NFV orchestration in edge and fog scenarios

Mención Internacional en el título de doctorLas infraestructuras de red actuales soportan una variedad diversa de servicios como video bajo demanda, video conferencias, redes sociales, sistemas de educación, o servicios de almacenamiento de fotografías. Gran parte de la población mundial ha comenzado a utilizar estos servicios, y los utilizan diariamente. Proveedores de Cloud y operadores de infraestructuras de red albergan el tráfico de red generado por estos servicios, y sus tareas de gestión no solo implican realizar el enrutamiento del tráfico, sino también el procesado del tráfico de servicios de red. Tradicionalmente, el procesado del tráfico ha sido realizado mediante aplicaciones/ programas desplegados en servidores que estaban dedicados en exclusiva a tareas concretas como la inspección de paquetes. Sin embargo, en los últimos anos los servicios de red se han virtualizado y esto ha dado lugar al paradigma de virtualización de funciones de red (Network Function Virtualization (NFV) siguiendo las siglas en ingles), en el que las funciones de red de un servicio se ejecutan en contenedores o máquinas virtuales desacopladas de la infraestructura hardware. Como resultado, el procesado de tráfico se ha ido haciendo más flexible gracias al laxo acople del software y hardware, y a la posibilidad de compartir funciones de red típicas, como firewalls, entre los distintos servicios de red. NFV facilita la automatización de operaciones de red, ya que tareas como el escalado, o la migración son típicamente llevadas a cabo mediante un conjunto de comandos previamente definidos por la tecnología de virtualización pertinente, bien mediante contenedores o máquinas virtuales. De todos modos, sigue siendo necesario decidir el en rutamiento y procesado del tráfico de cada servicio de red. En otras palabras, que servidores tienen que encargarse del procesado del tráfico, y que enlaces de la red tienen que utilizarse para que las peticiones de los usuarios lleguen a los servidores finales, es decir, el conocido como embedding problem. Bajo el paraguas del paradigma NFV, a este problema se le conoce en inglés como Virtual Network Embedding (VNE), y esta tesis utiliza el termino “NFV orchestration algorithm” para referirse a los algoritmos que resuelven este problema. El problema del VNE es NP-hard, lo cual significa que que es imposible encontrar una solución optima en un tiempo polinómico, independientemente del tamaño de la red. Como consecuencia, la comunidad investigadora y de telecomunicaciones utilizan heurísticos que encuentran soluciones de manera más rápida que productos para la resolución de problemas de optimización. Tradicionalmente, los “NFV orchestration algorithms” han intentado minimizar los costes de despliegue derivados de las soluciones asociadas. Por ejemplo, estos algoritmos intentan no consumir el ancho de banda de la red, y usar rutas cortas para no utilizar tantos recursos. Además, una tendencia reciente ha llevado a la comunidad investigadora a utilizar algoritmos que minimizan el consumo energético de los servicios desplegados, bien mediante la elección de dispositivos con un consumo energético más eficiente, o mediante el apagado de dispositivos de red en desuso. Típicamente, las restricciones de los problemas de VNE se han resumido en un conjunto de restricciones asociadas al uso de recursos y consumo energético, y las soluciones se diferenciaban por la función objetivo utilizada. Pero eso era antes de la 5a generación de redes móviles (5G) se considerase en el problema de VNE. Con la aparición del 5G, nuevos servicios de red y casos de uso entraron en escena. Los estándares hablaban de comunicaciones ultra rápidas y fiables (Ultra-Reliable and Low Latency Communications (URLLC) usando las siglas en inglés) con latencias por debajo de unos pocos milisegundos y fiabilidades del 99.999%, una banda ancha mejorada (enhanced Mobile Broadband (eMBB) usando las siglas en inglés) con notorios incrementos en el flujo de datos, e incluso la consideración de comunicaciones masivas entre maquinas (Massive Machine-Type Communications (mMTC) usando las siglas en inglés) entre dispositivos IoT. Es más, paradigmas como edge y fog computing se incorporaron a la tecnología 5G, e introducían la idea de tener dispositivos de computo más cercanos al usuario final. Como resultado, el problema del VNE tenía que incorporar los nuevos requisitos como restricciones a tener en cuenta, y toda solución debía satisfacer bajas latencias, alta fiabilidad, y mayores tasas de transmisión. Esta tesis estudia el problema des VNE, y propone algunos heurísticos que lidian con las restricciones asociadas a servicios 5G en escenarios edge y fog, es decir, las soluciones propuestas se encargan de asignar funciones virtuales de red a servidores, y deciden el enrutamiento del trafico en las infraestructuras 5G con dispositivos edge y fog. Para evaluar el rendimiento de las soluciones propuestas, esta tesis estudia en primer lugar la generación de grafos que representan redes 5G. Los mecanismos propuestos para la generación de grafos sirven para representar distintos escenarios 5G. En particular, escenarios de federación en los que varios dominios comparten recursos entre ellos. Los grafos generados también representan servidores en el edge, así como dispositivos fog con una batería limitada. Además, estos grafos tienen en