Energy efficient CM2M communications in E-healthcare systems

In this paper, cognitive machine to machine (CM2M) gateways in e-healthcare systems are presented by accessing a number of channels via periodic sensing and spectrum handoff. An optimal energy efficient spectrum management mechanism with multiple thresholds is proposed. The developed mechanism aims to reduce energy consumption in the system by optimizing the spectrum sensing and the channel switching, while decreasing the probability of collision, with assuring the reliability thresholds, throughput, and delay. Subsequently an antenna selection sensing (ASS) scheme is used to improve sensing accuracy. The simulation results show that the energy efficiency of the CM2M gateways can be improved significantly

Ecosystemic Evolution Feeded by Smart Systems

Information Society is advancing along a route of ecosystemic evolution. ICT and Internet advancements, together with the progression of the systemic approach for enhancement and application of Smart Systems, are grounding such an evolution. The needed approach is therefore expected to evolve by increasingly fitting into the basic requirements of a significant general enhancement of human and social well-being, within all spheres of life (public, private, professional). This implies enhancing and exploiting the net-living virtual space, to make it a virtuous beneficial integration of the real-life space. Meanwhile, contextual evolution of smart cities is aiming at strongly empowering that ecosystemic approach by enhancing and diffusing net-living benefits over our own lived territory, while also incisively targeting a new stable socio-economic local development, according to social, ecological, and economic sustainability requirements. This territorial focus matches with a new glocal vision, which enables a more effective diffusion of benefits in terms of well-being, thus moderating the current global vision primarily fed by a global-scale market development view. Basic technological advancements have thus to be pursued at the system-level. They include system architecting for virtualization of functions, data integration and sharing, flexible basic service composition, and end-service personalization viability, for the operation and interoperation of smart systems, supporting effective net-living advancements in all application fields. Increasing and basically mandatory importance must also be increasingly reserved for human–technical and social–technical factors, as well as to the associated need of empowering the cross-disciplinary approach for related research and innovation. The prospected eco-systemic impact also implies a social pro-active participation, as well as coping with possible negative effects of net-living in terms of social exclusion and isolation, which require incisive actions for a conformal socio-cultural development. In this concern, speed, continuity, and expected long-term duration of innovation processes, pushed by basic technological advancements, make ecosystemic requirements stricter. This evolution requires also a new approach, targeting development of the needed basic and vocational education for net-living, which is to be considered as an engine for the development of the related ‘new living know-how’, as well as of the conformal ‘new making know-how’

Electroactive poly(vinylidene fluoride) based materials: recent progress, challenges and opportunities

A poly(vinylidene fluoride) (PVDF) and its copolymers are polymers that, in specific crystalline phases, show high dielectric and piezoelectric values, excellent mechanical behavior and good thermal and chemical stability, suitable for many applications from the biomedical area to energy devices. This chapter introduces the main properties, processability and polymorphism of PVDF. Further, the recent advances in the applications based on those materials are presented and discussed. Thus, it shown the key role of PVDF and its copolymers as smart and multifunctional material, expanding the limits of polymer-based technologies.FCT (Fundação para a Ciência e Tecnologia) for financial support under the framework of Strategic Funding grants UID/FIS/04650/2019, and UID/QUI/0686/2019 and project PTDC/FIS-MAC/28157/2017, PTDC/BTMMAT/28237/2017, PTDC/EMD-EMD/28159/2017. The author also thanks the FCT for financial support under grant SFRH/BPD/112547/2015 (C.M.C.), SFRH/BPD/98109/2013 (V.F.C.), SFRH/BD/140698/2018 (R.B.P.), SFRH/BPD/96227/2013 (P.M.), SFRH/BPD/121526/2016 (D.M.C.), SFRH/BPD/97739/2013 (V. C.), SFRH/BPD/90870/2012 (C.R.). Financial support from the Spanish Ministry of Economy and Competitiveness (MINECO) through project MAT2016-76039-C4-3-R (AEI/FEDER, UE) (including FEDER financial support) and from the Basque Government Industry and Education Departments under the ELKARTEK, HAZITEK and PIBA (PIBA-2018-06)

