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DATA MINING AT THE NEBRASKA OIL & GAS COMMISSION

Description: The purpose of this study of the hearing records is to identify factors that are likely to impact the performance of a waterflood in the Nebraska panhandle. The records consisted of 140 cases. Most of the hearings were held prior to 1980. Many of the records were incomplete, and data believed to be key to estimating waterflood performance such as Dykstra-Parson permeability distribution or relative permeability were absent. New techniques were applied to analyze the sparse, incomplete dataset. When information is available, but not clearly understood, new computational intelligence tools can decipher correlations in the dataset. Fuzzy ranking and neural networks were the tools used to estimate secondary recovery from the Cliff Farms Unit. The hearing records include 30 descriptive entries that could influence the success or failure of a waterflood. Success or failure is defined by the ratio of secondary to primary oil recovery (S/P). Primary recovery is defined as cumulative oil produced at the time of the hearing and secondary recovery is defined as the oil produced since the hearing date. Fuzzy ranking was used to prioritize the relevance of 6 parameters on the outcome of the proposed waterflood. The 6 parameters were universally available in 44 of the case hearings. These 44 cases serve as the database used to correlate the following 6 inputs with the respective S/P. (1) Cumulative Water oil ratio, bbl/bbl; (2) Cumulative Gas oil ratio, mcf/bbl; (3) Unit area, acres; (4) Average Porosity, %; (5) Average Permeability, md; (6) Initial bottom hole pressure, psi. A 6-3-1 architecture describes the neural network used to develop a correlation between the 6 input parameters and their respective S/P. The network trained to a 85% correlation coefficient. The predicted Cliff Farms Unit S/P is 0.315 or secondary recovery is expected to be 102,700 bbl.
Date: May 1, 2001
Creator: Weber, James R.
Partner: UNT Libraries Government Documents Department

High-level core sample x-ray imaging at the Hanford Site

Description: Waste tank sampling of radioactive high-level waste is required for continued operations, waste characterization, and site safety. Hanford Site tank farms consist of 28 double-shell and 149 single-shell underground storage tanks. The single shell tanks are out-of-service an no longer receive liquid waste. Core samples of salt cake and sludge waste are remotely obtained using truck-mounted, core drill platforms. Samples are recovered from tanks through a 2.25 inch (in.) drill pipe in 26-in. steel tubes, 1.5 in. diameter. Drilling parameters vary with different waste types. Because sample recovery has been marginal an inadequate at times, a system was needed to provide drill truck operators with ``real-time feedback`` about the physical condition of the sample and the percent recovery, prior to making nuclear assay measurements and characterizations at the analytical laboratory. The Westinghouse Hanford Company conducted proof-of-principal radiographic testing to verify the feasibility of a proposed imaging system. Tests were conducted using an iridium 192 radiography source to determine the effects of high radiation on image quality. The tests concluded that samplers with a dose rate in excess of 5000 R/hr could be imaged with only a slight loss of image quality and samples less than 1000 R/hr have virtually no effect on image quality. The Mobile Core Sample X-Ray Examination System, a portable vendor-engineered assembly, has components uniquely configured to produce a real-time radiographic system suitable for safely examining radioactive tank core segments collected at the Hanford Site. The radiographic region of interest extends from the bottom (valve) of the sampler upward 19 to 20 in. The purpose of the Mobile Core Sample X-Ray Examination System is to examine the physical contents of core samples after removal from the tank and prior to placement in an onsite transfer cask.
Date: October 1, 1995
Creator: Weber, J. R. & Keve, J.K.
Partner: UNT Libraries Government Documents Department

Waste receiving and processing module 2A mixing tests status report

Description: The purpose of this report is to document the Phase II test conditions, observations, and results of this work. This report provides additional mixing performance test data and rheologic data that provide further indications that there are clear and distinct advantages in the preliminary choice of high-shear mixing alone, and high-shear dispersion in combination with, or followed by, a low-speed type mixer/stirrer for WRAP 2A facility design. Another objective was to determine if significant scale-up problems might exist in the various mix and mixer designs. In the later Phase 2 tests the test material quantities were significantly larger than in the Phase 1 tests.
Date: November 18, 1994
Creator: Weber, J. R. & Hull, K. J.
Partner: UNT Libraries Government Documents Department

