An Improved Simulated Annealing Technique for Enhanced Mobility in Smart Cities

Vehicular traffic congestion is a significant problem that arises in many cities. This is due to the increasing number of vehicles that are driving on city roads of limited capacity. The vehicular congestion significantly impacts travel distance, travel time, fuel consumption and air pollution. Avoidance of traffic congestion and providing drivers with optimal paths are not trivial tasks. The key contribution of this work consists of the developed approach for dynamic calculation of optimal traffic routes. Two attributes (the average travel speed of the traffic and the roads’ length) are utilized by the proposed method to find the optimal paths. The average travel speed values can be obtained from the sensors deployed in smart cities and communicated to vehicles via the Internet of Vehicles and roadside communication units. The performance of the proposed algorithm is compared to three other algorithms: the simulated annealing weighted sum, the simulated annealing technique for order preference by similarity to the ideal solution and the Dijkstra algorithm. The weighted sum and technique for order preference by similarity to the ideal solution methods are used to formulate different attributes in the simulated annealing cost function. According to the Sheffield scenario, simulation results show that the improved simulated annealing technique for order preference by similarity to the ideal solution method improves the traffic performance in the presence of congestion by an overall average of 19.22% in terms of travel time, fuel consumption and CO2 emissions as compared to other algorithms; also, similar performance patterns were achieved for the Birmingham test scenario

Applications of ontology in the internet of things: A systematic analysis

Ontology has been increasingly implemented to facilitate the Internet of Things (IoT) activities, such as tracking and information discovery, storage, information exchange, and object addressing. However, a complete understanding of using ontology in the IoT mechanism remains lacking. The main goal of this research is to recognize the use of ontology in the IoT process and investigate the services of ontology in IoT activities. A systematic literature review (SLR) is conducted using predefined protocols to analyze the literature about the usage of ontologies in IoT. The following conclusions are obtained from the SLR. (1) Primary studies (i.e., selected 115 articles) have addressed the need to use ontologies in IoT for industries and the academe, especially to minimize interoperability and integration of IoT devices. (2) About 31.30% of extant literature discussed ontology development concerning the IoT interoperability issue, while IoT privacy and integration issues are partially discussed in the literature. (3) IoT styles of modeling ontologies are diverse, whereas 35.65% of total studies adopted the OWL style. (4) The 32 articles (i.e., 27.83% of the total studies) reused IoT ontologies to handle diverse IoT methodologies. (5) A total of 45 IoT ontologies are well acknowledged, but the IoT community has widely utilized none. An in-depth analysis of different IoT ontologies suggests that the existing ontologies are beneficial in designing new IoT ontology or achieving three main requirements of the IoT field: interoperability, integration, and privacy. This SLR is finalized by identifying numerous validity threats and future directions

Robust and cheating-resilient power auctioning on Resource Constrained Smart Micro-Grids

