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Theses authorised for defence

DOCTORAL DEGREE IN APPLIED MATHEMATICS

  • GATTI, FRANCESCA: Special values of the triple product p-adic L-function
    Author: GATTI, FRANCESCA
    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 APPLIED MATHEMATICS
    Department: Department of Mathematics (MAT)
    Mode: Normal
    Deposit date: 19/01/2021
    Reading date: 19/03/2021
    Reading time: 16:30
    Reading place: Facultat de Matemàtica i Estadística - UPC Campus Sud - Videoconferència: https://meet.google.com/ikv-ruuz-spt
    Thesis director: ROTGER CERDÀ, VICTOR
    Committee:
         PRESIDENT: XARLES, XAVIER
         SECRETARI: QUER BOSOR, JORDI
         VOCAL: LONGO, MATTEO
    Thesis abstract: Let E be an elliptic curve defined over the field of rational numbers and let f be the corresponding newform of weight 2. Let g,h be two weight one newforms whose nebentype characters are mutually inverse. Let V be the tensor product of the Artin representations attached to g and h, let L be the number field generated by the Fourier coefficients of g and h and let H be the number field cut by V. The points of E having coefficients in H form a finitely generated abelian group E(H), and one can attach to the pair (E,V) the finite-dimensional L-vector space MW(E,V) consisting of the homomorphisms from V to E(H) which are equivariant with respect to the action of the absolute Galois group of the rational numbers. We call algebraic rank of (E,V) the L-dimension of MW(E,V). On the other hand, a complex L-function L(E,V;s), which satisfies a functional equation whose center of symmetry is s=1, can be attached to (E,V). The Galois-equivariant version of the Birch and Swinnerton¿Dyer conjecture predicts that the algebraic rank of (E,V) should equal the order of vanishing of L(E,V;s) at s=1, that we call analytic rank of (E,V). An interesting approach to these sort of problems (which are in general still unsolved) is via p-adic analysis. In our setting, we will consider the triple product p-adic L-function Lp(F,G,H)(k,l,m) attached by Darmon and Rotger to a triple of Hida families F,G,H passing through f,g,h respectively at weights 2,1,1. The function Lp(F,G,H)(k,l,m) interpolates p-adically the central values of the complex L-functions attached to the specialisations of the families F,G and H at classical weights k,l,m for which the weight l is greater or equal to the sum of the other two (in this case we say that l is ¿dominant¿). In particular, the triple (2,1,1), which corresponds to the pair (E,V) lies outside the region of classical interpolation of the triple product L-function. In this thesis we study the value Lp(F,G,H)(2,1,1), and more in general the values of Lp(F,G,H) at weights (k,l,m) with k dominant, in different settings. n the case in which the ranks of (E,V) are 2, with the elliptic Stark conjecture Darmon, Lauder and Rotger predict (and prove, in some special cases) that Lp(F,G,H)(2,1,1) can be expressed as a p-adic regulator involving the p-adic logarithm of points on E(H), divided by the logarithm of a so- called Stark unit. We generalise this conjecture to general weights (k,l,m) with k dominant and we prove some cases of this conjecture. Here p is an odd prime which does not divide the conductors of g and h and divides at most once the conductor of E. If p does not divide any of the conductors and if the analytic and the alge- braic ranks of (E,V) are 0 we prove, under the additional hypothesis that the Selmer group of (E,V) is trivial, a formula for the value Lp(F,G,H)(2,1,1) in terms of the Bloch¿Kato logarithm of a canonical non-cristalline class which belongs to the p-relaxed Selmer group of (E,V), along a certain cristalline direction. As a corollary we prove that, in the special case in which g and h are theta series of Hecke characters of the same imaginary quadratic field in which p splits, the triple product L-function vanishes at (2,1,1). Finally we study the case in which E has multiplicative reduction at p, g and h are theta series of the same imaginary quadratic field K in which p is inert, p does not divide the conductors of g and h and the analytic rank of (E,V) is 0. In this setting, Bertolini and Darmon constructed a so¿called Kolyvagin class with interesting arithmetic properties, which lies in the relaxed Selmer group of E over the field H cut out by V. We prove a formula which relates the value Lp(F,G,H)(2,1,1) to the p-adic logarithm of the projection along a cristalline direction of the Kolyvagin class.

