42 research outputs found
Distributed algorithms for localization in Wireless Sensor Networks
We introduce the concept of localization in Wireless Sensor Networks, starting from ranging measurements available at sensor nodes. We explore different solutions available in the literature and then we introduce the algorithms proposed by two recent publications. Finally, we propose a new hybrid ADMM algorithm that, considering both the original non-convex problem and a convexification of the problem, allows to obtain better performancesope
Network resource allocation policies with energy transfer capabilities
During the last decades, mobile network operators have witnessed an exponential increase in the traffic demand, mainly due to the high request of services from a huge amount of users. The trend is of a further increase in both the traffic demand and the number of connected devices over the next years. The traffic load is expected to have an annual growth rate of 53% for the mobile network alone, and the upcoming industrial era, which will connect different types of devices to the mobile infrastructure including human and machine type communications, will definitely exacerbate such an increasing trend.
The current directions anticipate that future mobile networks will be composed of ultra dense deployments of heterogeneous Base Stations (BSs), where BSs using different transmission powers coexist. Accordingly, the traditional Macro BSs layer will be complemented or replaced with multiple overlapping tiers of small BSs (SBSs), which will allow extending the system capacity. However, the massive use of Information and Communication Technology (ICT) and the dense deployment of network elements is going to increase the level of energy consumed by the telecommunication infrastructure and its carbon footprint on the environment.
Current estimations indicates that 10% of the worldwide electricity generation is due to the ICT industry and this value is forecasted to reach 51% by 2030, which imply that 23% of the carbon footprint by human activity will be due to ICT. Environmental sustainability is thus a key requirement for designing next generation mobile networks.
Recently, the use of Renewable Energy Sources (RESs) for supplying network elements has attracted the attention of the research community, where the interest is driven by the increased efficiency and the reduced costs of energy harvesters and storage devices, specially when installed to supply SBSs. Such a solution has been demonstrated to be environmentally and economically sustainable in both rural and urban areas. However, RESs will entail a higher management complexity. In fact, environmental energy is inherently erratic and intermittent, which may cause a
fluctuating energy inflow and produce service outage. A proper control of how the energy is drained and balanced across network elements is therefore necessary for a self-sustainable network design.
In this dissertation, we focus on energy harvested through solar panels that is deemed the most appropriate due to the good efficiency of commercial photovoltaic panels as well as the wide availability of the solar source for typical installations. The characteristics of this energy source are analyzed in the first technical part of the dissertation, by considering an approach based on the extraction of features from collected data of solar energy radiation.
In the second technical part of the thesis we introduce our proposed scenario. A federation of BSs together with the distributed harvesters and storage devices at the SBS sites form a micro-grid, whose operations are managed by an energy management system in charge of controlling the intermittent and erratic energy budget from the RESs. We consider load control (i.e., enabling sleep mode in the SBSs) as a method to properly manage energy inflow and spending, based on the traffic demand. Moreover, in the third technical part, we introduce the possibility of improving the network energy efficiency by sharing the exceeding energy that may be available at some BS sites within the micro-grid.
