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Small Wind Turbine Testing Results from the National Renewable Energy Laboratory: Preprint

Description: In 2008, the U.S. Department of Energy's (DOE) National Renewable Energy Laboratory (NREL) began testing small wind turbines (SWTs) through the Independent Testing project. Using competitive solicitation, five SWTs were selected for testing at the National Wind Technology Center (NWTC). NREL's NWTC is accredited by the American Association of Laboratory Accreditation (A2LA) to conduct duration, power performance, safety and function, power quality, and noise tests to International Electrotechni… more
Date: April 1, 2010
Creator: Bowen, A.; Huskey, A.; Link, H.; Sinclair, K.; Forsyth, T.; Jager, D. et al.
Partner: UNT Libraries Government Documents Department
open access

Direct-Drive Inertial Fusion Research at the University of Rochester's Laboratory for Laser Energetics: A Review

Description: This paper reviews the status of direct-drive inertial confinement fusion (ICF) research at the University of Rochester's Laboratory for Laser Energetics (LLE). LLE's goal is to demonstrate direct-drive ignition on the National Ignition Facility (NIF) by 2014. Baseline "all-DT" NIF direct-drive ignition target designs have been developed that have a predicted gain of 45 (1-D) at a NIF drive energy of ~1.6 MJ. Significantly higher gains are calculated for targets that include a DT-wicked foam ab… more
Date: April 16, 2010
Creator: McCrory, R. L.; Meyerhofer, D. D.; Loucks, S. J.; Skupsky, S.; Bahr, R. E.; Betti, R. et al.
Partner: UNT Libraries Government Documents Department
open access

Training new operators - the first six months

Description: The Fermilab Operations Department takes about two years to train a new Operator. The Operator's introductory (Concepts) On-the-Job-Training (OJT) gives him or her an overview of the laboratory, teaches the basic facts about all the accelerators, and it also teaches the new operator the training process used for all the rest of their OJT training. The Concepts OJT takes about four to six months for most people to complete. This paper will explain how this first six months of training sets the n… more
Date: April 1, 2010
Creator: Worthel, B.
Partner: UNT Libraries Government Documents Department
open access

Radiation Protection Studies for LCLS Tune Up Dump

Description: The Linac Coherent Light Source (LCLS) at the Stanford Linear Accelerator Center is a pioneer fourth generation hard x-ray free electron laser that shall start to deliver laser pulses in 2009. Among other components of LCLS that present radiation protection concerns, the tune up dump (tdund) is of special interest because it also constitutes an issue for machine protection, as it is placed close to radiation sensitive components, like electronic devices and permanent magnets in the undulators. … more
Date: April 29, 2010
Creator: Santana-Leitner, M.; Fass, A.; Mao, S.; Nuhn, H. D.; Roesler, S.; Rokni, S. et al.
Partner: UNT Libraries Government Documents Department
open access

Quantum Detection and Invisibility in Coherent Nanostructures

Description: We address quantum invisibility in the context of electronics in nanoscale quantum structures. In analogy with metamaterials, we use the freedom of design that quantum corrals provide and show that quantum mechanical objects can be hidden inside the corral, with respect to inelastic electron scattering spectroscopy in combination with scanning tunneling microscopy, and we propose a design strategy. A simple illustration of the invisibility is given in terms of an elliptic quantum corral contain… more
Date: April 28, 2010
Creator: Fransson, J.
Partner: UNT Libraries Government Documents Department
open access

Meson spectroscopy at the Tevatron

Description: The Tevatron experiments have each accumulated about 6 fb{sup -1} good data since the start of RUN II. This large dataset provided good opportunities for meson spectroscopy studies at the Tevatron. This article will cover the recent new {Upsilon}(nS) polarization studies as well as exotic meson spectroscopy studies.
Date: April 1, 2010
Creator: Yi, Kai
Partner: UNT Libraries Government Documents Department
open access

Non-diffusive spin dynamics in a two-dimensional electron gas

Description: We describe measurements of spin dynamics in the two-dimensional electron gas in GaAs/GaAlAs quantum wells. Optical techniques, including transient spin-grating spectroscopy, are used to probe the relaxation rates of spin polarization waves in the wavevector range from zero to 6 x 10{sup 4} cm{sup -1}. We find that the spin polarization lifetime is maximal at nonzero wavevector, in contrast with expectation based on ordinary spin diffusion, but in quantitative agreement with recent theories tha… more
Date: April 28, 2010
Creator: Weber, C.P.
Partner: UNT Libraries Government Documents Department
open access

Modular Countermine Payload for Small Robots

Description: Payloads for small robotic platforms have historically been designed and implemented as platform and task specific solutions. A consequence of this approach is that payloads cannot be deployed on different robotic platforms without substantial re-engineering efforts. To address this issue, we developed a modular countermine payload that is designed from the ground-up to be platform agnostic. The payload consists of the multi-mission payload controller unit (PCU) coupled with the configurable mi… more
Date: April 1, 2010
Creator: Herman, Herman; Few, Doug; Versteeg, Roelof; Valois, Jean-Sebastien; McMahill, Jeff; Licitra, Michael et al.
Partner: UNT Libraries Government Documents Department
open access

