Oscillation Detection Algorithm Development Summary Report and Test Plan (open access)

Oscillation Detection Algorithm Development Summary Report and Test Plan

Small signal stability problems are one of the major threats to grid stability and reliability in California and the western U.S. power grid. An unstable oscillatory mode can cause large-amplitude oscillations and may result in system breakup and large-scale blackouts. There have been several incidents of system-wide oscillations. Of them, the most notable is the August 10, 1996 western system breakup produced as a result of undamped system-wide oscillations. There is a great need for real-time monitoring of small-signal oscillations in the system. In power systems, a small-signal oscillation is the result of poor electromechanical damping. Considerable understanding and literature have been developed on the small-signal stability problem over the past 50+ years. These studies have been mainly based on a linearized system model and eigenvalue analysis of its characteristic matrix. However, its practical feasibility is greatly limited as power system models have been found inadequate in describing real-time operating conditions. Significant efforts have been devoted to monitoring system oscillatory behaviors from real-time measurements in the past 20 years. The deployment of phasor measurement units (PMU) provides high-precision time-synchronized data needed for estimating oscillation modes. Measurement-based modal analysis, also known as ModeMeter, uses real-time phasor measure-ments to estimate system oscillation …
Date: October 3, 2009
Creator: Zhou, Ning; Huang, Zhenyu; Tuffner, Francis K. & Jin, Shuangshuang
Object Type: Report
System: The UNT Digital Library
LIFE Chamber Chemical Equilibrium Simulations with Additive Hydrogen, Oxygen, and Nitrogen (open access)

LIFE Chamber Chemical Equilibrium Simulations with Additive Hydrogen, Oxygen, and Nitrogen

In order to enable continuous operation of a Laser Inertial confinement Fusion Energy (LIFE) engine, the material (fill-gas and debris) in the fusion chamber must be carefully managed. The chamber chemical equilibrium compositions for post-shot mixtures are evaluated to determine what compounds will be formed at temperatures 300-5000K. It is desired to know if carbon and or lead will deposit on the walls of the chamber, and if so: at what temperature, and what elements can be added to prevent this from happening. The simulation was conducted using the chemical equilibrium solver Cantera with a Matlab front-end. Solutions were obtained by running equilibrations at constant temperature and constant specific volume over the specified range of temperatures. It was found that if nothing is done, carbon will deposit on the walls once it cools to below 2138K, and lead below 838K. Three solutions to capture the carbon were found: adding pure oxygen, hydrogen/nitrogen combo, and adding pure nitrogen. The best of these was the addition of oxygen which would readily form CO at around 4000K. To determine the temperature at which carbon would deposit on the walls, temperature solutions to evaporation rate equations needed to be found. To determine how much …
Date: September 3, 2009
Creator: DeMuth, J A & Simon, A J
Object Type: Report
System: The UNT Digital Library
Large Time Projection Chambers for Rare Event Detection (open access)

Large Time Projection Chambers for Rare Event Detection

The Time Projection Chamber (TPC) concept [add ref to TPC section] has been applied to many projects outside of particle physics and the accelerator based experiments where it was initially developed. TPCs in non-accelerator particle physics experiments are principally focused on rare event detection (e.g. neutrino and darkmater experiments) and the physics of these experiments can place dramatically different constraints on the TPC design (only extensions to the traditional TPCs are discussed here). The drift gas, or liquid, is usually the target or matter under observation and due to very low signal rates a TPC with the largest active mass is desired. The large mass complicates particle tracking of short and sometimes very low energy particles. Other special design issues include, efficient light collection, background rejection, internal triggering and optimal energy resolution. Backgrounds from gamma-rays and neutrons are significant design issues in the construction of these TPCs. They are generally placed deep underground to shield from cosmogenic particles and surrounded with shielding to reduce radiation from the local surroundings. The construction materials have to be carefully screened for radiopurity as they are in close contact with the active mass and can be a signification source of background events. The TPC …
Date: November 3, 2009
Creator: Heffner, M
Object Type: Article
System: The UNT Digital Library
Integrated Genomic Analysis Identifies Clinically Relevant Subtypes of Glioblastoma Characterized by Abnormalities in PDGFRA, IDH1, EGFR, and NF1 (open access)

