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Analyses of Wind Energy Impact on WFEC System Operations: Preprint (open access)

Analyses of Wind Energy Impact on WFEC System Operations: Preprint

The National Renewable Energy Laboratory worked with the Western Farmers Electric Cooperative to analyze the impact of wind power from the Blue Canyon Wind Power Project on WFEC system operations.
Date: March 1, 2006
Creator: Wan, Y. & Liao, J. R.
System: The UNT Digital Library
Analysis of the causes of failure in high chrome oxide refractory materials from slagging gasifiers (open access)

Analysis of the causes of failure in high chrome oxide refractory materials from slagging gasifiers

High Cr2O3 refractory materials are used to line the hot face of slagging gasifiers. Gasifiers are reaction chambers that convert water, oxygen, and a carbon feedstock into CO, H2, and methane at temperatures as high as 1575oC and pressures up to 1000 psi. Ash in the carbon feedstock liquefies, erodes and corrodes the gasifier’s refractory liner, contributing to liner failure within a few months to two years. The failure of a refractory liner decreases a gasifier’s on-line availability and causes costly system downtime and repairs. Many factors contribute to refractory lining failure, including slag penetration and corrosion, thermal cycling, gasifier environment, and mechanical loads. The results of refractory post-mortem failure analysis and how observations relate to gasifier service life will be discussed.
Date: March 1, 2006
Creator: Bennett, J. P.; Kwong, K. -S.; Powell, C. A.; Thomas, H. & Krabbe, R. A.
System: The UNT Digital Library
The application of Tiny Triplet Finder (TTF) in BTeV pixel trigger (open access)

The application of Tiny Triplet Finder (TTF) in BTeV pixel trigger

We describe a track segment recognition scheme called the Tiny Triplet Finder (TTF) that involves grouping of three hits satisfying a constraint such as forming of a straight line. The TTF performs this O(n{sup 3}) function in O(n) time, where n is number of hits in each detector plane. The word ''tiny'' reflects the fact that the FPGA resource usage is small. The number of logic elements needed for the TTF is O(Nlog(N)), where N is the number of bins in the coordinate considered, which for large N, is significantly smaller than O(N{sup 2}) needed for typical implementations of similar functions. The TTF is also suitable for software implementations as well as many other pattern recognition problems.
Date: March 1, 2006
Creator: Wu, Jin-Yuan; Wang, M.; Gottschalk, E. & Shi, Z.
System: The UNT Digital Library
Applications of barrier bucket RF systems at Fermilab (open access)

Applications of barrier bucket RF systems at Fermilab

In recent years, the barrier rf systems have become important tools in a variety of beam manipulation applications at synchrotrons. Four out of six proton synchrotrons at Fermilab are equipped with broad-band barrier rf systems. All of the beam manipulations pertaining to the longitudinal phase space in the Fermilab Recycler (synchrotron used for antiproton storage) are carried out using a barrier system. Recently, a number of new applications of barrier rf systems have been developed- the longitudinal momentum mining, longitudinal phase-space coating, antiproton stacking, fast bunch compression and more. Some of these techniques have been critical for the recent spectacular success of the collider performance at the Fermilab Tevatron. Barrier bunch coalescing to produce bright proton bunches has a high potential to increase proton antiproton luminosity significantly. In this paper, I will describe some of these techniques in detail. Finally, I make a few general remarks on issues related to barrier systems.
Date: March 1, 2006
Creator: Bhat, C.M.
System: The UNT Digital Library
Challenges in Detecting Gamma-Rays From Dark Matter Annihilations in the Galactic Center (open access)

Challenges in Detecting Gamma-Rays From Dark Matter Annihilations in the Galactic Center

None
Date: March 1, 2006
Creator: Zaharijas, Gabrijela & Hooper, Dan
System: The UNT Digital Library
Charm quark contribution to K+ ---> pi+ nu anti-nu at next-to-next-to-leading order (open access)

Charm quark contribution to K+ ---> pi+ nu anti-nu at next-to-next-to-leading order

