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Current networking protocols deem inefficient in accommodating the two key challenges of Unmanned Aerial Vehicle (UAV) networks, namely the network connectivity loss and energy limitations. One approach to solve these issues is using learning-based routing protocols to make close-to-optimal local decisions by the network nodes, and Q-routing is a bold example of such protocols. However, the performance of the current implementations of Q-routing algorithms is not yet satisfactory, mainly due to the lack of adaptability to continued topology changes. In this paper, we propose a full-echo Q-routing algorithm with a self-adaptive learning rate that utilizes Simulated Annealing (SA) optimization to control the exploration rate of the algorithm through the temperature decline rate, which in turn is regulated by the experienced variation rate of the Q-values. Our results show that our method adapts to the network dynamicity without the need for manual re-initialization at transition points (abrupt network topology changes). Our method exhibits a reduction in the energy consumption ranging from 7% up to 82%, as well as a 2.6 fold gain in successful packet delivery rate}, compared to the state of the art Q-routing protocols, Comment: 13 pages, 7 figures, 5 tables

Blockchain is an emerging technology that uses distributed ledgers for transparent, reliable, and traceable information exchange among network nodes. Blockchain and its 3rd generation Tangle-based implementations quickly extend their territory beyond crypto-currency to a broad range of applications using fee-less transactions over the Internet of things (IoT). However, this technology suffers from sluggishness in consensus-based validation of information that restricts its applicability to time-sensitive applications such as smart health. In this letter, we propose an optimized policy for sampling rate by IoT sensors that utilize blockchain and Tangle technologies for their transmission with the goal of minimizing the age of information (AoI) experienced by the end-users, considering both processing and networking resource constraints. Simulation results confirm the efficacy of the proposed algorithm compared to the current fixed-rate update policy. Further, a closed-form solution is obtained for the optimal sampling rate in a network of homogeneous IoT nodes as a benchmark system.

Unmanned Aerial Vehicles (UAVs), as a recently emerging technology, enabled a new breed of unprecedented applications in different domains. This technology's ongoing trend is departing from large remotely-controlled drones to networks of small autonomous drones to collectively complete intricate tasks time and cost-effectively. An important challenge is developing efficient sensing, communication, and control algorithms that can accommodate the requirements of highly dynamic UAV networks with heterogeneous mobility levels. Recently, the use of Artificial Intelligence (AI) in learning-based networking has gained momentum to harness the learning power of cognizant nodes to make more intelligent networking decisions by integrating computational intelligence into UAV networks. An important example of this trend is developing learning-powered routing protocols, where machine learning methods are used to model and predict topology evolution, channel status, traffic mobility, and environmental factors for enhanced routing. This paper reviews AI-enabled routing protocols designed primarily for aerial networks, including topology-predictive and self-adaptive learning-based routing algorithms, with an emphasis on accommodating highly-dynamic network topology. To this end, we justify the importance and adaptation of AI into UAV network communications. We also address, with an AI emphasis, the closely related topics of mobility and networking models for UAV networks, simulation tools and public datasets, and relations to UAV swarming, which serve to choose the right algorithm for each scenario. We conclude by presenting future trends, and the remaining challenges in AI-based UAV networking, for different aspects of routing, connectivity, topology control, security and privacy, energy efficiency, and spectrum sharing., Comment: 30 pages, 9 figures, 8 tables

Background and objectives: Immunosuppression is a known risk factor for cervical cancer. Women with rheumatic conditions are immunosuppressed due to the disease and the treatments. One of the main risk factors for this neoplasm is the lack of adherence to early detection programmes for human papillomavirus. The objectives of this study were to evaluate the adherence to the screening programme of patients in the Rheumatology Clinic, as well as to evaluate the prevalence of cervical lesions and their association with the different disease characteristics and the treatments received. Methods: A descriptive retrospective study. The electronic medical history of patients actively being followed up in a tertiary hospital with rheumatoid arthritis (RA), psoriatic arthritis (PSA) and systemic lupus erythematosus (SLE) were reviewed. Results: Finally, 307 patients were included. No data were found for screening programme attendance in up to 42.4% of the patients (39.6% in RA, 43.8% in PSA and 46% in SLE). Among the patients who attended the screening programme at least once (57.6%), the prevalence of cervical dysplasia was 5.1%. No cases of neoplasia were found. In the simple logistic regression analysis, there was no association between attending the screening programme and any variable. The study also showed no association between the variables collected and the presence of infection and dysplasia. Conclusion: These results are influenced by the absence of screening data in a significant percentage of patients and by the low prevalence of dysplasia found in this series of patients with rheumatic diseases. (C) 2020 Elsevier Espana, S.L.U. and Sociedad Espanola de Reumatologia y Colegio Mexicano de Reumatologia. All rights reserved.