DOCTORAL DEGREE IN ARCHITECTURAL DESIGN

  • NAEIMI, TAHMINEH: Urban Park a New Typology of Built-Up Nature: Towards a New Urban Green Language for Barcelona
    Author: NAEIMI, TAHMINEH
    Thesis file: (contact the Doctoral School to confirm you have a valid doctoral degree and to get the link to the thesis)
    Programme: DOCTORAL DEGREE IN ARCHITECTURAL DESIGN
    Department: Department of Architectural Design (PA)
    Mode: Normal
    Deposit date: 30/11/2020
    Reading date: 19/03/2021
    Reading time: 09:00
    Reading place: Sala de Graus ETSAB - UPC Campus Sud - Av Diagonal 649
    Thesis director: GONZALEZ RAVENTOS, AQUILES | LLOBET RIBEIRO, XAVIER
    Committee:
         PRESIDENT: GAUSA NAVARRO, MANUEL
         SECRETARI: FERRER FORES, JAIME JOSE
         VOCAL: RUBERT DE VENTOS, MARIA
         VOCAL: FREDIANI I SARFATI, ARTURO
         VOCAL: MUNAR BAUZA, MARGARITA
    Thesis abstract: This thesis aims to generate a new vision for the park division and introduce a new model of parks called Urban Park. Urban Park should follow specific features and unique characteristics that made it suitable to be integrated into any urban fabric. Therefore, a study on the available groups of parks helps the thesis to compare their characteristics and facilities and formulate a complex of design principles for urban Park. It helps the study to go through formulating a flexible architectural model for Urban Park that can respond to the current and future needs of the inhabitant. This thesis is composed of three chapters that generally are studying on three periods in park design as former time, modern time, and the present time. The first chapter based on bibliographical research leads the thesis to study the concept of paradise and relates it to gardens. Historiography and itinerary review clarifies that the first signs of the park from the current vision date back to 500BC in the Persian Empire that created gardens with the concept of paradise. It clarifies that those gardens were royal and private gardens that were open to the public sporadically in local and national festivals, events, and holidays. The characteristics and elements of the Persian paradises made them a reference for the western world for centuries. Comparing and analyzing Persian gardens helped the thesis to find important and structural elements of these parks that served to illuminate those other characteristics of the contemporary urban park.The second chapter refers to modern times and begins with the first public park that broke the boundaries of the symmetrical design that had been implemented by the Persian garden model and offers a new attitude to park design. A comparison of the case studies shows the evolution of public parks to urban parks. Study and comparison of the plan of Randel for Manhattan and the plan of Cerdà for Barcelona clarify fundamental elements of the urban renewal of these two urban fabric. Moreover, analyzing the evolution of greenery in Barcelona and Manhattan, and also different techniques of redrawing Central Park and urban blocks of both cities served as fundamental references to clarify the idea of what an urban park is. Besides, it also helps the thesis to differentiate an Urban Park from a green park and enlighten the characteristics of the contemporary Urban Parks. The third and final chapter studies the present moment and tries to introduce a green pattern for the built cities. Therefore, it took as reference the two urban models of Kevin Lynch as Star model and Galaxy model. According to the purpose of the thesis and also based on the information obtained from analyzing Kevin Lynch's selected models the thesis introduced the Star-Galaxy model. The new model is containing characteristics that are the basis of the contemporary Urban Park model. Moreover, this chapter clarifies the characteristics of the modern metropolis with its relation to urban nature and select Barcelona as a reference. This chapter opens a new vision of Barcelona city with the maximum expression of the relationship between the urban fabric of metropolises and nature. It explains the characteristics of the new system of urban greenery and introduced the new Urban Park of the Plaça de Les Glòries. At the end of this tour of the parks from the Persian era to the present day transferring all the data coming out from research methodologies into a theory had been done. It can be purposed that the model being implemented in Barcelona urban fabric can be considered as a contemporary model for Urban Parks. It opens a vision to the new generation of urban greenery system and can be considered as a reference for further interventions in metropolises.

DOCTORAL DEGREE IN AUTOMATIC CONTROL, ROBOTICS AND VISION

  • MONTAÑO SARRIA, ANDRES FELIPE: Object Manipulation Based on Tactile Information
    Author: MONTAÑO SARRIA, ANDRES FELIPE
    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 AUTOMATIC CONTROL, ROBOTICS AND VISION
    Department: Institute of Industrial and Control Engineering (IOC)
    Mode: Normal
    Deposit date: 01/02/2021
    Reading date: 18/03/2021
    Reading time: 11:00
    Reading place: Sala de reunions IOC, Planta 1, Escola Tècnica Superior d'Enginyeria Industrial de Barcelona (ETSEIB), Avinguda Diagonal, 647, 08028 Barcelona Enllaç Google meet: meet.google.com/hsf-souy-qop
    Thesis director: SUAREZ FEIJOO, RAUL
    Committee:
         PRESIDENT: INDRI, MARINA
         SECRETARI: ROSELL GRATACOS, JOAN
         VOCAL: ROA, MAXIMO A.
    Thesis abstract: In-hand dexterous manipulation of an object is the ability to change the configuration (position and/or orientation) of an object held in the hand. This is an ability that has allowed humans to use tools and interact with the environment effectively.For the past decades, robotics researchers have worked to provide dexterous manipulation skills to the robots by designing robotic hands that mimic the human hand and by developing applications that allow performing autonomous manipulation or teleoperation in harsh environments. Despite the progress made, managing the uncertainties that exist in the real world is one of the problems that still need to be worked on. Many existing manipulation methods for controlling robotic hands require a priori information about the object and high-fidelity sensors that are typically limited only to laboratory settings.The main objective of this thesis is to develop strategies for the dexterous manipulation of unknown objects, using the tactile information generated during the grasp of the object and the manipulation process itself. In manipulation applications based on tactile information, the robotic hand has access only to tactile and proprioceptive data, in addition, no a priori information is known about the manipulated object. This reflects real-world applications, where there is uncertainty in the models of the objects that are commonly manipulated in daily activities, as well as in the sensorial measurements.In this dissertation, novel manipulation strategies based on heuristic and gradient optimization methods are proposed.Three quality indexes are selected to measure the goodness of the grasp during the manipulation, related to the configuration of the hand, the quality of the grasp, and the configuration of the object. Starting from a given initial grasp, the manipulation strategies are able to improve one quality index or a combination of them. The manipulation strategies are validated with real experimentation using robotic hands equipped with tactile sensors, allowing the execution of practical applications, such as object recognition, force optimization, and telemanipulation.

