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Accelerator and Ion Beam Tradeoffs for Studies of Warm DenseMatter (open access)

Accelerator and Ion Beam Tradeoffs for Studies of Warm DenseMatter

One approach for heating a target to ''Warm Dense Matter'' conditions (similar, for example, to the interiors of giant planets or certain stages in inertial confinement fusion targets), is to use intense ion beams as the heating source (see refs.[6] and [7] and references therein for motivation and accelerator concepts). By consideration of ion beam phase-space constraints, both at the injector, and at the final focus, and consideration of simple equations of state and relations for ion stopping, approximate conditions at the target foil may be calculated. Thus, target temperature and pressure may be calculated as a function of ion mass, ion energy, pulse duration, velocity tilt, and other accelerator parameters. We connect some of these basic parameters to help search the extensive parameter space including ion mass, ion energy, total charge in beam pulse, beam emittance, target thickness and density.
Date: January 30, 2006
Creator: Barnard, J. J.; Briggs, R. J.; Callahan, D. A.; Davidson, R. C.; Friedman, A.; Grisham, L. et al.
Object Type: Article
System: The UNT Digital Library
Acoustic Doppler Current Profiler Measurements in the Tailrace at John Day Dam (open access)

Acoustic Doppler Current Profiler Measurements in the Tailrace at John Day Dam

Acoustic Doppler current profilers (ADCPs) were used to measure water velocities in the tailrace at John Day Dam over a two-week period in February 2005. Data were collected by the Pacific Northwest National Laboratory for the Hydraulic Design Section, Portland District, U.S. Army Corps of Engineers (USACE). The objective of this project was therefore to collect field measurements of water velocities in the near-field draft tube exit zone as well as the far-field tailrace to be used for improving these models. Field data were collected during the project using five separate ADCPs. Mobile ADCP data were collected using two ADCPs mounted on two separate boats. Data were collected by either holding the boat on-station at pre-defined locations for approximately 10 minutes or in moving transect mode when the boat would move over large distances during the data collection. Results from the mobile ADCP survey indicated a complex hydrodynamic flow field in the tailrace downstream of John Day Dam. A large gyre was noted between the skeleton section of the powerhouse and non-spilling portion of the spillway. Downstream of the spillway, the spillway flow is constrained against the navigation lock guide wall, and large velocities were noted in this region. Downstream …
Date: January 30, 2006
Creator: Cook, Chris B.; Dibrani, Berhon; Serkowski, John A.; Richmond, Marshall C.; Titzler, P. Scott & Dennis, Gary W.
Object Type: Report
System: The UNT Digital Library
AIDS in Africa (open access)

AIDS in Africa

Sub-Saharan Africa has been far more severely affected by AIDS than any other part of the world. The United Nations reports that 25.8 million adults and children are infected with the HIV virus in the region, which has about 11.15% of the world's population but more than 64% of the worldwide total of infected people. This report discusses this issue in detail, including the cause of the African AIDS epidemic, the social and economic consequences, response and treatment, and U.S. policy.
Date: January 30, 2006
Creator: Cook, Nicolas
Object Type: Report
System: The UNT Digital Library
Altus Times (Altus, Okla.), Vol. 107, No. 255, Ed. 1 Monday, January 30, 2006 (open access)

Altus Times (Altus, Okla.), Vol. 107, No. 255, Ed. 1 Monday, January 30, 2006

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: January 30, 2006
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
Amplitude Dependence of Time of Flight. (open access)

Amplitude Dependence of Time of Flight.

Machida found in tracking studies [Shinji Machida, presentation at the FFAG05 Workshop, Kyoto University Research Reactor Institute, Osaka, Japan, 5-9 December 2005] that the time of flight in a linear non-scaling FFAG depended on the transverse amplitude of the particles. I compute a relationship between the transverse amplitude dependence of the time of flight and the variation of tune with energy and explain its physical origin.
Date: January 30, 2006
Creator: Berg, J. S.
Object Type: Article
System: The UNT Digital Library
An analysis of model tropospheric response to various forcings (open access)

An analysis of model tropospheric response to various forcings

None
Date: January 30, 2006
Creator: Hnilo, J J & Christy, J R
Object Type: Article
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 85, No. 52, Ed. 1 Monday, January 30, 2006 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 85, No. 52, Ed. 1 Monday, January 30, 2006

