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Computing Path Tables for Quickest Multipaths In Computer Networks (open access)

Computing Path Tables for Quickest Multipaths In Computer Networks

We consider the transmission of a message from a source node to a terminal node in a network with n nodes and m links where the message is divided into parts and each part is transmitted over a different path in a set of paths from the source node to the terminal node. Here each link is characterized by a bandwidth and delay. The set of paths together with their transmission rates used for the message is referred to as a multipath. We present two algorithms that produce a minimum-end-to-end message delay multipath path table that, for every message length, specifies a multipath that will achieve the minimum end-to-end delay. The algorithms also generate a function that maps the minimum end-to-end message delay to the message length. The time complexities of the algorithms are O(n{sup 2}((n{sup 2}/logn) + m)min(D{sub max}, C{sub max})) and O(nm(C{sub max} + nmin(D{sub max}, C{sub max}))) when the link delays and bandwidths are non-negative integers. Here D{sub max} and C{sub max} are respectively the maximum link delay and maximum link bandwidth and C{sub max} and D{sub max} are greater than zero.
Date: December 21, 2004
Creator: Grimmell, W.C.
Object Type: Report
System: The UNT Digital Library
Community Land Model Version 3.0 (CLM3.0) Developer's Guide (open access)

Community Land Model Version 3.0 (CLM3.0) Developer's Guide

This document describes the guidelines adopted for software development of the Community Land Model (CLM) and serves as a reference to the entire code base of the released version of the model. The version of the code described here is Version 3.0 which was released in the summer of 2004. This document, the Community Land Model Version 3.0 (CLM3.0) User's Guide (Vertenstein et al., 2004), the Technical Description of the Community Land Model (CLM) (Oleson et al., 2004), and the Community Land Model's Dynamic Global Vegetation Model (CLM-DGVM): Technical Description and User's Guide (Levis et al., 2004) provide the developer, user, or researcher with details of implementation, instructions for using the model, a scientific description of the model, and a scientific description of the Dynamic Global Vegetation Model integrated with CLM respectively. The CLM is a single column (snow-soil-vegetation) biogeophysical model of the land surface which can be run serially (on a laptop or personal computer) or in parallel (using distributed or shared memory processors or both) on both vector and scalar computer architectures. Written in Fortran 90, CLM can be run offline (i.e., run in isolation using stored atmospheric forcing data), coupled to an atmospheric model (e.g., the Community …
Date: December 21, 2004
Creator: Hoffman, FM
Object Type: Report
System: The UNT Digital Library
WIPP Subsidence Monument Leveling Survey - 2004 (open access)

WIPP Subsidence Monument Leveling Survey - 2004

Sections 2 through 7 of this report define the result of the 2004 leveling survey through the subsidence monuments at the WIPP site. Approximately 15 miles of leveling was completed through nine vertical control loops. The 2004 survey includes the determination of elevation on each of the 48 existing subsidence monuments and the WIPP baseline survey, and 14 of the National Geodetic Survey's (NGS) vertical control points. The field observations were completed during August through November of 2004 by personnel from the WashingtonTRU Solutions (WTS) Surveying Group, Mine Engineering Department. Additional rod personnel were provided by the Geotechnical Engineering department. Digital leveling techniques were utilized to achieve better than Second Order Class II loop closures as outlined by the Federal Geodetic Control Subcommittee (FGCS). Because it is important to perform the subsidence survey in exactly the same manner each year, WIPP procedure (WP 09-ES4001) details each step of the survey. Starting with the 2002 survey this procedure has been used to perform the subsidence survey. Starting with the survey of the year 2001, Loop 1 and redundant survey connections among the various loops were removed from the survey and report. This resulted in a reduction of fieldwork with no loss …
Date: December 21, 2004
Creator: Westinghouse TRU Solutions LLC
Object Type: Report
System: The UNT Digital Library
Impacts of Stable Element Intake on C and I Dose Estimates - Implications for Proposed Yucca Mountain Repository (open access)

Impacts of Stable Element Intake on C and I Dose Estimates - Implications for Proposed Yucca Mountain Repository

