46 research outputs found

    Residential wireless interfaces virtualization: a feasibility study

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    This paper investigates the possibility of virtualizing and distributing the functionality that runs on top of residential wireless communications. Specifically, we propose, describe and test a solution that transports USB communications to remote locations, for scenarios in which the in-home wireless interfaces are consumed at the server side through this type of general-purpose and widely used interfaces. We frame this study in a general architecture by which Software Defined Networking (SDN) and Network Functions Virtualization (NFV) bring economies of scale, flexibility and programmability to residential Internet of Things (IoT) environments. As a result of our tests, we prove the feasibility of the remote presence of the IoT systems through the Universal Serial Bus (USB) tunnels, and we obtain approximate bandwidth measurements that serve as a hint on the type of services that can be offloaded to the cloud. For those functionalities that would need more bandwidth, we propose to embed a lightweight virtualization environment in home and to execute in it part of the virtualized components, something that is in line with the recent fog computing approaches

    Wireless sensor network-based system for measuring and monitoring road traffic

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    Nowadays, the measure and classification of vehicles in road traffic is accomplished by inductive loops placed under the pavement. These inductive loops allow monitoring vehicle passing by means of different configurations which provide us a number of data in order to control several parameters of the traffic (vehicle speed, traffic congestion and traffic accidents, between others). The major objective of this paper is to analysis an alternative to magnetic loops: the Wireless Sensor Networks. Firstly, a state of the art about road traffic control is described. Secondly, an alternative system based on Wireless Sensor Networks is analyzed. Network architecture for this WSN will be specified. It is not a trivial task because of the hard constraints of the small devices which compose the WSNs. In previous papers [1], we have proposed a methodology that facilitates the WSNs design for supporting real time applications such as traffic control applications. This design methodology has been used in order to obtain a WSN that reaches the real time requirements of a monitoring traffic application for intelligent roads. In the short term, the aim is to define a simulation model based on the designed WSN. To conclude, we have introduced a section about possible future directions in the smart roads field

    Runtime variability for dynamic reconfiguration in wireless sensor network product lines

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    Runtime variability is a key technique for the success of Dynamic Software Product Lines (DSPLs), as certain application demand reconfiguration of system features and execution plans at runtime. In this emerging research work we address the problem of dynamic changes in feature models in sensor networks product families, where nodes of the network demand dynamic reconfiguration at post-deployment time

    Up2B2: Playing English grammar games at the B2 level

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    The study presented herein is framed within the Mobile Assisted Language Learning (MALL) approach and presents the results from the use of an original mobile app, developed by the research team, on the part of 73 students. The app prototype consists of multiple choice questions and answers that assess varied aspects of the grammar, vocabulary and use of English at level B2 according to the Common European Framework of Reference for Languages (CEFRL). The application presents motivating gamification components that aim at enhancing students’ participation and regular use of the game. Some of these gamification features are response time, use of competition and training tests, and a score ranking based on nicknames. The study uses different indexes in order to describe the use of the platform and qualitative and quantitative indicators to reach positive conclusions related to students’ increased motivation and improvement in their grammar and vocabulary competence levels

    QoS in wireless sensor networks: survey and approach

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    A wireless sensor network (WSN) is a computer wireless network composed of spatially distributed and autonomous tiny nodes -- smart dust sensors, motes -, which cooperatively monitor physical or environmental conditions. Nowadays these kinds of networks support a wide range of applications, such as target tracking, security, environmental control, habitat monitoring, source detection, source localization, vehicular and traffic monitoring, health monitoring, building and industrial monitoring, etc. Many of these applications have strong requirements for end-to-end delay and losses during data transmissions. In this work we have classified the main mechanisms that have been proposed to provide Quality of Service (QoS) in WSN at Medium Access Control (MAC) and network layers. Finally, taking into account some particularities of the studied MAC- and network-layer protocols, we have selected a real application scenario in order to show how to choose an appropriate approach for guaranteeing performance in a WSN deployed application

    Aprendizaje asistido por dispositivos móviles: UP2B2

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    Este trabajo se enmarca en el enfoque denominado Mobile Assisted Language Learning (MALL) y presenta un prototipo de juego de preguntas y respuestas de opción múltiple que revisa la gramática, el vocabulario y el uso de la lengua inglesa del nivel B2 (Marco Común Europeo de Referencia para las Lenguas-MCERL). La aplicación se caracteriza por presentar una componente de gamificación cuyo objetivo es motivar a los estudiantes a que la usen mediante un sistema de puntuación que los sitúa en un ranking global y que considera tanto los aciertos de cada uno como el tiempo en completar los tests. Se definen distintos índices para la monitorización de la plataforma e indicadores tanto de carácter cualitativo como cuantitativo para la medida de los resultados. ABSTRACT This work is framed within the approach called Mobile Assisted Language Learning (MALL) and presents a game prototype consisting of multiple choice questions and answers that assess the grammar, vocabulary and the use of the English language at level B2 according to the Common European Framework of Reference for Languages. The application is characterized by a strong gamification component that aims to motivate the students using it. Therefore, response time, correct answers and a ranking with the punctuation centre the most prominent aspects related to its playability. Different indexes are defined for the monitoring of the platform as well as qualitative and quantitative indicators for the study of the results

