843 research outputs found

    Epoxy-coated containers easily opened by wire band

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    Epoxy coating reduces punctures, abrasions, and contamination of synthetic cellular containers used for shipping and storing fragile goods and equipment. A wire band is wound around the closure joint, followed by the epoxy coating. The container can then be easily opened by pulling the wire through the epoxy around the joint

    Potential Surface Water Storage Capacities of Various Contoured Geometric Shapes

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    Since the beginning of time man has been concerned with floods and surface runoff. Several floods are recorded in the Bible, including one flood so large that it would have destroyed the world if special provisions had not been made. Runoff can affect man\u27s food, clothing, and shelter and can even take his life. The storage of water on the field in order to prevent runoff has been practiced for many years. The concept of storing water where it falls is not new. Contouring practices store some water in place. Gradient terraces also provide a limited amount of storage of water, but the storage is concentrated and for a short duration of time. Channel-type level terraces store a considerable quantity of water; and if it would he practical to place these terraces close together, theoretically, they would tend to store water over the entire surface of the field. This study is a basic study to determine the various geometric shapes obtained when bedding: conventional tillage - plowing, disking and surface planting - and listing are used on the contour and their effect on surface water storage, soil mciistu.re, terrace spacing and crop yield. The potential surface water storage capacities of six different geometric shapes are studied in this investigation. The results of these water holding capacities of these geometric shapes are then related to their ability to reduce runoff and soil erosion

    Generation of spiral bevel gears with zero kinematical errors and computer aided tooth contact analysis

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    Kinematic errors in spiral bevel gears are a major source of noise and vibrations in transmissions. A method for the generation of Gleason's spiral bevel gears which provides conjugated gear tooth surfaces and an improved bearing contact was developed. A computer program for the simulation of meshing, misalignment, and bearing contact was written

    Global Assimilation of Loon Stratospheric Balloon Observations and Their Trajectories Relative to Tropical Waves

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    Project Loon has an overall goal of providing worldwide internet coverage using a network of long-duration super-pressure balloons. Beginning in 2013, Loon has launched over 1600 balloons from multiple tropical and middle latitude locations. These GPS tracked balloon trajectories provide lower stratospheric wind information over the oceans and remote land areas where traditional radiosonde soundings are sparse, thus providing unique coverage of lower stratospheric winds. To fully investigate these Loon winds we: 1) compare the Loon winds to winds produced by a global data assimilation system (DAS: NASA GEOS) and 2) assimilate the Loon winds into the same comprehensive DAS. During May through December 2016 Loon balloons were often able to remain near the equator by selectively adjusting the Loon altitude. Our results based on global wind analyses show that the expected mean poleward motion from the Brewer-Dobson circulation can be circumvented by vertically adjusting the Loon altitudes with the phasing with the meridional wind of equatorial Rossby waves, allowing the Loon balloons to remain in the tropics

    Spiral bevel and circular arc helical gears: Tooth contact analysis and the effect of misalignment on circular arc helical gears

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    A computer aided method for tooth contact analysis was developed and applied. Optimal machine-tool settings for spiral bevel gears are proposed and when applied indicated that kinematic errors can be minimized while maintaining a desirable bearing contact. The effect of misalignment for circular arc helical gears was investigated and the results indicted that directed pinion refinishing can compensate the kinematic errors due to misalignment

    Intraseasonal and Interannual Variability of the Quasi-Two Day Wave in the Northern Hemisphere Summer Mesosphere

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    This study uses global synoptic meteorological fields from a high-altitude data assimilation system to investigate the spatial and temporal characteristics of the quasi-2 day wave (Q2DW) and migrating diurnal tide during the Northern Hemisphere summers of 2007, 2008, and 2009. By applying a 2-dimensional fast Fourier transform to meridional wind and temperature fields, we are able to identify Q2DW source regions and to diagnose propagation of Q2DW activity into the upper mesosphere and lower thermosphere. We find that Q2DW is comprised primarily of westward propagating zonal wavenumber 3 and wavenumber 4 components that originate from within baroclinically unstable regions along the equatorward flank of the summer midlatitude easterly jet. Amplitude variations of wavenumbers 3 and 4 tend to be anti-correlated throughout the summer, with wavenumber 3 maximizing in July and wavenumber 4 maximizing in late June and early August. Monthly mean Q2DW amplitudes between 30 50N latitude are largest when diurnal tidal amplitudes are smallest and vice versa. However, there is no evidence of any rapid amplification of the Q2DW via nonlinear interaction with the diurnal tide. Instead, variations of Q2DW amplitudes during July are closely linked to variations in the strength and location of the easterly jet core from one summer to the next, with a stronger jet producing larger Q2DW amplitudes. Linear instability model calculations based on the assimilated wind fields find fast growing zonal wavenumber 3 and 4 modes with periods near 2 days in the vicinity of the easterly jet

    New generation methods for spur, helical, and spiral-bevel gears

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    New methods for generating spur, helical, and spiral-bevel gears are proposed. These methods provide the gears with conjugate gear tooth surfaces, localized bearing contact, and reduced sensitivity to gear misalignment. Computer programs have been developed for simulating gear meshing and bearing contact

    Dynamic concentration of motors in microtubule arrays

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    We present experimental and theoretical studies of the dynamics of molecular motors in microtubule arrays and asters. By solving a convection-diffusion equation we find that the density profile of motors in a two-dimensional aster is characterized by continuously varying exponents. Simulations are used to verify the assumptions of the continuum model. We observe the concentration profiles of kinesin moving in quasi two-dimensional artificial asters by fluorescent microscopy and compare with our theoretical results.Comment: 4pages, 4 figures revte

    Using Continuous Response Assessment to Evaluate the Effectiveness of Extension Education Products

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    The case study addressed in this article illustrates the value of continuous response measurement (CRM) for testing and refining messages produced for distribution to Extension audiences. We used CRM to evaluate the responses of Extension educators and Natural Resources Conservation Service technical service providers to a video describing greenhouse gas mitigation techniques. By using this assessment method, message producers can identify elements in a video that elicit strong positive or negative responses and then refine communication activities accordingly. Our study highlights the potential of CRM for informing how Extension education products and materials may be preevaluated to ensure more widespread acceptance and use of final versions by intended audiences
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