The purpose of this study was to evaluate the influence of the intake of stable isotopes of carbon and iodine on the committed doses due to the ingestion of {sup 14}C and {sup 129}I. This was accomplished through the application of two different computational approaches. The first was based on the assumption that ground (drinking) water was the only source of intake of both {sup 14}C and {sup 129}I and stable carbon and stable iodine. For purposes of the second approach, the intake of {sup 14}C and {sup 129}I was still assumed to be only that in the ground (drinking) water, but the intake of stable carbon and stable iodine was assumed to be that in the drinking water plus other components of the diet. The doses were estimated using either a conversion formula or the applicable dose coefficients in Federal Guidance Reports No. 11 and No. 13. Serving as input for the analyses was the estimated maximum concentration of {sup 14}C or {sup 129}I that would be present in the ground water due to potential releases from the proposed Yucca Mountain high-level radioactive waste repository during the first 10,000 years after closure. The estimated concentrations of stable carbon and …
Date: December 21, 2004
Creator: Moeller, Dade W.; Ryan, Michael T.; Sun, Lin-Shen C. & Cherry, Robert N., Jr.
Object Type: Report
System: The UNT Digital Library
Comparison of Four Parallel Algorithms For Domain Decomposed Implicit Monte Carlo (open access)

Comparison of Four Parallel Algorithms For Domain Decomposed Implicit Monte Carlo

We consider two existing asynchronous parallel algorithms for Implicit Monte Carlo (IMC) thermal radiation transport on spatially decomposed meshes. The two algorithms are from the production codes KULL from Lawrence Livermore National Laboratory and Milagro from Los Alamos National Laboratory. Both algorithms were considered and analyzed in an implementation of the KULL IMC package in ALEGRA, a Sandia National Laboratory high energy density physics code. Improvements were made to both algorithms. The improved Milagro algorithm performed the best by scaling nearly perfectly out to 244 processors.
Date: December 21, 2004
Creator: Brunner, T A; Urbatsch, T J; Evans, T M & Gentile, N A
Object Type: Article
System: The UNT Digital Library
Rains County Leader (Emory, Tex.), Vol. 117, No. 28, Ed. 1 Tuesday, December 21, 2004 (open access)

Rains County Leader (Emory, Tex.), Vol. 117, No. 28, Ed. 1 Tuesday, December 21, 2004

Weekly newspaper from Emory, Texas that includes local, state, and national news along with advertising.
Date: December 21, 2004
Creator: Hill, Earl Clyde, Jr.
Object Type: Newspaper
System: The Portal to Texas History
Numerical and Physical Modelling of Bubbly Flow Phenomena - Final Report to the Department of Energy (open access)

Numerical and Physical Modelling of Bubbly Flow Phenomena - Final Report to the Department of Energy

This report describes the main features of the results obtained in the course of this project. A new approach to the systematic development of closure relations for the averaged equations of disperse multiphase flow is outlined. The focus of the project is on spatially non-uniform systems and several aspects in which such systems differ from uniform ones are described. Then, the procedure used in deriving the closure relations is given and some explicit results shown. The report also contains a list of publications supported by this grant and a list of the persons involved in the work.
Date: December 21, 2004
Creator: Prosperetti, Andrea
Object Type: Report
System: The UNT Digital Library
COST EFFECTIVE REGULATORY APPROACHES TO ENHANCE DOMESTIC OIL & GAS PRODUCTION AND ENSURE THE PROTECTION OF THE ENVIRONMENT (open access)

COST EFFECTIVE REGULATORY APPROACHES TO ENHANCE DOMESTIC OIL & GAS PRODUCTION AND ENSURE THE PROTECTION OF THE ENVIRONMENT

The Environmental Information Management Suite/Risk Based Data Management System (EIMS/RBDMS) and Cost Effective Regulatory Approach (CERA) programs continue to be successful. All oil and gas state regulatory programs participate in these efforts. Significant accomplishments include: streamline regulatory approaches, enhancing environmental protection, and making oil and gas data available via the Internet. Oil and gas companies worldwide now have access to data on state web sites. This reduces the cost of exploration and enables companies to develop properties in areas that would have been cost prohibited for exploration. Early in project, GWPC and State Oil and Gas agencies developed the EIMS and CERA strategic plan to prioritize long term development and implementation. The planning process identifies electronic commerce and coal bed methane as high priorities. The group has involved strategic partners in industry and government to develop a common data exchange process. Technical assistance to Alaska continues to improve their program management capabilities. New initiatives in Alaska include the development of an electronic permit tracking system. This system allows managers to expedite the permitting process. Nationwide, the RBDMS system is largely completed with 22 states and one Indian Nation now using this nationally accepted data management system. Additional remaining tasks include …
Date: December 21, 2004
Creator: Grunewald, Ben; Jehn, Paul; Gillespie, Tom & Binder, Ben
Object Type: Report
System: The UNT Digital Library
Results for the DWPF Slurry Mix Evaporator Condensate Tank, Off Gas Condensate Tank, And Recycle Collection Tank Samples (open access)

