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Alternatives to the Maroni Process for Tritium Recovery in Fusion Reactors: Avoiding Volatile Hydrogen Fluoride and High-Temperature High-Speed Rotating Machinery (open access)

Alternatives to the Maroni Process for Tritium Recovery in Fusion Reactors: Avoiding Volatile Hydrogen Fluoride and High-Temperature High-Speed Rotating Machinery

None
Date: October 15, 2013
Creator: Farmer, J.; El-Dasher, B.; Bandhauer, T.; Rubenchik, A.; Reyes, S.; Dunne, M. et al.
Object Type: Report
System: The UNT Digital Library
Architecture-Aware Algorithms for Scalable Performance and Resilience on Heterogeneous Architectures (open access)

Architecture-Aware Algorithms for Scalable Performance and Resilience on Heterogeneous Architectures

The goal of the Extreme-scale Algorithms & Software Institute (EASI) is to close the �application-architecture performance gap� by exploring algorithms and runtime improvements that will enable key science applications to better exploit the architectural features of DOE extreme-scale systems. For the past year of the project, our efforts at the University of Tennessee have concentrated on, and made significant progress related to, the following high-level EASI goals: � Develop multi-precision and architecture-aware implementations of Krylov, Poisson, Helmholtz solvers, and dense factorizations for heterogeneous multi-core systems; � Explore new methods of algorithm resilience, and develop new algorithms with these capabilities; � Develop runtime support for adaptable algorithms that are dealing with resilience, scalability; � Distribute the new algorithms and runtime support through widely used software packages; � Establish a strong outreach program to disseminate results, interact with colleagues and train students and junior members of our community.
Date: October 15, 2013
Creator: Dongarra, Jack
Object Type: Report
System: The UNT Digital Library
Characterization Tests of a Stripline Beam Position Monitor for the CLIC Drive Beam (open access)

Characterization Tests of a Stripline Beam Position Monitor for the CLIC Drive Beam

None
Date: October 15, 2013
Creator: Soby, L.; Nappa, J. M.; Tassan-Viol, J.; Vilalte, S.; Faus-Golfe, A.; Garcia-Garrigos, J. J. et al.
Object Type: Article
System: The UNT Digital Library
Dielectric Characterization and Microwave Interferometry in HMX-based Explosives (open access)

Dielectric Characterization and Microwave Interferometry in HMX-based Explosives

None
Date: October 15, 2013
Creator: Tringe, J. W.; Kane, R. J.; Lorenz, K. T.; Baluyot, E. V. & Vandersall, K. S.
Object Type: Article
System: The UNT Digital Library
Effect of Roughness on Emittance of Potassium Cesium Antimonide Photocathodes (open access)

Effect of Roughness on Emittance of Potassium Cesium Antimonide Photocathodes

None
Date: October 15, 2013
Creator: Vecchione, T.; Feng, J.; Wan, W.; Padmore, H. A.; Ben-Zvi, Ilan; Liang, X. et al.
Object Type: Article
System: The UNT Digital Library
Final Report: Large-Scale Optimization for Bayesian Inference in Complex Systems (open access)

Final Report: Large-Scale Optimization for Bayesian Inference in Complex Systems

The SAGUARO (Scalable Algorithms for Groundwater Uncertainty Analysis and Robust Optimiza- tion) Project focuses on the development of scalable numerical algorithms for large-scale Bayesian inversion in complex systems that capitalize on advances in large-scale simulation-based optimiza- tion and inversion methods. Our research is directed in three complementary areas: efficient approximations of the Hessian operator, reductions in complexity of forward simulations via stochastic spectral approximations and model reduction, and employing large-scale optimization concepts to accelerate sampling. Our efforts are integrated in the context of a challenging testbed problem that considers subsurface reacting flow and transport. The MIT component of the SAGUARO Project addresses the intractability of conventional sampling methods for large-scale statistical inverse problems by devising reduced-order models that are faithful to the full-order model over a wide range of parameter values; sampling then employs the reduced model rather than the full model, resulting in very large computational savings. Results indicate little effect on the computed posterior distribution. On the other hand, in the Texas-Georgia Tech component of the project, we retain the full-order model, but exploit inverse problem structure (adjoint-based gradients and partial Hessian information of the parameter-to- observation map) to implicitly extract lower dimensional information on the posterior distribution; …
Date: October 15, 2013
Creator: Ghattas, Omar
Object Type: Report
System: The UNT Digital Library
Future Automotive Aftertreatment Solutions: The 150°C Challenge Workshop Report (open access)

