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Telecommunications: FCC Needs to Improve Its Ability to Monitor and Determine the Extent of Competition in Dedicated Access Services (open access)

Telecommunications: FCC Needs to Improve Its Ability to Monitor and Determine the Extent of Competition in Dedicated Access Services

A letter report issued by the Government Accountability Office with an abstract that begins "Government agencies and businesses that require significant capacity to meet voice and data needs depend on dedicated access services. This segment of the telecommunications market generated about $16 billion in revenues for the major incumbent telecommunications firms in 2005. The Federal Communications Commission (FCC) has historically regulated dedicated access prices. With the Telecommunications Act of 1996, FCC reformed its rules to rely on competition to bring about cost-based pricing. Starting in 2001, FCC granted pricing flexibility on the basis of a proxy measure of competition. GAO examined (1) the extent that alternatives are available in areas where FCC granted pricing flexibility, (2) how prices have changed since the granting of pricing flexibility, and the effect on government agencies, and (3) how FCC monitors competition. GAO's work included analyzing data on competitive alternatives, list prices, and average revenue, and interviewing FCC officials and industry representatives."
Date: November 29, 2006
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Chemical reaction rates using the semiclassical Van-Vleck initialvalue representation (open access)

Chemical reaction rates using the semiclassical Van-Vleck initialvalue representation

A semiclassical IVR formulation using the Van-Vleck propagator has been used to calculate the flux correlation function and thereby reaction rate constants. This Van-Vleck formulation of the flux-flux correlation function is computationally as simple as the classical Wigner model. However unlike the latter, it has the ability to capture quantum interference/coherence effects. Classical trajectories are evolved starting from the dividing surface that separates reactants and products, and are evolved negatively in time. This formulation has been tested on model problems ranging from the Eckart barrier, double well to the collinear H + H{sub 2}.
Date: November 29, 2006
Creator: Venkataraman, Charulatha & Miller, William H.
Object Type: Article
System: The UNT Digital Library
Evidence for Merging or Disruption of Red Galaxies from the Evolution of Their Clustering (open access)

Evidence for Merging or Disruption of Red Galaxies from the Evolution of Their Clustering

The formation and evolution of massive red galaxies form a crucial test of theories of galaxy formation based on hierarchical assembly. In this Letter we use observations of the clustering of luminous red galaxies from the Boötes field and N-body simulations to argue that about of the most luminous satellite galaxies appear to undergo merging or disruption within massive halos between and 0.5.
Date: November 29, 2006
Creator: White, Martin; White, Martin; Zheng, Zheng; Brown, Michael J. I.; Dey, Arjun & Jannuzi, Buell T.
Object Type: Article
System: The UNT Digital Library
Comparison of kinetic and equilibrium reaction models insimulating gas hydrate behavior in porous media (open access)

Comparison of kinetic and equilibrium reaction models insimulating gas hydrate behavior in porous media

In this study we compare the use of kinetic and equilibriumreaction models in the simulation of gas (methane) hydrate behavior inporous media. Our objective is to evaluate through numerical simulationthe importance of employing kinetic versus equilibrium reaction modelsfor predicting the response of hydrate-bearing systems to externalstimuli, such as changes in pressure and temperature. Specifically, we(1) analyze and compare the responses simulated using both reactionmodels for natural gas production from hydrates in various settings andfor the case of depressurization in a hydrate-bearing core duringextraction; and (2) examine the sensitivity to factors such as initialhydrate saturation, hydrate reaction surface area, and numericaldiscretization. We find that for large-scale systems undergoing thermalstimulation and depressurization, the calculated responses for bothreaction models are remarkably similar, though some differences areobserved at early times. However, for modeling short-term processes, suchas the rapid recovery of a hydrate-bearing core, kinetic limitations canbe important, and neglecting them may lead to significantunder-prediction of recoverable hydrate. The use of the equilibriumreaction model often appears to be justified and preferred for simulatingthe behavior of gas hydrates, given that the computational demands forthe kinetic reaction model far exceed those for the equilibrium reactionmodel.
Date: November 29, 2006
Creator: Kowalsky, Michael B. & Moridis, George J.
Object Type: Article
System: The UNT Digital Library
Comparison of kinetic and equilibrium reaction models insimulating the behavior of porous media (open access)

Comparison of kinetic and equilibrium reaction models insimulating the behavior of porous media

