THE STABILITY OF β-CAROTENE IN MANGO NECTAR

THE STABILITY OF β-CAROTENE IN MANGO NECTA

Design issues for the VLSI implementation of universal approximator fuzzy systems

Comunicación presentada al "CSCC'99" celebrado en Atenas en Julio de 1999.Several VLSI realizations of fuzzy systems have been proposed in the literature in the recent years. They employ analog or digital circuitry, offering more or less programmability, implementing different inference methods, with different types of membership functions as well as different antecedents’ connectives. This paper centers this wide design space by fixing several parameters that allow efficient VLSI implementations of programmable fuzzy systems featuring first, second and third order accurate approximation. Hardware requirements are discussed and compared from the point of view of approximation capability or precision, thus attempting to a formalization that has never been applied before to the field of fuzzy hardware.This work has been partially supported by the Spanish CICYT Project TIC98-0869.Peer reviewe

Influence of the synthesis process on the features of Y2O3-stabilized ZrO2 powders obtained by the sol–gel method

Y2O3-stabilized ZrO2 (YSZ) powders have been prepared by the sol–gel method using different synthesis parameters. Specifically, zirconium n-propoxide was dissolved in propanol at pH 0.5 or 5 (provided by HNO3), with or without acetic acid in the hydrolysis medium. Subsequently, the YSZ powders obtained by gelation and drying of these solutions was characterized using scanning and transmission electron microscopies, X-ray diffractometry, and N2-adsorption. Compacts made from these YSZ powders which were then sintered were also analyzed. It was found that the pH of the hydrolysis medium has a notable influence on the microstructure, morphology, color, crystallinity, and sintering behavior process of these YSZ sol–gel powders. It was also found that the use of acetic acid also affects the YSZ powder features, and results in compacts with higher residual porosity after sintering. Finally, the compacts prepared from the YSZ powders obtained at pH 5 and without acetic acid exhibit the greatest sinterabilityFil: Mamana, Nadia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Física de Rosario. Universidad Nacional de Rosario. Instituto de Física de Rosario; ArgentinaFil: Díaz Parralejo, Antonio. Universidad de Extremadura. Badajoz; EspañaFil: Ortiz, Angel L. Universidad de Extremadura. Badajoz; EspañaFil: Sánchez Bajo, Florentino. Universidad de Extremadura. Badajoz; EspañaFil: Caruso, Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Física de Rosario. Universidad Nacional de Rosario. Instituto de Física de Rosario; Argentin

Expectativas y opiniones de patronos de profesionales en las ciencias agrícolas

Ninety-four employers of agricultural science graduates were interviewed as to their opinion about the future of professional agricultural careers, the knowledge and capabilities they required in their professional employees, and the degree to which the agricultural science graduates possessed these attributes. More than half the representatives of private enterprises and three-fourths of those in the public sector foresaw continued agricultural development. More than half of those interviewed said that their enterprises would need more agronomists in the future. Among the skills employers considered most necessary were comprehension and analysis of written information, writing proficiency, and leadership skills. Among the qualities considered most desirable were efficient use of time, desire for self improvement and loyalty to the enterprise or agency. It is recommended that educational institutions which train agronomists revise their curricula in order to strengthen those skills and qualities in their students.Se entrevistaron 94 patronos de profesionales de las Ciencias Agrícolas para auscultar sus puntos de vista sobre el futuro de las carreras agrícolas, los conocimientos y capacidades que desean en sus empleados profesionales y el grado en que los egresados tenían esos conocimientos y capacidades. Más de la mitad de los patronos de la empresa privada y tres cuartas partes de los del sector público confiaban que el desarrollo agrícola continuaría. Más de la mitad de los entrevistados opinaron que sus empresas tendrían mayor demanda de agrónomos en el futuro. Las destrezas que los entrevistados consideraban más necesarias eran la comprensión y la capacidad de analizar información escrita, la redacción correcta y técnica de liderato. Entre las cualidades que deseaban ver en sus empleados profesionales estaban la capacidad de planificar, de usar el tiempo eficazmente, tener el deseo de superarse y lealtad a la agencia o empresa. Se recomienda que las instituciones educativas que gradúan técnicos agrícolas revisen sus currículos para fortalecer estas destrezas y cualidades en sus estudiantes

Krylov’s Solver Based Technique for the Cascade Connection of Multiple N-Port Multimodal Scattering Matrices

In this paper a novel technique for cascading generalized scattering matrices based on a Krylov’s iterative solver is presented. This new technique is fully general, since it can be applied to solve the connection of an arbitrary number of networks, each one with an arbitrary number of ports, and it is easy to implement. This technique is able to compute, not only the modal spectra at the free ports of the global network, but also the modal spectra at the connected ports, so that the field inside the full network can be computed for an arbitrary incidence. In addition, this technique can also be used to evaluate the scattering parameters of the global network

Present day kynematic model of the Caribbean Plate in the boundary with the North American and Cocos plates

Este trabajo propone un modelo cinemático en la zona más occidental de la Placa Caribe, en los límites con la Placa Norteamericana y la Placa de Cocos. Para ello se ha realizado un análisis cluster de la sismicidad presente en la zona en función de: 1) su distribución espacial y 2) de la dirección de máximo acortamiento horizontal (ey), obtenidas del análisis de las construcciones de sus mecanismos focales mediante métodos de análisis poblacional de fallas. En total, se han considerado 57 de los 488 sismos con construcción del mecanismo focal situados en la zona. Los resultados obtenidos, tanto de los tensores, como de las trayectorias de deformación sugieren un modelo caracterizado por la rotación de ey en los límites de esta placa con la Placa Norteamérica y en la zona del Arco Volcánico Centroamericano. Esta rotación es congruente con un movimiento lateral hacia el ESE del área más occidental de la Placa Caribe, produciendo una extensión asociada a este movimiento en la zona central del Bloque de Chortis. Este modelo corrobora la existencia de un bloque tectónico costero en la Placa Caribe independiente del Bloque de Chortis (Forearc Sliver).This work proposes a present day kinematic tectonic model for the western part of the Caribbean Plate in relationship at its boundary with the North American and Cocos plates. We have performed the following cluster analysis of the instrumental seismicity within the area: 1) the spatial distribution of focal mechanism solutions and 2) the orientation of the maximum horizontal shortening (ey). Both studies come from the analysis of focal mechanisms by using the fault population technique. From the original available 488 earthquakes with focal mechanism (HCMT online database), we have considered 57 of them according to several criteria. Our results show a clockwise rotation of the ey trajectory across the boundary between Caribbean and North American plates and the Central American Volcanic Arc. This rotation agrees with a lateral tectonic movement towards ESE of the Chortis Block (Caribbean Plate). Furthermore, this model corroborates the existence of a coastal tectonic block within the Caribbean Plate that it is independent from the Chortis Block.Depto. de Geodinámica, Estratigrafía y PaleontologíaFac. de Ciencias GeológicasTRUEMinisterio de Educación y Cienciapu

Atlas de la pteridoflora ibérica y balear

Tomando como base el Atlas Florae Europeae se ha realizado una revisión corológica de la pteridoflora ibérica y balear.En prennant comme base Atlas Florae Europeae nous avons réalisé una révision chorologique de la pteridoflore ibérique et balear