example of the Principality of Andorra on a scale of 1/5000) without having to develop detailed numerical studies and simulations.In this thesis, all those torrential parameters and indicators have been studied in detail, both at the basin and riverbed level, which may be related to the torrential dynamics, and therefore can give us clues as to the susceptibility of this occurrence of these types of events in certain areas. After analysing and classifying all the parameters potentially indicative of torrential dynamics in the basin and channel, a methodology has been proposed based on the grouping of the parameters treated in large analytical blocks: historical analysis, hydro-meteorological analysis, hydraulic analysis, geological -geotechnical analysis and morphometric analysis. The analysis and study of these large analytical blocks and all the parameters that compose them, have been elaborated with the ultimate goal of carrying out a statistical treatment and obtaining some decision criteria that allow us to create a qualitative zoning on a regional scale, depending on the potential danger of the exposed areas.The result obtained from zoning on a regional scale should also allow us to decide which phenomena have to be analyzed, according to their relevance, and how they are treated later and based on their nature, through fieldwork and numerical modelling.
  • VALDÉS ALONZO, GABRIEL ROLANDO: Identification of material properties and phase distribution of heterogeneous materials through data-driven computational methods: Towards an enhanced constitutive space
    Author: VALDÉS ALONZO, GABRIEL ROLANDO
    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: (DECA)
    Mode: Change of supervisor
    Deposit date: 06/05/2022
    Reading date: pending
    Reading time: pending
    Reading place: pending
    Thesis director: GARCIA GONZALEZ, ALBERTO | BINETRUY, CHRISTOPHE | LEYGUE, ADRIEN
    Committee:
         PRESIDENT: AMMAR, AMINE
         SECRETARI: ALFARO RUIZ, ICIAR
         VOCAL: REESE, STEFANIE
    Thesis abstract: Identifying the constitutive relations of materials is an essential task to understand their behavior. Classical methods like testing can be effective in understanding these relationships, but introducing models can lead to biased formulations and errors. Furthermore, not all constitutive relations can be determined directly by mathematical expressions or there might be parameters that we cannot obtain easily through common techniques.Data-Driven Identification (DDI), developed by Leygue et al. (2018), is an algorithm in which the constitutive relation of elastic materials is defined by a database of material points that need to be computed based on measured strain fields, applied forces and known geometry of tested samples of the material. The algorithm simultaneously estimates the corresponding values of the stress fields that emerge due to the deformations measured in the samples.In this thesis, we focus on departing from elasticity to cover more complex material behaviors with the DDI algorithm. In a first step, the method is applied to heterogeneous samples, where a post-process is performed with Correspondence Analysis to separate the different phases in a sample and identify their sepa-rated behavior. Then, DDI was also applied to linear viscoelastic materials, where an extended phase-space approach is used to account for the time dependence of the behavior. Finally, different variations of the algorithm are considered by combining DDI with different statistical techniques such as the Principal Component Analysis, in a search for speed and accuracy of the predictions through dimensionality reduction. Parallel to this, the method is tested in heterogeneous composite samples and compared to expected results obtained by classical methods.

DOCTORAL DEGREE IN COMPUTATIONAL AND APPLIED PHYSICS

  • FLORES GARCIA, JUAN CARLOS: Síntesis de nanoparticulas multifuncionalizadas tipo Core-Shell mediante rutas quimicas.
    Author: FLORES GARCIA, JUAN CARLOS
    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: 27/04/2022
    Reading date: pending
    Reading time: pending
    Reading place: pending
    Thesis director: CALDERON MORENO, JOSE MARIA | CRESPO ARTIAGA, DANIEL
    Committee:
         PRESIDENT: BATLLE GELABERT, XAVIER
         SECRETARI: PRADELL CARA, TRINITAT
         VOCAL: MOLERA I MARIMÓN, JUDIT
    Thesis abstract: In this thesis, the results ofdifferentcore-shell structures are presented after having been synthesized bythe modified Stober method, results of UV-Vis, SEM, TEM, XRD, among others, are shown, which determined the composition, morphology, and crystalline structure of particles of subm icron and even nanom etric size. Each chapter shows the results of the production and characterization of core-shell structures. Different core-shell structures with a varietyof morphologies were produced using a simple, robust and rapid chem ical m ethod, without the addition of coupling agents or surface modifications of the silica.In the first chapter, SiO2@ core-shell nanospheres ("50±10nm) were prepared, whose silver nanoparticles have sizes of - 4±2 nm in diameter. The preparation route is a modification ofthe Stober method, and im.olves the preparation of homogeneous silica spheres at room temperature, combined with the deposition of silver nanoparticles + in solution, by using water/ethanol mixtures, tetraethyl-orthos ilicate as Si source and silver nitrate as a source in a wet chem ical method in one pot, without the addition of coupling agents or surface modification, leading to the formation of homogeneous core­ shell nanospheres. The preparation and characterization ofSiO2@ core-shell nanospheres and also ofnal<ednanospheres, in the absence of silver, are presented, and the reaction mechanism s for the form ation of core-s hell structures are proposed.The second chapter presents three differ-ent silver nanoshells morphologies, produced on silica spheres using the módified Stober method, previous ly proposed, adding a second supply of silver nanoparticles, which leads to the form ation of silica core-silver nanoshells with silica cores from 50 to 600 nm in diameter and silver shells morphologies ranging from continuous, uniform and smooth layer about 10 nm thick, to rough surfaces of 3-5 nm nanoparticles to sharp spikes-like silver protrusions extending outward from the surface of the silica. We propose reaction mechanisms for the form ation of the different silica-silver core-shell nanostructures.In the third chapter we describe the production of a smooth and uniform silver outer nanoshell with a thickness of - 15 nm on submicrospheric silica, using a rapid and simple one pot chemical route. The reaction mechanisms proposed for the formation of silver nanoshell is the reactivity of silver nanoparticles with surface silanols at high pH, without added coupling¿. agents or surface m odification of silica, leading to the form ation of the continuous and hom ogeneous silver nanoshell on the silica spheres.The fourth chapter reviews the deposition of silver nanoparticles on the surface of silica us ing our simple, robust and fast chemical method without surface modification of silica or added coupling agents. The process was carried out at room temperature, in a single reaction process, using water/methanol mixtures, tetraethyl-orthosilicate as a Si source and silver nanoparticles (NPs). Using EDS, XRD, HRTEM and High Angle Annular Dark Field (HAADF) STEM characterization techniques, we have found the coexistence of silver NPs and silver oxide NPs anchored to the surface of subm icron silica spheres, with NPs predominating sizes around 2-3 nm approximately, and 20 NPs sizes over 1O nm.Each ofthese presented articles describe the preparation and characterization ofthe core-shell SiO2@ structures and propase the reaction mechanisms. Finally, we presented the analysis and conclusion ofthis work.
  • MORENO RAMOS, EDUARDO: Computer modeling of the polarity and amoeboid motion of living cells.
    Author: MORENO RAMOS, 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 COMPUTATIONAL AND APPLIED PHYSICS
    Department: Department of Physics (FIS)
    Mode: Normal
    Deposit date: 26/04/2022
    Reading date: 30/05/2022
    Reading time: 10:30
    Reading place: FIB - AULA B42012. Cmpus nord UPC
    Thesis director: ALONSO MUÑOZ, SERGIO
    Committee:
         PRESIDENT: RAMIREZ DE LA PISCINA MILLAN, LAUREANO
         SECRETARI: IBAÑES MIGUEZ, MARTA
         VOCAL: BUCETA FERNÁNDEZ, JAVIER
    Thesis abstract: Cell motility is important in many biological processes. Some examples relay in epidermal cells moving towards lesions during wound healing, neutrophils cells migrating towards sites of bacterial infection as part of the immune response, or sperm cells following chemical gradient to reach the ovum.Migration is a process observed in both, prokaryotes and eukaryotes cells. There exist many different mechanisms of migration depending on the particular cell, such as flagella, amoeboid, crawling or gliding motility. This work focus on the mathematical description of amoeboid crawling-like movement which is one of the most common type of locomotion in eukaryotic cells.Motility involves a network of interactions among multiple biochemical components. For example, before moving, cells produce an accumulation of proteins/lipids at the membrane in response to an external signal. This process is known as polarization. Next step is the activation of the cytoskeleton, which is the responsible of the locomotion of the cell. Consequently, actin microfilament network forming the cytoskeleton, pushes the membrane and triggers the formation of pseudopods, blebs or filopodia giving rise to the motion of the cell.One well studied system for this purpose is the amoeba Dictyostelium Discoideum, which is a eukaryotic cell that moves in presence (chemotaxis) or absence of external signals. Experiments show that Dictyostelium Discoideum present different shapes during motion, perform directed motion inside micro channels, and interact/trasport with micro-objects like small beads.In this work, a mathematical nonlinear reaction-diffusion model in combination with a dynamic phase field is proposed to reproduce different motility scenarios as amoeboid and fan-shape. Experimental data related with the dynamics of Dictyostelium Discoideum were supplied by the Biological Physics Group at the University of Potsdam. A comparison between the numerical simulations and live cell experiments of D. Discoideum cells under different developmental conditions permits the optimization of the model.Alternatively, the model is extended to analyze the effects of the formation of clusters by the interaction with a group of cells and when a single cell is confined inside a microchannel.Two more complex biochemical models that take into account a more detailed dynamics of the intracellular reactions of D. Discoideum cells were also coupled to a dynamic phase field.This work produces a computational synthetic cell that mimic the dynamics of experimental cells. The use of numeric methods and mathematical models helps with the understanding of the biological process involved in cell locomotion.

