2,184 research outputs found
In Pursuit Of General Behavioral Relations
Efforts to develop behavioral technologies from advances in basic research assume that results from studies with nonhuman subjects can, in some instances, be applied to human behavior. The behavioral principles likely to be most useful for application are those that represent robust general behavioral relations. Basic and applied research on behavioral momentum suggests that there is a general behavioral relation between the persistence of behavior and the rate of reinforcement obtained in a given situation. Understanding the factors that affect behavioral persistence may have important implications for applied behavior analysts that justify studies aimed at establishing the generality and limits of the functional relation between reinforcement rate and behavioral persistence. Strategies for establishing the generality of behavioral relations are reviewed, followed by a brief summary of the evidence for the generality of behavioral momentum
Three New Cool Brown Dwarfs Discovered with the Wide-field Infrared Survey Explorer (WISE) and an Improved Spectrum of the Y0 Dwarf WISE J041022.71+150248.4
As part of a larger search of Wide-field Infrared Survey Explorer (WISE) data
for cool brown dwarfs with effective temperatures less than 1000 K, we present
the discovery of three new cool brown dwarfs with spectral types later than T7.
Using low-resolution, near-infrared spectra obtained with the NASA Infrared
Telescope Facility and the Hubble Space Telescope we derive spectral types of
T9.5 for WISE J094305.98+360723.5, T8 for WISE J200050.19+362950.1, and Y0: for
WISE J220905.73+271143.9. The identification of WISE J220905.73+271143.9 as a Y
dwarf brings the total number of spectroscopically confirmed Y dwarfs to
seventeen. In addition, we present an improved spectrum (i.e. higher
signal-to-noise ratio) of the Y0 dwarf WISE J041022.71+150248.4 that confirms
the Cushing et al. classification of Y0. Spectrophotometric distance estimates
place all three new brown dwarfs at distances less than 12 pc, with WISE
J200050.19+362950.1 lying at a distance of only 3.9-8.0 pc. Finally, we note
that brown dwarfs like WISE J200050.19+362950.1 that lie in or near the
Galactic plane offer an exciting opportunity to measure their mass via
astrometric microlensing.Comment: Accepted for publication in the Astronomical Journa
Portfolio assessment in a reading-writing classroom
The purpose of this paper is to present the rationale for portfolios as a part of the qualitative assessment of students\u27 emerging literacy. Ways to develop a portfolio and to use this technique for assessment will be discussed
Discovery of Four High Proper Motion L Dwarfs, Including a 10 pc L Dwarf at the L/T Transition
We discover four high proper motion L dwarfs by comparing the Wide-field
Infrared Survey Explorer (WISE) to the Two Micron All Sky Survey (2MASS). WISE
J140533.32+835030.5 is an L dwarf at the L/T transition with a proper motion of
0.85+/-0.02" yr^-1, previously overlooked due to its proximity to a bright star
(V=12 mag). From optical spectroscopy we find a spectral type of L8, and from
moderate-resolution J band spectroscopy we find a near-infrared spectral type
of L9. We find WISE J140533.32+835030.5 to have a distance of 9.7+/-1.7 pc,
bringing the number of L dwarfs at the L/T transition within 10 pc from six to
seven. WISE J040137.21+284951.7, WISE J040418.01+412735.6, and WISE
J062442.37+662625.6 are all early L dwarfs within 25 pc, and were classified
using optical and low-resolution near-infrared spectra. WISE
J040418.01+412735.6 is an L2 pec (red) dwarf, a member of the class of
unusually red L dwarfs. We use follow-up optical and low-resolution
near-infrared spectroscopy to classify a previously discovered (Castro & Gizis
2012) fifth object WISEP J060738.65+242953.4 as an (L8 Opt/L9 NIR), confirming
it as an L dwarf at the L/T transition within 10 pc. WISEP J060738.65+242953.4
shows tentative CH_4 in the H band, possibly the result of unresolved binarity
with an early T dwarf, a scenario not supported by binary spectral template
fitting. If WISEP J060738.65+242953.4 is a single object, it represents the
earliest onset of CH_4 in the H band of an L/T transition dwarf in the SpeX
Library. As very late L dwarfs within 10 pc, WISE J140533.32+835030.5 and WISEP
J060738.65+242953.4 will play a vital role in resolving outstanding issues at
the L/T transition.Comment: 45 pages, 12 figures, accepted for publication in Ap
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Assigning Water Levels and Ground Water Depletions in the Ogallala Aquifer
The purpose of this report is to evaluate the assignment of water levels in monitor wells in order to create ground-water depletion maps of the Panhandle Ground Water Conservation District No. 3 (PGWCD No. 3). Ground-water depletion maps document and quantify the decrease in ground-water resources in the PGWCD No. 3 by monitoring the historical lowstand of water levels in the Ogallala aquifer. They are used to assign water-level declines to eligible properties for Federal tax credit. Because area landowners rely on these maps for such assignments and because the maps are used in documenting ground-water resources, the procedures used in their creation should be accurate, fair, and timely. The PGWCD No. 3 currently uses a floating, 5-yr, back- calculated average to guide water-level assignments used in generating ground-water-depletion maps. This approach, however, may significantly underestimate water-level declines in individual wells and may give nonreproducible results from well to well. During this study, we assessed the limitations of this approach, described the complications of assigning water levels, and evaluated alternative approaches to define water levels used in determining depletions more accurately. Our goal was to develop a defensible approach that more accurately represents water levels in the Ogallala aquifer.
This report specifies how water levels should be assigned in monitor wells in order to minimize errors and provide the most hydrologically reasonable, defensible, and accurate water- level declines. A subsequent report will discuss an automated and statistically rigorous method for assigning depletions to individual properties. These reports will allow the PGWCD No. 3 to maximize the quality of the data used in depletion analysis and to minimize the errors and time used in assigning depletions in the district.Bureau of Economic Geolog
Comment on 'Computation of choked and supersonic turbomachinery flows by a modified potential method'
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76485/1/AIAA-9485-236.pd
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Hydrologic and Hydrochemical Results from Pumping Tests Conducted at the 11-14 Pond, Pantex Plant, Texas
Results from pumping tests conducted in monitoring wells located at the 11-14 pond significantly increase our understanding of the hydrogeology of perched aquifers at the Pantex Plant, the U.S. Department of Energy weapons plant serving as the final assembly and disassembly point for the nuclear arsenal and also as a test facility for high explosives. The mean transmissivity and hydraulic conductivity calculated for all four wells based on delayed yield analyses were 488 ± 250 ft^2 d^-1 and 33.8 ± 17.9 ft d^-1 (45.3 ± 23.2 m^2 d^-1 and 10.3 ± 5.4 m d^-1), respectively. On the basis of these hydraulic conditions, a ground-water velocity in the 11-14 pond area of 0.85 ft d^-1 (0.26 m d^-1) was calculated.
Results of chemical analyses on water samples collected at three different times during the pumping test were relatively consistent. This consistency indicates that, within the volume of the perched aquifer from which water was pumped, no compositional stratification or lateral compositional trends could be conclusively identified.Bureau of Economic Geolog
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