Future Automotive Aftertreatment Solutions: The 150°C Challenge Workshop Report

With future fuel economy standards enacted, the U.S. automotive manufacturers (OEMs) are committed to pursuing a variety of high risk/highly efficient stoichiometric and lean combustion strategies to achieve superior performance. In recognition of this need, the U.S. Department of Energy (DOE) has partnered with domestic automotive manufacturers through U.S. DRIVE to develop these advanced technologies. However, before these advancements can be introduced into the U.S. market, they must also be able to meet increasingly stringent emissions requirements. A significant roadblock to this implementation is the inability of current catalyst and aftertreatment technologies to provide the required activity at the much lower exhaust temperatures that will accompany highly efficient combustion processes and powertrain strategies. Therefore, the goal of this workshop and report is to create a U.S. DRIVE emission control roadmap that will identify new materials and aftertreatment approaches that offer the potential for 90% conversion of emissions at low temperature (150°C) and are consistent with highly efficient combustion technologies currently under investigation within U.S. DRIVE Advanced Combustion and Emission Control (ACEC) programs.
Date: October 15, 2013
Creator: Zammit, Michael; DiMaggio, Craig L.; Kim, Chang H.; Lambert, Christine; Muntean, George G.; Peden, Charles HF et al.
Object Type: Report
System: The UNT Digital Library
Integrated Genome-Based Studies of Shewanella Ecophysiology (open access)

Integrated Genome-Based Studies of Shewanella Ecophysiology

This project had as its goals the understanding of the ecophysiology of the genus Shewanella using various genomics approaches. As opposed to other programs involving Shewanella, this one branched out into the various areas in which Shewanella cells are active, and included both basic and applied studies. All of the work was, to some extent, related to the ability of the bacteria to accomplish electron exchange between the cell and solid state electron acceptors and/or electron donors, a process we call Extracellular Electron Transport, or EET. The major accomplishments related to several different areas: Basic Science Studies: 1. Genetics and genomics of nitrate reduction, resulting in elucidation of atypical nitrate reduction systems in Shewanella oneidensis (MR-1)[2]. 2. Influence of bacterial strain and growth conditions on iron reduction, showing that rates of reduction, extents of reduction, and the formation of secondary minerals were different for different strains of Shewanella [3,4,9]. 3. Comparative genomics as a tool for comparing metabolic capacities of different Shewanella strains, and for predicting growth and metabolism [6,10,15]. In these studies, collaboration with ORNL, PNNL, and 4. Basic studies of electron transport in strain MR-1, both to poised electrodes, and via conductive nanowires [12,13]. This included the first …
Date: October 15, 2013
Creator: Nealson, Kenneth H.
Object Type: Report
System: The UNT Digital Library
Multiphysics Applications of ACE3P (open access)

Multiphysics Applications of ACE3P

None
Date: October 15, 2013
Creator: Lee, Ki H.; Ko, Kwok; Li, Zenghai; Ng, Cho-Kuen; Xiao, Liling; Cheng, G. et al.
Object Type: Article
System: The UNT Digital Library
Polarimetry at RHIC: RHIC polarized beam in Run 2011 (open access)

Polarimetry at RHIC: RHIC polarized beam in Run 2011

N/A
Date: October 15, 2013
Creator: Zelenski, A.
Object Type: Report
System: The UNT Digital Library
Radionuclide Retention in Concrete Wasteforms - FY13 (open access)

