Comparison of Two Multidisciplinary Optimization Strategies for Launch-Vehicle Design

The investigation focuses on development of a rapid multidisciplinary analysis and optimization capability for launch-vehicle design. Two multidisciplinary optimization strategies in which the analyses are integrated in different manners are implemented and evaluated for solution of a single-stage-to-orbit launch-vehicle design problem. Weights and sizing, propulsion, and trajectory issues are directly addressed in each optimization process. Additionally, the need to maintain a consistent vehicle model across the disciplines is discussed. Both solution strategies were shown to obtain similar solutions from two different starting points. These solutions suggests that a dual-fuel, single-stage-to-orbit vehicle with a dry weight of approximately 1.927 x 10(exp 5)lb, gross liftoff weight of 2.165 x 10(exp 6)lb, and length of 181 ft is attainable. A comparison of the two approaches demonstrates that treatment or disciplinary coupling has a direct effect on optimization convergence and the required computational effort. In comparison with the first solution strategy, which is of the general form typically used within the launch vehicle design community at present, the second optimization approach is shown to he 3-4 times more computationally efficient

Silicofitólitos como indicadores de descontinuidades litológicas em três pedons da região de Búzios/Cabo Frio, RJ.

Foram identificados e quantificados silicofitólitos extraídos de amostras de horizontes de três pedons sob vegetação xeromórfica da região de Cabo Frio. Estes microfósseis, além bons indicadores para o estudo da evolução da vegetação durante o Quaternário, confirmaram a presença de horizontes A enterrados (Ab) e descontinuidades litológicas, identificados em exame morfológico no campo e posteriormente confirmados por análises físicas, químicas, orgânicas, isotópicas e micromorfológicas

Bringing together Brazilian soil scientists to share soil data.

Brazilian soil scientists have recently created a soil data repository using community-built standards and following open data policies in an attempt to address the issues mentioned above. The Free Brazilian Repository for Open Soil Data - febr -, accessible through www.ufsm.br/febr, is a centralized repository targeted at storing open soil data and serving it in a standardized and harmonized format, for various applications. This paper describes the features of febr and the opportunities that it creates for soil science.Na publicação: Wenceslau Teixeira