The principle of Continuous Double Auctioning (CDA) is known to provide an efficient way of matching supply and demand among distributed selfish participants with limited information. However, the literature indicates that the classic CDA algorithms developed for grid-like applications are centralised and insensitive to the processing resources capacity, which poses a hindrance for their application on resource constrained, smart micro-grids (RCSMG). A RCSMG loosely describes a micro-grid with distributed generators and demand controlled by selfish participants with limited information, power storage capacity and low literacy, communicate over an unreliable infrastructure burdened by limited bandwidth and low computational power of devices. In this thesis, we design and evaluate a CDA algorithm for power allocation in a RCSMG. Specifically, we offer the following contributions towards power auctioning on RCSMGs. First, we extend the original CDA scheme to enable decentralised auctioning. We do this by integrating a token-based, mutual-exclusion (MUTEX) distributive primitive, that ensures the CDA operates at a reasonably efficient time and message complexity of O(N) and O(logN) respectively, per critical section invocation (auction market execution). Our CDA algorithm scales better and avoids the single point of failure problem associated with centralised CDAs (which could be used to adversarially provoke a break-down of the grid marketing mechanism). In addition, the decentralised approach in our algorithm can help eliminate privacy and security concerns associated with centralised CDAs. Second, to handle CDA performance issues due to malfunctioning devices on an unreliable network (such as a lossy network), we extend our proposed CDA scheme to ensure robustness to failure. Using node redundancy, we modify the MUTEX protocol supporting our CDA algorithm to handle fail-stop and some Byzantine type faults of sites. This yields a time complexity of O(N), where N is number of cluster-head nodes; and message complexity of O((logN)+W) time, where W is the number of check-pointing messages. These results indicate that it is possible to add fault tolerance to a decentralised CDA, which guarantees continued participation in the auction while retaining reasonable performance overheads. In addition, we propose a decentralised consumption scheduling scheme that complements the auctioning scheme in guaranteeing successful power allocation within the RCSMG. Third, since grid participants are self-interested we must consider the issue of power theft that is provoked when participants cheat. We propose threat models centred on cheating attacks aimed at foiling the extended CDA scheme. More specifically, we focus on the Victim Strategy Downgrade; Collusion by Dynamic Strategy Change, Profiling with Market Prediction; and Strategy Manipulation cheating attacks, which are carried out by internal adversaries (auction participants). Internal adversaries are participants who want to get more benefits but have no interest in provoking a breakdown of the grid. However, their behaviour is dangerous because it could result in a breakdown of the grid. Fourth, to mitigate these cheating attacks, we propose an exception handling (EH) scheme, where sentinel agents use allocative efficiency and message overheads to detect and mitigate cheating forms. Sentinel agents are tasked to monitor trading agents to detect cheating and reprimand the misbehaving participant. Overall, message complexity expected in light demand is O(nLogN). The detection and resolution algorithm is expected to run in linear time complexity O(M). Overall, the main aim of our study is achieved by designing a resilient and cheating-free CDA algorithm that is scalable and performs well on resource constrained micro-grids. With the growing popularity of the CDA and its resource allocation applications, specifically to low resourced micro-grids, this thesis highlights further avenues for future research. First, we intend to extend the decentralised CDA algorithm to allow for participants’ mobile phones to connect (reconnect) at different shared smart meters. Such mobility should guarantee the desired CDA properties, the reliability and adequate security. Secondly, we seek to develop a simulation of the decentralised CDA based on the formal proofs presented in this thesis. Such a simulation platform can be used for future studies that involve decentralised CDAs. Third, we seek to find an optimal and efficient way in which the decentralised CDA and the scheduling algorithm can be integrated and deployed in a low resourced, smart micro-grid. Such an integration is important for system developers interested in exploiting the benefits of the two schemes while maintaining system efficiency. Forth, we aim to improve on the cheating detection and mitigation mechanism by developing an intrusion tolerance protocol. Such a scheme will allow continued auctioning in the presence of cheating attacks while incurring low performance overheads for applicability in a RCSMG

A Communications-Oriented Perspective on Traffic Management Systems for Smart Cities: Challenges and Innovative Approaches

The growing size of cities and increasing population mobility have determined a rapid increase in the number of vehicles on the roads, which has resulted in many challenges for road traffic management authorities in relation to traffic congestion, accidents, and air pollution. Over the recent years, researchers from both industry and academia have been focusing their efforts on exploiting the advances in sensing, communication, and dynamic adaptive technologies to make the existing road traffic management systems (TMSs) more efficient to cope with the aforementioned issues in future smart cities. However, these efforts are still insufficient to build a reliable and secure TMS that can handle the foreseeable rise of population and vehicles in smart cities. In this survey, we present an up-to-date review of the different technologies used in the different phases involved in a TMS and discuss the potential use of smart cars and social media to enable fast and more accurate traffic congestion detection and mitigation. We also provide a thorough study of the security threats that may jeopardize the efficiency of the TMS and endanger drivers' lives. Furthermore, the most significant and recent European and worldwide projects dealing with traffic congestion issues are briefly discussed to highlight their contribution to the advancement of smart transportation. Finally, we discuss some open challenges and present our own vision to develop robust TMSs for future smart cities

Aportaciones a la monitorización y predicción del recurso solar para la integración de fuentes renovables en sistemas eléctricos basadas en internet de las cosas

