Understanding the applicability of terahertz flow-guided nano-networksfor medical applications

Terahertz-based nano-networks are emerging as a groundbreaking technology able to play a decisive role in future medical applications owing to their ability to precisely quantify figures, such as the viral load in a patient or to predict sepsis shock or heart attacks before they occur. Due to the extremely limited size of the devices composing these nano-networks, the use of the Terahertz (THz) band has emerged as the enabling technology for their communication. However, the characteristics of the THz band, which strictly reduce the communication range inside the human body, together with the energy limitations of nano-nodes make the in-body deployment of nano-nodes a challenging task. To overcome these problems, we propose a novel in-body flow-guided nano-network architecture consisting of three different devices: i) nano-node, ii) nano-router, and iii) bio-sensor. As the performance of this type of nano-network has not been previously explored, a theoretical framework capturing all its particularities is derived to properly model its behavior and evaluate its feasibility in real medical applications. Employing this analytical model, a thorough sensitivity study of its key parameters is accomplished. Finally, we analyze the terahertz flow-guided nano-network design to satisfy the requirements of several medical applications of interest

Contribution to the integration, performance improvement, and smart management of data and resources in the Internet of Things

[SPA] Esta tesis doctoral se presenta bajo la modalidad de compendio de publicaciones.[ENG] This doctoral dissertation has been presented in the form of thesis by publication. The IoT has seen a tremendous growth in the last few years. Not only due to its potential to transform societies, but also as an enabling technology for many other technological advances. Unfortunately, the IoT is a relatively recent paradigm that lacks the maturity of other well-established (not so recent) revolutions like the internet itself or Wireless Sensor Networks; upon which the IoT is built. The presented Thesis contributes to this maturation process by researching on the underlying communication mechanisms that enable a truly ubiquitous and effective IoT. As a Thesis by compilation, 5 relevant articles are introduced and discussed. Each of such articles delve into different key aspects that, in their own way, help closing the gap between what the IoT is expected to bring and what the IoT actually brings. As thoroughly commented throughout the main text, the comprehensive approach taken in this Thesis ensures that multiple angles of the same plane --the communication plane-- are analyzed and studied. From the mathematical analysis of how electromagnetic waves propagate through complex environments to the utilization of recent Machine Learning techniques, this Thesis explore a wide range of scientific and researching tools that are shown to improve the final performance of the IoT. In the first three chapters of this document, the reader will be introduced to the current context and state-of-the-art of the IoT while, at the same time, the formal objectives of this Thesis are outlined and set into such a global context. In the next five chapters, the five corresponding articles are presented and commented. For each and every of these articles: a brief abstract, a methodology summary, a highlight on the results and contributions and final conclusions are also added. Lastly, in the two last chapters, the final conclusions and future lines of this Thesis are commented.Los artículos que componen la tesis son los siguientes: 1. R. M. Sandoval, A.-J. J. Garcia-Sanchez, F. Garcia-Sanchez, and J. Garcia-Haro, \Evaluating the More Suitable ISM Frequency Band for IoT-Based Smart Grids: A Quantitative Study of 915 MHz vs. 2400 MHz," Sensors, vol. 17, no. 1, p. 76, Dec. 2016. 2. R. M. Sandoval, A.-J. J. Garcia-Sanchez, J.-M. M. Molina-Garcia-Pardo, F. Garcia-Sanchez, and J. Garcia-Haro, \Radio-Channel Characterization of Smart Grid Substations in the 2.4-GHz ISM Band," IEEE Trans. Wirel. Commun., vol. 16, no. 2, pp. 1294{1307, Feb. 2017. 3. R. M. Sandoval, A. J. Garcia-Sanchez, and J. Garcia-Haro, \Improving RSSI-based path-loss models accuracy for critical infrastructures: A smart grid substation case-study," IEEE Trans. Ind. Informatics, vol. 14, no. 5, pp. 2230{2240, 2018. 4. R. M. Sandoval, A.-J. Garcia-Sanchez, J. Garcia-Haro, and T. M. Chen, \Optimal policy derivation for Transmission Duty-Cycle constrained LPWAN," IEEE Internet Things J., vol. 5, no. 4, pp. 1{1, Aug. 2018. 5. R. M. Sandoval, S. Canovas-Carrasco, A. Garcia-Sanchez, and J. Garcia-Haro, \Smart Usage of Multiple RAT in IoT-oriented 5G Networks: A Reinforcement Learning Approach," in 2018 ITU Kaleidoscope: Machine Learning for a 5G Future (ITU K), 2018, pp. 1-8.Escuela Internacional de Doctorado de la Universidad Politécnica de CartagenaUniversidad Politécnica de CartagenaPrograma de Doctorado en Tecnologías de la Información y las Comunicaciones por la Universidad Politécnica de Cartagen