In this study we compare the use of kinetic and equilibriumreaction models in the simulation of gas (methane) hydrate behavior inporous media. Our objective is to evaluate through numerical simulationthe importance of employing kinetic versus equilibrium reaction modelsfor predicting the response of hydrate-bearing systems to externalstimuli, such as changes in pressure and temperature. Specifically, we(1) analyze and compare the responses simulated using both reactionmodels for natural gas production from hydrates in various settings andfor the case of depressurization in a hydrate-bearing core duringextraction; and (2) examine the sensitivity to factors such as initialhydrate saturation, hydrate reaction surface area, and numericaldiscretization. We find that for large-scale systems undergoing thermalstimulation and depressurization, the calculated responses for bothreaction models are remarkably similar, though some differences areobserved at early times. However, for modeling short-term processes, suchas the rapid recovery of a hydrate-bearing core, kinetic limitations canbe important, and neglecting them may lead to significantunder-prediction of recoverable hydrate. Assuming validity of the mostaccurate kinetic reaction model that is currently available, the use ofthe equilibrium reaction model often appears to be justified andpreferred for simulating the behavior of gas hydrates, given that thecomputational demands for the kinetic reaction model far exceed those forthe equilibrium reaction model.
Date: November 29, 2006
Creator: Kowalsky, Michael B. & Moridis, George J.
Object Type: Article
System: The UNT Digital Library
Greensheet (Houston, Tex.), Vol. 37, No. 510, Ed. 1 Wednesday, November 29, 2006 (open access)

Greensheet (Houston, Tex.), Vol. 37, No. 510, Ed. 1 Wednesday, November 29, 2006

Free weekly newspaper that includes business and classified advertising.
Date: November 29, 2006
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Cherokeean Herald (Rusk, Tex.), Vol. 157, No. 41, Ed. 1 Wednesday, November 29, 2006 (open access)

Cherokeean Herald (Rusk, Tex.), Vol. 157, No. 41, Ed. 1 Wednesday, November 29, 2006

Weekly newspaper from Rusk, Texas that includes local, state and national news along with extensive advertising.
Date: November 29, 2006
Creator: Whitehead, Marie
Object Type: Newspaper
System: The Portal to Texas History
North Texas Daily (Denton, Tex.), Vol. 91, No. 51, Ed. 1 Wednesday, November 29, 2006 (open access)

North Texas Daily (Denton, Tex.), Vol. 91, No. 51, Ed. 1 Wednesday, November 29, 2006

Daily student newspaper from the University of North Texas in Denton, Texas that includes local, state and campus news along with advertising.
Date: November 29, 2006
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
The Greensheet (Dallas, Tex.), Vol. 30, No. 232, Ed. 1 Wednesday, November 29, 2006 (open access)

The Greensheet (Dallas, Tex.), Vol. 30, No. 232, Ed. 1 Wednesday, November 29, 2006

Free weekly newspaper that includes business and classified advertising.
Date: November 29, 2006
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Greensheet (Houston, Tex.), Vol. 37, No. 509, Ed. 1 Wednesday, November 29, 2006 (open access)

Greensheet (Houston, Tex.), Vol. 37, No. 509, Ed. 1 Wednesday, November 29, 2006

Free weekly newspaper that includes business and classified advertising.
Date: November 29, 2006
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
A Cassette Based System for Hydrogen Storage and Delivery (open access)

A Cassette Based System for Hydrogen Storage and Delivery

A hydrogen storage system is described and evaluated. This is based upon a cassette, that is a container for managing hydrogen storage materials. The container is designed to be safe, modular, adaptable to different chemistries, inexpensive, and transportable. A second module receives the cassette and provides the necessary infrastructure to deliver hydrogen from the cassette according to enduser requirements. The modular concept has a number of advantages over approaches that are all in one stand alone systems. The advantages of a cassette based system are discussed, along with results from model and laboratory testing.
Date: November 29, 2006
Creator: E., Britton Wayne
Object Type: Report
System: The UNT Digital Library
IN SITU URANIUM STABILIZATION BY MICROBIAL METABOLITES (open access)

IN SITU URANIUM STABILIZATION BY MICROBIAL METABOLITES

Soil contaminated with U was the focus of this study in order to develop in-situ, U bio-immobilization technology. We have demonstrated microbial production of a metal chelating biopolymer, pyomelanin, in U contaminated soil from the Tims Branch area of the Department of Energy (DOE) Savannah River Site (SRS) as a result of tyrosine amendments. Bacterial densities of pyomelanin producers were >106 cells/g wet soil. Pyomelanin demonstrated U chelating and mineral binding capacities at pH 4 and 7. In laboratory studies, in the presence of goethite or illite, pyomelanin enhanced U sequestration by these minerals. Tyrosine amended soils in field tests demonstrated increased U sequestration capacity following pyomelanin production up to 13 months after tyrosine treatments.
Date: November 29, 2006
Creator: Turick, C; Anna Knox, A; Chad L Leverette,C & Yianne Kritzas, Y
Object Type: Article
System: The UNT Digital Library
Medical and Biohazardous Waste Generator's Guide (Revision2) (open access)

Medical and Biohazardous Waste Generator's Guide (Revision2)

