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Empirical Estimates and Observations of 0Day Vulnerabilities

Description: We define a 0Day vulnerability to be any vulnerability, in deployed software, that has been discovered by at least one person but has not yet been publicly announced or patched. These 0Day vulnerabilities are of particular interest when assessing the risk to a system from exploit of vulnerabilities which are not generally known to the public or, most importantly, to the owners of the system. Using the 0Day definition given above, we analyzed the 0Day lifespans of 491 vulnerabilities and conserv… more
Date: January 1, 2009
Creator: McQueen, Miles A.; McQueen, Trevor A.; Boyer, Wayne F. & Chaffin, May R.
Partner: UNT Libraries Government Documents Department
open access

Subaru Weak Lensing Measurements of Four Strong Lensing Clusters: Are Lensing Clusters Over-Concentrated?

Description: We derive radial mass profiles of four strong lensing selected clusters which show prominent giant arcs (Abell 1703, SDSS J1446+3032, SDSS J1531+3414, and SDSS J2111-0115), by combining detailed strong lens modeling with weak lensing shear measured from deep Subaru Suprime-cam images. Weak lensing signals are detected at high significance for all four clusters, whose redshifts range from z = 0.28 to 0.64. We demonstrate that adding strong lensing information with known arc redshifts significant… more
Date: January 29, 2009
Creator: Oguri, Masamune; Hennawi, Joseph F.; Gladders, Michael D.; Dahle, Haakon; Natarajan, Priyamvada; Dalal, Neal et al.
Partner: UNT Libraries Government Documents Department
open access

Improving Consistency of Performance Assessments in the Doe Complex

Description: The low-level waste (LLW) performance assessment (PA) process has been traditionally focused on disposal facilities at a few United States Department of Energy (USDOE) sites and commercial disposal facilities. In recent years, there has been a dramatic increase in the scope of the use of PA-like modeling approaches, involving multiple activities, facilities, contractors and regulators. The scope now includes, for example: (1) National Environmental Policy Act (NEPA) assessments, (2) CERCLA disp… more
Date: January 20, 2009
Creator: Seitz, R. & Elmer Wilhite, E.
Partner: UNT Libraries Government Documents Department
open access

Improved Prediction of the Doppler Effect in TRISO Fuel

Description: The Doppler feedback mechanism is a major contributor to the passive safety of gas-cooled, graphite-moderated High Temperature Reactors that use fuel based on TRISO particles. It follows that the correct prediction of the magnitude and time-dependence of this feedback effect is essential to the conduct of safety analyses for these reactors. Since the effect is directly dependent on the actual temperature reached by the fuel during transients, the underlying phenomena of heat transfer and temper… more
Date: May 1, 2009
Creator: Ortensi, J. & Ougouag, A.M.
Partner: UNT Libraries Government Documents Department
open access

DEVELOPMENT OF A CROSSFLOW FILTER TO REMOVE SOLIDS FROM RADIOACTIVE LIQUID WASTE: COMPARISON OF TEST DATA WITH OPERATING EXPERIENCE - 9119

Description: In 2008, the Savannah River Site (SRS) began treatment of liquid radioactive waste from its Tank Farms. To treat waste streams containing {sup 137}Cs, {sup 90}Sr, and actinides, SRS developed the Actinide Removal Process (ARP) and the Modular Caustic Side Solvent Extraction Unit (MCU). The Actinide Removal Process contacts the waste with monosodium titanate (MST) to sorb strontium and select actinides. After MST contact, the process filters the resulting slurry to remove the MST (with sorbed st… more
Date: March 1, 2009
Creator: Poirier, M; David Herman, D; Samuel Fink, S & Julius Lacerna, J
Partner: UNT Libraries Government Documents Department
open access

Precise Predictions for W + 3 Jet Production at Hadron Colliders

Description: We report on the first next-to-leading order QCD computation of W + 3-jet production in hadronic collisions including all partonic subprocesses. We compare the results with CDF data from the Tevatron, and find excellent agreement. The renormalization and factorization scale dependence is reduced substantially compared to leading-order calculations. The required one-loop matrix elements are computed using on-shell methods, implemented in a numerical program, BlackHat. We use the SHERPA package t… more
Date: February 23, 2009
Creator: Berger, C.F.; /MIT, LNS; Bern, Z.; /UCLA; Dixon, L.J.; /SLAC et al.
Partner: UNT Libraries Government Documents Department
open access