Managing energy consumption for computation and communication is a key requirement for flying ad hoc networks (FANET) to prolong the network lifetime. In many applications, the main role of drones is to collect imagery information and relay them to a ground station for further processing and decision making. In this paper, we present a predictive compression policy to maximize the end-to-end image quality penalized by the communication and computation costs. The idea is to predict the number of remaining links to the destination for a given routing algorithm and use it to re-compress image frames at intermediate nodes such that the overall energy consumption is minimized. Numerical results confirm that the performance of this method is within 4% of the global optima and higher than the current fixed-rate policies with a significant margin.

Emerging Internet of Things (IoT) provides connectivity to a wide range of mobile nodes including indoor wireless users, pedestrian, ground robotics, vehicles, and flying objects. Such decentralized network require rethinking user-centric communication protocols which accommodate extremely dynamic environments of autonomous nodes. The authors recently proposed a predictive routing algorithm, which enables a delay-optimal communication through incorporating network topology prediction into the Dijkstra's shortest path algorithm. In this work, we extend the proposed solution to jointly optimize the end-to-end latency and total transmission power. Further, we develop a ground robotics platform in order to study the utility of the proposed algorithm in real-world applications. The simulation results which verified by the test platform, confirm the superiority of the proposed algorithm compared to the conventional shortest path algorithms by improving the delay and power consumption by a factor of 10% to 15%.

The emerging Flying Ad-Hoc Networks (FANETs) provide efficient infrastructure solutions for a wide range of military and commercial applications. These networks are typically composed of high-speed Unmanned Aerial Vehicles (UAVs) and form dynamic network topologies. As such, conventional routing algorithms do not efficiently accommodate these continued topology changes and exhibit poor delay performances. In this paper, we introduce an optimal routing algorithm for UAV networks with queued communication systems based on Dijkstra's shortest path algorithm as a primary step towards developing a fully predictive communication platform. The core idea is to incorporate the anticipated locations of intermediate nodes during a transmission session into the path selection criterion. We further evaluate the impact of measurement uncertainties on choosing the optimal path and on the resulting end-to-end delay. The simulation results confirm the superior delay performance of the proposed algorithm compared to the conventional routing algorithms. The enhancement is more significant, when the network size is larger, the relative node velocities are higher, and the average waiting times in transmit buffers are longer.

This document presents several original OGSEs, Optical Ground Support Equipment, specifically designed and realized for the optical testing and calibration of earth observation satellites operating in a large spectral band from 0.4μm to 14.7μm. This work has been mainly supported by recent development dedicated to MTG, Meteosat Third Generation, the ESA next generation of meteorological satellites. The improved measurement capabilities of this new satellite generation has generated new challenging requirements for the associated optical test equipments. These improvements, based on design and component innovation will be illustrated for the MOTA, the GICS and the DEA OGSEs. MOTA and GICS are dedicated to the AIT, Assembly Integration and Test, of FCI, the Flexible Combined Imager of the imaging satellite MTG-I. DEA OGSE is dedicated to the AIT of the DEA, Detection Electronics Assembly, which is part of IRS instrument, an IR sounder part of MTG-S satellite. From an architectural point of view, the presented original designs enable to run many optical tests with a single system thanks to a limited configuration effort. Main measurement capabilities are optical quality testing (MTF based mainly on KEF measurement), Line of Sight (LoS) stability measurement, straylight analyses, VNIR-MWIR-LWIR focal plane array co-registration, and broadband large dynamic spectro-radiometric calibration. Depending on the AIT phase of the satellite, these source assemblies are operated at atmospheric pressure or under secondary vacuum. In operation, they are associated with an opto-mechanical projection system that enables to conjugate the image of the source assembly with the focal plane of the satellite instruments. These conjugation systems are usually based on high resolution, broadband collimator, and are optionally mounted on hexapod to address the entire field of instruments.