These guidelines describe procedures to comply with all Federal and State laws and regulations and Lawrence Berkeley National Laboratory (LBNL) policy applicable to State-regulated medical and unregulated, but biohazardous, waste (medical/biohazardous waste). These guidelines apply to all LBNL personnel who: (1) generate and/or store medical/biohazardous waste, (2) supervise personnel who generate medical/biohazardous waste, or (3) manage a medical/biohazardous waste pickup location. Personnel generating biohazardous waste at the Joint Genome Institute/Production Genomics Facility (JGI/PGF) are referred to the guidelines contained in Section 9. Section 9 is the only part of these guidelines that apply to JGI/PGF. Medical/biohazardous waste referred to in this Web site includes biohazardous, sharps, pathological and liquid waste. Procedures for proper storage and disposal are summarized in the Solid Medical/Biohazardous Waste Disposal Procedures Chart. Contact the Waste Management Group at 486-7663 if you have any questions regarding medical/biohazardous waste management.
Date: November 29, 2006
Creator: Group, Waste Management
Object Type: Report
System: The UNT Digital Library
Central Energy System Modernization at Fort Jackson, South Carolina (open access)

Central Energy System Modernization at Fort Jackson, South Carolina

An evaluation of technology options was conducted for the central energy systems at Fort Jackson, South Carolina. There were two objectives in conducting this study. From a broader viewpoint, the Army would like to develop a systematic approach to management of its central energy systems and selected Fort Jackson for this ''pilot'' study for a prospective Central Energy System Modernization Program. From a site-specific perspective, the objective was to identify the lowest life-cycle cost energy supply option(s) at Fort Jackson for buildings currently served by central boilers and chillers. This study was co-funded by the Army's Southeast Region and the U.S. Department of Energy's Federal Energy Management Program.
Date: November 29, 2006
Creator: Brown, Daryl R.; Chvala, William D. & Dirks, James A.
Object Type: Report
System: The UNT Digital Library
Reduction of Large Detailed Chemical Kinetic Mechanisms for Autoignition Using Joint Analyses of Reaction Rates and Sensitivities (open access)

Reduction of Large Detailed Chemical Kinetic Mechanisms for Autoignition Using Joint Analyses of Reaction Rates and Sensitivities

A new technique of reduction of detailed mechanisms for autoignition, which is based on two analysis methods is described. An analysis of reaction rates is coupled to an analysis of reaction sensitivity for the detection of redundant reactions. Thresholds associated with the two analyses have a great influence on the size and efficiency of the reduced mechanism. Rules of selection of the thresholds are defined. The reduction technique has been successfully applied to detailed autoignition mechanisms of two reference hydrocarbons: n-heptane and iso-octane. The efficiency of the technique and the ability of the reduced mechanisms to reproduce well the results generated by the full mechanism are discussed. A speedup of calculations by a factor of 5.9 for n-heptane mechanism and by a factor of 16.7 for iso-octane mechanism is obtained without losing accuracy of the prediction of autoignition delay times and concentrations of intermediate species.
Date: November 29, 2006
Creator: Saylam, A; Ribaucour, M; Pitz, W J & Minetti, R
Object Type: Article
System: The UNT Digital Library
High-Power Ka-Band Window and Resonant Ring (open access)

High-Power Ka-Band Window and Resonant Ring

A stand-alone 200 MW rf test station is needed for carrying out development of accelerator structures and components for a future high-gradient multi-TeV collider, such as CLIC. A high-power rf window is needed to isolate the test station from a structure element under test. This project aimed to develop such a window for use at a frequency in the range 30-35 GHz, and to also develop a high-power resonant ring for testing the window. During Phase I, successful conceptual designs were completed for the window and the resonant ring, and cold tests of each were carried out that confirmed the designs.
Date: November 29, 2006
Creator: Hirshfield, Jay L.
Object Type: Report
System: The UNT Digital Library
20-MW Magnicon for ILC (open access)

20-MW Magnicon for ILC

The 1.3 GHz RF power to drive ILC is now planned to be supplied by 600-1200, 10-MW peak power multi-beam klystrons. In this project, a conceptual design for 1.3 GHz magnicons with 20 MW peak power was developed as an alternative to the klystrons, with the possibility of cutting in half the numbers of high-power tubes and associated components. Design of a conventional magnicon is described, using TM110 modes in all cavities, as well as design of a modified magnicon with a TE111 mode output cavity. The latter has the advantage of much lower surface fields than the TM110 mode, with no loss of output power or electronic efficiency.
Date: November 29, 2006
Creator: Hirshfield, Jay L.
Object Type: Report
System: The UNT Digital Library
Separating Metallic Beryllium from Plutonium by Selective Dissolution with Ammonium Fluoride (open access)