Cerocene Revisited: The Electronic Structure of and Interconversion Between Ce2(C8H8)3 and Ce(C8H8)2

Description: New synthetic procedures for the preparation of Ce(cot)2, cerocene, from [Li(thf)4][Ce(cot)2], and Ce2(cot)3 in high yield and purity are reported. Heating solid Ce(cot)2 yields Ce2(cot)3 and COT while heating Ce2(cot)3 with an excess of COT in C6D6 to 65oC over four months yields Ce(cot)2. The solid state magnetic susceptibility of these three organocerium compounds shows that Ce(cot)2 behaves as a TIP (temperature independent paramagnet) over the temperature range of 5-300 K, while that of Ce… more
Date: February 2, 2009
Creator: Walter, Marc D.; Booth, Corwin H.; Lukens, Wayne W. & Andersen, Richard A.
Partner: UNT Libraries Government Documents Department
open access

FUEL CASK IMPACT LIMITER VULNERABILITIES

Description: Cylindrical fuel casks often have impact limiters surrounding just the ends of the cask shaft in a typical 'dumbbell' arrangement. The primary purpose of these impact limiters is to absorb energy to reduce loads on the cask structure during impacts associated with a severe accident. Impact limiters are also credited in many packages with protecting closure seals and maintaining lower peak temperatures during fire events. For this credit to be taken in safety analyses, the impact limiter attachm… more
Date: February 9, 2009
Creator: Leduc, D; Jeffery England, J & Roy Rothermel, R
Partner: UNT Libraries Government Documents Department
open access

Toward a simple molecular understanding of sum frequency generation at air-water interfaces

Description: Second-order vibrational spectroscopies successfully isolate signals from interfaces, but they report on intermolecular structure in a complicated and indirect way. Here we adapt a perspective on vibrational response developed for bulk spectroscopies to explore the microscopic fluctuations to which sum frequency generation (SFG), a popular surface-specific measurement, is most sensitive. We focus exclusively on inhomogeneous broadening of spectral susceptibilities for OH stretching of HOD as a … more
Date: January 13, 2009
Creator: Noah-Vanhoucke, Joyce; Smith, Jared D. & Geissler, Phillip L.
Partner: UNT Libraries Government Documents Department
open access

Enhanced Chemical Cleaning: A New Process for Chemically Cleaning Savannah River Waste Tanks

Description: At the Savannah River Site (SRS) there are 49 High Level Waste (HLW) tanks that eventually must be emptied, cleaned, and closed. The current method of chemically cleaning SRS HLW tanks, commonly referred to as Bulk Oxalic Acid Cleaning (BOAC), requires about a half million liters (130,000 gallons) of 8 weight percent (wt%) oxalic acid to clean a single tank. During the cleaning, the oxalic acid acts as the solvent to digest sludge solids and insoluble salt solids, such that they can be suspende… more
Date: February 11, 2009
Creator: Ketusky, Edward; Spires, Renee & Davis, Neil
Partner: UNT Libraries Government Documents Department
open access

Study of the k+ to pi+, neutrino, anti-neutrino decay in the momentum region p(pi+) < 199 MeV/C

Description: Experiment E949 at Brookhaven National Laboratory has observed three candidate events for the decay K{sup +} {yields} {pi}{sup +}{nu}{bar {nu}} in the pion momentum region 140 &lt; P{sub {pi}} &lt; 199 MeV/c in a exposure of 1.71 x 10{sup 12} stopped kaons with an estimated total background of 0.93 {+-} 0.17(stat.){sub -0.24}{sup +0.32}(syst.) events. Combination of this observation with previous results, assuming a pion spectrum as predicted by the standard model, produces a branching fraction… more
Date: January 1, 2009
Creator: Artamonov, A. V.; Bassalleck, B.; Bhuyan, B.; Blackmore, E. W.; Bryman, D. A.; Chen, S. et al.
Partner: UNT Libraries Government Documents Department
open access

Analysis of an Earthquake-Initiated-Transient in a PBR

Description: One of the Design Basis Accidents (DBA) for a Pebble Bed Reactor has been identified as the “Safe shutdown earthquake with core conduction cooling to passive mode of Reactor Cavity Cooling System.” A new methodology to analyze this particular DBA has been developed at the Idaho National Laboratory (INL). During the seismic event the reactor core experiences the densification of the pebbles, which produce small reactivity insertions due to the effective fuel densification. In addition, a decreas… more
Date: May 1, 2009
Creator: Ougouag, A. M.; Ortensi, J. & Hiruta, H.
Partner: UNT Libraries Government Documents Department
open access

