Energy Efficiency of Hybrid-Power HetNets: A Population-like Games Approach

In this paper, a distributed control scheme based on population games is proposed. The controller is in charge of dealing with the energy consumption problem in a Heterogeneous Cellular Network (HetNet) powered by hybrid energy sources (grid and renewable energy) while guaranteeing appropriate quality of service (QoS) level at the same time. Unlike the conventional approach in population games, it considers both atomicity and non-anonymity. Simulation results show that the proposed population-games approach reduces grid consumption by up to about 12% compared to the traditional best-signal level association policy.U.S. Air Force Office of Scientific Research FA9550-17-1-0259Ministerio de Cultura y Deporte DPI2016-76493-C3-3-RMinisterio de Economía y Empresa DPI2017-86918-

Atomicity and non-anonymity in population-like games for the energy efficiency of hybrid-power HetNets

© 2018 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.In this paper, the user–base station (BS) association problem is addressed to reduce grid consumption in heterogeneous cellular networks (HetNets) powered by hybrid energy sources (grid and renewable energy). The paper proposes a novel distributed control scheme inspired by population games and designed considering both atomicity and non-anonymity – i.e., describing the individual decisions of each agent. The controller performance is considered from an energy–efficiency perspective, which requires the guarantee of appropriate qualityof-service (QoS) levels according to renewable energy availability. The efficiency of the proposed scheme is compared with other heuristic and optimal alternatives in two simulation scenarios. Simulation results show that the proposed approach inspired by population games reduces grid consumption by 12% when compared to the traditional best-signal-level association policy.Peer ReviewedPostprint (author's final draft

Atomicity and non-anonymity in population-like games for the energy efficiency of hybrid-power HetNets

© 2018 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.In this paper, the user–base station (BS) association problem is addressed to reduce grid consumption in heterogeneous cellular networks (HetNets) powered by hybrid energy sources (grid and renewable energy). The paper proposes a novel distributed control scheme inspired by population games and designed considering both atomicity and non-anonymity – i.e., describing the individual decisions of each agent. The controller performance is considered from an energy–efficiency perspective, which requires the guarantee of appropriate qualityof-service (QoS) levels according to renewable energy availability. The efficiency of the proposed scheme is compared with other heuristic and optimal alternatives in two simulation scenarios. Simulation results show that the proposed approach inspired by population games reduces grid consumption by 12% when compared to the traditional best-signal-level association policy.Peer ReviewedPostprint (author's final draft

A Coalitional Model Predictive Control for the Energy Efficiency of Next-Generation Cellular Networks

Next-generation cellular networks are large-scale systems composed of numerous base stations interacting with many diverse users. One of the main challenges with these networks is their high energy consumption due to the expected number of connected devices. We handle this issue with a coalitional Model Predictive Control (MPC) technique for the case of next-generation cellular networks powered by renewable energy sources. The proposed coalitional MPC approach is applied to two simulated scenarios and compared with other control methods: the traditional best-signal level mechanism, a heuristic algorithm, and decentralized and centralized MPC schemes. The success of the coalitional strategy is considered from an energy efficiency perspective, which means reducing on-grid consumption and improving network performance (e.g., number of users served and transmission rates)

A Coalitional Model Predictive Control Approach for Heterogeneous Cellular Networks

Heterogeneous cellular networks (HetNets) are large-scale systems that comprise numerous base stations interacting with a significant number of users of diverse types. Finding a trade-off between energy consumption and quality of service is one of the major challenges in these networks. To deal with this issue, a coalitional model predictive control (MPC) approach is proposed for a HetNet powered by renewable power sources, and compared in simulation with the traditional best-signal level mechanism and the centralized MPC method. Furthermore, other key performance indicators associated with grid consumption such as the number of served users and transmission rates are also evaluated

Modificación experimental de la técnica de membrana inducida (Masquelet) mediante uso de medios condicionados producidos por células madre mesenquimales