DOCTORAL DEGREE IN COMPUTER ARCHITECTURE

  • BARZEGAR, SIMA: Autonomous and reliable operation of multilayer optical networks
    Author: BARZEGAR, SIMA
    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: (DAC)
    Mode: Article-based thesis
    Deposit date: 25/04/2022
    Reading date: 03/06/2022
    Reading time: 11:00
    Reading place: FIB Sala d'Actes Martí Recober - B6 - FIB UPC Campus nord
    Thesis director: VELASCO ESTEBAN, LUIS DOMINGO | RUIZ RAMÍREZ, MARC
    Committee:
         PRESIDENT: SHARIATI, MOHAMMAD BEHNAM
         SECRETARI: JUNYENT GIRALT, GABRIEL
         VOCAL: CASTRO CASALES, ALBERTO ANDRÉS
    Thesis abstract: This Ph.D. thesis focuses on the reliable autonomous operation of multilayer optical networks.The first objective focuses on the reliability of the optical network and proposes methods for health analysis related to Quality of Transmission (QoT) degradation. Such degradation is produced by soft-failures in optical devices and fibers in core and metro segments of the operators¿ transport networks. Here, we compare estimated and measured QoT in the optical transponder by using a QoT tool based on GNPy. We show that the changes in the values of input parameters of the QoT model representing optical devices can explain the deviations and degradation in performance of such devices. We use reverse engineering to estimate the value of those parameters that explain the observed QoT. We show by simulation a large anticipation in soft-failure detection, localization and identification of degradation before affecting the network. Finally, for validating our approach, we experimentally observe the high accuracy in the estimation of the modeling parameters.The second objective focuses on multilayer optical networks, where lightpaths are used to connect packet nodes thus creating virtual links (vLink). Specifically, we study how lightpaths can be managed to provide enough capacity to the packet layer without detrimental effects in their Quality of Service (QoS), like added delays or packet losses, and at the same time minimize energy consumption. Such management must be as autonomous as possible to minimize human intervention. We study the autonomous operation of optical connections based on digital subcarrier multiplexing (DSCM). We propose several solutions for the autonomous operation of DSCM systems. In particular, the combination of two modules running in the optical node and in the optical transponder activate and deactivate subcarriers to adapt the capacity of the optical connection to the upper layer packet traffic. The module running in the optical node is part of our Intent-based Networking (IBN) solution and implements prediction to anticipate traffic changes. Our comprehensive study demonstrates the feasibility of DSCM autonomous operation and shows large cost savings in terms of energy consumption. In addition, our study provides a guideline to help vendors and operators to adopt the proposed solutions.The final objective targets at automating packet layer connections (PkC). Automating the capacity required by PkCs can bring further cost reduction to network operators, as it can limit the resources used at the optical layer. However, such automation requires careful design to avoid any QoS degradation, which would impact Service Level Agreement (SLA) in the case that the packet flow is related to some customer connection. We study autonomous packet flow capacity management. We apply RL techniques and propose a management lifecycle consisting of three different phases: 1) a self-tuned threshold-based approach for setting up the connection until enough data is collected, which enables understanding the traffic characteristics; 2) RL operation based on models pre-trained with generic traffic profiles; and 3) RL operation based on models trained with the observed traffic. We show that RL algorithms provide poor performance until they learn optimal policies, as well as when the traffic characteristics change over time. The proposed lifecycle provides remarkable performance from the starting of the connection and it shows the robustness while facing changes in traffic. The contribution is twofold: 1) and on the one hand, we propose a solution based on RL, which shows superior performance with respect to the solution based on prediction; and 2) because vLinks support packet connections, coordination between the intents of both layers is proposed. In this case, the actions taken by the individual PkCs are used by the vLink intent. The results show noticeable performance compared to independent vLink operation.
  • MACIÀ SORROSAL, SANDRA: Towards a domain specific language for computational fluid dynamics in HPC
    Author: MACIÀ SORROSAL, SANDRA
    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: (DAC)
    Mode: Temporary seizure
    Deposit date: 08/04/2022
    Reading date: 26/05/2022
    Reading time: 11:00
    Reading place: FIB - ( https://meet.google.com/tis-ajpk-ogr ) Sala C6-E101 de la FIB
    Thesis director: AYGUADÉ PARRA, EDUARD | BELTRAN QUEROL, VICENÇ
    Committee:
         PRESIDENT: QUINTANA ORTI, ENRIQUE SALVADOR
         SECRETARI: MARTORELL BOFILL, XAVIER
         VOCAL NO PRESENCIAL: BULL, JONATHAN MARK
    Thesis abstract: High-Performance Computing (HPC) evolves vertiginously.Supercomputers are increasingly powerful and complex machines that require deep expertise to be well-exploited.Currently, scientists develop HPC codes using General Purpose Languages (GPLs) and parallel programming models.However, such abstractions are falling short; developing advanced numerical methods and cutting-edge parallelisation strategies requires time, effort and deep computer science expertise, which is unreasonable to expect from other domain scientists.Scientific productivity has become a research challenge.In order to overcome this challenge, computational science demands instruments for practical parallel computations, abstracting scientists from HPC complexities while ensuring the efficient and full exploitation of HPC systems.In this context, Domain-Specific Languages (DSLs) are promising frameworks integrating specific knowledge and capable of automating parts of the code development process.DSLs can become the so-needed productive working environment by decoupling the problem description from the algorithmic implementation.Our task is to push the boundaries of DSLs capabilities and explore their strengths and limitations in HPC environments.We focus on the Computational Fluid Dynamics (CFD) domain to accomplish it.CFD is a field of vast scientific interest and essential for many branches of engineering and industry. Besides its broad applicability, results are obtained from numerical approximations, which can be highly accurate in a reasonable amount of time and investments if CFD codes exploit HPC resources.The object of this thesis is the design and development of Saiph, a DSL for CFD in HPC, exploring the limits of usability, numerical abstraction and automated high-per\-for\-mance.This research provides a high-productivity tool allowing for the direct transcription of CFD problems to generate optimised and mathematically checked code.Saiph provides suitable high-order numerical methods delivering competitive performance and highly accurate and stable results on the numerical side.Moreover, Saiph automatically combines numerical methods, freeing the users from numerical complexities.Finally, the automated use of parallelisation strategies provides high efficient and scalable parallel codes, exploiting current HPC machines at different resource levels.Vectorisation and data-blocking techniques automatically combine with shared and distributed memory parallelisms through fork-join or task-based models and domain decomposition techniques, respectively.We demonstrate the viability and benefits of the DSL, proving it to be a productive and competitive tool for the scientific community.Hence, the DSL philosophy arises as a promising research methodology facing the Exascale era.
  • PEREDO ANDRADE, OSCAR FRANCISCO: Large scale geostatistics with locally varying anisotropy
    Author: PEREDO ANDRADE, OSCAR 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: (DAC)
    Mode: Normal
    Deposit date: 11/04/2022
    Reading date: 09/06/2022
    Reading time: 15:00
    Reading place: FIB- videoconferència ¿ C6-E106 - FIB (meet.google.com/ndo-jdiw-tsd)
    Thesis director: HERRERO ZARAGOZA, JOSE RAMON
    Committee:
         PRESIDENT: QUINTANA ORTI, ENRIQUE SALVADOR
         SECRETARI: AYGUADÉ PARRA, EDUARD
         VOCAL NO PRESENCIAL: ALIAGA ESTELLÉS, JOSE IGNACIO
    Thesis abstract: Classical geostatistical methods are based on the hypothesis of stationarity, which allows to apply repetitive sampling in different locations of the spatial domain, in order to obtain enough information to infer cumulative distributions. In case of non stationarity, anisotropy is observed in the underlying physical phenomena. This feature manifest itself as preferential directions of continuity in the phenomena, i.e. properties are more continuous in one orientation than in another. In the case of local anisotropy, each location of the domain in study presents different preferential directions of continuity. The locally varying anisotropy (LVA) approach in geostatistics allows to incorporate a field of local anisotropy parameters defined for each domain point. With this additional input, more realistic spatial simulations can be generated, including geological features to the computational model such as folds, veins, faults, among others. Since the seminal article published by Boisvert and Deutsch (2011), to the best of the author's knowledge, no further analysis or public code improvements were developed. This is in part because acceleration and parallelization techniques must be applied to the inner kernels of the baseline LVA codes. Large execution time is needed to generate small-scale domain simulations, making large-scale domain simulations a prohibitive task.The contributions of this thesis are accelerating and parallelizing classical and LVA-based geostatistical simulation methods, particularly sequential simulation, which is one of the most common and computationally intensive methods in the field. This fact was recently remarked by some of the main authors in the field, Gómez-Hernández and Srivastava (2021), which shows the relevance of this work today. Two main parallel algorithms and an optimized version of a kd-tree search implementation are presented, all of them applied to both classical and LVA-based sequential simulation implementations. The first parallel algorithm is related to the parallel simulation of different domain points, after rearranging the order of simulation but preserving the exact results of a single-thread execution. The second parallel algorithm is related to the parallel search of neighbour points in the domain, which will be used to build data dependencies for the parallel simulation of points. The optimized kd-tree search was used in each test case in order to reduce the computational complexity of neighbour search tasks. Its modified implementation reduces the number of branching instructions and introduces specialized code sections to accelerate the execution. The main focus is on multi-core architectures using OpenMP and optimization techniques applied to Fortran and C++ codes.Additionally, acceleration and parallelization techniques were also applied to auxiliary applications, such as shortest path and variogram calculation on hybrid CPU/GPU architectures using Fortran, C++ and CUDA codes. In the last application, an analytical and heuristic model was developed to estimate the optimal workload distribution between CPU and GPU in the hybrid context.The overall results of this work are a set of applications that will allow researchers and practitioners to accelerate dramatically the execution of their experiments and simulations, being sgsim, sisim, sgs-lva and sisim-lva the accelerated codes presented. Final speedup results of 11x and 50x are obtained for non-LVA codes using 16 threads, and 56x and 1822x are obtained for LVA codes using 20 threads. These tools can be combined with other geostatistical tools, in order to improve the existing landscape of open source codes that can be used in practical scenarios.
  • TABATABAEIMEHR, FATEMEHSADAT: Distributed collaborative knowledge management for optical network
    Author: TABATABAEIMEHR, FATEMEHSADAT
    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: (DAC)
    Mode: Normal
    Deposit date: 26/04/2022
    Reading date: 02/06/2022
    Reading time: 16:00
    Reading place: FIB- Sala d'actes Martí Recober. Edifici B6 Campus Nord
    Thesis director: VELASCO ESTEBAN, LUIS DOMINGO | COMELLAS COLOME, JAUME
    Committee:
         PRESIDENT: SHARIATI, MOHAMMAD BEHNAM
         SECRETARI: CAREGLIO, DAVIDE
         VOCAL: CASTRO CASALES, ALBERTO ANDRÉS
    Thesis abstract: Network automation has been long time envisioned. In fact, the Telecommunications Management Network (TMN), defined by the International Telecommunication Union (ITU), is a hierarchy of management layers (network element, network, service, and business management), where high-level operational goals propagate from upper to lower layers.The network management architecture has evolved with the development of the Software Defined Networking (SDN) concept that brings programmability to simplify configuration (it breaks down high-level service abstraction into lower-level device abstractions), orchestrates operation, and automatically reacts to changes or events. Besides, the development and deployment of solutions based on Artificial Intelligence (AI) and Machine Learning (ML) for making decisions (control loop) based on the collected monitoring data enables network automation, which targets at reducing operational costs. AI/ML approaches usually require large datasets for training purposes, which are difficult to obtain. The lack of data can be compensated with a collective self-learning approach. In this thesis, we go beyond the aforementioned traditional control loop to achieve an efficient knowledge management (KM) process that enhances network intelligence while bringing down complexity.In this PhD thesis, we propose a general architecture to support KM process based on four main pillars, which enable creating, sharing, assimilating and using knowledge. Next, two alternative strategies based on model inaccuracies and combining model are proposed. To highlight the capacity of KM to adapt to different applications, two use cases are considered to implement KM in a purely centralized and distributed optical network architecture. Along with them, various policies are considered for evaluating KM in data- and model- based strategies. The results target to minimize the amount of data that need to be shared and reduce the convergence error. We apply KM to multilayer networks and propose the PILOT methodology for modeling connectivity services in a sandbox domain. PILOT uses active probes deployed in Central Offices (COs) to obtain real measurements that are used to tune a simulation scenario reproducing the real deployment with high accuracy. A simulator is eventually used to generate large amounts of realistic synthetic data for ML training and validation.We apply KM process also to a more complex network system that consists of several domains, where intra-domain controllers assist a broker plane in estimating accurate inter-domain delay. In addition, the broker identifies and corrects intra-domain model inaccuracies, as well as it computes an accurate compound model. Such models can be used for quality of service (QoS) and accurate end-to-end delay estimations.Finally, we investigate the application on KM in the context of Intent-based Networking (IBN). Knowledge in terms of traffic model and/or traffic perturbation is transferred among agents in a hierarchical architecture. This architecture can support autonomous network operation, like capacity management.It shall be mentioned that part of the work reported in this thesis has been done within the framework of European and National projects. Specifically, the H2020 METRO-HAUL and B5G-OPEN funded by the European Commission, and the MINECO TWINS and AEI IBON, both funded by the Spanish Ministry of Economy, Industry and Competitiveness.

