420 research outputs found
Learning-based tracking area list management in 4G and 5G networks
© 2020 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 worksMobility management in 5G networks is a very challenging issue. It requires novel ideas and improved management so that signaling is kept minimized and far from congesting the network. Mobile networks have become massive generators of data and in the forthcoming years this data is expected to increase drastically. The use of intelligence and analytics based on big data is a good ally for operators to enhance operational efficiency and provide individualized services. This work proposes to exploit User Equipment (UE) patterns and hidden relationships from geo-spatial time series to minimize signaling due to idle mode mobility. We propose a holistic methodology to generate optimized Tracking Area Lists (TALs) in a per UE manner, considering its learned individual behavior. The k -means algorithm is proposed to find the allocation of cells into tracking areas. This is used as a basis for the TALs optimization itself, which follows a combined multi-objective and single-objective approach depending on the UE behavior. The last stage identifies UE profiles and performs the allocation of the TAL by using a neural network. The goodness of each technique has been evaluated individually and jointly under very realistic conditions and different situations. Results demonstrate important signaling reductions and good sensitivity to changing conditions.This work was supported by the Spanish National Science Council and ERFD funds under projects TEC2014-60258-C2-2-R and RTI2018-099880-B-C32.Peer ReviewedPostprint (author's final draft
A Novel Multiobjective Cell Switch-Off Framework for Cellular Networks
Cell Switch-Off (CSO) is recognized as a promising approach to reduce the
energy consumption in next-generation cellular networks. However, CSO poses
serious challenges not only from the resource allocation perspective but also
from the implementation point of view. Indeed, CSO represents a difficult
optimization problem due to its NP-complete nature. Moreover, there are a
number of important practical limitations in the implementation of CSO schemes,
such as the need for minimizing the real-time complexity and the number of
on-off/off-on transitions and CSO-induced handovers. This article introduces a
novel approach to CSO based on multiobjective optimization that makes use of
the statistical description of the service demand (known by operators). In
addition, downlink and uplink coverage criteria are included and a comparative
analysis between different models to characterize intercell interference is
also presented to shed light on their impact on CSO. The framework
distinguishes itself from other proposals in two ways: 1) The number of
on-off/off-on transitions as well as handovers are minimized, and 2) the
computationally-heavy part of the algorithm is executed offline, which makes
its implementation feasible. The results show that the proposed scheme achieves
substantial energy savings in small cell deployments where service demand is
not uniformly distributed, without compromising the Quality-of-Service (QoS) or
requiring heavy real-time processing
Energy saving scheme for multicarrier HSPA + under realistic traffic fluctuation
The final publication is available at Springer via http://dx.doi.org/10.1007/s11036-015-0656-6In the near future, an increase in cellular network density is expected to be one of the main enablers to boost the system capacity. This development will lead to an increase in the network energy consumption. In this context, we propose an energy efficient dynamic scheme for HSDPA + (High Speed Downlink Packet Access-Advanced) systems aggregating several carriers and which adapts dynamically to the network traffic. The scheme evaluates whether node-B deactivation is feasible without compromising the user flow throughput. Furthermore, instead of progressive de-activation of carriers and/or node-B switch-off, we evaluate the approach where feasible combination of inter-site distance and number of carriers is searched to obtain best savings. This is done by also considering the effect of transition delays between network configuration changes. The solution exploits the fact that re-activation of carriers might permit turning off other BSs earlier at relatively higher load than existing policies. Remote electrical downtilt is also considered as a means to maximize the utilization of higher modulation and coding schemes in the extended cells. This approach promises significant energy savings when compared with existing policies - not only for low traffic hours but also for medium load scenarios.Peer ReviewedPostprint (author's final draft
Automatic Link Balancing Using Fuzzy Logic Control of Handover Parameter
Postprint (published version
Automatic Link Balancing Using Fuzzy Logic Control of Handover Parameter
Postprint (published version
Spot electoral: estrategia de visualizaciĂłn de candidatos en las campañas polĂticas
They describe the electoral spot as a "compressed communication format, the main audiovisual communication space between the electorate and political parties", it is loaded with persuasive political marketing techniques that seeks to generate a certain capacity for influence (negative or positive) on the electorate . The advertising piece has also been defined by scholars of political communication as video politics.
