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Improved Biomass Utilization Through Remote Flow Sensing (open access)

Improved Biomass Utilization Through Remote Flow Sensing

The growth of the livestock industry provides a valuable source of affordable, sustainable, and renewable bioenergy, while also requiring the safe disposal of the large quantities of animal wastes (manure) generated at dairy, swine, and poultry farms. If these biomass resources are mishandled and underutilized, major environmental problems will be created, such as surface and ground water contamination, odors, dust, ammonia leaching, and methane emission. Anaerobic digestion of animal wastes, in which microorganisms break down organic materials in the absence of oxygen, is one of the most promising waste treatment technologies. This process produces biogas typically containing {approx}65% methane and {approx}35% carbon dioxide. The production of biogas through anaerobic digestion from animal wastes, landfills, and municipal waste water treatment plants represents a large source of renewable and sustainable bio-fuel. Such bio-fuel can be combusted directly, used in internal combustion engines, converted into methanol, or partially oxidized to produce synthesis gas (a mixture of hydrogen and carbon monoxide) that can be converted to clean liquid fuels and chemicals via Fischer-Tropsch synthesis. Different design and mixing configurations of anaerobic digesters for treating cow manure have been utilized commercially and/or tested on a laboratory scale. These digesters include mechanically mixed, gas recirculation mixed, …
Date: March 26, 2007
Creator: Al-Dahhan, Muthanna; Varma, Rajneesh; Karim, Khursheed; Vesvikar, Mehul; Hoffman, Rebecca; Depaoli, David et al.
Object Type: Report
System: The UNT Digital Library
Evaluation of ITER MSE Viewing Optics (open access)

Evaluation of ITER MSE Viewing Optics

The Motional Stark Effect (MSE) diagnostic on ITER determines the local plasma current density by measuring the polarization angle of light resulting from the interaction of a high energy neutral heating beam and the tokamak plasma. This light signal has to be transmitted from the edge and core of the plasma to a polarization analyzer located in the port plug. The optical system should either preserve the polarization information, or it should be possible to reliably calibrate any changes induced by the optics. This LLNL Work for Others project for the US ITER Project Office (USIPO) is focused on the design of the viewing optics for both the edge and core MSE systems. Several design constraints were considered, including: image quality, lack of polarization aberrations, ease of construction and cost of mirrors, neutron shielding, and geometric layout in the equatorial port plugs. The edge MSE optics are located in ITER equatorial port 3 and view Heating Beam 5, and the core system is located in equatorial port 1 viewing heating beam 4. The current work is an extension of previous preliminary design work completed by the ITER central team (ITER resources were not available to complete a detailed optimization of …
Date: March 26, 2007
Creator: Allen, S.; Lerner, S.; Morris, K.; Jayakumar, J.; Holcomb, C.; Makowski, M. et al.
Object Type: Report
System: The UNT Digital Library
Image Content Engine (ICE) (open access)

Image Content Engine (ICE)

The Image Content Engine (ICE) is being developed to provide cueing assistance to human image analysts faced with increasingly large and intractable amounts of image data. The ICE architecture includes user configurable feature extraction pipelines which produce intermediate feature vector and match surface files which can then be accessed by interactive relational queries. Application of the feature extraction algorithms to large collections of images may be extremely time consuming and is launched as a batch job on a Linux cluster. The query interface accesses only the intermediate files and returns candidate hits nearly instantaneously. Queries may be posed for individual objects or collections. The query interface prompts the user for feedback, and applies relevance feedback algorithms to revise the feature vector weighting and focus on relevant search results. Examples of feature extraction and both model-based and search-by-example queries are presented.
Date: March 26, 2007
Creator: Brase, J M
Object Type: Report
System: The UNT Digital Library
The Express-Star (Chickasha, Okla.), Ed. 1 Monday, March 26, 2007 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Monday, March 26, 2007

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: March 26, 2007
Creator: Bush, Kent
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Altus Times (Altus, Okla.), Vol. 108, No. 309, Ed. 1 Monday, March 26, 2007 (open access)

The Altus Times (Altus, Okla.), Vol. 108, No. 309, Ed. 1 Monday, March 26, 2007

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: March 26, 2007
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
Book Review Geostatistical Analysis of Compositional Data (open access)

