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Troubled Asset Relief Program: Additional Actions Needed to Better Ensure Integrity, Accountability, and Transparency

Description: Testimony issued by the Government Accountability Office with an abstract that begins "This testimony discusses our first report on the newly created Troubled Asset Relief Program (TARP), which gave the Department of Treasury the authority to purchase and insure up to $700 billion in troubled assets held by financial institutions through the Office of Financial Stability (OFS). Treasury was granted this authority in response to the recent financial crisis that has threatened the stability of th… more
Date: December 10, 2008
Creator: United States. Government Accountability Office.
Item Type: Refine your search to only Text
Partner: UNT Libraries Government Documents Department
open access

BDDC for nonsymmetric positive definite and symmetric indefinite problems

Description: The balancing domain decomposition methods by constraints are extended to solving both nonsymmetric, positive definite and symmetric, indefinite linear systems. In both cases, certain nonstandard primal constraints are included in the coarse problems of BDDC algorithms to accelerate the convergence. Under the assumption that the subdomain size is small enough, a convergence rate estimate for the GMRES iteration is established that the rate is independent of the number of subdomains and depends … more
Date: December 10, 2008
Creator: Tu, Xuemin & Li, Jing
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Practical error estimates for Reynolds' lubrication approximation and its higher order corrections

Description: Reynolds lubrication approximation is used extensively to study flows between moving machine parts, in narrow channels, and in thin films. The solution of Reynolds equation may be thought of as the zeroth order term in an expansion of the solution of the Stokes equations in powers of the aspect ratio {var_epsilon} of the domain. In this paper, we show how to compute the terms in this expansion to arbitrary order on a two-dimensional, x-periodic domain and derive rigorous, a-priori error bounds … more
Date: December 10, 2008
Creator: Wilkening, Jon
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

QCD Evolution of the Transverse Momentum Dependent Correlations

Description: We study the QCD evolution for the twist-three quark-gluon correlation functions associated with the transverse momentum odd quark distributions. Different from that for the leading twist quark distributions, these evolution equations involve more general twist-three functions beyond the correlation functions themselves. They provide important information on nucleon structure, and can be studied in the semi-inclusive hadron production in deep inelastic scattering and Drell-Yan lepton pair produ… more
Date: December 10, 2008
Creator: Zhou, Jian; Liang, Zuo-Tang & Yuan, Feng
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Semi-inclusive DIS: Factorization

Description: In this talk, we will present a QCD factorization theorem for the semi-inclusive deep-inelastic scattering with hadrons in the current fragmentation region detected at low transverse momentum. There has been considerable experimental and theoretical interest in semi-inclusive hadron production in deep inelastic scattering (SIDIS) processes. For example, by studying the polarized and unpolarized SIDIS, one will be able to identify the sea quark distribution and polarization in nucleon, and the e… more
Date: December 10, 2008
Creator: Yuan, Feng
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Shape optimization of a sheet swimming over a thin liquid layer

Description: Motivated by the propulsion mechanisms adopted by gastropods, annelids and other invertebrates, we consider shape optimization of a flexible sheet that moves by propagating deformation waves along its body. The self-propelled sheet is separated from a rigid substrate by a thin layer of viscous Newtonian fluid. We use a lubrication approximation to model the dynamics and derive the relevant Euler-Lagrange equations to simultaneously optimize swimming speed, efficiency and fluid loss. We find tha… more
Date: December 10, 2008
Creator: Wilkening, J. & Hosoi, A.E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

A balancing domain decomposition method by constraints for advection-diffusion problems

Description: The balancing domain decomposition methods by constraints are extended to solving nonsymmetric, positive definite linear systems resulting from the finite element discretization of advection-diffusion equations. A pre-conditioned GMRES iteration is used to solve a Schur complement system of equations for the subdomain interface variables. In the preconditioning step of each iteration, a partially sub-assembled finite element problem is solved. A convergence rate estimate for the GMRES iteration… more
Date: December 10, 2008
Creator: Tu, Xuemin & Li, Jing
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Recent Development in Proton Spin Physics

Description: In the naive model of the proton, its 1/2 spin is carried by its quark constituents. However, experiments over the last several decades have shown that the quark spin only contribute a small portion of the proton spin. In this talk, I will present recent developments exploring this proton spin puzzle, and focus on the progress made in the last few years on the longitudinal spin physics, the generalized parton distribution physics, and the transverse spin physics.
Date: December 10, 2008
Creator: Yuan, Feng
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Variational particle scheme for the porous medium equation and for the system of isentropic Euler equations

Description: We introduce variational particle schemes for the porous medium equation and the system of isentropic Euler equations in one space dimension. The methods are motivated by the interpretation of each of these partial differential equations as a 'steepest descent' on a suitable abstract manifold. We show that our methods capture very well the nonlinear features of the flows.
Date: December 10, 2008
Creator: Westdickenberg, Michael & Wilkening, Jon
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

A Three-level BDDC algorithm for saddle point problems

Description: BDDC algorithms have previously been extended to the saddle point problems arising from mixed formulations of elliptic and incompressible Stokes problems. In these two-level BDDC algorithms, all iterates are required to be in a benign space, a subspace in which the preconditioned operators are positive definite. This requirement can lead to large coarse problems, which have to be generated and factored by a direct solver at the beginning of the computation and they can ultimately become a bottl… more
Date: December 10, 2008
Creator: Tu, X.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Development of ZnO:Ga as an Ultrafast Scintillator