DOCTORAL DEGREE IN CIVIL ENGINEERING

  • GONZALEZ GUZMAN, CARLOS ALBERTO: REDISTRIBUCIÓN DEL USO DEL ESPACIO VIARIO COMO GESTOR EFICIENTE DE LA MOVILIDAD
    Author: GONZALEZ GUZMAN, CARLOS ALBERTO
    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: 01/02/2021
    Reading date: 18/03/2021
    Reading time: 16:30
    Reading place: VIDEOCONFERENCIA Estat alarma Covid-19 - ETSECCPB, aula C2-001, Campus Nord, C/ Jordi Girona 1-3, 08034 BCN - enllaç: meet.google.com/pfg-eqyp-xk
    Thesis director: ROBUSTÉ ANTÓN, FRANCESC
    Committee:
         PRESIDENT: MONZÓN DE CACERES, ANDRÉS
         SECRETARI: ESTRADA ROMEU, MIGUEL ANGEL
         VOCAL: SARMIENTO ORDOSGOITIA, IVÁN REINALDO
    Thesis abstract: The efficient and equitable use of urban road space considered as a public good and a scarce resource, leads to giving priority to sustainable transport modes (walking, cycling and public transport). Private vehicle sees its space reduced due to its negative externalities (space consumption, in addition to pollution, noise, accidents, barrier effect, etc.).This trend is international and has been applied progressively since the last decades (with the time lag and graduation conditioned by the prevailing type of local urban planning). It still does not have a methodological formulation that brings the scientific support: decisions are made on the political ground or based on "road/street supply models", which do not always have technical background.This thesis develops the conceptual and methodological bases of an alternative mobility management instrument called ¿ Road Space Retribution Charge by Congestion Costs¿. We obtain the quantity (supply) of urban road space currently used by the private vehicle that must be transferred to sustainable transport modes using principles of transportation microeconomics. In a similar way but a century ago, Pigou formulated a tax to internalize the traffic congestion externalities.The restriction of space to vehicular traffic entails increases in travel times for the private vehicle, but even so it can favor the global mobility of the city: alternative modes enjoy more space for exclusive use and increase their commercial speed and their modal share, while the remaining traffic can be reassigned in the network more efficiently. The social welfare improves and the disincentive in the use of the private vehicle is similar to the Pigouvian tax.The methodological development is applied to the historic center of Santiago de Cali (Colombia), resulting in that a hybrid scheme of "Reallocation of the Use of Road Space" and "Traffic Management and Control" is the most appropriate for the internalization of externalities due to congestion.The results of the practical application suggest that the social benefits of the desirable scenario with respect to the baseline scenario include a 26% reduction in polluting emissions and an increase of 52 percentage points in the participation of sustainable transport modes in the use of urban road space.The research carried out finds general application in cities or parts of them that intend to humanize and recover part of the space currently occupied by the wheeled traffic of private vehicles. It can also be used to decide to implement urban projects such as ¿ super-blocks¿ (restriction of access and through traffic in few contiguous blocks) or in embodiments of ¿ tactical urbanism¿ such as the new post-pandemic Covid19 ¿ normality¿.Future research should link the methodology developed here with the ¿ Macroscopic Fundamental Diagram¿ of urban traffic (relationship between traffic flow and density at the zone level), it could include other positive environmental and social effects, improvements in the simulation model, and a systemization for the generation of ¿ packages¿ of street sections and their continuity at the zone / neighborhood level.Keywords: mobility management, redistribution of road space, Santiago de Cali, Pigou rate, tactical urban planning, traffic calming, sustainable mobility.

DOCTORAL DEGREE IN COMPUTER ARCHITECTURE

  • BELLVER BUENO, MÍRIAM: Image and video object segmentation in low supervision scenarios
    Author: BELLVER BUENO, MÍRIAM
    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: 07/01/2021
    Reading date: 26/03/2021
    Reading time: 09:30
    Reading place: Aula D5-010 FIB - UPC Campus Nord - Videoconferència: https://meet.google.com/nzz-haai-bta
    Thesis director: TORRES VIÑALS, JORDI | GIRÓ NIETO, XAVIER
    Committee:
         PRESIDENT: AKATA, ZEYNEP
         SECRETARI: MORENO NOGUER, FRANCESC D\'ASSIS
         VOCAL NO PRESENCIAL: KALANTIDIS, YANNIS
    Thesis abstract: Computer vision plays a key role in Artificial Intelligence because of the rich semantic information contained in pixels and the ubiquity of cameras nowadays. Multimedia content is on a rise since social networks have such a strong impact in our society and access to the internet becomes more widespread. This context allows the gathering of large datasets which have fostered great advancements in the computer vision field thanks to deep neural networks. These models can effectively exploit large amounts of data to reach a high expressive power. Since the breakout of Imagenet, a large dataset for image classification, most computer vision tasks have benefited from deep neural networks. Among the different tasks in the computer vision field, locating objects in images and videos is a central one, as it has many applications in autonomous driving, surveillance, image and video edition, medical diagnosis and biometrics along with others. Localization of objects can be obtained with bounding boxes around the target objects, or with accurate pixel-level masks that delineate the instances. The latter is a more challenging task, but fundamental for certain applications where edges of objects need to be determined. The main task addressed in this thesis is instance segmentation, that consists in, given an image or video, providing pixel-level masks for each instance of certain semantic object classes. In order to train a segmentation model, current solutions rely on large amounts of pixel-wise annotations, which demand significant human effort to collect. Furthermore, expert knowledge is needed to gather certain annotations, such as labels for medical images. In consequence, there is a huge interest for systems that work with less-demanding forms of supervision, such as weakly or semi-supervised pipelines.  Besides, in some segmentation tasks, human effort is not only needed for training the models, but also at inference. In semi-automatic systems, user input may be required as guidance to start the system. One example is the task of one-shot Video Object Segmentation~(osVOS), which expects that the end-user provides a pixel-level mask for each object to be tracked in the first frame of the video. Following, the model must predict the segmentation mask of the tracked objects for the remaining frames. These initialization cues are crucial for high accuracy, but they are arduous to obtain. An alternative are models that depend on weaker input signals that are user-friendlier.This thesis explores different supervision scenarios for the instance segmentation task, distinguishing between supervision during training and at inference, and focusing on low-supervision setups. In the first part of the thesis we present a novel recurrent architecture for video object segmentation that is end-to-end trainable in a fully-supervised setup, and that does not require any post-processing step, i.e., the output of the model directly solves the addressed task. The second part of the thesis aims at lowering the annotation cost, in terms of labeling time, needed to train image segmentation models. We explore semi-supervised pipelines and show results when a very limited budget is available. The third part of the dissertation attempts to alleviate the supervision required by semi-automatic systems at inference time. Particularly, we focus on semi-supervised video object segmentation, which typically requires generating a binary mask for each instance to be tracked. In contrast, we present a model for language-guided video object segmentation, which identifies the object to segment with a natural language expression. We study current benchmarks, propose a novel categorization of referring expressions for video, and identify the main challenges posed by the video task.

