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Painting in 2010
The paper is a report of the work done by Daniel Barlow Lane as a Master of Fine Arts in graduate school. The paper outlines his understanding of what painting is in today’s world as well as his individual work. The paper describes three different series of work in chronological order. Pictures of the work at its different stages are provided for reference along with pictorial references of his major influences throughout his time in graduate school. The paper focuses on the reasons and decisions Daniel has made throughout his time at the University of Texas at Austin and documents in retrospect his understanding of what happened, what he made, and why.Studio Ar
Thermodynamics of de Sitter black holes with a conformally coupled scalar field
We study the thermodynamics of de Sitter black holes with a conformally
coupled scalar field. The geometry is that of the ``lukewarm''
Reissner-Nordstrom-de Sitter black holes, with the event and cosmological
horizons at the same temperature. This means that the region between the event
and cosmological horizons can form a regular Euclidean instanton. The entropy
is modified by the non-minimal coupling of the scalar field to the geometry,
but can still be derived from the Euclidean action, provided suitable
modifications are made to deal with the electrically charged case. We use the
first law as derived from the isolated horizons formalism to compute the local
horizon energies for the event and cosmological horizons.Comment: 9 pages, 2 figures, REVTEX. Minor changes, accepted for publication
in Phys. Rev.
A Variable PV Broad Absorption Line and Quasar Outflow Energetics
Broad absorption lines (BALs) in quasar spectra identify high velocity
outflows that might exist in all quasars and could play a major role in
feedback to galaxy evolution. The viability of BAL outflows as a feedback
mechanism depends on their kinetic energies, as derived from the outflow
velocities, column densities, and distances from the central quasar. We
estimate these quantities for the quasar, Q1413+1143 (redshift ),
aided by the first detection of PV 1118,1128 BAL variability in
a quasar. In particular, PV absorption at velocities where the CIV trough does
not reach zero intensity implies that the CIV BAL is saturated and the absorber
only partially covers the background continuum source (with characteristic size
<0.01 pc). With the assumption of solar abundances, we estimate that the total
column density in the BAL outflow is log N_H > 22.3 (cm^-2). Variability in the
PV and saturated CIV BALs strongly disfavors changes in the ionization as the
cause of the BAL variability, but supports models with high-column density BAL
clouds moving across our lines of sight. The observed variability time of 1.6
yr in the quasar rest frame indicates crossing speeds >750 km/s and a radial
distance from the central black hole of <3.5 pc, if the crossing speeds are
Keplerian. The total outflow mass is ~4100 M_solar, the kinetic energy ~4x10^54
erg, and the ratio of the outflow kinetic energy luminosity to the quasar
bolometric luminosity is ~0.02 (at the minimum column density and maximum
distance), which might be sufficient for important feedback to the quasar's
host galaxy.Comment: 9 pages, 4 figures, accepted for publication in MNRA
Software and methods for oligonucleotide and cDNA array data analysis.
Two HTML-based programs were developed to analyze and filter gene-expression data: 'Bullfrog' for Affymetrix oligonucleotide arrays and 'Spot' for custom cDNA arrays. The programs provide intuitive data-filtering tools through an easy-to-use interface. A background subtraction and normalization program for cDNA arrays was also built that provides an informative summary report with data-quality assessments. These programs are freeware to aid in the analysis of gene-expression results and facilitate the search for genes responsible for interesting biological processes and phenotypes
Burma: Drug Control Progress and Possibilities
Burma is the second largest opium producer in the world, and is quickly becoming a hotbed
of methamphetamine production. Opium profits have helped to finance conflict within
Burma for both the central government and the insurgent ethnic groups; however, with
the 1989 ceasefire agreements with the insurgent ethnic groups the drug control context
changed dramatically. In April 2002, the Kokang and Wa ethnic leaders, whose regions
account for the vast majority of opium poppy cultivation, committed to making their
territory opium-free by 2003 and July 2005 respectively.
The combined drug control efforts of national and local leaders have shown promising
results, as both UN and US opium surveys have confirmed large declines in poppy
cultivation. As Burma continues to reduce opium cultivation, it has struggled in recent
years with an increase in the production of amphetamine-type stimulants (ATS). Combating
the threats from opium and ATS will require different strategies. Stronger border
controls, improved law enforcement and interdiction techniques must complement development
strategies and alternative cropping policies.Myanmar ist der zweitgrößte Opiumproduzent der Welt und hat sich zu einer Hochburg
der Methamphetaminproduktion entwickelt. Die Gewinne aus der Opiumproduktion
halfen sowohl der Zentralregierung als auch den aufständischen ethnischen Gruppen, den
Konflikt zu finanzieren. Seit denWaffenstillstandsvereinbarungen 1989 hat sich der Kontext
der Drogenkontrolle dramatisch verändert. Im April 2002 versprachen die Führer der
Kokang und derWa, in deren Einflussbereich die überwältigende Mehrheit des Mohnanbaus
und der Opiumproduktion stattfindet, ihre Gebiete bis 2003 bzw. 2005 opiumfrei zu
bekommen.