DOCTORAL DEGREE IN ELECTRIC ENERGY SYSTEMS

  • ABDOLLAHI, MOSTAFA: Improving Grid Stability by Integration Renewables using Static Synchronous Generators
    Author: ABDOLLAHI, MOSTAFA
    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 ELECTRIC ENERGY SYSTEMS
    Department: (DEE)
    Mode: Normal
    Deposit date: 27/04/2022
    Reading date: pending
    Reading time: pending
    Reading place: pending
    Thesis director: CANDELA GARCIA, JOSE IGNACIO | ROCABERT DELGADO, JOAN
    Committee:
         PRESIDENT: FERRAMOLA, JUAN MANUEL MAURICIO
         SECRETARI: LUNA ALLOZA, ALVARO
         VOCAL: BOUCHAKOUR, SALIM
    Thesis abstract: The European Commission has plans to transition from classic power system to a net-zero emission power system, mainly by focusing on renewable sources. The power plants owners and power grid operators have technical challenges to achieve this goal.The used renewables technology is one of key challenges. The active power dynamic stability, generation frequency regulation, voltage stability issues, and reactive power balancing are main technical challenges.This Ph.D. thesis proposes a new technology for operation, control, and grid connection of renewable power plant that suports power system dynamic stability during energy transition. The proposed technology is emulation of classic synchronous machine in control loops of electronic power converters, and it provides a feasible operation of a renewable static synchronous generator (SSG) based on synchronous power controller (SPC).The proposed technology (RSSG-SPC) has flexibility and can comply with grid codes. The SPC technique is the core of RSSGSPC technology. So, there are two main parts in RSSG-SPC. The electromechanical part emulates performance of synchronous power generation. This part provides virtual damping and virtual inertia functionalities and it contributes to active power control and frequency regulation. The second part is virtual admittance which provides the control of a voltage source converter in current mode.So, the converter can be modeled such as Thevenin model of synchronous generator. This part provides reactive power control and voltage regulation. The theory of RSSG-SPC, control layers modeling, and RSSG SPC¿s grid connection modeling are illustrated. The RSSG-SPC¿s operations to overcome technical challenges during grid connection, RSSG-SPC¿s flexibilities to comply with grid codes, and RSSG-SPC¿s capabilities to support dynamic stability have been discussed.The performance of renewable power plant based on RSSG-SPC technology has been evaluated by doing detailed mathematical analysis, dynamic modeling, time domain simulation, and laboratory tests validations. The RSSG-SPC grid connection is analyzed for several network topologies and different RSSG-SPC operations including, i) RSSG-SPC connected to simple bus supported by weak grid either while bus is supported by a stiff grid, ii) RSSG-SPC operates to support a long ac transmission system, iii) RSSGSPC contributes in a unique generation area system (IEEE 14B), iv) RSSG-SPC operates as big generation plant and supports a multi area generation system (Kundur¿s system), and v) RSSG-SPC operates as a small generation unit in Kundur¿s system.An algorithm is developed for implementation and modeling of RSSG-SPC in the noted applications. The algorithm covers RSSGSPC grid connection modeling taking to account the parameters of RSSG-SPC and power grid. The dynamic indices are proposed for tuning of RSSG-SPC¿s dynamic parameters (virtual inertia and virtual damping) aiming to have a stable operation of RSSG-SPC.Also, considering the real situation of power grid, adequate modifications are applied to RSSG-SPC¿s control layers leads to provide adaptable operation of RSSG-SPC in the grid connection mode. Moreover, an active power limiter is proposed to solve the power transfer limitation of renewables and to provide functionalities to follow the grid operators balancing signals.

DOCTORAL DEGREE IN ELECTRICAL ENGINEERING

  • SAURA PERISE, JAIME: Contribucions a l'estudi de rectificadors no controlats m-fàsics en condicions no equilibrades per unitats TRUs o ATRUs multi polsos
    Author: SAURA PERISE, 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: (DEE)
    Mode: Normal
    Deposit date: 06/05/2022
    Reading date: pending
    Reading time: pending
    Reading place: pending
    Thesis director: BOGARRA RODRIGUEZ, SANTIAGO
    Committee:
         PRESIDENT: GUASCH PESQUER, LUIS
         SECRETARI: MONJO MUR, LLUÍS
         VOCAL: HERRAIZ JARAMILLO, SERGIO
    Thesis abstract: This doctoral thesis has been developed to provide a new point of view and a new approach to the analysis and study of uncontrolled bridge rectifiers. The methodology developed has been generalized to extend the study to an m-phase system, applicable for both balanced and unbalanced systems.It is possible to quickly obtain an analytical formulation to calculate the average voltage for balanced systems. However, there are multiple formulations for unbalanced systems, and, in general, it is not easy to be applied. For this reason, an easy-to-apply formulation has been determined to calculate the average voltage, using the perimeter of the convex polygon defined by the ends of the phase voltages of the power supplies. As the convexity condition is necessary for its application, it has been determined that this approach is related to one of the formulas proposed by Cauchy. This formula determines the average width of a convex body, which has made it possible to relate the average width to the average voltage and the convex body to the convex polygon defined by the maximum stresses.The relationship with vision systems also has been observed. The projections and average widths in a rotation are used, for example, to determine the section of bones, veins, and muscles, which is the basis of the Computed Tomography (CT) scan. It is important to highlight the close relationship between the Couchy formula and the application to the CT scan.However, the proposed method has some differences from Cauchy's. While the Cauchy formulation applies to a body that must be derivable at all points, the proposed formulation applies to a convex polygon with no equal derivative at the vertices since the derivatives are different from the right than from the left vertex. This new method, called the Phasorial Convex Hull Method, has been published in the article "Average value of DC-link output voltage in multi-phase uncontrolled bridge rectifiers under supply voltage balance and unbalance conditions".In the demonstration of the developed method, it has been observed that the instantaneous voltage is obtained before calculating the average voltage of the DC bus. Therefore, the voltage signature at the rectifier's output allows detailed studies of behavior in the voltage sag, unbalance operation, faults, etc. This new methodology for obtaining instantaneous voltage has been titled "Shadow Projection", presented in the article "New Methodology to Calculate DC Voltage Signature in N-Phases TRUs Under Supply Voltage Sags". Because rectifiers are usually coupled to Transformers or Autotransformers, the Thesis was believed to be linked to Transformer Rectifier Units (TRUs) and Auto-Transformer Rectifier Units (ATRUs) and a patent study has been done to see how the industry has evolved, studying some configurations. Formulations have been proposed for solutions for series, parallel and / or coupling connections.The joint study of the rectifying units with the Transformer or the Autotransformer opens the study to determine the line currents on the AC side. Therefore, if the study of voltages goes from AC sources to DC load, the study of currents goes from DC side to AC side. Solutions have been proposed for the study of 12-pulse rectifiers in three-winding TRUs, and for Delta-polygonal ATRUs. This study, yet to be published, allows obtaining simple equivalent circuits for complex systems.The effect on DC voltage when there are fused diodes producing a lack of open circuit has also been studied, the proposed method allows to determine the diode or diodes that are missing and need to be replaced. In this case, the article entitled ¿Open-Circuit fault diagnosis and maintenance in multi-pulse parallel and series TRU topologies¿ has been published. The method is based on signing the DC voltage at the output of the rectifier, starting the period according to the hourly index of the transformer for 12-18 pulses.

