Understanding the impact of line-of-sight in the ergodic spectral efficiency of cellular networks

In this paper we investigate the impact of lineof-sight (LoS) condition in the ergodic spectral efficiency of cellular networks. To achieve this goal, we have considered the kappa-mu shadowed model, which is a general model that provides an excellent fit to a wide set of propagation conditions. To overcome the mathematical complexity of the analysis, we have split the analysis between large and small-scale effects. Building on the proposed framework, we study a number of scenarios that range from heavily-fluctuating LoS to deterministic-LoS. Finally, we shed light on the interplay between fading severity and spectral efficiency by means of the amount of fading.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

A closed‐form expression for the coverage of cellular systems under Hoyt (Nakagami-q) fading.

Política de acceso abierto tomada de:https://digital-library.theiet.org/files/Author_self-archiving_policy.pdfA simple closed-form expression is provided for the coverage probability of cellular systems under Hoyt (Nakagami-q) fading, which models fading scenarios more severe than Rayleigh. The accuracy of the proposed framework is validated through Monte Carlo simulation

Further Improvements in SOVA for High-Throughput Parallel Turbo Decoding.

In this letter, we present two mechanisms based on soft-output Viterbi algorithm (SOVA) technique that achieve a performance close to maximum a-posteriori (MAP) decoding. First, we propose a new technique called alternating direction SOVA, which allows for improving the performance of SOVA in similar terms as bidirectional SOVA while barely affecting the area complexity. Then, we introduce the idea of parallel turbo decoding based on path metric/state border exchange. Unlike other techniques, overlapping between adjacent subblocks is not required, thus reducing the decoding latency dramatically. We evaluate their performance in the context of 3GPP-LTE, showing that the combination of both mechanisms achieves a BER performance close to parallel MAP decoding while having a lower complexit

Adaptive SOVA for 3GPP-LTE Receivers

Turbo codes are extensively used in wireless communication systems and have been adopted as the channel coding scheme for next generation cellular standards. The complexity associated with the decoding process is an important issue. In this paper, we propose an adaptive Soft Output Viterbi Algorithm (adSOVA) based turbo decoder which is proved to reduce complexity without experiencing a degradation in error correction performance. The proposed adSOVA is evaluated in a long term evolution (LTE) downlink scenario and compared with the SOVA and the Max-Log-MAP algorithms. Simulation results show that a complexity reduction of 40% can be achieved with respect to the conventional SOVA with no BLock Error Rate (BLER) degradatio

Consideraciones para una óptima salud en el puesto de trabajo

La ergonomía desempeña un papel creciente en la solución del problema de rehabilitación de personas que en una u otra medida han perdido la capacidad de trabajo; también se estudian las aptitudes y peculiaridades psíquicas y físicas de las personas de edad avanzada y de aquellos individuos considerados como trabajadores especialmente sensibles. Por ello los principios ergonómicos se aplican para optimizar las condiciones de trabajo en relación al bienestar de la persona, su salud y su seguridad, sin olvidar la eficiencia tecnológica y económica. El abordaje de los factores de riesgo que intervienen en la producción de problemas de espalda en los profesionales, incluye al ser humano en sentido integral, desde el punto de vista físico, psicológico y social. En nuestro trabajo nos vamos a centrar en los factores físicos principalmente, destacaremos la adopción de posturas forzadas, movimientos bruscos, así como la inadecuada preparación física y el sedentarismo en una profesión sanitaria, la del técnico en transporte sanitario. Pero no debemos dejar de hacer mención de los otros puntos de vista: el estrés laboral, el apremio de tiempo, que da lugar a que se trabaje con mayor ritmo y no precisamente adoptando posiciones correctas. Aspectos relacionados con la satisfacción laboral también acentúan el estrés y la tensión muscular. La ausencia de una formación preventiva adecuada respecto a técnicas de movilización de enfermos. La falta de personal en los centros de trabajo, que implican una sobrecarga; el deficiente o nulo uso de medios mecánicos adecuadamente diseñados desde el punto de vista ergonómico.Ergonomics plays an increasing role in solving the problem of rehabilitation of people have lost the ability to work, it also examines the skills and mental and physical peculiarities of the elderly and those individuals considered workers are particularly sensitive. Therefore apply ergonomic principles to optimize the conditions of work for the welfare of the person, their health and safety, not forgetting the technological and economic efficiency. The approach of the risk factors involved in the production of back problems in the professionals, including the human being in integral sense from the standpoint of physical, psychological and social. In our work we focus mainly on physical factors, we will highlight the adoption of awkward postures, sudden movements, as well as inadequate physical fitness and physical inactivity in a health profession, the technician in health transport. But we must not fail to mention the other points of view: work stress, time pressure, which leads you to work with greater pace and not just taking proper positions. Aspects related to job satisfaction also accentuate stress and muscle tension. The absence of adequate preventive training on techniques of mobilization of patients. The lack of staff in the workplace, resulting in an overload, the poor or no use of properly designed mechanical means from the ergonomic standpoint.peerReviewe

EEG signal processing in mi-bci applications with improved covariance matrix estimators