Angle-Resolved Photoemission Spectroscopy on Electronic Structure and Electron-Phonon Coupling in Cuprate Superconductors

Description: In addition to the record high superconducting transition temperature (T{sub c}), high temperature cuprate superconductors are characterized by their unusual superconducting properties below T{sub c}, and anomalous normal state properties above T{sub c}. In the superconducting state, although it has long been realized that superconductivity still involves Cooper pairs, as in the traditional BCS theory, the experimentally determined d-wave pairing is different from the usual s-wave pairing found… more
Date: April 30, 2010
Creator: Zhou, X.J.
Partner: UNT Libraries Government Documents Department
open access

Single-Atom Gating of Quantum State Superpositions

Description: The ultimate miniaturization of electronic devices will likely require local and coherent control of single electronic wavefunctions. Wavefunctions exist within both physical real space and an abstract state space with a simple geometric interpretation: this state space - or Hilbert space - is spanned by mutually orthogonal state vectors corresponding to the quantized degrees of freedom of the real-space system. Measurement of superpositions is akin to accessing the direction of a vector in Hil… more
Date: April 28, 2010
Creator: Moon, Christopher
Partner: UNT Libraries Government Documents Department
open access

A momentum-dependent perspective on quasiparticleinterference in Bi2Sr2CaCu2O_8+delta

Description: Angle Resolved Photoemission Spectroscopy (ARPES) probes the momentum-space electronic structure of materials, and provides invaluable information about the high-temperature superconducting cuprates. Likewise, cuprates real-space, inhomogeneous electronic structure is elucidated by Scanning Tunneling Spectroscopy (STS). Recently, STS has exploited quasiparticle interference (QPI) - wave-like electrons scattering off impurities to produce periodic interference patterns - to infer properties of t… more
Date: April 29, 2010
Creator: Vishik, I. M.
Partner: UNT Libraries Government Documents Department
open access

Observation of Single Top Quark Production and Measurement of |Vtb| with CDF

Description: We report the observation of electroweak single top quark production in 3.2 fb{sup -1} of p{bar p} collision data collected by the Collider Detector at Fermilab at {radical}s = 1.96 TeV. Candidate events in the W+jets topology with a leptonically decaying W boson are classified as signal-like by four parallel analyses based on likelihood functions, matrix elements, neural networks, and boosted decision trees. These results are combined using a super discriminant analysis based on genetically ev… more
Date: April 1, 2010
Creator: Aaltonen, T.; Adelman, J.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, D.; Anastassov, A. et al.
Partner: UNT Libraries Government Documents Department
open access

Evidence for weak electronic correlations in Fe-pnictides

Description: Using x-ray absorption and resonant inelastic x-ray scattering, charge dynamics at and near the Fe L edges is investigated in Fe pnictide materials, and contrasted to that measured in other Fe compounds. It is shown that the XAS and RIXS spectra for 122 and 1111 Fe pnictides are each qualitatively similar to Fe metal. Cluster diagonalization, multiplet, and density-functional calculations show that Coulomb correlations are much smaller than in the cuprates, highlighting the role of Fe metallici… more
Date: April 29, 2010
Creator: Yang, W.L.
Partner: UNT Libraries Government Documents Department
open access

DEVELOPMENT OF ASME SECTION X CODE RULES FOR HIGH PRESSURE COMPOSITE HYDROGEN PRESSURE VESSELS WITH NON-LOAD SHARING LINERS

Description: The Boiler and Pressure Vessel Project Team on Hydrogen Tanks was formed in 2004 to develop Code rules to address the various needs that had been identified for the design and construction of up to 15000 psi hydrogen storage vessel. One of these needs was the development of Code rules for high pressure composite vessels with non-load sharing liners for stationary applications. In 2009, ASME approved new Appendix 8, for Section X Code which contains the rules for these vessels. These vessels are… more
Date: April 13, 2010
Creator: Rawls, G.; Newhouse, N.; Rana, M.; Shelley, B. & Gorman, M.
Partner: UNT Libraries Government Documents Department
open access

Challenges of Algebraic Multigrid across Multicore Architectures

Description: Algebraic multigrid (AMG) is a popular solver for large-scale scientific computing and an essential component of many simulation codes. AMG has shown to be extremely efficient on distributed-memory architectures. However, when executed on modern multicore architectures, we face new challenges that can significantly deteriorate AMG's performance. We examine its performance and scalability on three disparate multicore architectures: a cluster with four AMD Opteron Quad-core processors per node (H… more
Date: April 12, 2010
Creator: Baker, A H; Gamblin, T; Schulz, M & Yang, U M
Partner: UNT Libraries Government Documents Department
open access