cuenta los requisitos de estándares, y la demanda que se espera en las redes 5G. La generación de grafos propuesta sirve para representar escenarios federación en los que varios dominios comparten recursos entre ellos, y redes 5G con servidores edge, así como dispositivos fog estáticos o móviles con una batería limitada. Los grafos generados para infraestructuras 5G tienen en cuenta los requisitos de estándares, y la demanda de red que se espera en las redes 5G. Además, los grafos son diferentes en función de la densidad de población, y el área de estudio, es decir, si es una zona industrial, una autopista, o una zona urbana. Tras detallar la generación de grafos que representan redes 5G, esta tesis propone algoritmos de orquestación NFV para resolver con el problema del VNE. Primero, se centra en escenarios federados en los que los servicios de red se tienen que asignar no solo a la infraestructura de un dominio, sino a los recursos compartidos en la federación de dominios. Dos problemas diferentes han sido estudiados, uno es el problema del VNE propiamente dicho sobre una infraestructura federada, y el otro es la delegación de servicios de red. Es decir, si un servicio de red se debe desplegar localmente en un dominio, o en los recursos compartidos por la federación de dominios; a sabiendas de que el último caso supone el pago de cuotas por parte del dominio local a cambio del despliegue del servicio de red. En segundo lugar, esta tesis propone OKpi, un algoritmo de orquestación NFV para conseguir la calidad de servicio de las distintas slices de las redes 5G. Conceptualmente, el slicing consiste en partir la red de modo que cada servicio de red sea tratado de modo diferente dependiendo del trozo al que pertenezca. Por ejemplo, una slice de eHealth reservara los recursos de red necesarios para conseguir bajas latencias en servicios como operaciones quirúrgicas realizadas de manera remota. Cada trozo (slice) está destinado a unos servicios específicos con unos requisitos muy concretos, como alta fiabilidad, restricciones de localización, o latencias de un milisegundo. OKpi es un algoritmo de orquestación NFV que consigue satisfacer los requisitos de servicios de red en los distintos trozos, o slices de la red. Tras presentar OKpi, la tesis resuelve el problema del VNE en redes 5G con dispositivos fog estáticos y móviles. El algoritmo de orquestación NFV presentado tiene en cuenta las limitaciones de recursos de computo de los dispositivos fog, además de los problemas de falta de cobertura derivados de la movilidad de los dispositivos. Para concluir, esta tesis estudia el escalado de servicios vehiculares Vehicle-to-Network (V2N), que requieren de bajas latencias para servicios como la prevención de choques, avisos de posibles riesgos, y conducción remota. Para estos servicios, los atascos y congestiones en la carretera pueden causar el incumplimiento de los requisitos de latencia. Por tanto, es necesario anticiparse a esas circunstancias usando técnicas de series temporales que permiten saber el tráfico inminente en los siguientes minutos u horas, para así poder escalar el servicio V2N adecuadamente.Current network infrastructures handle a diverse range of network services such as video on demand services, video-conferences, social networks, educational systems, or photo storage services. These services have been embraced by a significant amount of the world population, and are used on a daily basis. Cloud providers and Network operators’ infrastructures accommodate the traffic rates that the aforementioned services generate, and their management tasks do not only involve the traffic steering, but also the processing of the network services’ traffic. Traditionally, the traffic processing has been assessed via applications/programs deployed on servers that were exclusively dedicated to a specific task as packet inspection. However, in recent years network services have stated to be virtualized and this has led to the Network Function Virtualization (Network Function Virtualization (NFV)) paradigm, in which the network functions of a service run on containers or virtual machines that are decoupled from the hardware infrastructure. As a result, the traffic processing has become more flexible because of the loose coupling between software and hardware, and the possibility of sharing common network functions, as firewalls, across multiple network services. NFV eases the automation of network operations, since scaling and migrations tasks are typically performed by a set of commands predefined by the virtualization technology, either containers or virtual machines. However, it is still necessary to decide the traffic steering and processing of every network service. In other words, which servers will hold the traffic processing, and which are the network links to be traversed so the users’ requests reach the final servers, i.e., the network embedding problem. Under the umbrella of NFV, this problem is known as Virtual Network Embedding (VNE), and this thesis refers as “NFV orchestration algorithms” to those algorithms solving such a problem. The VNE problem is a NP-hard, meaning that it is impossible to find optimal solutions in polynomial time, no matter the network size. As a consequence, the research and telecommunications community rely on heuristics that find solutions quicker than a commodity optimization solver. Traditionally, NFV