The authors calculate the complete next-to-next-to-leading order QCD corrections to the charm contribution of the rare decay K{sup +} {yields} {pi}{sup +}{nu}{bar {nu}}. They encounter several new features, which were absent in lower orders. They discuss them in detail and present the results for the two-loop matching conditions of the Wilson coefficients, the three-loop anomalous dimensions, and the two-loop matrix elements of the relevant operators that enter the next-to-next-to-leading order renormalization group analysis of the Z-penguin and the electroweak box contribution. The inclusion of the next-to-next-to-leading order QCD corrections leads to a significant reduction of the theoretical uncertainty from {+-} 9.8% down to {+-} 2.4% in the relevant parameter P{sub c}(X), implying the leftover scale uncertainties in {Beta}(K{sup +} {yields} {pi}{sup +}{nu}{bar {nu}}) and in the determination of |V{sub td}|, sin 2{beta}, and {gamma} from the K {yields} {pi}{nu}{bar {nu}} system to be {+-} 1.3%, {+-} 1.0%, {+-} 0.006, and {+-} 1.2{sup o}, respectively. For the charm quark {ovr MS} mass m{sub c}(m{sub c}) = (1.30 {+-} 0.05) GeV and |V{sub us}| = 0.2248 the next-to-leading order value P{sub c}(X) = 0.37 {+-} 0.06 is modified to P{sub c}(X) = 0.38 {+-} 0.04 at the next-to-next-to-leading order level with the …
Date: March 1, 2006
Creator: Buras, Andrzej J.; Gorbahn, Martin; Haisch, Ulrich & Nierste, Ulrich
System: The UNT Digital Library
Comparative Genome Analysis in the Integrated Microbial Genomes (IMG) System (open access)

Comparative Genome Analysis in the Integrated Microbial Genomes (IMG) System

Comparative genome analysis is critical for the effectiveexploration of a rapidly growing number of complete and draft sequencesfor microbial genomes. The Integrated Microbial Genomes (IMG) system(img.jgi.doe.gov) has been developed as a community resource thatprovides support for comparative analysis of microbial genomes in anintegrated context. IMG allows users to navigate the multidimensionalmicrobial genome data space and focus their analysis on a subset ofgenes, genomes, and functions of interest. IMG provides graphicalviewers, summaries and occurrence profile tools for comparing genes,pathways and functions (terms) across specific genomes. Genes can befurther examined using gene neighborhoods and compared with sequencealignment tools.
Date: March 1, 2006
Creator: Kyrpides, Nikos C. & Markowitz, Victor M.
System: The UNT Digital Library
Comparing Single and Multiple Turbine Representations in a Wind Farm Simulation: Preprint (open access)

Comparing Single and Multiple Turbine Representations in a Wind Farm Simulation: Preprint

This paper compares single turbine representation versus multiple turbine representation in a wind farm simulation.
Date: March 1, 2006
Creator: Muljadi, E. & Parsons, B.
System: The UNT Digital Library
Comparing the Usefulness of Video and Map Information In Navigation Tasks (open access)

Comparing the Usefulness of Video and Map Information In Navigation Tasks

One of the fundamental aspects of robot teleoperation is the ability to successfully navigate a robot through an environment. We define successful navigation to mean that the robot minimizes collisions and arrives at the destination in a timely manner. Often video and map information is presented to a robot operator to aid in navigation tasks. This paper addresses the usefulness of map and video information in a navigation task by comparing a side-by-side (2D) representation and an integrated (3D) representation in both a simulated and a real world study. The results suggest that sometimes video is more helpful than a map and other times a map is more helpful than video. From a design perspective, an integrated representation seems to help navigation more than placing map and video side-by-side.
Date: March 1, 2006
Creator: Nielsen, Curtis W. & Goodrich, Michael A.
System: The UNT Digital Library
Comparison of Cleaning Methods for Analysis of Underground Beryllium Corrosion (open access)

Comparison of Cleaning Methods for Analysis of Underground Beryllium Corrosion

The subsurface radioactive disposal site located at the Idaho National Laboratory contains neutronactivated beryllium metals from non-fuel nuclear-reactor-core components. A long-term underground corrosion test is being conducted to obtain site-specific corrosion rates of the disposed beryllium to support efforts to more accurately estimate the transfer of activated elements in the surrounding arid vadose zone environment. During the corrosion analysis, two cleaning methods were used. This paper describes the cleaning methods and presents a comparison of the results.
Date: March 1, 2006
Creator: Flitton, M. K. Adler & Yoder, T. S.
System: The UNT Digital Library
Constraints on B and Higgs physics in minimal low energy supersymmetric models (open access)