Finally, a centralized controller based on supervised and reinforcement learning is proposed in the last technical part of the dissertation. The controller is in charge of opportunistically operating the network to achieve efficient utilization of the harvested energy and prevent SBSs blackout.Durante las últimas décadas, los operadores de redes móviles han sido testigos de un aumento exponencial en la demanda de tráfico, principalmente debido a la gran solicitud de servicios de una gran cantidad de usuarios. La tendencia es un aumento adicional tanto en la demanda de tráfico como en la cantidad de dispositivos conectados en los próximos años. Se espera que la carga de tráfico tenga una tasa de crecimiento anual del 53% solo para la red móvil, y la próxima era industrial, que conectará diferentes tipos de dispositivos a la infraestructura móvil, definitivamente exacerbará tal aumento. Las instrucciones actuales anticipan que las redes móviles futuras estarán compuestas por despliegues ultra densos de estaciones base (BS) heterogéneas. En consecuencia, la capa tradicional de Macro BS se complementará o reemplazará con múltiples niveles superpuestos de pequeños BS (SBS), lo que permitirá ampliar la capacidad del sistema. Sin embargo, el uso masivo de la Tecnología de la Información y la Comunicación (TIC) y el despliegue denso de los elementos de la red aumentará el nivel de energía consumida por la infraestructura de telecomunicaciones y su huella de carbono en el medio ambiente. Las estimaciones actuales indican que el 10% de la generación mundial de electricidad se debe a la industria de las TIC y se prevé que este valor alcance el 51% para 2030, lo que implica que el 23% de la huella de carbono por actividad humana se deberá a las TIC. La sostenibilidad ambiental es, por lo tanto, un requisito clave para diseñar redes móviles de próxima generación. Recientemente, el uso de fuentes de energía renovables (RES) para suministrar elementos de red ha atraído la atención de la comunidad investigadora, donde el interés se ve impulsado por el aumento de la eficiencia y la reducción de los costos de los recolectores y dispositivos de almacenamiento de energía, especialmente cuando se instalan para suministrar SBS. Se ha demostrado que dicha solución es ambiental y económicamente sostenible tanto en áreas rurales como urbanas. Sin embargo, las RES conllevarán una mayor complejidad de gestión. De hecho, la energía ambiental es inherentemente errática e intermitente, lo que puede causar una entrada de energía fluctuante y producir una interrupción del servicio. Por lo tanto, es necesario un control adecuado de cómo se drena y equilibra la energía entre los elementos de la red para un diseño de red autosostenible. En esta disertación, nos enfocamos en la energía cosechada a través de paneles solares que se considera la más apropiada debido a la buena eficiencia de los paneles fotovoltaicos comerciales, así como a la amplia disponibilidad de la fuente solar para instalaciones típicas. Las características de esta fuente de energía se analizan en la primera parte técnica de la disertación, al considerar un enfoque basado en la extracción de características de los datos recopilados de radiación de energía solar. En la segunda parte técnica de la tesis presentamos nuestro escenario propuesto. Una federación de BS junto con los cosechadores distribuidos y los dispositivos de almacenamiento forman una microrred, cuyas operaciones son administradas por un sistema de administración de energía a cargo de controlar el presupuesto de energía intermitente y errático de las RES. Consideramos el control de carga como un método para administrar adecuadamente la entrada y el gasto de energía, en función de la demanda de tráfico. Además, en la tercera parte técnica, presentamos la posibilidad de mejorar la eficiencia energética de la red al compartir la energía excedente que puede estar disponible en algunos sitios dentro de la microrred. Finalmente, se propone un controlador centralizado basado en aprendizaje supervisado y de refuerzo en la última parte técnica de la disertación. El controlador está a cargo de operar la red para lograr una utilización eficiente de energía y previene el apagón de SB
Data analytics for smart parking applications
