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Este artículo tiene por objetivo identificar los criterios de selección de proveedores de servicios logísticos, sus respectivos indicadores de desempeño y su alineación en los procesos de selección y evaluación de proveedores en el sector de comercio minorista. Se realizó un estudio de múltiples casos en un operador logístico y en cuatro consignatarios, por medio de entrevistas, informes de indicadores de desempeño y observaciones directas. Los resultados muestran que son pocos los criterios comunes; el “costo de flete” es usado por todas las empresas, y los criterios relacionados a la calidad de los servicios prestados no son muy gestionados. Además, existe poca alineación entre criterios e indicadores, lo que apunta a que las empresas no adoptan mecanismos de evaluación de los proveedores de servicios logísticos.

Computational methods for the calculation of dynamical properties of fluids might consider the system as a continuum or as an assembly of molecules. Molecular dynamics (MD) simulation includes molecular resolution, whereas computational fluid dynamics (CFD) considers the fluid as a continuum. This work provides a review of hybrid methods MD/CFD recently proposed in the literature. Theoretical foundations, basic approaches of computational methods, and dynamical properties typically calculated by MD and CFD are first presented in order to appreciate the similarities and differences between these two methods. Then, methods for coupling MD and CFD, and applications of hybrid simulations MD/CFD, are presented.

The role played by electron correlation and vibrational correction on the polarizability of the LiH molecule is demonstrated. We present results for the dipole moment, polarizability and first hyperpolarizability of the LiH molecule obtained through many-body perturbation-theory, coupled-cluster and quadratic configuration interaction methods. Our best result for the dipole polarizability, obtained using the QCISD(T) scheme, indicates that the vibrational contribution is appreciable, amounting to ca. 10% of the total polarizability. Regarding the first hyperpolarizability, the vibrational contribution is even more important and has opposite sign in comparison with the electronic contribution.