80,353 research outputs found
Design definition of a mechanical capacitor
A design study and analyses of a 10 kW-hr, 15 kW mechanical capacitor system was studied. It was determined that magnetically supported wheels constructed of advanced composites have the potential for high energy density and high power density. Structural concepts are analyzed that yield the highest energy density of any structural design yet reported. Particular attention was paid to the problem of 'friction' caused by magnetic and I to the second power R losses in the suspension and motor-generator subsystems, and low design friction levels have been achieved. The potentially long shelf life of this system, and the absence of wearing parts, provide superior performance over conventional flywheels supported with mechanical bearings. Costs and economies of energy storage wheels were reviewed briefly
Capillary Waves at Liquid/Vapor Interfaces: A Molecular Dynamics Simulation
Evidence for capillary waves at a liquid/vapor interface are presented from
extensive molecular dynamics simulations of a system containing up to 1.24
million Lennard-Jones particles. Careful measurements show that the total
interfacial width depends logarithmically on , the length of the
simulation cell parallel to the interface, as predicted theoretically. The
strength of the divergence of the interfacial width on depends
inversely on the surface tension . This allows us to measure
two ways since can also be obtained from the difference in the
pressure parallel and perpendicular to the interface. These two independent
measures of agree provided that the interfacial order parameter
profile is fit to an error function and not a hyperbolic tangent, as often
assumed. We explore why these two common fitting functions give different
results for
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EOR as sequestration: Geoscience perspective
CO2 Enhanced Oil Recovery (EOR) has a development and operational history several decades longer than geologic sequestration of CO2 designed to benefit the atmosphere and provides much of the experience on which confidence in the newer technology is based. With modest increases in surveillance and accounting, future CO2 EOR using anthropogenic CO2 (CO2-A) captured to decrease atmospheric emissions can be used as part of a sequestration program.Bureau of Economic Geolog
Short and long distance translocations: Movement and survival in eastern box turtles (_Terrapene carolina carolina_)
*Background/Question/Methods*

Human development represents a serious threat to wildlife populations through continued habitat loss and incidental mortality from construction activities. Resource managers responsible for protecting species with legal status or high public profile are faced with difficult decisions on how to best manage populations located in construction zones. One approach to mitigate mortalities is to relocate individuals. The effectiveness of translocation for reptiles and amphibians has been questioned, with studies often reporting higher mortality and increased movements of translocated individuals. Translocations of reptiles and amphibians have primarily involved moving animals long distances, well beyond an individual’s home range. For reptiles this means finding new nesting, foraging, and overwintering sites, which may be problematic. Moving individuals only short distances, within their home range, may reduce those problems. As part of the mitigation plan for a highway construction project in central Maryland, groups of eastern box turtles (Terrapene carolina carolina) were translocated both short distances (<0.5km), and long distances (~5km). To investigate differences in survival and movement patterns among long distance translocation, short distance translocation, and non-translocation groups, I tracked 94 turtles (31 long distance translocation, 29 short distance translocation, and 34 non-translocation) using radio telemetry. 

*Results/Conclusions*

Eleven animals died during the first activity season after translocation (April through November 2008). The mortalities included two long distance translocation, six short distance translocation, and three non-translocation animals. The causes of mortality included road kill, construction activity, and unknown (1, 4, and 6 mortalities respectively). All construction related mortalities were a result inadequate exclusion fencing to keep turtles from trespassing back onto the construction site. All mortalities due to construction were either non-translocation or short distance translocation animals. Eleven other individuals were located at least once within the construction zone, suggesting that without our intervention mortality rates would have been much higher. Preliminary results for movement show that turtles in the non-translocation group had the lowest average movements while long distance translocation animals had the greatest average movements. Long distance translocation turtles also chose overwintering sites farther away from their initial overwintering sites than either short distance translocation or non-translocation turtles (average distance from original site of 261.8m, 155.6m, and 124.3m respectively). This suggests that movement patterns of short distance translocation turtles are more like native turtles.

Data documentation for the bare soil experiment at the University of Arkansas
The reflectivities of several controlled moisture test plots were investigated. These test plots were of a similar soil texture which was clay loam and were prepared to give a desired initial soil moisture and density profile. Measurements were conducted on the plots as the soil water redistributed for both long term and diurnal cycles. These measurements included reflectivity, gravimetric and volumetric soil moisture, soil moisture potential, and soil temperature
Long-term Effects of Tillage on the Retention and Transport of Soil Water
Quantitative measurements were made of the physical and chemical properties of two virgin prairie soils, Crowley and Jay, that remain in their native Arkansas environments and of similar soils that had been tilled extensively. Comparisons were made of soil properties at several depths. When compared with the tilled soils the virgin soils had higher organic matter contents, saturated hydraulic conductivities and water retained at several applied pressures. Bulk densities and hydraulic resistances were lower in the virgin soils. For the Crowley silt loam, values of pH and elemental contents of the virgin soil were higher than those of the tilled soil. Determinations also were made of the effects of a 14-year addition of winter cover crops on a Dubbs-Dundee soil in continuous cotton production. In general, the winter cover crops tended to increase hydraulic conductivity~. ·porosity and organic matter content. These results indicated that the detrimental effects of long-term tillage on soil hydraulic properties could partially be overcome with the planting of these crops during the winter. However, the rate of improvement in the hydraulic properties was not dramatic
Soil erosion by landing rockets Final report
Cratering effect of descending rocket exhaust expected from soft earth landin
Day-to-day Variability of Stuttering
Variability has long been known to be a primary feature of the disorder of stuttering (Bloodstein & Bernstein Ratner, 2008; Costello & Ingham, 1984; Yaruss, 1997a, 1997b). Many factors that affect variability have been investigated (Brown, 1937; Johnson & Brown, 1935; Quarrington, Conway, & Siegel, 1962) yet the typical range of variability experienced by speakers remains unknown. This study will examine the speech of six adult speakers in three spontaneous speaking situations and two reading tasks. The frequency, duration, and types of stuttered events that occur on the tasks will be compared within and between speakers. The focus will be on describing variability in stuttering frequency and duration within speakers and attempting to detect consistent patterns between speakers
Correlation length scalings in fusion edge plasma turbulence computations
The effect of changes in plasma parameters, that are characteristic near or
at an L-H transition in fusion edge plasmas, on fluctuation correlation lengths
are analysed by means of drift-Alfven turbulence computations. Scalings by
density gradient length, collisionality, plasma beta, and by an imposed shear
flow are considered. It is found that strongly sheared flows lead to the
appearence of long-range correlations in electrostatic potential fluctuations
parallel and perpendicular to the magnetic field.Comment: Submitted to "Plasma Physics and Controlled Fusion
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