Separating Metallic Beryllium from Plutonium by Selective Dissolution with Ammonium Fluoride

Plutonium metal is stabilized for long-term storage by calcining to produce PuO{sub 2}. However, if beryllium is present, the calcined product may have a high neutron dose rate because of the {sup 9}Be({alpha},n){sup 12}C reaction in the finely divided oxide mixture. (At LLNL, inadvertent calcining of a mixture of {approx}500 g Pu/50 g Be produced a neutron source of {approx}5 R/hr.) Therefore, for health physics reasons, we would like a convenient procedure to remove beryllium from plutonium with high selectivity. Two reagents, sodium hydroxide and ammonium fluoride, were considered for aqueous processing. Each reagent selectively dissolves beryllium, which can be separated from the insoluble plutonium by decanting/filtering operations followed by water washes to remove the excess reagent. The washed plutonium is calcined for storage; the beryllium and wash fractions are solidified for disposal.
Date: November 29, 2006
Creator: Torres, R A
Object Type: Report
System: The UNT Digital Library
Ultrafast Coherent Diffractive Imaging at FLASH (open access)

Ultrafast Coherent Diffractive Imaging at FLASH

Using the FLASH facility we have demonstrated high-resolution coherent diffractive imaging with single soft-X-ray free-electron laser pulses [1]. The intense focused FEL pulse gives a high resolution low-noise coherent diffraction pattern of an object before that object turns into a plasma and explodes. Our experiments are an important milestone in the development of single-particle diffractive imaging with future X-ray free-electron lasers [2, 3]. Our apparatus provides a new and unique tool at FLASH to perform imaging of biological specimens beyond conventional radiation damage resolution limits [2, 4] and to acquire images of ultrafast processes initiated by an FEL pulse or other laser pulse. Coherent diffractive imaging is an ideal method for high-resolution ultrafast imaging with an FEL. Since no optical element is required, the method can in principle be scaled to atomic resolution with short enough wavelength. Spatial and temporal coherence are necessary to ensure that the scattered light waves from all positions across the sample are correlated when they interfere at the detector, giving rise to a coherent diffraction pattern that can be phased and inverted to give a high-resolution image of the sample. In contrast to crystals, where scattering from the many unit cells constructively interfere to give …
Date: November 29, 2006
Creator: Chapman, H N
Object Type: Report
System: The UNT Digital Library
The Wylie News (Wylie, Tex.), Vol. 59, No. 28, Ed. 1 Wednesday, November 29, 2006 (open access)

The Wylie News (Wylie, Tex.), Vol. 59, No. 28, Ed. 1 Wednesday, November 29, 2006

Weekly newspaper from Wylie, Texas that includes local, state and national news along with advertising.
Date: November 29, 2006
Creator: Engbrock, Chad B.
Object Type: Newspaper
System: The Portal to Texas History
Seminole Sentinel (Seminole, Tex.), Vol. 98, No. 15, Ed. 1 Wednesday, November 29, 2006 (open access)

Seminole Sentinel (Seminole, Tex.), Vol. 98, No. 15, Ed. 1 Wednesday, November 29, 2006

Semiweekly newspaper from Seminole, Texas that includes local, state, and national news along with extensive advertising.
Date: November 29, 2006
Creator: Wright, Dustin
Object Type: Newspaper
System: The Portal to Texas History
Yoakum Herald-Times (Yoakum, Tex.), Vol. 114, No. 48, Ed. 1 Wednesday, November 29, 2006 (open access)

Yoakum Herald-Times (Yoakum, Tex.), Vol. 114, No. 48, Ed. 1 Wednesday, November 29, 2006

Weekly newspaper from Yoakum, Texas that includes local, state, and national news along with advertising.
Date: November 29, 2006
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
The Clifton Record (Clifton, Tex.), Vol. 111, No. 48, Ed. 1 Wednesday, November 29, 2006 (open access)

The Clifton Record (Clifton, Tex.), Vol. 111, No. 48, Ed. 1 Wednesday, November 29, 2006

Weekly newspaper from Clifton, Texas that includes local, state, and national news along with advertising.
Date: November 29, 2006
Creator: Smith, W. Leon
Object Type: Newspaper
System: The Portal to Texas History

Oral History Interview with Cassandra F. Berry, November 29, 2006

Access: Use of this item is restricted to the UNT Community
Interview with Denton resident Cassandra F. Berry, UNT employee with a personal interest in the history of Quakertown, as part of the Quakertown Oral History Project. The interview includes Berry's personal experiences about working at UNT as the Associate Vice President for Equity and Diversity, as well as her service to the Denton African American Museum, which led to her interest in the history of Quakertown.
Date: November 29, 2006
Creator: Yancey, Sherelyn & Berry, Cassandra F.
Object Type: Book
System: The UNT Digital Library