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1 GeV CW nonscaling FFAG for ADS, and magnet parameters (open access)

1 GeV CW nonscaling FFAG for ADS, and magnet parameters

Multi-MW proton driver capability remains a challenging, critical technology for many core HEP programs, particularly the neutrino ones such as the Muon Collider and Neutrino factory, and for high-profile energy applications such as Accelerator Driven Subcritical Reactors (ADS) and Accelerator Transmutation of Waste for nuclear power and waste management. Work is focused almost exclusively on an SRF linac, as, to date, no re-circulating accelerator can attain the 10-20 MW capability necessary for the nuclear applications. Recently, the concept of isochronous orbits has been explored and developed for nonscaling FFAGs using powerful new methodologies in FFAG accelerator design. Work is progressing on a stable, high-intensity, 1 GeV isochronous FFAG. Initial specifications of novel magnets with the nonlinear radial fields required to support isochronous operation are also reported here.
Date: May 20, 2012
Creator: Johnstone, C.; Meot, F.; Snopok, P. & Weng, W.
Object Type: Article
System: The UNT Digital Library
The 3.8% Medicare Contribution Tax on Unearned Income, Including Real Estate Transactions (open access)

The 3.8% Medicare Contribution Tax on Unearned Income, Including Real Estate Transactions

This reports summarizes a 3.8% Medicare contribution tax on unearned income and provides examples of how it is applied.
Date: May 18, 2012
Creator: Keightley, Mark P.
Object Type: Report
System: The UNT Digital Library
A 3 TeV Muon Collider Lattice Design (open access)

A 3 TeV Muon Collider Lattice Design

A new lattice for 3 TeV c.o.m. energy with {beta}* = 5mm was developed which follows the basic concept of the earlier 1.5 TeV design but uses quad triplets for the final focus in order to keep the maximum magnet strength and aperture close to those in 1.5 TeV case. Another difference is employment of combined-function magnets with the goal to lower heat deposition in magnet cold mass and to eliminate bending field free regions which produce 'hot spots' of neutrino radiation that can be an issue at higher energy. The proposed lattice is shown to satisfy the requirements on luminosity, dynamic aperture and momentum acceptance.
Date: May 1, 2012
Creator: Alexahin, Y. & Gianfelice-Wendt, E.
Object Type: Article
System: The UNT Digital Library
6 Batch Injection and Slipped Beam Tune Measurements in Fermilab?s Main Injector (open access)

6 Batch Injection and Slipped Beam Tune Measurements in Fermilab?s Main Injector

During NOVA operations it is planned to run the Fermilab Recycler in a 12 batch slip stacking mode. In preparation for this, measurements of the tune during a six batch injection and then as the beam is decelerated by changing the RF frequency have been carried out in the Main Injector. The coherent tune shifts due to the changing beam intensity were measured and compared well with the theoretically expected tune shift. The tune shifts due to changing RF frequency, required for slip stacking, also compare well with the linear theory, although some nonlinear affects are apparent at large frequency changes. These results give us confidence that the expected tunes shifts during 12 batch slip stacking Recycler operations can be accommodated.
Date: May 1, 2012
Creator: Scott, D. J.; Capista, D.; Kourbanis, I.; Seiya, K. & Yan, M.-J.
Object Type: Article
System: The UNT Digital Library
9-Lipoxygenase Oxylipin Pathway in Plant Response to Biotic Stress (open access)

