17,467 research outputs found
Superconducting Surface Impedance under Radiofrequency Field
Based on BCS theory with moving Cooper pairs, the electron states
distribution at 0K and the probability of electron occupation with finite
temperature have been derived and applied to anomalous skin effect theory to
obtain the surface impedance of a superconductor under radiofrequency (RF)
field. We present the numerical results for Nb and compare these with
representative RF field-dependent effective surface resistance measurements
from a 1.5 GHz resonant structure
Arkansas Wheat Cultivar Performance Tests 2013-2014
Wheat cultivar performance tests are conducted each year in Arkansas by the Arkansas Agricultural Experiment Station, Department of Crop, Soil and Environmental Sciences. The tests provide information to companies developing cultivars and/or marketing seed within the state and aid the Arkansas Cooperative Extension Service in formulating cultivar recommendations for small-grain producers
Arkansas Wheat Cultivar Performance Tests 2018-2019
Wheat cultivar performance tests are conducted each year in Ark- ansas by the University of Arkansas System Division of Agriculture’s Arkansas Agricultural Experiment Station, Department of Crop, Soil and Environmental Sciences. The tests provide information to companies developing cultivars and marketing seed within the state and aid the Arkansas Cooperative Extension Service in formulating cultivar recommendations for small-grain producers. The tests are conducted at the Northeast Research and Extension Center at Keiser, the Vegetable Substation near Kibler, the Lon Mann Cotton Research Station near Marianna, the Newport Extension Center near Newport, the Rohwer Research Station near Rohwer, the Pine Tree Research Station near Colt, and the Hope Research and Extension Center. In addition, entries are evaluated in a stripe rust (Puccinia striiformis f.sp. tritici) inoculated nursery in Fayetteville and a Fusarium head blight (FHB) inoculated nursery in Newport and Fayetteville. Specific location and cultural practice information accompany each table
Arkansas Wheat Cultivar Performance Tests 2016-2017
Wheat cultivar performance tests are conducted each year in Arkansas by the University of Arkansas System Division of Agriculture’s Arkansas Agricultural Experiment Station, Department of Crop, Soil and Environmental Sciences. The tests provide information to companies developing cultivars and marketing seed within the state and aid the Arkansas Cooperative Extension Service in formulating cultivar recommendations for small-grain producers
Arkansas Wheat Cultivar Performance Tests 2011-2012
Wheat cultivar performance tests are conducted each year in Arkansas by the Arkansas Agricultural Experiment Station, Department of Crop, Soil and Environmental Sciences. The tests provide information to companies developing cultivars and/or marketing seed within the state and aid the Arkansas Cooperative Extension Service in formulating cultivar recommendations for small-grain producers
Helicopter Anti-Torque System Using Strakes
A helicopter is disclosed with a system for controlling main-rotor torque which reduces the power and size requirements of conventional anti-torque means. The torque countering forces are generated by disrupting the main rotor downwash flowing around the fuselage. The downwash flow is separated from the fuselage surface by a strake positioned at a specified location on the fuselage. This location is determined by the particular helicopter wash pattern and fuselage configuration, generally being located between 20 deg before top dead center (TDC) and 80 deg from TDC on the fuselage side to which the main rotor blade approaches during rotation. The strake extends along the fuselage from the cabin section to the aft end and can be continuous or separated for aerodynamic surfaces such as a horizontal stabilizer
An on-board near-optimal climb-dash energy management
On-board real time flight control is studied in order to develop algorithms which are simple enough to be used in practice, for a variety of missions involving three dimensional flight. The intercept mission in symmetric flight is emphasized. Extensive computation is required on the ground prior to the mission but the ensuing on-board exploitation is extremely simple. The scheme takes advantage of the boundary layer structure common in singular perturbations, arising with the multiple time scales appropriate to aircraft dynamics. Energy modelling of aircraft is used as the starting point for the analysis. In the symmetric case, a nominal path is generated which fairs into the dash or cruise state. Feedback coefficients are found as functions of the remaining energy to go (dash energy less current energy) along the nominal path
Energy management of three-dimensional minimum-time intercept
A real-time computer algorithm to control and optimize aircraft flight profiles is described and applied to a three-dimensional minimum-time intercept mission
Ambivalent sexism and perceptions of men and women who violate gendered family roles
This study draws on ambivalent sexism theory to explore the role of benevolent and hostile gender attitudes in determining perceptions of individuals who comply with traditional gender roles or violate them. Three hundred and eleven participants were presented with a description of a male or a female target who was either a primary breadwinner or a primary caregiver. As hypothesized, hostile sexism predicted more negative perceptions of a female breadwinner, whereas benevolent sexism predicted more positive perceptions of a female caregiver. Moreover, participants who endorsed hostile attitudes toward men reacted more positively to a nontraditional male caregiver, whereas those who endorsed benevolent attitudes toward men reacted more negatively to a male caregiver. Implications regarding the nature of ambivalent gender attitudes are discussed
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