Through ALA projects in Latin America, American librarianship progressed, step by step, from conceptualization to implementation as the model to be followed by the Latin American countries in modernizing not only their library practices but their societies in general. The development of library practices was fundamental to the pursuit of a "modern" society. In fighting fascist propaganda, the United States has portrayed itself at least since World War II as a "modern" model whose prosperity and economic growth were important achievements but achievable only in a democratic society.

Graphene-enabled Wireless Communications (GWC) advocate for the use of graphene-based plasmonic antennas, or graphennas, which take advantage of the plasmonic properties of graphene to radiate electromagnetic waves in the terahertz band (0.1-10 THz). GWC may represent a breakthrough in the research areas of wireless on-chip communications, i.e., among the different processors or cores of a chip multiprocessor, and of these cores with the memory system. The main advantages of the resulting Graphene-enabled Wireless Networks on-Chip (GWNoC) are twofold. On the one hand, the potential of GWCto radiate in the terahertz band provides a huge transmission bandwidth, allowing not only the transmission of information at extremely high speeds but also the design of ultra-low-power and low-complexity schemes. On the other hand, the size of graphennas can be greatly reduced with respect to metallic antennas with the same resonant frequency, allowing the integration of graphennas within individual processing cores and the implementation of core-level wireless communication. In addition to these physical layer advantages, GWNoC represent a clear opportunity from the multicore architecture perspective. Due to their native implementation of broadcast and multicast communications, GWNoC will enable not just the alleviation of the latency or power bottlenecks of traditional on-chip networks, but also the devising of novel multicore architectures.

The effect of nitrogen fertilization and water stress on the spectral signature of winter wheat Triticum aestivum cv. Astral were measured with a field radiometer over two years. Spectral reflectance of the canopy has been related to the most indicative physiological parameters (nitrogen and photosynthctic pigment content, biomass, leaf area and LAI), but only a few of these parameters can be estimated independently of plant treatment. The normalized difference vegetation index seems the most powerful spectral combination with which to estimate the total area of plant leaves and LAI. The nitrogen content of plants can also be related to a linear combination of green and red canopy reflectances independently of plant treatment. Relations between canopy reflectance and other physiological parameters are not independent of plant treatment.

The virtual analog and digital communications laboratory LaViCAD has been designed at the UPC and it results a useful tool to verify different communication systems performance and also signal processing techniques, subjects given in courses typically included in the curriculum of any electrical engineering degree. LaViCAD tool has become a flexible, sustainable and on-line freely offered educational platform and it can be updated whenever new content is required. At pedagogical level, the use of a virtual laboratory facilitates the learning of certain matters, acting as a connection between the theoretical contents of a communications system course and their practical understanding and experimentation. Furthermore, LAVICAD provides resources for professors to organize different teaching activities in their courses. These activities can be used in different environments as for instance in a classroom given in the context of a full attendance course or in a homework activity at a distance learning course. The aim of this paper is two-fold: On one hand to describe the main technical features that make LAVICAD an original fully reusable and reprogrammable tool in signal processing and communication systems courses. On the other hand to show some preliminary academic results obtained with the use of LAVICAD verifying how it improves the level of success.

Changes in shape and size of Robinia pulvinar cortical cells in relation to leaflet movements have been investigated using an image processing system applied to drawings of transverse and longitudinal pulvinar sections. Both the size and shape of cell sections underwent change during movement. The dorsal-left side region of the cortex has been characterized as the extensor region which increases turgor during opening. Morphometric changes occur throughout the cortical motor cells except in the three or four inner layers. K, Cl, S, and Ca distribution in cell walls and protoplasts of inner and outer motor cells have been measured with X-ray microanalysis. The distribution pattern of K and CI shows that these ions are mainly responsible for turgor changes. K and CI were simultaneously depleted in apoplast and protoplast, which suggests that cell walls do not possess a high enough ionic reservoir during Robinia leaflet movements. Ca was always higher in flexor cell walls than in extensor regions of closed pulvini. This fact could be related to a lower ability to extend of flexor cells which underwent fewer morphometric changes during movement.