orchestration algorithms have tried to minimize the deployment costs derived from their solutions. For example, they try to not exhaust the network bandwidth, and use short paths to use less network resources. Additionally, a recent tendency led the research community towards algorithms that minimize the energy consumption of the deployed services, either by selecting more energy efficient devices or by turning off those network devices that remained unused. VNE problem constraints were typically summarized in a set of resources/energy constraints, and the solutions differed on which objectives functions were aimed for. But that was before 5th generation of mobile networks (5G) were considered in the VNE problem. With the appearance of 5G, new network services and use cases started to emerge. The standards talked about Ultra Reliable Low Latency Communication (Ultra-Reliable and Low Latency Communications (URLLC)) with latencies below few milliseconds and 99.999% reliability, an enhanced mobile broadband (enhanced Mobile Broadband (eMBB)) with significant data rate increases, and even the consideration of massive machine-type communications (Massive Machine-Type Communications (mMTC)) among Internet of Things (IoT) devices. Moreover, paradigms such as edge and fog computing blended with the 5G technology to introduce the idea of having computing devices closer to the end users. As a result, the VNE problem had to incorporate the new requirements as constraints to be taken into account, and every solution should either satisfy low latencies, high reliability, or larger data rates. This thesis studies the VNE problem, and proposes some heuristics tackling the constraints related to 5G services in Edge and fog scenarios, that is, the proposed solutions assess the assignment of Virtual Network Functions to resources, and the traffic steering across 5G infrastructures that have Edge and Fog devices. To evaluate the performance of the proposed solutions, the thesis studies first the generation of graphs that represent 5G networks. The proposed mechanisms to generate graphs serve to represent diverse 5G scenarios. In particular federation scenarios in which several domains share resources among themselves. The generated graphs also represent edge servers, so as fog devices with limited battery capacity. Additionally, these graphs take into account the standard requirements, and the expected demand for 5G networks. Moreover, the graphs differ depending on the density of population, and the area of study, i.e., whether it is an industrial area, a highway, or an urban area. After detailing the generation of graphs representing the 5G networks, this thesis proposes several NFV orchestration algorithms to tackle the VNE problem. First, it focuses on federation scenarios in which network services should be assigned not only to a single domain infrastructure, but also to the shared resources of the federation of domains. Two different problems are studied, one being the VNE itself over a federated infrastructure, and the other the delegation of network services. That is, whether a network service should be deployed in a local domain, or in the pool of resources of the federation domain; knowing that the latter charges the local domain for hosting the network service. Second, the thesis proposes OKpi, a NFV orchestration algorithm to meet 5G network slices quality of service. Conceptually, network slicing consists in splitting the network so network services are treated differently based on the slice they belong to. For example, an eHealth network slice will allocate the network resources necessary to meet low latencies for network services such as remote surgery. Each network slice is devoted to specific services with very concrete requirements, as high reliability, location constraints, or 1ms latencies. OKpi is a NFV orchestration algorithm that meets the network service requirements among different slices. It is based on a multi-constrained shortest path heuristic, and its solutions satisfy latency, reliability, and location constraints. After presenting OKpi, the thesis tackles the VNE problem in 5G networks with static/moving fog devices. The presented NFV orchestration algorithm takes into account the limited computing resources of fog devices, as well as the out-of-coverage problems derived from the devices’ mobility. To conclude, this thesis studies the scaling of Vehicle-to-Network (V2N) services, which require low latencies for network services as collision avoidance, hazard warning, and remote driving. For these services, the presence of traffic jams, or high vehicular traffic congestion lead to the violation of latency requirements. Hence, it is necessary to anticipate to such circumstances by using time-series techniques that allow to derive the incoming vehicular traffic flow in the next minutes or hours, so as to scale the V2N service accordingly.The 5G Exchange (5GEx) project (2015-2018) was an EU-funded project (H2020-ICT-2014-2 grant agreement 671636). The 5G-TRANSFORMER project (2017-2019) is an EU-funded project (H2020-ICT-2016-2 grant agreement 761536). The 5G-CORAL project (2017-2019) is an EU-Taiwan project (H2020-ICT-2016-2 grant agreement 761586).Programa de Doctorado en Ingeniería Telemática por la Universidad Carlos III de MadridPresidente: Ioannis Stavrakakis.- Secretario: Pablo Serrano Yáñez-Mingot.- Vocal: Paul Horatiu Patra