9-Lipoxygenase Oxylipin Pathway in Plant Response to Biotic Stress

The activity of plant 9-lipoxygenases (LOXs) influences the outcome of Arabidopsis thaliana interaction with pathogen and insects. Evidence provided here indicates that in Arabidopsis, 9-LOXs facilitate infestation by Myzus persicae, commonly known as the green peach aphid (GPA), a sap-sucking insect, and infection by the fungal pathogen Fusarium graminearum. in comparison to the wild-type plant, lox5 mutants, which are deficient in a 9-lipoxygenase, GPA population was smaller and the insect spent less time feeding from sieve elements and xylem, thus resulting in reduced water content and fecundity of GPA. LOX5 expression is induced rapidly in roots of GPA-infested plants. This increase in LOX5 expression is paralleled by an increase in LOX5-synthesized oxylipins in the root and petiole exudates of GPA-infested plants. Micrografting experiments demonstrated that GPA population size was smaller on plants in which the roots were of the lox5 mutant genotype. Exogenous treatment of lox5 mutant roots with 9-hydroxyoctadecanoic acid restored water content and population size of GPA on lox5 mutants. Together, these results suggest that LOX5 genotype in roots is critical for facilitating insect infestation of Arabidopsis. in Arabidopsis, 9-LOX function is also required for facilitating infection by F. graminearum, which is a leading cause of Fusarium head …
Date: May 2012
Creator: Nalam, Vamsi J.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
10 CFR 830 Major Modification Determination for Advanced Test Reactor LEU Fuel Conversion (open access)

10 CFR 830 Major Modification Determination for Advanced Test Reactor LEU Fuel Conversion

The Advanced Test Reactor (ATR), located in the ATR Complex of the Idaho National Laboratory (INL), was constructed in the 1960s for the purpose of irradiating reactor fuels and materials. Other irradiation services, such as radioisotope production, are also performed at ATR. The ATR is fueled with high-enriched uranium (HEU) matrix (UAlx) in an aluminum sandwich plate cladding. The National Nuclear Security Administration Global Threat Reduction Initiative (GTRI) strategic mission includes efforts to reduce and protect vulnerable nuclear and radiological material at civilian sites around the world. Converting research reactors from using HEU to low-enriched uranium (LEU) was originally started in 1978 as the Reduced Enrichment for Research and Test Reactors (RERTR) Program under the U.S. Department of Energy (DOE) Office of Science. Within this strategic mission, GTRI has three goals that provide a comprehensive approach to achieving this mission: The first goal, the driver for the modification that is the subject of this determination, is to convert research reactors from using HEU to LEU. Thus the mission of the ATR LEU Fuel Conversion Project is to convert the ATR and Advanced Test Reactor Critical facility (ATRC) (two of the six U.S. High-Performance Research Reactors [HPRR]) to LEU fuel by …
Date: May 1, 2012
Creator: Christensen, Boyd D.; Lehto, Michael A. & Duckwitz, Noel R.
Object Type: Report
System: The UNT Digital Library
10 CFR 830 Major Modification Determination for Advanced Test Reactor RDAS and LPCIS Replacement (open access)

10 CFR 830 Major Modification Determination for Advanced Test Reactor RDAS and LPCIS Replacement

The replacement of the ATR Control Complex's obsolete computer based Reactor Data Acquisition System (RDAS) and its safety-related Lobe Power Calculation and Indication System (LPCIS) software application is vitally important to ensure the ATR remains available to support this national mission. The RDAS supports safe operation of the reactor by providing 'real-time' plant status information (indications and alarms) for use by the reactor operators via the Console Display System (CDS). The RDAS is a computer support system that acquires analog and digital information from various reactor and reactor support systems. The RDAS information is used to display quadrant and lobe powers via a display interface more user friendly than that provided by the recorders and the Control Room upright panels. RDAS provides input to the Nuclear Engineering ATR Surveillance Data System (ASUDAS) for fuel burn-up analysis and the production of cycle data for experiment sponsors and the generation of the Core Safety Assurance Package (CSAP). RDAS also archives and provides for retrieval of historical plant data which may be used for event reconstruction, data analysis, training and safety analysis. The RDAS, LPCIS and ASUDAS need to be replaced with state-of-the-art technology in order to eliminate problems of aged computer systems, …
Date: May 1, 2012
Creator: Korns, David E.
Object Type: Report
System: The UNT Digital Library
120-Channel, Chronically Implantable, Wireless, Polymer Neural Interface (open access)