DOCTORAL DEGREE IN EARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS

  • MONTALBAN TURON, CARLOS: Análisis estructural de escaleras para edificios frente a viento y sismo
    Author: MONTALBAN TURON, 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 EARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS
    Department: (DECA)
    Mode: Normal
    Deposit date: 14/01/2021
    Reading date: pending
    Reading time: pending
    Reading place: pending
    Thesis director: BRUFAU NIUBÓ, ROBERTO | GONZALEZ DRIGO, JOSE RAMON
    Committee:
         PRESIDENT: MAÑA REIXACH, FRUCTUOSO
         SECRETARI: MARTÍN SÁIZ, RODRIGO
         VOCAL: DE SOUSA CRUZ, PAULO JORGE
    Thesis abstract: In this PhD Dissertation the structural performance of buildings with stairs submitted to lateral loads, is investigated. Because of the historical neglect of the interaction effects between the main structure and stairs, in professional and scientific practices, the objective is to address the current uncertainty regarding the structural safety of the evacuation exits of buildings, when they face seismic threats. For this reason, solutions are investigated in search of the optimal interaction between the main structure and the stairs. Currently, the project of buildings with stairs is controlled by different types of regulations, to ensure that, in an accidental situation, the stairs are the safest place and route to evacuate the building. However, in front of seismic threats, it is recommended not to stay in areas of the building with stairs, because it has been proven that they are elements highly vulnerable to the effects of the earthquake. The criteria for fire safety and against seismic threats are contradictory. Therefore, the need to rethink the way of designing stairs as well as their interaction with the building structure is confirmed. In an accidental situation (be it due to fire or to earthquake), the integrity of the staircase is essential to ensure a rapid evacuation of and adequate assistance to the users of the building and, for this reason, the structural safety of the evacuation routes should be guaranteed, in front of any accidental situation. In this research, four three dimensions (3D) models have been defined and, in each one of them, a non-linear static analysis has been performed against incremental pushes in the two main directions, which involves eight pushover analyses. Two analysis models correspond to the usual way of analyzing seismic behavior today, that is, without considering the structural presence of the stairs in the calculation model. The other two propose two different stair solutions, which, in these cases, have been modeled as part of the main structure. The research is carried out through three different fields of knowledge, the coordination of which has made it possible to solve a problem of international concern that each year causes the loss of hundreds of humans¿ lives, serious accidents and significant material damage, on all continents of the world. The three main areas of knowledge are: 1) architecture, 2) steel building engineer-ing, and 3) the study of seismic behavior (earthquake engineering). The contribution of this thesis to the problem of the fragility of the stairs could hardly have been made from the specialization in a single area of the three mentioned ones. Through the development, some preestablished impositions in each field of study are questioned and overcome: 1) the function of stairs in architecture, 2) the reason for the bracing system and the external actions that actually act on them and 3) the determining incidence of the stairs on the overall dynamic and seismic behavior of the building (structural dynamics and seis-mology). The main contribution is to offer, for the first time, an architecture project that provides a transversal solution to the three areas of study. Starting from Le Corbusier's definition, "... architecture is the wise, correct and magnificent game of volumes organized under light¿." Here, the parallelism could be nuanced: "... and of the organized masses in the face of acceleration". The scope of this thesis has been to design buildings in which the main structure and the stairs constitute an effective structural type against the effects of vertical (gravity) and horizontal (wind or earthquake) acceleration loads. The results obtained prove that the integration of the essential elements of the architecture (the main structure and the stairs, in this case) allows creating new, safer, more economical and resilient structural types.
  • SOSSA ARANCIBIA, VIVIANA ALEJANDRA: Inspección no destructiva de estructuras mediante georradar: análisis de daños por corrosión y por otras patologías
    Author: SOSSA ARANCIBIA, VIVIANA ALEJANDRA
    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 EARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS
    Department: (DECA)
    Mode: Normal
    Deposit date: 30/11/2020
    Reading date: 11/03/2021
    Reading time: 11:30
    Reading place: PhD thesis by videoconference. Escola Camins. https://meet.google.com/ckz-kgee-amp
    Thesis director: PEREZ GRACIA, MARIA DE LA VEGA | GONZALEZ DRIGO, JOSE RAMON
    Committee:
         PRESIDENT: GARCÍA GARCÍA, FRANCISCO
         SECRETARI: DI CAPUA, DANIEL
         VOCAL: SOLLA CARRACELA, MERCEDES
    Thesis abstract: This thesis aims to studythe capacities and limitations of Ground Penetrating Radar (GPR) to support inspection, assessment, maintenance and rehabilitation tasks, helping to earlydetection and evaluation ofpathologies in unreinforced masonryconstructions, as well as in reinforcing concrete structures.One ofthe most common pathologies in existing reinforced concrete structures is corrosion damage. In fact, this is a pathologythat, in more advanced stages, may comprom ise the integrity of sorne structural elements, or e\en of the whole structural system. Corros ion dam age reduces the effecti\e cross section of steel reinforcing bars , dim inishing the bond between reinforcement and concrete, and affecting, dueto physical and chemical processes, the concrete that inwl\es the corroded steel reinforcing bars. In reinforced concrete structures, the corrosion ofsteel reinforcing bars is, in general, hidden. Accordingly , remotely or at distance assessment techniques are desirable , which aims to assess the integrity of steel elements, generally inaccessible through direct contact.The implementation of non-destructi\e tests (NDT) is a com mon practice when analysing pathologies in historical buildings, where inter'A:lntions should be as minimal invasi\e as possible . Sorne ofthe mostcommon methods to assess corrosion, such as the potential of corrosion, the petrographic analysis and the resistivimeter, present sorne disadvantages in comparison to the GPR. In fact, the uses of such methods require a considerable time, they are slightty invasi\e, and its application is localized, which means thattheir application only co\ers a reduced area of analysi s.In orderto assess the GPR capacity for detecting corros ion dam age, different laboratory tests were respecti\ely de\eloped, being the obtained results extremely satisfactory. Accordingly, it is possible to identify the following achie\ements: (i) a fast data acquisition planning methodologywas well established; (ii) the key elements and parameters for corrosion detection, within a qualitati\e analysis, were respecti\elyidentified; (iii) the contoureffects, related to a change on geometry, were identified and duly controlled; and (iv) a numerical approximation method, based on energy attenuation of GPR, for assessing the presence and degree ofcorrosion in damaged samples, was proposed with success. Obtained results are themsel\es a strong contribution of de\eloped research studies for the state of art.Four in-field tests, implemented on existing structures were respecti\ely developed, aim ing to apply and validate the methodologies, results and conclusions, obtained from laboratory tests. Toree case studies are related to historical constructions, belonging to the cultural heritage of the city of Barcelona, in Spain. The obtained results from GPR, combined, in sorne cases, with boreholes and seism ic tomography, allowed to identify pathologies dueto hum idity, corrosion and differential setttements. A fourth case study, de\eloped on a contemporary structure, in reinforcing concrete, and only using GPR, allowed to identifyand localize pathologies dueto corrosion damage.The laboratorytests and the case studies, using GPR, combined or not with other techniques, showed a strong capacityto detect and assess early stage pathologies, especially dueto corrosion damage, through fast, non-invasi\e and non­ destructi\e prospections.This strategy has econom ical and social advan tages . lndeed, a fast detection of pathologies , allow the rehabilitation of existing structures with a minimum amount of budget, when comparing with the needed resources to face damage in a more se\ere stage. The assessment ofpathologies in earlystages with GPR, especiallywhen combined with other techniques, allow then to ensure more resilient structures, by increasing their reliability, safety, and availability, and by decreasing their operational costs.