Integrated Genomic Analysis Identifies Clinically Relevant Subtypes of Glioblastoma Characterized by Abnormalities in PDGFRA, IDH1, EGFR, and NF1

The Cancer Genome Atlas Network recently cataloged recurrent genomic abnormalities in glioblastoma multiforme (GBM). We describe a robust gene expression-based molecular classification of GBM into Proneural, Neural, Classical, and Mesenchymal subtypes and integrate multidimensional genomic data to establish patterns of somatic mutations and DNA copy number. Aberrations and gene expression of EGFR, NF1, and PDGFRA/IDH1 each define the Classical, Mesenchymal, and Proneural subtypes, respectively. Gene signatures of normal brain cell types show a strong relationship between subtypes and different neural lineages. Additionally, response to aggressive therapy differs by subtype, with the greatest benefit in the Classical subtype and no benefit in the Proneural subtype. We provide a framework that unifies transcriptomic and genomic dimensions for GBM molecular stratification with important implications for future studies.
Date: September 3, 2009
Creator: Verhaak, Roel GW; Hoadley, Katherine A; Purdom, Elizabeth; Wang, Victoria; Qi, Yuan; Wilkerson, Matthew D et al.
Object Type: Article
System: The UNT Digital Library
Comparisons in Neutron Detection, as modeled by MCNPX, in Li-6 Glass, HE-3, BF-3, and Borated PVT (open access)

Comparisons in Neutron Detection, as modeled by MCNPX, in Li-6 Glass, HE-3, BF-3, and Borated PVT

With the potential shortage of He-3 being reported by venders, it is important to consider other materials for neutron detection. Traditional neutron detectors are composed of BF-3 and He-3. Recently Li-6 Glass and borated PVT have been presented as possible replacements. This work will compare the relative detection efficiencies and consider other factors to determine the most appropriate neutron detection material.
Date: April 3, 2009
Creator: Lawrence Lakeotes, Craig Marianno
Object Type: Article
System: The UNT Digital Library
Comparative analyses of gene copy number and mRNA expression in GBM tumors and GBM xenografts (open access)

Comparative analyses of gene copy number and mRNA expression in GBM tumors and GBM xenografts

Development of model systems that recapitulate the molecular heterogeneity observed among glioblastoma multiforme (GBM) tumors will expedite the testing of targeted molecular therapeutic strategies for GBM treatment. In this study, we profiled DNA copy number and mRNA expression in 21 independent GBM tumor lines maintained as subcutaneous xenografts (GBMX), and compared GBMX molecular signatures to those observed in GBM clinical specimens derived from the Cancer Genome Atlas (TCGA). The predominant copy number signature in both tumor groups was defined by chromosome-7 gain/chromosome-10 loss, a poor-prognosis genetic signature. We also observed, at frequencies similar to that detected in TCGA GBM tumors, genomic amplification and overexpression of known GBM oncogenes, such as EGFR, MDM2, CDK6, and MYCN, and novel genes, including NUP107, SLC35E3, MMP1, MMP13, and DDX1. The transcriptional signature of GBMX tumors, which was stable over multiple subcutaneous passages, was defined by overexpression of genes involved in M phase, DNA replication, and chromosome organization (MRC) and was highly similar to the poor-prognosis mitosis and cell-cycle module (MCM) in GBM. Assessment of gene expression in TCGA-derived GBMs revealed overexpression of MRC cancer genes AURKB, BIRC5, CCNB1, CCNB2, CDC2, CDK2, and FOXM1, which form a transcriptional network important for G2/M progression and/or checkpoint …
Date: April 3, 2009
Creator: Hodgson, J. Graeme; Yeh, Ru-Fang; Ray, Amrita; Wang, Nicholas J.; Smirnov, Ivan; Yu, Mamie et al.
Object Type: Article
System: The UNT Digital Library
Oligo and Poly-thiophene/Zno Hybrid Nanowire Solar Cells (open access)