Optical Microwave Signal Generation for Data Transmission in Optical Networks

The massive growth of telecommunication services and the increasing global data traffic boost the development, implementation, and integration of different networks for data transmission. An example of this development is the optical fiber networks, responsible today for the inter-continental connection through long-distance links and high transfer rates. The optical networks, as well as the networks supported by other transmission media, use electrical signals at specific frequencies for the synchronization of the network elements. The quality of these signals is usually determined in terms of phase noise. Due to the major impact of the phase noise over the system performance, its value should be minimized. The research work presented in this document describes the design and implementation of an optoelectronic system for the microwave signal generation using a vertical-cavity surface-emitting laser (VCSEL) and its integration into an optical data transmission system. Considering that the proposed system incorporates a directly modulated VCSEL, a theoretical and experimental characterization was developed based on the laser rate equations, dynamic and static measurements, and an equivalent electrical model of the active region. This procedure made possible the extraction of some VCSEL intrinsic parameters, as well as the validation and simulation of the VCSEL performance under specific modulation conditions. The VCSEL emits in C-band, this wavelength was selected because it is used in long-haul links. The proposed system is a self-initiated oscillation system caused by internal noise sources, which includes a VCSEL modulated in large signal to generate optical pulses (gain switching). The optical pulses, and the optical frequency comb associated, generate in electrical domain simultaneously a fundamental frequency (determined by a band-pass filter) and several harmonics. The phase noise measured at 10 kHz from the carrier at 1.25 GHz was -127.8 dBc/Hz, and it is the lowest value reported in the literature for this frequency and architecture. Both the jitter and optical pulse width were determined when different resonant cavities and polarization currents were employed. The lowest pulse duration was 85 ps and was achieved when the fundamental frequency was 2.5 GHz. As for the optical frequency comb, it was demonstrated that its flatness depends on the electrical modulation conditions. The flattest profiles are obtained when the fundamental frequency is higher than the VCSEL relaxation frequency. Both the electrical and the optical output of the system were integrated into an optical transmitter. The electrical signal provides the synchronization of the data generating equipment, whereas the optical pulses are employed as an optical carrier. Data transmissions at 155.52 Mb/s, 622.08 Mb/s and 1.25 Gb/s were experimentally validated. It was demonstrated that the fundamental frequency and harmonics could be extracted from the optical data signal transmitted by a band-pass filter. It was also experimentally proved that the pulsed return-to-zero (RZ) transmitter at 1.25 Gb/s, achieves bit error rates (BER) lower than $10^{-9}$ when the optical power at the receiver is higher than -33 dBm.La masificación de los servicios de telecomunicaciones y el creciente tráfico global de datos han impulsado el desarrollo, despliegue e integración de diferentes redes para la transmisión de datos. Un ejemplo de este despliegue son las redes de fibra óptica, responsables en la actualidad de la interconexión de los continentes a través de enlaces de grandes longitudes y altas tasas de transferencia. Las redes ópticas, al igual que las redes soportadas por otros medios de transmisión, utilizan señales eléctricas a frecuencias específicas para la sincronización de los elementos de red. La calidad de estas señales es determinante en el desempeño general del sistema, razón por la que su ruido de fase debe ser lo más pequeño posible. El trabajo de investigación presentado en este documento describe el diseño e implementación de un sistema optoelectrónico para la generación de señales microondas utilizando diodos láser de cavidad vertical (VCSEL) y su integración en un sistema de transmisión de datos óptico. Teniendo en cuenta que el sistema propuesto incorpora un láser VCSEL modulado directamente, se desarrolló una caracterización teórico-experimental basada en las ecuaciones de evolución del láser, mediciones dinámicas y estáticas, y un modelo eléctrico equivalente de la región activa. Este procedimiento posibilitó la extracción de algunos parámetros intrínsecos del VCSEL, al igual que la validación y simulación de su desempeño bajo diferentes condiciones de modulación. El VCSEL utilizado emite en banda C y fue seleccionado considerando que esta banda es comúnmente utilizada en enlaces de largo alcance. El sistema propuesto consiste en un lazo cerrado que inicia la oscilación gracias a las fuentes de ruido de los componentes y modula el VCSEL en gran señal para generar pulsos ópticos (conmutación de ganancia). Estos pulsos ópticos, que en el dominio de la frecuencia corresponden a un peine de frecuencia óptico, son detectados para generar simultáneamente una frecuencia fundamental (determinada por un filtro pasa banda) y varios armónicos. El ruido de fase medido a 10 kHz de la portadora a 1.25 GHz fue -127.8 dBc/Hz, y es el valor más bajo reportado en la literatura para esta frecuencia y arquitectura. Tanto la fluctuación de fase (jitter) y el ancho de los pulsos ópticos fueron determinados cuando diferentes cavidades resonantes y corrientes de polarización fueron empleadas. La duración de pulso más baja fue 85 ps y se obtuvo cuando la frecuencia fundamental del sistema era 2.5 GHz. En cuanto al peine de frecuencia óptico, se demostró que su planitud (flatness) depende de las condiciones eléctricas de modulación y que los perfiles más planos se obtienen cuando la frecuencia fundamental es superior a la frecuencia de relajación del VCSEL. Tanto la salida eléctrica como la salida óptica del sistema fueron integradas en un transmisor óptico. La señal eléctrica permite la sincronización de los equipos encargados de generar los datos, mientras que los pulsos ópticos son utilizados como portadora óptica. La transmisión de datos a 155.52 Mb/s, 622.08 Mb/s y 1.25 Gb/s fue validada experimentalmente. Se demostró que la frecuencia fundamental y los armónicos pueden ser extraídos de la señal óptica de datos transmitida mediante un filtro pasa banda. También se comprobó experimentalmente que el transmisor de datos pulsados con retorno a cero (RZ) a 1.25 Gb/s, logra tasas de error de bit (BER) menores a 10-9 cuando la potencia óptica en el receptor es mayor a -33 dBm.Gobernación de NariñoBPIN 2013000100092Doctorad