DOCTORAL DEGREE IN ELECTRONIC ENGINEERING

  • ALFARO ARAGÓN, CARLOS ARTURO: Una nueva perspectiva del modelado y control de microrredes eléctricas y convertidores de potencia
    Author: ALFARO ARAGÓN, CARLOS ARTURO
    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 ELECTRONIC ENGINEERING
    Department: Department of Electronic Engineering (EEL)
    Mode: Article-based thesis
    Deposit date: 02/05/2022
    Reading date: pending
    Reading time: pending
    Reading place: pending
    Thesis director: GARCIA DE VICUÑA MUÑOZ DE LA NAVA, JOSE LUIS | GUZMAN SOLA, RAMON
    Committee:
         PRESIDENT: FIGUERES AMORÓS, EMILIO
         SECRETARI: CASTILLA FERNANDEZ, MIGUEL
         VOCAL: GARCERÁ SANFELIU, GABRIEL
    Thesis abstract: This doctoral thesis focuses on the modeling and control of electrical microgrids and triphasic converters. The starting points of this research work are based on previous work on modeling electrical microgrids working in isolated mode, and on the theoretical basis of control based on the slope method, widely studied in electrical microgrids. In addition, this work is basedon previous work on predictive control applied to three-phase converters, and on the theoretical bases of this type of control widely used in Power Electronics. The main contribution of this doctoral thesis is the deduction of a large-signal mathematicalmodel that describes the dynamics of the active and reactive powers that flow through converters connected in the microgrid.This proposal will make it possible to obtain new control techniques for three-phase converters connected in microgrids, suchas model-based predictive control, for example. It should be noted that the use of this model can be used as a tool to deducethe global stability of the microgrid. The systems treated in this thesis are a three-phase rectifier with a unity power factor anda three-phase microgrid composed of five three-phase inverters.
  • CANZIANI AMICO, FRANCO: Design and Implementation of Rural Microgrids ¿ Laguna Grande Case Study
    Author: CANZIANI AMICO, FRANCO
    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 ELECTRONIC ENGINEERING
    Department: Department of Electronic Engineering (EEL)
    Mode: Normal
    Deposit date: 31/03/2022
    Reading date: 22/07/2022
    Reading time: 11:00
    Reading place: EPSEVG - Aula màster
    Thesis director: CASTILLA FERNANDEZ, MIGUEL | MIRET TOMAS, JAUME
    Committee:
         PRESIDENT: FIGUERES AMORÓS, EMILIO
         SECRETARI: GARCIA DE VICUÑA MUÑOZ DE LA NAVA, JOSE LUIS
         VOCAL: GARCERÁ SANFELIU, GABRIEL
    Thesis abstract: In 2015 the United Nations established the 17 Sustainable Development Goals: a set of interrelated objectives and a guide to reach a more sustainable and higher quality future for all humanity.The goals were set with a timeline for 2030, the seventh goal refers specifically to the universal access to ¿affordable and clean energy¿. Taking account the considerable fraction of world population that do not have access to electricity, especially in rural areas, this goal still requires a great effort and investment.Rural hybrid microgrids, that integrate and manage solar and wind energy resources to provide electricservice to remote locations, are a promising solution to reach this ¿last mile¿ scenario. However, as is reported in the literature, there is still scarce information about the performance of these systems based on measured data obtained in real working field conditions. This work aims to contribute to this aspect mainly by analyzing the data obtained in the 9 kW Laguna Grande community hybrid microgrid, which is cooperative since 2016 in the coast of Perú, and has been equipped with sensors and data acquisitionsystems that measure and register solar radiation, wind speed, temperatures, and all the relevant electric parameters.As a preliminary study, the rural electrification gap and costs are assessed, as well as the availability of solar and wind resources in the area of interest. A literature and state of the art review is undertaken followed by the definition of the microgrid concept and the different ways in which a rural microgrid can be configured. The particular way in which the Laguna Grande microgrid is configured and instrumented is described. Measured meteorological conditions as solar radiation, wind speed and temperature are analyzed and related to the power generated by the photovoltaic arrays and wind turbine. This in turn leads to a balance with respect to the power delivered to the community and consequently to the voltage levels of the battery bank. Battery dynamics concepts are used to determine the depth of discharge (DOD) of the batteries in a real time regime. The statistics of the DOD values allows for the duration of the battery to be estimated which is a key factor to the microgrid economics and reliability.A parametric study is done to assess the effect of varying battery size on the technical andeconomic performance of the microgrid; similarly, with generating capacity in both photovoltaic arraysand wind turbines. Complementarily, a commercial software is used to optimize the microgrid, introducing state of the art components as lithium-ion batteries, power electronics and photovoltaic modules for a future upgrade. Finally, this study would not be complete without emphasizing the importance and adequate consideration of the human factor for the success and long-term sustainability of rural electrification projects.
  • CISNEROS FERNÁNDEZ, JOSE AGUSTÍN: Low-Power High-Channel-Count CMOS ROICs for Multiplexed Arrays of Graphene Transistors in Large-Area µECoG
    Author: CISNEROS FERNÁNDEZ, JOSE AGUSTÍN
    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 ELECTRONIC ENGINEERING
    Department: Department of Electronic Engineering (EEL)
    Mode: Normal
    Deposit date: 27/04/2022
    Reading date: pending
    Reading time: pending
    Reading place: pending
    Thesis director: SERRA GRAELLS, FRANCESC | GUIMERA BRUNET, ANTON
    Committee:
         PRESIDENT: DELGADO RESTITUTO, MANUEL
         SECRETARI: MOLL ECHETO, FRANCESC DE BORJA
         VOCAL: MORA LOPEZ, CAROLINA
    Thesis abstract: There is an increasing interest on the development of neural interfaces able to decipher the neural activity across multiple regions of the brain. The ultimate goal is understanding how the underlying brain dynamics drive the cognitive activities, such learning and moving or the response towards impairing diseases. Despite the huge advance in neuroscience, there is still a lack of knowledge for a complete conception of the brain, mainly because the neural activity spans over a wide range of temporal and spatial resolutions making it difficult to be recorded with a single technology.The electrical nature of the brain activity makes electrophysiology of paramount importance for the deep study of brain dynamics. Indeed, the current state-of-art invasive electrophysiological techniques include intracortical monolithic CMOS ROICs able to resolve the neural activity from single neurons, and epicortical hybrid MEAs for the recording of µECoG signals. The monolithic solutions have benefited from the scalability of CMOS technologies, with on-chip recording sensors and circuits, while hybrid neural interfaces still suffer from the point-to-point connectivity limitations and they have been mainly focused on exotic materials and discrete electronics.This PhD thesis explores novel multiplexing techniques for graphene active sensing arrays by means of tailored ROIC architectures and mixed-signal CMOS circuits, which extend the state-of-art coverage to larger areas with high-density neural interfaces by solving the current connectivity restrictions of hybrid systems. In this sense, this research presents two 1024-channel ROIC demonstrators in 1.8-V 180-nm CMOS technology representing a substantial increment on the channel count in hybrid systems while keeping the system integration at low cost and low complexity.The first research line, proposes a conservative approach based on a time-domain multiplexing scheme to minimize the connectivity for G-SGFET-only sensor arrays by moving the selection switches to the CMOS ROIC. Apart from solving the connectivity issue, the proposed multiplexing scheme is able to reduce the array technological complexity while preserving the demonstrated DC-coupled neural recording capability of G-SGFET sensors. Moreover, a modular ROIC architecture and accompanying CMOS circuits are introduced to overcome the main design challenges on channel-count scalability, like individual offset current cancellation or the degradation of the AFE noise figures. In addition, electrical tests together with in-vivo experimental results are presented to support the system capabilities of this first complete state-of-art hybrid ROIC specially designed for G-SGFET sensors.The second research line proposes a novel frequency-domain multiplexing technique capable of exploiting the intrinsic mixer capabilities of the graphene transistor to achieve a truly switch-less operation of high-channel-count G-SGFET-only probes. The mixing process allocates in continuous time the desired neural signal from the gate of the sensor into a desired frequency band avoiding both CMOS flicker noise and sampled noise folding. Scalability in this state-of-art advancement is reached by means of a custom modular ROIC architecture and specific CMOS circuit blocks. Indeed, the solutions are presented for the main design challenges in terms of generation of the required harmonic carriers and optimization of the shared full scale occupancy. The resulting neural interface is still DC coupled and capable of infra-slow recording. Finally, electrical test and in-vivo experiments are reported to support the working hypothesis.
  • LUO, CHENGYANG: Textile UHF-RFID Antenna Sensors Based on Material Features, Interfaces and Application Scenarios
    Author: LUO, CHENGYANG
    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 ELECTRONIC ENGINEERING
    Department: Department of Electronic Engineering (EEL)
    Mode: Article-based thesis
    Deposit date: 28/04/2022
    Reading date: 21/06/2022
    Reading time: 11:00
    Reading place: ETSEIAAT - sala de conferencias TR1, ESEIAAT, Campus Terrassa.
    Thesis director: FERNANDEZ GARCIA, RAUL | GIL GALI, IGNACIO
    Committee:
         PRESIDENT: BONACHE ALBACETE, JORDI
         SECRETARI: AMANTE GARCIA, BEATRIZ
         VOCAL: SIEIRO CÓRDOBA, JAVIER JOSÉ
    Thesis abstract: Radio frequency identification over measurable ultra-high frequency textile substrates (UHF-RFID) is a promising technology to develop new applications in the field of health and the Internet of Things (IOT), due to the massive use of fabrics and the technological maturity of embroidery techniques. This thesis is the result of a compendium of publications on this topic. First, as a result of the analysis of the state of art, a systematic review entitled 'Wearable textile UHF-RFID sensors: A systematic review' has been published.The thesis aims to improve research on UHF-RFID textile-based sensor technology. Thanks to the analysis of the state of art, three novel research objectives have been set that are worth exploring. The first is to study novel detection functions for textile UHF-RFID based sensor technology; the second is to find a connection/interface solution between textile antennas and integrated circuit (IC) chips and the third is to reduce the costs of such technology to promote future commercial applications. To contextualize the thesis, it includes the necessary theoretical fundamentals and the manufacturing and characterization methods used during it.As a result of the work derived from the first objective, a scientific article entitled ¿Textile UHF-RFID Antenna Sensor for Measurements of Sucrose Solutions in Different Levels of Concentration¿ has been published. In this work, a textile UHF-RFID tag with two detection positions is proposed for sucrose solution measurements. The two detection positions with the different detection functions show good performance and can offer two options for future full applications. In addition, another scientific article entitled ¿ Textile UHF-RFID Antenna Embroidered on Surgical Masks for Future Textile Sensing Applications¿ has been published to support the first objective. The inspiration for this work came from the current pandemic situation. This work develops three progressive designs of textile UHF-RFID antennas over surgical masks due to the current global epidemic situation. Reliability testing demonstrated that the proposed designs can be used for human healthcare focused applications.As a result of the second objective, a research article entitled 'Experimental Comparison of Three Electro-textile Interfaces for Textile UHF-RFID Tags on Clothes' has been published. This work proposes three electro-textile interfaces integrated with the corresponding textile UHF-RFID antennas and provides the chip-textile connection solutions (through sewing, push buttons and insertion). As a result of this objective, an electro-textile interconnect system has been proposed together with its electrical model, which allows the correct adaptation of impedances between the RFID antennas and the integrated circuit. It is worth noting that the mixed-use feasibility of the proposed electro-textile interfaces and the designed textile UHF-RFID antennas has been verified, reducing the cost in the design procedure in applications where the read range requirements of the order of 1 meter.The third objective has been achieved and exposed by a scientific article entitled 'Electro-textile UHF-RFID Compression Sensor for Health-caring Applications'. It proposes a single UHF-RFID based compression textile sensor that can be used simultaneously in two different healthcare application scenarios, which directly impacts on cost reduction.
  • RILLO MORAL, FRANCESC IU: New Autonomous sensor system for the continous monitoring of the composting process from the inside
    Author: RILLO MORAL, FRANCESC IU
    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 ELECTRONIC ENGINEERING
    Department: Department of Electronic Engineering (EEL)
    Mode: Normal
    Deposit date: 11/01/2016
    Reading date: pending
    Reading time: pending
    Reading place: pending
    Thesis director: CASAS PIEDRAFITA, JAIME OSCAR
    Committee:
         PRESIDENT: BRETTERKLIEBER, THOMAS
         SECRETARI: QUILEZ FIGUEROLA, MARCOS
         VOCAL: CASAS NEBRA, ROBERTO JOSE
    Thesis abstract: The composting process is Nature¿s way of recycling organic wastes with a good quality organic fertilizer as a result. This process, though, needs of a thoroughly monitoring of temperature and humidity for a good resulting material. During this Ph.D thesis we developed a wireless temperature and humidity autonomous system that monitored from the inside of compost. The fact of measuring and transmitting from the inside implies the need of a protection for the circuit and an issue in the measure.Temperature suffers delays when measuring from the inside of a protection and, as such, we developed an algorithm, implementable on microcontrollers, to counteract the effects of first order step responses. The conditioning has been optimized in terms of components and consumption, obtaining a theoretical and experimental comparative between the classic conditioning and the use of direct interfaces.Commercial humidity sensors need to be in direct contact with the environment they are measuring, but that is not possible in compost since they can get damaged. That is why we designed a humidity sensor based on coplanar capacitive electrodes that can measure through a protection layer. Some theoretical models have been obtained for the physical optimization of both the sensor and the influence of the protective layer.Compost has never been characterised as a transmission environment, and as such, communications in compost are innovative. The heterogeneity of the material and its changes in humidity, temperature and density made the transmission complex. We found the proper frequency band to commercially work in compost and the RF transmission model in compost to estimate attenuation vs distance.

DOCTORAL DEGREE IN ENVIRONMENTAL ENGINEERING

  • GASPARINI, ANDREA: Experimental and numerical modelling of CO2 behaviour in the soil-atmosphere interface. lmplications far risk assessment of carbon capture storage projects.
    Author: GASPARINI, 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 ENVIRONMENTAL ENGINEERING
    Department: (DECA)
    Mode: Article-based thesis
    Deposit date: 07/02/2020
    Reading date: pending
    Reading time: pending
    Reading place: pending
    Thesis director: GRANDIA I BORRÀS, FIDEL | BRUNO I SALGOT, JORGE
    Committee:
         PRESIDENT: VOLTATTORNI, NUNZIA
         SECRETARI: FOLCH DURAN, ARNAU
         VOCAL: MAZADIEGO MARTINEZ, LUIS FELIPE
    Thesis abstract: CO2 geological storage is considered one of the options technologically viable in order to decrease the industrial emissions of this gas species that strongly contribute to the greenhouse effect in the atmosphere (IPCC, 2005). As naturally, oil and gas are stored in porous rocks that have the same key geological features required for CO2 storage, so CCS aim to recreate a natural process to trap carbon dioxide for millions of years into deep saline aquifer or depleted oil and gas fields. Episodic release of CO2 from underground can occur from either natural processes (i.e., mantle degassing, thermal decarbonation, volcanic areas) or industrial (geological storage of CO2, CCS). Because of leakage can occur at every step of a CCS project, monitoring assumes an important role not only during and after injection but also before in order to know the state of the entire site from deep underground (reservoir level) to surface. In this respect, the use of atmospheric dispersion numerical models helps predicting the dispersion of the CO2-enriched gas plume once emitted from underground and allows an accurate map of risk level through time under particular meteorological conditions. The aim of this PhD. project is to give a better understanding of CO2 behaviour in the unsaturated zone and its atmospheric dispersion. The results are obtained from experimental and numerical modelling of CO2 leakage from an artificial leakage site and from natural analogues applied to risk assessment for CCS sites. To reach the above-mentioned targets and to prove results, this research plan combines experimental activity on site and numerical modelling. The first part of the research plan consisted of a contribution in the PISCO2 project at the ES.CO2 facilities placed in Ponferrada (Spain). The objective of this project was to predict how the injected CO2 will move laterally and vertically in the unsaturated zone and to determine the critical parameters that will affect the ecosystems. This part has been published in a peer review journal and presented in an international congress.The second part of the PhD. project has focused on the study of two natural analogues in volcanic areas. Natural analogues provide evidences of the impact of CO2 leakage, for both sites two approaches have been followed: a) direct measurement of air concentration and b) numerical atmospheric modelling with the TWODEE2 code. The study of CO2 emissions in natural systems provides a valuable information on the assessment and quantification of potential risks related to underground carbon storage leakage. Emissions of CO2 are studied in a large variety of geological environments, i.e., sedimentary basins, active andnon-active volcanic areas, seismically-active regions, and geothermal fields. Because of the physics of carbon dioxide gas, e.g., colourless, odourless, higher density compared to air, its accumulation may result hazardous and even lethal for life. The objective of atmospheric dispersion modelling is to predict how will move the plume, generated by a leakage in natural degassing systems and CCS sites.Results obtained from this doctorate provide:¿Coupling experimental and numerical data in order to test new methods and/or numerical codes;¿New elements to the knowledge of CO2 behaviours in the unsaturated zone as seen at PISCO2;¿New clues on non-invasive monitoring techniques for CCS sites and natural analogues;¿The usefulness of studying natural analogues;¿The usefulness of the SAP system, as a good method to evaluate high gas emissions from underground;¿The efficiency of atmospheric modelling as a valuable methodology in the risk assessment;¿The importance of risk assessment maps in active degassing areas;¿The need of production of forecasting maps to evaluate dangerous scenarios.¿Numerical models (multiphase transport and atmospheric gas dispersion) are proved to be useful tools to predict gas behaviour inthe vadose zone and in the near-grou