Constraints on B and Higgs physics in minimal low energy supersymmetric models

We study the implications of minimal flavor violating low energy supersymmetry scenarios for the search of new physics in the B and Higgs sectors at the Tevatron collider and the LHC. We show that the already stringent Tevatron bound on the decay rate B{sub s} {yields} {mu}{sup +}{mu}{sup -} sets strong constraints on the possibility of generating large corrections to the mass difference {Delta} M{sub s} of the B{sub s} eigenstates. We also show that the B{sub s} {yields} {mu}{sup +}{mu}{sup -} bound together with the constraint on the branching ratio of the rare decay b {yields} s{gamma} has strong implications for the search of light, non-standard Higgs bosons at hadron colliders. In doing this, we demonstrate that the former expressions derived for the analysis of the double penguin contributions in the Kaon sector need to be corrected by additional terms for a realistic analysis of these effects. We also study a specific non-minimal flavor violating scenario, where there are flavor changing gluino-squark-quark interactions, governed by the CKM matrix elements, and show that the B and Higgs physics constraints are similar to the ones in the minimal flavor violating case. Finally we show that, in scenarios like electroweak baryogenesis which …
Date: March 1, 2006
Creator: Carena, Marcela; Menon, A.; Noriega-Papaqui, R.; Szynkman, A. & Wagner, C. E. M.
System: The UNT Digital Library
Controlled Hydrogen Fleet and Infrastructure Demonstration and Validation Project: Progress Update; Preprint (open access)

Controlled Hydrogen Fleet and Infrastructure Demonstration and Validation Project: Progress Update; Preprint

Summary of DOE's Controlled Hydrogen Fleet and Infrastructure Demonstration and Validation project from initiation through January 2006.
Date: March 1, 2006
Creator: Wipke, K.; Welch, C.; Thomas, H.; Sprik, S.; Gronich, S.; Garbak, J. et al.
System: The UNT Digital Library
Corrosion behavior of experimental and commercial nickel-base alloys in HCl and HCl containing Fe3+ (open access)

Corrosion behavior of experimental and commercial nickel-base alloys in HCl and HCl containing Fe3+

The effects of ferric ions on the corrosion resistance and electrochemical behavior of a series of Ni-based alloys in 20% HCl at 30ºC were investigated. The alloys studied were those prepared by the Albany Research Center (ARC), alloys J5, J12, J13, and those sold commercially, alloys 22, 242, 276, and 2000. Tests included mass loss, potentiodynamic polarization, and linear polarization.
Date: March 1, 2006
Creator: Holcomb, G. R.; Covino, B. S., Jr.; Bullard, S. J. & Ziomek-Moroz, M.
System: The UNT Digital Library
Corrosion behavior of iron and nickel base alloys under solid oxide fuel cell exposure conditions (open access)

Corrosion behavior of iron and nickel base alloys under solid oxide fuel cell exposure conditions

Topography and phase composition of the scales formed on commercial ferritic stainless steels and experimental low CTE nickel-based alloys were studied in atmospheres simulating solid oxide fuel cell (SOFC) environments. The materials were studied under dual environment conditions with air on one side of the sample and carbon monoxide on the other side at 750°C. Surface characterization techniques, such as scanning electron microscopy and X-ray diffraction analysis were used in this study.
Date: March 1, 2006
Creator: Ziomek-Moroz, M.; Holcomb, G. R.; Covino, B. S., Jr. & Bullard, S. J.
System: The UNT Digital Library
Coupled Dynamic Modeling of Floating Wind Turbine Systems: Preprint (open access)

