Numerical Calculation of Neoclassical Distribution Functions and Current Profiles in Low Collisionality, Axisymmetric Plasmas (open access)

Numerical Calculation of Neoclassical Distribution Functions and Current Profiles in Low Collisionality, Axisymmetric Plasmas

A new code, the Neoclassical Ion-Electron Solver (NIES), has been written to solve for stationary, axisymmetric distribution functions (f ) in the conventional banana regime for both ions and elec trons using a set of drift-kinetic equations (DKEs) with linearized Fokker-Planck-Landau collision operators. Solvability conditions on the DKEs determine the relevant non-adiabatic pieces of f (called h ). We work in a 4D phase space in which Ψ defines a flux surface, θ is the poloidal angle, v is the total velocity referenced to the mean flow velocity, and λ is the dimensionless magnetic moment parameter. We expand h in finite elements in both v and λ#21; . The Rosenbluth potentials, φ#8; and ψ, which define the integral part of the collision operator, are expanded in Legendre series in cos χ , where #31;χ is the pitch angle, Fourier series in cos #18;θ , and finite elements in v . At each ψ , we solve a block tridiagonal system for hi (independent of fe ), then solve another block tridiagonal system for he (dependent on fi ). We demonstrate that such a formulation can be accurately and efficiently solved. NIES is coupled to the MHD equilibrium code JSOLVER [J. …
Date: June 28, 2012
Creator: B.C. Lyons, S.C. Jardin, and J.J. Ramos
Object Type: Report
System: The UNT Digital Library
High Performance Computing Productivity Study - Evaluation of Parallel Tools Platform (PTP) Eclipse Plug-In (open access)

High Performance Computing Productivity Study - Evaluation of Parallel Tools Platform (PTP) Eclipse Plug-In

None
Date: June 28, 2012
Creator: Banks, Lawrence E. & Dube, Eveline I.
Object Type: Report
System: The UNT Digital Library
Community Development Block Grants: Funding Issues in the 112th Congress and Recent Funding History (open access)

Community Development Block Grants: Funding Issues in the 112th Congress and Recent Funding History

This report discusses funding Issues in the 112th Congress and Recent Funding History The Administration's FY2012 budget proposes to: (1) increase funding for CDBG formula grants by 10.5% from $3.303 billion appropriated in FY2010 to $3.691 billion; (2) eliminate funding for the Neighborhood Initiative and Economic Development Initiative programs; (3) eliminate funding for Section 107 activities; (4) transfer its Sustainable Communities Initiative to a new stand-alone account; and (5) convert Section 108 loan guarantees to a fee-based program.
Date: June 28, 2012
Creator: Boyd, Eugene
Object Type: Report
System: The UNT Digital Library
Development of a mid-sized Schwarzschild-Couder Telescope for the Cherenkov Telescope Array (open access)

Development of a mid-sized Schwarzschild-Couder Telescope for the Cherenkov Telescope Array

The Cherenkov Telescope Array (CTA) is a ground-based observatory for very high-energy (10 GeV to 100 TeV) gamma rays, planned for operation starting in 2018. It will be an array of dozens of optical telescopes, known as Atmospheric Cherenkov Telescopes (ACTs), of 8 m to 24 m diameter, deployed over an area of more than 1 square km, to detect flashes of Cherenkov light from showers initiated in the Earth's atmosphere by gamma rays. CTA will have improved angular resolution, a wider energy range, larger fields of view and an order of magnitude improvement in sensitivity over current ACT arrays such as H.E.S.S., MAGIC and VERITAS. Several institutions have proposed a research and development program to eventually contribute 36 medium-sized telescopes (9 m to 12 m diameter) to CTA to enhance and optimize its science performance. The program aims to construct a prototype of an innovative, Schwarzschild-Couder telescope (SCT) design that will allow much smaller and less expensive cameras and much larger fields of view than conventional Davies-Cotton designs, and will also include design and testing of camera electronics for the necessary advances in performance, reliability and cost. We report on the progress of the mid-sized SCT development program.
Date: June 28, 2012
Creator: Cameron, Robert A.
Object Type: Article
System: The UNT Digital Library
Fermi Large Area Telescope Operations: Progress Over 4 Years (open access)

