2,700 research outputs found

    A citation history of measurements of Newtons constant of Gravity

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    We created and analyzed a citation history of papers covering measurements of Newtons constant of gravity from 1686 to 2016. Interest concerning the true value of the gravitational constant was most intense in the late 90s to early 2000s and is gaining traction again in the present. Another network consisting of the same papers was created using citations from databases to display the prominence of papers on Newtons constant in the wider scientific community. In general, papers that were important in one network remained important in the other while papers that had little importance in one network remained unimportant in the other. The US contributes the most to literature on the topic both in where journals were published and where the work was done; however, many other countries, such as China, Russia, France, Germany, Switzerland, and the UK also provide many papers on Newtons G. Work done within certain countries tends to be considered more important and cited more often within that country. Recent efforts promoting international collaboration may have an impact on this trend

    Turbulence modeling for sharp-fin-induced shock wave/turbulent boundary-layer interactions

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    Solutions of the Reynolds averaged Navier-Stokes equations are presented and compared with a family of experimental results for the 3-D interaction of a sharp fin induced shock wave with a turbulent boundary layer. Several algebraic and two equation eddy viscosity turbulence models are employed. The computed results are compared with experimental surface pressure, skin friction, and yaw angle data as well as the overall size of the interaction. Although the major feature of the flow fields are correctly predicted, several discrepancies are noted. Namely, the maximum skin friction values are significantly underpredicted for the strongest interaction cases. These and other deficiencies are discussed

    Documentation of Two- and Three-Dimensional Hypersonic Shock Wave/Turbulent Boundary Layer Interaction Flows

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    Experimental data for a series of two- and three-dimensional shock wave/turbulent boundary layer interaction flows at Mach 7 are presented. Test bodies, composed of simple geometric shapes, were designed to generate flows with varying degrees of pressure gradient, boundary-layer separation, and turning angle. The data include surface-pressure and heat-transfer distributions as well as limited mean-flow-field surveys in both the undisturbed and the interaction regimes. The data are presented in a convenient form for use in validating existing or future computational models of these generic hypersonic flows

    Intersecting Shock-Wave/Turbulent Boundary-Layer Interactions at Mach 8.3

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    Experimental data for two three-dimensional intersecting shock-wave/turbulent boundary-layer interaction flows at Mach 8.3 are presented. The test bodies, composed of two sharp fins fastened to a flat-plate test bed, were designed to generate flows with varying degrees of pressure gradient, boundary-layer separation, and turning angle. The data include surface pressure and heat transfer distributions as well as mean flow-field surveys both in the undisturbed and interaction regimes. The data are presented in a convenient form to be used to validate existing or future computational models of these hypersonic flows. The data are also on a 3.5-inch diskette included and are available through E-mail

    Flow routing in mangrove forests: field data obtained in Trang, Thailand

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    Mangroves grow in the intertidal parts of sheltered tropical coastlines, facilitating coastal stabilization and wave attenuation. Mangroves are widely threatened nowadays, although past studies have indicated their contribution to coastal safety. Most of these studies were based on numerical modeling however and a proper database with field observations is lacking yet. This paper presents part of the results of an extensive field campaign in a mangrove area in Trang Province, Thailand. The study area covers the outer border of an estuarine mangrove creek catchment. Data have been collected on elevation, vegetation, water levels, flow directions and flow velocities throughout this study area. Due to the tough conditions in the field, developing a suitable method for data collection and processing has been a major challenge in this study. Analysis of the hydrodynamic data uncovers the change of flow directions and velocities throughout a mangrove creek catchment over one tidal cycle. In the initial stages of flooding and the final stages of ebbing, creeks supply water to the lower elevated parts of the mangroves. In between these stages, the entire forest bordering the estuary is flooded and flow directions are perpendicular to the forest fringe. Flow velocities within the creeks are still substantially higher than those within the forest, as the creeks also supply water to the back mangroves. These insights in flow routing are promising for the future analysis of sediment input and distribution in mangroves

    Dreamers X Doers

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    The primary themes within Dreamers X Doers revolve around the need for social justice and the lack of collaboration between those who are doers and those who only dream of an ideal world. As a dreamer, I emphasize the desire for fellow dreamers to rise up and bring about the change they know needs to happen. I address the tendency of dreamers to live inside their own minds and to procrastinate, but I also make known the capacity for these dreamers to take part in the efforts towards social change that they feel so passionately about. All in all, dreamers and doers are not that different from one another. In fact, they need each other

    The Effects of Temperature on Evacuation Rates and Absorption Efficiency of Flathead Catfish

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    Knowledge of fish gastric evacuation rates are a necessary component for both field and laboratory studies when trying to understand feeding rates, modeling energy budgets, and understanding trophic dynamics of aquatic ecosystems. Many freshwater fish encounter a broad range of environmental temperatures across life history stages, but the mechanistic link between temperature and physiological processes often remains poorly understood. We designed three recirculating aquatic systems capable of rearing Flathead Catfish Plyodictis olivaris in order to quantify gastric evacuation rates and gross energy absorption at three temperatures (17º C, 22º C and 25º C). We examined the relationship between temperature and its influences on consumption, gastric evacuation rates, and meal passage through the intestines of juvenile Flathead Catfish fed a single ration of food. We then used bomb calorimetry to examine the absorption efficiencies of juvenile Flathead Catfish by quantifying the proportion of calories remaining in dissected stomach and intestinal contents through time and by treatment. Temperature significantly affected consumption, gastric evacuation rates, and the amount of calories remaining in the intestinal contents of juvenile Flathead Catfish. Insight into the gastric evacuation rates of juvenile Flathead Catfish provides managers with a better understanding of consumption demands of these important top predators. Furthermore, our results begin to shed light on the bioenergetics of juvenile Flathead Catfish. Advisor: Jamilynn B. Polett
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