Coupled Dynamic Modeling of Floating Wind Turbine Systems: Preprint

This article presents a collaborative research program that the Massachusetts Institute of Technology (MIT) and the National Renewable Energy Laboratory (NREL) have undertaken to develop innovative and cost-effective floating and mooring systems for offshore wind turbines in water depths of 10-200 m. Methods for the coupled structural, hydrodynamic, and aerodynamic analysis of floating wind turbine systems are presented in the frequency domain. This analysis was conducted by coupling the aerodynamics and structural dynamics code FAST [4] developed at NREL with the wave load and response simulation code WAMIT (Wave Analysis at MIT) [15] developed at MIT. Analysis tools were developed to consider coupled interactions between the wind turbine and the floating system. These include the gyroscopic loads of the wind turbine rotor on the tower and floater, the aerodynamic damping introduced by the wind turbine rotor, the hydrodynamic damping introduced by wave-body interactions, and the hydrodynamic forces caused by wave excitation. Analyses were conducted for two floater concepts coupled with the NREL 5-MW Offshore Baseline wind turbine in water depths of 10-200 m: the MIT/NREL Shallow Drafted Barge (SDB) and the MIT/NREL Tension Leg Platform (TLP). These concepts were chosen to represent two different methods of achieving stability to identify …
Date: March 1, 2006
Creator: Wayman, E. N.; Sclavounos, P. D.; Butterfield, S.; Jonkman, J. & Musial, W.
System: The UNT Digital Library
Current Comparison of Advanced Fuel Cycle Options (open access)

Current Comparison of Advanced Fuel Cycle Options

The nuclear fuel cycle includes mining, enrichment, nuclear power plants, recycling (if done), and residual waste disposition. The U.S. Advanced Fuel Cycle Initiative (AFCI) has four program objectives to guide research on how best to glue these pieces together, as follows: waste management, proliferation resistance, energy recovery, and systematic management/economics/safety. We have developed a comprehensive set of metrics to evaluate fuel cycle options against the four program objectives. The current list of metrics is long-term heat, long-term dose, radiotoxicity and weapons usable material. This paper describes the current metrics and initial results from comparisons made using these metrics. The data presented were developed using a combination of “static” calculations and a system dynamic model, DYMOND. In many cases, we examine the same issue both dynamically and statically to determine the robustness of the observations. All analyses are for the U.S. reactor fleet. This work aims to clarify many of the issues being discussed within the AFCI program, including Inert Matrix Fuel (IMF) versus Mixed Oxide (MOX) fuel, single-pass versus multi-pass recycling, thermal versus fast reactors, and the value of separating cesium and strontium. The results from a series of dynamic simulations evaluating these options are included in this report. The …
Date: March 1, 2006
Creator: Piet, Steven J.; Dixon, B. W.; Goldmann, A.; Hill, R. N.; Jacobson, J. J.; Matthern, G. E. et al.
System: The UNT Digital Library
Effect of Crevice Former on Corrosion Damage Propagation (open access)

Effect of Crevice Former on Corrosion Damage Propagation

The objectives of this report are: (1) To determine the effect of the crevice former on the localized corrosion damage propagation; (2) FOCUS on post initiation stage, crevice propagation and arrest processes; (3) Determine the evolution of damage--severity, shape, location/distribution, damage profile; and (4) Model of crevice corrosion propagation, i.e. the evolution of the crevice corrosion damage profile.
Date: March 1, 2006
Creator: Payer, J. H.; Landau, U.; Shan, X. & Agarwal, A. S.
System: The UNT Digital Library
Electrothermal Analysis of Lithium Ion Batteries (open access)

Electrothermal Analysis of Lithium Ion Batteries

This report presents the electrothermal analysis and testing of lithium ion battery performance. The objectives of this report are to: (1) develop an electrothermal process/model for predicting thermal performance of real battery cells and modules; and (2) use the electrothermal model to evaluate various designs to improve battery thermal performance.
Date: March 1, 2006
Creator: Pesaran, A.; Vlahinos, A.; Bharathan, D. & Duong, T.
System: The UNT Digital Library
Estimating design costs for first-of-a-kind projects (open access)

Estimating design costs for first-of-a-kind projects

Modern scientific facilities are often outcomes of projects that are first-of-a-kind, that is, minimal historical data are available for project costs and schedules. However, at Fermilab, there was an opportunity to execute two similar projects consecutively. In this paper, a comparative study of the design costs for these two projects is presented using earned value methodology. This study provides some insights into how to estimate the cost of a replicated project.
Date: March 1, 2006
Creator: Banerjee, Bakul
System: The UNT Digital Library
Evaluation Methodology for Proliferation Resistance and Physical Protection of Generation IV Nuclear Energy Systems: An Overview. (open access)

Evaluation Methodology for Proliferation Resistance and Physical Protection of Generation IV Nuclear Energy Systems: An Overview.