DOCTORAL DEGREE IN GEOTECHNICAL ENGINEERING

  • BARRA, ANNA: Advanced exploitation of Sentinel-1 data for supporting landslide risk analysis
    Author: BARRA, ANNA
    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: (DECA)
    Mode: Article-based thesis
    Deposit date: 06/04/2022
    Reading date: 31/05/2022
    Reading time: 12:00
    Reading place: ETSECCPB- Auditorium (Sala d'Actes), Edificio B6, CTTC, Avinguda Carl Friedrich Gauss 11, 08860, Castelldefels, Barcelona
    Thesis director: MONSERRAT HERNANDEZ, ORIOL | HERRERA GARCIA, GERARDO
    Committee:
         PRESIDENT: ZEZERE, JOSÉ LUÍS
         SECRETARI: GUINAU SELLES, MARTA
         VOCAL: ZUCCA, FRANCESCO
    Thesis abstract: Satellite Synthetic Aperture Radar Interferometry (InSAR) and Persistent Scatterer Interferometry (PSI) are now consolidated tools for ground movement detection and monitoring. Sentinel-1 (S1) is the first satellite providing free data access and ensuring a regular acquisition worldwide, every 6 days, increasing its potential for long-term monitoring applications. Several regional and national ground motion services are already active, providing products based on S1 data. Soon in 2022 the first European Ground Motion Service (EGMS) will be available and freely provide a displacement map over the whole Europe, with annual updates. This implies a strong expansion of availability of PSI-based displacement maps and an easy access for anyone, with an increasing interest among a wider range of users, including public or governmental institutions, academia, industry, and citizens. The analysis and interpretation of this amount of data is difficult and time consuming, mostly for non-expert InSAR users. The objective of this work is developing methodologies to simplify the operational use of PSI displacement maps, generating derived products with a clear message, easy-to-interpret, and fast to read. We propose a method to be applied over regional scale PSI displacement maps, to fast detect the most significant Active Deformation Areas (ADAs). The ADA map is a first product that allows a fast focusing on the active areas, to prioritize further analysis and investigation. Starting from the ADAs, the potential phenomena are attributed to each area through a preliminary interpretation based on auxiliary data, to derive the Geohazard Activity Map. In this work, a methodology to include the ADA information in the Civil Protection Activities is proposed, with the main output called Vulnerable Elements Activity Maps (VEAM). An application of the VEAM is illustrated in the Canary Islands. Furthermore, the ADA map is used in the Valle d'Aosta Region (Northern of Italy) to generate vulnerability and potential loss maps. Finally, a methodology to derive potential damage maps of the exposed buildings, based on the spatial gradients of movement, is proposed, and applied in a coastal area of the Province of Granada (Spain). A pack of software tools has been developed based on the proposed methods to extract ADA and then classify them to generate a Geohazard Activity Map. The set of tools is called ADATools, it is open-access, easy to use and fast, improving the operational exploitation of PSI regional-scale displacement maps. All the methodologies have been developed in the frame of several European projects (Safety, U-Geohaz, MOMIT and RISKCOAST), and are aimed at supporting the multi-scale territorial management and risk analysis activities, with a specific focus on landslides.
  • COLLICO, STEFANO: Optimazation of marine sediments characterization via statistical analysis
    Author: COLLICO, STEFANO
    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: (DECA)
    Mode: Normal
    Deposit date: 09/04/2022
    Reading date: 13/06/2022
    Reading time: 12:00
    Reading place: ETSECCPB.Building C1. Classroom: 002 C/Jordi Girona, 1-3 08034 Barcelona
    Thesis director: ARROYO ALVAREZ DE TOLEDO, MARCOS
    Committee:
         PRESIDENT: JIMENEZ RODRIGUEZ, RAFAEL
         SECRETARI: LEDESMA VILLALBA, ALBERTO
         VOCAL NO PRESENCIAL: URGELES ESCLASANS, ROGER
    Thesis abstract: The task of geotechnical site characterization includes defining the layout of ground units and establishing their relevant engineering properties. This is an activity in which uncertainties of different nature (inherent, experimental, of interpretation¿) are always present and in which the amount and characteristics of available data are highly variable. Probabilistic methodologies are applied to assess and manage uncertainties. A Bayesian perspective of probability, that roots probability on belief, is well suited for geotechnical characterization problems, as it has flexibility to handle different kind of uncertainties and highly variable datasets ¿in quality and quantity. This thesis addresses different topics of geotechnical site characterization from a probabilistic perspective, with emphasis on offshore investigation, on the Cone Penetration Test (CPTu) and on Bayesian methodologies.The first topicaddresses soil layer delineation based on CPT(u) data. The starting point is the recognition that layer delineation is problem-oriented and has a strong subjective component. We propose a novel CPTu record analysis methodology which aims to: a) elicit the heuristics that intervene in layer delineation, facilitating communication and coherence in interpretation b) facilitate probabilisticcharacterization of the identified layers c) is simple and intuitive to use. The method is based on sequential distribution fitting in conventionally accepted classification spaces (Soil Behavior Type charts). The proposed technique is applied at different sites, illustrating how it can be related to borehole observations, how it compares with alternative methodologies and how it can beextended to create cross-site profiles. The second topic addresses strain-rate corrections of dynamic CPTu data. Dynamic CPTu impact on the seafloor and are very agile characterization tools. However, they require transformation to equivalent quasi-static results that can be conventionally interpreted. Up to now the necessary corrections are either too vague or require the acquisition of paired dynamic and quasi-static CPTu records (i.e., same location¿s acquisition). A Bayesian methodology is applied to derive strain-rate coefficients in a more general setting, one in which some quasi-static CPTu records are available in the study area, but they need not be paired to any converted dynamic CPTu. Application to a case study offshore Nice shows that the results match those obtained using paired tests. Furthermore, strain rate correction coefficients and transformed quasi-static profiles are expressed in probabilistic terms.The thirdtopic addressed is the optimization of soil unit weight prediction from CPTu readings. A Bayesian Mixture Analysis is applied to a global database to identify hidden soil classes within it. The goal is to improve the accuracy of regressions between geotechnical parameters obtained by exploiting the database. The method is applied to predict soil unit weight from CPTu data, a problem that has intrinsic practical interest but it is also representative of difficulties faced by a larger class of problems in geotechnical regression. Results highlight a decrease of systematic transformation uncertainty and an improve of accuracy of soil unit weight prediction from CPTu at new sites. In a final application we present a probabilistic earthquake-induced landslide susceptibility map of the South-West Iberian margin. A simplified geotechnical pixel-based slope stability model is considered to whole study area within which the key stability model parameters are treated as random variables. Site characterization at the regional scalecombines a global database with available geotechnical data through a Bayesian scheme. Outputs (landslide susceptibility maps)are derived from a reliability-based design procedure (Montecarlo simulations) providing a robust landslide susceptibility prediction at the site according to Receiver Operating Curve

DOCTORAL DEGREE IN MARINE SCIENCES

  • QUIRÓS COLLAZOS, LUCÍA: Estudio paleoclimático del afloramiento ecuatorial del Océano Pacífico durante los últimos 160.000 años a partir de biomarcadores moleculares.
    Author: QUIRÓS COLLAZOS, LUCÍA
    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 MARINE SCIENCES
    Department: (DECA)
    Mode: Normal
    Deposit date: 22/04/2022
    Reading date: 27/06/2022
    Reading time: 10:00
    Reading place: ETSECCPB - Saló d'Actes Ramon Margalef de l'Institut de Ciències del Mar del CSIC.
    Thesis director: CALVO COSTA, EVA | PELEJERO I BOU, CARLES
    Committee:
         PRESIDENT: FLORES VILLAREJO, JOSE-ABEL
         SECRETARI: CERMEÑO AÍNSA, PEDRO
         VOCAL: VILLANUEVA ALVAREZ, LAURA
    Thesis abstract: The present PhD thesis is focused on the paleoclimatic reconstruction of the Pacific Ocean equatorial upwelling conditions, east of the Galapagos Islands, over the last 160.000 years. This region is of great interest to understand climate dynamics within the context of current global change, as it plays a key role in global biogeochemical cycles, especially the carbon cycle, being one of the areas with largest CO2 fluxes from the ocean to the atmosphere. In addition, studies covering the recent decades have shown that tropical regions play a key role in regulating global climate, since they control the transfer of thermal energy from low to high latitudes.This study is based on the analysis of molecular biomarkers in the marine sediment core ODP 1240, which was obtained during Leg 202 of the Ocean Drilling Program. The main analysed compounds were the long-chain ketones, known as C37 alkenones, the 24-methylcholesta-5,22-dien-3ß-ol, known as brassicasterol, long-chain n-alkanes, glycerol dialkyl glycerol tetraethers (GDGTs) and 1,14-alkyl diols.The UK'37 and TEXH86 indexes were obtained from the analyses of the mentioned biomarkers to assess their suitability as temperature proxies to reconstruct sea surface conditions at the eastern Pacific upwelling on a glacial-interglacial time scale. They reflect variations in the mean annual surface temperature at the study area and track the warming and cooling trends typical of glacial-interglacial variations, although with certain peculiarities associated with each proxy. The UK'37 derived record shows a special sensitivity to periods with La Niña-like seasonal conditions, when the upwelling was more intense and sea surface temperatures in this area were colder. On the other hand, the TEXH86 index shows a tendency to overestimate the cooling of surface waters during glacial periods, as it has been also observed in similar reconstructions in this and other tropical regions. This might be due to the combined influence of changes in surface temperature and in ammonium oxidation rates of the Thaumarchaeotas that synthesize GDGTs and proliferate in the upper water column.Paleoclimatic information provided by other records nearby indicate that changes in oceanic denitrification linked to the supply of oxygen through subsurface and intermediate waters could have a regulating effect on the availability of ammonium in surface water. This, in turn, would have led to changes in the relative abundance of the GDGTs synthesized by Thaumarchaeotas, causing a glacial cooling overestimation through the TEXH86 index.The high resolution that characterizes the ODP 1240 core has allowed gaining a more in-depth knowledge on the millennial-scale climatic variability of this region. In particular, the changes in primary production during the penultimate deglaciation have been studied. This deglaciation, known as Termination II, can be used as a laboratory to understand climate dynamics during periods of rapid global warming. The results show that phytoplankton production was enhanced by an increasing influence of nutrient-rich Southern Ocean-sourced waters and by enhanced atmospheric dust inputs, which would have served as an additional source of iron to the study region. These processes culminated during the development of the Heinrich Event 11 in the North Atlantic, at a time when the highest increase in primary productivity of Termination II was recorded in the eastern equatorial Pacific upwelling. The results of this thesis highlight the relationships between global dynamics of biogeochemical cycles and those of the eastern equatorial Pacific, as well as the role played by high to low latitude teleconnections.

DOCTORAL DEGREE IN NATURAL RESOURCES AND THE ENVIRONMENT

  • HERMS CANELLAS, JOAN IGNASI: Contribution to the hydrogeological knowledge of the high mountain karst aquifer of the Port del Comte (SE, Pyrenees)
    Author: HERMS CANELLAS, JOAN IGNASI
    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 NATURAL RESOURCES AND THE ENVIRONMENT
    Department: Department of Mining, Industrial and ICT Engineering (EMIT)
    Mode: Article-based thesis
    Deposit date: 04/04/2022
    Reading date: 02/06/2022
    Reading time: 16:30
    Reading place: Sala d'actes Escola Politècnica Superior d'Enginyeria de Manresa - Av. Bases de Manresa,61-73 - 08242 Manresa
    Thesis director: SOLER GIL, ALBERT | JORGE SANCHEZ, JUAN
    Committee:
         PRESIDENT: MAS PLA, JOSEP
         SECRETARI: FOLCH SANCHO, ALBERT
         VOCAL NO PRESENCIAL: DANIELE, DOLORINDA
    Thesis abstract: This thesis has aimed to improve the hydrogeological knowledge of the Port del Comte Massif (PCM), a karstic aquifer system located in the south-eastern sector of the Pyrenees that plays a strategic role in the provision of water resources in the basins of the Llobregat and Segre river basins. The specific objectives have been aimed at deepening the knowledge of the geological structure of its reservoirs, the hydrodynamic and geochemical behaviour, the establishment of a conceptual model; and the study of climate change (CC) scenarios. A data acquisition work has been carried out followed by its processing and modeling. The results have been published in 4 peer-reviewed scientific papers. The work has been complemented by participation in the EU GeoERA RESOURCE project, where through this thesis, the PCM has been one of the case studies, contributing to the development and testing of new methods for classifying karstic aquifers.The main aquifer is located in the lower Eocene limestones and dolomites. This aquifer presents in the highest parts of the massif an important karstic development. The overlying materials from the Upper Eocene-Oligocene and the underlying Cretaceous and Triassic constitute relevant aquifers for local supply. More than 100 springs have been inventoried in the study area, of which 43 were selected for monitoring tasks. Of the total, 4 correspond to the main discharge points of the system: the ¿Cardener¿ spring that discharges to the East into the Cardener River, ¿Sant Quintí¿ that discharges to the SE in the Fred River basin; ¿Aiguaneix¿ that discharges towards the NW in the Alinyà River; and ¿Can Sala¿ that discharges towards the SE. In addition, there is also a diffuse groundwater flow in a northerly direction towards the La Vansa river basin, and discharge through multiple local springs spread throughout the massif. The use of hydrological models has made it possible to estimate the recharge time-series and the mean transit times in the main karst springs. The recession analysis focused on the "Cardener" spring suggests that it is in the domain of "complex karst systems" similar to the behaviour of other karst springs in the Pyrenees. The new evaluation systems KGWRAI-V and RC-V show that the "Cardener and Sant Quintí" springs can be classified with "medium to high vulnerability" and with "moderate regulatory capacity¿. Among the various results obtained from the simulations of the climate change emission scenarios RCP 4.5 and 8.5 for the "Cardener" spring, on average it is observed that the temperature in a horizon of 35 years could increase by about 1.3 ºC and the snow cover could be reduced by 50%. From the geochemical point of view, the underground water is predominantly of the calcium-bicarbonate type, although up to 6 different facies types have been identified. The multivariate statistical approach using a clustering method based on Gaussian mixture models allowed to classify the 43 springs into 4 groups. These new associations made it possible to better determine natural background levels at aquifer scale for sulfate, nitrate, and chloride. Several points present sulfate concentrations above the potability limit, being the main source of geogenic origin. The nitrate concentration is generally low except in specific points related to agricultural and livestock practices. The results obtained have meant an important advance in the knowledge of the karstic aquifer system of the MPC. The methodology could be replicated in the rest of the strategic karstic aquifers of the Pyrenees, providing valuable information for their sustainable management and for establishing adaptation strategies to the CC.Keywords: Port del Comte Massif; High-Mountain Karst Aquifer System, isotopes.