We consider real-life smart parking systems where parking lot occupancy data are collected from field sensor devices and sent to backend servers for further processing and usage for applications. Our objective is to make these data useful to end users, such as parking managers, and, ultimately, to citizens. To this end, we concoct and validate an automated classification algorithm having two objectives: (1) outlier detection: to detect sensors with anomalous behavioral patterns, i.e., outliers; and (2) clustering: to group the parking sensors exhibiting similar patterns into distinct clusters. We first analyze the statistics of real parking data, obtaining suitable simulation models for parking traces. We then consider a simple classification algorithm based on the empirical complementary distribution function of occupancy times and show its limitations. Hence, we design a more sophisticated algorithm exploiting unsupervised learning techniques (self-organizing maps). These are tuned following a supervised approach using our trace generator and are compared against other clustering schemes, namely expectation maximization, k-means clustering and DBSCAN, considering six months of data from a real sensor deployment. Our approach is found to be superior in terms of classification accuracy, while also being capable of identifying all of the outliers in the dataset
Large Language Models for Telecom: Forthcoming Impact on the Industry
Large Language Models (LLMs), AI-driven models that can achieve
general-purpose language understanding and generation, have emerged as a
transformative force, revolutionizing fields well beyond Natural Language
Processing (NLP) and garnering unprecedented attention. As LLM technology
continues to progress, the telecom industry is facing the prospect of its
impact on its landscape. To elucidate these implications, we delve into the
inner workings of LLMs, providing insights into their current capabilities and
limitations. We also examine the use cases that can be readily implemented in
the telecom industry, streamlining tasks, such as anomalies resolutions and
technical specifications comprehension, which currently hinder operational
efficiency and demand significant manpower and expertise. Furthermore, we
uncover essential research directions that deal with the distinctive challenges
of utilizing the LLMs within the telecom domain. Addressing them represents a
significant stride towards fully harnessing the potential of LLMs and unlocking
their capabilities to the fullest extent within the telecom domain
Energy sustainable paradigms and methods for future mobile networks: A survey
In this survey, we discuss the role of energy in the design of future mobile
networks and, in particular, we advocate and elaborate on the use of energy
harvesting (EH) hardware as a means to decrease the environmental footprint of
5G technology. To take full advantage of the harvested (renewable) energy,
while still meeting the quality of service required by dense 5G deployments,
suitable management techniques are here reviewed, highlighting the open issues
that are still to be solved to provide eco-friendly and cost-effective mobile
architectures. Several solutions have recently been proposed to tackle
capacity, coverage and efficiency problems, including: C-RAN, Software Defined
Networking (SDN) and fog computing, among others. However, these are not
explicitly tailored to increase the energy efficiency of networks featuring
renewable energy sources, and have the following limitations: (i) their energy
savings are in many cases still insufficient and (ii) they do not consider
network elements possessing energy harvesting capabilities. In this paper, we
systematically review existing energy sustainable paradigms and methods to
address points (i) and (ii), discussing how these can be exploited to obtain
highly efficient, energy self-sufficient and high capacity networks. Several
open issues have emerged from our review, ranging from the need for accurate
energy, transmission and consumption models, to the lack of accurate data
traffic profiles, to the use of power transfer, energy cooperation and energy
trading techniques. These challenges are here discussed along with some
research directions to follow for achieving sustainable 5G systems.Comment: Accepted by Elsevier Computer Communications, 21 pages, 9 figure
Rate, Power, and Energy Efficiency Trade-Offs in Massive MIMO Systems With Carrier Aggregation
[EN] This work considers a multi-cell, multi-carrier massive MIMO network with carrier aggregation capabilities, and tackles both the rate versus power consumption and the rate versus energy efficiency (EE) trade-offs, by jointly optimizing the number of employed carriers, transmit antennas, base station density, and transmit power. Provably convergent algorithms for both trade-off problems are developed, together with closed-form results for the individual optimization of the considered resources, taking three main carrier aggregation techniques into account, namely inter-carrier, intra-carrier contiguous, and intra-carrier non-contiguous. Numerical results show how the use of carrier aggregation represents an effective way of increasing the network rate and EE, while keeping the power consumption at bay. By using carrier aggregation, it is possible to reduce the number of deployed antennas, without sacrificing the rate performance and increasing the system EE.This work was supported by the Generalitat Valenciana,Spain, through the CIDEGENT PlaGenT under Grant CIDEXG/2022/17,and Project iTENTE. The work of Alessio Zappone was supported by the Italian Ministry of Research through the Program "Dipartimenti di Eccellenza2018-2022."Zappone, A.; López-Pérez, D.; De Domenico, A.; Piovesan, N.; Bao, H. (2023). Rate, Power, and Energy Efficiency Trade-Offs in Massive MIMO Systems With Carrier Aggregation. IEEE Transactions on Green Communications and Networking. 7(3):1342-1355. https://doi.org/10.1109/TGCN.2023.3275302134213557