Digital Forensics AI: on Practicality, Optimality, and Interpretability of Digital Evidence Mining Techniques

Digital forensics as a field has progressed alongside technological advancements over the years, just as digital devices have gotten more robust and sophisticated. However, criminals and attackers have devised means for exploiting the vulnerabilities or sophistication of these devices to carry out malicious activities in unprecedented ways. Their belief is that electronic crimes can be committed without identities being revealed or trails being established. Several applications of artificial intelligence (AI) have demonstrated interesting and promising solutions to seemingly intractable societal challenges. This thesis aims to advance the concept of applying AI techniques in digital forensic investigation. Our approach involves experimenting with a complex case scenario in which suspects corresponded by e-mail and deleted, suspiciously, certain communications, presumably to conceal evidence. The purpose is to demonstrate the efficacy of Artificial Neural Networks (ANN) in learning and detecting communication patterns over time, and then predicting the possibility of missing communication(s) along with potential topics of discussion. To do this, we developed a novel approach and included other existing models. The accuracy of our results is evaluated, and their performance on previously unseen data is measured. Second, we proposed conceptualizing the term “Digital Forensics AI” (DFAI) to formalize the application of AI in digital forensics. The objective is to highlight the instruments that facilitate the best evidential outcomes and presentation mechanisms that are adaptable to the probabilistic output of AI models. Finally, we enhanced our notion in support of the application of AI in digital forensics by recommending methodologies and approaches for bridging trust gaps through the development of interpretable models that facilitate the admissibility of digital evidence in legal proceedings

Digital Forensics AI: on Practicality, Optimality, and Interpretability of Digital Evidence Mining Techniques

Digital forensics as a field has progressed alongside technological advancements over the years, just as digital devices have gotten more robust and sophisticated. However, criminals and attackers have devised means for exploiting the vulnerabilities or sophistication of these devices to carry out malicious activities in unprecedented ways. Their belief is that electronic crimes can be committed without identities being revealed or trails being established. Several applications of artificial intelligence (AI) have demonstrated interesting and promising solutions to seemingly intractable societal challenges. This thesis aims to advance the concept of applying AI techniques in digital forensic investigation. Our approach involves experimenting with a complex case scenario in which suspects corresponded by e-mail and deleted, suspiciously, certain communications, presumably to conceal evidence. The purpose is to demonstrate the efficacy of Artificial Neural Networks (ANN) in learning and detecting communication patterns over time, and then predicting the possibility of missing communication(s) along with potential topics of discussion. To do this, we developed a novel approach and included other existing models. The accuracy of our results is evaluated, and their performance on previously unseen data is measured. Second, we proposed conceptualizing the term “Digital Forensics AI” (DFAI) to formalize the application of AI in digital forensics. The objective is to highlight the instruments that facilitate the best evidential outcomes and presentation mechanisms that are adaptable to the probabilistic output of AI models. Finally, we enhanced our notion in support of the application of AI in digital forensics by recommending methodologies and approaches for bridging trust gaps through the development of interpretable models that facilitate the admissibility of digital evidence in legal proceedings

