The Application of Range Space Operations to Color Images (open access)

The Application of Range Space Operations to Color Images

The knowledge gained from scientific observation, experiment, and simulation is linked to the ability to analyze, understand, and manage the generated results. These abilities are increasingly at odds with the current, and future, capabilities to generate enormous quantities of raw scientific and engineering data from instruments, sensors, and computers. Many researchers are currently engaged in activities that seek to create new and novel methods for analyzing, understanding, and managing these vast collections of data. In this work, we present some of our research in addressing a particular type of problem in this broad undertaking. Much the scientific data of interest is in the form of observed, measured, or computed multivariate or multi-component vector field data--with either as physical or color data values. We are currently researching methods and techniques for working with this type of vector data through the use of a novel analysis technique. Our basic approach is to work with the vector field data in its natural physical or color space. When the data is viewed as a functional mapping of a domain, usually an index space, to a range, the physical or color values, potentially interesting characteristics of the data present themselves. These characteristics are useful in …
Date: March 26, 2002
Creator: Baldwin, Chuck & Duchaineau, Mark
System: The UNT Digital Library
Iron-Based Amorphous Coatings Produced by HVOF Thermal Spray Processing-Coating Structure and Properties (open access)

Iron-Based Amorphous Coatings Produced by HVOF Thermal Spray Processing-Coating Structure and Properties

The feasibility to coat large SNF/HLW containers with a structurally amorphous material (SAM) was demonstrated on sub-scale models fabricated from Type 316L stainless steel. The sub-scale model were coated with SAM 1651 material using kerosene high velocity oxygen fuel (HVOF) torch to thicknesses ranging from 1 mm to 2 mm. The process parameters such as standoff distance, oxygen flow, and kerosene flow, were optimized in order to improve the corrosion properties of the coatings. Testing in an electrochemical cell and long-term exposure to a salt spray environment were used to guide the selection of process parameters.
Date: March 26, 2008
Creator: Beardsley, M B
System: The UNT Digital Library
Active control for turbulent premixed flame simulations (open access)

Active control for turbulent premixed flame simulations

Many turbulent premixed flames of practical interest are statistically stationary. They occur in combustors that have anchoring mechanisms to prevent blow-off and flashback. The stabilization devices often introduce a level of geometric complexity that is prohibitive for detailed computational studies of turbulent flame dynamics. As a result, typical detailed simulations are performed in simplified model configurations such as decaying isotropic turbulence or inflowing turbulence. In these configurations, the turbulence seen by the flame either decays or, in the latter case, increases as the flame accelerates toward the turbulent inflow. This limits the duration of the eddy evolutions experienced by the flame at a given level of turbulent intensity, so that statistically valid observations cannot be made. In this paper, we apply a feedback control to computationally stabilize an otherwise unstable turbulent premixed flame in two dimensions. For the simulations, we specify turbulent in flow conditions and dynamically adjust the integrated fueling rate to control the mean location of the flame in the domain. We outline the numerical procedure, and illustrate the behavior of the control algorithm. We use the simulations to study the propagation and the local chemical variability of turbulent flame chemistry.
Date: March 26, 2004
Creator: Bell, John B.; Day, Marcus S.; Grcar, Joseph F. & Lijewski, Michael J.
System: The UNT Digital Library
Parallelizing a High Accuracy Hardware-Assisted Volume Renderer for Meshes with Arbitrary Polyhedra (open access)

Parallelizing a High Accuracy Hardware-Assisted Volume Renderer for Meshes with Arbitrary Polyhedra

This paper discusses the authors efforts to improve the performance of the high-accuracy (HIAC) volume rendering system, based on cell projection, which is used to display unstructured, scientific data sets for analysis. The parallelization of HIAC, using the pthreads and MPI API's, resulted in significant speedup, but interactive frame rates are not yet attainable for very large data sets.
Date: March 26, 2001
Creator: Bennett, J.; Cook, R.; Max, N.; May, D. & Williams, P.
System: The UNT Digital Library
Dynamic effects in fragmentation reactions. (open access)

Dynamic effects in fragmentation reactions.