Understanding the Structure of Materials at the Intersection of Rationalisation, Prediction and Big Data

Theoretical materials science has a large and growing role to play in modern society thanks to its ability to deliver materials with new and interesting properties. The properties of any material are, on some level, a function of its internal structure. In this work we combine three important tools spanning the last 100 years of materials research, rationalisation, prediction and big data in an attempt to understand the factors that underpin the stability of ordered structures and to build an understanding of structure that is agnostic of a particular element or building block. We apply rationalisation to data mining of the Inorganic Crystal Structure Database, using various proposed structure descriptors to probe the factors affecting structure stability. Extensive prediction is performed on the Fe-Ni-Si system at inner earth core pressures to determine the phases most likely to be present, yielding a new, stable, Ni-Si structure. A new prediction technique for 2D grain boundaries is presented that doubles the size of system that can reasonably be studied at the ab initio level of theory. The structurally rich phosphorus and arsenic systems are investigated using structure prediction, producing new metastable structures. Finally, we use a simple model for particles that attract at long range and repel at short to probe all the possible binary structures over a wide range of stoichiometries. By carrying out prediction over a wide range of potential parameters we build a database of almost 20M entries. Contained within are a number of unreported structures including many in parts of parameter space that go beyond the periodic table in terms of size and bond energy ratios. Our work provides hints that these hypothetical structures could be realised in self assembling systems made up from constituents with tunable interactions opening the door to the possibility of new properties