    Overall and cause-specific excess mortality in HIV-positive persons compared with the general population: Role of HCV coinfection

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    We aimed to estimate overall and cause-specific excess mortality of HIV-positive patients compared with the general population, and to assess the effect of risk factors.We included patients aged >19 years, recruited from January 1, 2004 to May 31, 2014 in Cohort of the Spanish Network on HIV/AIDS Research. We used generalized linear models with Poisson error structure to model excess mortality rates.In 10,340 patients, 368 deaths occurred. Excess mortality was 0.82 deaths per 100 person-years for all-cause mortality, 0.11 for liver, 0.08 for non-AIDS-defining malignancies (NADMs), 0.08 for non-AIDS infections, and 0.02 for cardiovascular-related causes. Lower CD4 count and higher HIV viral load, lower education, being male, and over 50 years were predictors of overall excess mortality. Short-term (first year follow-up) overall excess hazard ratio (eHR) for subjects with AIDS at entry was 3.71 (95% confidence interval [CI] 2.66, 5.19) and 1.37 (95% CI 0.87, 2.15) for hepatitis C virus (HCV)-coinfected; medium/long-term eHR for AIDS at entry was 0.90 (95% CI 0.58, 1.39) and 3.83 (95% CI 2.37, 6.19) for HCV coinfection. Liver excess mortality was associated with low CD4 counts and HCV coinfection. Patients aged ≥50 years and HCV-coinfected showed higher NADM excess mortality, and HCV-coinfected patients showed increased non-AIDS infections excess mortality.Overall, liver, NADM, non-AIDS infections, and cardiovascular excesses of mortality associated with being HIV-positive were found, and HCV coinfection and immunodeficiency played significant roles. Differential short and medium/long-term effects of AIDS at entry and HCV coinfection were found for overall excess mortality.The RIS cohort (CoRIS) is supported by the Instituto de Salud Carlos III through the Red Temática de Investigación Cooperativa en Sida (RD06/006 and RD12/0017/0018) as part of the Plan Nacional R+D+I and cofinanced by ISCIII-Subdirección General de Evaluación y el Fondo Europeo de Desarrollo Regional (FEDER)S

    Pervasive surveillance-agent system based on wireless sensor networks: design and deployment

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    Nowadays, proliferation of embedded systems is enhancing the possibilities of gathering information by using wireless sensor networks (WSNs). Flexibility and ease of installation make these kinds of pervasive networks suitable for security and surveillance environments. Moreover, the risk for humans to be exposed to these functions is minimized when using these networks. In this paper, a virtual perimeter surveillance agent, which has been designed to detect any person crossing an invisible barrier around a marked perimeter and send an alarm notification to the security staff, is presented. This agent works in a state of 'low power consumption' until there is a crossing on the perimeter. In our approach, the 'intelligence' of the agent has been distributed by using mobile nodes in order to discern the cause of the event of presence. This feature contributes to saving both processing resources and power consumption since the required code that detects presence is the only system installed. The research work described in this paper illustrates our experience in the development of a surveillance system using WNSs for a practical application as well as its evaluation in real-world deployments. This mechanism plays an important role in providing confidence in ensuring safety to our environment

    The avoidance of G-CSF and the addition of prophylactic corticosteroids after autologous stem cell transplantation for multiple myeloma patients appeal for the at-home setting to reduce readmission for neutropenic fever

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    Background Autologous stem cell transplantation (ASCT) remains the standard of care for young multiple myeloma (MM) patients; indeed, at-home ASCT has been positioned as an appropriate therapeutic strategy. However, despite the use of prophylactic antibiotics, neutropenic fever (NF) and hospital readmissions continue to pose as the most important limitations in the outpatient setting. It is possible that the febrile episodes may have a non-infectious etiology, and engraftment syndrome could play a more significant role. The aim of this study was to analyze the impact of both G-CSF withdrawal and the addition of primary prophylaxis with corticosteroids after ASCT. Methods Between January 2002 and August 2018, 111 MM patients conditioned with melphalan were managed at-home beginning +1 day after ASCT. Three groups were established: Group A (n = 33) received standard G-CSF post-ASCT; group B (n = 32) avoided G-CSF post-ASCT; group C (n = 46) avoided G-CSF yet added corticosteroid prophylaxis post-ASCT. Results The incidence of NF among the groups was reduced (64%, 44%, and 24%; P2 (OR 6.1; P = 0.002) and G-CSF avoidance plus corticosteroids (OR 0.1; P60 years (OR 14.6; P = 0.04) and G-CSF avoidance plus corticosteroids (OR 0.07; P = 0.05). Conclusions G-CSF avoidance and corticosteroid prophylaxis post ASCT minimize the incidence of NF in MM patients undergoing at-home ASCT. This approach should be explored in a prospective randomized clinical trial
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