722 resultados para Engineering Thermodynamics
Resumo:
El presente documento analiza las características de liderazgo de los gerentes “baby boomers” de la empresa transnacional Global Engineering S.A., que tiene oficinas en España, Cuba, Venezuela y Ecuador. Esta investigación se realiza sobre la premisa que los Gerentes de las cuatro oficinas pertenecen a la generación de los baby boomers, por lo se presenta la hipótesis de que, al pertenecer a una misma generación las características de liderazgo son similares. Los objetivos de la presente investigación, fueron el identificar las características de liderazgo de los gerentes, analizarlas, verificar si son eficaces, identificar las oportunidades de mejora y presentar un plan de mejora para la organización. Al presente estudio se lo define como exploratorio, descriptivo y correlacional, se utiliza como herramienta principal para la investigación el MLQ 5X versión corta creado por Bass y Avolio y adaptado por Vega y Zabala, se lo aplica a las cuatro oficinas de la empresa tanto a los gerentes como a los seguidores. Para la comprobación de la hipótesis, se utilizó la prueba t de Student, para establecer valores máximos y mínimos de los promedios de las características de liderazgo, para de esa manera conocer si los Gerentes de cada oficina tienen las mismas características, también se promediaron los valores resultantes de cada estilo de liderazgo para conocer si son eficaces para la realidad de la organización. Como herramienta para la mejora de toma de decisiones estratégica, se presenta el Cuadro de Mando integral, se establecen los objetivos principales para las perspectivas y se señalan los pasos de cómo debe ser el proceso de implementación del plan de coaching gerencial para la organización. De la investigación realizada se concluye que las características de liderazgo de los gerentes de la organización no se relacionan directamente con la generación a la que pertenecen, sino, dependen más del entorno, la situación y de los seguidores. Se recomienda la implementación del Cuadro de Mando Integral para mejorar la toma de decisiones estratégicas, haciendo énfasis en la propuesta de valor de implementar un plan de coaching gerencial para los gerentes de las distintas oficinas para así mejorar la eficacia de la organización.
Resumo:
In this paper, the available potential energy (APE) framework of Winters et al. (J. Fluid Mech., vol. 289, 1995, p. 115) is extended to the fully compressible Navier– Stokes equations, with the aims of clarifying (i) the nature of the energy conversions taking place in turbulent thermally stratified fluids; and (ii) the role of surface buoyancy fluxes in the Munk & Wunsch (Deep-Sea Res., vol. 45, 1998, p. 1977) constraint on the mechanical energy sources of stirring required to maintain diapycnal mixing in the oceans. The new framework reveals that the observed turbulent rate of increase in the background gravitational potential energy GPEr , commonly thought to occur at the expense of the diffusively dissipated APE, actually occurs at the expense of internal energy, as in the laminar case. The APE dissipated by molecular diffusion, on the other hand, is found to be converted into internal energy (IE), similar to the viscously dissipated kinetic energy KE. Turbulent stirring, therefore, does not introduce a new APE/GPEr mechanical-to-mechanical energy conversion, but simply enhances the existing IE/GPEr conversion rate, in addition to enhancing the viscous dissipation and the entropy production rates. This, in turn, implies that molecular diffusion contributes to the dissipation of the available mechanical energy ME =APE +KE, along with viscous dissipation. This result has important implications for the interpretation of the concepts of mixing efficiency γmixing and flux Richardson number Rf , for which new physically based definitions are proposed and contrasted with previous definitions. The new framework allows for a more rigorous and general re-derivation from the first principles of Munk & Wunsch (1998, hereafter MW98)’s constraint, also valid for a non-Boussinesq ocean: G(KE) ≈ 1 − ξ Rf ξ Rf Wr, forcing = 1 + (1 − ξ )γmixing ξ γmixing Wr, forcing , where G(KE) is the work rate done by the mechanical forcing, Wr, forcing is the rate of loss of GPEr due to high-latitude cooling and ξ is a nonlinearity parameter such that ξ =1 for a linear equation of state (as considered by MW98), but ξ <1 otherwise. The most important result is that G(APE), the work rate done by the surface buoyancy fluxes, must be numerically as large as Wr, forcing and, therefore, as important as the mechanical forcing in stirring and driving the oceans. As a consequence, the overall mixing efficiency of the oceans is likely to be larger than the value γmixing =0.2 presently used, thereby possibly eliminating the apparent shortfall in mechanical stirring energy that results from using γmixing =0.2 in the above formula.
Resumo:
This paper describes a technique that can be used as part of a simple and practical agile method for requirements engineering. The technique can be used together with Agile Programming to develop software in internet time. We illustrate the technique and introduce lazy refinement, responsibility composition and context sketching. Goal sketching has been used in a number of real-world development projects, one of which is described here.
Resumo:
The new dioxatetraazamacrocycle (L-1) was synthesized by a 2 + 2 condensation and characterized. Stability constants of its copper(II) complexes were determined by spectrophotometry in DMSO at 298.2 K in 0. 10 mol dm(-3) KClO4. Mainly dinuclear complexes are formed and the presence of mononuclear species is dependent on the counterion (Cl- or ClO4-). The association constants of the dinuclear copper(II) complexes with dicarboxylate anions [oxalate (oxa(2-)), malonate (mal(2-)), succinate (suc(2-)), and glutarate (glu(2-))] were also determined by spectrophotometry at 298.2 K in DMSO, and it was found that values decrease with an increase of the alkyl chain between the carboxylate groups. X-Band EPR spectra of the dicopper(II) complexes and of their cascade species in frozen DMSO exhibit dipole-dipole coupling, and their simulation, together with their UV-vis spectra, showed that the copper centres of the complexes in solution had square pyramidal geometries though with different distortions. From the experimental data, it was also possible to predict the Cu...Cu distances, the minimum being found at 6.4 angstrom for the (Cu2LCl4)-Cl-1 complex and then successively this distance slightly increases when the chloride anions are replaced by dicarboxylate anions, from 6.6 angstrom for oxa(2-) to 7.8 for glu(2-). The crystal structures of the dinuclear copper cascade species with oxa(2-) and suc(2-) were determined and showed one anion bridging both copper centres and Cu...Cu distances of 5.485(7) angstrom and 6.442(8) angstrom, respectively.