Long-range and head-on beam-beam compensation studies in RHIC with lessons for the LHC

Description: Long-range as well as head-on beam-beam effects are expected to limit the LHC performance with design parameters. They are also important consideration for the LHC upgrades. To mitigate long-range effects, current carrying wires parallel to the beam were proposed. Two such wires are installed in RHIC where they allow studying the effect of strong long-range beam-beam effects, as well as the compensation of a single long-range interaction. The tests provide benchmark data for simulations and ana… more
Date: January 12, 2009
Creator: Fischer, W.; Luo, Y.; Abreu, N.; Calaga, R.; Montag, C.; Robert-Demolaize, G. et al.
Partner: UNT Libraries Government Documents Department
open access

Thermal Analysis for in-Tank Ion-Exchange Column Process

Description: High Level Waste (HLW) at the Savannah River Site (SRS) is stored in three forms: sludge, saltcake, and supernate. A small column ion-exchange (SCIX) process is being designed to treat dissolved saltcake waste before feeding it to the saltstone facility to be made into grout. The waste is caustic with high concentrations of various sodium salts and lower concentrations of radionuclides. Two cation exchange media being considered are a granular form of crystalline silicotitanate (CST) and a sphe… more
Date: January 5, 2009
Creator: Lee, S. & Frank02 Smith, F.
Partner: UNT Libraries Government Documents Department
open access

Physical test of a particle simulation model in a sheared granular system

Description: We report a detailed comparison of a slow gravity driven sheared granular flow with a computational model performed with the Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS). To our knowledge, this is the first thorough test of the LAMMPS model with a laboratory granular flow. In the experiments, grains flow inside a silo with a rectangular cross-section, and are sheared by a rough boundary on one side and smooth boundaries on the other sides. Individual grain position and mot… more
Date: January 15, 2009
Creator: Rycroft, Chris; Orpe, Ashish & Kudrolli, Arshad
Partner: UNT Libraries Government Documents Department
open access

ALUMINUM HYDRIDE: A REVERSIBLE STORAGE MATERIAL FOR HYDROGEN STORAGE

Description: One of the challenges of implementing the hydrogen economy is finding a suitable solid H{sub 2} storage material. Aluminium (alane, AlH{sub 3}) hydride has been examined as a potential hydrogen storage material because of its high weight capacity, low discharge temperature, and volumetric density. Recycling the dehydride material has however precluded AlH{sub 3} from being implemented due to the large pressures required (&gt;10{sup 5} bar H{sub 2} at 25 C) and the thermodynamic expense of chemi… more
Date: January 9, 2009
Creator: Zidan, R; Christopher Fewox, C; Brenda Garcia-Diaz, B & Joshua Gray, J
Partner: UNT Libraries Government Documents Department
open access

Dalitz Plot Analysis of B+- --> pi+-pi+-pi-+ Decays

Description: The authors present a Dalitz-plot analysis of charmless B{sup {+-}} decays to the final state {pi}{sup {+-}}{pi}{sup {+-}}{pi}{sup {-+}} using a sample of (465 {+-} 5) x 10{sup 6} B{bar B} pairs collected by the BABAR experiment at {radical}s = 10.58 GeV. They measure the branching fractions {Beta}(B{sup {+-}} {yields} {pi}{sup {+-}}{pi}{sup {+-}}{pi}{sup {-+}}) = (15.2 {+-} 0.6 {+-} 1.2 {+-} 0.4) x 10{sup -6}, {Beta}(B{sup {+-}} {yields} {rho}{sup 0}(770){pi}{sup {+-}}) = (8.1 {+-} 0.7 {+-} 1.… more
Date: February 23, 2009
Creator: Collaboration, The BABAR & Aubert, B.
Partner: UNT Libraries Government Documents Department
open access

Discontinuous Galerkin solution of the Navier-Stokes equations on deformable domains

Description: We describe a method for computing time-dependent solutions to the compressible Navier-Stokes equations on variable geometries. We introduce a continuous mapping between a fixed reference configuration and the time varying domain, By writing the Navier-Stokes equations as a conservation law for the independent variables in the reference configuration, the complexity introduced by variable geometry is reduced to solving a transformed conservation law in a fixed reference configuration, The spati… more
Date: January 13, 2009
Creator: Persson, P.-O.; Bonet, J. & Peraire, J.
Partner: UNT Libraries Government Documents Department
open access

How did matter gain the upper hand over antimatter?

