Modelo de plan estratégico para la gestión de inventarios para los repuestos John Deere de Ponce Yepes S.A.

En el presente trabajo se propone un modelo de plan estratégico, cuya aplicación se sugiere en la empresa Ponce Yepes S.A., con el objetivo de conseguir una eficiente y eficaz gestión de inventarios para la Línea de Repuestos John Deere. El estudio se ha dividido en tres capítulos, en los cuales se van estructurando progresivamente las diferentes etapas para el establecimiento del plan estratégico que se propone. El primer capítulo contiene un resumen teórico sobre la administración de inventarios, los conceptos, la clasificación y los modelos más difundidos. En el segundo capítulo se realiza el análisis de la situación actual de la empresa, enfocado a la Línea de Repuestos John Deere. Este capítulo incluye el análisis del entorno, el esquema de funcionamiento actual del sistema de inventarios, el análisis FODA, la determinación de los clientes internos y externos con sus correspondientes demandas, la elaboración y análisis de las matrices de evaluación de factores internos y externos, en forma individual y combinada; y, se presentan las listas de las estrategias a aplicarse. En el tercer capítulo se presenta la estructuración del plan estratégico, que está compuesto por la reformulación de la misión y visión, el establecimiento de objetivos globales para la gestión de repuestos John Deere, la formulación de las estrategias y políticas para alcanzar dichos objetivos y se concluye detallando el plan operativo, el cual incluye la matriz de aplicación del plan operativo, el cronograma de cumplimiento, el modelo de evaluación y seguimiento de dicho plan, y el flujo de caja del presupuesto de costos. Finalmente se presentan las conclusiones y recomendaciones resultantes del modelo de plan estratégico propuesto.

Dr John Snow and an early investigation of groundwater contamination

John Snow was a physician but his studies of the way in which cholera is spread have long attracted the interest of hydrogeologists. From his investigation into the epidemiology of the cholera outbreak around the well in Broad Street, London, in 1854, Snow gained valuable evidence that cholera is spread by contamination of drinking water. Subsequent research by others showed that the well was contaminated by sewage. The study therefore represents one of the first, if not the first, study of an incident of groundwater contamination in Britain. Although he had no formal geological training, it is clear that Snow had a much better understanding of groundwater than many modern medical practitioners. At the time of the outbreak Snow was continuing his practice as a physician and anaesthetist. His casebooks for 1854 do not even mention cholera. Yet, nearly 150 years later, he is as well known for his work on cholera as for his pioneering work on anaesthesia, and his discoveries are still the subject of controversy.

Nitrogen management is essential to prevent tropical oil palm plantations from causing ozone pollution

More than half the world's rainforest has been lost to agriculture since the Industrial Revolution. Among the most widespread tropical crops is oil palm (Elaeis guineensis): global production now exceeds 35 million tonnes per year. In Malaysia, for example, 13% of land area is now oil palm plantation, compared with 1% in 1974. There are enormous pressures to increase palm oil production for food, domestic products, and, especially, biofuels. Greater use of palm oil for biofuel production is predicated on the assumption that palm oil is an “environmentally friendly” fuel feedstock. Here we show, using measurements and models, that oil palm plantations in Malaysia directly emit more oxides of nitrogen and volatile organic compounds than rainforest. These compounds lead to the production of ground-level ozone (O3), an air pollutant that damages human health, plants, and materials, reduces crop productivity, and has effects on the Earth's climate. Our measurements show that, at present, O3 concentrations do not differ significantly over rainforest and adjacent oil palm plantation landscapes. However, our model calculations predict that if concentrations of oxides of nitrogen in Borneo are allowed to reach those currently seen over rural North America and Europe, ground-level O3 concentrations will reach 100 parts per billion (109) volume (ppbv) and exceed levels known to be harmful to human health. Our study provides an early warning of the urgent need to develop policies that manage nitrogen emissions if the detrimental effects of palm oil production on air quality and climate are to be avoided.

Electrochemical determination of plant-derived leuco-indigo after chemical reduction by glucose

Electrochemical determination of redox active dye species is demonstrated in indigo samples contaminated with high levels of organic and inorganic impurities. The use of a hydrodynamic electrode system based on a vibrating probe (250 Hz, 200 mu m lateral amplitude) allows time-independent diffusion controlled signals to be enhanced and reliable concentration data to be obtained under steady state conditions at relatively fast scan rates up to 4 V s-1In this work the indigo content of a complex plant-derived indigo sample (dye content typically 30%) is determined after indigo is reduced by addition of glucose in aqueous 0.2 M NaOH. The soluble leuco-indigo is measured by its oxidation response at a vibrating electrode. The vibrating electrode, which consisted of a laterally vibrating 500 mu m diameter gold disc, is calibrated with Fe(CN)(6) 3-/4- in 0.1 M KCl and employed for indigo determination at 55, 65, and 75 C in 0.2 M NaOH. Determinations of the indigo content of 25 different samples of plant-derived indigo are compared with those obtained by conventional spectrophotometry. This comparison suggests a significant improvement by the electrochemical method, which appears to be less sensitive to impurities.