DOCTORAL DEGREE IN ELECTRONIC ENGINEERING

  • AYMERICH GUBERN, JOAN: Low-Power Read-Out Ics for Smart Electrochemical Sensors
    Author: AYMERICH GUBERN, JOAN
    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: 01/12/2020
    Reading date: 18/03/2021
    Reading time: 10:00
    Reading place: Aula Teleensenyament Edifici B3 - UPC Campus Nord - Videoconferència: https://meet.google.com/psk-qkma-ctk
    Thesis director: SERRA GRAELLS, FRANCESC | DEI, MICHELE
    Committee:
         PRESIDENT: BALDI COLL, ANTONI
         SECRETARI: MOLL ECHETO, FRANCESC DE BORJA
         VOCAL: PANTELIS, GEORGIOU
    Thesis abstract: Electrochemical sensors are expanding rapidly over other chemical sensoring technologies because of their potential to generate precise, selective, miniaturized and cost-effective analytical devices. These features satisfy the emerging global demand for disposable testing systems at the point-of-need, where usability, portability, and price counts most, enabling to detect critical analytical evidence by anyone, any-where and at any time, without concerning about recalibration and limited shelf life. In particular a disposable electrochemical device must include a paired smart electronic interface to specifically bias the electrochemical cell, acquire signals, per-form data conversion and communicate measurements through a standard digital interface, all under severe restrictions of size and power consumption.This thesis describes the development of a novel, cost-effective, disposable, high-performance and user-friendly electrochemical sensing platform that combines the smartness of CMOS integrated circuits (ICs) with the flexibility of printed electronics.Two practical µW-range readout integrated circuit (ROIC) realizations in 65-nm and0.18-µmCMOS technologies are presented and specifically optimized for the potentiostatic biasing and amperometric read-out of electrochemical sensors. The proposed frontend architectures yield very elegant and compact CMOS implementations by reusing the dynamic properties of the sensor itself to implement continuous-time mixed electrochemical delta-sigma modulators (¿SM). The topologies include differential potentiostats to extend its range. Furthermore, low limit of detection (LOD) values can be achieved by implementing a novel cancellation mechanism of the flicker noise coming from the feedback DAC of the electrochemical ¿SM. A standard interface based onI2Cis included on-chip not only to control the extensive system configuration but also to limit the number of IC pads towards a low-cost flip-chip assembly on flexible substrates. Experimental results from both electrical and electrochemical tests are presented and compared to other state-of-the-art electrochemical sensor frontends.A cost-effective hybrid electronics interfacing approach is proposed, where the electrochemical sensor is directly printed on a flexible PEN substrate that also hosts the CMOS readout integrated circuit (ROIC) as a bare die without wire bonding. Low-cost inkjet printing technology is employed for the development of a three-electrode sensor and all the required connectivity. Anisotropic conductive adhesives are investigated as an emerging approach for mechanical and electrical contact between the IC die and printed inks in order to obtain a disposable flexible smart electrochemical sensory device.
  • SEGURA GARCIA, DANIEL: Development of silicon photonic structures for sensing and signal processing
    Author: SEGURA GARCIA, DANIEL
    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: Temporary seizure
    Deposit date: 19/11/2020
    Reading date: 19/03/2021
    Reading time: 11:00
    Reading place: Aula Teleensenyament B3 planta 1 - UPC Campus Nord - videoconferència: meet.google.com/cek-kqof-dnt
    Thesis director: RODRIGUEZ MARTINEZ, ANGEL
    Committee:
         PRESIDENT: MARSAL GARVI, LLUIS FRANCESC
         SECRETARI: PUIGDOLLERS GONZALEZ, JOAQUIN
         VOCAL: MORENO SERENO, MAURICIO
    Thesis abstract: Silicon photonics is the opportunity that one of the most amazing materials in nature, silicon, has offered once its electronic technological possibilities are reaching its limit. The transparency of this material in the near and mid infrared, along with the extensively developed manufacturing processes, opens the door to the miniaturisation of complex optical systems used in innumerable applications. Ultra-fast communications with low power consumption or highly selective and sensible sensors are some of the most promising ones. In this thesis the optical properties of silicon have been exploded from two differentiated perspectives: the study of macroporous silicon photonic crystals applied to selective gas detection, and the development of in-house fabrication process for integrated silicon photonic circuits. In the first part of the thesis, devoted to macroporous silicon photonic crystal, efforts have been focused on understanding the multiple sources of distortion of the optical response of the same as well as the improvement of some figures of merit such as bandgap width, quality factor or transmittance. The improvement of these figures of merit could lead to the obtaining of photonic structures with potential selective light filtering market applications, in our case, focused to spectroscopic gas detection.On the other hand, in the second part of the thesis, a prospective work on the development of a standardised in-house fabrication-simulation-measurement process has been performed. In our group, and as far as I now at UPC, there was no previous knowledge on the fabrication of these devices. Therefore, we have had to develop all the fabrication/measurement protocols and measurement tools. With these processes optimized, different resonating optical structures have been obtained with high quality factors and relatively low losses. This thesis opens the door to the in-house fabrication of more complex optical circuits, which can be used to many applications, such as integrated optical gas sensors or beam stirring of THz antennas.