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: January 30, 2006
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
Compaction of Expancel Microspheres and Epoxy Foam to 3 GPa (open access)

Compaction of Expancel Microspheres and Epoxy Foam to 3 GPa

Pressure-volume relationships were measured for unexpanded Expancel microspheres, epoxy foam and one specimen of crushed foam powder. The specimens were jacketed in tin canisters and compressed at ambient temperature and low strain rates to 3 GPa in a solid medium press. Pressures were corrected for friction, and specimen volumes were calculated relative to a nickel standard. The pressure-volume curves for each material show large volume reductions at pressures below 0.1 GPa. The curves stiffen sharply at or near full density. Relatively little volume reduction is observed above 0.1 GPa, and most is recovered on unloading. The energy expended in compressing the materials to 3 GPa and the energy recovered on unloading were determined by numerically integrating the pressure-volume curves. The net energy, which includes absorbed energy, was found to be small. Compressibilities and bulk moduli were determined from the slopes of the pressure-volume curves. The Expancel bulk modulus above 0.1 GPa was found to be similar to that of isopentane. The pressure-volume data were fit to a model from the ceramics literature (Kawakita and Ludde, 1970). The model fits provided estimates of the initial specimen porosities and room pressure bulk moduli.
Date: January 30, 2006
Creator: Carlson, S R; Bonner, B P; Ryerson, F J & Chow, C S
Object Type: Report
System: The UNT Digital Library
Competitive Sourcing Legislation (open access)

Competitive Sourcing Legislation

This report provides an overview of the competitive sourcing legislation. Until the late 1990's, the the executive branch, namely OMB, almost exclusively, led the competitive sourcing effort, issuing revisions to the circular, overseeing implementation of the policy, and providing guidance to agencies.
Date: January 30, 2006
Creator: Halchin, L. Elaine
Object Type: Report
System: The UNT Digital Library
Correct Tracking in FFAGS (open access)

Correct Tracking in FFAGS

Fixed field alternating gradient accelerators have many features which require careful modeling in simulation. They accept beams over an extremely large momentum range, generally at least a factor of 2. They often use magnets whose lengths are comparable to their apertures. The beam often makes large angles with respect to the magnet axis and pole face normal. In some applications (muons in particular), the beam occupies a substantial fraction of the magnet aperture. The longitudinal dynamics in these machines often differ significantly from what one finds in more conventional machines such as synchrotrons. These characteristics require that simulation codes be careful to avoid inappropriate approximations in describing particle motion in FFAGs. One must properly treat the coordinate system geometry independently from the magnetic fields. One cannot blindly assume that phase space variables are small. One must take magnet end fields properly into account. Finally, one must carefully consider what it means to have a ''matched'' distribution that is injected into these machines.
Date: January 30, 2006
Creator: Berg, J. S.
Object Type: Article
System: The UNT Digital Library
COUPLED MULTI-ELECTRODE INVESTIGATION OF CREVICE CORROSION OF 316 STAINLESS STEEL (open access)

COUPLED MULTI-ELECTRODE INVESTIGATION OF CREVICE CORROSION OF 316 STAINLESS STEEL

Crevice corrosion is currently studied using either one of two techniques depending on the data needed. The first method is a multi-crevice former over a metallic sample; this provides information on the severity of crevice corrosion (depth, position, frequency) but delivers little to no electrochemical information [1]. The second method involves the potentiodynamic or potentiostatic study of an uncreviced sample in model crevice solution or under a crevice former in aggressive solution [2]. Crevice corrosion is highly dependent on the position in the crevice. The distance from the crevice mouth will affect the depth of attack, the solution composition and pH, and the ohmic drop and the true potential in the crevice [3-6]. These in turn affect the current density as a function of potential and position. A Multi-Channel Micro-Electrode Analyzer (MMA) has been recently used to demonstrate the interaction between localized corrosion sites (pitting corrosion and intergranular corrosion) [7]. MMA can provide spatial resolution of electrochemical properties in the crevice. By coupling such a tool with scaling laws derived from experimental data (a simple equation linking the depth of crevice corrosion initiation to the crevice gap), it is possible to produce highly instrumented crevices, rescaled to enable spatial resolution …
Date: January 30, 2006
Creator: Scully, F. Bocher and J. R.
Object Type: Article
System: The UNT Digital Library
COUPLED MULTI-ELECTRODE INVESTIGATION OF CREVICE CORROSION OF 316 STAINLESS STEEL (open access)