This paper provides an overview of the methodology approach developed by the Generation IV International Forum Expert Group on Proliferation Resistance & Physical Protection for evaluation of Proliferation Resistance and Physical Protection robustness of Generation IV nuclear energy systems options. The methodology considers a set of alternative systems and evaluates their resistance or robustness to a collection of potential threats. For the challenges considered, the response of the system to these challenges is assessed and expressed in terms of outcomes. The challenges to the system are given by the threats posed by potential proliferant States and sub-national adversaries on the nuclear systems. The characteristics of the Generation IV systems, both technical and institutional, are used to evaluate their response to the threats and determine their resistance against the proliferation threats and robustness against sabotage and theft threats. System response encompasses three main elements: (1) System Element Identification. The nuclear energy system is decomposed into smaller elements (subsystems) at a level amenable to further analysis. (2) Target Identification and Categorization. A systematic process is used to identify and select representative targets for different categories of pathways, within each system element, that actors (proliferant States or adversaries) might choose to use or …
Date: March 1, 2006
Creator: Bari, R.
System: The UNT Digital Library
Experimental investigation of the longitudinal beam dynamics in a photoinjector using a two-macroparticle bunch (open access)

Experimental investigation of the longitudinal beam dynamics in a photoinjector using a two-macroparticle bunch

We have developed a two-macroparticle bunch to explore the longitudinal beam dynamics through various components of the Fermilab/NICADD photoinjector. Such a two-macroparticle bunch is generated by splitting the ultraviolet pulse from the photocathode drive laser. The presented method allows the exploration of radiofrequency-induced compression in the 1.625 cell rf-gun and the booster cavity. It also allows a direct measurement of the momentum compaction of the magnetic bunch compressor. The measurements are compared with analytical and numerical models.
Date: March 1, 2006
Creator: Piot, P.; Tikhoplav, R.; Mihalcea, D. & Barov, N.
System: The UNT Digital Library
An Experimental Metagenome Data Management and AnalysisSystem (open access)

An Experimental Metagenome Data Management and AnalysisSystem

The application of shotgun sequencing to environmental samples has revealed a new universe of microbial community genomes (metagenomes) involving previously uncultured organisms. Metagenome analysis, which is expected to provide a comprehensive picture of the gene functions and metabolic capacity of microbial community, needs to be conducted in the context of a comprehensive data management and analysis system. We present in this paper IMG/M, an experimental metagenome data management and analysis system that is based on the Integrated Microbial Genomes (IMG) system. IMG/M provides tools and viewers for analyzing both metagenomes and isolate genomes individually or in a comparative context.
Date: March 1, 2006
Creator: Markowitz, Victor M.; Korzeniewski, Frank; Palaniappan, Krishna; Szeto, Ernest; Ivanova, Natalia N.; Kyrpides, Nikos C. et al.
System: The UNT Digital Library
An Experimentally Robust Technique for Halo Measurement (open access)

An Experimentally Robust Technique for Halo Measurement

We propose a model-independent quantity, L/G, to characterize non-Gaussian tails in beam profiles observed with the Fermilab Booster Ion Profile Monitor. This quantity can be considered a measure of beam halo in the Booster. We use beam dynamics and detector simulations to demonstrate that L/G is superior to kurtosis as an experimental measurement of beam halo when realistic beam shapes, detector effects and uncertainties are taken into account. We include the rationale and method of calculation for L/G in addition to results of the experimental studies in the Booster where we show that L/G is a useful halo discriminator.
Date: March 1, 2006
Creator: Amundson, J.; Pellico, W.; Spentzouris, P.; Sullivan, T. & Spentzouris, Linda
System: The UNT Digital Library
Extremely high energy cosmic neutrinos and relic neutrinos (open access)

Extremely high energy cosmic neutrinos and relic neutrinos

I review the essentials of ultrahigh-energy neutrino interactions, show how neutral-current detection and flavor tagging can enhance the scientific potential of neutrino telescopes, and sketch new studies on neutrino encounters with dark matter relics and on gravitational lensing of neutrinos.
Date: March 1, 2006
Creator: Quigg, Chris
System: The UNT Digital Library