10,775 research outputs found
Flutter suppression by active control and its benefits
A general discussion of the airplane applications of active flutter suppression systems is presented with focus on supersonic cruise aircraft configurations. Topics addressed include a brief historical review; benefits, risks, and concerns; methods of application; and applicable configurations. Results are presented where the direct operating costs and performance benefits of an arrow wing supersonic cruise vehicle equipped with an active flutter suppression system are compared with corresponding costs and performance of the same baseline airplane where the flutter deficiency was corrected by passive methods (increases in structural stiffness). The design, synthesis, and conceptual mechanization of the active flutter suppression system are discussed. The results show that a substantial weight savings can be accomplished by using the active system. For the same payload and range, airplane direct operating costs are reduced by using the active system. The results also indicate that the weight savings translates into increased range or payload
Nitrogênio em sistemas pastoris.
Neste trabalho procedeu-se uma revisão na qual se abordou aspectos relacionados a ciclagem, fisiologia, metabolismo, nutrição de ruminantes, eficiência de uso e efeito sobre o meio ambiente deste nutriente, com intuito de disponibilizar informações para uso sustentável deste insumo em sistema pastoris.bitstream/item/45911/1/doc138-nitrogenio-em-sistemaspastoris.pd
Avaliação agronômica de forrageiras.
O desenvolvimento de tecnologias em pastagens requer constantemente pesquisas no sentido de se obter diferentes níveis de conhecimento do comportamento e respostas de forrageiras (gramíneas e leguminosas) a fatores ambientais (abióticos e bióticos), de utilização e manejo. Para tanto, os pesquisadores dispõem de diversos métodos, meios e técnicas, adequados a diferentes circunstâncias e objetivos de pesquisa. Dentre estas alternativas, estão as 'provas agronômicas', ou seja, aquelas cujas principais informações são obtidas mediante cortes e/ou estimativas da vegetação ou em parte desta, com ou sem a introdução do efeito animal. Estas provas geralmente são de baixo custo e de fácil implantação, por isto são bastante difundidas. Muito embora a interpretação e aplicabilidade de seus resultados ensejam algumas restrições, o que nem sempre é observado, e assim passam a gerar mais confusão do que conhecimento. Nesta revisão são definidos os diferentes tipos, as possíveis aplicações e limitações, de provas agronômicas em programa de avaliação de forrageiras.bitstream/item/70960/1/doc147-forrageiras-1.pd
Diabetes in Malta : current findings and future trends
Diabetes is a considerable global problem. Recent projections suggest that at least 194 million people suffer from diabetes worldwide. The World Health Organization suggests this number will increase to 333 million by 2025. Approximately four million deaths each year are caused by diabetes-related complications totaling an astounding 9% of deaths worldwide. Currently, epidemiological studies indicate that 1% of the Maltese population suffer from Type I Diabetes Mellitus and 9% from Type II Diabetes Mellitus. Following global predictions, it is probable that the incidence of Type I diabetes will increase also. This article evaluates the current Maltese diabetic care system and conducts a strategic analysis of diabetic practices. Recommendations for a cost-effective standard of care, legislative support for comprehensive diabetic care, and a national policy are proposed.peer-reviewe
Influence of correlated visual cues on auditory signal detection
Influence of correlated visual cues on auditory signal detectio
A note on the dyonic D6-brane
We study the dyon electric charge of D6-branes as eleven dimensional
KK-monopoles. We observe that the dyon charge is intimately related with the
existence of gauge connections and antisymmetric fields on the brane world
volume.Comment: 8 pages, Contribution to the 6th International Workshop on Conformal
Field Theory and Integrable Models, Landau Institute, Sept. 2002, to honour
A. Belavin on the occasion of his 60th birthda
Cosmology as Geodesic Motion
For gravity coupled to N scalar fields with arbitrary potential V, it is
shown that all flat (homogeneous and isotropic) cosmologies correspond to
geodesics in an (N+1)-dimensional `augmented' target space of Lorentzian
signature (1,N), timelike if V>0, null if V=0 and spacelike if V<0.
Accelerating cosmologies correspond to timelike geodesics that lie within an
`acceleration subcone' of the `lightcone'. Non-flat (k=-1,+1) cosmologies are
shown to evolve as projections of geodesic motion in a space of dimension
(N+2), of signature (1,N+1) for k=-1 and signature (2,N) for k=+1. This
formalism is illustrated by cosmological solutions of models with an
exponential potential, which are comprehensively analysed; the late-time
behviour for other potentials of current interest is deduced by comparison.Comment: 26 pages, 2 figures, journal version with additional reference
Manejo de pastagem.
Este folder apresenta informações básicas sobre manejo de pastagem: o objetivo do manejo de pastagem; sistemas de pastejo; taxa de lotação; pressão do pastejo, capacidade de suportebitstream/CPAF-RO-2010/14520/1/folder-pastagem.pdfFolder
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