INTRODUCCIÓN: La reconstrucción de defectos óseos segmentarios en huesos largos continúa siendo un reto para el cirujano ortopedista, y las técnicas quirúrgicas disponibles tienen múltiples limitaciones. La técnica de reconstrucción en dos tiempos a través de la inducción de membrana descrita por el Dr. Alain Masquelet aún está en desarrollo y una de sus limitaciones radica en el volumen del injerto óseo. El objetivo del presente trabajo es evaluar mediante un modelo animal experimental la utilización de medios condicionados, productos de la secreción paracrina de células madre mesenquimales (MSC), como alternativa al uso de injerto óseo en el segundo tiempo quirúrgico de la técnica y, estudiar los aspectos biológicos de la expansión y diferenciación de las células madre mesenquimales in vivo en la búsqueda de estrategias terapéuticas para el tratamiento de defectos óseos estructurales en huesos largos. MATERIALES Y METODOS: Estudio experimental en modelo animal. 9 Conejos en los cuales se reprodujo la técnica de membrana inducida posterior a la creación de un defecto óseo de 1 cm en la diáfisis femoral. Durante la primera intervención se realizó estabilización de la osteotomía con un fijador externo diseñado para la especie animal y colocación de polimetilmetacrilato (PMMC) en el área del defecto óseo. Durante el segundo tiempo quirúrgico se dividieron los animales en cuatro grupos para evaluar el efecto paracrino de la MSC y su expansión y diferenciación celular. Se realizó evaluación radiológica 4 semanas posterior a la intervención y se compararon los hallazgos entre los diferentes grupos en relación al porcentaje de cierre del defecto óseo. RESULTADOS: En todos los grupos se confirmó la capacidad osteoinductora de la membrana en ausencia de injerto óseo; esta capacidad se aumenta mediante el uso de medios condicionados derivados de cultivos der MSC, logrando un 98% de cierre del defecto óseo. DISCUSIÓN: Es posible la utilización de medios condicionados producidos por células madre mesenquimales, basado en su efecto paracrino, como alternativa al injerto óseo durante el segundo tiempo quirúrgico en la técnica de Masquelet en conejos, para el tratamiento de defectos óseos en huesos largos. De esta forma, se plantea una alternativa para el tratamiento de defectos óseos en huesos largos y posible modificación de la técnica de Masquelet.Abstract. INTRODUCTION: Reconstruction of segmental defects in long bones remains a challenge for the orthopedic surgeon and surgical techniques available have many limitations. The two times reconstruction technique through induction of membrane described by Dr. Alain Masquelet is still in development and one of its limitations lies in the volume of bone graft. The aim of this study is to evaluate in an experimental animal model the use of conditioned media, products of paracrine secretion of mesenchymal stem cells (MSC) as an alternative to bone graft in the second surgical time and study the biological aspects of the expansion and differentiation of MSC in vivo in the search for therapeutic options for the treatment of structural bone defects in long bones strategies. MATERIALS AND METHODS: Experimental study on animal model. 9 rabbits in which the technique of induced membrane was reproduced later of a creation of a bony defect of 1 cm in the femoral shaft. During the first intervention the stabilization of the osteotomy was performed with an external fixator designed for this animal specie and placement of polymethylmethacrylate (PMMC) in the area of the bone defect. During the second operation the animals were divided into four groups to evaluate the paracrine effect of the MSC and their expansion and differentiation. Radiological evaluation was performed 4 weeks after the intervention and the findings between different groups were compared on the percentage bone defect closure. RESULTS : In all groups, the osteoinductive capability of the membrane in the absence of bone graft is confirmed; this capacity is increased by the use of conditioned media derived from a MSC cultive , achieving a 98 % closure of the bone defect. DISCUSSION : It is possible using conditioned media produced by mesenchymal stem cells based on its paracrine effect, as an alternative to bone graft during the second procedure in the Masquelet technique in rabbits, for treating bone defects in long bones . The conditioned media are an alternative for the treatment of long bone defects and possible modification of the Masquelet technique.Otr

Control Strategies for Energy Efficiency of Next-generation Cellular Networks with Hybrid Energy Sources