Contribution to the design of nanodevices and communication protocols for nanonetworks in the THz band

Mención Europeo / Mención Internacional: Concedido[SPA] Esta tesis doctoral se presenta bajo la modalidad de compendio de publicaciones.[ENG] This doctoral dissertation has been presented in the form of thesis by publication. Electromagnetic (EM) nano-communications is a new paradigm encompassing all concerns related to the exchange of information among devices operating in the Terahertz band (0.1-10 THz). A nano-network infrastructure consisting of a high number of nano-devices should be designed to ensure robust, reliable, and coordinated data transmission. This will enable a plethora of forthcoming applications and services in different research fields, such as medicine, environmental science, on-chip communications, or software-defined materials, which will lead to outstanding advances. Nevertheless, EM nano-communications is a recent paradigm that lacks the maturity of other well-established communication fields, so the presented thesis contributes to this maturation process by researching both the hardware and the communication mechanisms upon which THz-based nano-networks could operate. As a Thesis by compilation, the 7 articles published during this Ph.D. program are presented and commented. Each of such articles looks into different key aspects that help closing the gap between theory and practice in THz-based nano-communications. Thus, in the first two chapters of this document, the reader will be introduced to the context and objectives of the thesis. In particular, the second chapter is divided into two subsections: general objectives, which are set into the global background; and specific objectives, grouped by publication. In the next seven chapters, the seven corresponding articles are presented and commented. For each of them, a brief summary, the methodology followed, an overview of the results and contributions, and final conclusions are included. Finally, in the two last chapters, the final conclusions and future lines of this thesis are discussed.Los artículos que constituyen la tesis son los siguientes: 1. S. Canovas-Carrasco, A.-J. Garcia-Sanchez, F. Garcia-Sanchez, and J. Garcia-Haro, \Conceptual design of a nano-networking device," Sensors, vol. 16, no. 12, p. 2104, Dec. 2016. 2. S. Canovas-Carrasco, A.-J. Garcia-Sanchez, and J. Garcia-Haro, \The IEEE 1906.1 Standard: Nanocommunications as a new source of data," 2017 ITU Kaleidoscope: Challenges for a Data-Driven Society (ITU K), Nanjing, 2017, pp. 1-7.3. S. Canovas-Carrasco, A.-J. Garcia-Sanchez, and J. Garcia-Haro, \A nanoscale communication network scheme and energy model for a human hand scenario," Nano Communication Networks, vol. 15, pp. 17{27, Mar. 2018. 4. S. Canovas-Carrasco, A.-J. Garcia-Sanchez, and J. Garcia-Haro, \On the Nature of Energy-Feasible Wireless Nanosensor Networks," Sensors, vol. 18, no. 5, p. 1356, Apr. 2018. 5. S. Canovas-Carrasco, A.-J. Garcia-Sanchez, and J. Garcia-Haro, \The IEEE 1906.1 standard: Some guidelines for strengthening future normalization in electromagnetic nanocommunications," IEEE Commun. Stand. Mag., vol. 2, no. 4, pp. 26{32, Dec. 2018. 6. S. Canovas-Carrasco, R. M. Sandoval, A.-J. Garcia-Sanchez, and J. Garcia-Haro, \Optimal Transmission Policy Derivation for IoNT Flow-Guided Nano-Sensor Networks," IEEE Internet of Things Journal, vol. 6, no. 2, pp. 2288-2298, Apr. 2019. 7. R. Asorey-Cacheda, S. Canovas-Carrasco, A.-J. Garcia-Sanchez, J. Garcia-Haro, \An Analytical Approach to Flow-Guided Nanocommunication Networks," Sensors, vol. 20, no. 5, p. 1332, Feb. 2020.Escuela Internacional de Doctorado de la Universidad Politécnica de CartagenaUniversidad Politécnica de CartagenaPrograma de Doctorado de Tecnologís de la Información y las Comunicacione