893 research outputs found
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Geographic Information Systems, Evacuation Planning and Execution
Evacuation planning has for decades relied on the results derived from mathematical modeling and scenario development. While there exist many mathematical and simulation models dealing with evacuation planning most lack one or more critical components needed by the individuals or agencies responsible for removing people from harm’s way. Those critical components are real-time access to and representation of data to establish appropriate evacuation strategies. All the pieces for a real-time centralized evacuation system exist but have yet to be integrated as a single point system. The focus of this chapter is the underutilization of geographic information systems (GIS)
Rethinking Success: A Person-Based Approach to Service Learning
This thesis explores the nature of service learning projects that are structured to make interventions in rhetorical spheres and seek to achieve social change on a smaller scale rather striving for grander, or even systemic, change. In structuring community projects that include inherently limited interventions and equally limited goals, I argue that such projects should be open to immediate adjustments within themselves –to abandon any particular form or goal—to satisfy the immediate needs of the individuals served. I draw upon my work with a reintegration program for ex-offenders in Richmond, Virginia called Working with Conviction to help demonstrate that service learning constituents who create community projects need to be acutely attuned to the temporal and spatial constraints of any project, the ideological commitments of the relevant community, and the various locations of agency that can be affirmed and explored regarding the individuals served
Outflows and the Physical Properties of Quasars
We have investigated a sample of 5088 quasars from the Sloan Digital Sky
Survey Second Data Release in order to determine how the frequency and
properties of broad absorptions lines (BALs) depend on black hole mass,
bolometric luminosity, Eddington fraction (L/L_Edd), and spectral slope. We
focus only on high-ionization BALs and find a number of significant results.
While quasars accreting near the Eddington limit are more likely to show BALs
than lower systems, BALs are present in quasars accreting at only a
few percent Eddington. We find a stronger effect with bolometric luminosity,
such that the most luminous quasars are more likely to show BALs. There is an
additional effect, previously known, that BAL quasars are redder on average
than unabsorbed quasars. The strongest effects involving the quasar physical
properties and BAL properties are related to terminal outflow velocity. Maximum
observed outflow velocities increase with both the bolometric luminosity and
the blueness of the spectral slope, suggesting that the ultraviolet luminosity
to a great extent determines the acceleration. These results support the idea
of outflow acceleration via ultraviolet line scattering.Comment: Uses emulateapj.cls, 14 pages including 7 tables and 7 figures.
Accepted for publication in the Astrophysical Journal, Unabridged version of
Table 4 can be downloaded from http://physics.uwyo.edu/agn
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The Barcelona-Paris Connection: A Response to the Critical Framings of Ramon Casas and Santiago Rusiñol’s Engagement with French Art and Culture
In this thesis, I analyze the critical framings of modernista artists Ramon Casas\u27 (1866-1932) and Santiago Rusiñol\u27s (1861-1931) paintings and their connection with the artistic currents of nineteenth-century France in recent scholarship. I contend that contemporary reception of this aspect of their work has been conditioned and limited by the ideological view of Catalan modernity as a mere adoption and uneven application of Parisian models. This view echoes traditional framings of Spain by historians and writers as a peripheral and \u22backward\u22 country dependent upon Northern-European models of modernization. Using case studies, I offer an alternative approach to examine Casas and Rusiñol\u27s responsiveness to French art and culture that reinserts the artists\u27 agency when viewed through the lens of intercultural appropriation. Instead of marking their works as products of artistic \u22provincialism,\u22 I situate specific paintings by these artists as creative translations rather than derivative emulations of their artistic sources from abroad
Shocked POststarbust Galaxy Survey I: Candidate Poststarbust Galaxies with Emission Line Ratios Consistent with Shocks
[Abridged] The Shocked POststarburst Galaxy Survey (SPOGS) aims to identify
transforming galaxies, in which the nebular lines are excited via shocks
instead of through star formation processes. Utilizing the OSSY measurements on
the Sloan Digital Sky Survey Data Release 7 catalog, we applied Balmer
absorption and shock boundary criteria to identify 1,067 SPOG candidates
(SPOGs*) within z=0.2. SPOGs* represent 0.2% of the OSSY sample galaxies that
exceed the continuum signal-to-noise cut (and 0.7% of the emission line galaxy
sample). SPOGs* colors suggest that they are in an earlier phase of transition
than OSSY galaxies that meet an E+A selection. SPOGs* have a 13% 1.4GHz
detection rate from the Faint Images of the Radio Sky at Twenty centimeters
survey, higher than most other subsamples, and comparable only to
low-ionization nuclear emission line region hosts, suggestive of the presence
of active galactic nuclei. SPOGs* also have stronger NaD absorption than
predicted from the stellar population, suggestive of cool gas being driven out
in galactic winds. It appears that SPOGs* represent an earlier phase in galaxy
transformation than traditionally selected poststarburst galaxies, and that a
large proportion of SPOGs* also have properties consistent with disruption of
their interstellar media, a key component to galaxy transformation. It is
likely that many of the known pathways to transformation undergo a SPOG phase.
Studying this sample of SPOGs* further, including their morphologies, active
galactic nuclei properties, and environments, has the potential for us to build
a more complete picture of the initial conditions that can lead to a galaxy
evolving.Comment: 19 pages, 19 figures, 3 tables, accepted to ApJ Supplements (Apr 13),
full sample is available on www.spogs.or
A Comparison of Atomic Oxygen Erosion Yields of Carbon and Selected Polymers Exposed in Ground Based Facilities and in Low Earth Orbit
A comparison of the relative erosion yields (volume of material removed per oxygen atom arriving) for FEP Teflon, polyethylene, and pyrolytic graphite with respect to Kapton HN was performed in an atomic oxygen directed beam system, in a plasma asher, and in space on the EOIM-III (Evaluation of Oxygen Interaction with Materials-III) flight experiment. This comparison was performed to determine the sensitivity of material reaction to atomic oxygen flux, atomic oxygen fluence, and vacuum ultraviolet radiation for enabling accurate estimates of durability in ground based facilities. The relative erosion yield of pyrolytic graphite was found not to be sensitive to these factors, that for FEP was sensitive slightly to fluence and possibly ions, and that for polyethylene was found to be partially VUV and flux sensitive but more sensitive to an unknown factor. Results indicate that the ability to use these facilities for material relative durability prediction is great as long as the sensitivity of particular materials to conditions such as VUV, and atomic oxygen flux and fluence are taken into account. When testing materials of a particular group such as teflon, it may be best to use a witness sample made of a similar material that has some available space data on it. This would enable one to predict an equivalent exposure in the ground based facility
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