[SPA] Esta tesis doctoral se presenta bajo la modalidad de compendio de publicaciones. La necesidad de lograr una economía descarbonizada para evitar los efectos del cambio climático ha derivado en una serie de compromisos internacionales que obligan a España y Europa a reducir paulatinamente sus emisiones de gases de efecto invernadero hasta alcanzar la neutralidad climática en 2050. Este objetivo solo se puede alcanzar con un nuevo modelo energético basado en una integración masiva de energías renovables. Entre las tecnologías llamadas a convertirse en uno de los pilares de esta descarbonización de la economía se encuentra la energía solar fotovoltaica como consecuencia de su propia madurez tecnológica y la significativa reducción de costes que ha experimentado en los últimos años. Dentro de las instalaciones fotovoltaicas, una de las tipologías que ha recibido un mayor impulso son las instalaciones de autoconsumo ubicadas cerca de los puntos de demanda eléctrica gestionadas por los consumidores que pasan a ser también proveedores de energía y servicios a la red convirtiéndose en los denominados “prosumers“. Esta integración masiva de nuevas plantas de generación distribuida supone un desafío para la gestión de la red eléctrica que, tradicionalmente, ha respondido a un modelo de flujo de potencias unidireccional donde la potencia fluye desde grandes unidades de generación hacia los puntos de consumo, ajustando en todo momento la generación a la demanda y consiguiendo un balance de potencias que permitiese regular y controlar de manera efectiva los valores de tensión y frecuencia dentro de rangos admisibles. El nuevo modelo de generación distribuida basada en renovables requiere de nuevas herramientas y estrategias de gestión para hacer frente a la variabilidad que presentan estas energías renovables por su propia naturaleza y el gran número y dispersión geográfica de instalaciones que requieren una mayor flexibilidad ante nuevos retos en forma de flujo bidireccional de energía. Estas nuevas estrategias de gestión están apoyadas por los grandes avances realizados por las tecnologías de la información y la comunicación (TICs), que se han ido incorporando de forma paulatina de la mano de los operadores de red de cara a recoger diversas variables relacionadas con los estados de las unidades de generación y de los usuarios con objeto de optimizar la distribución y el consumo. En el caso de la fotovoltaica, hasta hace unos años, el coste y la complejidad de los sistemas de monitorización de las instalaciones fotovoltaicas limitaban su uso a las plantas fotovoltaicas de gran capacidad (a partir de 1 MW, tanto por motivos económicos como normativos), pero la aparición y la rápida evolución en el mercado del denominado Internet de las Cosas, IoT por sus siglas en inglés (Internet of Things), ha causado una explosión en la cantidad y variedad de soluciones de bajo costo que podrían permitir la implementación a gran escala de los sistemas de monitorización de manera rentable. Durante el desarrollo de esta tesis, de carácter eminentemente práctico, se ha trabajado en las tres capas que componen un sistema de IoT (percepción, comunicación y aplicación) para proponer un nuevo prototipo de gestión y comunicación de instalaciones fotovoltaicas de autoconsumo basado en estándares abiertos y soluciones de bajo coste. En la capa de percepción se han desarrollado y evaluado varios prototipos de sistemas de monitorización de acuerdo con los requisitos de la norma EC–61724, que describe las pautas generales para monitorizar y analizar el rendimiento de las plantas de energía fotovoltaica. Dentro de la capa de comunicaciones se ha trabajado en integración y evaluación de nuevos sistemas de comunicaciones de bajo coste, gran cobertura y baja demanda de energía (LPWAN) como medio para el intercambio datos en un entorno de Internet de las cosas (IoT). Por último, en la capa de aplicaciones se ha abordado el análisis de modelos de predicción de la generación de energía a corto plazo de estas instalaciones para proporcionar fiabilidad y estabilidad a la red, estudiándose tanto diferentes fuentes de datos de irradiancia para la aplicación de estos modelos como la influencia de los parámetros fundamentales de la red de comunicaciones en sus resultados. [ENG] This doctoral dissertation has been presented in the form of thesis by publication. The need to achieve a decarbonized economy to fight climate change has prompted several international commitments that oblige Spain and Europe to progressively reduce their greenhouse gas emissions until reaching climate neutrality in 2050. This goal can only be reached with a new energy model based on a massive integration of renewable energies. Among these technologies, photovoltaic solar energy is called to become one of the pillars to decarbonize the economy