COUPLED MULTI-ELECTRODE INVESTIGATION OF CREVICE CORROSION OF 316 STAINLESS STEEL

Crevice corrosion is currently studied using either one of two techniques depending on the data needed. The first method is a multi-crevice former over a metallic sample; this provides information on the severity of crevice corrosion (depth, position, frequency) but delivers little to no electrochemical information [1]. The second method involves the potentiodynamic or potentiostatic study of an uncreviced sample in model crevice solution or under a crevice former in aggressive solution [2]. Crevice corrosion is highly dependent on the position in the crevice. The distance from the crevice mouth will affect the depth of attack, the solution composition and pH, and the ohmic drop and the true potential in the crevice [3-6]. These in turn affect the current density as a function of potential and position. An Multi-Channel Micro-Electrode Analyzer' (MMA) has been recently used to demonstrate the interaction between localized corrosion sites (pitting corrosion and intergranular corrosion) [7]. MMA can provide spatial resolution of electrochemical properties in the crevice. By coupling such a tool with scaling laws derived from experimental data (a simple equation linking the depth of crevice corrosion initiation to the crevice gap), it is possible to produce highly instrumented crevices, rescaled to enable spatial resolution …
Date: January 30, 2006
Creator: F. Bocher, J. R. Scully
Object Type: Article
System: The UNT Digital Library
Defense Acquisitions: DOD Management Approach and Processes Not Well-Suited to Support Development of Global Information Grid (open access)

Defense Acquisitions: DOD Management Approach and Processes Not Well-Suited to Support Development of Global Information Grid

A letter report issued by the Government Accountability Office with an abstract that begins "Department of Defense (DOD) officials currently estimate that the department will spend approximately $34 billion through 2011 to develop the core network of the Global Information Grid (GIG), a large and complex undertaking intended to provide on-demand and real-time data and information to the warfighter. DOD views the GIG as the cornerstone of information superiority, a key enabler of network-centric warfare, and a pillar of defense transformation. A high degree of coordination and cooperation is needed to make the GIG a reality. In prior work GAO found that enforcing investment decisions across the military services and assuring management attention and oversight of the GIG effort were key management challenges facing DOD. This report assesses (1) the management approach that DOD is using to develop the GIG and (2) whether DOD's three major decision-making processes support the development of a crosscutting, departmentwide investment, such as the GIG."
Date: January 30, 2006
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Design and implementation of an emergency environmental responsesystem to protect migrating salmon in the lower San Joaquin River,California (open access)

Design and implementation of an emergency environmental responsesystem to protect migrating salmon in the lower San Joaquin River,California

In the past decade tens of millions of dollars have beenspent by water resource agencies in California to restore the nativesalmon fishery in the San Joaquin River and its major tributaries. Anexcavated deep water ship channel (DWSC), through which the river runs onits way to the Bay/Delta and Pacific Ocean, experiences episodes of lowdissolved oxygen which acts as a barrier to anadromous fish migration anda threat to the long-term survival of the salmon run. An emergencyresponse management system is under development to forecast theseepisodes of low dissolved oxygen and to deploy measures that will raisedissolved oxygen concentrations to prevent damage to the fisheryresource. The emergency response management system has been designed tointeract with a real-time water quality monitoring network and is servedby a comprehensive data management and forecasting model toolbox. TheBay/Delta and Tributaries (BDAT) Cooperative Data Management System is adistributed, web accessible database that contains terabytes ofinformation on all aspects of the ecology of the Bay/Delta and upperwatersheds. The complexity of the problem dictates data integration froma variety of monitoring programs. A unique data templating system hasbeen constructed to serve the needs of cooperating scientists who wish toshare their data and to simplify and streamline data uploading into themaster database. …
Date: January 30, 2006
Creator: Quinn, Nigel W.T. & Jacobs, Karl C.
Object Type: Article
System: The UNT Digital Library
Development of a Black Carbon Standard for Thermal-OpticalAnalysis (open access)

