During rescue operations of stranded vessels, it is essential to make immediate and reliable decisions to optimize the successful salvage potential and minimize risks of environmental damages and cost impacts. Pursuant to this scenario, the need arises for a numerical tool, which can more accurately forecast the stability conditions experienced by a vessel after running aground and help in the refloating operations of the unit. This study seeks to develop an adequate calculus systematization, which provides analytical capabilities for operational situations in case of stranding, thereby, supporting the decision-making process in these risk situations. Durante operaciones de rescate de embarcaciones varadas, es esencial tomar decisiones inmediatas y confiables para optimizar el potencial de salvamento exitoso y minimizar el riesgo de daños ambientales e impacto de costos. De acuerdo con este escenario, surge la necesidad para una herramienta numérica, que pueda predecir de manera más precisa las condiciones de estabilidad que esté experimentando la embarcación luego de encallar y ayudar en las operaciones de reflotación de la unidad. Este estudio busca desarrollar una adecuada sistematización de cálculo, que brinde capacidades analíticas para situaciones operativas en caso de encallar, así, apoyar el proceso de toma de decisiones durante estas situaciones de riesgo. Abstract Resumen Estabilidad de embarcaciones con varamiento de punto único

Conventionally the stability analysis of machine tools is restricted to determining if a particular operation will become unstable. The transient behaviour is not examined in any further detail. However, under certain conditions larger transient vibrations occur even though the process may ultimately be stable. A method of prediction of transient behaviour is presented and applied to variable speed cutting on a lathe where such transients are significant.

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The metal removal rates attainable during grinding may often be limited by the onset of an unstable tibration. commonly called regenerative chatter. Chatter is a self-induced vibration which leads to increased power consumption, a poor, generally unacceptable, workpiece surface finish, uneven wear of the grinding wheel and, in some cases, actual damage to the wheel.It is known that chatter is more likely to occur when the grinding wheel is hard and for this reason chatter often develops when grinding with diamond or cubic boron nitride (CBN) wheels, whose chief characteristic is that [hey are at Kungl Tekniska Hogskolan / Royal Institute of Technology on August 24, 2015

New York City Department of Environmental Protection and Metcalf & Eddy are researching effects of supplemental carbon on step-feed biological nutrient removal reactors with respects to improve total nitrogen removals. Based on historically low methanol kinetics (0.04 -0.08 mg N/mg VSS/d) as compared to literature cited methanol kinetic rates (0.08 -0.10 mg N/mg VSS/d) and rates observed with acetate (0.12 -0.25 mg N/mg VSS/d) and considering the significantly lower costs of methanol, further investigations into optimizing methanol for enhanced denitrification is warrented. Five feed configurations were studied including (B1 and D1 addition, D1 addition, C1, D1 addition, A6, C1, D1 addition and A6, C1, D1 addition at elevated influent TN loadings) to identify optimum feed locations to overcome anoxic volume limitations that may be causing the low kinetic rates. Addition of methanol to A6, C1 and D1 exhibited performance (at both the normal and elevated influent TN loadings) similar to that of B1 and D1 addition but at a lower Supplemental Carbon to Denitrified Nitrogen ratio (3.1:1 -4.3:1 normal N and 5.8:1 respectively). Additionally, the specific kinetic rates increased to levels similar to that of acetate. The increase in kinetics occurred when methanol was added to a zone in the pilot that had little to no wastewater carbon, thereby implying that there may be a specific anoxic methanol degrading bacteria that may face competition from other heterotrophic denitrifiers when methanol is fed in anoxic zone containing other carbon types. Thus, kinetic limitations caused by limited anoxic volumes can be lessened as seen by comparison of kinetics and performance of the various feed patterns; however, further optimization requires the separation of the effects methanol and wastewater carbon have on denitrification. This requires which the use of an ASM model fitted with equations that describe the processes related to methanol. Such a model will be employed in the next phase of optimization along with continued pilot testing including a GC-based method to deliver pilot methanol profiles.