Uso del conocimiento estadístico de la señal para la mejora de la velocidad de convergencia de los algoritmos adaptativos de gradiente

This work deals with the use of previous or colateral information to improve the behaviour of adaptive algorithms. The study is made on gradient-based methods due to the relatively simple and good performances that they use to exhibit. This paper shows that the complete knowledge of the data at the input of the adaptive filter (and in consequence of its autocorrelation matrix and its inverse) can be used to modify the classic L. M.S. algorithm leading to better expressions for the gradient and a new adaptive 'step size'. Finally, the description is completed with the comparison between the variation ranges and a natural generalization of 'step size' parameter is obtained.Peer ReviewedPostprint (published version

Known input power spectrum in adaptive L.M.S. and A.G. algorithms

This work deals with the use of previous or colateral information to improve the behaviour of adaptive algorithms. The study is made on gradient-baseq methods due te the relatively simple and good performances that they use to exhibit. This paper shows that the complete knowledge of the data at the input of the adaptive filter (and in consequence of its autocorrelation matrix and its inverse) can be used to modify the classic L.M.S. algorithm leading to new expressions for the gradient and for the optimum 1step size 1 , alternative, in sorne cases, to the Powell expression. Finally, the description is completed with the comparison between the variation ranges and VLSI implementation cost for this two optimum 1 step size 1 values anda natural generalization set of parameter is obtained.Peer ReviewedPostprint (published version

Known Input Power Spectrum in Adaptive L.M.S. and A. G. Algorithms

This work deals with the use of previous or colateral information to improve the behaviour of adaptive algorithms. The study is made on gradient-baseq methods due te the relatively simple and good performances that they use to exhibit. This paper shows that the complete knowledge of the data at the input of the adaptive filter (and in consequence of its autocorrelation matrix and its inverse) can be used to modify the classic L.M.S. algorithm leading to new expressions for the gradient and for the optimum 1step size 1 , alternative, in sorne cases, to the Powell expression. Finally, the description is completed with the comparison between the variation ranges and VLSI implementation cost for this two optimum 'step size' values anda natural generalization set of parameter is obtained.Peer ReviewedPostprint (published version

Constant variance transversal filtering for adaptive channel equalization

Peer ReviewedPostprint (published version

Plan de Implementación Regional para Pesquerías Demersales de las Islas Baleares (Mediterráneo Occidental)

De acuerdo con la Política Pesquera Común (PPC), todos los stocks pesqueros europeos deberían situarse en un estado que les permita producir en base al Rendimiento Máximo Sostenible (RMS) en el año 2020 como tarde. El proyecto Myfish, financiado por el Séptimo Programa Marco de la UE, tuvo como objetivo construir un marco operacional para la implementación del objetivo del RMS como herramienta para la futura gestión de stocks pesqueros europeos. Este informe presenta el Plan de Implementación Regional para pesquerías demersales de las Islas Baleares (Mediterráneo Occidental) desarrollado en el marco de Myfish en estrecha colaboración con los principales stakeholders locales. El estudio pretende ser de utilidad como primer paso hacia el diseño de planes de gestión pesquera en el área de estudio y un ejemplo práctico de la implementación de la PPC en el Mediterráneo