DOCTORAL DEGREE IN ENVIRONMENTAL ENGINEERING

  • BENVENISTE PEREZ, GABRIELA: Análisis de Ciclo de Vida de sistemas innovadores de almacenamiento eléctrico en Li-azufre para vehiculos
    Author: BENVENISTE PEREZ, GABRIELA
    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: Normal
    Deposit date: 27/11/2020
    Reading date: 05/03/2021
    Reading time: 10:00
    Reading place: Escola de Camins - UPC Campus Nord - videocofnerència: meet.google.com/mtk-zbzs-gye
    Thesis director: AMANTE GARCIA, BEATRIZ | CORCHERO GARCIA, CRISTINA
    Committee:
         PRESIDENT: RUIZ AMADOR, DIEGO
         SECRETARI: ÁLVAREZ DEL CASTILLO, MARÍA DOLORES
         VOCAL NO PRESENCIAL: FERREIRA FERREIRA, VICTOR JOSE
    Thesis abstract: The continuous and expected increase of electrification in the transport sector, the so-called "electromobility" revolution, is one of the main drivers of progress in energy storage for vehicle propulsion.Today's electric vehicles (EVs) use lithium-ion (Li-ion) batteries due to their high energy density compared to other types of batteries. Current rechargeable lithium-ion (Li-ion) batteries for EVs are capable of storing around 180 Wh/kg of energy density at cell level and 120 Wh/kg at battery level, while the typical consumption of one kg of petrol produces 3350 Wh of useful work. There is still a factor of 19 between the energy delivered by a kilo of petrol and 1 kg of battery (for example, the autonomy of a car with a similar weight that is powered by batteries is 5-10 times less than with petrol). Therefore, if we want to reach, or even approach, the goal of a 500 km autonomy with battery powered vehicles in the short term, it is necessary to research new materials and battery configurations. In this respect, lithium-Sulphur (Li-S) batteries are the closest battery technology capable of meeting these expectations.Despite the fact that solutions exist at a technical level, or are in the process of being implemented, to overcome the technological barriers which electric energy storage presents for EVs, their implementation on our roads remains a challenge and is below the expectations setout. One of the reasons why this implementation is not satisfactory is the high cost of electric vehicles, mainly due to the high cost of batteries.New electric storage technologies such as Li-S batteries must therefore take into account not only the technical factor for their design, but also strategies to be able to reuse them in a second life in order to reduce their potential cost and thus help reduce the price of the EV paid by the end user. Furthermore, in addition to offering a suitable technological solution and presenting itself as an economically viable alternative, it is necessary to study the impact on the environment produced throughout the life cycle of Li-S batteries.For this reason, this doctoral thesis focuses on the environmental analysis of all the stages of the life cycle of these batteries, from the scaling of Li-S button cells produced in the laboratory to a 50 kWh battery. The methodology used to calculate the environmental impacts of the batteries is the Life Cycle Assessment (LCA) according to ISO 14040 and 14044:2006, which allows a quantitative evaluation of the environmental profile of the batteries for all the stages of their life cycle, emphasizing the most critical aspects that can be improved. In addition, the thesis has also dealt with issues related to the suitability of the batteries for use in second life, based on current experience with Li-ion batteries. To this end, on the one hand, ageing tests have been carried out on the cells to determine their behaviour and longevity. On the other hand, an economic evaluation has been made of the actions taken to dismantle a battery once its first life in the vehicle has ended, this being the first stage to prepare the battery for its second life in a secondary energy storage system.The results obtained from these analyses have served as a basis for establishing a framework for adding more information on the environmental performance of these batteries in Li-S. In addition, information has been provided in order to determine the feasibility of using this type of battery, not only in a first life in the electric vehicle, but also in its second life in a stationary application, and in this way to be able to follow the principles of the Circular Economy.