decarbonization thanks to its own technological maturity and the significant cost reduction, it has experienced in recent years. Within the different types of photovoltaic installations, one of the fastest growing is that of self-consumption, which are installations located near the points of electricity demand managed by the consumers themselves who also become providers of energy and services to the network, becoming the so-called prosumers.This massive integration of new distributed generation plants poses a challenge for the management of the electricity grid, which has traditionally responded to a unidirectional power flow model. In this unidirectional model, the power flows from the large generation units to the consumption points, adjusting the generation to achieve a power balance that allows effective regulation and control of the voltage and frequency values within the admissible ranges. The new decentralized distributed model requires new tools and management strategies to deal with the variability that renewable energies present due to their very nature and the large number and the geographical dispersion of installations that require greater flexibility to ensure a constant supply to cover demand and meet new challenges in the form of bidirectional flow of power These new management strategies are supported by the great advances made by information and communication technologies (ICTs) that have been gradually incorporated by the network operators in order to collect various variables related to generation units and consumer´s behavior in order to optimize distribution and consumption. In the case of photovoltaics, until a few years ago, the cost and complexity of monitoring systems for photovoltaic installations limited their use to large-capacity photovoltaic plants (from 1 MW, both for economic and regulatory reasons), but the appearance and rapid evolution in the market of the so-called Internet of Things, IoT, In this thesis, which has a practical approach, new contributions have been done to the three layers that make up an IoT system (perception, communication, and application) to propose a new management and communication prototype for selfconsumption photovoltaic installations based on open standards and low-cost IoT solutions. In the perception layer, several prototypes of monitoring systems have been developed and evaluated in accordance with the requirements of the EC–61724 standard, which describes the general guidelines for monitoring and analyzing the performance of photovoltaic power plants. Within the communications layer, work has been done on the integration and evaluation of new low-cost, high coverage, and low energy demand communications systems (LPWAN) to exchange data. Finally, in the applications layer, the analysis of short-term power generation prediction models for these facilities has been addressed to provide reliability and stability to the network, studying both different sources of irradiance data for the application of these models such as the influence of the fundamental parameters of the communications network in their results.Esta tesis doctoral se presenta bajo la modalidad de compendio de publicaciones. Está formada por un total de cinco artículos. 1. PV Module Monitoring System Based on Low-Cost Solutions: Wireless Raspberry Application and Assessment“. Paredes-Parra, J.M., Mateo-Aroca, A., Silvente- Niñirola, G., Bueso, M.C., Molina-García, A. 2018. Energies 11, no. 11: 3051. https://doi.org/10.3390/en11113051. 2. “An Alternative Internet-of-Things Solution Based on LoRa for PV Power Plants: Data Monitoring and Management“. Paredes-Parra, J.M., García-Sánchez, A.J., Mateo-Aroca, A., Molina-García, A. 2019. Energies 12, no. 5: 881. https://doi.org/10.3390/en12050881. 3. “A Characterization of Metrics for Comparing Satellite-Based and Ground-Measured Global Horizontal Irradiance Data: A Principal Component Analysis Application‘. Bueso, M.C., Paredes-Parra, J.M., Mateo-Aroca, A., Molina-García, A. 2020. Sustainability 12: 2454. https://doi.org/10.3390/su12062454. 4. “Sensitive Parameter Analysis for Solar Irradiance Short-Term Forecasting: Application to LoRa-Based Monitoring Technology“. Bueso, M.C., Paredes-Parra, J.M., Mateo-Aroca, A., Molina-García, A. 2022. Sensors (Basel) 22(4): 1499. https://doi.org/10.3390/s22041499. PMID: 35214398; PMCID: PMC8874705. 5. “Democratization of PV micro–generation system monitoring via an open source IoT gateway based on NB–IoT“. Paredes-Parra, J.M., Jiménez-Segura, R., Campos-Peñalver, D., Mateo-Aroca A., Ramallo-González, A.P., Molina-García, A. 2022. Sensors 22(13): 4966. https://doi.org/10.3390/s22134966.Escuela Internacional de Doctorado de la Universidad Politécnica de CartagenaUniversidad Politécnica de CartagenaPrograma de Doctorado en Energías Renovables y Eficiencia Energétic

