The boundary element method (BEM) is implemented in the simulation of the filling of anisotropic fiber reinforced preforms used in the resin transfer molding process (RTM). They are analyzed both as a homogeneous and a non-homogeneous domain. In the former case, two injection regimes are considered: constant pressure and constant flow. The BEM results of flow front positions, pressure history and pressure profiles in the two main directions of permeability are compared to analytical and experimental results. In the second case of non-homogeneous domain, the domain integral appearing in the boundary integral formulation is treated by the dual reciprocity (DR) technique; the DR-BEM results of the curve pressure versus radial distance Pressure vs. Radial distance in the main directions of permeability are compared to numerical results obtained from the solution of the equation of pressure using MacLaurin series. In this case, the influence of the linear radial change of the fiber volume fraction on the flow front positions and on the curves of pressure versus radial distance is analyzed Pressure vs. Radial distance. For the homogeneous case, an acceptable coincidence between BEM and analytical results is appreciated as the circular inlet effect, which is considered in the BEM formulation and is not considered in the analytical method, lessens with the time. In nonhomogeneous case, the coincidence among the DR-BEM and the numerical MacLaurin series results indicates that the DR-BEM is a promising technique to deal with the infiltration phenomenon of anisotropic reinforced preforms in nonhomogeneous domains.

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comercio en la última década. Para ello se requiere analizar su capacidad de internacionalización en términos de recursos, habilidades y capacidades para desarrollar estrategias que permitan participar de la nueva dinámica en una forma apropiada. Se propone un sistema de inferencia difuso para modelar estos factores que determinan el éxito en un proceso de internacionalización. Se utilizan variables lingüísticas, extraídas de empresarios, expertos, consultores e investigadores de la materia y, por medio del juicio de expertos, se definen los factores internos que explican la capacidad de internacionalización. El modelo propuesto se aplica por medio de un estudio de caso del clúster textilconfección en Medellín (Colombia). Se obtiene en la ejecución del modelo un índice global particular de 26.7 para las capacidades internas para iniciar un proceso de internacionalización. El resultado obtenido confirma la hipótesis de que las capacidades y recursos de que dispone actualmente el sector analizado no son suficientes para una inserción exitosa en el mercado internacional y, lo más importante, especifica los factores y variables en los que intervenir para mejorar la capacidad interna de internacionalización. Derechos Reservados © 2015 Universidad Nacional Autónoma de México, Facultad de Contaduría y Administración. Este es un artículo de acceso abierto distribuido bajo los términos de la Licencia Creative Commons CC BY-NC-ND 4.0.

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Purpose This paper aims to study the influence of innovation on micro, small and medium-sized enterprises (MSME) performance in Colombia through the 403 MSMES survey analysis. In particular, this paper measures the effect of participation in R&D alliances, product innovation and process innovation on it. Design/methodology/approach MSME performance is measured through a composite index, estimated through principal components analysis using polychoric correlations, which is based on eight self-reported assessments of MSME performance. Then, this measure of performance is related to MSME participation in R&D alliances and the product and process development stance of the MSME based on an adaptation of the Miles and Snow business classification scheme, by means of an ANOVA and a linear regression. Findings Colombian SMEs are not significantly benefitted from participation on R&D alliances. Instead, their performance appears to be dependent upon their internal innovation efforts directed to product development. Moreover, the results suggest that imitators get a performance almost as high as innovators. Originality/value Innovation activities in Colombian SMEs are carried out informally, as they are mostly uninterested to engage in R&D activities and to develop new products by own initiative. Moreover, few of them have an R&D department. In regard to technology, results suggest that almost half of SMEs are classified as followers, namely, they use the same technology as competitors.