Testing and evaluation of alternative process systems for immobilizing radioactive mixed particulate waste in cement

Description: Radioactive and Hazardous Mixed Wastes have accumulated at the Department of Energy (DOE) Hanford Site in south-central Washington State. Ongoing operations and planned facilities at Hanford will also contribute to this waste stream. To meet the Resource Conservation and Recovery Act (RCRA) Land Disposal Restrictions most of this waste will need to be treated to permit disposal. In general this treatment will need to include stabilization/solidification either as a sole method or as part of a treatment train. A planned DOE facility, the Waste Receiving and Processing (WRAP) Module 2A, is scoped to provide this required treatment for containerized contact-handled (CH), mixed low-level waste (MLLW) at Hanford. An engineering development program has been conducted by Westinghouse Hanford Company (WHC) to select the best system for utilizing a cement based process in WRAP Module 2A. Three mixing processes were developed for analysis and testing; in-drum mixing, continuous mixing, and batch mixing. Some full scale tests were conducted and 55 gallon drums of solidified product were produced. These drums were core sampled and examined to evaluate mixing effectiveness. Total solids loading and the order of addition of waste and binder constituents were also varied. The highest confidence approach to meet the WRAP Module 2A waste immobilization system needs appears to be the out-of-drum batch mixing concept. This system is believed to offer the most flexibility and efficiency, given the highly variable and troublesome waste streams feeding the facility.
Date: March 1, 1994
Creator: Weingardt, K. M. & Weber, J. R.
Partner: UNT Libraries Government Documents Department

Influence of the Richtmyer-Meshkov instability on the kinetic energy spectrum.

Description: The fluctuating kinetic energy spectrum in the region near the Richtmyer-Meshkov instability (RMI) is experimentally investigated using particle image velocimetry (PIV). The velocity field is measured at a high spatial resolution in the light gas to observe the effects of turbulence production and dissipation. It is found that the RMI acts as a source of turbulence production near the unstable interface, where energy is transferred from the scales of the perturbation to smaller scales until dissipation. The interface also has an effect on the kinetic energy spectrum farther away by means of the distorted reflected shock wave. The energy spectrum far from the interface initially has a higher energy content than that of similar experiments with a flat interface. These differences are quick to disappear as dissipation dominates the flow far from the interface.
Date: September 1, 2010
Creator: Weber, Christopher R. (University of Wisconsin-Madison, Madison, WI)
Partner: UNT Libraries Government Documents Department

Experimental investigation of the Richtmyer-Meshkov instability.

Description: The Richtmyer-Meshkov instability (RMI) is experimentally investigated using several different initial conditions and with a range of diagnostics. First, a broadband initial condition is created using a shear layer between helium+acetone and argon. The post-shocked turbulent mixing is investigated using planar laser induced fluorescence (PLIF). The signature of turbulent mixing is present in the appearance of an inertial range in the mole fraction energy spectrum and the isotropy of the late-time dissipation structures. The distribution of the mole fraction values does not appear to transition to a homogeneous mixture, and it is possible that this effect may be slow to develop for the RMI. Second, the influence of the RMI on the kinetic energy spectrum is investigated using particle image velocimetry (PIV). The influence of the perturbation is visible relatively far from the interface when compared to the energy spectrum of an initially flat interface. Closer to the perturbation, an increase in the energy spectrum with time is observed and is possibly due to a cascade of energy from the large length scales of the perturbation. Finally, the single mode perturbation growth rate is measured after reshock using a new high speed imaging technique. This technique produced highly time-resolved interface position measurements. Simultaneous measurements at the spike and bubble location are used to compute a perturbation growth rate history. The growth rates from several experiments are compared to a new reshock growth rate model.
Date: September 1, 2011
Creator: Weber, Christopher R. (University of Wisconsin-Madison, Madison, WI)
Partner: UNT Libraries Government Documents Department