Main Variables Affecting a Chemical-Enzymatic Method to Obtain Protein and Amino Acids from Resistant Microalgae

he development of microalgae uses requires further investigation in cell disruption alternatives to reduce the costs associated to this processing stage. This study aimed to evaluate the main variables affecting an extraction method to obtain protein and amino acids from microalgae. The method was based on a sequential alkaline-enzymatic process, with separate extractions and noncontrolled pH, and was applied to fresh biomass of a resistant species. The processed microalgae were composed of a consortium with Nannochloropsis sp. as predominant species. After the optimization of the pH of the alkaline reaction, the effect of the time of the alkaline reaction (30-120min), the time (30-120min) and temperature (40-60 degrees C) of the enzymatic reaction, and the biomass concentration (50-150mgml(-1)), on the extraction yields of protein and free amino nitrogen (FAN) and on the final concentration of protein in the extract, was studied using a response surface methodology. Even though all the variables and some interactions among them had a significant effect, the biomass concentration was the most important factor affecting the overall process. The results showed relevant information about the different options in order to maximize not only the response variables individually but also different combinations of them. Assays with optimized values reached maximum yields of 80.3% and 1.07% of protein (% of total protein) and FAN (% of total biomass), respectively, and a protein concentration in the extract of 15.2mgml(-1). The study provided the essential information of an alternative approach to obtain protein and amino acids from fresh biomass of resistant microalgae with a high yield, also opening perspectives for further research in particular aspects

Method to guide the design of project based learning activities based on educational theories

