Absorption of broadband noise by sonic crystals consisting of microperforated cylindrical shells is proposed and experimentally demonstrated. The theoretical study has been performed in the framework of multiple scattering method, where a model for the T matrix of the microperforated shells has been developed. It has been predicted an extraordinary broadband sound absorption that is explained in terms of the multiple scattering phenomena occurring at the surfaces of the absorptive units—the microperforated panels. Our proposal has been supported by experiments performed on a structure consisting of 3 rows of cylindrical shells 3 meters height.

A systematic study of noise barriers based on sonic crystals made of cylinders that use recycled materials like absorbing component is reported here. The barriers consist of only three rows of perforated metal shells filled with rubber crumb. Measurements of reflectance and transmittance by these barriers are reported. Their attenuation properties result from a combination of sound absorption by the rubber crumb and reflection by the periodic distribution of scatterers. It is concluded that the porous cylinders can be used as building blocks whose physical parameters can be optimized in order to design efficient barriers adapted to different noisy environments.

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Cómo citar este artículo/Citation: Cruz-Ramírez, M.; Escalona-Reyes, M.; Cabrera-García, S.; Martínez-Cepena, M. C. (2014). Análisis cienciométrico de las publicaciones educacionales cubanas en la WoS y Scopus (2003)(2004)(2005)(2006)(2007)(2008)(2009)(2010)(2011)(2012) Resumen: Esta investigación consiste en un análisis cienciométrico de las publicaciones educacionales cubanas, referenciadas en la WoS y Scopus durante el período [2003][2004][2005][2006][2007][2008][2009][2010][2011][2012]. Mediante un procedimiento de normalización, las palabras clave se clasifican con base en las categorías generales del tesauro ERIC. La matriz de datos comprende un total de 286 observaciones con 42 variables (41 categorías generales del tesauro y el año de publicación). A partir de varios indicadores se realiza una caracterización del conjunto de publicaciones. La productividad diacrónica tiene tendencia al crecimiento, con irregularidades que son explicadas de forma hipotética. El análisis estadístico multivariado facilita la clasificación de las investigaciones reportadas, así como la identificación de patrones subyacentes que sirven para caracterizar las publicaciones afines de mayor visibilidad.Palabras clave: Cienciometría; publicaciones científicas; investigación educacional; Web of Science; Scopus; Cuba. Scientometric analysis of Cuban educational publications in WoS and Scopus (2003-2012)Abstract: This research consists of a statistical analysis of Cuban educational publications indexed in WoS and Scopus during the period [2003][2004][2005][2006][2007][2008][2009][2010][2011][2012]. By means of a normalization procedure, keywords are classified according to the general categories of the ERIC thesaurus. The resulting data matrix comprised a total of 286 observations with 42 variables (41 general categories from the thesaurus plus the year of publication). Using various indicators, a characterization of the set of publications is produced. Productivity over time shows a tendency for growth, with irregularities that are explained hypothetically. A multivariate statistical analysis enables the classification of the reported investigations, as well as the identification of underlying patterns which are useful for characterizing similar publications of a greater visibility.Keywords: Scientometrics; scientific publications; education research; Web of Science; Scopus; Cuba.Copyright: © 2014 CSIC. Este es un artículo de acceso abierto distribuido bajo los términos de la licencia Creative Commons Attribution-Non Commercial (by-nc) Spain 3.0.