120-Channel, Chronically Implantable, Wireless, Polymer Neural Interface

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Date: May 9, 2012
Creator: Tooker, A; Shah, K; Tolosa, V; Sheth, H; Felix, S; Delima, T et al.
Object Type: Article
System: The UNT Digital Library
2012 Aspen Winter Conferences on High Energy and Astrophysics (open access)

2012 Aspen Winter Conferences on High Energy and Astrophysics

Aspen Center for Physics Project Summary DE-SC0007313 Budget Period: 1/1/2012 to 12/31/2012 The Hunt for New Particles, from the Alps to the Plains to the Rockies The 2012 Aspen Winter Conference on Particle Physics was held at the Aspen Center for Physics from February 11 to February 17, 2012. Sixty-seven participants from nine countries, and several universities and national labs attended the workshop titled, The Hunt for New Particles, from the Alps to the Plains to the Rockies. There were 53 formal talks, and a considerable number of informal discussions held during the week. The weeks events included a public lecture-Hunting the Dark Universe given by Neal Weiner from New York University) and attended by 237 members of the public, and a physics cafe geared for high schoolers that is a discussion with physicists conducted by Spencer Chang (University of Oregon), Matthew Reece (Harvard University) and Julia Shelton (Yale University) and attended by 67 locals and visitors. While there were no published proceedings, some of the talks are posted online and can be Googled. The workshop was organized by John Campbell (Fermilab), Patrick Fox (Fermilab), Ivan Furic (University of Florida), Eva Halkiadakis (Rutgers University) and Daniel Whiteson (University of California …
Date: May 1, 2012
Creator: Campbell, John; Olivier, Dore; Fox, Patrick; Furic, Ivan; Halkiadakis, Eva; Schmidt, Fabian et al.
Object Type: Report
System: The UNT Digital Library
2020 Census: Additional Steps Are Needed to Build on Early Planning (open access)

2020 Census: Additional Steps Are Needed to Build on Early Planning

A letter report issued by the Government Accountability Office with an abstract that begins "The Census Bureau’s (Bureau) early planning and preparation efforts for the 2020 Census are consistent with most leading practices in each of the three management areas GAO reviewed. For example, with respect to its effort to transform its decennial organization, top Bureau leadership has been driving the transformation, and the agency has focused on a key set of principles as it begins to roll-out the strategy to staff. Furthermore, the Bureau has created a timeline to build momentum and show progress. At the same time, however, the amount of change-related activity the Bureau is considering as part of its reorganization of its decennial directorate may not be aligned with the resources the Bureau has allocated to plan, coordinate, and carry it out, and, as a result, the planned transformation efforts may not be sustainable or successful."
Date: May 17, 2012
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
3D simulations of multipacting in the 56 MHz SRF cavity (open access)

3D simulations of multipacting in the 56 MHz SRF cavity

The 56 MHz SRF Quarter-Wave Resonator (QWR) is designed for RHIC as a storage cavity to improve the collider performance. 2D multipacting simulation has been done for the cavity alone. Ripples were added to the outer body of the cavity for multipacting suppression based on the simulation findings. During operation, there will be four higher order mode (HOM) couplers. All of these components will be exposed to high RF fields. In this paper we compare 2D and 3D codes simulation results for multipacting in the cavity. We also report 3D simulation results for multipacting simulation at the couplers.
Date: May 20, 2012
Creator: Q., Wu; Belomestnykh, S.; Ge, L.; Ko, K.; Li, Z.; Ng, C. et al.
Object Type: Article
System: The UNT Digital Library
9978 AND 9975 TYPE B PACKAGING INTERNAL DATA COLLECTION FEASIBILITY TESTING (open access)