Fermi Large Area Telescope Operations: Progress Over 4 Years

The Fermi Gamma-ray Space Telescope was launched into orbit in June 2008, and is conducting a multi-year gamma-ray all-sky survey, using the main instrument on Fermi, the Large Area Telescope (LAT). Fermi began its science mission in August 2008, and has now been operating for almost 4 years. The SLAC National Accelerator Laboratory hosts the LAT Instrument Science Operations Center (ISOC), which supports the operation of the LAT in conjunction with the Mission Operations Center (MOC) and the Fermi Science Support Center (FSSC), both at NASA's Goddard Space Flight Center. The LAT has a continuous output data rate of about 1.5 Mbits per second, and data from the LAT are stored on Fermi and transmitted to the ground through TDRS and the MOC to the ISOC about 10 times per day. Several hundred computers at SLAC are used to process LAT data to perform event reconstruction, and gamma-ray photon data are subsequently delivered to the FSSC for public release with a few hours of being detected by the LAT. We summarize the current status of the LAT, and the evolution of the data processing and monitoring performed by the ISOC during the first 4 years of the Fermi mission, together …
Date: June 28, 2012
Creator: Cameron, Robert A.
Object Type: Article
System: The UNT Digital Library
Adaptive Wavenumber Estimation for Mode Tracking in a Shallow Ocean Environment (open access)

Adaptive Wavenumber Estimation for Mode Tracking in a Shallow Ocean Environment

None
Date: June 28, 2012
Creator: Candy, J V
Object Type: Article
System: The UNT Digital Library
Service Oriented Architecture for High Level Applications (open access)

Service Oriented Architecture for High Level Applications

Standalone high level applications often suffer from poor performance and reliability due to lengthy initialization, heavy computation and rapid graphical update. Service-oriented architecture (SOA) is trying to separate the initialization and computation from applications and to distribute such work to various service providers. Heavy computation such as beam tracking will be done periodically on a dedicated server and data will be available to client applications at all time. Industrial standard service architecture can help to improve the performance, reliability and maintainability of the service. Robustness will also be improved by reducing the complexity of individual client applications.
Date: June 28, 2012
Creator: Chu, Chungming; Chevtsov, Sergei; Wu, Juhao & Shen, Guobao
Object Type: Article
System: The UNT Digital Library
Varying the Pre-discharge Lithium Wall Coatings to Alter the Characteristics of the ELM-free H-mode Pedestal in NSTX (open access)

Varying the Pre-discharge Lithium Wall Coatings to Alter the Characteristics of the ELM-free H-mode Pedestal in NSTX

A previous experiment in the National Spherical Torus Experiment (NSTX) showed pre-discharge lithium deposition gradually suppresed edge-localized modes (ELMs) and had nearly continuous relationships with reduced recycling and transport. In this paper, additional data filled gaps in the earlier experiment, and demonstrates that recycling, confinement, and pedestal structure continued to improve with additional lithium, even after ELMs were completely suppressed. New analysis shows that toroidal rotation and ion temperature also increased continuously with additional lithium. Besides its evolution with additional lithium, we also characterize the time evolution of the ELM-free H-mode pedestal as average density rose and impurities accumulated. We find that the pedestal structure, divertor heat flux and Dalpha profiles, and inferred recycling coefficient did not change significantly, at least until radiative losses become dominant. This suggests that the low-recycling properties of lithium were not significantly degraded over the duration of the discharge.
Date: June 28, 2012
Creator: D.P. Boyle, J.M. Canik, R. Maing, P.B. Snyder, T.H. Osborne, and the NSTX Team
Object Type: Report
System: The UNT Digital Library
618-10 Burial Ground Trench Remediation and 618-10 and 618-11 Burial Ground Nonintrusive Characterization of Vertical Pipe Units Lessons Learned (open access)

618-10 Burial Ground Trench Remediation and 618-10 and 618-11 Burial Ground Nonintrusive Characterization of Vertical Pipe Units Lessons Learned

A “lessons learned” is a noteworthy practice or innovative approach that is captured and shared to promote repeat application, or an adverse work practice/experience that is captured and shared to avoid reoccurrence. This document provides the lessons learned identified by the 618-10 Burial Ground trench remediation and the 618-10 and 618-11 Burial Ground nonintrusive characterization of the vertical pipe units (VPUs).
Date: June 28, 2012
Creator: Darby, J. W.
Object Type: Report
System: The UNT Digital Library
Federal Funding of Presidential Nominating Conventions: Overview and Policy Options (open access)