Die vereinten Anstrengungen nationaler und lokaler Führer bei der Bekämpfung der
Drogenproduktion zeigt viel versprechende Ergebnisse; sowohl die Statistiken der UN als
auch der USA bestätigten einen starken Rückgang des Opiumanbaus. Während Burma
den Anbau von Opium reduziert, erlebte es in den vergangenen Jahren einen Anstieg
der Produktion der Amphetamin-Derivate (ATS). Stärkere Grenzkontrollen, verbesserte
Rechtsetzung und Untersuchungstechniken müssen die Entwicklung dieser Strategien
komplementär ergänzen
Variability in Quasar Broad Absorption Line Outflows I. Trends in the Short-Term versus Long-Term Data
Broad absorption lines (BALs) in quasar spectra identify high velocity
outflows that likely exist in all quasars and could play a major role in
feedback to galaxy evolution. The variability of BALs can help us understand
the structure, evolution, and basic physical properties of the outflows. Here
we report on our first results from an ongoing BAL monitoring campaign of a
sample of 24 luminous quasars at redshifts 1.2<z<2.9, focusing on C IV 1549 BAL
variability in two different time intervals: 4 to 9 months (short-term) and 3.8
to 7.7 years (long-term) in the quasar rest-frame. We find that 39% (7/18) of
the quasars varied in the short-term, whereas 65% (15/23) varied in the
long-term, with a larger typical change in strength in the long-term data. The
variability occurs typically in only portions of the BAL troughs. The
components at higher outflow velocities are more likely to vary than those at
lower velocities, and weaker BALs are more likely to vary than stronger BALs.
The fractional change in BAL strength correlates inversely with the strength of
the BAL feature, but does not correlate with the outflow velocity. Both the
short-term and long-term data indicate the same trends. The observed behavior
is most readily understood as a result of the movement of clouds across the
continuum source. If the crossing speeds do not exceed the local Keplerian
velocity, then the observed short-term variations imply that the absorbers are
<6 pc from the central quasar.Comment: 14 pages, 7 figures, accepted for publication in MNRA
A note on the error analysis of classical Gram-Schmidt
An error analysis result is given for classical Gram--Schmidt factorization
of a full rank matrix into where is left orthogonal (has
orthonormal columns) and is upper triangular. The work presented here shows
that the computed satisfies \normal{R}=\normal{A}+E where is an
appropriately small backward error, but only if the diagonals of are
computed in a manner similar to Cholesky factorization of the normal equations
matrix.
A similar result is stated in [Giraud at al, Numer. Math.
101(1):87--100,2005]. However, for that result to hold, the diagonals of
must be computed in the manner recommended in this work.Comment: 12 pages This v2. v1 (from 2006) has not the biliographical reference
set (at all). This is the only modification between v1 and v2. If you want to
quote this paper, please quote the version published in Numerische Mathemati
In the Aural Tradition: Cultural Pedagogies of Black Music
In the context of cultural networks of black Atlantic discourse, this dissertation asks how black music was and is employed for pedagogical purposes. Recognizing that aurality, race, and pedagogy are dynamically involved in the production, reception, and interpretation of culture, the dissertation outlines new directions of inquiry into the aural dimensions and educative functions of African American musical languages. It submits aural tradition as a framework for understanding the ways in which modern African American cultural producers engaged with, intervened in, and regenerated ways of listening that came to mediate popular culture. Moreover, the dissertation conceptualizes African American cultural pedagogy to reveal and constellate a series of cultural pedagogies found within the wide trajectories of African American cultural history. By examining listening alongside African American literature’s epistemological and political investments in recovering diasporic heritage, the undervalued role of listening attains its proper estimation. Hence, the dissertation begins in the early twentieth century when black music came to circulate widely in national and international flows of distribution and reception, and argues that cultural pedagogies coexist as pedagogically reflexive mediations of cultural production in relationship to the sociopolitical dynamics of black diasporicity. The most fundamental relationship between orality and literary production is not writing itself, but the undervalued art and work of listening that effectively enables writing and subsequent learning. By adopting aural tradition as a category of analysis, long-celebrated techniques of literary craft used to represent sound and music are further affirmed as virtuosic constituents of African American literary production; in the shift toward listening, however, such techniques are more fully regarded as efforts to recalibrate, recondition, and newly enhance aurality and teachability
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