UMA ABORDAGEM ETNOMATEMÁTICA DO PERFIL DO PROFESSOR DE MATEMÁTICA, DAS ESCOLAS INDÍGENAS, DA REGIÃO NOROESTE DO RIO GRANDE DO SUL
Sabe-se que a visão sobre a matemática ensinada nas aldeias indígenas é diferente das ensinadas nas escolas regulares. Neste sentido, o trabalho da etnomatemática ao dialogar com os povos indígenas, é o de fazer com que valorizem cada vez mais sua cultura, reconhecendo suas construções e suas produções e evitando conflitos culturais que resultam da introdução da ‘matemática do branco’ na educação indígena. Desta forma, o presente artigo busca caracterizar o processo de ensino-aprendizagem de matemática, na educação escolar indígena,das diferentes reservas da região noroeste do estado do Rio Grande do Sul, sob o olhar da etnomatemática, destacando, o perfil do professor. Foram realizadas entrevistas com seis professores de matemática das escolas indígenas de Iraí, Liberato Salzano e Planalto. Muitas são as dificuldades apresentadas no ensino de matemática nas escolas indígenas e, quando questionados, os professores relataram diversas. Além dos conteúdos, foram destacadas outras dificuldades como influência da mídia, falta de concentração dos alunos e antipatia com a disciplina. Destaca-se a grande importância desta pesquisa para a comunidade em geral, onde passa-se a ter conhecimento a respeito da vida profissional dos professores das escolas indígenas, no que diz respeito a matemática, bem como em relação ao perfil deste profissional
TeleQnA: A Benchmark Dataset to Assess Large Language Models Telecommunications Knowledge
We introduce TeleQnA, the first benchmark dataset designed to evaluate the
knowledge of Large Language Models (LLMs) in telecommunications. Comprising
10,000 questions and answers, this dataset draws from diverse sources,
including standards and research articles. This paper outlines the automated
question generation framework responsible for creating this dataset, along with
how human input was integrated at various stages to ensure the quality of the
questions. Afterwards, using the provided dataset, an evaluation is conducted
to assess the capabilities of LLMs, including GPT-3.5 and GPT-4. The results
highlight that these models struggle with complex standards related questions
but exhibit proficiency in addressing general telecom-related inquiries.
Additionally, our results showcase how incorporating telecom knowledge context
significantly enhances their performance, thus shedding light on the need for a
specialized telecom foundation model. Finally, the dataset is shared with
active telecom professionals, whose performance is subsequently benchmarked
against that of the LLMs. The findings illustrate that LLMs can rival the
performance of active professionals in telecom knowledge, thanks to their
capacity to process vast amounts of information, underscoring the potential of
LLMs within this domain. The dataset has been made publicly accessible on
GitHub
Effect of Binding Modules Fused to Cutinase on the Enzymatic Synthesis of Polyesters
open9In relation to the development of environmentally-friendly processing technologies for the continuously growing market of plastics, enzymes play an important role as green and sustainable biocatalysts. The present study reports the use of heterogeneous immobilized biocatalysts in solvent-free systems for the synthesis of aliphatic oligoesters with Mws and monomer conversions up to 1500 Da and 74%, respectively. To improve the accessibility of hydrophilic and hydrophobic substrates to the surface of the biocatalyst and improve the reaction kinetic and the chain elongation, two different binding modules were fused on the surface of cutinase 1 from Thermobifida cellulosilytica. The fusion enzymes were successfully immobilized (>99% of bound protein) via covalent bonding onto epoxy-activated beads. To the best of our knowledge, this is the first example where fused enzymes are used to catalyze transesterification reactions for polymer synthesis purposes.openFerrario, Valerio; Todea, Anamaria; Wolansky, Lisa; Piovesan, Nicola; Guarneri, Alice; Ribitsch, Doris; Guebitz, Georg M.; Gardossi, Lucia; Pellis, AlessandroFerrario, Valerio; Todea, Anamaria; Wolansky, Lisa; Piovesan, Nicola; Guarneri, Alice; Ribitsch, Doris; Guebitz, Georg M.; Gardossi, Lucia; Pellis, Alessandr