Metrics for Broadband Networks in the Context of the Digital Economies

In a transition to automated digital management of broadband networks, communication service providers must look for new metrics to monitor these networks. Complete metrics frameworks are already emerging whereas majority of the new metrics are being proposed in technical papers. Considering common metrics for broadband networks and related technologies, this chapter offers insights into what metrics are available, and also suggests active areas of research. The broadband networks being a key component of the digital ecosystems are also an enabler to many other digital technologies and services. Reviewing first the metrics for computing systems, websites and digital platforms, the chapter focus then shifts to the most important technical and business metrics which are used for broadband networks. The demand-side and supply-side metrics including the key metrics of broadband speed and broadband availability are touched on. After outlining the broadband metrics which have been standardized and the metrics for measuring Internet traffic, the most commonly used metrics for broadband networks are surveyed in five categories: energy and power metrics, quality of service, quality of experience, security metrics, and robustness and resilience metrics. The chapter concludes with a discussion on machine learning, big data and the associated metrics

Enabling connectivity for tactical networks in mountainous areas by aerial relays

The dimension of the Meiac as a diffuser of Latin American art has been key in Spain in the late twentieth century. The genesis of the museum, its cultural policy of debate and diffusion, and the creation of a Latin American collection, which until then did not exist in Spain, forced Spanish art criticism to look at and reconsider work from Latin America. At present the Meiac has developed the new technological platforms, as a new perspective of identity and common imaginaries between Spain and Latin America.La dimensión del Meiac como difusor del arte latinoamericano ha sido clave en España a finales del siglo XX. La génesis del museo, su política cultural de debate y difusión y la creación de una colección latinoamericana, hasta entonces inexistente en España, obligó a la crítica artística española a mirar y a reconsiderar la obra procedente de Latinoamérica. En la actualidad el Meiac ha desarrollado las nuevas plataformas tecnológicas, como una nueva perspectiva de identidad e imaginarios comunes entre España y América Latina

Design and performance evaluation of bitwise retransmission schemes in wireless sensor networks

The previously proposed bitwise retransmission schemes which retransmit only selected bits to accumulate their reliability are designed and evaluated. Unlike conventional automatic repeat request (ARQ) schemes, the bitwise retransmission schemes do not require a checksum for error detection. The bitwise retransmission decisions and combining can be performed either after demodulation of the received symbols or after channel decoding. The design and analysis assume error-free feedback, however, the impact of feedback errors is also considered. The bit-error rate (BER) expressions are derived and verified by computer simulations in order to optimize the parameters of the retransmission schemes. The BER performance of coded and uncoded bitwise retransmissions is compared with a hybrid ARQ (HARQ) scheme over additive white Gaussian noise (AWGN), slow fading, and fast fading channels. It is shown that bitwise retransmissions outperform block repetition coding (BRC) over AWGN channels. In addition, the selection diversity created by the bitwise retransmissions can outperform the HARQ at large signal-to-noise ratio (SNR) over fast fading channels. Finally, the practical design of a bitwise retransmission protocol for data fusion in wireless sensor networks is presented assuming Zigbee, WiFi and Bluetooth system parameters

Enabling connectivity for tactical networks in mountainous areas by aerial relays

A general modeling framework for realistic performance evaluations of tactical mobile ad-hoc networks deployed in mountainous areas is presented. The framework is easily extensible, and can be eventually automated. It can be also used to generate data for other network simulators. The framework utilizes the freely downloadable high resolution 3D terrain data to define time dependent trajectories of network nodes. The node speeds and directions are linked to the terrain profile which extends the previously proposed mobility models. The path-loss analysis along the node trajectories revealed the need for aerial relays to enable full network connectivity at all times. The network consisting of 5 cluster heads and a single stationary relay is considered as a case study. The relay location and its antenna height are optimized to achieve the line-of-sight connectivity over the whole mission duration. The antenna radiation pattern at the relay is incorporated in the analysis. The resulting star network topology is used by the cluster heads to broadcast their packets to all other cluster heads. Several relaying schemes including the amplify-and-forward and the decode-and-forward relaying are studied together with the go-back-N retransmissions to achieve the reliable data transfer

E-Cigarette Use among Male Smokers in Al-Ahsa, Kingdom of Saudi Arabia: A Cross-Sectional Study

E-cigarette use is increasing globally. Recent evidence suggests that e-cigarettes contain harmful substances that could cause adverse health outcomes. This study investigated the prevalence and associated factors of e-cigarette use among male current smokers in Saudi Arabia. We conducted a cross-sectional survey of adult male current smokers in the Al-Ahsa province of Saudi Arabia. Data were collected using a structured questionnaire. We performed logistic regression analyses to investigate the factors associated with e-cigarette use among adult male current smokers. 325 current smokers participated in the study. A third of them (33.5%) were e-cigarette users. Almost all the study participants (97.0%) had heard about e-cigarettes. Participants who were occasional smokers (Odds Ratio (OR): 2.28; 95% Confidence Interval (CI): 1.17–4.41) and had good knowledge perception of e-cigarettes (OR 3.49; 95% CI: 2.07–5.90) had higher odds of using e-cigarettes when compared to regular smokers of conventional cigarettes and current smokers with poor knowledge perception of e-cigarettes, respectively. In contrast, private employees (OR: 0.25, 95% CI: 0.07–0.85), and business owners (OR: 0.09, 95% CI: 0.01–0.63) had lower odds of using e-cigarettes compared to unemployed individuals. Compared with non-e-cigarette users, the rate of conventional cigarette smoking per day was significantly lower among e-cigarette users. Use of e-cigarette (OR: 3.57, 95% CI: 2.14–5.98), believing that e-cigarette quitting is hard (OR: 2.02, 95% CI: 1.17–3.49) and trying to quit e-cigarettes (OR: 2.17, 95% CI: 1.1–4.25) were found to be significant predictors of good knowledge perception of e-cigarettes among the current smokers. The use and knowledge perception of e-cigarettes were higher among occasional conventional male cigarette smokers than regular male smokers in Al-Ahsa province. The use of e-cigarettes as smoking cessation aids should be examined further in the Saudi Arabian setting