222 research outputs found

    Advances in Computer Science and Engineering

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    The book Advances in Computer Science and Engineering constitutes the revised selection of 23 chapters written by scientists and researchers from all over the world. The chapters cover topics in the scientific fields of Applied Computing Techniques, Innovations in Mechanical Engineering, Electrical Engineering and Applications and Advances in Applied Modeling

    Wi-Fi based people tracking in challenging environments

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    People tracking is a key building block in many applications such as abnormal activity detection, gesture recognition, and elderly persons monitoring. Video-based systems have many limitations making them ineffective in many situations. Wi-Fi provides an easily accessible source of opportunity for people tracking that does not have the limitations of video-based systems. The system will detect, localise, and track people, based on the available Wi-Fi signals that are reflected from their bodies. Wi-Fi based systems still need to address some challenges in order to be able to operate in challenging environments. Some of these challenges include the detection of the weak signal, the detection of abrupt people motion, and the presence of multipath propagation. In this thesis, these three main challenges will be addressed. Firstly, a weak signal detection method that uses the changes in the signals that are reflected from static objects, to improve the detection probability of weak signals that are reflected from the person’s body. Then, a deep learning based Wi-Fi localisation technique is proposed that significantly improves the runtime and the accuracy in comparison with existing techniques. After that, a quantum mechanics inspired tracking method is proposed to address the abrupt motion problem. The proposed method uses some interesting phenomena in the quantum world, where the person is allowed to exist at multiple positions simultaneously. The results show a significant improvement in reducing the tracking error and in reducing the tracking delay

    Reliability and Efficiency of Vehicular Network Applications

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    The DSRC/WAVE initiative is forecast to enable a plethora of applications, classified in two broad types of safety and non-safety applications. In the former type, the reliability performance is of tremendous prominence while, in the latter case, the efficiency of information dissemination is the key driving factor. For safety applications, we adopt a systematic approach to analytically investigate the reliability of the communication system in a symbiotic relationship with the host system comprising a vehicular traffic system and radio propagation environment. To this aim, the¬ interference factor is identified as the central element of the symbiotic relationship. Our approach to the investigation of interference and its impacts on the communication reliability departs from previous studies by the degree of realism incorporated in the host system model. In one dimension, realistic traffic models are developed to describe the vehicular traffic behaviour. In a second dimension, a realistic radio propagation model is employed to capture the unique signal propagation aspects of the host system. We address the case of non-safety applications by proposing a generic framework as a capstone architecture for the development of new applications and the efficiency evaluation of existing ones. This framework, while being independent from networking technology, enables accurate characterization of the various information dissemination tasks that a node performs in cooperation with others. As the central element of the framework, we propose a game theoretic model to describe the interaction of meeting nodes aiming to exchange information of mutual or social interests. An adaptive mechanism is designed to enable a mobile node to measure the social significance of various information topics, which is then used by the node to prioritize the forwarding of information objects

    Proceedings of the Third International Mobile Satellite Conference (IMSC 1993)

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    Satellite-based mobile communications systems provide voice and data communications to users over a vast geographic area. The users may communicate via mobile or hand-held terminals, which may also provide access to terrestrial cellular communications services. While the first and second International Mobile Satellite Conferences (IMSC) mostly concentrated on technical advances, this Third IMSC also focuses on the increasing worldwide commercial activities in Mobile Satellite Services. Because of the large service areas provided by such systems, it is important to consider political and regulatory issues in addition to technical and user requirements issues. Topics covered include: the direct broadcast of audio programming from satellites; spacecraft technology; regulatory and policy considerations; advanced system concepts and analysis; propagation; and user requirements and applications

    Development of an acoustic measurement system of the Modulus of Elasticity in trees, logs and boards

