63 research outputs found

    Multi-Hop Relay Networks

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    QoS management in UMTS terrestrial radio access FDD networks

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    This work investigates the role and importance of some of the key aspects of QoS planning, provisioning, monitoring and optimisation (QoS Management) for UMTS Terrestrial Radio Access (UTRA) FDD networks within the framework of the 3rd Generation Partnership Project (3GPP). Firstly, the differences between Quality of end user Experience (QoE) and Quality of Service (QoS) are explained. This is followed by a review of 3GPP requirements for QoS concept and architecture. Then all models and the main assumptions in this dissertation are presented. Based on these, original QoS mechanisms in the radio access network domain, means and methods for QoS provisioning, planning, monitoring and "optimisation" are discussed. Simulation results showed substantial spectral efficiency gains provided by service (or user) differentiation in UTRAN by means of priorities and differentiated parameter settings. When appropriately configured, the proposed QoS mechanisms can greatly reduce the need for bandwidth. Performance results proved also the proposed virtual time simulator to be an appropriate tool for service driven WCDMA radio interface dimensioning and detailed radio network planning. It is also shown that measuring QoS performance by a proper classification of counters (and or gauges), based on a particular subset of radio access bearer attributes, is a promising technique for assessing performances of service applications through WCDMA networks. With this new method there is no need to trace upper layer protocols at different interfaces or dumping data in mobile terminals. The proposed metrics allow operators to measure the bandwidth required for robust statistical reliability, to assess and exploit statistical sharing of resources, to configure QoS functions effectively, and to monitor QoE. The application of the proposed technique is not limited to the WCDMA Radio Network Subsystem (RNS), yet it can be deployed in any radio access and packet core network supporting mapping of performance indicators onto a particular subset of QoS attributes. Finally, in order to maximise the performance of the available services in UTRAN, at a given QoE, simulation results showed clear needs for the network administrator to adapt the parameter settings to diverse input application traffic conditions and the proposed genetic approach to be an appropriate solution space search algorithm for this purpose.reviewe

    Temperature sensor based on fiber optic pyrometer in material removal processes

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    This proceeding at: 22nd International Conference on Optical Fibre Sensors (OFS-2012), took place in 2012 October-15-19, in Pekin (Chine).In this work, different non-contact fiber-optic pyrometers have been developed for measuring localized temperatures on material removal area during mechanizing processes. Designs are developed for adaptation to the harsh measuring conditions on specific cutting tool machinery and using commercial optoelectronics and fiber-optic components for resolution enhancement. A 0.1 dB/ºC sensitivity at 300 ºC is obtained, and calibration curves at 1100 nm, 1300 nm, 1550 nm and 1610 nm are reported. Different reception circuits are used for testing resolution limits, higher bandwidths imply greater noise and worst results as expected.This work has been sponsored by the Spanish Ministry of Science and Innovation within project TEC2009-14718-C03-03 and by FACTOTEM-II-C: S2009/ESP-1781 of Comunidad Autónoma de Madrid.Publicad

    eBPF: A New Approach to Cloud-Native Observability, Networking and Security for Current (5G) and Future Mobile Networks (6G and Beyond)

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    Modern mobile communication networks and new service applications are deployed on cloud-native platforms. Kubernetes (K8s) is the de facto distributed operating system for container orchestration, and the extended version of the Berkeley Packet Filter (eBPF)- in the Linux (and MS Windows) kernel- is fundamentally changing the approach to cloud-native networking, security, and observability. In this paper, we introduce what eBPF is, its potential for Telco cloud, and review some of the most promising pricing and billing models applied to this revolutionary operating system (OS) technology. These models include schemes based on a data source usage model or the number of eBPF agents deployed on the network, linked to specific eBPF modules. These modules encompass network observability, runtime security, and power dissipation monitoring. Next, we present our eBPF platform, named Sauron in this work, and demonstrate how eBPF allows us to write custom code and dynamically load eBPF programs into the kernel. These programs enable us to estimate the energy consumption of cloud-native functions, derive performance counters and gauges for transport networks, 5G applications, and non-access stratum protocols. Additionally, we can detect and respond to unauthorized access to cloud-native resources in real-time using eBPF. Our experimental results demonstrate the technical feasibility of eBPF in achieving highly performant monitoring, observability, and security tooling for current mobile networks (5G, 5G Advanced) as well as future networks (6G and beyond)

    Efficacy of β-lactam/β-lactamase inhibitors to treat extended-spectrum beta-lactamase-producing Enterobacterales bacteremia secondary to urinary tract infection in kidney transplant recipients (INCREMENT-SOT Project)

