20 research outputs found

    Validity and User Experience in an Augmented Reality Virtual Tooth Identification Test

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    Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/153623/1/jddjde019139.pd

    ANALYTICAL MODELING AND SIMULATION OF RELIABILITY OF A CLOSED HOMOGENEOUS SYSTEM WITH AN ARBITRARY NUMBER OF DATA SOURCES AND LIMITED RESOURCES FOR THEIR PROCESSING

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    Continuous development of computer networks and data transmission systems underlines the growing need for adequate mathematical models and methods for analyzing the performance and reliability metrics of these systems, taking into account the performance of their redundant components. We consider a mathematical model of a repairable data transmission system as a model of a closed homogeneous cold standby system with a single repair facility and with exponentially distributed lifetimes and generally distributed repair times of the system's elements. We study the system-level reliability, defined as the stationary probability of failure-free operation of the considered system. The proposed analytical methodology made it possible to evaluate the reliability of the entire system in case of failures of its elements. Explicit analytical expressions were obtained for the stationary probability of the system's failure-free operation and stationary system state probabilities, which allow analyzing other operational characteristics of the system with respect to the performance of its redundant elements. Explicit analytical expressions for the stationary state probabilities of the considered system cannot always be obtained; therefore, to obtain results in the case of general distribution of elements' repair time, a discrete-event simulation model was constructed to approximate the analytical model of the system. The simulation algorithm was programmatically implemented in R. The comparison of numerical and graphical results obtained using both analytical and simulation approaches showed that they were in close agreement, so the proposed simulation model can be used in cases where the analytical solution cannot be obtained explicitly or as part of a more complex simulation model. We’ve also studied the problem of analyzing the sensitivity of the reliability characteristics of the system at hand to the shape of input distributions. The obtained formulas showed the presence of an explicit dependence of these characteristics on the types of distribution functions of the repair time of the system's elements. However, numerical studies and graphical analysis have shown that this dependence becomes vanishingly small with the “fast” restoration of the system's element

    Reopening for Business Post-COVID-19: Augmented Reality as a Strategy for Attracting Visitors to a Tourist Destination

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    Critical thoughts about tourist destinations overcoming and mitigating impacts from COVID-19 lie in the opportunities created by the pandemic. In this paper, an innovative way to attract tourists to Madeira Island and specifically for the Caminho Real (CR) is proposed, assisted by augmented reality. There are important con siderations for developing software suitable for mobile devices such as smartphones and tablets; values and benefits for sustainable tourism development and for being an educational experience respecting social dis tancing; and services included in the augmented reality application. Therefore, some propositions are presented to evaluate the possibility of augmented reality as a secure opportunity to show historical, cultural, and eth nographic aspects when visiting a tourist destination, while respecting social-distancing constraints.info:eu-repo/semantics/publishedVersio

    5G Smart and innovative Healthcare services: opportunities, challenges and prospective solutions

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    Due to its abilities to boost productivity, reduce costs and enhance user experiences, smart healthcare is widely recognised as a potential solution to reduce pressures on existing health systems. Since the new era of 5G will unite enhanced connectivity, improved cloud-based storage and interconnection of an array of devices and services, a massive boost in the digital transformation of healthcare is expected. In this transformation process, healthcare services such as medical diagnosis, treatment and remote surgery will be facilitated by a range of technologies such as Internet of Things, Robotics and Artificial Intelligence, among others, that will advance further under 5G. Moreover, real-time health services will become a reality and will offer people with quality care and improved experiences. On the other hand, different challenges can hinder the proliferation of 5G smart and innovative healthcare solutions, including security and heterogeneous devices. This chapter presents how 5G will boost digital transformation of healthcare through delivery and consumption of smart and innovative healthcare services, while probing into key hurdles in the process as well as prospective solutions

    Study of Mutual Coupling in Finite Antenna Arrays for Massive MIMO Applications

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    This thesis focuses on the study of mutual coupling (MC) in finite antenna arrays for base station antennas (BSAs) for Massive multiple-input multiple-output (MIMO) applications, with an emphasis on the development of a computationally-efficient modeling technique for the analysis of MC which can be readily applied in the design or synthesis schemes for BSAs. Traditionally, the effects of MC have been ignored or underestimated in the analyses performed within the information-theoretic-based communities by assuming idealized antenna elements with no MC between them or by considering the fictitious isotropic radiator models. In contrast, this thesis demonstrates the essentialness of proper modeling and inclusion of the physical antenna effects in the models used to predict the performance of a Massive MIMO system, as evidenced through the performed sum-rate analysis of a downlink line-of-sight (LoS) MIMO system in the presence of MC.The developed model for the analysis of MC is inspired by the concept of multiple scattering by which the overall effect of the antenna array MC can be determined by cascading the scattering responses of all array elements. Such an approach requires the full-wave characterization of only a single element in isolation, while the mutual interactions between different elements are modeled by approximating the incident field as a single plane wave with mutually-orthogonal polarization taken from the spherical wave expansion (SWE) of the field scattered from any other array element. This process is described mathematically through the iterative scheme based on the classical Jacobi and Gauss-Seidel iterative methods.Additionally, a sum-rate model of a downlink LoS multi-user MIMO system including the MC, has been developed. Herein, the effects of MC are accounted through the S-matrix of the BSA and the embedded element patterns (EEPs) of all BSA elements, which are used to approximate the channel matrix in a LoS environment. The S-matrix and the EEPs obtained by using the Jacobi-based MC model have been incorporated into the MIMO system model, showing good agreement in terms of the achievable sum rate compared to the reference result which uses the MoM-based simulation data. The accuracy and run-time benefits of the Jacobi-based model make it a possibly promising candidate for use in BSA design and synthesis applications, particularly when large array configurations need to be (repeatedly) analyzed

    5G Smart and innovative Healthcare services: opportunities, challenges and prospective solutions

    Get PDF
    Due to its abilities to boost productivity, reduce costs and enhance user experiences, smart healthcare is widely recognised as a potential solution to reduce pressures on existing health systems. Since the new era of 5G will unite enhanced connectivity, improved cloud-based storage and interconnection of an array of devices and services, a massive boost in the digital transformation of healthcare is expected. In this transformation process, healthcare services such as medical diagnosis, treatment and remote surgery will be facilitated by a range of technologies such as Internet of Things, Robotics and Artificial Intelligence, among others, that will advance further under 5G. Moreover, real-time health services will become a reality and will offer people with quality care and improved experiences. On the other hand, different challenges can hinder the proliferation of 5G smart and innovative healthcare solutions, including security and heterogeneous devices. This chapter presents how 5G will boost digital transformation of healthcare through delivery and consumption of smart and innovative healthcare services, while probing into key hurdles in the process as well as prospective solutions

    Challenges in passenger use of mixed reality headsets in cars and other transportation

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    This paper examines key challenges in supporting passenger use of augmented and virtual reality headsets in transit. These headsets will allow passengers to break free from the restraints of physical displays placed in constrained environments such as cars, trains and planes. Moreover, they have the potential to allow passengers to make better use of their time by making travel more productive and enjoyable, supporting both privacy and immersion. However, there are significant barriers to headset usage by passengers in transit contexts. These barriers range from impediments that would entirely prevent safe usage and function (e.g. motion sickness) to those that might impair their adoption (e.g. social acceptability). We identify the key challenges that need to be overcome and discuss the necessary resolutions and research required to facilitate adoption and realize the potential advantages of using mixed reality headsets in transit
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