Metal spar/superhybrid shell composite fan blades

The use of superhybrid materials in the manufacture and testing of large fan blades is analyzed. The FOD resistance of large metal spar/superhybrid fan blades is investigated. The technical effort reported was comprised of: (1) preliminary blade design; (2) detailed analysis of two selected superhybrid blade designs; (3) manufacture of two process evaluation blades and destructive evaluation; and (4) manufacture and whirligig testing of six prototype superhybrid blades

Quiet Clean Short-haul Experimental Engine (QCSEE) under-the-wing engine composite fan blade design report

A total of 38 quiet clean short haul experimental engine under the wing composite fan blades were manufactured for various component tests, process and tooling, checkout, and use in the QCSEE UTW engine. The component tests included frequency characterization, strain distribution, bench fatigue, platform static load, whirligig high cycle fatigue, whirligig low cycle fatigue, whirligig strain distribution, and whirligig over-speed. All tests were successfully completed. All blades planned for use in the engine were subjected to and passed a whirligig proof spin test

Impact resistance of current design composite fan blades tested under short-haul operating conditions

Boron/epoxy and graphite/epoxy composite blades were impacted in a rotating whirligig facility with conditions closely simulating those which might be experienced by a STOL engine impacted with various foreign objects. The tip speed of the rotating blades was 800 feet per second. The blades were impacted with simulated birds, real birds, ice balls, and gravel. The results of composite blade impact tests were compared with a titanium blade tested under similar conditions. Neither composite material indicated a clear superiority over the other. Blades made from both composite materials showed more damage than the titanium blades

Design of impact-resistant boron/aluminum large fan blade

The technical program was comprised of two technical tasks. Task 1 encompassed the preliminary boron/aluminum fan blade design effort. Two preliminary designs were evolved. An initial design consisted of 32 blades per stage and was based on material properties extracted from manufactured blades. A final design of 36 blades per stage was based on rule-of-mixture material properties. In Task 2, the selected preliminary blade design was refined via more sophisticated analytical tools. Detailed finite element stress analysis and aero performance analysis were carried out to determine blade material frequencies and directional stresses

Impact absorbing blade mounts for variable pitch blades

A variable pitch blade and blade mount are reported that are suitable for propellers, fans and the like and which have improved impact resistance. Composite fan blades and blade mounting arrangements permit the blades to pivot relative to a turbine hub about an axis generally parallel to the centerline of the engine upon impact of a large foreign object, such as a bird. Centrifugal force recovery becomes the principal energy absorbing mechanism and a blade having improved impact strength is obtained

Program for impact testing of spar-shell fan blades, test report

Six filament-wound, composite spar-shell fan blades were impact tested in a whirligig relative to foreign object damage resulting from ingestion of birds into the fan blades of a QCSEE-type engine. Four of the blades were tested by injecting a simulated two pound bird into the path of the rotating blade and two were tested by injecting a starling into the path of the blade

Poblamiento, movilidad y territorios entre las sociedades cazadoras-recolectoras de Patagonia

La transición Pleistoceno/Holoceno fue un tiempo crítico ambiental en el cual se produjo la dispersión humana del último continente en ser poblado, América del Sur. Los primeros colonos, que buscaban lugares para establecerse, fueron desafiados en América por la enorme variabilidad ambiental y los profundos y repentinos cambios climáticos de los momentos de la transición. Este artículo trata de ese proceso de poblamiento en la Patagonia, donde las ocupaciones humanas más antiguas están datadas entre 13.5 y 10.5 ka AP en tres diferentes focos geográficos: (a) las cuencas andinas de la vertiente Pacífica; (b) la cuenca del Macizo del Deseado; y (c) la cuenca magallánico-fueguina. Siguiendo los datos arqueológicos y paleoambientales (polen, faunas, sedimentos) y los fechados radiocarbónicos se proponen hipótesis sobre las formas de la colonización y la movilidad humana durante el final de la última gran glaciación y el Holoceno medio. El ingreso de los primeros grupos de cazadores-recolectores podría haber ocurrido por dos rutas diferentes, el borde Pacífico y la vertiente Atlántica. Desde ambos litorales y remontando los ríos hacia el interior del territorio los grupos habrían alcanzado en forma diferida ambos flancos cordilleranos. La alta movilidad de los primeros grupos humanos habría sido la clave para enfrentar el desafío de la colonización en esas altas latitudes.La transición Pleistoceno/Holoceno fue un tiempo crítico ambiental en el cual se produjo la dispersión humana del último continente en ser poblado, América del Sur. Los primeros colonos, que buscaban lugares para establecerse, fueron desafiados en América por la enorme variabilidad ambiental y los profundos y repentinos cambios climáticos de los momentos de la transición. Este artículo trata de ese proceso de poblamiento en la Patagonia, donde las ocupaciones humanas más antiguas están datadas entre 13.5 y 10.5 ka AP en tres diferentes focos geográficos: (a) las cuencas andinas de la vertiente Pacífica; (b) la cuenca del Macizo del Deseado; y (c) la cuenca magallánico-fueguina. Siguiendo los datos arqueológicos y paleoambientales (polen, faunas, sedimentos) y los fechados radiocarbónicos se proponen hipótesis sobre las formas de la colonización y la movilidad humana durante el final de la última gran glaciación y el Holoceno medio. El ingreso de los primeros grupos de cazadores-recolectores podría haber ocurrido por dos rutas diferentes, el borde Pacífico y la vertiente Atlántica. Desde ambos litorales y remontando los ríos hacia el interior del territorio los grupos habrían alcanzado en forma diferida ambos flancos cordilleranos. La alta movilidad de los primeros grupos humanos habría sido la clave para enfrentar el desafío de la colonización en esas altas latitudes