Fragmentation reactions offer a useful tool to study the spectroscopy of halo nuclei, but the large extent of the halo wave function makes the reaction theory more difficult. The simple reaction models based on the eikonal approximation for the nuclear interaction or first-order perturbation theory for the Coulomb interaction have systematic errors that they investigate here, comparing to the predictions of complete dynamical calculations. They find that stripping probabilities are underpredicted by the eikonal model, leading to extracted spectroscopy strengths that are two large. In contrast, the Coulomb excitation is overpredicted by the simple theory. They attribute this to a screening effect, as is well known in the Barkas effect on stopping powers. The errors decrease with beam energy as E{sub beam}{sup -1}, and are not significant at beam energies above 50 MeV/u. At lower beam energies, the effects should be taken into account when extracting quantitative spectroscopic strengths.
Date: March 26, 2002
Creator: Bertsch, G. F. & Esbensen, H.
System: The UNT Digital Library
Creating interoperable meshing and discretization software : the terascale simulation tools and technology center. (open access)

Creating interoperable meshing and discretization software : the terascale simulation tools and technology center.

The authors present an overview of the technical objectives of the Terascale Simulation Tools and Technologies center. The primary goal of this multi-institution collaboration is to develop technologies that enable application scientists to easily use multiple mesh and discretization strategies within a single simulation on terascale computers. The discussion focuses on the efforts to create interoperable mesh generation tools, high-order discretization techniques, and adaptive meshing strategies.
Date: March 26, 2002
Creator: Brown, D.; Freitag, L. & Glimm, J.
System: The UNT Digital Library
Sequential Model-Based Detection in a Shallow Ocean Acoustic Environment (open access)

Sequential Model-Based Detection in a Shallow Ocean Acoustic Environment

A model-based detection scheme is developed to passively monitor an ocean acoustic environment along with its associated variations. The technique employs an embedded model-based processor and a reference model in a sequential likelihood detection scheme. The monitor is therefore called a sequential reference detector. The underlying theory for the design is developed and discussed in detail.
Date: March 26, 2002
Creator: Candy, J V
System: The UNT Digital Library
Adaptive Sampling for Noisy Problems (open access)

Adaptive Sampling for Noisy Problems

The usual approach to deal with noise present in many real-world optimization problems is to take an arbitrary number of samples of the objective function and use the sample average as an estimate of the true objective value. The number of samples is typically chosen arbitrarily and remains constant for the entire optimization process. This paper studies an adaptive sampling technique that varies the number of samples based on the uncertainty of deciding between two individuals. Experiments demonstrate the effect of adaptive sampling on the final solution quality reached by a genetic algorithm and the computational cost required to find the solution. The results suggest that the adaptive technique can effectively eliminate the need to set the sample size a priori, but in many cases it requires high computational costs.
Date: March 26, 2004
Creator: Cantu-Paz, E
System: The UNT Digital Library
Book Review Geostatistical Analysis of Compositional Data (open access)

Book Review Geostatistical Analysis of Compositional Data

Compositional data are represented as vector variables with individual vector components ranging between zero and a positive maximum value representing a constant sum constraint, usually unity (or 100 percent). The earth sciences are flooded with spatial distributions of compositional data, such as concentrations of major ion constituents in natural waters (e.g. mole, mass, or volume fractions), mineral percentages, ore grades, or proportions of mutually exclusive categories (e.g. a water-oil-rock system). While geostatistical techniques have become popular in earth science applications since the 1970s, very little attention has been paid to the unique mathematical properties of geostatistical formulations involving compositional variables. The book 'Geostatistical Analysis of Compositional Data' by Vera Pawlowsky-Glahn and Ricardo Olea (Oxford University Press, 2004), unlike any previous book on geostatistics, directly confronts the mathematical difficulties inherent to applying geostatistics to compositional variables. The book righteously justifies itself with prodigious referencing to previous work addressing nonsensical ranges of estimated values and error, spurious correlation, and singular cross-covariance matrices.
Date: March 26, 2007
Creator: Carle, S F
System: The UNT Digital Library
Delamination Failure Investigation for Out-Of-Plane Loading in Laminates (open access)

Delamination Failure Investigation for Out-Of-Plane Loading in Laminates

In contrast to failure approaches at the lamina level or the micromechanics level the present work concerns failure characterization at the laminate level. Specifically, attention is given to the ultimate failure characterization for quasi-isotropic laminates. This is in further contrast to the commonly used approaches for initial damage or progressive damage. It is shown that the analytical failure forms decompose into two modes, one for out of plane, delamination type failure and one for in plane, fiber controlled type failure. The work here is mainly given over to the delamination mode of failure. Experimental results are presented for laminates in this mode of failure. These results are then integrated with the analytical forms to give a simple criterion for delamination failure.
Date: March 26, 2003
Creator: Christensen, R M & DeTeresa, S J
System: The UNT Digital Library
Large-timestep mover for particle simulations of arbitrarilymagnetized species (open access)

