9,542 research outputs found

    Flight evaluation of a pneumatic system for unsteady pressure measurements using conventional sensors

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    A flight experiment was conducted to evaluate a pressure measurement system which uses pneumatic tubing and remotely located electronically scanned pressure transducer modules for in-flight unsteady aerodynamic studies. A parametric study of tubing length and diameter on the attenuation and lag of the measured signals was conducted. The hardware was found to operate satisfactorily at rates of up to 500 samples/sec per port in flight. The signal attenuation and lag due to tubing were shown to increase with tubing length, decrease with tubing diameter, and increase with altitude over the ranges tested. Measurable signal levels were obtained for even the longest tubing length tested, 4 ft, at frequencies up to 100 Hz. This instrumentation system approach provides a practical means of conducting detailed unsteady pressure surveys in flight

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    Topographic Map of the Bedrock Surface, Aurora North Quadrangle, Kane and Du Page Counties, Illinois

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    Computer generated mapIncludes 1 ancillary map, 1 3-D model, 1 table, text, col. ill., index to adjoining 7.5-minute quadrangles, and location mapIncludes bibliographical reference

    A Rhetorical Analysis of Edward Albee\u27s Tiny Alice

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    A difference of opinion exists today among the many branches of knowledge as to what constitutes the proper study of mankind. Since it is not always expedient nor desirable to subject living persons to laboratory experiments, models have been devised to study man. For many years lower forms of life have been studied and the resulting data applied by means of analogy to the behavior of man. More recently, man has been compared to the various input-output systems of machines. However, to be applicable to human behavior such models or analogies must account for the fact that human beings create and use symbolic communication systems which are called languages. The significance of this study lies in the observation that man is a social animal, differing from other animals in his ability to create and use language. Thus a proper study of mankind must give consideration to man\u27s use of language in relation to his cultural and social environment. The most effective method yet devised by man for social control has been his persuasive use of language. Throughout recorded history man has used persuasive-language arts in discussion, debate, drama, and in religious ritual to convince his fellow man to follow his leadership. These modes of persuasion are the foundation for a rhetorical study. Since the end of persuasion is said to be action, and persuasion through art is one of man\u27s most useful tools for change, the statement of the American dramatist Edward Albee concerning his purpose in writing becomes germane: ...when I write a play, I\u27m interested in changing the way people look at themselves and the way they look at life. Since Albee\u27s stated purpose is change, his discourse should be persuasive. Whether or not this is true is, as yet, one of the unanswered questions that this study has proposed for answer

    Determination and impact of surface radiative processes for TOGA COARE

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    Experiments using atmospheric general circulation models have shown that the atmospheric circulation is very sensitive to small changes in sea surface temperature in the tropical western Pacific Ocean warm pool region. The mutual sensitivity of the ocean and the atmosphere in the warm pool region places stringent requirements on models of the coupled ocean atmosphere system. At present, the situation is such that diagnostic studies using available data sets have been unable to balance the surface energy budget in the warm pool region to better than 50 to 80 W/sq m. The Tropical Ocean Global Atmosphere (TOGA) Coupled Ocean Atmosphere Response Experiment (COARE) is an observation and modelling program that aims specifically at the elucidation of the physical process which determine the mean and transient state of the warm pool region and the manner in which the warm pool interacts with the global ocean and atmosphere. This project focuses on one very important aspect of the ocean atmosphere interface component of TOGA COARE, namely the temporal and spatial variability of surface radiative fluxes in the warm pool region

    Garlic as an Alternative Anthelmintic in Sheep

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    An increase in the anthelmintic resistance of parasites in small ruminants and a push towards non-chemical farming has led researchers to search for alternative forms of anthelmintics. The efficacy of treating sheep by using natural garlic extract with respect to changes in weight, fecal egg counts (FEC), and packed cell volume (PCV) was investigated. Sheep were treated every 4 weeks for 8 weeks with saline (control) Ivermectin, or natural garlic extract and samples were collected weekly to determine FEC and PCV. Sheep were weighed at the time of sample collection to determine weight change. There were no significant differences between the Ivermectin and natural garlic extract treated sheep with respect to weight changes, FEC or PCV. The Ivermectin and natural garlic extract treated sheep had significantly greater (P \u3c 0.05) weight changes and PCV compared to the control. The control sheep had a significantly higher (P \u3c 0.05) FEC compared to the Ivermectin and natural garlic extract treated sheep. Administering natural garlic extract as anthelmintic is a variable alternative to Ivermectin

    The Mg/Ca–temperature relationship in brachiopod shells: calibrating a potential palaeoseasonality proxy

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    Brachiopods are long-lived, long-ranging, extant organisms, of which some groups precipitate a relatively diagenetically stable low magnesium calcite shell. Previous work has suggested that the incorporation of Mg into brachiopod calcite may be controlled by temperature (Brand et al., 2013). Here we build upon this work by using laser ablation sampling to define the intra-shell variations in two modern brachiopod species,Terebratulina retusa (Linnaeus, 1758) and Liothyrella neozelanica (Thomson, 1918). We studied three T. retusa shells collected live from the Firth of Lorne, Scotland, which witnessed annual temperature variations on the order of 7 °C, in addition to four L. neozelanica shells, which were dredged from a water depth transect (168–1488 m) off the north coast of New Zealand. The comparison of intra-shell Mg/Ca profiles with shell δ<sup>18</sup>O confirms a temperature control on brachiopod Mg/Ca and supports the use of brachiopod Mg/Ca as a palaeoseasonality indicator. Our preliminary temperature calibrations are Mg/Ca = 1.76 ± 0.27 e<sup>(0.16 ± 0.03)T</sup>, R<sup>2</sup> = 0.75, for T. retusa and Mg/Ca = 0.49 ± 1.27 e<sup>(0.2 ± 0.11)T</sup>, R<sup>2</sup> = 0.32, for L. neozelanica (errors are 95% confidence intervals)

    Experimental characterization of the effects of pneumatic tubing on unsteady pressure measurements

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    Advances in aircraft control system designs have, with increasing frequency, required that air data be used as flight control feedback. This condition requires that these data be measured with accuracy and high fidelity. Most air data information is provided by pneumatic pressure measuring sensors. Typically unsteady pressure data provided by pneumatic sensing systems are distorted at high frequencies. The distortion is a result of the pressure being transmitted to the pressure sensor through a length of connective tubing. The pressure is distorted by frictional damping and wave reflection. As a result, air data provided all-flush, pneumatically sensed air data systems may not meet the frequency response requirements necessary for flight control augmentation. Both lab and flight test were performed at NASA-Ames to investigate the effects of this high frequency distortion in remotely located pressure measurement systems. Good qualitative agreement between lab and flight data are demonstrated. Results from these tests are used to describe the effects of pneumatic distortion in terms of a simple parametric model
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