Guidelines A Primer for Communicating Effectively with NABIR Stakeholders

Description: The purpose of this report is to help scientists communicate with stakeholders and the public (primarily nonscientists) about fundamental science research. The primary audience for this report is scientists involved in the Natural and Accelerated Bioremediation Research (NABIR) program of the U.S. Department of Energy. However, the information and insights in the report that are not program-specific should be helpful to scientists in other fundamental science research programs. The report first discusses why scientists should talk to stakeholders and the public, and the challenges associated with discussing the NABIR program. It is observed that communication initiatives can be characterized by three factors: relationships in the social environment, views of what constitutes communication, and accepted forms of communication practices and products. With a focus on informal science communication, recent efforts to gauge public understanding of science and the factors that affect public trust of science institutions are discussed. The social bases for scientist-nonscientist interactions are then examined, including possible sources of distrust and difficulties in transferring discussions of fundamental science from classrooms (where most of the public first learns about science) to public forums. Finally, the report contains specific suggestions for preparing, meeting, and following up on public interactions with stakeholders and the public, including themes common to public discussions of NABIR science and features of scientist-nonscientist interactions observed in interpersonal, small group, and large group interactions between NABIR scientists and stakeholders. A Quick Preparation Guide for Meeting NABIR Stakeholders is provided immediately following the Summary. It condenses some of the information and advice found in the text of the report.
Date: March 15, 2002
Creator: Weber, James R.; Word, Charlotte J. & Bilyard, Gordon R.
Partner: UNT Libraries Government Documents Department

Guidelines - A Primer for Communicating Effectively with NABIR Stakeholders

Description: This version of the communication primer comprises two interlocking parts: Pat 1, a practical section, intended to prepare you for public interactions, and Part 2, a theoretical section that provides social and technical bases for the practices recommended in Part 1. The mutual support of practice and theory is very familiar in science and clearly requires a willingness to observe and revise our prior assumptions--in this document, we invoke both. We hope that is offering will represent a step both towards improving practice and maturing the theory of practical science communication.
Date: February 10, 2004
Creator: Weber, James R.; Schell, Charlotte J.; Marino, T & Bilyard, Gordon R.
Partner: UNT Libraries Government Documents Department

Guidelines - A Primer for Communicating Effectively with NABIR Stakeholders

Description: This primer is a tool to help prepare scientists for meetings with stakeholders. It was prepared for staff involved with the Natural and Accelerated Bioremediation Research (NABIR) program, sponsored by the U.S. Department of Energy. It discusses why some efforts in science communication may succeed while others fail, provides methods of approaching group interactions about science that may better orient expert participants, and summarizes experience drawn from observations of groups interacting about topics in bioremediation or the NABIR program. The primer also provides brief, useful models for interacting with either expert or non-expert groups. Finally, it identifies topical areas that may help scientists prepare for public meetings, based on the developers' ongoing research in science communication in public forums.
Date: September 27, 2000
Creator: Bilyard, Gordon R.; Word, Charlotte J.; Weber, James R. & Harding, Anna K.
Partner: UNT Libraries Government Documents Department

Mobile X-ray imaging systems for the tank waste characterization project at the Hanford site

Description: Stored waste tank sampling of radioactive high-level nuclear waste is reilu ired for continued operations, waste characterization, and site safety. The Hanford site tank farms consist of 28 double- shell and 1.49 single-shell underground storage tanks. The ``full`` capacity of each of these tanks is approximately 1 million gallons. The waste stored in these tanks was generated as a result of defense materials production over the course of 4 decades. The single shell tanks are out-of-service and no longer receive liquid waste. Core samples of salt cake, liquid and sludge are remotely obtained using truck-mounted core drill platforms. Samples are recovered from the tanks through a 2.25-inch diameter drill pipe,, in segments contained in specially designed stainless steel samplers approximately 1.5-inch in outside diameter and 26-inches long. The sampled material in a given segment can include crystalline salt-cake, liquid, sludge and entrained gas. Drilling parameters will necessarily vary with different waste types, e.g., crystalline salt-cake versus sludge. At times, the core sample recovery has been marginal and inadequate for laboratory analysis needs. This necessitated a system to provide the drill-truck operators with ``real-time`` feedback about the physical condition of the sampled ``formation`` and the percent recovery, prior to receiving .,isual characterization information and nuclear assay measurements from the Hanford site 222-S Analytic!al laboratories, a process often requiring two week turn-around of data. This real- time information allows the drill-truck engineers to immediately vary the drilling parameters to maintain sample recovery.
Date: September 25, 1996
Creator: Weber, J.R.
Partner: UNT Libraries Government Documents Department