Large-timestep mover for particle simulations of arbitrarilymagnetized species

For self-consistent ion-beam simulations including electron motion, it is desirable to be able to follow electron dynamics accurately without being constrained by the electron cyclotron timescale. To this end, we have developed a particle-advance that interpolates between full particle dynamics and drift motion. By making a proper choice of interpolation parameter, simulation particles experience physically correct parallel dynamics, drift motion, and gyroradius when the timestep is large compared to the cyclotron period, though the effective gyro frequency is artificially low; in the opposite timestep limit, the method approaches a conventional Boris particle push. By combining this scheme with a Poisson solver that includes an interpolated form of the polarization drift in the dielectric response, the movers utility can be extended to higher-density problems where the plasma frequency of the species being advanced exceeds its cyclotron frequency. We describe a series of tests of the mover and its application to simulation of electron clouds in heavy-ion accelerators.
Date: March 26, 2007
Creator: Cohen, R. H.; Friedman, A.; Grote, D. P. & Vay, J. L.
System: The UNT Digital Library
Efficiently Sorting Zoo-Mesh Data Sets (open access)

Efficiently Sorting Zoo-Mesh Data Sets

The authors describe the SXMPVO algorithm for performing a visibility ordering zoo-meshed polyhedra. The algorithm runs in practice in linear time and the visibility ordering which it produces is exact.
Date: March 26, 2001
Creator: Cook, R.; Max, N.; Silva, C. & Williams, P.
System: The UNT Digital Library
Calibration of the HB line active well neutron coincidence counter for measurement of LANL 3013 highly enriched uranium product splits (open access)

Calibration of the HB line active well neutron coincidence counter for measurement of LANL 3013 highly enriched uranium product splits

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Date: March 26, 2008
Creator: Dewberry, R.; Williams, D. R.; Lee, R. S.; Roberts, D. W.; Arrigo, L. M. & Salaymeh, S. R.
System: The UNT Digital Library
Determination of the Evaporation Coefficient of D2O (open access)

Determination of the Evaporation Coefficient of D2O

The evaporation rate of D{sub 2}O has been determined by Raman thermometry of a droplet train (12-15 {micro}m diameter) injected into vacuum ({approx}10{sup -5} torr). The cooling rate measured as a function of time in vacuum was fit to a model that accounts for temperature gradients between the surface and the core of the droplets, yielding an evaporation coefficient ({gamma}{sub e}) of 0.57 {+-} 0.06. This is nearly identical to that found for H{sub 2}O (0.62 {+-} 0.09) using the same experimental method and model, and indicates the existence of a kinetic barrier to evaporation. The application of a recently developed transition state theory (TST) model suggests that the kinetic barrier is due to librational and hindered translational motions at the liquid surface, and that the lack of an isotope effect is due to competing energetic and entropic factors. The implications of these results for cloud and aerosol particles in the atmosphere are discussed.
Date: March 26, 2008
Creator: Drisdell, Walter S.; Cappa, Christopher D.; Smith, Jared D.; Saykally, Richard J. & Cohen, Ronald C.
System: The UNT Digital Library
The Mercury Laser System-A scaleable average-power laser for fusion and beyond (open access)

The Mercury Laser System-A scaleable average-power laser for fusion and beyond

Nestled in a valley between the whitecaps of the Pacific and the snowcapped crests of the Sierra Nevada, Lawrence Livermore National Laboratory (LLNL) is home to the nearly complete National Ignition Facility (NIF). The purpose of NIF is to create a miniature star-on demand. An enormous amount of laser light energy (1.8 MJ in a pulse that is 20 ns in duration) will be focused into a small gold cylinder approximately the size of a pencil eraser. Centered in the gold cylinder (or hohlraum) will be a nearly perfect sphere filled with a complex mixture of hydrogen gas isotopes that is similar to the atmosphere of our Sun. During experiments, the laser light will hit the inside of the gold cylinder, heating the metal until it emits X-rays (similar to how your electric stove coil emits visible red light when heated). The X-rays will be used to compress the hydrogen-like gas with such pressure that the gas atoms will combine or 'fuse' together, producing the next heavier element (helium) and releasing energy in the form of energetic particles. 2010 will mark the first credible attempt at this world-changing event: the achievement of fusion energy 'break-even' on Earth using NIF, the …
Date: March 26, 2008
Creator: Ebbers, C A & Moses, E I
System: The UNT Digital Library
Reconstruction of mechanically recorded sound by image processing (open access)