9978 AND 9975 TYPE B PACKAGING INTERNAL DATA COLLECTION FEASIBILITY TESTING

The objective of this report is to document the findings from a series of proof-of-concept tests performed by Savannah River National Laboratory (SRNL) R and D Engineering, for the DOE Packaging Certification Program to determine if a viable radio link could be established from within the stainless steel confines of several drum-style DOE certified Type B radioactive materials packagings. Two in-hand, off-the-shelf radio systems were tested. The first system was a Wi-Fi Librestream Onsight{trademark} camera with a Fortress ES820 Access Point and the second was the On-Ramp Wireless Ultra-Link Processing{trademark} (ULP) radio system. These radio systems were tested within the Model 9975 and 9978 Type B packagings at the SRNL. This report documents the test methods and results. A path forward will also be recommended.
Date: May 7, 2012
Creator: Fogle, R.
Object Type: Report
System: The UNT Digital Library
Absence of Debye Sheaths Due to Secondary Electron Emission (open access)

Absence of Debye Sheaths Due to Secondary Electron Emission

A bounded plasma where the hot electrons impacting the walls produce more than one secondary on average is studied via particle-in-cell simulation. It is found that no classical Debye sheath or space-charge limited sheath exists. Ions are not drawn to the walls and electrons are not repelled. Hence the unconfined plasma electrons travel unobstructed to the walls, causing extreme particle and energy fluxes. Each wall has a positive charge, forming a small potential barrier or "inverse sheath" that pulls some secondaries back to the wall to maintain the zero current condition.
Date: May 11, 2012
Creator: Campanell, M. D.; Khabrov, A. & Kaganovich, I. D.
Object Type: Report
System: The UNT Digital Library
Absolute Determination of Charge-Coupled Device Quantum Detection Efficiency Using Si K-Edge X-Ray Absorption Fine Structure (open access)

Absolute Determination of Charge-Coupled Device Quantum Detection Efficiency Using Si K-Edge X-Ray Absorption Fine Structure

We report a method to determine the quantum detection efficiency and the absorbing layers on a front-illuminated charge-coupled device (CCD). The CCD under study, as part of a crystal spectrometer, measures intense continuum x-ray emission from a picosecond laser-produced plasma and spectrally resolves the Si K-edge x-ray absorption fine structure features due to the electrode gate structure of the device. The CCD response across the Si K-edge shows a large discontinuity as well as a number of oscillations that are identified individually and uniquely from Si, SiO{sub 2}, and Si{sub 3}N{sub 4} layers. From the spectral analysis of the structure and K-edge discontinuity, the active layer thickness and the different absorbing layers thickness can be determined precisely. A precise CCD detection model from 0.2-10 keV can be deduced from this highly sensitive technique.
Date: May 6, 2012
Creator: Dunn, J. & Steel, A. B.
Object Type: Article
System: The UNT Digital Library
Absorptive Capacity:  An Empirical Examination of the Phenomenon and Relationships with Firm Capabilities (open access)

Absorptive Capacity: An Empirical Examination of the Phenomenon and Relationships with Firm Capabilities

The field of strategic management addresses challenges that firms encounter in an attempt to remain competitive. The ability to explain variation in firm success through examination of knowledge flows has become a prominent focus of research in the strategic management literature. Specifically, researchers have sought to further examine how firms convert knowledge, a phenomenon conceptualized as absorptive capacity. Absorptive capacity is the firm’s ability to acquire, assimilate, transform, and exploit knowledge. Few studies have captured the richness and multi-dimensionality of absorptive capacity, and it remains to be understood how the dimensions of the phenomenon convert knowledge. Furthermore, how absorptive capacity influences the firm remains to be understood. To address these research gaps, this dissertation seeks to (1) determine how absorptive capacity converts knowledge, and (2) determine how absorptive capacity influences firm capabilities. The research questions are investigated using structural modeling techniques to analyze data collected from software-industry firms. The findings offer contributions to the absorptive capacity and capability literatures. For example, absorptive capacity is hypothesized to consist of complex relationships among its internal dimensions. However, findings of this study suggest the relationships among the dimensions are linear in nature. This finding is in line with the theoretical foundations of and …
Date: May 2012
Creator: Daspit, Josh
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Accelerators for Intensity Frontier Research (open access)

