47 research outputs found

    High Efficiency Megawatt Motor Preliminary Design

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    The High Efficiency Megawatt Motor (HEMM) is being designed to meet the needs of Electrified Aircraft Propulsion (EAP). A preliminary design has been completed and risk reduction activities are being conducted in three key areas: cryogenic cooler design, superconducting rotor coil design and manufacturing, and stator thermal management. The key objective of HEMM is to establish a motor technology which simultaneously attains high specific power (>16kW/kg ratio to electromagnetic weight) and high efficiency (>98%) by judicious application of high temperature superconducting wire and integrated thermal management. Another important feature is to achieve the performance goals with an eye to aircraft integration constraints. An electromagnetic analysis was performed which shows that the proposed HEMM design meets the performance objectives if key current capability and mechanical constraints are achieved. The risk reduction activities are the first assessment of the key design features. The HEMM technology could be applied to a range of aircraft types that require megawatt level electrical power

    The Anatomy of Memory Politics: A Formalist Analysis of Tate Britain’s ‘Artist and Empire’ and the Struggle over Britain’s Imperial Past

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    In this paper, I propose a new approach for understanding the meaning of memory politics, which draws upon the archetypal literary criticism of Northrop Frye. I suggest that the four archetypes elaborated by Frye—comedy, romance, tragedy, and satire—can be used as a heuristic device for interpreting the contested historical narratives that are associated with the politics of memory. I illustrate this approach through a case-study of Artists and Empire: Facing Britain’s Imperial Past, an exhibition held at Tate Britain in 2016, amidst increasing contestation over the meaning of the British Empire. In sum, I find that the exhibit narrated Britain’s imperial past as a comedy, in which a key theme was the progressive cultural mixing of the British and the people they colonized. To conclude, I discuss the implications of such a narrative for constructing an inclusive, postcolonial British identity. As an alternative, I draw on Aristotle to suggest that a tragic narrative would have been more propitious

    Analysis of Dehydration and Strength in Elite Badminton Players

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    Background: The negative effects of dehydration on aerobic activities are well established. However, it is unknown how dehydration affects intermittent sports performance. The purpose of this study was to identify the level of dehydration in elite badminton players and its relation to muscle strength and power production. Methodology: Seventy matches from the National Spanish badminton championship were analyzed (46 men?s singles and 24 women?s singles). Before and after each match, jump height and power production were determined during a countermovement jump on a force platform. Participants? body weight and a urine sample were also obtained before and after each match. The amount of liquid that the players drank during the match was also calculated by weighing their individual drinking bottles. Results and Discussion: Sweat rate during the game was 1.1460.46 l/h in men and 1.0260.64 l/h in women. The players rehydrated at a rate of 1.1060.55 l/h and 1.0160.44 l/h in the male and female groups respectively. Thus, the dehydration attained during the game was only 0.3760.50% in men and 0.3260.83% in women. No differences were found in any of the parameters analyzed during the vertical jump (men: from 31.8265.29 to 32.9064.49 W/kg; p.0.05, women: from 26.3664.73 to 27.2564.44 W/kg; p.0.05). Post-exercise urine samples revealed proteinuria (60.9% of cases in men and 66.7% in women), leukocyturia (men = 43.5% and women = 50.0%) and erythrocyturia (men = 50.0% and women = 21.7%). Conclusions: Despite a moderate sweat rate, badminton players adequately hydrated during a game and thus the dehydration attained was low. The badminton match did not cause muscle fatigue but it significantly increased the prevalence of proteinuria, leukocyturia and erythrocyturia

    The Need of Other Elements

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    A number of natural drinks and ingredients used in hydration beverages have been discussed, focusing on their effectiveness for post-exercise rehydration. Because of excess diuresis, complete, rapid, and sustained restoration of fluid balance remains a challenge. The most effective ingredient to promote fluid retention is sodium, although the possible merits of milk protein, creatine, and additional potassium were presented. Cultural preferences may lead some individuals to rehydrate with Roselle infu-sion, mineral water, or coconut water; doing so has been shown not to deter from the goal of restoring body fluid. Skimmed milk has been shown to be more effective than conventional sports drinks and water and may be a good rehydration choice in the absence of lactose intolerance. Furthermore, sports drinks with added milk or whey protein, which may be desirable to provide amino acids and help recov-ery, have been shown not to impair rehydration. The use of caffeinated beverages, although favored by many consumers and shown not to impair chronic hydration, remains more of an open question for quick post-exercise rehydration. Evidence was provided to show why regular beer is contraindicated when effective post-exercise rehydration is desired, together with evidence about the serious limitations associ-ated with the use of glycerol.UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Sociales::Centro de Investigación en Ciencias del Movimiento Humano (CIMOHU
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