Algorithmes d'adressage et routage pour des réseaux fortement mobiles à grande échelle

After successfully connecting machines and people later (world wide web), the new era of In-ternet is about connecting things. Due to increasing demands in terms of addresses, mobility, scalability, security and other new unattended challenges, the evolution of current Internet archi-tecture is subject to major debate worldwide. The Internet Architecture Board (IAB) workshop on Routing and Addressing report described the serious scalability problems faced by large backbone operators in terms of routing and addressing, illustrated by the unsustainable growth of the Default Free Zone (DFZ) routing tables. Some proposals tackled the scalability and IP semantics overload issues with two different approaches: evolutionary approach (backward com-patibility) or a revolutionary approach. Several design objectives (technical or high-level) guided researchers in their proposals. Mobility is definitely one of the main challenges.Inter-Vehicle Communication (IVC) attracts considerable attention from the research com-munity and the industry for its potential in providing Intelligent Transportation Systems (ITS) and passengers services. Vehicular Ad-Hoc Networks (VANETs) are emerging as a class of wire-less network, formed between moving vehicles equipped with wireless interfaces (cellular and WiFi) employing heterogeneous communication systems. A VANET is a form of mobile ad-hoc network that provides IVC among nearby vehicles and may involve the use of a nearby fixed equipment on the roadside. The impact of Internet-based vehicular services (infotainment) are quickly developing. Some of these applications, driver assistance services or traffic reports, have been there for a while. But market-enabling applications may also be an argument in favor of a more convenient journey. Such use cases are viewed as a motivation to further adoption of the ITS standards developed within IEEE, ETSI, and ISO.This thesis focuses on applying Future Internet paradigm to vehicle-to-Internet communica-tions in an attempt to define the solution space of Future Vehicular Internet. We first introduce two possible vehicle-to-Internet use cases and great enablers for IP based services : eHealth and Fully-electric Vehicles. We show how to integrate those use cases into IPv6 enabled networks. We further focus on the mobility architectures and determine the fundamental components of a mobility architecture. We then classify those approaches into centralized and distributed to show the current trends in terms of network mobility extension, an essential component to vehicular networking. We eventually analyze the performance of these proposals. In order to define an identifier namespace for vehicular communications, we introduce the Vehicle Identification Numbers are possible candidates. We then propose a conversion algorithm that preserves the VIN characteristics while mapping it onto usable IPv6 networking objects (ad-dresses, prefixes, and Mobile Node Identifiers). We make use of this result to extend LISP-MN protocol with the support of our VIN6 addressing architecture. We also apply those results to group IP-based communications, when the cluster head is in charge of a group of followers.Cette thèse a pour objectif de faire avancer l'état de l'art des communications basée sur Internet Protocol version 6 (IPv6) dans le domaine des réseaux véhiculaires, et ce dans le cadre des évolutions récentes de IP, notamment l'avènement du Future Internet. Le Future Internet (F.I.) définit un ensemble d'approches pour faire évoluer l'Internet actuel , en particulier l'émergence d'un Internet mobile exigeant en ressources. Les acteurs de ce domaine définissent les contraintes inhérentes aux approches utilisées historiquement dans l'évolution de l'architecture d'Internet et tentent d'y remédier soit de manière évolutive soit par une rupture technologique (révolutionnaire). Un des problèmes au centre de cette nouvelle évolution d'Internet est la question du nommage et de l'adressage dans le réseau. Nous avons entrepris dans cette thèse l'étude de ce problème, dans le cadre restreint des communications véhiculaires Internet.Dans ce contexte, l'état de l'art du Future Internet a mis en avant les distinctions des approches révolutionnaires comparées aux propositions évolutives basées sur IPv6. Les réseaux véhiculaires étant d'ores-et-déjà dotés de piles protocolaires comprenant une extension IPv6, nous avons entamé une approche évolutive visant à intégrer les réseaux véhiculaires au Future Internet. Une première proposition a été de convertir un identifiant présent dans le monde automobile (VIN, Numéro d'Identification de Véhicule) en un lot d'adresses réseau propres à chaque véhicule (qui est donc propriétaire de son adressage issu de son identifiant). Cette proposition étant centrée sur le véhicule, nous avons ensuite intégré ces communications basés dans une architecture globale Future Internet basée sur IPv6 (protocole LISP). En particulier, et avec l'adressage VIN, nous avons défini un espace d'adressage indépendant des fournisseurs d'accès à Internet où le constructeur automobile devient acteur économique fournissant des services IPv6 à sa flotte de véhicules conjointement avec les opérateurs réseau dont il dépend pour transporter son trafic IP. Nous nous sommes ensuite intéressés à l'entourage proche du véhicule afin de définir un nouveau mode de communication inter-véhiculaire à Internet: le V2V2I (Angl. Vehicle-to-Vehicle-to-Infrastructure). Jusqu'à présent, les modes de transmission de données à Internet dans le monde du véhicule consistaient en des topologies V2I, à savoir véhicule à Internet, où le véhicule accède à l'infrastructure directement sans intermédiaire. Dans le cadre des communications véhiculaires à Internet, nous proposons une taxonomie des méthodes existantes dans l'état de l'art. Les techniques du Future Internet étant récentes, nous avons étendu notre taxonomie par une nouvelle approche basée sur la séparation de l'adressage topologique dans le cluster de celui de l'infrastructure. Le leader du cluster s'occupe d'affecter les adresses (de son VIN) et de gérer le routage à l'intérieur de son cluster. La dernière contribution consiste en la comparaison des performances des protocoles de gestion de mobilité, notamment pour les réseaux de véhicules et des communications de type vehicule-à-Internet. Dans ce cadre, nous avons proposé une classification des protocoles de gestion de mobilité selon leur déploiement: centralisé (basé réseau ou host) et distribué. Nous avons ensuite évalué les performances en modélisant les durées de configurations et de reconfigurations des différents protocoles concernés