Copper in silicon: Quantitative analysis of internal and proximity gettering

Description: The behavior of copper in the presence of a proximity gettering mechanism and a standard internal gettering mechanism in silicon was studied. He implantation-induced cavities in the near surface region were used as a proximity gettering mechanism and oxygen precipitates in the bulk of the material provided internal gettering sites. Moderate levels of copper contamination were introduced by ion implantation such that the copper was not supersaturated during the anneals, thus providing realistic copper contamination/gettering conditions. Copper concentrations at cavities and internal gettering sites were quantitatively measured after the annealings. In this manner, the gettering effectiveness of cavities was measured when in direct competition with internal gettering sites. The cavities were found to be the dominant gettering mechanism with only a small amount of copper gettered at the internal gettering sites. These results reveal the benefits of a segregation-type gettering mechanism for typical contamination conditions.
Date: August 1, 1997
Creator: McHugo, S.A.; Flink, C. & Weber, E.R.
Partner: UNT Libraries Government Documents Department

Atomic scale interface structure of In{sub 0.2}Ga{sub 0.8}As/GaAs strained layers studied by cross-sectional scanning tunneling microscopy

Description: A molecular beam epitaxy-grown In{sub 0.2}Ga{sub 0.8}As/GaAs strained layer structure has been studied by scanning tunneling microscopy in cross-section on the (110) cleavage plane perpendicular to [001] the growth direction. Individual indium atoms were differentially imaged in the group III sublattice, allowing, a direct observation of the interface roughness due to the indium compositional fluctuation. In the In{sub 0.2}Ga{sub 0.8}As layers, Indium atoms are found in clusters preferentially along the growth direction with each cluster containing 2--3 indium atoms. Indium segregation induced asymmetrical interface broadening is studied on an atomic scale. The interface of In{sub 0.2}Ga{sub 0.8}As grown on GaAs is sharp within 2--4 atomic layers. The interface of GaAs grown on In{sub 0.2}Ga{sub 0.8}As is found to be broadened to about 5--10 atomic layers. The atomic scale fluctuation due to indium distribution is about 20 {angstrom} alone the interface in this case. The authors conclude that clustering and segregation are the main reason for the In{sub 0.2}Ga{sub 0.8}As/GaAs interface roughness.
Date: November 1, 1993
Creator: Zheng, J.F.; Weber, E.R. & Salmeron, M.B.
Partner: UNT Libraries Government Documents Department

Guidelines - A Primer for Communicating Effectively with NABIR Stakeholders

Description: This primer is a tool to help prepare scientists for meetings with stakeholders. It was prepared for staff involved with the Natural and Accelerated Bioremediation Research (NABIR) program, sponsored by the U.S. Department of Energy. It discusses why some efforts in science communication may succeed while others fail, provides methods of approaching group interactions about science that may better orient expert participants, and summarizes experience drawn from observations of groups interacting about topics in bioremediation or the NABIR program. The primer also provides brief, useful models for interacting with either expert or non-expert groups. Finally, it identifies topical areas that may help scientists prepare for public meetings, based on the developers' ongoing research in science communication in public forums.
Date: September 27, 2000
Creator: Bilyard, G.R.; Word, C.J.; Weber, J.R. & Harding, A.K.
Partner: UNT Libraries Government Documents Department