Reproductive strategies of common dentex Dentex dentex: management implications

The common dentex Dentex dentex is an iconic endangered species in the Mediterranean, where it is a target species that is sought after for small-scale, recreational and spearfishing fisheries. The reproductive biology of D. dentex in the natural environ¬ment is poorly known; therefore, the reproductive strategy of the species was assessed through a combination of reproductive traits and growth characteristics (estimated from length-at-age data), the size/age of sexual maturity and the energetic dynamics. A total of 358 wild fish, ranging in total length (LT) from 19 to 84.7 cm, was sampled at Mallorca Island (Western Mediterranean) from March 1996 to June 1999. The sex ratio was skewed towards females (1.361); however, the length composition was not different between sexes (p = 0.551). Three young immature individuals (< 28 cm LT, 0.8% individuals) were rudimentary hermaphrodites, offering support for classification as a late gonochoristic species. The age composition, determined based on the sagittal otolith, ranged from 0 to 26 years (yr). The von Bertalanffy growth function did not differ between sexes (F = 2.58, p = 0.762): L∞ =76.581 cm, K = 0.127 yr-1, t0 = -2.335 in a combined function. The maturity ogives for size and age showed that females achieved 50% maturity at 34.922 cm LT and 3.3 yr, and males, at 33.812 cm LT and 2.5 yrs. The onset of annual ripening took place in December, whereas vitellogenesis occurred from February to April. The spawning peak was in April and May for both males and females. A generalised linear model (GLM) showed that female size did not significantly affect the spawning season, whilst the seasonal component affected both the onset and end of spawning (GLM, p < 0.005). The gonadosomatic index (IG), hepatosomatic index (IH) and relative condition index (KR) varied significantly with the reproductive season for females, and IG varied for males. The microscopic observation of the gonads showed that fecundity is likely determinate, with an asynchronous oocyte development before spawning and a clear ovarian bimodal organization after the onset of spawning. The oocyte density variance of 85% was explained by the oocyte diameter, which also offered support for the trait of determinate fecundity. Female weight explained 84% of the observed variance for fecundity. Liver storage seemed to be the primary source of energy for maturity, which suggests a combination of capital and income breeding. The results suggested a reproductive strategy of type A, with balanced trade-offs be¬tween survival, growth and reproduction. At present, no management measures are being directed to D. dentex; herein, we suggest a minimum landing size of 35 cm LT to ensure a higher proportion of larger fish to preserve the stockVersión del editor0,568

Reduced Antioxidant Response of the Fan Mussel Pinna nobilis Related to the Presence of Haplosporidium pinnae

The endemic fan mussel (Pinna nobilis) in the Mediterranean Sea is at high risk of disappearance due to massive mortality events. The aim of the study was to evaluate the antioxidant response of P. nobilis collected in the Balearic Islands (Western Mediterranean) before and after the mass mortality event. Individuals collected before (between 2011 and 2012) and after (between 2016 and 2017) the event were analyzed by histological, molecular, and biochemical methods to compare pathogenic loads and biochemical responses. All the individuals collected during 2016–2017 presented symptoms of the disease and were positive for Haplosporidium pinnae, while acid-fast bacteria or/and Gram-negative bacteria were detected in some individuals of both sampling periods. The activities of the antioxidant enzymes catalase and superoxide dismutase in the gills were significantly lower in P. nobilis a ected with the parasite compared to those in the asymptomatic ones, while levels of malondialdehyde, as an indicator of lipid peroxidation, were higher in infected individuals. When analyzing the di erential e ects of H. pinnae and Mycobacterium sp. on P. nobilis, it was observed that significant e ects on biomarkers were only observed in the presence of H. pinnae. Co-infection of P. nobilis by H. pinnae with other pathogens such as Mycobacterium sp. constitutes a serious problem due to its high mortality rate in the Balearic Island waters. This concerning situation for P. nobilis is favored by a reduction in antioxidant defenses related to H. pinnae infection that induces oxidative stress and cell damage.En prens

Pla d’Implementació Regional per a Pesqueries Demersals de les Illes Balears (Mediterrani Occidental)

D’acord amb la Política Pesquera Comuna (PPC), tots els stocks de peixos europeus haurien de situarse en l’estat que els permetés produir en base al Rendiment Màxim Sostenible (RMS) a l’any 2020 com a màxim. El projecte Myfish, finançat pel Sèptim Programa Marc de la UE, va tenir com a objectiu construir un marc operacional per a la implementació de l’objectiu RMS com a eina per a la futura gestió d’stocks pesquers europeus. Aquest informe presenta el Pla d’Implementació Regional (PIR) per a pesqueries demersals de les Illes Balears (Mediterrani Occidental) desenvolupat en el marc de Myfish en estreta col.laboració amb els principals stakeholers locals. L’estudi pretén ser d’utilitat com a primera passa cap al disseny de plans de gestió pesquera a l’àrea d’estudi i un exemple pràctic d’implementació de la PPC al Mediterrani