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    REIPI/INCREMENT-SOT Group.[Background] Whether active therapy with β-lactam/β-lactamase inhibitors (BLBLI) is as affective as carbapenems for extended-spectrum β-lactamase-producing Enterobacterales (ESBL-E) bloodstream infection (BSI) secondary to urinary tract infection (UTI) in kidney transplant recipients (KTRs) remains unclear.[Methods] We retrospectively evaluated 306 KTR admitted to 30 centers from January 2014 to October 2016. Therapeutic failure (lack of cure or clinical improvement and/or death from any cause) at days 7 and 30 from ESBL-E BSI onset was the primary and secondary study outcomes, respectively.[Results] Therapeutic failure at days 7 and 30 occurred in 8.2% (25/306) and 13.4% (41/306) of patients. Hospital-acquired BSI (adjusted OR [aOR]: 4.10; 95% confidence interval [CI]: 1.50-11.20) and Pitt score (aOR: 1.47; 95% CI: 1.21-1.77) were independently associated with therapeutic failure at day 7. Age-adjusted Charlson Index (aOR: 1.25; 95% CI: 1.05-1.48), Pitt score (aOR: 1.72; 95% CI: 1.35-2.17), and lymphocyte count ≤500 cells/μL at presentation (aOR: 3.16; 95% CI: 1.42-7.06) predicted therapeutic failure at day 30. Carbapenem monotherapy (68.6%, primarily meropenem) was the most frequent active therapy, followed by BLBLI monotherapy (10.8%, mostly piperacillin-tazobactam). Propensity score (PS)-adjusted models revealed no significant impact of the choice of active therapy (carbapenem-containing vs any other regimen, BLBLI- vs carbapenem-based monotherapy) within the first 72 hours on any of the study outcomes.[Conclusions] Our data suggest that active therapy based on BLBLI may be as effective as carbapenem-containing regimens for ESBL-E BSI secondary to UTI in the specific population of KTR. Potential residual confounding and unpowered sample size cannot be excluded (ClinicalTrials.gov identifier: NCT02852902).This work was supported by: (1) Plan Nacional de I+D+i 2013-2016 and Instituto de Salud Carlos III (ISCIII), Subdirección General de Redes y Centros de Investigación Cooperativa, Ministerio de Ciencia, Innovación y Universidades, Spanish Network for Research in Infectious Diseases [RD16/0016/0001, RD16/0016/0002, REIPI RD16/0016/0008; RD16/0016/00010], co-financed by European Development Regional Fund “A way to achieve Europe”, Operative Program Intelligent Growth 2014-2020; (2) European Society of Clinical Microbiology and Infectious diseases Study Group for Infections in Compromised Hosts (ESGICH, grant to J.M.A.); (3) Sociedad Andaluza de Trasplante de Órgano Sólido (SATOT, grant to L.M.M.); (4) Research project PI16/01631 integrated into the Plan Estatal de I+D+I 2013-2016 and co-financed by the ISCIII-Subdirección General de Evaluación y Fomento de la Investigación and the Fondo Europeo de Desarrollo Regional (FEDER); (5) M.F.R. holds a research contract “Miguel Servet” (CP 18/00073) from ISCIII, Ministerio de Ciencia, Innovación y Universidades. The work was also supported by the following European Society of Clinical Microbiology and Infectious diseases (ESCMID) study groups: Infections in Compromised Hosts (ESGICH), Bloodstream Infections and Sepsis (ESGBIS) and Antimicrobial Resistance Surveillance (ESGARS).Peer reviewe

    Comparing Notes: Recording and Criticism

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    This chapter charts the ways in which recording has changed the nature of music criticism. It both provides an overview of the history of recording and music criticism, from the advent of Edison’s Phonograph to the present day, and examines the issues arising from this new technology and the consequent transformation of critical thought and practice

    Wider Still and Wider: British Music Criticism since the Second World War

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    This chapter provides the first historical examination of music criticism in Britain since the Second World War. In the process, it also challenges the simplistic prevailing view of this being a period of decline from a golden age in music criticism

    Stop the Press? The Changing Media of Music Criticism

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    Temperature sensor based on fiber optic pyrometer in material removal processes

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    This proceeding at: 22nd International Conference on Optical Fibre Sensors (OFS-2012), took place in 2012 October-15-19, in Pekin (Chine).In this work, different non-contact fiber-optic pyrometers have been developed for measuring localized temperatures on material removal area during mechanizing processes. Designs are developed for adaptation to the harsh measuring conditions on specific cutting tool machinery and using commercial optoelectronics and fiber-optic components for resolution enhancement. A 0.1 dB/ºC sensitivity at 300 ºC is obtained, and calibration curves at 1100 nm, 1300 nm, 1550 nm and 1610 nm are reported. Different reception circuits are used for testing resolution limits, higher bandwidths imply greater noise and worst results as expected.This work has been sponsored by the Spanish Ministry of Science and Innovation within project TEC2009-14718-C03-03 and by FACTOTEM-II-C: S2009/ESP-1781 of Comunidad Autónoma de Madrid.Publicad
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