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    The objective of this Bachelor’s Thesis is to develop a portable electronic device capable of quantifying the stiffness of the wood of standing trees, logs and boards using non-destructive testing (NDT) by means of acoustic wave analysis. As an indicator of stiffness, the Modulus of Elasticity (MOE) is used, a standard figure in the industry. This way, wood from forestry can be characterized and classified for different purposes. This Thesis is part of LIFE Wood For Future, a project of the University of Granada (UGR) financed by the European Union’s LIFE programme. LIFE Wood For Future aims to recover the cultivation of poplar (populus sp.) in the Vega de Granada, by proving the quality of its wood through innovative structural bioproducts. Recovering the poplar groves of Granada would have great benefits for the Metropolitan Area: creation of local and sustainable jobs, improvement of biodiversity, and increase in the absorption of carbon dioxide in the long term, helping to reduce the endemic air pollution of Granada. This Final Degree Project has been developed in collaboration with the ADIME research group of the Higher Technical School of Building Engineering (ETSIE) and the aerospace electronics group GranaSat of the UGR. The goal of the developed device, named Tree Inspection Kit (or TIK), is to be an innovative, portable and easy-to-use tool for non-destructive diagnosis and classification of wood by measuring its MOE. TIK is equipped with the necessary electronics to quantify the Time of Flight (ToF) of an acoustic wave that propagates inside a piece of wood. In order to do this, two piezoelectric probes are used, nailed in the wood and separated a given distance longitudinally. The MOE can be derived from the propagation speed of the longitudinal acoustic wave if the density of the is known. For this reason, this device has the possibility of connecting a load cell for weighing logs or boards to estimate their density. It also has an expansion port reserved for future functionality. A methodology based on the Engineering Design Process (EDP) has been followed. The scope of this project embraces all aspects of the development of an electronic product from start to finish: conceptualization, specification of requirements, design, manufacture and verification. A project of this reach requires planning, advanced knowledge of signal analysis, electronics, design and manufacture of Printed Circuit Boards (PCB) and product design, as well as the development of a firmware for the embedded system, based on a RTOS. Prior to the design of the electronics, a Reverse Engineering process of some similar products of the competition is performed; as well as an exhaustive analysis of the signals coming from the piezoelectric sensors that are going to be used, and the frequency response characterization of the piezoelectric probes themselves. This project has as its ultimate goal the demonstration of the multidisciplinary knowledge of engineering, and the capacity of analysis, design and manufacturing by the author; his skill and professionalism in CAD and EDA software required for these tasks, as well as in the documentation of the entire process.El presente Trabajo de Fin de Grado tiene como objetivo el desarrollo de un dispositivo electrónico portátil capaz de cuantificar la rigidez de la madera de árboles en pie, trozas y tablas usando ensayos no destructivos (Non-Destructive Testing, NDT) por medio del análisis de ondas acústicas. Como indicador de la rigidez se usa el Módulo de Elasticidad (MOE), una figura estándar en la industria. Este TFG forma parte de LIFE Wood For Future, un proyecto de la Universidad de Granada (UGR) financiado por el programa LIFE de la Unión Europea. LIFEWood For Future tiene como objetivo recuperar el cultivo del chopo (populus sp.) en la Vega de Granada demostrando la viabilidad de su madera a través de bioproductos estructurales innovadores. Recuperar las choperas de Granada tendría grandes beneficios para la zona del Área Metropolitana: creación de puestos de trabajo locales y sostenibles, mejora de la biodiversidad, e incremento de la tasa de absorción de dióxido de carbono a largo plazo, contribuyendo a reducir la contaminación endémica del aire en Granada. Este Trabajo de Fin de Grado se ha desarrollado con la colaboración del grupo de investigación ADIME de la Escuela Técnica Superior de Ingeniería de Edificación (ETSIE) y el grupo de electrónica aeroespacial GranaSat de la UGR. El objetivo del dispositivo, denominado Tree Inspection Kit (TIK), es ser una herramienta innovadora, portátil y fácil de usar para el diagnóstico y clasificación no destructiva de la madera por medio de su MOE. TIK está dotado de la electrónica necesaria para medir el tiempo de tránsito (ToF) de una onda acústica que se propaga en el interior de una pieza de madera. Para ello, se utilizan dos sondas piezoeléctricas clavadas en la madera y separadas longitudinalmente una distancia conocida. De la velocidad de propagación de la onda longitudinal se puede derivar el MOE, previo conocimiento de la densidad del material. Por ello, este dispositivo cuenta con la posibilidad de conectarle una célula de carga y pesar trozas o tablas para estimar su densidad. También tiene un puerto de expansión reservado para funcionalidad futura. Se ha seguido una metodología basada en el Proceso de Diseño de Ingeniería (Engineering Design Process, EDP), abarcando todos los aspectos del desarrollo de un producto electrónico de principio a fin: conceptualización, especificación de requisitos, diseño, fabricación y verificación. Un proyecto de este alcance requiere de planificación, conocimientos avanzados de análisis de señales, de electrónica, de diseño y fabricación de Placas de Circuito Impreso (PCB) y de diseño de producto, así como el desarrollo de un firmware para el sistema empotrado, basado en un RTOS. Previo al diseño de la electrónica, se realiza un proceso de Ingeniería Inversa (Reverse Engineering) de algunos productos similares de la competencia; al igual que un exhaustivo análisis de las señales provenientes de los sensores piezoeléctricos que van a utilizarse y la caracterización en frecuencia de las propias sondas piezoeléctricas. Este proyecto tiene como fin último la demostración de los conocimientos multidisciplinares propios de la ingeniería y la capacidad de análisis, diseño y fabricación por parte del autor; su habilidad y profesionalidad en el software CAD y EDA requerido para estas tareas, así como en la documentación de todo el proceso.Unión Europe