Federal Funding of Presidential Nominating Conventions: Overview and Policy Options

None
Date: June 28, 2012
Creator: Garrett, R. Sam & Reese, Shawn
Object Type: Report
System: The UNT Digital Library
INDEPENDENT CONFIRMATORY SURVEY OF THE NUCLEAR RESEARCH LABORATORY AT THE UNIVERSITY OF ILLINOIS URBANA-CHAMPAIGN, ILLINOIS (open access)

INDEPENDENT CONFIRMATORY SURVEY OF THE NUCLEAR RESEARCH LABORATORY AT THE UNIVERSITY OF ILLINOIS URBANA-CHAMPAIGN, ILLINOIS

ORAU conducted confirmatory survey activities within the NRL at the University during the week of May 7, 2012. The survey activities included visual inspections/ assessments, surface activity measurements, and volumetric concrete sampling activities. During the course of the confirmatory activities, ORAU noted several issues with the survey-for-release activities performed at the University. Issues included inconsistencies with: survey unit classifications were not designated according to Multi-Agency Radiation Survey and Site Investigation Manual guidance; survey instrument calibrations were not representative of the radionuclides of concern; calculations for instrumentation detection capabilities did not align with the release criteria discussed in the licensee’s survey guidance documents; total surface activity measurements were in excess of the release criteria; and Co-60 and Eu-152 concentrations in the confirmatory concrete samples were above their respective guidelines. Based on the significant programmatic issues identified, ORAU cannot independently conclude that the NRL satisfied the requirements and limits for release of materials without radiological restrictions.
Date: June 28, 2012
Creator: HARPENAU, EVAN M.
Object Type: Report
System: The UNT Digital Library
A Measurement Management Technology for Improving Energy Efficiency in Data Centers and Telecommunication Facilities (open access)

A Measurement Management Technology for Improving Energy Efficiency in Data Centers and Telecommunication Facilities

Data center (DC) electricity use is increasing at an annual rate of over 20% and presents a concern for the Information Technology (IT) industry, governments, and the society. A large fraction of the energy use is consumed by the compressor cooling to maintain the recommended operating conditions for IT equipment. The most common way to improve the DC efficiency is achieved by optimally provisioning the cooling power to match the global heat dissipation in the DC. However, at a more granular level, the large range of heat densities of today's IT equipment makes the task of provisioning cooling power optimized to the level of individual computer room air conditioning (CRAC) units much more challenging. Distributed sensing within a DC enables the development of new strategies to improve energy efficiency, such as hot spot elimination through targeted cooling, matching power consumption at rack level with workload schedule, and minimizing power losses. The scope of Measurement and Management Technologies (MMT) is to develop a software tool and the underlying sensing technology to provide critical decision support and control for DC and telecommunication facilities (TF) operations. A key aspect of MMT technology is integration of modeling tools to understand how changes in one …
Date: June 28, 2012
Creator: Hamann, Hendrik
Object Type: Report
System: The UNT Digital Library
Computational Mechanics Research and Support for Aerodynamics and Hydraulics at THFRC, Year 2 Quarter 2 Progress Report (open access)

Computational Mechanics Research and Support for Aerodynamics and Hydraulics at THFRC, Year 2 Quarter 2 Progress Report

The computational fluid dynamics (CFD) and computational structural mechanics (CSM) focus areas at Argonne's Transportation Research and Analysis Computing Center (TRACC) initiated a project to support and compliment the experimental programs at the Turner-Fairbank Highway Research Center (TFHRC) with high performance computing based analysis capabilities in August 2010. The project was established with a new interagency agreement between the Department of Energy and the Department of Transportation to provide collaborative research, development, and benchmarking of advanced three-dimensional computational mechanics analysis methods to the aerodynamics and hydraulics laboratories at TFHRC for a period of five years, beginning in October 2010. The analysis methods employ well benchmarked and supported commercial computational mechanics software. Computational mechanics encompasses the areas of Computational Fluid Dynamics (CFD), Computational Wind Engineering (CWE), Computational Structural Mechanics (CSM), and Computational Multiphysics Mechanics (CMM) applied in Fluid-Structure Interaction (FSI) problems. The major areas of focus of the project are wind and water effects on bridges - superstructure, deck, cables, and substructure (including soil), primarily during storms and flood events - and the risks that these loads pose to structural failure. For flood events at bridges, another major focus of the work is assessment of the risk to bridges caused by …
Date: June 28, 2012
Creator: Lottes, S.A.; Bojanowski, C.; Shen, J.; Xie, Z.; Zhai, Y. (Energy Systems) & Center), (Turner-Fairbank Highway Research
Object Type: Report
System: The UNT Digital Library
ARM User Survey Report: Data Access, Quality, and Delivery (open access)