Control Systems for Silicon Photonic Microring Devices

The continuing growth of microelectronics in speed, scale, and complexity has led to a looming bandwidth bottleneck for traditional electronic interconnects. This has precipitated the penetration of optical interconnects to smaller, more localized scales, in such applications as data centers, supercomputers, and access networks. For this next generation of optical interconnects, the silicon photonic platform has received wide attention for its ability to manifest, more economical, high-performance photonics. The high index contrast and CMOS compatibility of the silicon platform give the potential to intimately integrate small footprint, power-efficient, high-bandwidth photonic interconnects with existing high-performance CMOS microelectronics. Within the silicon photonic platform, traditional photonic elements can be manifested with smaller footprint and higher energy-efficiency. Additionally, the high index contrast allows the successful implementation of silicon microring-based devices, which push the limits on achievable footprint and energy-efficiency metrics. While laboratory demonstrations have testified to their capabilities as powerful modulators, switches, and filters, the commercial implementation of microring-based devices is impeded by their susceptibility to fabrication tolerances and their inherent temperature sensitivity. This work develops and demonstrates methods to resolve the aforementioned sensitivities of microring-based devices. Specifically, the use of integrated heaters to thermally tune and lock microring resonators to laser wavelengths, and the underlying control systems to enable such functionality. The first developed method utilizes power monitoring to show the successful thermal stabilization of a microring modulator under conditions that would normally render it inoperational. In a later demonstration, the photodetector used for power monitoring is co-integrated with the microring modulator, again demonstrating thermal stabilization of a microring modulator and validating the use of defect-enhanced silicon photodiodes for on-chip control systems. Secondly, a generalized method is developed that uses dithering signals to generate anti-symmetric error signals for use in stabilizing microring resonators. A control system utilizing a dithering signal is shown to successfully wavelength lock and thermally stabilize a microring resonator. Characterizations are performed on the robustness and speed of the wavelength locking process when using dithering signals. An FPGA implementation of the control system is used to scale to a WDM microring demultiplexer, demonstrating the simultaneous wavelength locking of multiple microring resonators. Additionally, the dithering technique is adopted to create control systems for microring-based switches, which have traditionally posed a challenging problem due to their multi-state configurations. The aforementioned control systems are rigorously tested for applications with high speed data and analyzed for power efficiency and scalability to show that they can successfully scale to commercial implementations and be the enabling factor in the commercial deployment of microring-based devices