Oligo and Poly-thiophene/Zno Hybrid Nanowire Solar Cells

We demonstrate the basic operation of an organic/inorganic hybrid single nanowire solar cell. End-functionalized oligo- and polythiophenes were grafted onto ZnO nanowires to produce p-n heterojunction nanowires. The hybrid nanostructures were characterized via absorption and electron microscopy to determine the optoelectronic properties and to probe the morphology at the organic/inorganic interface. Individual nanowire solar cell devices exhibited well-resolved characteristics with efficiencies as high as 0.036percent, Jsc = 0.32 mA/cm2, Voc = 0.4 V, and a FF = 0.28 under AM 1.5 illumination with 100 mW/cm2 light intensity. These individual test structures will enable detailed analysis to be carried out in areas that have been difficult to study in bulk heterojunction devices.
Date: November 3, 2009
Creator: Briseno, Alejandro L.; Holcombe, Thomas W.; Boukai, Akram I.; Garnett, Erik C.; Shelton, Steve W.; Frechet, Jean J. M. et al.
Object Type: Article
System: The UNT Digital Library
Towards a Scalable Fully-Implicit Fully-coupled Resistive MHD Formulation with Stabilized FE Methods (open access)

Towards a Scalable Fully-Implicit Fully-coupled Resistive MHD Formulation with Stabilized FE Methods

This paper presents an initial study that is intended to explore the development of a scalable fully-implicit stabilized unstructured finite element (FE) capability for low-Mach-number resistive MHD. The discussion considers the development of the stabilized FE formulation and the underlying fully-coupled preconditioned Newton-Krylov nonlinear iterative solver. To enable robust, scalable and efficient solution of the large-scale sparse linear systems generated by the Newton linearization, fully-coupled algebraic multilevel preconditioners are employed. Verification results demonstrate the expected order-of-acuracy for the stabilized FE discretization of a 2D vector potential form for the steady and transient solution of the resistive MHD system. In addition, this study puts forth a set of challenging prototype problems that include the solution of an MHD Faraday conduction pump, a hydromagnetic Rayleigh-Bernard linear stability calculation, and a magnetic island coalescence problem. Initial results that explore the scaling of the solution methods are presented on up to 4096 processors for problems with up to 64M unknowns on a CrayXT3/4. Additionally, a large-scale proof-of-capability calculation for 1 billion unknowns for the MHD Faraday pump problem on 24,000 cores is presented.
Date: June 3, 2009
Creator: Shadid, J N; Pawlowski, R P; Banks, J W; Chacon, L; Lin, P T & Tuminaro, R S
Object Type: Article
System: The UNT Digital Library
The Use of Haz-Flote to Efficiently Remove Mercury from Contaminated Materials (open access)

The Use of Haz-Flote to Efficiently Remove Mercury from Contaminated Materials

There are thousands of known contaminated sites in the United Stated, including Superfund sites (1500 to 2100 sites), RCRA corrective action sites (1500 to 3500 sites), underground storage tanks (295,000 sites), U.S. Department of Defense sites (7300 sites), U.S. Department of Energy sites (4,000 sites), mining refuse piles, and numerous other hazardous metals and organic contamination sites. Only a small percentage of these sites has been cleaned up. The development of innovative technologies to handle the various clean-up problems on a national and international scale is commonplace. Many innovative technologies have been developed that can be used to effectively remediate contaminated materials. Unfortunately, many of these technologies are only effective for materials coarser than approximately 200 mesh. In addition, these technologies usually require considerable investment in equipment, and the clean-up costs of soil material are relatively high - in excess of $100 to $500 per yd{sup 3}. These costs result from the elaborate nature of the processes, the costs for power, and the chemical cost. The fine materials are disposed of or treated at considerable costs. As a result, the costs often associated with amelioration of contaminated sites are high. Western Research institute is in the process of developing an …
Date: March 3, 2009
Creator: Brown, Terry
Object Type: Report
System: The UNT Digital Library
Physics of Neutralization of Intense Charged Particle Beam Pulses by a Background Plasma (open access)