Description: We report on several methods for synthesizing the ultra-fast scintillator ZnO(Ga), and measurements of the resulting products. This material has characteristics that make it an excellent alpha detector for tagging the time and direction of individual neutrons produced by t-d and d-d neutron generators (associated particle imaging). The intensity and decay time are strongly dependent on the method used for dopant incorporation. We compare samples made by diffusion of Ga metal to samples made by … more
Date: December 10, 2008
Creator: Bourret-Courchesne, E. D.; Derenzo, S. E. & Weber, M. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Inf-sup estimates for the Stokes problem in a periodic channel

Description: We derive estimates of the Babuska-Brezzi inf-sup constant {beta} for two-dimensional incompressible flow in a periodic channel with one flat boundary and the other given by a periodic, Lipschitz continuous function h. If h is a constant function (so the domain is rectangular), we show that periodicity in one direction but not the other leads to an interesting connection between {beta} and the unitary operator mapping the Fourier sine coefficients of a function to its Fourier cosine coefficient… more
Date: December 10, 2008
Creator: Wilkening, Jon
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Two-phase viscoelastic jetting

Description: A coupled finite difference algorithm on rectangular grids is developed for viscoelastic ink ejection simulations. The ink is modeled by the Oldroyd-B viscoelastic fluid model. The coupled algorithm seamlessly incorporates several things: (1) a coupled level set-projection method for incompressible immiscible two-phase fluid flows; (2) a higher-order Godunov type algorithm for the convection terms in the momentum and level set equations; (3) a simple first-order upwind algorithm for the convect… more
Date: December 10, 2008
Creator: Yu, J.-D.; Sakai, S. & Sethian, J. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Transverse Spin Physics: Recent Developments

Description: Transverse-spin physics has been very active and rapidly developing in the last few years. In this talk, I will briefly summarize recent theoretical developments, focusing on the associated QCD dynamics in transverse spin physics.
Date: December 10, 2008
Creator: Yuan, Feng
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Convergence analysis of a balalncing domain decomposition method for solving interior Helmholtz equations

Description: A variant of balancing domain decomposition method by constraints (BDDC) is proposed for solving a class of indefinite system of linear equations, which arises from the finite element discretization of the Helmholtz equation of time-harmonic wave propagation in a bounded interior domain. The proposed BDDC algorithm is closely related to the dual-primal finite element tearing and interconnecting algorithm for solving Helmholtz equations (FETI-DPH). Under the condition that the diameters of the s… more
Date: December 10, 2008
Creator: Li,Jing & Tu, Xuemin
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Couse/Tenmile Creeks Watershed Project Implementation : 2007 Conservtion Projects. [2007 Habitat Projects Completed].

Description: The Asotin County Conservation District (ACCD) is the primary entity coordinating habitat projects on private lands within Asotin County watersheds. The Tenmile Creek watershed is a 42 square mile tributary to the Snake River, located between Asotin Creek and the Grande Ronde River. Couse Creek watershed is a 24 square mile tributary to the Snake River, located between Tenmile Creek and the Grande Ronde River. Both watersheds are almost exclusively under private ownership. The Washington Depart… more
Date: December 10, 2008
Creator: District, Asotin County Conservation
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Complexation of Lanthanides with Nitrate at Variable Temperatures: Thermodynamics and Coordination Modes

Description: Complexation of neodymium(III) with nitrate was studied at variable temperatures (25, 40, 55 and 70 C) by spectrophotometry and microcalorimetry. The NdNO{sub 3}{sup 2+} complex is weak and becomes slightly stronger as the temperature is increased. The enthalpy of complexation at 25 C was determined by microcalorimetry to be small and positive, (1.5 {+-} 0.2) kJ {center_dot} mol{sup -1}, in good agreement with the trend of the stability constant at variable temperatures. Luminescence emission s… more
Date: December 10, 2008
Creator: Rao, Linfeng & Tian, Guoxin
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Measurements of NaI(Tl) electron response: comparison of different samples

Description: This paper measures the sample to sample variation in the light yield proportionality of NaI(Tl), and so explores whether this is an invariant characteristic of the material or whether it depends on the chemical and physical properties of the tested samples. We report on the electron response of nine crystals of NaI(Tl), differing in shape, volume, age, manufacturer and quality. The proportionality has been measured at the SLYNCI facility in the energy range between 3.5 to 460 keV. We observe t… more
Date: December 10, 2008
Creator: Hull, Giulia; Choong, Woon-Seng; Moses, William W.; Bizarri, Gregory; Valentine, John D.; Payne, Stephen A. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Disturbance of isotope systematics in meteorites during shock and thermal metamorphism and implications for shergottite chronology

Description: Shock and thermal metamorphism of meteorites from differentiated bodies such as the Moon and Mars have the potential to disturb chronometric information contained in these meteorites. In order to understand the impact-related mechanisms and extent of disturbance to isochrons, we undertook experiments to shock and heat samples of 10017, a 3.6 billion year old lunar basalt. One sub-sample was shocked to 55 GPa, a second subsample was heated to 1000 C for one week, and a third sub-sample was maint… more
Date: December 10, 2008
Creator: Gaffney, Amy M.; Borg, Lars E. & Asmerom, Yemane
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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