Radionuclide Retention in Concrete Wasteforms - FY13

Assessing long-term performance of Category 3 waste cement grouts for radionuclide encasement requires knowledge of the radionuclide-cement interactions and mechanisms of retention (i.e., sorption or precipitation); the mechanism of contaminant release; the significance of contaminant release pathways; how wasteform performance is affected by the full range of environmental conditions within the disposal facility; the process of wasteform aging under conditions that are representative of processes occurring in response to changing environmental conditions within the disposal facility; the effect of wasteform aging on chemical, physical, and radiological properties; and the associated impact on contaminant release. This knowledge will enable accurate prediction of radionuclide fate when the wasteforms come in contact with groundwater. Data collected throughout the course of this work will be used to quantify the efficacy of concrete wasteforms, similar to those used in the disposal of low-level waste and mixed low-level waste, for the immobilization of key radionuclides (i.e., uranium, technetium, and iodine). Data collected will also be used to quantify the physical and chemical properties of the concrete affecting radionuclide retention.
Date: October 15, 2013
Creator: Snyder, Michelle MV; Golovich, Elizabeth C.; Wellman, Dawn M.; Crum, Jarrod V.; Lapierre, Robert; Dage, Denomy C. et al.
Object Type: Report
System: The UNT Digital Library
Resistive Wall Heating of the Undulator in High Repetition Rate FELs (open access)

Resistive Wall Heating of the Undulator in High Repetition Rate FELs

None
Date: October 15, 2013
Creator: Qiang, J.; Corlett, J.N.; Emma, P. & Wu, J.
Object Type: Article
System: The UNT Digital Library
Resonant Spin Depolarisation Measurements at the SPEAR3 Electron Storage Ring (open access)

Resonant Spin Depolarisation Measurements at the SPEAR3 Electron Storage Ring

None
Date: October 15, 2013
Creator: Wootton, K. P.; Boland, M. J.; Rassool, R. P.; Tan, Y.-R. E.; Corbett, W. J.; Donald, M. et al.
Object Type: Article
System: The UNT Digital Library
The RHIC polarized source upgrade (open access)

The RHIC polarized source upgrade

N/A
Date: October 15, 2013
Creator: A., Zelenski; Atoian, G.; Ritter, J.; Steski, D.; Davydenko, V.; Ivanov, A. et al.
Object Type: Report
System: The UNT Digital Library
Single Electron Dynamic of Microwave Undulator (open access)

Single Electron Dynamic of Microwave Undulator

None
Date: October 15, 2013
Creator: Chang, C.; Neilson, J.; Pellegrini, C.; Shumail, M. & Tantawi, S. G.
Object Type: Article
System: The UNT Digital Library
Time-resolved x-ray diffraction across water-ices VI/VII transformations using dynamic-DAC (open access)

Time-resolved x-ray diffraction across water-ices VI/VII transformations using dynamic-DAC

None
Date: October 15, 2013
Creator: Chen, J. Y.; Kim, M.; Yoo, C. & Evans, W. J.
Object Type: Article
System: The UNT Digital Library
Wakefield Calculations for Septum Magnet in LCLS-II (open access)

Wakefield Calculations for Septum Magnet in LCLS-II

None
Date: October 15, 2013
Creator: Bane, K. L. F. & Raubenheimer, T.
Object Type: Article
System: The UNT Digital Library
WET-NZ Multi-Mode Wave Energy Converter Advancement Project (open access)

WET-NZ Multi-Mode Wave Energy Converter Advancement Project

The overall objective of the project was to verify the ocean wavelength functionality of the WET-NZ through targeted hydrodynamic testing at wave tank scale and controlled open sea deployment of a 1/2 scale (1:2) experimental device. This objective was accomplished through a series of tasks designed to achieve four specific goals: Wave Tank Testing to Characterize Hydrodynamic Characteristics;  Open-Sea Testing of a New 1:2 Scale Experimental Model;  Synthesis and Analysis to Demonstrate and Confirm TRL5/6 Status;  Market Impact & Competitor Analysis, Business Plan and Commercialization Strategy.
Date: October 15, 2013
Creator: Kopf, Steven
Object Type: Report
System: The UNT Digital Library
Advanced, Integrated Control for Building Operations to Achieve 40% Energy Saving (open access)

