5,829 research outputs found

    TB108: Chemical and Physical Properties of the Becket, Colton, Finch, Lyman, Masardis, Naumburg, and Skerry Soil Mapping Units

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    Soil morphology and soil characterization studies were done on seven soil mapping units in Maine. Soil profiles were selected, described and sampled jointly by soil scientists from the Soil Conservation Service, USDA and the Maine Agricultural Experiment Station. Chemical and physical measurements of each soil mapping unit were made in the laboratory. Soil profile description and the laboratory determinations are presented for each sample site.https://digitalcommons.library.umaine.edu/aes_techbulletin/1092/thumbnail.jp

    Real-time standard scan plane detection and localisation in fetal ultrasound using fully convolutional neural networks

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    Fetal mid-pregnancy scans are typically carried out according to fixed protocols. Accurate detection of abnormalities and correct biometric measurements hinge on the correct acquisition of clearly defined standard scan planes. Locating these standard planes requires a high level of expertise. However, there is a worldwide shortage of expert sonographers. In this paper, we consider a fully automated system based on convolutional neural networks which can detect twelve standard scan planes as defined by the UK fetal abnormality screening programme. The network design allows real-time inference and can be naturally extended to provide an approximate localisation of the fetal anatomy in the image. Such a framework can be used to automate or assist with scan plane selection, or for the retrospective retrieval of scan planes from recorded videos. The method is evaluated on a large database of 1003 volunteer mid-pregnancy scans. We show that standard planes acquired in a clinical scenario are robustly detected with a precision and recall of 69 % and 80 %, which is superior to the current state-of-the-art. Furthermore, we show that it can retrospectively retrieve correct scan planes with an accuracy of 71 % for cardiac views and 81 % for non-cardiac views

    Flight tests of IFR landing approach systems for helicopters

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    Joint NASA/FAA helicopter flight tests were conducted to investigate airborne radar approaches (ARA) and microwave landing system (MLS) approaches. Flight-test results were utilized to prove NASA with a data base to be used as a performance measure for advanced guidance and navigation concepts, and to provide FAA with data for establishment of TERPS criteria. The first flight-test investigation consisted of helicopter IFR approaches to offshore oil rigs in the Gulf of Mexico, using weather/mapping radar, operational pilots, and a Bell 212 helicopter. The second flight-test investigation consisted of IFR MLS approaches at Crows Landing (near Ames Research Center), with a Bell UH-1H helicopter, using NASA, FAA, and operational industry pilots. Tests are described and results discussed

    Finite element analysis of stress distribution and the effects of geometry in a laser-generated single-stage ceramic tile grout seal using ANSYS

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    Optimisation of the geometry (curvature of the vitrified enamel layer) of a laser-generated single-stage ceramic tile grout seal has carried out with a finite element (FE) model. The overall load bearing capacities and load-displacement plots of three selected geometries were determined experimentally by the indentation technique. Simultaneously, a FE model was developed utilising the commercial ANSYS package to simulate the indentation. Although the load-displacement plots generated by the FE model consistently displayed stiffer identities than the experimentally obtained results, there was reasonably close agreement between the two sets of results. Stress distribution profiles of the three FE models at failure loads were analysed and correlated so as to draw an implication on the prediction of a catastrophic failure through an analysis of FE-generated stress distribution profiles. It was observed that although increased curvatures of the vitrified enamel layer do enhance the overall load-bearing capacity of the single-stage ceramic tile grout seal and bring about a lower nominal stress, there is a higher build up in stress concentration at the apex that would inevitably reduce the load-bearing capacity of the enamel glaze. Consequently, the optimum geometry of the vitrified enamel layer was determined to be flat

    Modelling the spread of American foulbrood in honeybees

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    We investigate the spread of American foulbrood (AFB), a disease caused by the bacterium Paenibacillus larvae, that affects bees and can be extremely damaging to beehives. Our dataset comes from an inspection period carried out during an AFB epidemic of honeybee colonies on the island of Jersey during the summer of 2010. The data include the number of hives of honeybees, location and owner of honeybee apiaries across the island. We use a spatial SIR model with an underlying owner network to simulate the epidemic and characterize the epidemic using a Markov chain Monte Carlo (MCMC) scheme to determine model parameters and infection times (including undetected ā€˜occultā€™ infections). Likely methods of infection spread can be inferred from the analysis, with both distance- and owner-based transmissions being found to contribute to the spread of AFB. The results of the MCMC are corroborated by simulating the epidemic using a stochastic SIR model, resulting in aggregate levels of infection that are comparable to the data. We use this stochastic SIR model to simulate the impact of different control strategies on controlling the epidemic. It is found that earlier inspections result in smaller epidemics and a higher likelihood of AFB extinction

    A contact-based social network of lizards is defined by low genetic relatedness among strongly connected individuals

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    Author version made available in accordance with the Publisher's policy, after an embargo period of 24 months from the date of publication. Ā© 2015. Licensed under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/Social organization is widespread; even largely solitary species must organize themselves to enable contacts with mates and reduce competition with conspecifics. Although the forms of social structure can be subtle in solitary species, understanding the factors that influence them may be important for understanding how different forms of social organization evolved. We investigated the influence of genetic relatedness and spatial structure on social associations in a solitary living Australian scincid lizard, Tiliqua rugosa. We derived the genetic relatedness of 46 lizards from analysis of genotypes at 15 microsatellite DNA loci, and described social networks from GPS locations of all the lizards every 10 min for 81 days during their main activity period of the year. We found that connected male dyads were significantly more related than expected by chance, whereas connected maleā€“female and femaleā€“female dyads had lower relatedness than expected. Among neighbouring maleā€“male and maleā€“female dyads, the strongest social relationships were between lizards that were the least related. Explanations of this pattern may include the avoidance of inbreeding in maleā€“female dyads, or the direction of aggressive behaviour towards less related individuals in maleā€“male dyads. Observed social associations (inferred through synchronous spatial proximity) were generally lower than expected from null models derived from home range overlap, and many close neighbours did not make social contact. This supports our hypothesis for the presence of deliberate avoidance between some neighbouring individuals. We suggest that lizards can discriminate between different levels of relatedness in their neighbours, directing their social interactions towards those that are less related. This highlights differences in how social associations are formed between species that are solitary (where associations form between unrelated conspecifics) and species that maintain stable social groups structured by kinship.Our sleepy lizard research was funded by the Australian Research Council

    Investigation of phonon behavior in Pr2NiMnO6 by micro-Raman spectroscopy

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    The temperature dependence of phonon excitations and the presence of spin phonon coupling in polycrystalline Pr2NiMnO6 samples were studied using micro-Raman spectroscopy and magnetometry. Magnetic properties show a single ferromagnetic-to-paramagnetic transition at 228 K and a saturation magnetization close to 4.95 \muB/f.u.. Three distinct Raman modes at 657, 642, and 511 cm-1 are observed. The phonon excitations show a clear hardening due to anharmonicity from 300 K down to 10 K. Further, temperature dependence of the 657 cm-1 mode shows only a small softening. This reflects the presence of a relatively weak spin-phonon coupling in Pr2NiMnO6 contrary to other double perovskites previously studied.Comment: 10 pages, 4 fig
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