DOCTORAL DEGREE IN PHOTONICS

  • BERNARDELLO, MATTEO: Development of novel multimodal light-sheet fluorescence microscopes for in-vivo imaging of vertebrate organisms
    Author: BERNARDELLO, MATTEO
    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: 09/05/2022
    Reading date: 14/06/2022
    Reading time: 15:00
    Reading place: ICFO ¿ The Institute of Photonic Sciences - Campus Baix Llobregat - Av.
    Thesis director: LOZA ALVAREZ, PABLO | GUALDA MANZANO, EMILIO JOSE
    Committee:
         PRESIDENT: LORENZO, CORINNE
         SECRETARI: KRIEG, MICHAEL
         VOCAL: GONÇALVES MARTINS, GABRIEL JOSÉ
    Thesis abstract: The observation of biological processes in their native environments is of critical importance for life science. While substantial information can be derived from the examination of in-vitro biological samples, in-vivo studies are necessary to reveal the complexity of the dynamics happening in real-time within a living organism. Between the possible biological model choices, vertebrates represent an important family due to the various characteristics they share with the human organism. The development of an embryo, the effect of a drug, the interaction between the immune system and pathogens, and the cellular machinery activities are all examples of highly-relevant applications requiring in-vivo observations on broadly used vertebrate models such as the zebrafish and the mouse. To perform such observations, appropriate devices have been devised. Fluorescence microscopy is one of the main approaches through which specific sample structures can be detected and registered in high-contrast images. Through micro-injections or transgenic lines, a living specimen can express fluorescence and can be imaged through such microscopes. Various fluorescence microscopy techniques have been developed, such as Widefield Microscopy (WM) and Laser Scanning Confocal Microscopy (LSCM). In WM the entire sample is visualized in a single 2D image, therefore losing the depth information, while LSCM can recover the 3D information of the sample but with inherent limitations, such as phototoxicity and limited imaging speed. In the last two decades, Light-Sheet Fluorescence Microscopy (LSFM) emerged as a technique providing fast and 3D imaging, while minimizing collateral damages to the specimen. However, due to the particular configuration of the microscope¿s components, LSFM setups are normally optimized for a single application. Also, sample management is not trivial, as controlling the specimen positioning and keeping it alive for a long time within the microscope needs dedicated environmental conditioning. In this thesis, I aimed at advancing the imaging flexibility of LSFM, with particular attention to sample management. The conjugation of these aspects enabled novel observations and applications on living vertebrate samples. In Chapter 1, a brief review of the concepts employed within this thesis is presented, also pointing to the main challenges that the thesis aims to solve.In Chapter 2, a new design for multimodal LSFM is presented, which enables performing different experiments with the same instrument. Particularly, high-throughput studies would benefit from this imaging paradigm, conjugating the need for fast and reproducible mounting of multiple samples with the opportunity to image them in 3D. Additionally, from this design, a transportable setup has also been implemented.With these systems, I studied the dynamics of the yolk¿s microtubule network of zebrafish embryos, describing novel features and underlining the importance of live imaging to have a whole view of the sample¿s peculiarities. This is described in Chapter 3.Further applications on challenging live samples have been implemented, monitoring the macrophage recruitment in zebrafish and the development of mouse embryos. For these applications, described in Chapter 4, I devised specific mounting protocols for the samples, keeping them alive during the imaging sessions.In Chapter 5, an additional LSFM system is described, which allows for recording the sub-cellular machinery in a living vertebrate sample, while avoiding its damage thanks to the devised sample mounting. Through this, single-molecule microscopy (SMM) studies, normally performed on cultured cells, can be extended to the nuclei of living zebrafish embryos, which better recapitulate the native environment where biological processes take place.Finally, Chapter 6 recapitulates the conclusions, the impacts, future integrations, and experimental procedures that would be enabled by the work resumed in this th
  • DE ROQUE FERNANDEZ, PABLO MANUEL: Contributions to nanophotonics: linear, nonlinear and quantum phenomena
    Author: DE ROQUE FERNANDEZ, PABLO MANUEL
    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: 06/04/2022
    Reading date: pending
    Reading time: pending
    Reading place: pending
    Thesis director: VAN HULST, NIEK
    Committee:
         PRESIDENT: QUIDANT, ROMAIN
         SECRETARI: PAPADAKI, GEORGIA
         VOCAL: AIZPURUA IRIAZABAL, JAVIER
    Thesis abstract: Nanophotonics can be defined as the science and technology studying the control optical fields at the nanoscale and their interaction with matter. In order to spatially control such fields we would need structures with characteristic dimensions of the order of the wavelength, bringing us to the nanoscale. A way to control optical fields at this scale is the use of nanoantennas, optical equivalent of radio-antennas. They provide efficient interfaces between near-fields generated by light sources and radiative channels. After a brief Introduction, Chapter 2 describes interaction between single photon emitters and nanoantennas. We start the chapter introducing a method to numerically simulate the interaction. A key concept to solving Maxwell equations is that of the Green function. I show how this function relates to the emission rate of optical emitters in a nanophotonic environment. I then describe an our efforts to build a lifetime-imaging near-field scanning optical microscope. Using this rig we are able to measure changes changes in the emission rate of single emitters that interact with resonant optical antennas. A complementary way to control optical field in the nanoscale is using dielectric confinement. Chapter 3 introduces hybrid structures combining nanoantennas and dielectric waveguides. I generalize the Green function formalism introduced in Chapter 2, and show how this is related to the energy transfer rate between a donor and an acceptor. I use this numerical method to calculate the energy transfer rate in a hybrid structure. An increase of orders of magnitude is found at distances of the order of the wavelengths of the transferred photons. This chapter finishes by discussing the role that the local density of optical states has on the energy transfer efficiency.Nanoantennas increase near-field by orders of magnitude. In these conditions, nonlinear optical effects start to play a role. Chapter 4 is devoted to these nonlinear interactions mediated by nanoantennas. I explore nonlinear interactions in resonant nanoantennas, in particular SHG. First I introduce a method to numerically compute the contributions to SHG generated by the metal in nanoantennas. Both surface and bulk contributions to SHG are considered. I use the numerical method to show that narrowings within the antenna shape are sources of increased SHG. The increase in SHG is attributed to increase of the local field gradients, that increase to the bulk contribution to SHG. We numerically validate our results by performing SHG measurements at the single resonant antenna level.Optical fields are functions of space, but also of time. The development of broadband femtosecond lasers and pulse shaping techniques allows control of optical field down to the femtosecond timescale. Chapter 5 explores the control of optical fields in time. Using phase shaping methods we optimize the two-photon absorption process in single QDs. I introduce a new optimization algorithm, that allows us to perform the optimization using as feedback signal the luminesce from single QDs. We then compare our results with standard phase shaping techniques.Based on their success to effectively control all kinds of optical fields, plasmon supporting nanoantennas are being actively researched in the field of quantum optics. In Chapter 6 I describe a quantum eraser experiment mediated by structures supporting surface plasmon resonances. I first explain the details and subtleties of a quantum eraser experiment. I then detail our efforts to reproduce previously reported results about how to fabricate elliptical bullseye antennas behaving as quarter waveplates. Quarter waveplates are a required part for the quantum eraser effect to take place. An additional key component of our experiment is a bright, state-of-the-art entangle polarization entangle photon source that is described at length. We then perform a quantum eraser experiment mediated by plasmons.
  • ROMBAUT SEGARRA, JUAN: Multifunctional optical surfaces for optoelectronic devices
    Author: ROMBAUT SEGARRA, JUAN
    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: Temporary seizure
    Deposit date: 25/02/2022
    Reading date: pending
    Reading time: pending
    Reading place: pending
    Thesis director: PRUNERI, VALERIO
    Committee:
         PRESIDENT: MANNELLI, ILARIA
         SECRETARI: MARTORELL PENA, JORDI
         VOCAL: ST CLAIR, TODD PARRISH
    Thesis abstract: Highly transparent optical surfaces with anti-reflection (AR) and self-cleaning properties have the potential to increase performance in a wide range of applications, such as display screens, photovoltaic cells or sensors. Nature has provided numerous examples of biological systems with interesting functionalities that have high commercial interest, from the broadband and omnidirectional anti-reflection effect created by the tiny nanopillars found on the corneas of moths¿ eyes, to the self-cleaning behaviour of lotus leaves generated by micro-and nanoprotuberances. However, despite intense academic research, replicating such elaborate nanostructures for mass-production remains a major challenge due to the limitations of the existing nanofabrication techniques based on classical optical and e-beam lithography processes. This thesis is devoted to the study of bio-inspired multifunctional nanostructured surfaces with enhanced optical and wetting properties for use in optoelectronic devices. Novel and reliable manufacturing techniques are proposed for patterning organic and inorganic materials with high precision and throughput, aiming to bring this technology out of the laboratory and making it industrially viable. The first part of this study has been centred on glass, as it is one of the most widely used materials for optoelectronic devices. Chapter 3 presents a nanopillar structure created on glass substrates, which provides high anti-reflective properties, enhanced transmission, superhydrophobicity, and high mechanical resistance against external agents. The proposed manufacturing method permits moderate tunability to adapt the structure to the requirements of different applications. The design and optimisation of the fabrication process and a full characterisation of the samples are reported. Chapter 4 describes the combination of two different anti-reflective approaches, state-of-the-art multilayer (ML) anti-reflective coatings and self-cleaning biomimetic nanostructures (NS). The classical ML coating, relying on destructive interference from multiple reflections at layer interfaces is capable of providing excellent AR properties, but with a limited wavelength range and angular acceptance. In addition, it has limited hydrophobicity and self-cleaning properties due to its flat surface. The NS coating can provide broad wavelength and angular AR properties, as well as superhydrophobicity. However, it suffers from mechanical durability issues. In this work, the combination of both methods is presented as an innovative solution, combining greater anti-reflective operational wavelength and angular acceptance, self-cleaning properties, and high mechanical durability. A nanostructured design for transparent oleophobic surfaces is investigated and experimentally demonstrated in Chapter 5. Two new fabrication techniques to create nanocavities on glass are presented. The nanohole structure can repel oil and other low surface tension liquids, and a new wetting model is developed to theoretically explain the mechanism. The porous structure modifies the effective refractive index of the nanostructured layer between the air and the glass, creating an AR effect. The samples present higher transmission, as well as low scattering due to the subwavelength size of the cavities. In addition, the geometry of the surface offers higher mechanical resistance compared to nanopillars, widening the potential applications where it could be used. Finally, in Chapter 6, a new method to nanostructure organic materials with high resolution is presented. Nanostructured thin polyimide films on top of glass surfaces can act as an anti-reflective coating, while adding protection and hydrophobicity. A practical example is demonstrated with transparent electrodes made of Indium Tin Oxide. By covering a surface with nanostructured polyimide, the overall optical response can be improved while its electric properties are protected by the polymeric film.