Results for the DWPF Slurry Mix Evaporator Condensate Tank, Off Gas Condensate Tank, And Recycle Collection Tank Samples

The Defense Waste Processing Facility, DWPF, currently generates approximately 1.4 million gallons of recycle water per year during Sludge-Only operations. DWPF has minimized condensate generation to 1.4 million gallons by not operating the Steam Atomized Scrubbers, SASs, for the melter off gas system. By not operating the SASs, DWPF has reduced the total volume by approximately 800,000 gallons of condensate per year. Currently, the recycle stream is sent to back to the Tank Farm and processed through the 2H Evaporator system. To alleviate the load on the 2H Evaporator system, an acid evaporator design is being considered as an alternate processing and/or concentration method for the DWPF recycle stream. In order to support this alternate processing option, the DWPF has requested that the chemical and radionuclide compositions of the Off Gas Condensate Tank, OGCT, Slurry Mix Evaporator Condensate Tank, SMECT, Recycle Collection Tank, RCT, and the Decontamination Waste Treatment Tank, DWTT, be determined as a part of the process development work for the acid evaporator design. Samples have been retrieved from the OGCT, RCT, and SMECT and have been sent to the Savannah River National Laboratory, SRNL for this characterization. The DWTT samples have been recently shipped to SRNL. The …
Date: December 21, 2004
Creator: TERRI, FELLINGER
Object Type: Report
System: The UNT Digital Library
Quantized Eigenstates of a Classical Particle in a Ponderomotive Potential (open access)

Quantized Eigenstates of a Classical Particle in a Ponderomotive Potential

The average dynamics of a classical particle under the action of a high-frequency radiation resembles quantum particle motion in a conservative field with an effective de Broglie wavelength ë equal to the particle average displacement on a period of oscillations. In a "quasi-classical" field, with a spatial scale large compared to ë, the guiding center motion is adiabatic. Otherwise, a particle exhibits quantized eigenstates in a ponderomotive potential well, can tunnel through classically forbidden regions and experience reflection from an attractive potential. Discrete energy levels are also found for a "crystal" formed by multiple ponderomotive barriers.
Date: December 21, 2004
Creator: Dodin, I. Y. & Fisch, N. J.
Object Type: Report
System: The UNT Digital Library
GaAs Blocked-Impurity-Band Detectors for Far-Infrared Astronomy (open access)

GaAs Blocked-Impurity-Band Detectors for Far-Infrared Astronomy

High-purity and doped GaAs films have been grown by Liquid-phase epitaxy (LPE) for development of a blocked impurity band (BIB) detector for far-infrared radiation. The film growth process developed has resulted in the capability to grow GaAs with a net active impurity concentration below 1 x 10{sup 13} cm{sup -3}, ideal for the blocking layer of the BIB detector. The growth of n-type LPE GaAs films with donor concentrations below the metal-insulator transition, as required for the absorbing layer of a BIB detector, has been achieved. The control of the donor concentration, however, was found to be insufficient for detector production. The growth by LPE of a high-purity film onto a commercially grown vapor-phase epitaxial (VPE) n-type GaAs doped absorbing layer resulted in a BIB device that showed a significant reduction in the low-temperature dark current compared to the absorbing layer only. Extended optical response was not detected, most likely due to the high compensation of the commercially grown GaAs absorbing layer, which restricts the depletion width of the device.
Date: December 21, 2004
Creator: Cardozo, Benjamin Lewin
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Gyrokinetic Studies of Turbulence in Steep Gradient Region: Role of Turbulence Spreading and E x B Shear (open access)

Gyrokinetic Studies of Turbulence in Steep Gradient Region: Role of Turbulence Spreading and E x B Shear

An integrated program of gyrokinetic particle simulation and theory has been developed to investigate several outstanding issues in both turbulence and neoclassical physics. Gyrokinetic particle simulations of toroidal ion temperature gradient (ITG) turbulence spreading using the GTC code and its related dynamical model have been extended to the case with radially increasing ion temperature gradient, to study the inward spreading of edge turbulence toward the core. Due to turbulence spreading from the edge, the turbulence intensity in the core region is significantly enhanced over the value obtained from simulations of the core region only. Even when the core gradient is within the Dimits shift regime (i.e., self-generated zonal flows reduce the transport to a negligible value), a significant level of turbulence and transport is observed in the core due to spreading from the edge. The scaling of the turbulent front propagation speed is closer to the prediction from our nonlinear diffusion model than one based on linear toroidal coupling. A calculation of ion poloidal rotation in the presence of sharp density and toroidal angular rotation frequency gradients from the GTC-Neo particle simulation code shows that the results are significantly different from the conventional neoclassical theory predictions. An energy conserving set …
Date: December 21, 2004
Creator: Hahm, T. S.; Lin, Z.; Diamond, P. H.; Rewoldt, G.; Wang, W. X.; Ethier, S. et al.
Object Type: Report
System: The UNT Digital Library
Easing the natural gas crisis: Reducing natural gas prices through increased deployment of renewable energy and energy efficiency (open access)

