1,612 research outputs found

    Impacts of Cattle Grazing Management on Sediment and Phosphorus Loads in Surface Waters

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    In 2001 (yr 1), 2002 (yr 2), and 2003 (yr 3), three blocks of five 1-ac paddocks were grazed by beef cows on hills at the Iowa State University Rhodes Research and Demonstration Farm to determine the effects of grazing management on phosphorus (P) and sediment runoff from pastureland. Grazing management treatments included an ungrazed control (UG), summer hay harvest with winter stockpiled grazing (HS), grazing by continuous stocking to a residual sward height of 2 in. (2C), rotational stocking to a residual sward height of 2 in. (2R), and rotational stocking to a residual sward height of 4 in (4R). At four times (late spring, mid-summer, early autumn, and early the subsequent spring) in each year, rainfall simulations were conducted at 6 sites within each paddock. Rainfall simulators dripped at a rate of 2.8 in./hr over a 5.4-ft2 area for a period of 1.5 hours. Runoff was collected and analyzed for total sediment, total P, and total soluble P. Simultaneous to each rainfall simulation, ground cover, penetration resistance, surface roughness, slope, the contents of P and moisture of the soil, sward height and forage mass were measured. Sediment flow was not affected by forage management practice. There was no difference between UG, HS, 4R in the amount of total P or soluble P lost in runoff, but greater amounts of total and soluble P were lost from 2C and 2R than from the other management practices (P\u3c0.05). A greater amount of sediment was lost from the pastures during the late spring period than during other parts of the year (P\u3c0.05). Losses of sediment, total P, and soluble P from pastures can be controlled by suitable grazing management practices

    Modeling Phosphorus Capture by Plants Growing in a Multispecies Riparian Buffer

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    The NST 3.0 mechanistic nutrient uptake model was used to explore P uptake to a depth of 120 cm over a 126 d growing season in simulated buffer communities composed of mixtures of cottonwood (Populus deltoids Bartr.), switchgrass (Panicum virgatum L.), and smooth brome (Bromus inermis Leyss). Model estimates of P uptake from pure stands of smooth brome and cottonwood were 18.9 and 24.5 kg ha−1, respectively. Uptake estimates for mixed stands of trees and grasses were intermediate to pure stands. A single factor sensitivity analysis of parameters used to calculate P uptake for each cover type indicated that Imax, k, ro, and Lo were consistently the most responsive to changes ranging from −50% to +100%. Model exploration of P uptake as a function of soil depth interval indicated that uptake was highest in the 0–30 cm intervals, with values ranging from 85% of total for cottonwood to 56% for switchgrass

    Assembly and Certification of ATLAS Muon Stations for the Middle and Outer Barrel at CERN

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    Roughly 400 of the approximately 700 muon stations of the ATLAS barrel belong to the middle and outer layer. Barrel Middle and Barrel Outer stations consist of both an MDT chamber and one or two RPC planes delivering the level-1 trigger information. While MDT chambers and individual RPC units are constructed at their home institutes, the assembly of the RPCs into planes, including the final cabling and the mounting of the trigger electronics, as well as the integration of MDTs and RPCs into muon stations takes place at CERN. MDT chambers, RPC planes and the completed stations have to pass a series of tests before being declared 'ready-for-installation'. Final certification criteria is the passing of a one-day cosmic ray test, for which a special setup has been built in building 899 (BB5). This note gives an overview over the work carried out in BB5, with emphasis on the cosmic ray test. Examples of abnormal chamber behavior will be discussed and a summary of common mistakes in station assembly or chamber cabling will be given. A second focus of the note is on the statistical analysis of the certification results

    Spatial Motion Doodles: Sketching Animation in VR Using Hand Gestures and Laban Motion Analysis

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    International audienceWe present a method for easily drafting expressive character animation by playing with instrumented rigid objects. We parse the input 6D trajectories (position and orientation over time)-called spatial motion doodles-into sequences of actions and convert them into detailed character animations using a dataset of parameterized motion clips which are automatically fitted to the doodles in terms of global trajectory and timing. Moreover, we capture the expres-siveness of user-manipulation by analyzing Laban effort qualities in the input spatial motion doodles and transferring them to the synthetic motions we generate. We validate the ease of use of our system and the expressiveness of the resulting animations through a series of user studies, showing the interest of our approach for interactive digital storytelling applications dedicated to children and non-expert users, as well as for providing fast drafting tools for animators

    Measurement campaign on the JRC Ispra decommissioning site

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    The purpose of this document is to describe the measurement campaign with the Free Release Measurement Facility (FRMF) at building 41m “Interim Storage Facility” (ISF) of material clearable according to existing licenses as part of the collaborative research project MetroDecom. The description of the measurement campaign includes the technical requirements and safety implementations necessary for carrying out this project. The Free Release Measurement Facility (FRMF) was designed as a state of the art facility for measurement of low gamma-ray activity waste packages. Gamma spectrometric method for free release measurment was developed. The complemented with passive neutron counting method. The both methods are used for different nuclide contents in the waste and are complementary. For this purpose the instrument incorporates: — Three passive neutron counters (design of JRC) — A gamma-ray detection system HPGe Interchangeable Detector Module IDM-200-V (ORTEC) — NuDET Plastic Scintillation Detectors (design of NUVIA) Decommissioning unit delivered seventy containers with material clearable according to existing JRC licenses. JRC G.II.7 performed the testing of the free release measurement system. The document contains the overview of that measurement campaign. The detailed measurement protocols, spectra generated by FRMF software are shared with MetroDecom Partners.JRC.G.II.7-Nuclear securit
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