Développement et investigation de nouveaux modèles en médecine computationnelle

In this thesis, our objective is to contribute to the development of decision support toolsin healthcare, through mathematical and agent-based modeling.The two topics we are interested in in this work are the evolution of cancer and the spreadof the coronavirus. Both biological phenomena can be modeled by differential equationson the one hand and by multi-agents on the other hand and the numerical simulation byboth approaches provides interesting decision support tools in both cases.In the first part of this thesis, we are interested in the study of the development ofan untreated cancerous tumor. To do so, two different approaches are adopted. In thefirst approach, the evolution of the tumor mass is followed at the macroscopic level. Thetumor is modeled as a cluster of cells evolving with time according to the developmentof the tumor. Modeling using a system of partial differential equations, allows us in thiscase to calculate the densities of the different cells composing the tumor as well as tosimulate the tumor shape evolution. The tracking of the tumor contour is done usingthe level-set method for which the normal velocity is calculated in two different ways.The first one by using Darcy law to transport the level-set function values and the sec-ond one by using shape optimization to compute the deformation velocity through anadjoint problem. The second approach is at the microscopic level. Each cell is modeledindividually as an agent in continuous interaction with its environment and with othercells. The modeling uses in this case multi-agent simulation to describe the behavior ofthe different types of cells and a partial differential equation to describe the diffusion ofthe nutrient in their environment. A study of the sensitivity of this model to each of itsparameters is then conducted to better analyze and understand the hybrid model. Wethen study the specific case of prostate cancer under combined hormone therapy and lowdose rate brachytherapy. We use a system of partial differential equations to describe thebehavior of prostate cells and their response to different treatments. The findings werediscussed with oncologists. Numerical simulations allow to define a treatment strategy tobest combine the effects of the two treatments on the tumor but also on the quality of lifeof the patients, which deteriorates due to the side effects of each therapy. The numericalresolution of the partial differential equations is done under FreeFem++ software usinga finite element method. In the case of the hybrid tumor growth model, the nutrientdiffusion equation is solved in Matlab using a finite difference method and coupled toNetlogo for the agent-based simulations.In the second part of the work, using multi-agent modeling, we simulated the spreadof the coronavirus 2019 disease using compartmental models. We studied the impact ofdifferent sanitary measures on the evolution of the pandemic and implemented a decisionsupport and epidemiological surveillance tool for the monitoring of the sanitary crisiscaused by Covid-19. The multi-agent simulations are implemented under the Netlogo software.Dans cette thèse, notre objectif est de contribuer au développement d’outils d’aide à ladécision dans le domaine de la santé, en nous basant sur la modélisation mathématiqueet la modélisation à base d’agents.Les deux sujets auxquels nous nous intéressons dans ce travail, sont l'évolution du cancer et la propagation du coronavirus. Les deux phénomènes biologiques peuvent êtremodélisés par des équations différentielles d’une part et par les multi-agents d’autre partet la simulation numérique par les deux approches fournit des outils d’aide à la décisionintéressants dans les deux cas.Dans une première partie de ce mémoire, nous nous intéressons, à l’étude du développement d’une tumeur cancéreuse non encore traitée. Pour ce faire, deux différentesapproches sont adoptées. Dans la première approche le suivi de l’évolution de la massetumorale se fait au niveau macroscopique. La tumeur est modélisée en tant qu’amas decellules disposant d’une densité et d’une forme évoluant suivant le développement de latumeur. La modélisation utilisant un système d’équations aux dérivées partielles, nouspermet dans ce cas de calculer les densités des différents types de cellules composantla tumeur et de simuler l’évolution de la forme de la tumeur. Le suivi du contour de latumeur est fait à l’aide de la méthode des lignes de niveaux pour laquelle la vitesse normaleest calculée de deux fa ̧cons différentes. La première en utilisant la vitesse de Darcy pourtransporter les valeurs de la fonction level-set et la deuxième en utilisant l’optimisationde forme pour calculer la vitesse de déformation en passant par un problème adjoint. Laseconde approche se fait au niveau microscopique. Chaque cellule est modélisée individuellement en tant qu’agent en interaction continue avec son environnement ainsi qu’avec les autres cellules. La modélisation utilise dans ce cas la simulation multi-agents pour décrire le comportement des différents types de cellules ainsi qu’une équation aux dérivées partielles pour décrire la diffusion du nutriment dans leur environnement. Une étude dela sensibilité de ce modèle à chacun de ses paramètres est ensuite menée pour mieux anal-yser le modèle et le comprendre. Nous étudions par la suite le cas spécifique du cancerde la prostate sous traitements combinés d’hormonothérapie et curiethérapie à bas débitde dose. Nous utilisons un système d’équations aux dérivées partielles pour décrire lecomportement des cellules de la prostate et leur réponse aux différents traitements. Lessimulations numériques permettent de définir une stratégie thérapeutique pour combinerau mieux les effets des deux traitements sur la tumeur mais aussi sur la qualité de vie despatients qui se dégrade à cause des effets secondaires de chaque thérapie. Les résultatsobtenus ont été discuté avec des oncologues. La résolution numérique des équationsaux dérivées partielles est faite sous le logiciel FreeFem++ en utilisant la méthode deséléments finis. Dans le cas du modèle hybride de croissance tumorale, l’équation de dif-fusion du nutriment est résolue sous Matlab en utilisant la méthode des différences finieset reliée à Netlogo pour les simulations à base d’agents.Dans la deuxième partie du travail, en utilisant la simulation multi-agents, nous avonssimulé la propagation du Covid-19 à l’aide des modèles compartimentaux. Nous avons étudié l’impact de différentes mesures sanitaires sur l’évolution de la pandémie et misen place un outil d’aide à la décision et de surveillance épidémiologique pour le suivide la crise sanitaire engendrée par la maladie du Covid-19. Les simulations utilisant lesmulti-agents sont implémentées sous le logiciel Netlogo