Book Review Geostatistical Analysis of Compositional Data

Compositional data are represented as vector variables with individual vector components ranging between zero and a positive maximum value representing a constant sum constraint, usually unity (or 100 percent). The earth sciences are flooded with spatial distributions of compositional data, such as concentrations of major ion constituents in natural waters (e.g. mole, mass, or volume fractions), mineral percentages, ore grades, or proportions of mutually exclusive categories (e.g. a water-oil-rock system). While geostatistical techniques have become popular in earth science applications since the 1970s, very little attention has been paid to the unique mathematical properties of geostatistical formulations involving compositional variables. The book 'Geostatistical Analysis of Compositional Data' by Vera Pawlowsky-Glahn and Ricardo Olea (Oxford University Press, 2004), unlike any previous book on geostatistics, directly confronts the mathematical difficulties inherent to applying geostatistics to compositional variables. The book righteously justifies itself with prodigious referencing to previous work addressing nonsensical ranges of estimated values and error, spurious correlation, and singular cross-covariance matrices.
Date: March 26, 2007
Creator: Carle, S F
Object Type: Article
System: The UNT Digital Library

[Speaking]

Photograph of Francisco Antonio Alvarez Calderon, the new president of the Federation of Zacatecanos of Texas, speaking at a microphone during a gala dinner in Fort Worth. Several people are visible behind him, seated a table, but out of focus.
Date: March 26, 2007
Creator: Castillo, José L.
Object Type: Photograph
System: The UNT Digital Library
Failure Modes and Diagnostic Signatures Working Group - Ignition Diagnostics Requirements Update (open access)

Failure Modes and Diagnostic Signatures Working Group - Ignition Diagnostics Requirements Update

We have performed an initial assessment of the sensitivity of various expected ignition diagnostic signatures to ignition failure modes using one and two-dimensional hydrodynamics simulations and post-processed simulated diagnostic output. As a result of this assessment, we recommend several changes to the current requirements for the ignition diagnostic suite. These recommendations are summarized in Table 1.
Date: March 26, 2007
Creator: Cerjan, C.; Haan, S.; Hatchett, S. & Koch, J.
Object Type: Report
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 86, No. 119, Ed. 1 Monday, March 26, 2007 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 86, No. 119, Ed. 1 Monday, March 26, 2007

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: March 26, 2007
Creator: Clements, Clifford E.
Object Type: Newspaper
System: The Portal to Texas History
Large-timestep mover for particle simulations of arbitrarilymagnetized species (open access)

Large-timestep mover for particle simulations of arbitrarilymagnetized species

For self-consistent ion-beam simulations including electron motion, it is desirable to be able to follow electron dynamics accurately without being constrained by the electron cyclotron timescale. To this end, we have developed a particle-advance that interpolates between full particle dynamics and drift motion. By making a proper choice of interpolation parameter, simulation particles experience physically correct parallel dynamics, drift motion, and gyroradius when the timestep is large compared to the cyclotron period, though the effective gyro frequency is artificially low; in the opposite timestep limit, the method approaches a conventional Boris particle push. By combining this scheme with a Poisson solver that includes an interpolated form of the polarization drift in the dielectric response, the movers utility can be extended to higher-density problems where the plasma frequency of the species being advanced exceeds its cyclotron frequency. We describe a series of tests of the mover and its application to simulation of electron clouds in heavy-ion accelerators.
Date: March 26, 2007
Creator: Cohen, R. H.; Friedman, A.; Grote, D. P. & Vay, J. L.
Object Type: Article
System: The UNT Digital Library
Colliding with a crunching bubble (open access)

Colliding with a crunching bubble

In the context of eternal inflation we discuss the fate of Lambda = 0 bubbles when they collide with Lambda< 0 crunching bubbles. When the Lambda = 0 bubble is supersymmetric, it is not completely destroyed by collisions. If the domain wall separating the bubbles has higher tension than the BPS bound, it is expelled from the Lambda = 0 bubble and does not alter its long time behavior. If the domain wall saturates the BPS bound, then it stays inside the Lambda = 0 bubble and removes a finite fraction of future infinity. In this case, the crunch singularity is hidden behind the horizon of a stable hyperbolic black hole.
Date: March 26, 2007
Creator: Freivogel, Ben; Freivogel, Ben; Horowitz, Gary T. & Shenker, Stephen
Object Type: Article
System: The UNT Digital Library