DOCTORAL DEGREE IN PHOTONICS

  • HÜMBELI, PATRICK: Machine Learning for Quantum Physics and Quantum Physics for Machine Learning
    Author: HÜMBELI, PATRICK
    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: 11/02/2021
    Reading date: pending
    Reading time: pending
    Reading place: pending
    Thesis director: ACÍN DAL MASCHIO, ANTONIO
    Committee:
         PRESIDENT: VAN NIEUWENBURG, EVERT
         SECRETARI: GRASS, TOBIAS DANIEL
         VOCAL: DUNJKO, VEDRAN
    Thesis abstract: Research at the intersection of machine learning (ML) and quan- tum physics is a recent growing field due to the enormous expec- tations and the success of both fields. ML is arguably one of the most promising technologies that has and will continue to dis- rupt many aspects of our lives. The way we do research is almost certainly no exception and ML, with its unprecedented ability to find hidden patterns in data, will be assisting future scientific discoveries. Quantum physics on the other side, even though it is sometimes not entirely intuitive, is one of the most successful physical theories and we are on the verge of adopting some quan- tum technologies in our daily life. Quantum many-body physics is a subfield of quantum physics where we study the collective behavior of particles or atoms and the emergence of phenomena that are due to this collective behavior, such as phases of matter. The study of phase transitions of these systems often requires some intuition of how we can quantify the order parameter of a phase. ML algorithms can imitate something similar to intu- ition by inferring knowledge from example data. They can, there- fore, discover patterns that are invisible to the human eye which makes them excellent candidates to study phase transitions. At the same time, quantum devices are known to be able to perform some computational task exponentially faster than classical com- puters and they are able to produce data patterns that are hard to simulate on classical computers. Therefore, there is the hope that ML algorithms run on quantum devices show an advantage over their classical analog. This thesis is devoted to study two different paths along the front lines of ML and quantum physics. On one side we study the use of neural networks (NN) to classify phases of mater in many-body quantum systems. On the other side, we study ML algorithms that run on quantum computers. The connection be- tween ML for quantum physics and quantum physics for ML in this thesis is an emerging subfield in ML, the interpretability of learning algorithms. A crucial ingredient in the study of phase transitions with NNs is a better understanding of the predictions of the NN, to eventually infer a model of the quantum system and interpretability can assist us in this endeavor. The interpretabil- ity method that we study analyzes the influence of the training points on a test prediction and it depends on the curvature of the NN loss landscape. This further inspired an in-depth study of the loss of quantum machine learning (QML) applications which we as well will discuss. In this thesis we give answers to the questions of how we can leverage NNs to classify phases of matter and we use a method that allows to do domain adaptation to transfer the learned "in- tuition" from systems without noise onto systems with noise. To map the phase diagram of quantum many-body systems in a fully unsupervised manner, we study a method known from anomaly detection that allows us to reduce the human input to a mini- mum. We will as well use interpretability methods to study NNs that are trained to distinguish phases of matter to understand if the NNs are learning something similar to an order parame- ter and if their way of learning can be made more accessible to humans. And finally, inspired by the interpretability of classical NNs, we develop tools to study the loss landscapes of variational quantum circuits to identify possible differences between classi- cal and quantum ML algorithms that might be leveraged for a quantum advantage.

DOCTORAL DEGREE IN POLYMERS AND BIOPOLYMERS

  • KERIDOU, INA: Study on Crystallinity, Properties and Degradability of Poly-4-hidroxybutyrate and Related Polyesters
    Author: KERIDOU, INA
    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: Temporary seizure
    Deposit date: 16/02/2021
    Reading date: pending
    Reading time: pending
    Reading place: pending
    Thesis director: PUIGGALI BELLALTA, JORGE | FRANCO GARCIA, MARIA LOURDES
    Committee:
         PRESIDENT: MEAURIO ARRATE, EMILIANO
         SECRETARI: FERNANDEZ FRANCOS, XAVIER
         VOCAL: REINA LOZANO, JOSE ANTONIO
    Thesis abstract: In the last decades, polymeric biomaterials, due to their advanced physical and mechanical properties, have been used in a vast variety of surgical and pharmaceutical applications. In this thesis, a study on crystallinity, properties, and degradability ofpoly-4-hydroxybutyrate (P4HB), commercially marketed as MonoMax® by B. Braun Surgical S.A.U. as an absorbable monofilament suture, and related polyesters is presented. ·Part of this work has been executed under the collaborative research project established between PSEP (Polímeros Sintéticos. Estructura y Propieda s) research group of Universitat Politécnica de Catalunya and B. Braun Surgical S.A.U. (Center of Excellence far Closur :Technologies) with the principal purpose of evolving ahd investigating polymeric systems with specific biomedical ápplications.This study covers different tapies related to P4HB such as (a) the physical, chemical, thermal and mechanical characterization;(b) the study of the crystallization kinetics; (c) the study of the degradation behavior of P4HB; and (d) the production of nanofibers by the electrospinning technique. Moreover, the work includes a study on blends of two different polyesters: PGA/PCL blends also produced employing the electrospinning technique and biphasic PLA/PA blends.Crystallization was studied under both isothermal and non-isothermal conditions using optical microscopy and differential scanning calorimetry. Furthermore, supplementary experiments performed in a synchrotron radiation facility provided us with further information about the lamellae morphology, crystal structure, and molecular orientation.Hydrolytic and enzymatic degradation of different matrices of P4HB was carried out in different buffered media. The hydrolytic degradation has been studied considerírig media of different pH values and temperatures. Enzymatic degradation has also been evatu ated at physiotogical conditions using two different lipases. The hydrolytic degradation mechanism differs from the enzymatic, where bulk degradation and a random éháin scission are characteristic of samples exposed to hydrolytic media, whereas surface erosion and successive removal of monomer units are charac!eristlc of samples exposed to enzymatic media. Far annealed fibers, small-angle X-ray diffraction studies revealed a supramolecular structure with two different types of !amellar stacks. The spherulitic morphology of the enzymatically degraded films was highlighted by the elimination of the amorphous regions.Nanofibers of PGA/PCL and P4HB were preparad using the electrospinning technique. The PGA/PCL nanofibers were also loaded with pharmacological drugs and Lised as a reinforcing agent of biodegradable polymer matrices. On the other hand, the biologicat performance of P4HB nanofibers was achieved with the incorporation of fibroblast growth factors. Far this purpose, wound healing assay for two different cell lines (e.g., epithelial and fibroblast) were studied.Finally, a study on the blends of PLA and Polyamide 6,1O was carried out to investigate the confinement effect of neighboring polymer domains on the phase separation and the structure and the influence of the disperse phase of polyamide in promotingPLA crystallization.