DOCTORAL DEGREE IN POLYMERS AND BIOPOLYMERS

  • MARTÍNEZ CUTILLAS, ALFREDO: Poly(lactic acid) blends and copolyesters with advanced properties for biomedical applications
    Author: MARTÍNEZ CUTILLAS, ALFREDO
    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: Confidentiality
    Deposit date: 25/04/2022
    Reading date: 13/06/2022
    Reading time: 11:00
    Reading place: ETSEIB Sala d'Audiovisuals del Dept. d'Enginyeria Química (ETSEIB, Diagonal, 647, Pavelló G, 2a planta, 08028 Barcelona, Campus Sud)
    Thesis director: MARTINEZ DE ILARDUYA SAEZ DE ASTEASU, DOMINGO | OH, SEJIN
    Committee:
         PRESIDENT: GARCÍA MARTÍN, MARÍA DE GRACIA
         SECRETARI: GARCIA ALVAREZ, MONTSERRAT
         VOCAL: ETXEBERRIA LIZARRAGA, AGUSTÍN
    Thesis abstract: Poly(lactic acid) (PLA) is a biobased, biodegradable and biocompatible polymer. Because of that, it is a polymer that generates a great interest in the research and development of new advanced materials. Among the current cutting-edge technologies, PLA is particularly a great candidate for the preparation of biomedical devices such as temporary implants for tissue regeneration. Nevertheless, neat PLA solutions cannot fulfil the requirements of a temporary implant, thus it has to be modified. That was the main purpose of this Thesis. Study how different modifications influenced PLA degradation rate, mechanical properties or cell affinity. With that aim, PLA-based blends and copolymers were prepared. All of them were extensively characterized in their more relevant physicochemical properties. Finally, the best candidates were selected to prepare functionalized scaffolds for their in vitro evaluation.In the first part of the Thesis is reported the synthesis of PLLA by ring-opening polymerization (ROP) of L-lactide under different temperatures, catalyst concentration and initiator conditions. Once the optimal reaction conditions were determined, a series of PLAs were synthetized using different concentrations of L-lactide and D-lactide isomers. These PLAs were useful to study the influence of stereoregularity on the thermal properties, the mechanical properties and the hydrolytic degradation rate of film samples. That evaluation brought out the brittle fracture of all the PLAs and the faster degradation of those heterotactic PLAs.To improve the mechanical properties of PLA, a series of triblock copolymers with A-B-A structure and varied composition of A and B were synthetized, being A referred to PLA blocks and B to polymacrolactones blocks. The triblock copolymers weresynthetized in two steps. In the first one polymacrolactones were synthesized by enzymatic ROP of unsaturated macrolactones such as globalide (Gl) and 6-¿ hexadecenlactone (6HDL) using 1,4-butanediol as initiator. Then, polyglobalide (PGl) and poly(6-¿-hexadecenlactone) (P6HDL) were used as initiators in the ROP of lactide. The triblock structure of the copolymers was validated by the different characterization techniques employed. Moreover, a wide range of mechanical properties was achieved in dependence of A and B blocks composition.As an alternative to triblock copolymers, a series of PLLA and PGl blends were prepared by melt-extrusion and solvent- casting. To reduce the interfacial tension between both polymers, a fraction a of triblock copolymer was added ascompatibilizer to some selected samples. However, the great incompatibility of the components resulted in poor mechanical properties.After this initial evaluation, it was concluded that triblock copolymers were the right solution. Among all the synthetized triblock copolymers, the best candidates were selected for further functionalization. Hydroxyl terminal groups of the copolymers were esterified with modified PEG chains containing carboxyl terminal groups. These PEG-functionalized copolymers were used to prepare scaffolds by a solvent casting/particulate leaching method. Porosity was generated by controlled-size NaCl particles, which were removed by water washing. Scaffolds were functionalized with RGD tripeptide (arginine-glycine-aspartate) to enhance their cell adhesion. Evaluation in vitro confirmed these scaffolds functionalized with PEG and RGD peptides were not cytotoxic to cells and improved cell adhesion and proliferation of two cell cultures.In parallel, it was investigated the enzymatic cyclodepolymerization of the polymacrolactones and the triblock copolymers into macrocyclic oligoesters, and their subsequent repolymerization. This chemical recycling method could be an effective route for the recovering of the monomer species from the copolymers if they are used in other applications such as microelectronics or agriculture.

DOCTORAL DEGREE IN SIGNAL THEORY AND COMMUNICATIONS

  • PORTAL GONZALEZ, GERARD: Synergistic optical and microwave remote sensing approaches for soil moisture mapping at high resolution
    Author: PORTAL GONZALEZ, GERARD
    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: Temporary seizure
    Deposit date: 20/04/2022
    Reading date: 27/05/2022
    Reading time: 11:00
    Reading place: ETSETB - Aula Teleensenyament - Campus Nord UPC.
    Thesis director: VALL-LLOSSERA FERRAN, MERCEDES MAGDALENA | PILES GUILLEM, MARIA
    Committee:
         PRESIDENT: ZRIBI, MEHREZ
         SECRETARI: DUFFO UBEDA, NURIA
         VOCAL: MONTZKA, CARSTEN
    Thesis abstract: Soil moisture is an essential climate variable that plays a crucial role linking the Earth¿s water, energy, and carbon cycles. It is responsible for the water exchange between the Earth¿s surface and the atmosphere, and provides key information about soil evaporation, plant transpiration, and the allocation of precipitation into runoff, surface flow and infiltration. Therefore, an accurate estimation of soil moisture is needed to enhance our current climate and meteorological forecasting skills, and to improve our current understanding of the hydrological cycle and its extremes (e.g., droughts and floods). L-band Microwave passive and active sensors have been used during the last decades to estimate soil moisture, since there is a strong relationship between this variable and the soil dielectric properties.Currently, there are two operational L-band missions specifically devoted to globally measure soil moisture: the ESA¿s Soil Moisture and the Ocean Salinity (SMOS), launched in November 2009; and the NASA¿s Soil Moisture Active Passive (SMAP), launched in January 2015. The spatial resolution of the SMOS and SMAP radiometers, in the order of tens of kilometers (~40 km), is adequate for global applications. However, to fulfill the needs of a growing number of applications at local or regional scale, higher spatial detail (< 1 km) is required. To bridge this gap and improve the spatial resolution of the soil moisture maps, a variety of spatial enhancement or spatial (sub-pixel) disaggregation approaches have been proposed.This Ph.D. Thesis focuses on the study of the Earth¿s surface soil moisture from remotely sensed observations. This work includes the implementation of several soil moisture retrieval techniques and the development, implementation, validation and comparison of different spatial enhancement or downscaling techniques, applied at local, regional, and continental scale. To meet these objectives, synergies between several active/passive microwave sensors (SMOS, SMAP and Sentinel-1) and optical/thermal sensors (MODIS) have been explored. The results are presented as follows:- Spatially consistent downscaling approach for SMOS using an adaptive moving windowA passive microwave/optical downscaling algorithm for SMOS is proposed to obtain fine-scale soil moisture maps (1 km) from the native resolution (~40 km) of the instrument. This algorithm introduces the concept of a shape-adaptive window as a central improvement of the disaggregation technique presented by Piles et al. (2014), allowing its application at continental scales. - Assessment of multi-scale SMOS and SMAP soil moisture products across the Iberian PeninsulaThe temporal and spatial characteristics of SMOS and SMAP soil moisture products at coarse- and fine-scales are assessed in order to learn about their distinct features and the rationale behind them, tracing back to the physical assumptions they are based upon.- Impact of incidence angle diversity on soil moisture retrievals at coarse and fine scales An incidence angle (32.5°, 42.5° and 52.5°)-adaptive calibration of radiative transfer effective parameters single scattering albedo and soil roughness has been carried out, highlighting the importance of such parameterization to accurately estimate soil moisture at coarse-resolution. Then, these parameterizations are used to examine the potential application of a physically-based active-passive downscaling approach to upcoming microwave missions, namely CIMR, ROSE-L and Sentinel-1 Next Generation. Soil moisture maps obtained for the Iberian Peninsula at the three different angles, and at coarse and fine scales are inter-compared using in situ measurements and model data as benchmarks.

DOCTORAL DEGREE IN SUSTAINABILITY

  • BERMEJO PLANA, DAVID: Experimental investigation of the influence of hydrodynamic cavitation on heat generation
    Author: BERMEJO PLANA, 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 SUSTAINABILITY
    Department: University Research Institute for Sustainability Science and Technology (IS.UPC)
    Mode: Temporary seizure
    Deposit date: 28/03/2022
    Reading date: 02/06/2022
    Reading time: 15:00
    Reading place: ETSECCPB Aula 001 Edifici C2 - UPC CAMPUS NORD - Carrer de Jordi Girona, 1, 3, 08034 Barcelona - videoconferència enllaç: meet.google.com/why-qmob-ddt
    Thesis director: RUIZ MANSILLA, RAFAEL | ESCALER PUIGORIOL, FRANCESC XAVIER
    Committee:
         PRESIDENT: RUDOLF, PAVEL
         SECRETARI: CORTINA PALLAS, JOSE LUIS
         VOCAL NO PRESENCIAL: DULAR, MATEVZ
    Thesis abstract: The fresh water scarcity has become a concern for societies as a result of the scientific evidence about climate change and the intensive human activities. Thermal separation is one of the best available techniques for waste water treatment where the pollutants are removed from wastewaters by evaporating the water at the expense of large amounts of energy. In many industries there is no access to heat waste, thus a clean source of energy is required. The so-called hydrodynamic heat generators are claimed as high efficiency heating devices, avoiding scaling by warming liquids without transfer surfaces with the help of cavitation effects. However, neither the heat transfer mechanisms nor the amount of energy released to the surrounding liquid have been sufficiently understood yet. Based on this, the objective of the thesis has been to investigate the effects of cavitation on heating processes confirm the generation of heat in cavitating hydraulic systems and quantify the energy released by cavitation. The produced knowledge about the heat transfer mechanisms and the behaviour of cavitation in heat processes helps to assess the design of hydrodynamic heat generators. For that, an experimental approach has been adopted in a new test rig devoted to study the macroscale thermodynamic effects of attached sheet cavitation developed inside an ad hoc converging-diverging pipe with asymmetric rectangular cross section. This cavitation tunnel has been equipped with a control system to set a wide range of stable flow conditions by means of the centrifugal pump rotating speed and the opening ratio of a control valve. A pneumatic system has permitted to modify the reference pressure and a data acquisition system is used to record the operating parameters such as the pressures, temperatures and pump electrical power consumption and rotating speed. Initially, a series of short-term tests at non-cavitating and cavitating regimes have been performed to map the operation of the test rig and the flow behaviour at the test section. During these tests, the cavitation morphology and dynamic behaviour has been identified and measured with the help of high-speed video recording. Then, a series of long-term tests have been conducted at homologous pump¿s operating points at non-cavitating and cavitating regimes to compare the heat generation between them. The obtained results have demonstrated that the cavitation flow behaviour inside the Venturi-like test section along the full operating range of the closed loop pumping system is in good agreement with previous studies. Moreover, the behaviour of the cavitating flow has been found similar to that exhibited by chocked compressible gas flows: the static pressure at the inlet section rises as flow rate increases while the cavitation number remains constant. Thus, the pressure at the inlet section becomes proportional to the dynamic pressure at the throat with the inception and development of cavitation. On the basis of these observations, a new flow coefficient has been derived which remains constant at any cavitating regime. In relation to the temperature effects, the results have demonstrated a linear dependency of the rising temperature rate with the generated hydraulic power. However, no evidence has been found confirming that the presence of cavitation inside the test section influences significantly the rising temperature rates when homologous operating points at non-cavitating and cavitating regimes are compared. Contrarily, only the external temperature has been found to play an important role in the heating process.
  • GUADARRAMA FUENTES, OMAR VICENTE: Un enfoque holísitico para evaluar la Sostenibilidad de las Indicaciones Geográficas: una aplicación a las DOP de aceite en Cataluña
    Author: GUADARRAMA FUENTES, OMAR VICENTE
    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: Normal
    Deposit date: 07/04/2022
    Reading date: 01/06/2022
    Reading time: 12:30
    Reading place: EEAB- Sala de Graus de l'EEABB (Campus de Castelldefels)
    Thesis director: GIL ROIG, JOSE MARIA
    Committee:
         PRESIDENT: BELLETTI, GIOVANNI
         SECRETARI: KALLAS CALOT, ZEIN
         VOCAL: BRUGAROLAS MOLLA-BAUZA, MARGARITA MARÍA
    Thesis abstract: The importance of Geographical Indications (GI) has grown considerably in recent years as an opportunity for product differentiation for specific segments of the population. The continuous increase in the number of certified products, as well as their growing economic importance, has determined that the scientific literature has found in this type of products an interesting source of inspiration. Much of the recent literature has focused on analysing the sustainability of these production systems from an economic, social and environmental point of view. However, few studies have addressed the overall sustainability of GIs by adopting a holistic and multidimensional approach. Taking into account the existing limitations in the literature, the main contribution of this thesis has been to develop a methodological approach to assess the sustainability of agri-food production systems linked to GIs, based on three criteria: holistic approach, ability to resolve conflicts between indicators, and ease of monitoring. In addition, the aim is to offer a tool that facilitates the development of strategic plans for GIs to improve their sustainability commitments to society. To achieve this objective, this Thesis has been structured in three chapters. Chapter 2 analyses and prioritizes the main discourses that have been generated in the literature on GIs using the Q-Methodology. The chapter reviews the literature on GIs and concludes that the main discourses surrounding GIs are articulated along three axes: governance, differentiated product quality, and contribution to territorial development. Chapter 3 reviews the existing literature on sustainability indicators and develops a methodological proposal that includes 36 individual indicators and a synthetic indicator. This synthetic indicator is calculated using the Fuzzy Hierarchical Analytical Process based on the opinions of 55 experts related to GIs (Regulatory Councils, heads of Public Administrations and researchers). A tool is also designed to assess the strategic positioning of GIs. Chapter 4 presents the application of the approach analysed in Chapter 3 to the five-olive oil PDOs in Catalonia (Baix Ebre and Montsià, Garrigues, Empordà, Siurana and Terra Alta). The results indicate a very satisfactory level of sustainability in the five PDOs analysed, although with potential for improvement in the environmental pillar. The thesis ends with Chapter 5, which includes the main conclusions of the results obtained, a self-critical review of the work and suggestions for future lines of research. Keywords: Sustainable geographical indications; Arguments of the GI discourse; Synthetic sustainability indicator.