Easing the natural gas crisis: Reducing natural gas prices through increased deployment of renewable energy and energy efficiency

Heightened natural gas prices have emerged as a key energy-policy challenge for at least the early part of the 21st century. With the recent run-up in gas prices and the expected continuation of volatile and high prices in the near future, a growing number of voices are calling for increased diversification of energy supplies. Proponents of renewable energy and energy efficiency identify these clean energy sources as an important part of the solution. Increased deployment of renewable energy (RE) and energy efficiency (EE) can hedge natural gas price risk in more than one way, but this paper touches on just one potential benefit: displacement of gas-fired electricity generation, which reduces natural gas demand and thus puts downward pressure on gas prices. Many recent modeling studies of increased RE and EE deployment have demonstrated that this ''secondary'' effect of lowering natural gas prices could be significant; as a result, this effect is increasingly cited as justification for policies promoting RE and EE. This paper summarizes recent studies that have evaluated the gas-price-reduction effect of RE and EE deployment, analyzes the results of these studies in light of economic theory and other research, reviews the reasonableness of the effect as portrayed in …
Date: December 21, 2004
Creator: Wiser, Ryan; Bolinger, Mark & St. Clair, Matt
Object Type: Report
System: The UNT Digital Library
Cascades from nu_E above 1020 eV (open access)

Cascades from nu_E above 1020 eV

At very high energies, the Landau-Pomeranchuk-Migdal effect reduces the cross sections for electron bremsstrahlung and photon e{sup +}e{sup -} pair production. The fractional electron energy loss and pair production cross sections drop as the energy increases. In contrast, the cross sections for photonuclear interactions grow with energy. In solids and liquids, at energies above 10{sup 20} eV, photonuclear reactions dominate, and showers that originate as photons or electrons quickly become hadronic showers. These electron-initiated hadronic showers are much shorter (due to the absence of the LPM effect), but wider than purely electromagnetic showers would be. This change in shape alters the spectrum of the electromagnetic and acoustic radiation emitted from the shower. These alterations have important implications for existing and planned searches for radiation from u{sub e} induced showers above 10{sup 20} eV, and some existing limits should be reevaluated.
Date: December 21, 2004
Creator: Klein, Spencer R.
Object Type: Article
System: The UNT Digital Library
Final Technical Report for DOE Grant DE-FG03-7ER54438 (open access)

Final Technical Report for DOE Grant DE-FG03-7ER54438

Laboratory experiments using technology developed for fusion research created replicas of solar prominences. These solar coronal loops exhibited dynamic behavior similar to what is observed on the sun. Diagnostics included high-speed photography, and x-ray detectors. In addition to the experiments, two related theoretical investigations were undertaken: (1) a three-dimensional numerical model of coronal mass ejections, and (2) a model of the plasma jet flow and collimation resulting from an electric current flowing along a magnetic flux tube.
Date: December 21, 2004
Creator: P.M.Bellan
Object Type: Report
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 84, No. 16, Ed. 1 Tuesday, December 21, 2004 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 84, No. 16, Ed. 1 Tuesday, December 21, 2004

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: December 21, 2004
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
Conversion and optimization of the parameters from an extended form of the ion-interaction model for Ca(NO3)2(aq) and NaNO3(aq) to those of the standard Pitzer model, and an assessment of the accuracy of the parameter temperature representations (open access)

Conversion and optimization of the parameters from an extended form of the ion-interaction model for Ca(NO3)2(aq) and NaNO3(aq) to those of the standard Pitzer model, and an assessment of the accuracy of the parameter temperature representations