Accelerators for Intensity Frontier Research

In 2008, the Particle Physics Project Prioritization Panel identified three frontiers for research in high energy physics, the Energy Frontier, the Intensity Frontier, and the Cosmic Frontier. In this paper, I will describe how Fermilab is configuring and upgrading the accelerator complex, prior to the development of Project X, in support of the Intensity Frontier.
Date: May 11, 2012
Creator: Derwent, Paul
Object Type: Article
System: The UNT Digital Library
Adding a MOAB Geometry Interface to SHARP Structural Mechanics (open access)

Adding a MOAB Geometry Interface to SHARP Structural Mechanics

The authors briefly summarize the development of, and test experience with, an initial data interface between the structural mechanics code Diablo and the SHARP reactor simulation system data hub MOAB. That interface has been exercised both to write MOAB databases from Diablo, and then also to use such a database to read in part of a simulation definition for a subsequent Diablo execution. All enhancements are integrated into the central Diablo source repository. The SHARP software system for advanced simulation of nuclear reactors and power plant systems is sponsored by DOE's Nuclear Energy Advanced Modeling and Simulation (NEAMS) program. SHARP has been architected as a federation of single-physics simulation tools to permit flexibility in programming langugages and leveraging of past and on-going investments. Solution of multi-physics problems will be coordinated by, and data passed through, a central 'hub'. SHARP's hub implementation is utilizing MOAB: a Mesh-Oriented datABase. This same data hub approach is also intended to enable multi-resolution simulations, e.g, lower-dimension plant-scale simulations can be informed by high-fidelity 3D models of particular critical components.
Date: May 28, 2012
Creator: Ferencz, R M & Hodge, N E
Object Type: Report
System: The UNT Digital Library
Addressing Medicare Hospital Readmissions (open access)

Addressing Medicare Hospital Readmissions

This report highlights the issue of one-fifth of medicare patients in 2005 being readmitted to a hospital within thirty days time. These readmissions put a strain on the budget, the majority of which it is estimated may be avoidable. The report notes that Medicare as a program is working on moving around those difficulties, without reducing the quality of care.
Date: May 25, 2012
Creator: Tilson, Sibyl
Object Type: Report
System: The UNT Digital Library
Adoptive Parenthood: an Exploratory Study of the Influence of Pre-adoption Communication Satisfaction on Post-adoption Family Adjustment and Coping (open access)

Adoptive Parenthood: an Exploratory Study of the Influence of Pre-adoption Communication Satisfaction on Post-adoption Family Adjustment and Coping

There are over a million adopted children in the United States, which makes up over 2% of the population. in spite of the fact that the majority of children are adopted into loving and caring homes, early life trauma puts them at higher risk for developing behavioral and emotional problems than non-adopted children. Due to these issues, many adoptive parents encounter post-adoption stress. This stress is often linked to minimal education regarding short- and long-term challenges associated with adoption. the adoption agency is likely the best group for addressing challenges, yet few researchers have studied adoption agency communication and adoptive parent adjustment. in this study I examined pre-adoption communication satisfaction, post-adoption adjustment (life change and parental adjustment), and coping strategies. Hypothesis 1 questioned the relationship between adoptive parents’ pre-adoption communication satisfaction with their social workers and post-adoption family adjustment; this hypothesis was supported only for problems related to home and work life adjustment. Hypothesis 2 predicted coping strategies would mediate the relationship between communication satisfaction and family adjustment. H2 was not supported for both life change and parental adjustment. Research Questions 1a and 1b inquired about the coping strategy that had an impact on life change and parental adjustment; escape-avoidance …
Date: May 2012
Creator: Seebeck, Lara N.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Advanced Electric Submersible Pump Design Tool for Geothermal Applications (open access)