Article number 8688582n brain–computer interfaces (BCIs), the typical models of the EEG observations usually lead to a poor estimation of the trial covariance matrices, given the high non-stationarity of the EEG sources. We propose the application of two techniques that significantly improve the accuracy of these estimations and can be combined with a wide range of motor imagery BCI (MI-BCI) methods. The first one scales the observations in such a way that implicitly normalizes the common temporal strength of the source activities. When the scaling applies independently to the trials of the observations, the procedure justifies and improves the classical preprocessing for the EEG data. In addition, when the scaling is instantaneous and inde pendent for each sample, the procedure particularizes to Tyler’s method in statistics for obtaining a distribution free estimate of scattering. In this case, the proposal pro vides an original interpretation of this existing method as a technique that pursuits an implicit instantaneous power-normalization of the underlying source processes. The second technique applies to the classifier and improves its performance through a convenient regularization of the features covariance matrix. Experimental tests reveal that a combination of the proposed techniques with the state-of-the-art algorithms for motor-imagery classification provides a significant improvement in the classification results.Ministerio de Economía y Competitividad ( España) TEC2017-82807-

Effects of the Combination of Music Therapy and Physiotherapy in the Improvement of Motor Function in Cerebral Palsy: A Challenge for Research

Background: There are different therapeutic strategies such as physiotherapy and music therapy for the treatment of cerebral palsy. Intervention protocols using both therapies to unify the measurement of motor function have not been investigated. Aims and scope: To summarize the effects of the treatment of cerebral palsy through the use of both for the improvement of motor function, analyse the challenges encountered, and submit proposals for improving them. Methods: The systematic review was conducted following PRISMA guidelines and registered in the PROSPERO database (CRD42020162493). Clinical trials that described the results obtained in terms of motor function through physiotherapy and music therapy were included. Results: Eight clinical trials with 234 participants were considered with a significant improvement in motor function. Results of meta-analysis suggested improvements in gait velocity in favour of the control group for cerebral palsy (mean differences = 0.03; 95% confidence interval = 0.01, 0.04, p = 0.001; I-2 = 97%). However, high heterogeneity was identified in the meta-analysis due to the small number of studies included. Conclusions: The combination can be effective in subjects with cerebral palsy to improve motor function, although due to the diversity of studies analysed, it is complex to extrapolate results.This research was funded by the Department of Nursing and Physiotherapy (University of Cadiz)

Joint Distribution of Distance and Angles in Finite Wireless Networks

Directional beamforming will play a paramount role in 5G and beyond networks in order to combat the higher path losses incurred at millimeter wave bands. Appropriate modeling and analysis of the angles and distances between transmitters and receivers in these networks are thus essential to understand performance and limiting factors. Most existing literature considers either infinite and uniform networks, where nodes are drawn according to a Poisson point process, or finite networks with the reference receiver placed at the origin of a disk. Under either of these assumptions, the distance and azimuth angle between transmitter and receiver are independent, and the angle follows a uniform distribution between $0$ and $2\pi$. Here, we consider a more realistic case of finite networks where the reference node is placed at any arbitrary location. We obtain the joint distribution between the distance and azimuth angle and demonstrate that these random variables do exhibit certain correlation, which depends on the shape of the region and the location of the reference node. To conduct the analysis, we present a general mathematical framework which is specialized to exemplify the case of a rectangular region. We then also derive the statistics for the 3D case where, considering antenna heights, the joint distribution of distance, azimuth and zenith angles is obtained. Finally, we describe some immediate applications of the present work, including the analysis of directional beamforming, the design of analog codebooks and wireless routing algorithms.Comment: 14 pages, 14 figure

Aplicación De Un Modelo Basado En La Gestión Del Conocimiento Para Mejorar El Nivel De Aprovechamiento De Las Tic. Estudio De Caso En Una Pyme Mexicana

A very dynamic environment and constant technological advances are surrounding small and medium-sized enterprises (SMEs) in their commercial activities. The business context is becoming increasingly complex, as there are continually numerous aspects related to the application of knowledge, both financial, legal, organizacional and technological. In relation to the application of information and communication technologies (ICT), SMEs need to acquire and apply knowledge correctly to obtain the best use of these technologies in their business processes. Taking this scenario into account, the objective of this paper is to present the case study on the application of a conceptual model based on knowledge management (KM) to improve the level of use of ICT in the business processes of mexican SMEs. The model was applied in an SME of the commercial sector. The results obtained are exposed, as well as the conclusions and future perspectives of the work developed

Use of Iontophoresis with Corticosteroid in Carpal Tunnel Syndrome: Systematic Review and Meta-Analysis

Background: Carpal tunnel syndrome is a neuropathy that affects the median nerve. The aim of this review is to synthesize the evidence and perform a meta-analysis on the effects of iontophoresis in people with carpal tunnel syndrome. Methods: The search was carried out using PubMed, Web of Science, Scopus, CINHAL Complete, Physiotherapy Evidence Database, and SciELO. The methodological quality was evaluated using PEDro. A standardized or mean difference meta-analysis (Hedge’s g) using a random-effects model was calculated. Results: Seven randomized clinical trials using iontophoresis for electrophysiological, pain, and functional outcomes were included. The mean of PEDro was 7/10. No statistical differences were obtained for the median sensory nerve conduction velocity (SMD = −0.89; p = 0.27) or latency (SMD = −0.04; p = 0.81), motor nerve conduction velocity (SMD = −0.04; p = 0.88) or latency (SMD = −0.01; p = 0.78), pain intensity (MD = 0.34; p = 0.59), handgrip strength (MD = −0.97; p = 0.09), or pinch strength (SMD = −2.05; p = 0.06). Iontophoresis only seemed to be superior in sensory amplitude (SMD = 0.53; p = 0.01). Conclusions: Iontophoresis did not obtain an enhanced improvement compared to other interventions, but no clear recommendations could be made due to the limited number of included studies and the heterogeneity found in the assessment and intervention protocols. Further research is needed to draw sound conclusions.15 página