Physics of Neutralization of Intense Charged Particle Beam Pulses by a Background Plasma

Neutralization and focusing of intense charged particle beam pulses by a background plasma forms the basis for a wide range of applications to high energy accelerators and colliders, heavy ion fusion, and astrophysics. For example, for ballistic propagation of intense ion beam pulses, background plasma can be used to effectively neutralize the beam charge and current, so that the self-electric and self-magnetic fields do not affect the ballistic propagation of the beam. From the practical perspective of designing advanced plasma sources for beam neutralization, a robust theory should be able to predict the self-electric and self-magnetic fields during beam propagation through the background plasma. The major scaling relations for the self-electric and self-magnetic fields of intense ion charge bunches propagating through background plasma have been determined taking into account the effects of transients during beam entry into the plasma, the excitation of collective plasma waves, the effects of gas ionization, finite electron temperature, and applied solenoidal and dipole magnetic fields. Accounting for plasma production by gas ionization yields a larger self-magnetic field of the ion beam compared to the case without ionization, and a wake of current density and self-magnetic field perturbations is generated behind the beam pulse. A solenoidal …
Date: September 3, 2009
Creator: Kaganovich, I. D.; Davidson, R. C.; Dorf, M. A.; Startsev, E. A.; Sefkow, A. B.; Friedman, A. F. et al.
Object Type: Article
System: The UNT Digital Library
Wave propagation in photonic crystals and metamaterials: Surface waves, nonlinearity and chirality (open access)

Wave propagation in photonic crystals and metamaterials: Surface waves, nonlinearity and chirality

Photonic crystals and metamaterials, both composed of artificial structures, are two interesting areas in electromagnetism and optics. New phenomena in photonic crystals and metamaterials are being discovered, including some not found in natural materials. This thesis presents my research work in the two areas. Photonic crystals are periodically arranged artificial structures, mostly made from dielectric materials, with period on the same order of the wavelength of the working electromagnetic wave. The wave propagation in photonic crystals is determined by the Bragg scattering of the periodic structure. Photonic band-gaps can be present for a properly designed photonic crystal. Electromagnetic waves with frequency within the range of the band-gap are suppressed from propagating in the photonic crystal. With surface defects, a photonic crystal could support surface modes that are localized on the surface of the crystal, with mode frequencies within the band-gap. With line defects, a photonic crystal could allow the propagation of electromagnetic waves along the channels. The study of surface modes and waveguiding properties of a 2D photonic crystal will be presented in Chapter 1. Metamaterials are generally composed of artificial structures with sizes one order smaller than the wavelength and can be approximated as effective media. Effective macroscopic parameters …
Date: December 3, 2009
Creator: Wang, Bingnan
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Development and Characterization of Boehmite Component Simulant (open access)

Development and Characterization of Boehmite Component Simulant

According to Bechtel National Inc.’s (BNI’s) Test Specification 24590-PTF-TSP-RT-06-006, Rev 0, “Simulant Development to Support the Development and Demonstration of Leaching and Ultrafiltration Pretreatment Processes,” simulants for boehmite, gibbsite, and filtration are to be developed that can be used in subsequent bench and integrated testing of the leaching/filtration processes. These simulants will then be used to demonstrate the leaching process and to help refine processing conditions that may impact safety basis considerations (Smith 2006). This report documents the results of the boehmite simulant development and blended simulant crossflow ultrafiltration leaching completed in accordance with the test plan TP-RPP-WTP-469 Rev 0 (WTP Doc. No. 24590- 101-TSA-W000-0004-182-00001 Rev 00A) prepared and approved in response to the cited test specification. This report also includes the results of the aluminate and anion effect on boehmite dissolution performed in accordance with the test plan TP-RPP-WTP-509, Rev 0 (WTP Doc. No. 24590-101-TSA-W000-0004-72-00019 Rev 00A) prepared and approved in response to the Test Specification 24590-WTP-TSP-RT-07-004, Rev 0 (Sundar 2007).
Date: June 3, 2009
Creator: Russell, Renee L.; Peterson, Reid A.; Smith, Harry D.; Rinehart, Donald E.; Aker, Pamela M. & Buck, Edgar C.
Object Type: Report
System: The UNT Digital Library
Alternative pre-mRNA splicing switches modulate gene expression in late erythropoiesis (open access)