Large-scale systems are characterised by having a large number of components working in coordination. These systems can be composed of geographically distributed elements with resource limitations. In this way, control strategies for large-scale systems have challenges related to information flow, processing time and capacity, controller design, and energyresource optimisation. One particular large-scale system is the next-generation mobile communications cellular network, which will comprise hundreds of base stations interacting with thousands of users in milliseconds. One of the main challenges with next-generation cellular networks (NGCNs) is the higher energy consumption caused by the expected number of connected devices. Here, renewable energies are a good option to face the growing demand of energy consumption. However, there are still major challenges related to the appropriate control schemes to minimise ongrid consumption and optimise energy management in cellular networks with hybrid energy sources (grid and renewable energy). In this thesis, different control strategies for large-scale networks are proposed. These control strategies are assessed over an NGCN powered by hybrid energy sources to reduce grid consumption. The energy-efficiency problem is studied from the viewpoint of the energetic processes – i.e., on-place renewable energy is available, and mechanisms to reduce the gridenergy consumption should be developed. The proposed mechanisms are based on previous research that shows the relationship between the number of users connected to a cellular network base station (BS) and its energy consumption. For this reason, the study of optimal control mechanisms that balance the load of users over the available BSs according to the renewable energy available is a key element in the field of energy efficiency in cellular networks. These schemes are assessed through simulations and then compared with the scheme actually used to manage the user–BS association in cellular networks. The results show that the proposed control schemes improve grid-electricity consumption compared with the traditional association mechanism while still maintaining adequate quality-of-service (QoS) levels. The control schemes for the energy-efficiency problem were studied in two timescales. The short timescale (of the order of seconds) was used to analyse the user–BS association problem in a network configuration with hybrid power sources without an energy storage system. The long timescale (of the order of hours) was used to study load balancing of aggregated traffic in each BS with hybrid power sources and an energy storage system. Finally, the proposed controllers are of different types: (i) centralised, (ii) distributed at the base-station level, and (iii) distributed at the user levelResumen: Los sistemas de gran escala se caracterizan por tener un gran n´umero de componentes trabajando de forma coordinada. Estos sistemas est´an conformados por elementos que pueden estar distribuidos a lo largo de una extensa ´area geogr´afica y poseer restricciones en cuanto a la disponibilidad de recursos necesarios para su funcionamiento. Teniendo en cuenta estas caracter´ısticas, las estrategias de control para sistemas de gran escala presentan retos relacionados con el flujo de la informaci´on, la capacidad y tiempo de procesamiento, el dise˜no de los controladores y la optimizaci´on de los recursos disponibles. Un tipo particular de sistema de gran escala son las redes de comunicaci´on m´ovil celular de pr´oxima generaci´on, que se encontrar´an conformadas por cientos de estaciones base que interactuar´an con miles de usuarios en instantes de tiempo del orden de los milisegundos. Uno de los principales desaf´ıos en las redes celulares de pr´oxima generaci´on (RCPG) es el incremento en el consumo energ´etico causado por el crecimiento esperado de dispositivos conectados. En este contexto, las energ´ıas renovables son una buena alternativa para afrontar la creciente demanda de consumo energ´etico. Sin embargo, existen importantes desaf´ıos relacionados con los esquemas de control adecuados para minimizar el consumo de energ´ıa proveniente de la red el´ectrica convencional (grid) y optimizar la gesti´on energ´etica en redes celulares con fuentes de alimentaci´on h´ıbrida (grid y renovable). En esta tesis, se proponen y eval´uan diferentes estrategias de control para redes de gran escala, utilizando como caso de estudio las RCPG alimentadas con fuentes h´ıbridas y su objetivo de reducir el consumo grid. El problema de la eficiencia energ´etica es estudiado desde el punto de vista de los procesos energ´eticos, es decir, de la disponibilidad de energ´ıa renovable en el emplazamiento del sistema y los mecanismos para reducir el consumo energ´etico. Los mecanismos propuestos se basan en investigaciones previas que demostraron la relaci´on existente entre el n´umero de usuarios conectados a las estaciones base (EB) de la red y su consumo energ´etico. Por esta raz´on, el estudio de mecanismos de control ´optimo que balanceen la carga de tr´afico sobre las EB de acuerdo con la energ´ıa renovable disponible es un elemento clave en el campo de la eficiencia energ´etica en redes celulares. Estos esquemas son evaluados a trav´es de simulaciones y comparados con el mecanismo usado actualmente por las redes celulares para gestionar la asociaci´on de los usuarios a las EB. Los resultados de la tesis muestran que los esquemas de control propuestos mejoran el consumo grid comparado con el mecanismo de asociaci´on tradicional a la vez que mantienen adecuados niveles de calidad del servicio. Los esquemas de control para el problema de la eficiencia energ´etica fueron estudiados en dos escalas de tiempo. La corta escala de tiempo (del orden de los segundos) fue usada para analizar el problema de la asociaci´on de los usuarios a las EB en una configuraci´on de red con fuentes de potencia h´ıbridas y sin sistema de almacenamiento energ´etico. La larga escala de tiempo (del orden de horas) fue utilizada para estudiar el balanceo de carga de tr´afico agregado en cada EB, con fuentes h´ıbridas de potencia y con sistema de almacenamiento energ´etico. Finalmente, los controladores desarrollados son de diferentes tipos: i) esquema centralizado, ii) esquemas distribuidos a nivel de usuario y iii) esquemas distribuidos a nivel de estaciones base.Doctorad

