Search results for "FAD"
showing 10 items of 292 documents
A Novel Amplify-and-Forward Relay Channel Model for Mobile-to-Mobile Fading Channels under Line-of-Sight Conditions
2021
In this chapter, we have proposed a new flexible M2M amplify-and-forward relay fading channel model under LOS propagation conditions. The novelty in the model is that we have considered the LOS components in both transmission links, i.e., the direct link between the source mobile station and the destination mobile station as well as the link via the mobile relay. By analogy with multiple scattering radio propagation channels, we have developed the MLSS fading channel as a second-order scattering channel, where the received signal comprises the single and double scattered components. Furthermore, the flexibility of the MLSS fading channel model comes from the fact that it can be reduced to d…
A study on the statistical properties of double hoyt fading channels
2009
This paper deals with a study on the statistical properties of narrowband amplify-and-forward relay fading channels for Hoyt multipath propagation environments. We consider the basic radio link topology, where only one fixed relay station is used for the amplification. In this case, the envelope of the signal received over the overall multipath channel is modeled by the so-called double Hoyt fading process. Considering this multipath propagation channel model, analytical expressions for the first and second order statistics are provided. Specifically, the mean value, variance, probability density function (PDF), level-crossing rate (LCR), and average duration of fades (ADF) of double Hoyt p…
The design of sum-of-cisoids rayleigh fading channel simulators assuming non-isotropic scattering conditions
2010
In this letter, we introduce the Riemann sum method (RSM) as an effective tool for the design of sum-of-cisoids (SOC) simulators for narrowband mobile Rayleigh fading channels under non-isotropic scattering conditions. We compare the performance of the RSM with that of the generalized method of equal areas (GMEA) and the Lp-norm method (LPNM), which were until now the only methods available for the design of SOC simulators for non-isotropic scattering channels. The obtained results indicate that the RSM is better suited than the GMEA and the LPNM to emulate the channel's autocorrelation function (ACF), whereas the latter two methods are more precise regarding the approximation of the envelo…
Nuevos estándares de calidad de linfadenectomía D3 en la escisión completa del mesocolon tras la hemicolectomía derecha
2022
Introducción y objetivo. Los estándares de calidad anatomopatológica de escisión total del mesorrecto y escisión completa de mesocolon se basan en parámetros anatomoquirúrgicos constantes y están claramente definidos. Mediante estos estándares se ha podido relacionar la calidad de la pieza quirúrgica con el aumento de la supervivencia. La técnica quirúrgica de Linfadenectomia D3 (LD3) en la hemicolectomía derecha se basa en la disección e incorporación a la pieza quirúrgica del tejido linfograso del tronco gastrocólico de Henle y del tronco quirúrgico de Gillot. Numerosos estudios destacan la necesidad de establecer estándares de calidad anatomopatológicos de LD3 hasta el momento no descrit…
Respostas mecânicas da musculatura do joelho de bodyboarders de alto nível durante o desempenho
2015
INTRODUCTION: bodyboarding is a kind of surfing that has been growing very rapidly over the last decade and has now developed into one of the fastest growing water sports in the world.OBJECTIVES: evaluate the effects of fatigue on rectus femoris RF, vastus lateralis VL and vastus medialis VM and biceps femoris BF and semitendinosus ST during a high-level bodyboard competition using tensiomyography TMG.METHODS: subjects were 11 highly experienced years of practice: 15, SD=4.65 male bodyboarders age: 28.17, SD=2.89, body weight: 74.83, SD=6.13kg; height: 179.25, SD=3.93cm; BMI: 23.29, SD=1.81 participating in the final of the 2010 Spanish championship.RESULTS: the fatigue is especially eviden…
FLUMO: FLexible Underwater MOdem
2019
The last years have seen a growing interest in underwater acoustic communications because of its applications in marine research, oceanography, marine commercial operations, the offshore oil industry and defense. High-speed communication in the underwater acoustic channel has been challenging because of limited bandwidth, extended multipath, refractive properties of the medium, severe fading, rapid time variation and large Doppler shifts. In this paper, we show an implementation of a flexible Software-Defined Acoustic (SDA) underwater modem, where modulation parameters are completely tunable to optimize performance. In particular, we develop the system architecture following two key ideas. …
«La princesa i el pèsol» (ATU 704): de les reescriptures escolars a la construcció identitària
2018
A partir del conte d’Andersen «La princesa i el pèsol», s’aborden qüestions que afecten el sentit i difusió d’un text que forma part del cànon de contes clàssics, objecte de pràctiques discursives diverses. En primer lloc, la interpretació de la sensibilitat extrema de la seua protagonista i la reflexió sobre el possible missatge misògin del relat. En aquest sentit, es tracta la reescriptura dels contes de fades proposada per la crítica feminista i l’aparició de nous contes metaficcionals que dialoguen intertextualment amb els clàssics. S’hi aborda la presència i l’ús actual de la figura dels contes de princeses en l’àmbit escolar. En el context de la «glocalització», que dona visibilitat a…
Documenting the light sensitivity of Spanish Levantine rock art paintings
2015
[EN] A case study to evaluate the use of microfading spectrometry (MFS) for the study of colored systems found in prehistoric rock art paintings was conducted in the Cova Remígia rock-shelter, Castellón (Spain). This rock shelter is part of the rock art sites of the Mediterranean basin on the Iberian Peninsula included in UNESCO s World Heritage List. Some of the paintings belonging to this group are exposed to environmental factors including natural daylight, wind and rain, depending on the time of the day and the season of the year. Therefore, their preservation is a major concern to stakeholders and researchers responsible for protecting and studying these prehistoric paintings. The expe…
Distribution and depletion of sulfadiazine after a multiple per os dosing in gilthead sea bream (Sparus aurata) fed two different diets
2013
The distribution and depletion profile of sulfadiazine (SDZ) were investigated in gilthead sea bream (Sparus aurata) fed on fish oil (FO) or plant oil-based (PO) diets. Fish averaging 230 g were given medicated feed containing 25 mg SDZ kg-1 fish for 5 days at 24-26°C. Blood and muscle plus skin were sampled on days 1, 3, 5, 6, 8 and 9. Differences in plasma and fillet SDZ levels between the two groups were statistically insignificant. The maximum drug concentrations in plasma were 3.2 ± 1.9 μg mL-1 and 2.9 ± 1.2 μg mL-1 in the PO and FO groups, respectively. In post-medicated samples depletion rapidly reached concentrations close to the level of quantification at 72 h post medication. With…
Traditional and experimental floating fish aggregating devices in the Gulf of Castellammare (NW Sicily): Results from catches and visual observations
1999
Floating fish aggregating devices (FADs) have long been used to attract fish in NW Sicily since antiquity. Recently, a number of changes have been made to the type of material employed to construct FADs, with the aim of increasing their effectiveness. In this paper we compare the catches made at eight experimental floating FADs (polypropylene ropes frayed at the ends) with those obtained at eight traditional FADs in the Gulf of Castellammare. A total of 672 samples were collected during summer and autumn in 1995 and 1996 at the 16 FADs using a surrounding net. Visual observations of fishes associated with the FADs were also conducted to obtain qualitative information about the spatial distr…