Competition between gettering by implantation-induced cavities in silicon and internal gettering associated with SiO{sub 2} precipitation

Description: Dissolved or metallic impurities can degrade silicon integrated circuit (IC) device yields when present in the near surface, active device region. This is such a critical issue that the IC community has set specifications for the reduction of metallic impurities down to 2.5 {times} 10{sup 9} atoms/cm{sup 3}. The exceptionally high diffusivity and solubility of Cu and Fe in silicon and their presence in many processing tools makes these impurities of particular interest. Additionally, Cu is being considered as an interconnect material because of its low electrical resistivity which creates a high potential for contamination. Here, the gettering behavior of Cu and Fe was investigated in CZ silicon which contained both internal-gettering sites in the bulk due to SiO{sub 2} precipitation and a device-side layer of cavities formed by He implantation and annealing. The objective was to quantify the effectiveness of impurity gettering at cavities relative to the widely used internal-gettering process. Both rapid thermal anneals and furnace anneals were used during the gettering sequences to reveal transient effects as well as the final, thermodynamically-equilibrated condition. For temperatures of 700, 800 and 850 C, the cavity gettering was observed to predominate over internal gettering as indicated both by the number of gettered atoms in the cavities and the residual solution concentration in the device region. The results are interpreted in detail by numerically solving the diffusion equation with sink-related source terms based on earlier, fundamental studies of the underlying mechanisms of internal and cavity gettering.
Date: December 31, 1996
Creator: McHugo, S.A.; Weber, E.R.; Myers, S.M. & Petersen, G.A.
Partner: UNT Libraries Government Documents Department

Scanning tunneling microscopy of Si donors in GaAs

Description: Using scanning tunneling microscopy, we have identified and characterized Si donors (Si{sub Ga}) in GaAs located on the (110) surface and in subsurface layers. Si{sub Ga} on the surface shows localized features with characteristic structures in good agreement with a recent theoretical calculation. Si{sub Ga} in subsurface layers appears as delocalized protrusions superimposed on the background lattice, which are interpreted in terms of the modification of the tunneling due to the tip-induced band bending perturbed by the Si{sub Ga} Coulomb potential.
Date: July 1, 1993
Creator: Zheng, J.F.; Weber, E.R.; Liu, X.; Newman, N.; Ogletree, D.F. & Salmeron, M.B.
Partner: UNT Libraries Government Documents Department

Organizational Identity, Health Identity, and Motivation: a Symbolic Interactionist Approach to the Understanding of Heath Behaviors in Work Settings

Description: Identity is an important determinant of behavior. This paper proposed an identity model as one way of understanding those factors related to the perceived probability or willingness of a worker to participate in health promotion programming at the worksite. Part of a larger study on employee wellness, this study took place in the municipal complex of a small city in the southeastern United States. A stratified cross sectional sample of 150 employees was selected utilizing a systematic random sampling methodology. Structured interviews were conducted with 129 participants resulting in a response rate of 92% after adjusting for those people no longer employed by the city. In order to test the identity model developed by this author, descriptive analysis, simple multiple regression analysis and path analysis were utilized. The dependent variable, perceived willingness to participate in health promotion programming, was examined in relationship to commitment to one's health identity, commitment to one's organizational identity, tendency to comply with health initiatives, and the forms of supervisory power utilized to enact employee compliance. The descriptive analysis revealed that subjective health status is moderately and positively associated with commitment to one's health identity, that individuals can be strongly committed to a negative/destructive health identity, and that both the family and physician play important roles as health advice givers. The path analysis revealed that commitment to one's organizational identity, commitment to one's health identity, and tendency to comply with health initiatives are significantly and positively associated with willingness to participate in health promotion programming, accounting for 25% of the variance in the dependent variable. In contrast, the forms of supervisory power were not shown to be related to the dependent variable. In conclusion, the identity model appears to be a useful tool for the understanding of health attitudes and behaviors within a work setting.
Date: May 1989
Creator: Weber, Linda R. (Linda Roberta)
Partner: UNT Libraries