Alternative pre-mRNA splicing switches modulate gene expression in late erythropoiesis

Differentiating erythroid cells execute a unique gene expression program that insures synthesis of the appropriate proteome at each stage of maturation. Standard expression microarrays provide important insight into erythroid gene expression but cannot detect qualitative changes in transcript structure, mediated by RNA processing, that alter structure and function of encoded proteins. We analyzed stage-specific changes in the late erythroid transcriptome via use of high-resolution microarrays that detect altered expression of individual exons. Ten differentiation-associated changes in erythroblast splicing patterns were identified, including the previously known activation of protein 4.1R exon 16 splicing. Six new alternative splicing switches involving enhanced inclusion of internal cassette exons were discovered, as well as 3 changes in use of alternative first exons. All of these erythroid stage-specific splicing events represent activated inclusion of authentic annotated exons, suggesting they represent an active regulatory process rather than a general loss of splicing fidelity. The observation that 3 of the regulated transcripts encode RNA binding proteins (SNRP70, HNRPLL, MBNL2) may indicate significant changes in the RNA processing machinery of late erythroblasts. Together, these results support the existence of a regulated alternative pre-mRNA splicing program that is critical for late erythroid differentiation.
Date: February 3, 2009
Creator: Yamamoto, Miki L.; Clark, Tyson A.; Gee, Sherry L.; Kang, Jeong-Ah; Schweitzer, Anthony C.; Wickrema, Amittha et al.
Object Type: Article
System: The UNT Digital Library
Elements of Successful and Safe Fusion Experiment Operations (open access)

Elements of Successful and Safe Fusion Experiment Operations

A group of fusion safety professionals contribute to a Joint Working Group (JWG) that performs occupational safety walkthroughs of US and Japanese fusion experiments on a routine basis to enhance the safety of visiting researchers. The most recent walkthrough was completed in Japan in March 2008 by the US Safety Monitor team. This paper gives the general conclusions on fusion facility personnel safety that can be drawn from the series of walkthroughs.
Date: February 3, 2009
Creator: Rule, K.; Cadwallader, L.; Takase, Y.; Norimatsu, T.; Kaneko, O.; Sato, M. et al.
Object Type: Article
System: The UNT Digital Library
A Fusing Switch for Fault Suppression in the SNS High Voltage Converter Modulators (open access)

A Fusing Switch for Fault Suppression in the SNS High Voltage Converter Modulators

The High Voltage Converter Modulators (HVCMs) at the Spallation Neutron Source (SNS) have operated in excess of a combined 250,000 hours. Performance and reliability improvements to the HVCM are ongoing to increase modulator availability as accelerator system demands increase. There is a relatively large amount of energy storage in the HVCMs, {approx}180 kJ. This energy has the potential to dump into unsuppressed faults, cause damage, and increase the time to repair. The 'fusing switch' concept involves isolation of this stored energy from the location of the most common faults. This paper introduces this concept and its application to the HVCMs.
Date: August 3, 2009
Creator: Kemp, Mark A.; Burkhart, Craig; Nguyen, Minh N. & Anderson, David E.
Object Type: Article
System: The UNT Digital Library
Treatability Test Report on Mending the in Situ Redox Manipulation Barrier Using Nano-Size Zero Valent Iron (open access)

Treatability Test Report on Mending the in Situ Redox Manipulation Barrier Using Nano-Size Zero Valent Iron

None
Date: November 3, 2009
Creator: Petersen, S. W.
Object Type: Report
System: The UNT Digital Library
SAVANNAH RIVER SITE R REACTOR DISASSEMBLY BASIN IN SITU DECOMMISSIONING (open access)