Simulation of delay in data transmission in a cellular network due to Handoff

RESUMEN: El presente artículo presenta el resultado de la simulación numérica del efecto de la velocidad de un dispositivo móvil en el retraso de la transmisión de datos en una red celular debido a Handoff. La generación del código y realización de las simulaciones se hizo por medio del entorno integrado de desarrollo Matlab. Como resultado se analizaron las respuestas del sistema de red celular al variar los parámetros de velocidad del dispositivo móvil y tiempo de realización de la prueba, y se obtuvo un modelo del sistema planteado que permite determinar el retraso en función de estos dos parámetros.ABSTRACT: This paper presents the outputs of numerical simulation of the effect of a mobile device's speed in delay of data transmission in a cellular network, because of Handoff. Code generation and simulations was done using Matlab's development environment. As a result, the responses of cellular network system by varying the parameters of mobile speed and time of completion of the test were analysed, and a model of the proposed system for determining the delay based on these two parameters was obtained

Simulación del retraso en la transmisión de datos en una red celular debido al Handoff

This paper presents the outputs of numerical simulation of the effect of a mobile device's speed in delay of data transmission in a cellular network, because of Handoff. Code generation and simulations was done using Matlab's development environment. As a result, the responses of cellular network system by varying the parameters of mobile speed and time of completion of the test were analysed, and a model of the proposed system for determining the delay based on these two parameters was obtained.El presente artículo presenta el resultado de la simulación numérica del efecto de la velocidad de un dispositivo móvil en el retraso de la transmisión de datos en una red celular debido a Handoff. La generación del código y realización de las simulaciones se hizo por medio del entorno integrado de desarrollo Matlab. Como resultado se analizaron las respuestas del sistema de red celular al variar los parámetros de velocidad del dispositivo móvil y tiempo de realización de la prueba, y se obtuvo un modelo del sistema planteado que permite determinar el retraso en función de estos dos parámetros

La Inteligencia Artificial como apoyo a la gestión de la seguridad ciudadana: un estado del arte

Cada vez más, existe un mayor interés en los gobiernos de múltiples ciudades de garantizar la seguridad de sus ciudadanos, siendo la tecnología una de las herramientas clave para enfrentar los diferentes retos que en este campo se plantean. En este trabajo se presenta una aproximación al estado del arte de algoritmos estadísticos y técnicas de inteligencia computacional utilizados en el campo de la gestión de problemas de seguridad ciudadana. Para esto se escogieron dos de las aplicaciones más relevantes en el área, las cuales son: detección de disparos y detección de armas. Para cada una de estas aplicaciones se hizo un cuadro con los trabajos más relevantes junto con un posterior análisis, se formularon las conclusiones y se describió el trabajo futuro. Finalmente, se organizó una lista de recomendaciones con los algoritmos más utilizados y que mejores resultados han arrojadoIncreasingly, there is a greater interest in the governments of multiple cities to guarantee the safety of their citizens, technology being one of the main tools to face the different challenges that arise in this field. This paper presents an approach to the state of the art of statistical algorithms and computational intelligence techniques used to manage some citizen security problems. For this, we studied two of the most relevant applications in the area: detection of shots and detection of weapons. For each application, a resume of the main works is presented, followed by an analysis, conclusions, and future work. Finally, it is presented a list of recommendations with the most used algorithms and those with the best result