Project Based Learning (PjBL) has shown to be effective in engineering to acquire both professional and lifelong learning skills. Nevertheless, some authors assert it is not an easy instructional method to implement. It requires teaching skills and entails some difficulties for both students and teachers, specially related to the time and effort needed to put it into practice. In some countries, the implementation of PjBL has a limited scope, restricted to single courses that do not have a great repercussion in the curriculum. Moreover, some teachers tend to implement PjBL intuitively, based on their teaching experience instead of following important PjBL principies or instructional practices. To facilítate the proliferation and better establishment of PjBL in these countries, it is necessary to engage more teachers in best practices of this methodology, applying its main instructional principies and adequate educational theories. In this way, they could overeóme the difficulties mentioned above and obtain better results in their experiences. This study is aimed at defining a method to design activities based on PjBL. This method guides teachers in the use of PjBL principies and several instructional design models. In particular, the method deals with the definition and articulation of an appropriate problem. In addition, it faces three fundamental issues in active learning and especially in PjBL: Students' Motivation, Supporting Students' Work and Autonomous Working. This proposal is specially focused on those academic contexts in which instructors are starting to use this methodology and students are not used to dealing with ill-structured projeets, and consequently they could find important difficulties in its implementation. The method has been put into practice in three courses, where first results seem to be satisfactory according to a survey conducted by the Universidad Politécnica de Madrid. Results spanning the last six years of this survey have been analyzed. Currently, it is being used to implement a multidisciplinary project which covers four courses in a Master's degree. Finally, a collaborative online tool and teacher workshop further supports this method

Measuring the influence of Cooperative Learning and Project Based Learning on problem solvin skill.

The aim of this study is to evaluate the effects obtained after applying two active learning methodologies (cooperative learning and project based learning) to the achievement of the competence problem solving. This study was carried out at the Technical University of Madrid, where these methodologies were applied to two Operating Systems courses. The first hypothesis tested was whether the implementation of active learning methodologies favours the achievement of ?problem solving?. The second hypothesis was focused on testing if students with higher rates in problem solving competence obtain better results in their academic performance. The results indicated that active learning methodologies do not produce any significant change in the generic competence ?problem solving? during the period analysed. Concerning this, we consider that students should work with these methodologies for a longer period, besides having a specific training. Nevertheless, a close correlation between problem solving self appraisal and academic performance has been detected

Integration of three instructional design models within the organization of PBL activities

This work is aimed at defining a method to design courses based on Project Based Learning methodology. This proposal is specially focused on those academic contexts in which instructors are starting to use this methodology and students are not used to dealing with illstructured projects, and consequently they could find important difficulties in its implementation. To reach this goal, this method is based on several instructional design models, learning theories and PBL principles. In particular, the method faces three fundamental issues in active learning and especially in PBL: Students’ Motivation, Supporting Students’ Work and Autonomous Working. Engaging instructors to follow these models when they are designing the course facilitates the subsequent success during the course implementation. The method has been put into practice in three courses, where first results seem to be satisfactory according to a survey conducted by the University. Results of this survey over for the last six years have been analysed. Besides the description of the method, we present a collaborative online tool that supports i

Multi-domain VNF mapping algorithms

5G technologies are taking benefit of the Network Function Virtualization to achieve more flexible deployments. This new paradigm allows the resource sharing between operators in federated environments thanks to the decomposition of services into virtual network functions connected together composing a "service function chain". This work proposes algorithms to solve the placement of such chains in federated multi-domain scenarios satisfying imposed restrictions in terms of resource sharing. Algorithms run on top of an implemented simulator for federated scenarios where multiple operators are involved. Two of our proposed solutions reach O(N) running times in certain scenarios. Our results also show that we achieve acceptance ratios very similar to those obtained using a tabu meta-heuristic implementation.This work has been partially supported by the EU H2020 5G Exchange (5GEx) innovation project (grant no. 671636) and by EU H2020 5G-Transformer Project (grant no. 761536)

Análisis y procesado de señales multidimensionales para detección de eventos en condiciones desfavorables