SAVANNAH RIVER SITE R REACTOR DISASSEMBLY BASIN IN SITU DECOMMISSIONING

The US DOE concept for facility in-situ decommissioning (ISD) is to physically stabilize and isolate in tact, structurally sound facilities that are no longer needed for their original purpose of, i.e., generating (reactor facilities), processing(isotope separation facilities) or storing radioactive materials. The 105-R Disassembly Basin is the first SRS reactor facility to undergo the in-situ decommissioning (ISD) process. This ISD process complies with the105-R Disassembly Basin project strategy as outlined in the Engineering Evaluation/Cost Analysis for the Grouting of the R-Reactor Disassembly Basin at the Savannah River Site and includes: (1) Managing residual water by solidification in-place or evaporation at another facility; (2) Filling the below grade portion of the basin with cementitious materials to physically stabilize the basin and prevent collapse of the final cap - Sludge and debris in the bottom few feet of the basin will be encapsulated between the basin floor and overlying fill material to isolate if from the environment; (3) Demolishing the above grade portion of the structure and relocating the resulting debris to another location or disposing of the debris in-place; and (4) Capping the basin area with a concrete slab which is part of an engineered cap to prevent inadvertent intrusion. The …
Date: December 3, 2009
Creator: Langton, C.; Blankenship, J.; Griffin, W. & Serrato, M.
Object Type: Article
System: The UNT Digital Library
Numerical Tests and Properties of Waves in Radiating Fluids (open access)

Numerical Tests and Properties of Waves in Radiating Fluids

We discuss the properties of an analytical solution for waves in radiating fluids, with a view towards its implementation as a quantitative test of radiation hydrodynamics codes. A homogeneous radiating fluid in local thermodynamic equilibrium is periodically driven at the boundary of a one-dimensional domain, and the solution describes the propagation of the waves thus excited. Two modes are excited for a given driving frequency, generally referred to as a radiative acoustic wave and a radiative diffusion wave. While the analytical solution is well known, several features are highlighted here that require care during its numerical implementation. We compare the solution in a wide range of parameter space to a numerical integration with a Lagrangian radiation hydrodynamics code. Our most significant observation is that flux-limited diffusion does not preserve causality for waves on a homogeneous background.
Date: September 3, 2009
Creator: Johnson, B M & Klein, R I
Object Type: Article
System: The UNT Digital Library
Prospects for Integrating a Hollow Electron Lens into the LHC Collimation System (open access)

Prospects for Integrating a Hollow Electron Lens into the LHC Collimation System

None
Date: August 3, 2009
Creator: Smith, Jeffrey Claiborne; Assmann, Ralph; Previtali, Valentina; Shiltsev, Vladimir & Valishev, Alexander
Object Type: Article
System: The UNT Digital Library
A Domino Theory of Flavor (open access)

A Domino Theory of Flavor

We argue that the fermion masses and mixings are organized in a specific pattern. The approximately equal hierarchies between successive generations, the sizes of the mixing angles, the heaviness of just the top quark, and the approximate down-lepton equality can all be accommodated by many flavor models but can appear ad hoc. We present a simple, predictive mechanism to explain these patterns. All generations are treated democratically and the flavor symmetries are broken collectively by only two allowed couplings in flavor-space, a vector and matrix, with arbitrary {Omicron}(1) entries. Repeated use of these flavor symmetry breaking spurions radiatively generates the Yukawa couplings with a natural hierarchy. We demonstrate this idea with two models in a split supersymmetric grand unified framework, with minimal additional particle content at the unification scale. Although flavor is generated at the GUT scale, there are several potentially testable predictions. In our minimal model the usual prediction of exact b-{tau} unification is replaced by the SU(5) breaking relation m{sub {tau}}/m{sub b} = 3/2, in better agreement with observations. Other SU(5) breaking effects in the fermion masses can easily arise directly from the flavor model itself. The symmetry breaking that triggers the generation of flavor necessarily gives rise …
Date: August 3, 2009
Creator: Graham, Peter W. & Rajendran, Surjeet
Object Type: Article
System: The UNT Digital Library
Homology with vesicle fusion mediator syntaxin-1a predicts determinants ofepimorphin/syntaxin-2 function in mammary epithelial morphogenesis (open access)