Description: Antimatter exists! We routinely make it in laboratories. For every familiar particle type we find a matching antiparticle with opposite charge, but exactly the same mass. For example, a positron with positive charge has the same mass as an electron; an antiproton with negative charge has the same mass as a proton. Antimatter occurs naturally all over the universe wherever high-energy particles collide. The laws of physics for antimatter are very, very similar to those for antimatter--so far we … more
Date: January 30, 2009
Creator: Quinn, Helen
Partner: UNT Libraries Government Documents Department
open access

Search for the Z(4430) at BABAR

Description: We report the results of a search for Z(4430){sup -} decay to J/{psi}{pi}{sup -} or {psi}(2S){pi}{sup -} in B{sup -,0} {yields} J/{psi}{pi}{sup -} K{sup 0,+} and B{sup -,0} {yields} {psi}(2S){pi}{sup -}K{sup 0,+} decays. The data were collected with the BABAR detector at the SLAC PEP-II asymmetric-energy e{sup +}e{sup -} collider operating at center of mass energy 10.58 GeV, and the sample corresponds to an integrated luminosity of 413 fb{sup -1}. Each K{pi}{sup -} mass distribution exhibits cl… more
Date: January 12, 2009
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department
open access

Direct Measurement of the W Production Charge Asymmetry in p anti-p Collisions at s**(1/2) = 1.96-TeV

Description: We present the first direct measurement of the W production charge asymmetry as a function of the W boson rapidity y{sub W} in p{bar p} collisions at {radical}s = 1.96 TeV. We use a sample of W {yields} e{nu} events in data from 1 fb{sup -1} of integrated luminosity collected using the CDF II detector. In the region |y{sub W}| &lt; 3.0, this measurement is capable of constraining the ratio of up and down quark momentum distributions in the proton more directly than in previous measurements of t… more
Date: January 1, 2009
Creator: Aaltonen, T.; Phys., /Helsinki Inst. of; Adelman, J.; /Chicago U., EFI; Akimoto, T.; U., /Tsukuba et al.
Partner: UNT Libraries Government Documents Department
open access

Meshless Solution of the Vlasov Equation Using a Low Discrepancy Sequence

Description: A good method for solving the nonlinear Vlasov equation is the semi-Lagrangian algorithm, in which the phase space density is represented by its values on a fixed Cartesian grid with interpolation to off-grid points. At each time step, orbits are followed backward from grid points. Since this method is expensive with phase space dimension D &gt; 2, we seek a more efficient discretization of the density. Taking a cue from the theory of numerical quadrature in high dimensions, we explore the idea… more
Date: January 28, 2009
Creator: Warnock, R. L.; Ellison, J. A.; Heinemann, K. & Zhang, G. Q.
Partner: UNT Libraries Government Documents Department
open access

TTF HOM Data Analysis with Curve Fitting Method

Description: To investigate the possibility of using HOM signals induced in SC cavities as beam and cavity diagnostics, narrow band (20 MHz) data was recorded around the strong TE111-6(6{pi}/9-like) dipole modes (1.7 GHz) in the 40 L-band (1.3 GHz) cavities at the DESY TTF facility. The analyses of these data have so far focused on using a Singular Value Decomposition (SVD) technique to correlate the signals with each other and data from conventional BPMs to show the dipole signals provide an alternate mean… more
Date: July 14, 2009
Creator: Pei, S.; Adolphsen, C.; Li, Z.; Bane, K. & Smith, J.
Partner: UNT Libraries Government Documents Department
open access

Sensor Development and Readout Prototyping for the STAR Pixel Detector

Description: The STAR experiment at the Relativistic Heavy Ion Collider (RHIC) is designing a new vertex detector. The purpose of this upgrade detector is to provide high resolution pointing to allow for the direct topological reconstruction of heavy flavor decays such as the D{sup 0} by finding vertices displaced from the collision vertex by greater than 60 microns. We are using Monolithic Active Pixel Sensor (MAPS) as the sensor technology and have a coupled sensor development and readout system plan that… more
Date: January 14, 2009
Creator: Greiner, L.; Anderssen, E.; Matis, H. S.; Ritter, H. G.; Stezelberger, T.; Szelezniak, M. et al.
Partner: UNT Libraries Government Documents Department
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