ERASMUS MUNDUS DOCTORAL DEGREE IN INFORMATION TECHNOLOGIES FOR BUSINESS INTELLIGENCE

  • HEWASINGHAGE, MODITHA LAKSHAN DHARMASIRI: Physical database design in document stores
    Author: HEWASINGHAGE, MODITHA LAKSHAN DHARMASIRI
    Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
    Programme: ERASMUS MUNDUS DOCTORAL DEGREE IN INFORMATION TECHNOLOGIES FOR BUSINESS INTELLIGENCE
    Department: Department of Service and Information System Engineering (ESSI)
    Mode: Change of supervisor
    Deposit date: 04/04/2022
    Reading date: 12/07/2022
    Reading time: 09:00
    Reading place: FIB- Sala d'Actes Manuel Martí Recober - FIB
    Thesis director: ABELLO GAMAZO, ALBERTO | VARGA, JOVAN | ZIMANYI BORRAGEIROS, ESTEBAN
    Committee:
         PRESIDENT: WREMBEL, ROBERT
         SECRETARI: BADIA FLORENSA, ANTONIO
         VOCAL NO PRESENCIAL: ZISSIS, DIMITRIS
    Thesis abstract: NoSQL is an umbrella term used to classify alternate storage systems to the traditional Relational Database Management Systems (RDBMSs). Among these, Document stores have gained popularity mainly due to the semi-structured data storage model and the rich query capabilities. They encourage users to use a data-first approach as opposed to a design-first one. Database design on document stores is mainly carried out in a trial-and-error or ad-hoc rule-based manner instead of a formal process such asnormalization in an RDBMS. However, these approaches could easily lead to a non-optimal design resulting additional costs in the long run.This PhD thesis aims to provide a novel multi-criteria-based approach to database design in document stores. Most of such existing approaches are based on optimizing query performance. However, other factors include storage requirement and complexity of the stored documents specific to each use case. There is a large solution space of alternative designs due to the different combinationsof referencing and nesting of data. Thus, we believe multi-criteria optimization is ideal to solve this problem. To achieve this, weneed to address several issues that will enable us to apply multi-criteria optimization for the data design problem.First, we evaluate the impact of alternate storage representations of semi-structured data. There are multiple and equivalent ways tophysically represent semi-structured data, but there is a lack of evidence about the potential impact on space and query performance. Thus, we embark on the task of quantifying that precisely for document stores. We empirically compare multiple waysof representing semi-structured data, allowing us to derive a set of guidelines for efficient physical database design considering both JSON and relational options in the same palette.Then, we need a formal canonical model that can represent alternative designs. We propose a hypergraph-based approach for representing heterogeneous datastore designs. We extend and formalize an existing common programming interface to NoSQL systems as hypergraphs. We define design constraints and query transformation rules for representative data store types. Next, we propose a simple query rewriting algorithm and provide a prototype implementation together with storage statistics estimator.Next, we require a formal query cost model to estimate and evaluate query performance on alternative document store designs.Document stores use primitive approaches to query processing, such as relying on the end-user to specify the usage of indexes instead of a formal cost model. But we require a reliable approach to compare alternative designs on how they perform on a specific query. For this, we define a generic storage and query cost model based on disk access and memory allocation. As all documentstores carry out data operations in memory, we first estimate the memory usage by considering the characteristics of the storeddocuments, their access patterns, and memory management algorithms. Then, using this estimation and metadata storage size, we introduce a cost model for random access queries. We validate our work on two well-known document store implementations.The results show that the memory usage estimates have an average precision of 91% and predicted costs are highly correlated to the actual execution times. During this work, we also managed to suggest several improvements to document stores.Finally, we implement the automated database design solution using multi-criteria optimization. We introduce an algebra of transformations that can systematically modify a design of our canonical representation. Then, using them, we implement a local search algorithm driven by a loss function that can propose near-optimal designs with high probability. We compare our prototype against an existing document store data design solution. Our proposed designs have better performance and are more compact with less redundancy.

ERASMUS MUNDUS DOCTORAL DEGREE IN SIMULATION IN ENGINEERING AND ENTREPRENEURSHIP DEVELOPMENT

  • GARIKAPATI, HASINI: Computational uncertainity quantification in pressure-driven fracture processes
    Author: GARIKAPATI, HASINI
    Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
    Programme: ERASMUS MUNDUS DOCTORAL DEGREE IN SIMULATION IN ENGINEERING AND ENTREPRENEURSHIP DEVELOPMENT
    Department: (DECA)
    Mode: Change of supervisor
    Deposit date: 28/02/2020
    Reading date: pending
    Reading time: pending
    Reading place: pending
    Thesis director: DIEZ MEJIA, PEDRO | VAN BRUMMELEN, EINAR HARALD | VERHOOSEL, CLEMENS V. | ZLOTNIK MARTINEZ, SERGIO
    Committee:
         PRESIDENT: DE GOEY, PHILIP
         SECRETARI: NOBILE, FABIO
         VOCAL: DE LORENZIS, LAURA
    Thesis abstract: Uncertainty quantification is important in assessing and predicting the performance of complexengineering systems and processes, especially in the absence of adequate experimental or real-worlddata. With the increase in computing power, computational uncertainty quantification is playing anincreasingly important role in decision making processes. We have studied the application ofuncertainty quantification to pressure-driven fracture processes, which are surrounded by uncertaintyas data are typically scant and available models are often rudimentary.In this dissertation we have developed a computational framework that combines simulationtechniques for pressure-driven fracturing processes with state-of-the-art uncertainty quantificationtechniques. On the one hand, the framework simulates the influence of uncertainties in, for example,formation data, on quantities of interest such as the fracture length. On the other hand, the uncertaintyquantification framework allows us to incorporate indirect measurement data, such as well pressures,in the simulation procedure. The developed computational uncertainty quantification frameworkimproves the understanding of the influence of uncertainties on pressure-driven fracture processes.

NAUTICAL ENGINEERING, MARINE AND NAVAL RADIOELECTRONICS

  • UYA JUNCADELLA, AFRICA: Vessel Traffic Services, towards e-Navigation. The role of Oceanic VTS in Global Maritime Surveillance
    Author: UYA JUNCADELLA, AFRICA
    Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
    Programme: NAUTICAL ENGINEERING, MARINE AND NAVAL RADIOELECTRONICS
    Department: Department of Nautical Sciences and Engineering (CEN)
    Mode: Normal
    Deposit date: 25/04/2022
    Reading date: pending
    Reading time: pending
    Reading place: pending
    Thesis director: MARTINEZ DE OSÉS, FRANCISCO JAVIER
    Committee:
         PRESIDENT: CASTELLS SANABRA, MARCEL·LA
         SECRETARI: MARTÍNEZ MARÍN, JESÚS EZEQUIEL
         VOCAL: CUETO ANCELA, JOSÉ LUIS
    Thesis abstract: This thesis presents the study and analysis of the Vessel Traffic Services (VTS), from its origins to the present, with further evaluation of future trends. Examining the current trend in terms of technologies that are being applied in the maritime sector, the dissertation focuses on the future to draw a new paradigm. This envisages a scenario at a planetary level, following a single global traffic management system, which would create a model of the global VTS Operator. A new assignment is proposed, according to this third dimension, with Port VTS being the first level, the Coastal VTS second, and with the Oceanic VTS projected into the future, which is a substantial proposal. The foundation is based on EU projects, the most ambitious of which, currently underway, being Sea Traffic Management (STM), with a scope greater than Europe, and also on IALA VTS and ENAV Committee Working Groups, concerning the future of VTS. The study includes the reference documentation from the IMO, in resolution format, and that of the IALA, under Standards, Recommendations and Guidelines. From the first recognition of the IMO to the present, the guidelines for VTS have undergone three updates, which are analysed and compared. VTS are considered aids to navigation, AtoN, which contribute to safety of life at sea, safety and efficiency of navigation and protection of the marine environment, and are linked to ship traffic activity. Both their attributions and the implementation of VTS centres have increased over time. In addition to this, the evolution of the tools used by the VTS is examined, from its earliest stages with only two pieces of equipment, the VHF radio, and the radar. The VTS system began by looking at the air traffic model but, later, the maritime nature created necessary differentiation in terms of management and procedures. Digital technologies applied to the maritime sector take air traffic controllers¿ models as a reference, and the current VTS Operator profession will acquire analogies, such as sharing route plans and checking digital inputs. This highly specialised profession is facing the challenges of satellite technology, global interconnection, and the arrival of Maritime Autonomous Surface Ships (MASS). New technologies bring the possibility of sharing information and controlling traffic on a global scale, beyond the territorial sea, and this scenario will make standardisation increasingly necessary throughout the maritime sector. The identification of various models of traffic management, examination of systems operating specifically in the Spanish State and reflection on the diversity that prevails is also included. Based on fieldwork, the thesis determines that the future complexities that will emerge from maritime traffic will require exhaustive risk assessment and analysis. The challenges to be faced involve maritime communications via satellite and digital technology, in the context of `e-Navigation¿ (coined by the IMO), which will provide emerging tools, such as VDES (next generation of AIS), and a planetary-scale information exchange framework for VTS worldwide.

Last update: 25/05/2022 04:45:18.