Este trabajo trata la detección de irregularidades en un proceso de control de calidad de componentes de un reactor nuclear. Dichos procesos tienen como objetivo determinar si una componente está o no fuera de especificación. En el proceso de control de calidad se toman múltiples mediciones que llevan asociadas distintas señales, y de todas ellas existe una que refleja mejor que el resto las irregularidades, dicha señal es la que mide la densidad de las componentes. Sin embargo la señal de densidad tiene un problema, y es que lleva asociado un ruido que interfiere en el algoritmo existente para la detección de picos asociados con las irregularidades de las componentes del reactor. El modelo de ruido en las señales se corresponde con un modelo aditivo, donde la señal asociada al ruido aparece sumada a la señal original en todo momento, y debido a que no se conoce la caracterización de dicho ruido, las labores de eliminación de ruido no se pueden atener a ningún tipo de conocimiento sobre este. Para reducir el ruido en las señales de densidad, se ha hecho uso de filtros de Chebyshev y de la sustracción espectral (método ideado originalmente para la limpieza de ruido en señales de voz). Entre estos dos métodos, el último es con el que se han obtenido mejores resultados, pues consigue mejorar sustancialmente la presencia de señal frente al ruido, así como la detección de los picos existentes en las señales. Todo esto requiere de cierto conocimiento del mundo del tratamiento de señales, por ello se comienza exponiendo la serie de Fourier y su convergencia, y cómo de ella se deriva la transformada de Fourier. Así mismo también se explica cómo interpretar el dominio frecuencial que se obtiene con la transformada de Fourier, y cómo obtener su versión discreta.This paper deals with the detection of irregularities in the process of quality control of components of a nuclear reactor. These processes aim to determine whether a component is or is not out of specification. In the quality control process multiple measurements are taken, each measure has an associated signals, and among them there is one that reflects the irregularities better than the rest, that signal is the one measuring the density of the components. However the density signal has a problem, and it’s that it has an associated noise that interferes with the existing algorithm for detecting peaks associated with irregularities of the reactor components. The noise model in the signals corresponds to an additive model, where the signal associated with noise appears added to the original signal at all times, and because the noise characterization is not known, the work removal noise can not stick to any knowledge about this. To reduce noise in density signals, Chebyshev filters and spectral subtraction have been used (the last one was originally designed for cleaning noise in voice signals). Between these two methods, the latter is the one that have given better results, as it improves substantially the presence of signal above noise, as well as the detection of existing peaks in the signals. All this requires some knowledge of the world of signal processing, therefore the paper begins by exposing the Fourier series and their convergence, and how the Fourier transform is derived. Likewise, it also explains how to interpret the frequency domain obtained with the Fourier transform, and how to get it’s discrete version

Efecto y especificidad de un derivado de la metionina-encefalina (FK-33-824) sobre la secreción de las hormonas hipofisarias

Tesis - Universidad Complutense de Madrid, 1981.Depto. de Bioquímica y Biología MolecularFac. de Ciencias QuímicasTRUEProQuestpu

A network perspective on antimicrobial peptide combination therapies: the potential of colistin, polymyxin B and nisin