DOCTORAL DEGREE IN SIGNAL THEORY AND COMMUNICATIONS

  • GARCÍA PASTOR, DAVID: Nonlinear analysis of electro-acoustic frequency-selective devices for communications
    Author: GARCÍA PASTOR, 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 SIGNAL THEORY AND COMMUNICATIONS
    Department: Department of Signal Theory and Communications (TSC)
    Mode: Confidentiality
    Deposit date: 03/02/2021
    Reading date: 09/03/2021
    Reading time: 14:00
    Reading place: Aula Teleensenyament - B3 - ETSETB - Campus Nord - videoconferència: meet.google.com/frc-hbet-ydy
    Thesis director: MATEU MATEU, JORDI | COLLADO GOMEZ, JUAN CARLOS
    Committee:
         PRESIDENT: AIGNER, ROBERT
         SECRETARI: UBEDA FARRE, EDUARDO
         VOCAL NO PRESENCIAL: MIREA, TEONA
    Thesis abstract: Nowadays, mobile devices have become a key technology in our lives, making us become part of a connected world, in which millions of mobile handsets are sold every year. In order to satisfy the user demands, many mobile communication standards are working together in the same device (LTE-A, 5G-NR, IEEE Wireless LAN Standards, etc.). High data rates are demanded for different wireless services working on a very crowded frequency spectrum, where all the devices and systems need to operate at the same time without detrimental of mutual interference. Although this major objective has to be faced from different perspectives, such as new modulations and new networking protocols, the radio frequency (RF) and microwave components, forming the communication chain in a transceiver, play a significant role on the whole system performance. Passive devices, like filters, contribute to the signal degradation due to passive intermodulation (PIM). PIM can be generated by the lack of mismatch between metallic contacts, oxidation, or basically, by the inherent nonlinear material properties used on the fabrication of the devices. Although the impact of PIM is lower than the distortion introduced by active devices, for current wireless services and their demanding requirements, any type of nonlinear generation is certainly an issue.Acoustic wave (AW) devices have become a fundamental technology for portable handsets supporting current wireless communication networks. Bulk Acoustic Wave (BAW) has become the main technology nowadays for high frequency filters. This technology allows a high degree of miniaturization, easily making more than 40 filters per device, and also gives other advantages as low insertion losses and multiple frequency operation. Despite these major advantages, BAW resonators exhibit a nonlinear behavior, i.e., they may suffer of intermodulation and harmonic distortion, which might become a real bottle neck for the full expansion of the technology in the ever increasing stringent requirements.The aim of this thesis is focused on characterizing this nonlinear limitation, quite present in acoustic resonators, by defining the origin of different nonlinear manifestations in BAW resonators, and providing new nonlinear models to reduce the computational time required to simulate those undesired effects.The first part of this work explains the basic knowledge about acoustic propagation and piezoelectricity, presenting the linear and nonlinear constitutive equations, including the typical nonlinear manifestations appearing in those devices. Then, the typical circuit models for AW devices and, more specifically its applicability to BAW devices, is presented.The second part of this work is focused on the nonlinear analysis of BAW resonators, by measuring different nonlinear manifestation of 8 different BAW devices, identifying the origin of the nonlinear effects and demonstrating that this unique hypothesis is consistent with those manifestations for all the measured resonators.

DOCTORAL DEGREE IN STATISTICS AND OPERATIONS RESEARCH

  • MUÑOZ AGUIRRE, MANUEL: From RNA to histological images: linking the transcriptome with human phenotypes through statistical learning
    Author: MUÑOZ AGUIRRE, 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 STATISTICS AND OPERATIONS RESEARCH
    Department: Department of Statistics and Operations Research (EIO)
    Mode: Article-based thesis
    Deposit date: 03/02/2021
    Reading date: pending
    Reading time: pending
    Reading place: pending
    Thesis director: GUIGÓ SERRA, RODERIC | GRAFFELMAN, JAN
    Committee:
         PRESIDENT: VALENCIA HERRERA, ALFONSO
         SECRETARI: RADEVA, PETIA IVANOVA
         VOCAL NO PRESENCIAL: BUTTE, ATUL JANARDHAN
    Thesis abstract: Genomic datasets are fundamental to broaden our understanding of human biology in the context of health and disease. However, the high-dimensional nature of gene expression and other molecular traits poses a challenge when attempting to find associations of these data types with human phenotypes. To this end, this thesis relies on statistical learning tools to mitigate the curse of dimensionality and link the human transcriptome with phenotypes at different orders of complexity: from RNA, to computationally-inferred cell type enrichments, and finishing with histological images and their corresponding free-text descriptions. We make four specific contributions. First, we built computational models based on gene expression of post-mortem human tissues in order to derive estimates of post mortem interval. Second, we redefined the basic histological types of tissue classification based on five broad transcriptional programs which define major cell types: epithelial, endothelial, mesenchymal, neural, and blood. We generated computational estimates for the enrichment of these major cell types and validated them through the analysis of histological images and free-text pathology reports, finding that departures from normal cellular enrichment correlate with disease-associated histological phenotypes. Third, we characterized the landscape of human sex-differential gene expression, finding that effects are small but ubiquitous and tend to be tissue-specific, with some of these genes being involved in biological and molecular functions related to disease and clinical phenotypes. Fourth, we proposed an in-silico methodology to spatially deconvolute gene expression from matched sample pairs of whole slide histological images and bulk RNA-seq gene expression, with the goal of replicating the spatial transcriptomics experimental technology. Within this study, we also developed a software tool to effortlessly process whole slide histological images into tiles for machine learning applications.

Last update: 05/03/2021 06:04:22.