ARM User Survey Report: Data Access, Quality, and Delivery

The objective of this survey was to obtain user feedback to determine how users of the Atmospheric Radiation Measurement (ARM) Climate Research Facility Data Archive interact with the more than 2000 available types of datastreams. The survey also gathered information about data discovery and data quality. The Market and Competitive Analysis group at Pacific Northwest National Laboratory worked with web administrators to develop a landing page from which users could access the survey. A survey invitation was sent by ARM via email to about 6100 users on February 22, 2012. The invitation was also posted on the ARM website and Facebook page. Reminders were sent via e-mail and posted on Facebook while the survey was open, February 22-March 23, 2012.
Date: June 28, 2012
Creator: Mather, JH; Roeder, LR & Sivaraman, C
Object Type: Text
System: The UNT Digital Library
Foreign Travel Trip Report for LLNL Travel with DOE FES Funding (open access)

Foreign Travel Trip Report for LLNL Travel with DOE FES Funding

None
Date: June 28, 2012
Creator: Meier, E T
Object Type: Report
System: The UNT Digital Library
Electric Gradient Breakdown Results for the Orthogonal Box Cavity in a 3 T Magnetic Field (open access)

Electric Gradient Breakdown Results for the Orthogonal Box Cavity in a 3 T Magnetic Field

None
Date: June 28, 2012
Creator: Moretti, A.
Object Type: Report
System: The UNT Digital Library
ANALYSIS OF THE TANK 6F FINAL CHARACTERIZATION SAMPLES-2012 (open access)

ANALYSIS OF THE TANK 6F FINAL CHARACTERIZATION SAMPLES-2012

The Savannah River National Laboratory (SRNL) was requested by Savannah River Remediation (SRR) to provide sample preparation and analysis of the Tank 6F final characterization samples to determine the residual tank inventory prior to grouting. Fourteen residual Tank 6F solid samples from three areas on the floor of the tank were collected and delivered to SRNL between May and August 2011. These Tank 6F samples were homogenized and combined into three composite samples based on a proportion compositing scheme and the resulting composite samples were analyzed for radiological, chemical and elemental components. Additional measurements performed on the Tank 6F composite samples include bulk density and water leaching of the solids to account for water soluble components. The composite Tank 6F samples were analyzed and the data reported in triplicate. Sufficient quality assurance standards and blanks were utilized to demonstrate adequate characterization of the Tank 6F samples. The main evaluation criteria were target detection limits specified in the technical task request document. While many of the target detection limits were met for the species characterized for Tank 6F some were not met. In a few cases, the relatively high levels of radioactive species of the same element or a chemically similar …
Date: June 28, 2012
Creator: Oji, L.; Diprete, D.; Coleman, C.; Hay, M. & Shine, G.
Object Type: Report
System: The UNT Digital Library
The History of X-ray Free-Electron Lasers (open access)

The History of X-ray Free-Electron Lasers

The successful lasing at the SLAC National Accelerator Laboratory of the Linear Coherent Light Source (LCLS), the first X-ray free-electron laser (X-ray FEL), in the wavelength range 1.5 to 15 {angstrom}, pulse duration of 60 to few femtoseconds, number of coherent photons per pulse from 10{sup 13} to 10{sup 11}, is a landmark event in the development of coherent electromagnetic radiation sources. Until now electrons traversing an undulator magnet in a synchrotron radiation storage ring provided the best X-ray sources. The LCLS has set a new standard, with a peak X-ray brightness higher by ten orders of magnitudes and pulse duration shorter by three orders of magnitudes. LCLS opens a new window in the exploration of matter at the atomic and molecular scales of length and time. Taking a motion picture of chemical processes in a few femtoseconds or less, unraveling the structure and dynamics of complex molecular systems, like proteins, are some of the exciting experiments made possible by LCLS and the other X-ray FELs now being built in Europe and Asia. In this paper, we describe the history of the many theoretical, experimental and technological discoveries and innovations, starting from the 1960s and 1970s, leading to the development …
Date: June 28, 2012
Creator: Pellegrini, C. & /SLAC, /UCLA
Object Type: Article
System: The UNT Digital Library
The Development of High Speed Rail in the United States: Issues and Recent Events (open access)