    Satellite Communications

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    This study is motivated by the need to give the reader a broad view of the developments, key concepts, and technologies related to information society evolution, with a focus on the wireless communications and geoinformation technologies and their role in the environment. Giving perspective, it aims at assisting people active in the industry, the public sector, and Earth science fields as well, by providing a base for their continued work and thinking

    The synergistic effect of operational research and big data analytics in greening container terminal operations: a review and future directions

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    Container Terminals (CTs) are continuously presented with highly interrelated, complex, and uncertain planning tasks. The ever-increasing intensity of operations at CTs in recent years has also resulted in increasing environmental concerns, and they are experiencing an unprecedented pressure to lower their emissions. Operational Research (OR), as a key player in the optimisation of the complex decision problems that arise from the quay and land side operations at CTs, has been therefore presented with new challenges and opportunities to incorporate environmental considerations into decision making and better utilise the ‘big data’ that is continuously generated from the never-stopping operations at CTs. The state-of-the-art literature on OR's incorporation of environmental considerations and its interplay with Big Data Analytics (BDA) is, however, still very much underdeveloped, fragmented, and divergent, and a guiding framework is completely missing. This paper presents a review of the most relevant developments in the field and sheds light on promising research opportunities for the better exploitation of the synergistic effect of the two disciplines in addressing CT operational problems, while incorporating uncertainty and environmental concerns efficiently. The paper finds that while OR has thus far contributed to improving the environmental performance of CTs (rather implicitly), this can be much further stepped up with more explicit incorporation of environmental considerations and better exploitation of BDA predictive modelling capabilities. New interdisciplinary research at the intersection of conventional CT optimisation problems, energy management and sizing, and net-zero technology and energy vectors adoption is also presented as a prominent line of future research

    Intelligent Circuits and Systems

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    ICICS-2020 is the third conference initiated by the School of Electronics and Electrical Engineering at Lovely Professional University that explored recent innovations of researchers working for the development of smart and green technologies in the fields of Energy, Electronics, Communications, Computers, and Control. ICICS provides innovators to identify new opportunities for the social and economic benefits of society.  This conference bridges the gap between academics and R&D institutions, social visionaries, and experts from all strata of society to present their ongoing research activities and foster research relations between them. It provides opportunities for the exchange of new ideas, applications, and experiences in the field of smart technologies and finding global partners for future collaboration. The ICICS-2020 was conducted in two broad categories, Intelligent Circuits & Intelligent Systems and Emerging Technologies in Electrical Engineering

    Channel parameter tuning in a hybrid Wi-Fi-Dynamic Spectrum Access Wireless Mesh Network