Doctoral Recital: 2007-03-26 - Jay Gardner, tenor

Recital presented at the UNT College of Music Concert Hall in partial fulfillment of the Doctor of Musical Arts (DMA) degree
Date: March 26, 2007
Creator: Gardner, Jay
Object Type: Sound
System: The UNT Digital Library
Defense Acquisition: Use of Lead System Integrators (LSIs) — Background, Oversight Issues, and Options for Congress (open access)

Defense Acquisition: Use of Lead System Integrators (LSIs) — Background, Oversight Issues, and Options for Congress

Some in Congress have expressed concern about the government's use of private-sector lead system integrators (LSIs) for executing large, complex defense-related acquisition programs. LSIs are large, prime contractors hired to manage such programs.The 110th Congress has also introduced legislation to require the federal government to study the use of LSIs, and legislation wich would prohibit the use of LSIs for remaining contracts under the Deepwater Program. This report contains information on the background on LSIs, potential oversight issues for Congress, potential options for Congress, and legislative activity as related to this issue.
Date: March 26, 2007
Creator: Grasso, Valerie Bailey
Object Type: Report
System: The UNT Digital Library
Visual Analysis of Weblog Content (open access)

Visual Analysis of Weblog Content

In recent years, one of the advances of the World Wide Web is social media and one of the fastest growing aspects of social media is the blogosphere. Blogs make content creation easy and are highly accessible through web pages and syndication. With their growing influence, a need has arisen to be able to monitor the opinions and insight revealed within their content. In this paper we describe a technical approach for analyzing the content of blog data using a visual analytic tool, IN-SPIRE, developed by Pacific Northwest National Laboratory. We highlight the capabilities of this tool that are particularly useful for information gathering from blog data.
Date: March 26, 2007
Creator: Gregory, Michelle L.; Payne, Deborah A.; McColgin, Dave; Cramer, Nick O. & Love, Douglas V.
Object Type: Article
System: The UNT Digital Library
Development of Hfe Sections of Dg-1145. (open access)

Development of Hfe Sections of Dg-1145.

For the licensing of the current fleet of commercial nuclear power plants (NPPs), the Nuclear Regulatory Commission (NRC) used two key documents, NUREG-0800 and Regulatory Guide (RG) 1.70. RG 1.70 provided guidance to applicants on the contents needed in their Safety Analysis Reports (SARs) submitted as part of their application to construct or operate an NPP. NUREG-0800, the NRC Standard Review Plan (SRP), provides guidance to the NRR staff reviewers on performing their safety reviews of these applications. As part of the preparation for a new wave of improved NPP designs the NRC is in the process of updating the SRP and is also developing a new RG designated as draft RG or DG-1145, ''Combined License Applications for Nuclear Power Plants (LWR Edition).'' This will eventually become RG 1.206 and will take the place of RG 1.70. This will provide guidance for combined license (COL) applicants, as well as for other 10CFR Part 52 variations that are permitted.
Date: March 26, 2007
Creator: Higgins, J. C.; Ohara, J. M. & Bongarra, J.
Object Type: Article
System: The UNT Digital Library
Nuclear Energy Policy (open access)

Nuclear Energy Policy

This report discusses the nuclear energy policy issues facing Congress that include the implementation of federal incentives for new commercial reactors, radioactive waste management policy, research and development priorities, power plant safety and regulation, nuclear weapons proliferation, and security against terrorist attacks.
Date: March 26, 2007
Creator: Holt, Mark
Object Type: Report
System: The UNT Digital Library
RCRA Assessment Plan for Single-Shell Tank Waste Management Area TX-TY (open access)