The electrolytes Ca(NO{sub 3}){sub 2}(aq) and NaNO{sub 3}(aq) are both extremely soluble but differ in several important respects. Ca(NO{sub 3}){sub 2}(aq) has complex behavior at low ionic strengths and forms several thermodynamically stable and metastable solid phases, whereas NaNO{sub 3}(aq) forms only an anhydrous solid phase. The thermodynamic properties of both have previously been modeled using extended Pitzer ion-interaction models that include higher-order virial terms, in addition to those of the standard Pitzer model. The parameters of the original Pitzer model, however, are often needed for thermodynamic modeling calculations. In this paper we convert the parameters of the extended ion-interaction models for Ca(NO{sub 3}){sub 2}(aq) and NaNO{sub 3}(aq) to the standard Pitzer model using an extension of the methodology previously described by Rard and Wijesinghe [J. Chem. Thermodynamics 35 (2003) 439.473]. In this variant, the exponential coefficient {alpha}{sub 1}{sup P} of Pitzer's model is also optimized to yield the most accurate overall representation of the osmotic coefficients {phi} over the ionic strength and temperature ranges of interest. The optimal values of {alpha}{sub 1}{sup P} = 0.87 kg{sup 1/2} {center_dot} mol{sup -1/2} for Ca(NO{sub 3}){sub 2}(aq) and {alpha}{sub 1}{sup P} = 1.43 kg{sup 1/2} {center_dot} mol{sup -1/2} for NaNO{sub 3}(aq) are …
Date: December 21, 2004
Creator: Wijesinghe, A M & Rard, J A
Object Type: Article
System: The UNT Digital Library
Appropriations for FY2005: Transportation, Treasury, and Independent Agencies (open access)

Appropriations for FY2005: Transportation, Treasury, and Independent Agencies

This report is a guide to one of the 13 regular appropriations bills that Congress considers each year. It summarizes the status of the bill, its scope, major issues, funding levels, and related congressional activity, and is updated as events warrant.
Date: December 21, 2004
Creator: Peterman, David Randall & Frittelli, John
Object Type: Report
System: The UNT Digital Library
Comparison of Four Parallel Algorithms For Domain Decomposed Implicit Monte Carlo (open access)

Comparison of Four Parallel Algorithms For Domain Decomposed Implicit Monte Carlo

Four different algorithms for domain decomposed Monte Carlo are outlined, and the performance of each is measured. These algorithms are implemented in the KULL IMC package [4] running inside of ALEGRA [1]. This package implements the Implicit Monte Carlo (IMC) scheme for thermal radiation transport of Fleck and Cummings [3].
Date: December 21, 2004
Creator: Brunner, T; Urbatsch, T; Evans, T & Gentile, N
Object Type: Article
System: The UNT Digital Library
Spyware: Background and Policy Issues for Congress (open access)

Spyware: Background and Policy Issues for Congress

None
Date: December 21, 2004
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Spent Nuclear Fuel Storage Locations and Inventory (open access)

Spent Nuclear Fuel Storage Locations and Inventory

None
Date: December 21, 2004
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Immigration-Related Document Fraud: Overview of Civil, Criminal, and Immigration Consequences (open access)

Immigration-Related Document Fraud: Overview of Civil, Criminal, and Immigration Consequences

This report mainly discusses about the Overview of Civil, Criminal, and Immigration Consequences on Immigration-Related Document Fraud. It also discusses about the primary civil, criminal , and immigration related penalties associated with immigration related document fraud.
Date: December 21, 2004
Creator: Garcia, Michael John
Object Type: Report
System: The UNT Digital Library
9/11 Commission: Legislative Action Concerning U.S. Immigration Law and Policy in the 108th Congress (open access)

9/11 Commission: Legislative Action Concerning U.S. Immigration Law and Policy in the 108th Congress

From Summary: "This report discusses some of the major immigration areas that were under consideration in the above-mentioned comprehensive reform proposals, including asylum, biometric tracking systems, border security, document security, exclusion, immigration enforcement, and visa issuances."
Date: December 21, 2004
Creator: Garcia, Michael John & Wasem, Ruth Ellen
Object Type: Report
System: The UNT Digital Library
An Evaluation of UDP Transport Protocols (open access)

An Evaluation of UDP Transport Protocols

Although the speed of LAN and WAN networking is growing at an exponential rate, the applications that use those networks have not followed suit. With fiber optic interconnects, gigahertz processor speeds, and 10 gigabit per second network interface cards, hardware does not seem to be the limiting factor. It is becoming increasingly obvious that the protocols that are the basis of networking today are ill-suited to a new generation of networking technology. For this reason, Oak Ridge National Laboratory is particularly interested in improving bulk transfers over high-bandwidth, high-latency networks because of its involvement in storage and in the transfer of data for cutting-edge scientific applications. This report summarizes our evaluation of a new group of protocols specifically designed to get more useful bandwidth from today's high speed, wide area networks.
Date: December 21, 2004
Creator: Carter, S
Object Type: Report
System: The UNT Digital Library