Background The level of adherence to hepatitis C virus (HCV) treatment is associated with response. High adherence throughout the initial 12 weeks is related to better virological outcomes. Several factors can influence adherence. Purpose To assess HCV treatment adherence and to evaluate the relationship between adherence and rapid (RVR), early (EVR) and sustained virological response (SVR). Material and methods Retrospective observational study of HCV-infected patients receiving pegylated interferon (peg-IFN) + ribavirin (RBV) ± protease inhibitor (PI) from January 2011–December 2013. Demographic and clinical data recorded: age, sex, weight, HIV infection, HCV genotype; quantitative HCV RNA; peg-IFN, RBV and PI doses, frequency and quantities dispensed; psychiatric disorders. Results 183 patients (31.1% women); 14.2% HIV co-infected; 71.2% genotype 1. IL28B CT/TT genotype rate: 33/46. 79.8% were treated with peg-INF + RBV and 20.2% with peg-INF + RBV + PI. 11.7% received reduced RBV/peg-IFN doses. 3.3% required growth factor. RVR: 97.4% (mean reduction: 1.91 log IU/ml). EVR: 46.1%. SVR: 57.3% (genotype 1: 47.1% vs. others: 73.8%; p = 0.011). SVR among PI treated patients: 72.7%. Overall adherence according to quantities dispensed and the Morisky-Green test were 97.35% (95.8% with >80% adherence) and 99.56% (100% > 85% adherence), respectively. Mean adherence according to quantities dispensed at 4 and 12 weeks was 100% and 99.8%, respectively. Sex, HIV co-infection or psychiatric diseases were not associated with lower adherence. No relationship was found between RVR and adherence but the EVR was found to be significantly greater with adherence levels >85% (11.1% vs. 48.3%). Adherence ≥80% was associated with (not significantly) higher rates of SVR (57.7% vs. 50%). Conclusion Adherence >80% is associated with higher cure rates and adherence >85% at 12 weeks is related to greater EVR. No relationship was found between HCV-RNA decrease at 4 weeks and adherence. Neither psychiatric disorders nor HIV co-infection influenced adherence. References and/or Acknowledgements Mathes T, Antoine SL, Pieper D. BMC Infectious Diseases 2014;14:203–16 Lo Re V, Amorosa VK, Localio A, et al . Adherence to hepatitis C virus therapy in HIV/hepatitis C-Coinfected patients. CID 2009;48:186–93 No conflict of interest.

Radiometrically-calibrated Landsat TM data are combined with conventional observations (soil and geology maps, hydrogeological data) to analyze change in the land cover of the Los Monegros region of Aragon, Spain, over the period 1984 - 1997 in order to evaluate the effects of the extension of irrigation on the extent of arable agriculture. Linear spectral unmixing combined with a band ratio mask is used to determine proportions of individual soil types. A change detection technique based on principal component analysis is used in order to identify areas that are most at risk from land degradation processes, principally increased soil erosion and soil salinization, and to explain the ways in which agricultural practices interact with the geomorphological and hydrogeological characteristics of the study are in inducing and maintaining the processes driving change.

In 1989, IBM desiring to establish closer working relationships with libraries particularly with academic libraries established INFORMA as “a forum for current and prospective users of IBM technology in libraries.” INFORMA is directed by a steering committee composed of representatives from institutions currently using IBM technology for library automation, with IBM serving as corporate sponsor. Chair of the committee for the first year was Kaye Gapen, dean of the University of Wisconsin's General Library System, and an IBM consulting scholar. Jordan Scepanski, director of libraries and learning resources, California State University at Long Beach, is the current chair.

Cerdanya is a Neogene half-graben basin that lies over the Palaeozoic rocks of the Eastern Pyrenean Axial Zone. Subvertical fault scarps bound the half-graben at the southern and southeastern margins, but Neogene sediments may directly overlap Palaeozoic rocks in the northern margin. Vertical electrical soundings show that the Miocene sequence reaches a maximum thickness of over 700 m and that fine-grained lacustrine deposits from the central part of the basin grade to coarser fluvial deposits toward the margins. Macro- and micro-structural data analyzed in Cerdanya and other related Neogene basins, such as Rossello, Confient, Capcir and Seu d'Urgell, suggest that they formed as a consequence of transtensile motion along an old northeastern-trending fault. The stress situation favoured sinistral movements along east-trending faults.

Procedures utilisees pour l'evaluation de l'efficacite d'un cours de bibliotheconomie. Trois strategies d'evaluation ont ete utilisees. Des procedures d'evaluation automatisees ont ete appliquees