The Development of High Speed Rail in the United States: Issues and Recent Events

This report looks at the different ways to construct a high speed rail (HSR) in the U.S., including estimates of construction costs.
Date: June 28, 2012
Creator: Peterman, David Randall; Frittelli, John & Mallett, William J.
Object Type: Report
System: The UNT Digital Library
Installation of a Low Flow Unit at the Abiquiu Hydroelectric Facility (open access)

Installation of a Low Flow Unit at the Abiquiu Hydroelectric Facility

Final Technical Report for the Recovery Act Project for the Installation of a Low Flow Unit at the Abiquiu Hydroelectric Facility. The Abiquiu hydroelectric facility existed with two each 6.9 MW vertical flow Francis turbine-generators. This project installed a new 3.1 MW horizontal flow low flow turbine-generator. The total plant flow range to capture energy and generate power increased from between 250 and 1,300 cfs to between 75 and 1,550 cfs. Fifty full time equivalent (FTE) construction jobs were created for this project - 50% (or 25 FTE) were credited to ARRA funding due to the ARRA 50% project cost match. The Abiquiu facility has increased capacity, increased efficiency and provides for an improved aquatic environment owing to installed dissolved oxygen capabilities during traditional low flow periods in the Rio Chama. A new powerhouse addition was constructed to house the new turbine-generator equipment.
Date: June 28, 2012
Creator: Richardson, Jack Q.
Object Type: Report
System: The UNT Digital Library
Plasma-based Accelerator with Magnetic Compression (open access)

Plasma-based Accelerator with Magnetic Compression

Electron dephasing is a major gain-inhibiting effect in plasma-based accelerators. A novel method is proposed to overcome dephasing, in which the modulation of a modest (#24; O(10 kG)), axial, uniform magnetic field in the acceleration channel leads to densification of the plasma through magnetic compression, enabling direct, time-resolved control of the plasma wave properties. The methodology is broadly applicable and can be optimized to improve the leading acceleration approaches, including plasma beat-wave, plasma wakefield, and laser wakefield acceleration. The advantages of magnetic compression compared to other proposed schemes to overcome dephasing are identified.
Date: June 28, 2012
Creator: Schmit, Paul F. & Fisch, Nathaniel J.
Object Type: Report
System: The UNT Digital Library
GLOBAL P-WAVE TOMOGRAPHY FOR IMPROVED TRAVEL TIME PREDICTIONS AND EVENT LOCATIONS (open access)

GLOBAL P-WAVE TOMOGRAPHY FOR IMPROVED TRAVEL TIME PREDICTIONS AND EVENT LOCATIONS

None
Date: June 28, 2012
Creator: Simmons, N A; Myers, S C; Johannesson, G & Matzel, E
Object Type: Article
System: The UNT Digital Library
Echo-Enabled Harmonic Generation (open access)

Echo-Enabled Harmonic Generation

A recently proposed concept of the Echo-Enabled Harmonic Generation (EEHG) FEL uses two laser modulators in combination with two dispersion sections to generate a high-harmonic density modulation in a relativistic beam. This seeding technique holds promise of a one-stage soft x-ray FEL that radiates not only transversely but also longitudinally coherent pulses. Currently, an experimental verification of the concept is being conducted at the SLAC National Accelerator Laboratory aimed at the demonstration of the EEHG.
Date: June 28, 2012
Creator: Stupakov, Gennady
Object Type: Article
System: The UNT Digital Library
Revisions Related to TWDB's Review Comments on BRACS Geophysical Log Database and Images (open access)

Revisions Related to TWDB's Review Comments on BRACS Geophysical Log Database and Images

A list and descriptions of actions taken to revise review comments on BRACS Geophysical log database and images.
Date: June 28, 2012
Creator: Texas Water Development Board
Object Type: Text
System: The Portal to Texas History