Homology with vesicle fusion mediator syntaxin-1a predicts determinants ofepimorphin/syntaxin-2 function in mammary epithelial morphogenesis

We have shown that branching morphogenesis of mammary ductal structures requires the action of the morphogen epimorphin/syntaxin-2. Epimorphin, originally identified as an extracellular molecule, is identical to syntaxin-2, an intracellular molecule that is a member of the extensively investigated syntaxin family of proteins that mediate vesicle trafficking. We show here that although epimorphin/syntaxin-2 is highly homologous to syntaxin-1a, only epimorphin/syntaxin-2 can stimulate mammary branching morphogenesis. We construct a homology model of epimorphin/syntaxin-2 based on the published structure of syntaxin-1a, and we use this model to identify the structural motif responsible for the morphogenic activity. We identify four residues located within the cleft between helices B and C that differ between syntaxin-1a and epimorphin/syntaxin-2; through site-directed mutagenesis of these four amino acids, we confer the properties of epimorphin for cell adhesion, gene activation, and branching morphogenesis onto the inactive syntaxin-1a template. These results provide a dramatic demonstration of the use of structural information about one molecule to define a functional motif of a second molecule that is related at the sequence level but highly divergent functionally.
Date: June 3, 2009
Creator: Chen, Connie S.; Nelson, Celeste M.; Khauv, Davitte; Bennett, Simone; Radisky, Evette S.; Hirai, Yohei et al.
Object Type: Article
System: The UNT Digital Library
Feasibility Analysis For Heating Tribal Buildings with Biomass (open access)

Feasibility Analysis For Heating Tribal Buildings with Biomass

This report provides a feasibility study for the heating of Tribal buildings using woody biomass. The study was conducted for the Confederated Salish and Kootenai Tribes of the Flathead Reservation in western Montana. S&K Holding Company and TP Roche Company completed the study and worked together to provide the final report. This project was funded by the DOE's Tribal Energy Program.
Date: March 3, 2009
Creator: Clairmont, Steve; Bourdon, Micky; Roche, Tom & Frye, Colene
Object Type: Report
System: The UNT Digital Library
Conceptual Design of the Drive Beam for a PWFA-LC (open access)

Conceptual Design of the Drive Beam for a PWFA-LC

Plasma Wake-Field Acceleration (PWFA) has demonstrated acceleration gradients above 50 GeV/m. Simulations have shown drive/witness bunch configurations that yield small energy spreads in the accelerated witness bunch and high energy transfer efficiency from the drive bunch to the witness bunch, ranging from 30% for a Gaussian drive bunch to 95% for bunch with triangular shaped longitudinal profile. These results open the opportunity for a linear collider that could be compact, efficient and more cost effective than the present microwave technologies. A concept of a PWFA-based Linear Collider (PWFA-LC) has been developed by the PWFA collaboration. Here we will describe the conceptual design and optimization of the drive beam, which includes the drive beam linac and distribution system. We apply experience of the CLIC drive beam design and demonstration in the CLIC Test Facility (CTF3) to this study. We discuss parameter optimization of the drive beam linac structure and evaluate the drive linac efficiency in terms of the drive beam distribution scheme and the klystron/modulator requirements.
Date: August 3, 2009
Creator: Pei, S.; Hogan, M. J.; Raubenheimer, T. O.; Seryi, A.; Braun, H. H.; Corsini, R. et al.
Object Type: Article
System: The UNT Digital Library
A Bottom-Up Approach to SUSY Analyses (open access)

A Bottom-Up Approach to SUSY Analyses

This paper proposes a new way to perform event generation and analysis in searches for new physics at the LHC. An abstract notation is used to describe the new particles on a level which better corresponds to detector resolution of LHC experiments. In this way the SUSY discovery space can be decomposed into a small number of eigenmodes each with only a few parameters, which allows to investigate the SUSY parameter space in a model-independent way. By focusing on the experimental observables for each process investigated the Bottom-Up Approach allows to systematically study the boarders of the experimental efficiencies and thus to extend the sensitivity for new physics.
Date: August 3, 2009
Creator: Horn, Claus
Object Type: Article
System: The UNT Digital Library