RCRA Assessment Plan for Single-Shell Tank Waste Management Area TX-TY

WMA TX-TY contains underground, single-shell tanks that were used to store liquid waste that contained chemicals and radionuclides. Most of the liquid has been removed, and the remaining waste is regulated under the RCRA as modi¬fied in 40 CFR Part 265, Subpart F and Washington State’s Hazardous Waste Management Act . WMA TX-TY was placed in assessment monitoring in 1993 because of elevated specific conductance. A groundwater quality assessment plan was written in 1993 describing the monitoring activities to be used in deciding whether WMA TX-TY had affected groundwater. That plan was updated in 2001 for continued RCRA groundwater quality assessment as required by 40 CFR 265.93 (d)(7). This document further updates the assessment plan for WMA TX-TY by including (1) information obtained from ten new wells installed at the WMA after 1999 and (2) information from routine quarterly groundwater monitoring during the last five years. Also, this plan describes activities for continuing the groundwater assessment at WMA TX TY.
Date: March 26, 2007
Creator: Horton, Duane G.
Object Type: Report
System: The UNT Digital Library
Poland Becoming a Member of the Global Nuclear Energy Partnership, Vol. 1. (open access)

Poland Becoming a Member of the Global Nuclear Energy Partnership, Vol. 1.

Within a constrained carbon environment, the risks of future natural gas supply, and the need to move to market-based electricity prices, the study team found: (1) the deployment of new nuclear energy in Poland itself is very competitive in the next decade or two; (2) if such generation could be made available to Poland prior to deployment of its own nuclear generation facilities, Poland would benefit from partnering with its Baltic neighbors to import electricity derived from new nuclear generation facilities sited in Lithuania; and (3) Poland appears to be a good candidate for a partnership in the Global Nuclear Energy Partnership (GNEP) as an emerging nuclear energy country.
Date: March 26, 2007
Creator: Koritarov, V. K.; Conzelmann, G.; Cirillo, R. R. & Goldberg, S. M.
Object Type: Report
System: The UNT Digital Library
Poland Becoming a Member of the Global Nuclear Energy Partnership, Vol. 2. (open access)

Poland Becoming a Member of the Global Nuclear Energy Partnership, Vol. 2.

Within a constrained carbon environment, the risks of future natural gas supply, and the need to move to market-based electricity prices, the study team found: (1) the deployment of new nuclear energy in Poland itself is very competitive in the next decade or two; (2) if such generation could be made available to Poland prior to deployment of its own nuclear generation facilities, Poland would benefit from partnering with its Baltic neighbors to import electricity derived from new nuclear generation facilities sited in Lithuania; and (3) Poland appears to be a good candidate for a partnership in the Global Nuclear Energy Partnership (GNEP) as an emerging nuclear energy country.
Date: March 26, 2007
Creator: Koritarov, V. K.; Conzelmann, G.; Cirillo, R. R. & Goldberg, S. M.
Object Type: Report
System: The UNT Digital Library
Special population planner, version 4.0. (open access)

Special population planner, version 4.0.

Emergencies happen every day. Many are caused by storms or auto accidents and can be planned for, if not predicted. Emergencies resulting from natural hazards often affect a large number of people, and planning for them can be difficult, since knowledge of the needs of the people involved is generally unavailable. Emergencies resulting from accidents at industrial and military facilities can also be large scale in nature if people must be evacuated or sheltered in place. Federal planning for large scale emergencies is the responsibility of the Federal Emergency Management Agency (FEMA), which provides assistance to various emergency management agencies at the national, state and local level. More information about FEMA is available at http://www.fema.gov/. The purpose of the Special Population Planner (SPP) is to help emergency planners address the needs of persons with special needs. The exact definition of 'special population' is a policy decision. Policymakers have included a variety of groups in this term, such as persons with disabilities, those who do not have vehicles with which to evacuate, children who are unattended at times (latchkey children), and many others. The SPP was developed initially for the Alabama Emergency Management Agency as part of its Chemical Stockpile Emergency …
Date: March 26, 2007
Creator: Kuiper, J.; Tanzman, E. & Metz, W.
Object Type: Report
System: The UNT Digital Library
Synthesis of Non-molecular Nitrogen Phases at Mbar Pressures by Direct Laser-heating (open access)

Synthesis of Non-molecular Nitrogen Phases at Mbar Pressures by Direct Laser-heating