Supplementary data associated with this article can be found, in the online version, at doi:10.1016/j.ijantimicag.2017.02.012.Antimicrobial combinations involving antimicrobial peptides (AMPs) attract considerable attention within current antimicrobial and anti-resistance research. The objective of this study was to review the available scientific literature on the effects of antimicrobial combinations involving colistin (polymyxin E), polymyxin B and nisin, which are US Food and Drug Administration (FDA)-approved AMPs broadly tested against prominent multidrug-resistant pathogens. A bioinformatics approach based on literature mining and manual expert curation supported the reconstruction of experimental evidence on the potential of these AMP combinations, as described in the literature. Network analysis enabled further characterisation of the retrieved antimicrobial agents, targets and combinatory effects. This systematic analysis was able to output valuable information on the studies conducted on colistin, polymyxin B and nisin combinations. The reconstructed networks enable the traversal and browsing of a large number of agent combinations, providing comprehensive details on the organisms, modes of growth and methodologies used in the studies. Therefore, network analysis enables a bird's-eye view of current research trends as well as in-depth analysis of specific drugs, organisms and combinatory effects, according to particular user interests. The reconstructed knowledge networks are publicly accessible at http://sing-group.org/antimicrobialCombination/. Hopefully, this resource will help researchers to look into antimicrobial combinations more easily and systematically. User-customised queries may help to identify missing and less studied links and to generate new research hypotheses.This work was supported by the Portuguese Foundation for Science and Technology(FCT)under the scope of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 [POCI01-0145-FEDER-006684] and BioTecNorte operation [NORTE-010145-FEDER-000004], funded by the European Regional Development Fund under the scope of Norte2020—Programa Operacional Regional do Norte.The authors also acknowledge the support received from FCT and the European Community fund FEDER, through Program COMPETE, under the scope of the Project RECI/BBB-EBI/0179/2012 [FCOMP-01-0124-FEDER-027462],the[14VI05]Contract-Programme from the University of Vigo (Vigo, Spain), the INOU-16-05 project from the Provincial Council of Ourense, and the Agrupamento INBIOMED from DXPCTSUG-FEDER unha maneira de facer Europa [2012/273]. SING group thanks CITI (Centro de Investigación, Transferencia e Innovación) from University of Vigo for hosting its IT infrastructure. Finally, the authors acknowledge the PhD grant of Paula Jorge[Grant no. SFRH/BD/88192/2012],funded by FCT,thePhD grants of Martín Pérez-Pérez and Gael Pérez-Rodríguez, funded by the Xunta de Galicia and the University of Vigo, and the Research grant 2014 of Anália Lourenço by the European Society of Clinical Microbiology and Infectious Diseases (ESCMID).info:eu-repo/semantics/publishedVersio

Resolución de Problemas Inversos en Mecánica de Sólidos con aplicación al modelado e identificación de propiedades mecánicas de tejidos biológicos

Los problemas de modelado e identificación de propiedades mecánicas consisten en buscar reproducir un comportamiento constitutivo observado, a través de la identificación de parámetros de un modelo dado. Dada la importancia de sus aplicaciones, el planteo y resolución de estos problemas en el estudio de tejidos biológicos ha generado gran interés en diversas comunidades científicas en las últimas décadas. En esta tesis se desarrollan nuevas herramientas para la resolución de problemas inversos asociados al modelado del comportamiento mecánico de tejidos biológicos. Se presentan tres nuevas formulaciones de optimización convexa del problema de identificación no homogénea de material elástico lineal. Se desarrolla también una metodología para incluir una técnica de regularización, junto con una estrategia para la elección del parámetro de regularización. Se resuelven seis ejemplos numéricos para validar y comparar las formulaciones propuestas. Analizando los resultados se concluye que las mismas son más eficientes que las presentes en la literatura, así como también apropiadas para su aplicación a datos con errores. Se presenta también un nuevo modelo viscoelástico fraccional para el modelado del comportamiento constitutivo del tejido arterial. Se desarrolla un método de caracterización, el cual es aplicado a la resolución de tres ejemplos numéricos con datos artificiales, comprobando su efectividad. Al aplicar el método a datos obtenidos experimentalmente de presión y diámetro de arterias, se muestran las ventajas del nuevo modelo y su factibilidad para ser aplicado a datos obtenidos de forma no invasiva. Se concluye que tanto las formulaciones propuestas para el Problema de Identificación como el nuevo modelo viscoelástico fraccional constituyen aportes a la resolución de problemas inversos asociados al modelado de tejidos biológicos. Se presentan recomendaciones sobre posibles cambios en procedimientos de obtención de datos de presión y diámetro en humanos. También se presentan trabajos futuros a desarrollar para concretar a corto plazo la aplicación a datos obtenidos in-vivo