Development of a Black Carbon Standard for Thermal-OpticalAnalysis

Carbonaceous aerosols affect air quality and climate, but measurements of black (BC) and organic (OC) carbon concentrations are very uncertain. Many variants of the thermal-optical analysis (TOA) method exist, and more than a decade of research has not resolved the differences in their estimates of OC and BC (i.e., the OC/BC split). This is largely due to the lack of a BC standard. Without a BC standard, the accuracy of TOA measurements of OC and BC cannot be determined. The research goal is to develop a method of producing BC standards that can be used to determine the accuracy in TOA measurements of OC and BC. The uncertainty in TOA measurements is due to the presence of both OC and BC in particulate matter. Whereas measuring total carbon (TC) is straightforward, OC pyrolysis and charring and premature evolution of BC render determination of the OC/BC split uncertain (and method dependent) (1,2,3). If a particulate matter sample containing only OC or BC was analyzed by TOA, there would be little uncertainty in the measurement. Our approach to developing a standard for TOA, therefore, is to (1) generate particulate matter composed only of BC and fully characterize the physical and optical properties …
Date: January 30, 2006
Creator: Kirchstetter, Thomas
Object Type: Report
System: The UNT Digital Library
Effect of Crevice Former on Corrosion Damage Propagation (open access)

Effect of Crevice Former on Corrosion Damage Propagation

None
Date: January 30, 2006
Creator: J. H. Payer, U. Landau, X. Shan, A. S. Agarwal
Object Type: Article
System: The UNT Digital Library
An Emergency Communications Safety Net: Integrating 911 and Other Services (open access)

An Emergency Communications Safety Net: Integrating 911 and Other Services

The 9/11 Commission Report recommended that 911 call centers — also called Public Safety Answering Points, or PSAPs — be included in planning for emergency responses.1 Congress, which has since 1999 passed two bills to further the deployment of 911, is reviewing ways to expand 911 capabilities and make it more accessible and effective. Congress is also evaluating ways to improve emergency alerts2 and interoperable communications for public safety.3 Operational convergence of emergency communications seems to many to be inevitable, a question of “when,” not “if.” This report deals primarily with 911 and its recent history. It also summarizes some of the proposals that would improve 911 through new approaches and integration with other services.
Date: January 30, 2006
Creator: Moore, Linda K.
Object Type: Report
System: The UNT Digital Library
Enhanced Attenuation: A Reference Guide On Approaches To Increase The Natural Treatment Capacity Of A System (open access)

Enhanced Attenuation: A Reference Guide On Approaches To Increase The Natural Treatment Capacity Of A System

The objective of this document is to explore the realm of enhancements to natural attenuation processes for cVOCs and review examples that have been proposed, modeled, and implemented. We will identify lessons learned from these case studies to confirm that enhancements are technically feasible and have the potential to achieve a favorable, cost-effective contaminant mass balance. Furthermore, we hope to determine if opportunities for further improvement of the enhancements exist and suggest areas where new and innovative types of enhancements might be possible.
Date: January 30, 2006
Creator: Vangelas, K
Object Type: Report
System: The UNT Digital Library
Estimation of Failure Rates of Digital Components Using a Hierarchical Bayesian Method. (open access)

Estimation of Failure Rates of Digital Components Using a Hierarchical Bayesian Method.

One of the greatest challenges in evaluating reliability of digital I&C systems is how to obtain better failure rate estimates of digital components. A common practice of the digital component failure rate estimation is attempting to use empirical formulae to capture the impacts of various factors on the failure rates. The applicability of an empirical formula is questionable because it is not based on laws of physics and requires good data, which is scarce in general. In this study, the concept of population variability of the Hierarchical Bayesian Method (HBM) is applied to estimating the failure rate of a digital component using available data. Markov Chain Monte Carlo (MCMC) simulation is used to implement the HBM. Results are analyzed and compared by selecting different distribution types and priors distributions. Inspired by the sensitivity calculations and based on review of analytic derivations, it seems reasonable to suggest avoiding the use of gamma distribution in two-stage Bayesian analysis and HBM analysis.
Date: January 30, 2006
Creator: Yue, M. & Chu, T. L.
Object Type: Article
System: The UNT Digital Library
Exhaust Aftertreatment and Low Pressure Loop EGR Applied to an Off-Highway Engine (open access)

Exhaust Aftertreatment and Low Pressure Loop EGR Applied to an Off-Highway Engine