Changing ideas about others' intentions: updating prior expectations tunes activity in the human motor system

Predicting intentions from observing another agent’s behaviours is often thought to depend on motor resonance – i.e., the motor system’s response to a perceived movement by the activation of its stored motor counterpart, but observers might also rely on prior expectations, especially when actions take place in perceptually uncertain situations. Here we assessed motor resonance during an action prediction task using transcranial magnetic stimulation to probe corticospinal excitability (CSE) and report that experimentally-induced updates in observers’ prior expectations modulate CSE when predictions are made under situations of perceptual uncertainty. We show that prior expectations are updated on the basis of both biomechanical and probabilistic prior information and that the magnitude of the CSE modulation observed across participants is explained by the magnitude of change in their prior expectations. These findings provide the first evidence that when observers predict others’ intentions, motor resonance mechanisms adapt to changes in their prior expectations. We propose that this adaptive adjustment might reflect a regulatory control mechanism that shares some similarities with that observed during action selection. Such a mechanism could help arbitrate the competition between biomechanical and probabilistic prior information when appropriate for prediction

The Agent is Right: When Motor Embodied Cognition is Space-Dependent

The role of embodied mechanisms in processing sentences endowed with a first person perspective is now widely accepted. However, whether embodied sentence processing within a third person perspective would also have motor behavioral significance remains unknown. Here, we developed a novel version of the Action-sentence Compatibility Effect (ACE) in which participants were asked to perform a movement compatible or not with the direction embedded in a sentence having a first person (Experiment 1: You gave a pizza to Louis) or third person perspective (Experiment 2: Lea gave a pizza to Louis). Results indicate that shifting perspective from first to third person was sufficient to prevent motor embodied mechanisms, abolishing the ACE. Critically, ACE was restored in Experiment 3 by adding a virtual “body” that allowed participants to know “where” to put themselves in space when taking the third person perspective, thus demonstrating that motor embodied processes are space-dependent. A fourth, control experiment, by dissociating motor response from the transfer verb's direction, supported the conclusion that perspective-taking may induce significant ACE only when coupled with the adequate sentence-response mapping

A presença feminina na formação de docentes para o ensino superior: o perfil formativo de um curso de pós-graduação em Educação para a Ciência

A docência no Ensino Superior tem sido foco de interesse de pesquisadores da área de Ensino e Educação. Este artigo discute o perfil feminino em um curso de Pós-Graduação em Educação para Ciência e a empregabilidade deste público no ensino superior, analisando os dados à luz de outras pesquisas na área. Para tanto foi feito um levantamento em quatro revistas da área, com o intuito de identificar discussões relativas a essa temática. Usando descritores com foco na docência no ensino superior, 39 foram os trabalhos localizados e, após uma leitura mais aprofundada, apenas seis deles atendiam aos critérios estabelecidos. A seguir, foi feito um recorte nos dados apresentados em uma pesquisa realizada por Audi (2018), visando identificar qual o perfil profissional das mulheres formadas pelo Programa de Pós-Graduação em Educação para Ciências, da Unesp-Bauru/SP, de 1997 a 2016, além de um levantamentos junto à Plataforma Lattes buscando saber onde estas mulheres trabalham hoje. Durante o período analisado foram formados 524 novos pesquisadores, sendo 357 no mestrado (224 mulheres) e 167 no doutorado (52 mulheres). Os dados obtidos apontam que 88,58% delas atuam na área educacional, sendo que 75% das egressas trabalham em instituições de ensino superior públicas, como docentes/pesquisadoras. Conclui-se, entre outros pontos, que o programa analisado propicia uma formação de qualidade e que isso possibilita a inserção dos formandos no mercado de trabalho. Também apontamos que o quadro de docentes do programa (40) é composto por 21 mulheres (52,5%) de mulheres, sendo que oito delas (38,09%) foram formadas no próprio programa