Electrical and optical properties of carbon-doped GaN grown by MBE on MOCVD GaN templates using a CCl4 dopant source

Description: Carbon-doped GaN was grown by plasma-assisted molecular-beam epitaxy using carbon tetrachloride vapor as the dopant source. For moderate doping mainly acceptors were formed, yielding semi-insulating GaN. However at higher concentrations p-type conductivity was not observed, and heavily doped films (>5 x 10{sup 20} cm{sup -3}) were actually n-type rather than semi-insulating. Photoluminescence measurements showed two broad luminescence bands centered at 2.2 and 2.9 eV. The intensity of both bands increased with carbon content, but the 2.2 eV band dominated in n-type samples. Intense, narrow ({approx}6 meV) donor-bound exciton peaks were observed in the semi-insulating samples.
Date: April 15, 2002
Creator: Armitage, Rob; Yang, Qing; Feick, Henning; Park, Yeonjoon & Weber, Eicke R.
Partner: UNT Libraries Government Documents Department

Scrape-Off-Layer Flow Studies in Tokamaks: Final Report of LDRD Project 09-ERD-025

Description: A summary is given of the work carried out under the LDRD project 09-ERD-025 entitled Scrape-Off-Layer Flow Studies in Tokamaks. This project has lead to implementation of the new prototype Fourier Transform Spectrometer edge plasma flow diagnostic on the DIII-D National Fusion Facility at General Atomics, acquisition of carbon impurity concentration and flow data, and demonstration that the resulting data compare reasonably well with LLNL's edge plasma transport code UEDGE. Details of the work are contained in attached published papers, while the most recent results that are being written-up for publication are summarized in the report. Boundary plasma flows in tokamak fusion devices are key in determining the distribution of fuel and impurity ions, with tritium build-up in the walls an especially critical operational issue. The intrusion of impurity ions to the hot plasma core region can result in serious energy-loss owing to line radiation. However, flow diagnostic capability has been severely limited in fusion-relevant hot edge plasmas where Langmuir-type probes cannot withstand the high heat flux and traditional Doppler spectroscopy has limited resolution and signal strength. Thus, new edge plasma flow diagnostic capabilities need to be developed that can be used in existing and future devices such as ITER. The understanding of such flows requires simulation with 2-dimensional transport codes owing to the geometrical complexity of the edge region in contact with material surfaces and the large number of interaction physical processes including plasma flow along and across the magnetic field, and coupling between impurity and neutral species. The characteristics of edge plasma flows are substantially affected by cross-magnetic-field drifts (ExB/B{sup 2} and BxVB/B{sup 2}), which are known to introduce substantial convergence difficulty for some cases. It is important that these difficulties be overcome so that drifts can be included in transport models, both for validation with existing data ...
Date: November 21, 2011
Creator: Rognlien, T D; Allen, S L; Ellis, R M; Porter, G D; Nam, S K; Weber, T R et al.
Partner: UNT Libraries Government Documents Department

Interactions of structural defects with metallic impurities in multicrystalline silicon

Description: Interactions between structural defects and metallic impurities were studied in multicrystalline silicon for solar cells applications. The objective was to gain insight into the relationship between solar cell processing, metallic impurity behavior and the resultant effect on material/device performance. With an intense synchrotron x-ray source, high sensitivity x-ray fluorescence measurements were utilized to determine impurity distributions with a spatial resolution of {approx} 1{micro}m. Diffusion length mapping and final solar cell characteristics gauged material/device performance. The materials were tested in both the as-grown state and after full solar cell processing. Iron and nickel metal impurities were located at structural defects in as-grown material, while after solar cell processing, both impurities were still observed in low performance regions. These results indicate that multicrystalline silicon solar cell performance is directly related to metal impurities which are not completely removed during typical processing treatments. A discussion of possible mechanisms for this incomplete removal is presented.
Date: November 1996
Creator: McHugo, S.A.; Hieslmair, H.; Weber, E.R.; Rosenblum, M.D. & Kalejs, J.P.
Partner: UNT Libraries Government Documents Department