Direct laser heating of molecular N2 to above 1400 K at 120-130 GPa results in the formation of a reddish amorphous phase and a transparent crystalline solid above 2000 K. Raman and x-ray data confirm that the transparent phase is cubic-gauche nitrogen (cg-N), while the reddish color of the amorphous phase might indicate the presence of N=N dish bonds. The quenched amorphous phase is stable down to at least 70GPa, analogous to cg-N, and could be a new non-molecular phase or an extension of the already known {eta}-phase. A chemo-physical phase diagram is presented which emphasizes the difference between pressure- and temperature-induced transitions from molecular to non-molecular solids, as found in other low Z systems.
Date: March 26, 2007
Creator: Lipp, M. J.; Klepeis, J. P.; Baer, B. J.; Cynn, H.; Evans, W. J.; Iota, V. et al.
Object Type: Article
System: The UNT Digital Library
Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 92, No. 116, Ed. 1 Monday, March 26, 2007 (open access)

Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 92, No. 116, Ed. 1 Monday, March 26, 2007

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising.
Date: March 26, 2007
Creator: Mattox, Jami
Object Type: Newspaper
System: The Gateway to Oklahoma History
Climate response to projected changes in short-lived species under an A1B scenario from 2000-2050 in the GISS climate model (open access)

Climate response to projected changes in short-lived species under an A1B scenario from 2000-2050 in the GISS climate model

We investigate the climate forcing from and response to projected changes in short-lived species and methane under the A1B scenario from 2000-2050 in the GISS climate model. We present a meta-analysis of new simulations of the full evolution of gas and aerosol species and other existing experiments with variations of the same model. The comparison highlights the importance of several physical processes in determining radiative forcing, especially the effect of climate change on stratosphere-troposphere exchange, heterogeneous sulfate-nitrate-dust chemistry, and changes in methane oxidation and natural emissions. However, the impact of these fairly uncertain physical effects is substantially less than the difference between alternative emission scenarios for all short-lived species. The net global mean annual average direct radiative forcing from the short-lived species is .02 W/m{sup 2} or less in our projections, as substantial positive ozone forcing is largely offset by negative aerosol direct forcing. Since aerosol reductions also lead to a reduced indirect effect, the global mean surface temperature warms by {approx}0.07 C by 2030 and {approx}0.13 C by 2050, adding 19% and 17%, respectively, to the warming induced by long-lived greenhouse gases. Regional direct forcings are large, up to 3.8 W/m{sup 2}. The ensemble-mean climate response shows little regional …
Date: March 26, 2007
Creator: Menon, Surabi; Shindell, Drew T.; Faluvegi, Greg; Bauer, Susanne E.; Koch, Dorothy M.; Unger, Nadine et al.
Object Type: Article
System: The UNT Digital Library
Evaluation of Neutron Irradiated Silicon Carbide and Silicon Carbide Composites (open access)

Evaluation of Neutron Irradiated Silicon Carbide and Silicon Carbide Composites

The effects of fast neutron irradiation on SiC and SiC composites have been studied. The materials used were chemical vapor deposition (CVD) SiC and SiC/SiC composites reinforced with either Hi-Nicalon{trademark} Type-S, Hi-Nicalon{trademark} or Sylramic{trademark} fibers fabricated by chemical vapor infiltration. Statistically significant numbers of flexural samples were irradiated up to 4.6 x 10{sup 25} n/m{sup 2} (E>0.1 MeV) at 300, 500 and 800 C in the High Flux Isotope Reactor at Oak Ridge National Laboratory. Dimensions and weights of the flexural bars were measured before and after the neutron irradiation. Mechanical properties were evaluated by four point flexural testing. Volume increase was seen for all bend bars following neutron irradiation. Magnitude of swelling depended on irradiation temperature and material, while it was nearly independent of irradiation fluence over the fluence range studied. Flexural strength of CVD SiC increased following irradiation depending on irradiation temperature. Over the temperature range studied, no significant degradation in mechanical properties was seen for composites fabricated with Hi-Nicalon{trademark} Type-S, while composites reinforced with Hi-Nicalon{trademark} or Sylramic fibers showed significant degradation. The effects of irradiation on the Weibull failure statistics are also presented suggesting a reduction in the Weibull modulus upon irradiation. The cause of this potential …
Date: March 26, 2007
Creator: Newsome G, Snead L, Hinoki T, Katoh Y, Peters D
Object Type: Article
System: The UNT Digital Library