The goal of the project was to demonstrate that low pressure loop EGR incorporating a diesel oxidation catalyst (DOC) and a diesel particulate filter (DPF) can be applied to an off-highway engine to meet Tier 3 (Task I) and Interim Tier 4 (Task II) off-road emissions standards. Task I data was collected using a John Deere 8.1 liter engine modified with a low pressure loop EGR system. The engine and EGR system was optimized and final data over the ISO 8178 eight mode test indicated the NOx emissions were less than 4 g/kWh and the PM was less than 0.02 g/kWh which means the engine met the Tier 3 off-road standard. Considerable experimental data was collected and used by Michigan Tech University to develop and calibrate the MTU-Filter 1D DPF model. The MTU-Filter 1D DPF code predicts the particulate mass evolution (deposition and oxidation) in the diesel particulate filter (DPF) during simultaneous loading and during thermal and NO{sub 2}-assisted regeneration conditions. It also predicts the pressure drop across the DPF, the flow and temperature fields, the solid filtration efficiency and the particle number distribution downstream of the DPF. A DOC model was also used to predict the NO{sub 2} upstream …
Date: January 30, 2006
Creator: Baumgard, Kirby; Triana, Antonio; Johnson, John; Yang, Song & Premchand, Kiran
Object Type: Report
System: The UNT Digital Library
The Express-Star (Chickasha, Okla.), Ed. 1 Monday, January 30, 2006 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Monday, January 30, 2006

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: January 30, 2006
Creator: Bush, Kent
Object Type: Newspaper
System: The Gateway to Oklahoma History
Field Ionization of Neutral Litium Vapor Using a 28.5 GeV Electron Beam (open access)

Field Ionization of Neutral Litium Vapor Using a 28.5 GeV Electron Beam

The E164/E164X plasma wakefield experiment studies beam-plasma interactions at the Stanford Linear Acceleration Center (SLAC). Due to SLAC's recent ability to variably compress bunches longitudinally from 650 {micro}m down to 20 {micro}m, the incoming beam is sufficiently dense to field ionize the neutral lithium (Li) vapor. The field ionization effects are characterized by the beams energy loss through the Li vapor column. Experiment results are presented.
Date: January 30, 2006
Creator: O'Connell, C. L.; Barnes, C. D.; Decker, F. J.; Hogan, M. J.; Iverson, R.; Krejcik, P. et al.
Object Type: Article
System: The UNT Digital Library
[Funeral Program for Tom C. Makey, Jr., January 30, 2006] (open access)

[Funeral Program for Tom C. Makey, Jr., January 30, 2006]

Funeral program for Mr. Tom C. Makey, Jr., born November 18, 1944. The funeral was held Monday, January 30, 2006 at Greater Faith Temple Apostolic Church, officiated by Dist. Elder Douglass Thompson. Funeral arrangements were made through Lewis Funeral Home and he was buried in Fort Sam Houston National Cemetery near San Antonio, Texas.
Date: January 30, 2006
Creator: unknown
Object Type: Pamphlet
System: The Portal to Texas History
Hanford Site River Protection Project (RPP) Tank Farm Closure (open access)

Hanford Site River Protection Project (RPP) Tank Farm Closure

The U. S. Department of Energy, Office of River Protection and the CH2M HILL Hanford Group, Inc. are responsible for the operations, cleanup, and closure activities at the Hanford Tank Farms. There are 177 tanks overall in the tank farms, 149 single-shell tanks (see Figure 1), and 28 double-shell tanks (see Figure 2). The single-shell tanks were constructed 40 to 60 years ago and all have exceeded their design life. The single-shell tanks do not meet Resource Conservation and Recovery Act of 1976 [1] requirements. Accordingly, radioactive waste is being retrieved from the single-shell tanks and transferred to double-shell tanks for storage prior to treatment through vitrification and disposal. Following retrieval of as much waste as is technically possible from the single-shell tanks, the Office of River Protection plans to close the single-shell tanks in accordance with the Hanford Federal Facility Agreement and Consent Order [2] and the Atomic Energy Act of 1954 [3] requirements. The double-shell tanks will remain in operation through much of the cleanup mission until sufficient waste has been treated such that the Office of River Protection can commence closing the double-shell tanks. At the current time, however, the focus is on retrieving waste and closing …
Date: January 30, 2006
Creator: Jaraysi, M. N.; Smith, Z.; Quintero, R.; Burandt, M. B. & Hewitt, W.
Object Type: Article
System: The UNT Digital Library