Reconstruction of mechanically recorded sound by image processing

Audio information stored in the undulations of grooves in a medium such as a phonograph record may be reconstructed, with no or minimal contact, by measuring the groove shape using precision metrology methods and digital image processing. The effects of damage, wear, and contamination may be compensated, in many cases, through image processing and analysis methods. The speed and data handling capacity of available computing hardware make this approach practical. Various aspects of this approach are discussed. A feasibility test is reported which used a general purpose optical metrology system to study a 50 year old 78 r.p.m. phonograph record. Comparisons are presented with stylus playback of the record and with a digitally re-mastered version of the original magnetic recording. A more extensive implementation of this approach, with dedicated hardware and software, is considered.
Date: March 26, 2003
Creator: Fadeyev, Vitaliy & Haber, Carl
System: The UNT Digital Library
Proteins as paradigms of complex systems. (open access)

Proteins as paradigms of complex systems.

The science of complexity has moved to center stage within the past few decades. Complex systems range from glasses to the immune system and the brain. Glasses are too simple to possess all aspects of complexity; brains are too complex to expose common concepts and laws of complexity. Proteins, however, are systems where many concepts and laws of complexity can be explored experimentally, theoretically, and computationally. Such studies have elucidated crucial aspects. The energy landscape has emerged as one central concept; it describes the free energy of a system as a function of temperature and the coordinates of all relevant atoms. A second concept is that of fluctuations. Without fluctuations, proteins would be dead and life impossible. A third concept is slaving. Proteins are not isolated systems; they are embedded in cells and membranes. Slaving arises when the fluctuations in the surroundings of a protein dominate many of the motions of the protein proper.
Date: March 26, 2003
Creator: Fenimore, Paul W.; Frauenfelder, Hans & Young, Robert D.
System: The UNT Digital Library
MESQUITE design : issues in the development of a mesh quality improvement toolkit. (open access)

MESQUITE design : issues in the development of a mesh quality improvement toolkit.

Poor mesh quality is known to adversely affect both solution efficiency and accuracy. There has been considerable research on a wide variety of mesh improvement algorithms, but the impact of these algorithms on applications has been limited because they are typically embedded in particular meshing software packages. To rectify this situation, they are developing a stand-alone mesh quality improvement toolkit called MESQUITE. In this paper, the authors describe the motivation, goals, and design of MESQUITE and give some computational results using the underlying algorithms that show the benefit of such a package.
Date: March 26, 2002
Creator: Freitag, L.; Leurent, T.; Knupp, P. & Melander, D.
System: The UNT Digital Library
Colliding with a crunching bubble (open access)

Colliding with a crunching bubble

In the context of eternal inflation we discuss the fate of Lambda = 0 bubbles when they collide with Lambda< 0 crunching bubbles. When the Lambda = 0 bubble is supersymmetric, it is not completely destroyed by collisions. If the domain wall separating the bubbles has higher tension than the BPS bound, it is expelled from the Lambda = 0 bubble and does not alter its long time behavior. If the domain wall saturates the BPS bound, then it stays inside the Lambda = 0 bubble and removes a finite fraction of future infinity. In this case, the crunch singularity is hidden behind the horizon of a stable hyperbolic black hole.
Date: March 26, 2007
Creator: Freivogel, Ben; Freivogel, Ben; Horowitz, Gary T. & Shenker, Stephen
System: The UNT Digital Library
Analyzing water/wastewater infrastructure interdependencies. (open access)

Analyzing water/wastewater infrastructure interdependencies.

This paper describes four general categories of infrastructure interdependencies (physical, cyber, geographic, and logical) as they apply to the water/wastewater infrastructure, and provides an overview of one of the analytic approaches and tools used by Argonne National Laboratory to evaluate interdependencies. Also discussed are the dimensions of infrastructure interdependency that create spatial, temporal, and system representation complexities that make analyzing the water/wastewater infrastructure particularly challenging. An analytical model developed to incorporate the impacts of interdependencies on infrastructure repair times is briefly addressed.
Date: March 26, 2002
Creator: Gillette, J. L.; Fisher, R. E.; Peerenboom, J. P. & Whitfield, R. G.
System: The UNT Digital Library
Visual Analysis of Weblog Content (open access)