Advanced, Integrated Control for Building Operations to Achieve 40% Energy Saving

we developed and demonstrated a software based integrated advanced building control platform called Smart Energy Box (SEB), which can coordinate building subsystem controls, integrate variety of energy optimization algorithms and provide proactive and collaborative energy management and control for building operations using weather and occupancy information. The integrated control system is a low cost solution and also features: Scalable component based architecture allows to build a solution for different building control system configurations with needed components; Open Architecture with a central data repository for data exchange among runtime components; Extendible to accommodate variety of communication protocols. Optimal building control for central loads, distributed loads and onsite energy resource Uses web server as a loosely coupled way to engage both building operators and building occupants in collaboration for energy conservation. Based on the open platform of SEB, we have investigated and evaluated a variety of operation and energy saving control strategies on Carnegie Mellon University Intelligent Work place which is equipped with alternative cooling/heating/ventilation/lighting methods, including radiant mullions, radiant cooling/heating ceiling panels, cool waves, dedicated ventilation unit, motorized window and blinds, and external louvers. Based on the validation results of these control strategies, they were integrated in SEB in a collaborative …
Date: October 15, 2012
Creator: Dr. Zhen Song, Prof. Vivian Loftness, Dr. Kun Ji, Dr. Sam Zheng, Mr. Bertrand Lasternas, Ms. Flore Marion, Mr. Yuebin Yu
Object Type: Report
System: The UNT Digital Library
Conference on Non-linear Phenomena in Mathematical Physics: Dedicated to Cathleen Synge Morawetz on her 85th Birthday. The Fields Institute, Toronto, Canada September 18-20, 2008. Sponsors: Association for Women in Mathematics, Inc. and The Fields Institute (open access)

Conference on Non-linear Phenomena in Mathematical Physics: Dedicated to Cathleen Synge Morawetz on her 85th Birthday. The Fields Institute, Toronto, Canada September 18-20, 2008. Sponsors: Association for Women in Mathematics, Inc. and The Fields Institute

This scientific meeting focused on the legacy of Cathleen S. Morawetz and the impact that her scientific work on transonic flow and the non-linear wave equation has had in recent progress on different aspects of analysis for non-linear wave, kinetic and quantum transport problems associated to mathematical physics. These are areas where the elements of continuum, statistical and stochastic mechanics, and their interplay, have counterparts in the theory of existence, uniqueness and stability of the associated systems of equations and geometric constraints. It was a central event for the applied and computational analysis community focusing on Partial Differential Equations. The goal of the proposal was to honor Cathleen Morawetz, a highly successful woman in mathematics, while encouraging beginning researchers. The conference was successful in show casing the work of successful women, enhancing the visibility of women in the profession and providing role models for those just beginning their careers. The two-day conference included seven 45-minute lectures and one day of six 45-minute lectures, and a poster session for junior participants. The conference program included 19 distinguished speakers, 10 poster presentations, about 70 junior and senior participants and, of course, the participation of Cathleen Synge Morawetz. The conference celebrated Morawetz’s paramount …
Date: October 15, 2012
Creator: Lewis, Jennifer
Object Type: Report
System: The UNT Digital Library
Development of Single Crystal Chemical Vapor Deposition Diamonds for Detector Applications (open access)

Development of Single Crystal Chemical Vapor Deposition Diamonds for Detector Applications

Diamond was studied as a possible radiation hard technology for use in future high radiation environments. With the commissioning of the LHC expected in 2010, and the LHC upgrades expected in 2015, all LHC experiments are planning for detector upgrades which require radiation hard technologies. Chemical Vapor Deposition (CVD) diamond has now been used extensively in beam conditions monitors as the innermost detectors in the highest radiation areas of BaBar, Belle and CDF and is installed and operational in all LHC experiments. As a result, this material is now being discussed as an alternative sensor material for tracking very close to the interaction region of the super-LHC where the most extreme radiation conditions will exist. Our work addressed the further development of the new material, single-crystal Chemical Vapor Deposition diamond, towards reliable industrial production of large pieces and new geometries needed for detector applications.
Date: October 15, 2012
Creator: Wallny, Rainer
Object Type: Report
System: The UNT Digital Library
Dynamical Spin Susceptibility in the TD-LDA and QSGW Approximations (open access)