Implications for EU Policies and Institutions

The consolidation and further development of the European Union depends on a great deal of trust from its citizens: trust in its integrity, trust in its purpose, and trust in its values. Trust is the belief that people and organisations will behave in a predictable and reliable manner. To trust, in essence, is to take a risk based on positive expectations about others. Many observers detect 'a crisis of trust' today, especially since the recent financial and economic crisis in Europe. We see strong signals that there is a serious lack of trust in public authorities, both at the European and the national level. Between 2007 and 2013 citizens' trust in the EU and in national governments and parliaments fell dramatically. Trust is fundamental for the good functioning of the society and the economy. Institutions are built on it. It is correlated with fairness and responsiveness to people's concerns, and helps sustain a cooperative social climate, as well as foster compliance with laws and standards. Participation in community and civic affairs is less risky and more rewarding when people trust each other. Because of its importance for society, the European Commission is prioritising the need to regain the trust of citizens in the European project. President Juncker's political guidelines underline that the EU is not just a big common market, it is also a Union of shared values. Using a foresight approach, this volume makes a major contribution to better understanding the disruptive effects that an erosion or collapse of trust could have for Europe: for its science, for its political and justice systems, for the regulation of economic activities, social cohesion, for public administrations and for the Internet and cyberspace in general. Its chapters elaborate not only on the potential disruptions, but also on possible policy responses to counteract a further loss of societal trust. The book is an essential contribution to a rich and pragmatic understanding of the 'crisis of trust' in Europe. It is the kind of contribution that citizens expect from foresight analysis and one that I am sure will feed into many EU policy discussions for the years to come

Applications of machine to machine communication in remote healthcare systems

Wireless Machine-To-Machine (M2M) communications in healthcare systems will play a large part in the medical sector in the near future, enabling a number of applications to speed up medical treatment, decreasing the cost, and increasing the flexibility and efficiency of the hospitals and medical bodies. The work undertaken in this thesis is to improve the spectrum and energy efficiency of M2M communications in the medical sector by exploiting Cognitive radio (CR) technology. First, the thesis considered an efficient aggregation-based spectrum assignment algorithm for Cognitive Machine-To-Machine (CM2M) networks. The proposed algorithm takes practical thresholds including Co-Channel Interference (CCI) among CM2M devices, interference to the Primary Users (PUs), and Maximum Aggregation Span (MAS) into consideration. Simulation results clearly show that the developed algorithm outperforms State of The Art (SOTA) algorithms in terms of network capacity and spectrum utilization. The developed algorithm can improve data rate of CM2M devices by at least 23% compared with the SOTA algorithms. Furthermore, this thesis presents an optimal energy efficient spectrum management mechanism with multiple thresholds. The developed mechanism aims to reduce energy consumption in the system by optimizing spectrum sensing and channel switching, while at the same time decreasing the probability of collision and assuring the reliability thresholds, throughput, and delay. Subsequently, an Antenna Selection Sensing (ASS) scheme is used to improve sensing accuracy. The simulation results show that the energy efficiency of the CM2M gateways can be improved by at least 35%. In addition, the thesis considered an Energy-Efficient Channel Selecting (EECS) algorithm for CM2M communications in the healthcare system. The proposed algorithm aims to select the best available channels to improve CM2M communication quality and reduce energy consumption in the system overall. Accordingly, the algorithm reduced the probability of CM2M gateways switching between available channels and improved the energy efficiency by at least 45%. The efficiency of the algorithm is discussed and demonstrated through simulations