Visual Analysis of Weblog Content

In recent years, one of the advances of the World Wide Web is social media and one of the fastest growing aspects of social media is the blogosphere. Blogs make content creation easy and are highly accessible through web pages and syndication. With their growing influence, a need has arisen to be able to monitor the opinions and insight revealed within their content. In this paper we describe a technical approach for analyzing the content of blog data using a visual analytic tool, IN-SPIRE, developed by Pacific Northwest National Laboratory. We highlight the capabilities of this tool that are particularly useful for information gathering from blog data.
Date: March 26, 2007
Creator: Gregory, Michelle L.; Payne, Deborah A.; McColgin, Dave; Cramer, Nick O. & Love, Douglas V.
System: The UNT Digital Library
Development of Hfe Sections of Dg-1145. (open access)

Development of Hfe Sections of Dg-1145.

For the licensing of the current fleet of commercial nuclear power plants (NPPs), the Nuclear Regulatory Commission (NRC) used two key documents, NUREG-0800 and Regulatory Guide (RG) 1.70. RG 1.70 provided guidance to applicants on the contents needed in their Safety Analysis Reports (SARs) submitted as part of their application to construct or operate an NPP. NUREG-0800, the NRC Standard Review Plan (SRP), provides guidance to the NRR staff reviewers on performing their safety reviews of these applications. As part of the preparation for a new wave of improved NPP designs the NRC is in the process of updating the SRP and is also developing a new RG designated as draft RG or DG-1145, ''Combined License Applications for Nuclear Power Plants (LWR Edition).'' This will eventually become RG 1.206 and will take the place of RG 1.70. This will provide guidance for combined license (COL) applicants, as well as for other 10CFR Part 52 variations that are permitted.
Date: March 26, 2007
Creator: Higgins, J. C.; Ohara, J. M. & Bongarra, J.
System: The UNT Digital Library
Materials for solid state lighting (open access)

Materials for solid state lighting

Dramatic improvement in the efficiency of inorganic and organic light emitting diodes (LEDs and OLEDs) within the last decade has made these devices viable future energy efficient replacements for current light sources. However, both technologies must overcome major technical barriers, requiring significant advances in material science, before this goal can be achieved. Attention will be given to each technology associated with the following major areas of material research: (1) material synthesis, (2) process development, (3) device and defect physics, and (4) packaging. The discussion on material synthesis will emphasize the need for further development of component materials, including substrates and electrodes, necessary for improving device performance. The process technology associated with the LEDs and OLEDs is very different, but in both cases it is one factor limiting device performance. Improvements in process control and methodology are expected to lead to additional benefits of higher yield, greater reliability and lower costs. Since reliability and performance are critical to these devices, an understanding of the basic physics of the devices and device failure mechanisms is necessary to effectively improve the product. The discussion will highlight some of the more basic material science problems remaining to be solved. In addition, consideration will be …
Date: March 26, 2002
Creator: Johnson, S.G. & Simmons, J.A.
System: The UNT Digital Library
LATTICE SIMULATIONS OF THE THERMODYNAMICS OF STRONGLY INTERACTING ELEMENTARY PARTICLES AND THE EXPLORATION OF NEW PHASES OF MATTER IN RELATIVISTIC HEAVY ION COLLISIONS. (open access)

LATTICE SIMULATIONS OF THE THERMODYNAMICS OF STRONGLY INTERACTING ELEMENTARY PARTICLES AND THE EXPLORATION OF NEW PHASES OF MATTER IN RELATIVISTIC HEAVY ION COLLISIONS.

At high temperatures or densities matter formed by strongly interacting elementary particles (hadronic matter) is expected to undergo a transition to a new form of matter--the quark gluon plasma--in which elementary particles (quarks and gluons) are no longer confined inside hadrons but are free to propagate in a thermal medium much larger in extent than the typical size of a hadron. The transition to this new form of matter as well as properties of the plasma phase are studied in large scale numerical calculations based on the theory of strong interactions--Quantum Chromo Dynamics (QCD). Experimentally properties of hot and dense elementary particle matter are studied in relativistic heavy ion collisions such as those currently performed at the relativistic heavy ion collider (RHIC) at BNL. We review here recent results from studies of thermodynamic properties of strongly interacting elementary particle matter performed on Teraflops-Computer. We present results on the QCD equation of state and discuss the status of studies of the phase diagram at non-vanishing baryon number density.
Date: March 26, 2006
Creator: Karsch, F.
System: The UNT Digital Library