Dynamical Spin Susceptibility in the TD-LDA and QSGW Approximations

Abstract. This project was aimed at building the transverse dynamical spin susceptibility with the TD-LDA and the recently-developed Quasparticle Self-Consisent Approximations, which determines an optimum quasiparticle picture in a self-consistent manner within the GW approximation. Our main results were published into two papers, (J. Phys. Cond. Matt. 20, 95214 (2008), and Phys. Rev. B83, 060404(R) (2011). In the first paper we present spin wave dispersions for MnO, NiO, and #11;-MnAs based on quasiparticle self-consistent GW approximation (QSGW). For MnO and NiO, QSGW results are in rather good agreement with experiments, in contrast to the LDA and LDA+U descriptions. For #11;-MnAs, we find a collinear ferromagnetic ground state in QSGW, while this phase is unstable in the LDA. In the second, we apply TD-LDA to the CaFeAs2 — the first attempt the first ab initio calculation of dynamical susceptibililty in a system with complex electronic structure Magnetic excitations in the striped phase of CaFe2As2 are studied as a function of local moment amplitude. We find a new kind of excitation: sharp resonances of Stoner-like (itinerant) excitations at energies comparable to the N´eel temperature, originating largely from a narrow band of Fe d states near the Fermi level, and coexisting with more …
Date: October 15, 2012
Creator: van Schilfgaarde, Mark & Kotani, Takao
Object Type: Report
System: The UNT Digital Library
Fast Beam-Based BPM Calibration (open access)

Fast Beam-Based BPM Calibration

The Alignment Diagnostic System (ADS) of the LCLS undulator system indicates that the 33 undulator quadrupoles have extremely high position stability over many weeks. However, beam trajectory straightness and lasing efficiency degrade more quickly than this. A lengthy Beam Based Alignment (BBA) procedure must be executed every two to four weeks to re-optimize the X-ray beam parameters. The undulator system includes RF cavity Beam Position Monitors (RFBPMs), several of which are utilized by an automatic feedback system to align the incoming electron-beam trajectory to the undulator axis. The beam trajectory straightness degradation has been traced to electronic drifts of the gain and offset of the BPMs used in the beam feedback system. To quickly recover the trajectory straightness, we have developed a fast beam-based procedure to recalibrate the BPMs. This procedure takes advantage of the high-precision monitoring capability of the ADS, which allows highly repeatable positioning of undulator quadrupoles. This report describes the ADS, the position stability of the LCLS undulator quadrupoles, and some results of the new recovery procedure.
Date: October 15, 2012
Creator: Bertsche, K.; Loos, H.; Nuhn, H. D. & Peters, F.
Object Type: Article
System: The UNT Digital Library
Final Technical Report: Grain Boundary Complexions and Transitions in Doped Silicon (open access)

Final Technical Report: Grain Boundary Complexions and Transitions in Doped Silicon

This four-year research project has advanced the fundamental knowledge of grain boundary (GB) complexions (i.e., "two-dimensional interfacial phases") and associated GB "phase" transitions in several grounds. First, a bilayer interfacial phase, which had been directly observed by microscopy only in complex ceramic systems in prior studies, has been identified in simpler systems such as Au-doped Si and Bi-doped Ni in this study, where the interpretations of the their formation mechanisms and microscopic images are less equivocal. Second, convincing evidence for the existence of a first-order GB transition from a nominally "clean" GB to a bilayer adsorption interfacial phase has been revealed for Au-doped Si; the confirmation of the first-order nature of interfacial transitions at GBs, which was rare in prior studies, is scientifically significant and technologically important. Third, the bilayer interfacial phase discovered in Bi-doped Ni has been found to be the cause of the mysterious liquid metal embrittlement phenomenon in this system; the exact atomic level mechanism of this phenomenon has puzzled the materials and physics communities for over a century. Finally, significant advancements have been made to establish phenomenological thermodynamic models for GB complexions and transitions. Since GB complexions can control the transport, mechanical and physical properties of …
Date: October 15, 2012
Creator: Luo, Jian
Object Type: Report
System: The UNT Digital Library