Recent results in DIS from Jefferson Lab

Description: Recent results in Deep Inelastic processes measured at Jefferson Lab are presented. In addition to the inclusive reactions typically discussed in the context of Deep Inelastic (electron) Scattering, particular emphasis is given to Deep Exclusive and semi#19;inclusive reactions. Jefferson Lab has made significant contributions to the understanding of the partonic structure of the nucleon at large x, and with its first dedicated measurements is already providing important contributions to underst… more
Date: April 1, 2010
Creator: Gaskell, David
Partner: UNT Libraries Government Documents Department
open access

GenePRIMP: A GENE PRediction IMprovement Pipeline for Prokaryotic genomes

Description: We present 'gene prediction improvement pipeline' (GenePRIMP; http://geneprimp.jgi-psf.org/), a computational process that performs evidence-based evaluation of gene models in prokaryotic genomes and reports anomalies including inconsistent start sites, missed genes and split genes. We found that manual curation of gene models using the anomaly reports generated by GenePRIMP improved their quality, and demonstrate the applicability of GenePRIMP in improving finishing quality and comparing diffe… more
Date: April 1, 2010
Creator: Pati, Amrita; Ivanova, Natalia N.; Mikhailova, Natalia; Ovchinnikova, Galina; Hooper, Sean D.; Lykidis, Athanasios et al.
Partner: UNT Libraries Government Documents Department
open access

High Pressure - High Temperature Polymorphism in Ta: Resolving an Ongoing Experimental Controversy

Description: Phase diagrams of refractory metals remain essentially unknown. Moreover, there is an ongoing controversy over the high pressure (P) melting temperatures of these metals: results of diamond anvil cell (DAC) and shock wave experiments differ by at least a factor of two. From an extensive ab initio study on tantalum we discovered that the body-centered cubic phase, its physical phase at ambient conditions, transforms to another solid phase, possibly hexagonal omega phase, at high temperature (T).… more
Date: April 7, 2010
Creator: Burkovsky, L.; Chen, S. P.; Preston, D. L.; Belonoshko, A. B.; Rosengren, A.; Mikhaylushkin, A. S. et al.
Partner: UNT Libraries Government Documents Department
open access

Simple Fully Automated Group Classification on Brain fMRI

Description: We propose a simple, well grounded classification technique which is suited for group classification on brain fMRI data sets that have high dimensionality, small number of subjects, high noise level, high subject variability, imperfect registration and capture subtle cognitive effects. We propose threshold-split region as a new feature selection method and majority voteas the classification technique. Our method does not require a predefined set of regions of interest. We use average acros sses… more
Date: April 14, 2010
Creator: Honorio, J.; Goldstein, R.; Honorio, J.; Samaras, D.; Tomasi, D. & Goldstein, R.Z.
Partner: UNT Libraries Government Documents Department
open access

The Influence of Linker Geometry on Uranyl Complexation by Rigidly-Linked Bis(3-hydroxy-N-methyl-pyridin-2-one)

Description: A series of bis(3-hydroxy-N-methyl-pyridin-2-one) ligands was synthesized, and their respective uranyl complexes were characterized by single crystal X-ray diffraction analyses. These structures were inspected for high-energy conformations and evaluated using a series of metrics to measure co-planarity of chelating moieties with each other and the uranyl coordination plane, as well as to measure coordinative crowding about the uranyl dication. Both very short (ethyl, 3,4-thiophene and o-phenyle… more
Date: April 22, 2010
Creator: Szigethy, Geza & Raymond, Kenneth
Partner: UNT Libraries Government Documents Department
open access

A Multi-Dimensional Classification Model for Scientific Workflow Characteristics

Description: Workflows have been used to model repeatable tasks or operations in manufacturing, business process, and software. In recent years, workflows are increasingly used for orchestration of science discovery tasks that use distributed resources and web services environments through resource models such as grid and cloud computing. Workflows have disparate re uirements and constraints that affects how they might be managed in distributed environments. In this paper, we present a multi-dimensional cla… more
Date: April 5, 2010
Creator: Ramakrishnan, Lavanya & Plale, Beth
Partner: UNT Libraries Government Documents Department
open access

Epithermal Neutron Source for Neutron Resonance Spectroscopy (NRS) using High Intensity, Short Pulse Lasers

Description: A neutron source for neutron resonance spectroscopy (NRS) has been developed using high intensity, short pulse lasers. This measurement technique will allow for robust measurements of interior ion temperature of laser-shocked materials and provide insight into equation of state (EOS) measurements. The neutron generation technique uses protons accelerated by lasers off of Cu foils to create neutrons in LiF, through (p,n) reactions with {sup 7}Li and {sup 19}F. The distribution of the incident pr… more
Date: April 22, 2010
Creator: Higginson, D. P.; McNaney, J. M.; Swift, D. C.; Bartal, T.; Hey, D. S.; Pape, S. L. et al.
Partner: UNT Libraries Government Documents Department
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