This article shows the use of the spot in electoral campaigns, from some pieces of candidates for the presidency in Colombia, during the nineties and the beginning of the new millennium, also opponents of the 2014 Colombian Congress, especially in the department of Boyacá. Also in the elective process to the Congress of the Republic 2018, there the applicants for Boyacá consolidate the use of Information and Communication Technologies-Tic to achieve the visualization of their spots. Some theoretical elements developed obey the terms electoral media ecosystem; the stories that manage to be told in the videos, based on seven communicative codes: linguistic language; kinesic language; proxemic language; iridological language; physiological language; fashion; and nonverbal voice values. The work is the product of the completed project Electoral behavior in Boyacá 2018: from the Congress of the Republic and Presidential contests, which analyzed the electoral behavior in Boyacá, from the Congress of the Republic and Presidential contests.El spot electoral lo describen como “formato comunicacional comprimido, el principal espacio de comunicaciĂłn audiovisual entre el electorado y los partidos polĂticos”, este viene cargado de tĂ©cnicas persuasivas de mercadeo polĂtico que busca generar cierta capacidad de influencia (negativa o positiva) sobre el electorado. La pieza publicitaria tambiĂ©n ha sido definida por estudiosos de la comunicaciĂłn polĂtica como la videopolĂtica.
El presente artĂculo muestra el uso del spot en las campañas electorales, desde algunas piezas de candidatos a la presidencia en Colombia, durante los años noventa e inicios del nuevo milenio, asimismo contrincantes al Congreso colombiano 2014, especialmente en el departamento de Boyacá. TambiĂ©n en el proceso electivo al Congreso de la RepĂşblica 2018, allĂ los aspirantes por Boyacá consolidan el uso de las TecnologĂas de la InformaciĂłn y ComunicaciĂłn-Tic para lograr la visualizaciĂłn de sus spots. Algunos elementos teĂłricos desarrollados obedecen a los tĂ©rminos ecosistema mediático electoral; las historias que logran ser contadas en los videos, basadas en siete cĂłdigos comunicativos: lenguaje lingĂĽĂstico; lenguaje kinĂ©sico; lenguaje proxĂ©mico; lenguaje iridolĂłgico; lenguaje fisiolĂłgico; moda; y valores no verbales voz. El trabajo es producto del proyecto finalizado Comportamiento electoral en Boyacá 2018: desde las contiendas Congreso de la RepĂşblica y Presidencial, el cual analizĂł el comportamiento electoral en Boyacá, desde las contiendas Congreso de la RepĂşblica y Presidencial
Mutual accords: formulae for twenty-one years of military and bipartisan dictatorships in Colombia, 1953 - 1974
En el presente artĂculo se abordan las acciones de lucha por el poder que establecen
directamente las Ă©lites polĂticas o clase burguesa colombiana entre los años
cincuenta al setenta del siglo pasado, con el fin de conseguir su reacomodamiento
ante las circunstancias ligadas al gobierno militar encabezado por el general
Gustavo Rojas Pinilla. Se generĂł un acuerdo llamado el Frente Nacional, fĂłrmula
“salvadora de paz” que teóricamente se articula con los términos dictadura y consociacionalismo,
variables cualitativas que desencadenaron residuos polĂticos de
algunos hechos de polarizaciĂłn y violencia en el paĂs que son materializados en la
actualidad.This paper sets out the customary actions regarding power struggle that political
élites and the Colombian bourgeoisie undertook between the 50’s and 60’s in
order to restore the position they held before General Gustavo Rojas Pinilla’s coup
d’état and subsequent military dictatorship. For that, a common agreement known
as Frente Nacional (National Front) was created. It was a “peace granting” formula
which, in theory, articulated dictatorship terms and consociationalism; these
qualitative variables unleashed political remnants from some polarization and
violence incidents in the country that still have consequences today
The Role of Vitamin C in the Protection and Modulation of Genotoxic Damage Induced by Metals Associated with Oxidative Stress
This chapter reviews the effects of vitamin C on metal-induced genotoxicity. By focusing on cutting-edge studies, including our own results in experiments with vanadium(V) and chromium(VI), the suggestion that vitamin C can be used effectively to protect against or reduce the genotoxic effects induced by metal exposure by suppressing oxidative stress is particularly explored. After explaining the chemical mechanisms involved in oxidative stress associated with heavy metals, this chapter discusses the various proposals regarding the physiological processes of vitamin C at the molecular level, its relationship with oxidative stress, levels of 8-hydroxydeoxyguanosine (8-OH-dG, 7,8-dihy-dro-8-oxodeoxyguanosine) and apoptosis, and its role in the protection and modulation of DNA damage, as well as how they fit with our own results that showed an increase in apoptosis and 8-OH-dG when vitamin C was administered in addition to the metallic compounds. The relevant gaps in our understanding of the role of vitamin C with regard to these issues are highlighted, as well as the key importance of its clinical use, and ultimately, human health
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