Advanced Electric Submersible Pump Design Tool for Geothermal Applications

Electrical Submersible Pumps (ESPs) present higher efficiency, larger production rate, and can be operated in deeper wells than the other geothermal artificial lifting systems. Enhanced Geothermal Systems (EGS) applications recommend lifting 300 C geothermal water at 80kg/s flow rate in a maximum 10-5/8-inch diameter wellbore to improve the cost-effectiveness. In this paper, an advanced ESP design tool comprising a 1D theoretical model and a 3D CFD analysis has been developed to design ESPs for geothermal applications. Design of Experiments was also performed to optimize the geometry and performance. The designed mixed-flow type centrifugal impeller and diffuser exhibit high efficiency and head rise under simulated EGS conditions. The design tool has been validated by comparing the prediction to experimental data of an existing ESP product.
Date: May 31, 2012
Creator: Qi, Xuele; Turnquist, Norman & Ghasripoor, Farshad
Object Type: Article
System: The UNT Digital Library
Advanced Flow Battery Electrodes (open access)

Advanced Flow Battery Electrodes

Advanced Research Projects Agency-Energy project sheet summarizing general information about the Grid-Scale Rampable Intermittent Dispatchable Storage (GRIDS) program including critical needs, innovation and advantages, impacts, and contact information. This sheet discusses advanced flow battery electrodes as part of the "Low-Cost, High-Performance 50-Year Electrode" project.
Date: May 21, 2012
Creator: Primus Power
Object Type: Text
System: The UNT Digital Library
Advanced Flywheel Composite Rotors (open access)

Advanced Flywheel Composite Rotors

Advanced Research Projects Agency-Energy project sheet summarizing general information about the Grid-Scale Rampable Intermittent Dispatchable Storage (GRIDS) program including critical needs, innovation and advantages, impacts, and contact information. This sheet discusses advanced flywheel composite rotors as part of the "Low-Cost, High-Energy Density Flywheel Storage Grid Demonstration" project.
Date: May 18, 2012
Creator: Boeing Aerospace Company
Object Type: Text
System: The UNT Digital Library
Advanced High-Speed 16-Bit Digitizer System (open access)

Advanced High-Speed 16-Bit Digitizer System

The fastest commercially available 16-bit ADC can only perform around 200 mega-samples per second (200 MS/s). Connecting ADC chips together in eight different time domains increases the quantity of samples taken by a factor of eight. This method of interleaving requires that the input signal being sampled is split into eight identical signals and arrives at each ADC chip at the same point in time. The splitting of the input signal is performed in the analog front end containing a wideband filter that impedance matches the input signal to the ADC chips. Each ADC uses a clock to tell it when to perform a conversion. Using eight unique clocks spaced in 45-degree increments is the method used to time shift when each ADC chip performs its conversion. Given that this control clock is a fixed frequency, the clock phase shifting is accomplished by tightly controlling the distance that the clock must travel, resulting in a time delay. The interleaved ADC chips will now generate digital data in eight different time domains. These data are processed inside a field-programmable gate array (FPGA) to move the data back into a single time domain and store it into memory. The FPGA also contains …
Date: May 1, 2012
Creator: unknown
Object Type: Article
System: The UNT Digital Library
Advanced Metal-Hydrides-Based Thermal Battery (open access)

Advanced Metal-Hydrides-Based Thermal Battery

Advanced Research Projects Agency-Energy project sheet summarizing general information about the High Energy Advanced Thermal Storage (HEATS) program including critical needs, innovation and advantages, impacts, and contact information. This sheet discusses an advanced metal-hydrides-based thermal battery as part of the "A New Generation of High Density Thermal Battery Based on Advanced Metal Hydrides" project.
Date: May 25, 2012
Creator: University of Utah
Object Type: Text
System: The UNT Digital Library