714 resultados para Drainage engineering
Edinburgh Engineering Virtual Library (EEVL): The UK Gateway to Engineering Information on the Inter
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:
The main inputs, outputs and transfers of potassium (K) in soils and swards under typical south west England conditions were determined during 1999/00 and 2000/01 to establish soil and field gate K budgets under different fertilizer nitrogen (N) (0 and 280 kg ha(-1) yr(-1)) and drainage (undrained and drained) treatments. Plots receiving fertilizer N also received farmyard manure (FYM). Potassium soil budgets ranged, on average for the two years, from -5 (+N, drained) to +9 (no N and undrained) kg K ha(-1) yr(-1) and field gate budgets from +23 (+N, drained) to +89 (+N, undrained). The main inputs and outputs to the soil K budgets were fertilizer application (65%) and plant uptake (93%). Animals had a minor effect on K export but a major impact on K recycling. Nitrogen fertilizer application and drainage increased K uptake by the grass and, with it, the efficiency of K used. It also depleted easily available soil K, which could be associated with smaller K losses by leaching.
Resumo:
The Rio Tinto river in SW Spain is a classic example of acid mine drainage and the focus of an increasing amount of research including environmental geochemistry, extremophile microbiology and Mars-analogue studies. Its 5000-year mining legacy has resulted in a wide range of point inputs including spoil heaps and tunnels draining underground workings. The variety of inputs and importance of the river as a research site make it an ideal location for investigating sulphide oxidation mechanisms at the field scale. Mass balance calculations showed that pyrite oxidation accounts for over 93% of the dissolved sulphate derived from sulphide oxidation in the Rio Tinto point inputs. Oxygen isotopes in water and sulphate were analysed from a variety of drainage sources and displayed delta O-18((SO4-H2O)) values from 3.9 to 13.6 parts per thousand, indicating that different oxidation pathways occurred at different sites within the catchment. The most commonly used approach to interpreting field oxygen isotope data applies water and oxygen fractionation factors derived from laboratory experiments. We demonstrate that this approach cannot explain high delta O-18((SO4-H2O)) values in a manner that is consistent with recent models of pyrite and sulphoxyanion oxidation. In the Rio Tinto, high delta O-18((SO4-H2O)) values (11.2-13.6 parts per thousand) occur in concentrated (Fe = 172-829 mM), low pH (0.88-1.4), ferrous iron (68-91% of total Fe) waters and are most simply explained by a mechanism involving a dissolved sulphite intermediate, sulphite-water oxygen equilibrium exchange and finally sulphite oxidation to sulphate with O-2. In contrast, drainage from large waste blocks of acid volcanic tuff with pyritiferous veins also had low pH (1.7). but had a low delta O-18((SO4-H2O)) value of 4.0 parts per thousand and high concentrations of ferric iron (Fe(III) = 185 mM, total Fe = 186 mM), suggesting a pathway where ferric iron is the primary oxidant, water is the primary source of oxygen in the sulphate and where sulphate is released directly from the pyrite surface. However, problems remain with the sulphite-water oxygen exchange model and recommendations are therefore made for future experiments to refine our understanding of oxygen isotopes in pyrite oxidation. (C) 2009 Elsevier B.V. All rights reserved.