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    This work addresses Channel Assignment in a multi-radio multi-channel (MRMC) Wireless Mesh Network (WMN) using both Wi-Fi and Dynamic Spectrum Access (DSA) spectrum bands and standards. This scenario poses new challenges because nodes are spread out geographically so may have differing allowed channels and experience different levels of external interference in different channels. A solution must meet two conflicting requirements simultaneously: 1) avoid or minimise interference within the network and from external interference sources, and 2) maintain connectivity within the network. These two requirements must be met while staying within the link constraints and the radio interface constraints, such as only assigning as many channels to a node as it has radios. This work's original contribution to the field is a unified framework for channel optimisation and assignment in a WMN that uses both DSA and traditional Wi-Fi channels for interconnectivity. This contribution is realised by providing and analysing the performance of near-optimal Channel Assignment (CA) solutions using metaheuristic algorithms for the MRMC WMNs using DSA bands. We have created a simulation framework for evaluating the algorithms. The performance of Simulated Annealing, Genetic Algorithm, Differential Evolution, and Particle Swarm Optimisation algorithms have been analysed and compared for the CA optimisation problem. We introduce a novel algorithm, used alongside the metaheuristic optimisation algorithms, to generate feasible candidate CA solutions. Unlike previous studies, this sensing and CA work takes into account the requirement to use a Geolocation Spectrum Database (GLSD) to get the allowed channels, in addition to using spectrum sensing to identify and estimate the cumulative severity of both internal and external interference sources. External interference may be caused by other secondary users (SUs) in the vicinity or by primary transmitters of the DSA band whose emissions leak into adjacent channels, next-toadjacent, or even into further channels. We use signal-to-interference-plus-noise ratio (SINR) as the optimisation objective. This incorporates any possible source or type of interference and makes our method agnostic to the protocol or technology of the interfering devices while ensuring that the received signal level is high enough for connectivity to be maintained on as many links as possible. To support our assertion that SINR is a reasonable criterion on which to base the optimisation, we have carried out extensive outdoor measurements in both line-of-sight and wooded conditions in the television white space (TVWS) DSA band and the 5 GHz Wi-Fi band. These measurements show that SINR is useful as a performance measure, especially when the interference experienced on a link is high. Our statistical analysis shows that SINR effectively differentiates the performance of different channels and that SINR is well correlated with throughput and is thus a good predictor of end-user experience, despite varying conditions. We also identify and analyse the idle times created by Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) contention-based Medium Access Control (MAC) operations and propose the use of these idle times for spectrum sensing to measure the SINR on possible channels. This means we can perform spectrum sensing with zero spectrum sensing delay experienced by the end user. Unlike previous work, this spectrum sensing is transparent and can be performed without causing any disruption to the normal data transmission of the network. We conduct Markov chain analysis to find the expected length of time of a sensing window. We also derive an efficient minimum variance unbiased estimator of the interference plus noise and show how the SINR can be found using this estimate. Our estimation is more granular, accurate, and appropriate to the problem of Secondary User (SU)-SU coexistence than the binary hypothesis testing methods that are most common in the literature. Furthermore, we construct confidence intervals based on the probability density function derived for the observations. This leads to finding and showing the relationships between the number of sampling windows and sampling time, the interference power, and the achievable confidence interval width. While our results coincide with (and thus are confirmed by) some key previous recommendations, ours are more precise, granular, and accurate and allow for application to a wider range of operating conditions. Finally, we present alterations to the IEEE 802.11k protocol to enable the reporting of spectrum sensing results to the fusion or gateway node and algorithms for distributing the Channel Assignment once computed. We analyse the convergence rate of the proposed procedures and find that high network availability can be maintained despite the temporary loss of connectivity caused by the channel switching procedure. This dissertation consolidates the different activities required to improve the channel parameter settings of a multi-radio multi-channel DSA-WMN. The work facilitates the extension of Internet connectivity to the unconnected or unreliably connected in rural or peri-urban areas in a more cost-effective way, enabling more meaningful and affordable access technologies. It also empowers smaller players to construct better community networks for sharing local content. This technology can have knock-on effects of improved socio-economic conditions for the communities that use it
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