Realistic Probability Estimates For Destructive Overpressure Events In Heated Center Wing Tanks Of Commercial Jet Aircraft (open access)

Realistic Probability Estimates For Destructive Overpressure Events In Heated Center Wing Tanks Of Commercial Jet Aircraft

The Federal Aviation Administration (FAA) identified 17 accidents that may have resulted from fuel tank explosions on commercial aircraft from 1959 to 2001. Seven events involved JP 4 or JP 4/Jet A mixtures that are no longer used for commercial aircraft fuel. The remaining 10 events involved Jet A or Jet A1 fuels that are in current use by the commercial aircraft industry. Four fuel tank explosions occurred in center wing tanks (CWTs) where on-board appliances can potentially transfer heat to the tank. These tanks are designated as ''Heated Center Wing Tanks'' (HCWT). Since 1996, the FAA has significantly increased the rate at which it has mandated airworthiness directives (ADs) directed at elimination of ignition sources. This effort includes the adoption, in 2001, of Special Federal Aviation Regulation 88 of 14 CFR part 21 (SFAR 88 ''Fuel Tank System Fault Tolerance Evaluation Requirements''). This paper addresses SFAR 88 effectiveness in reducing HCWT ignition source probability. Our statistical analysis, relating the occurrence of both on-ground and in-flight HCWT explosions to the cumulative flight hours of commercial passenger aircraft containing HCWT's reveals that the best estimate of HCWT explosion rate is 1 explosion in 1.4 x 10{sup 8} flight hours. Based on …
Date: February 7, 2007
Creator: Alvares, N. & Lambert, H.
Object Type: Article
System: The UNT Digital Library
NK-1 Removable Cryogenic Shroud (A Study of the Bimba Pneumatic Cylinder) (open access)

NK-1 Removable Cryogenic Shroud (A Study of the Bimba Pneumatic Cylinder)

The Mark 1 Cryostat requires a cryogenic shroud that must be retracted immediately before firing the NIF laser. This paper evaluates a pneumatic cylinder that has been chosen to open and close the shroud. After a variety of motion control and vacuum compatibility experiments, we concluded that the Bimba feedback control cylinder may be used to retract the shroud with certain modifications to its control system and additional rod seals.
Date: February 7, 2003
Creator: Anderson, K & Stefanescu, D
Object Type: Report
System: The UNT Digital Library
Evolution of Ni3X Precipitation Kinetics, Morphology and Spatial Correlations in Binary Ni-X Alloys Aged Under Externally Applied Stress (open access)

Evolution of Ni3X Precipitation Kinetics, Morphology and Spatial Correlations in Binary Ni-X Alloys Aged Under Externally Applied Stress

Coarsening of Ni3Al, Ni3Ga, Ni3Ge and Ni3Si precipitates in aged binary single-crystal Ni-Al, Ni-Ga, Ni-Ge and Ni-Si alloys under applied compressive stress was measured experimentally over the temperature range 600 to 700 °C. Experiments were also performed on binary Ni-Al single crystals deformed in tension at 640 °C. The orientation of the crystals was [100] in all the experiments. Compared to the kinetics of coarsening in unstressed alloys, coarsening was slightly slower in specimens aged under compression and slightly faster in specimens aged in tension. The effect of applied stress on morphology and spatial correlation was also measured and found to be small. Ni3Al precipitates of a given size generally tended to become more non-equiaxed and their interfaces more planar, with increasing compressive stress. Ni3Ge precipitates behaved differently, becoming more spherical in specimens aged under compression. The effect of applied stress on kinetics is attributed to the influence of elastic deformation on diffusion. A model was developed that predicts slightly slower diffusion under compression and slightly faster diffusion in tension. The elastic constants of single crystals of Ni-Al, Ni-Si, Ni-Ga and Ni-Ge solid solutions were measured from room temperature to about 1100 K using resonant ultrasound spectroscopy.
Date: February 7, 2006
Creator: Ardell, Alan J.
Object Type: Report
System: The UNT Digital Library
Computational Biology: A Strategic Initiative LDRD (open access)

Computational Biology: A Strategic Initiative LDRD

The goal of this Strategic Initiative LDRD project was to establish at LLNL a new core capability in computational biology, combining laboratory strengths in high performance computing, molecular biology, and computational chemistry and physics. As described in this report, this project has been very successful in achieving this goal. This success is demonstrated by the large number of referred publications, invited talks, and follow-on research grants that have resulted from this project. Additionally, this project has helped build connections to internal and external collaborators and funding agencies that will be critical to the long-term vitality of LLNL programs in computational biology. Most importantly, this project has helped establish on-going research groups in the Biology and Biotechnology Research Program, the Physics and Applied Technology Directorate, and the Computation Directorate. These groups include three laboratory staff members originally hired as post-doctoral researchers for this strategic initiative.
Date: February 7, 2002
Creator: Barsky, D. & Colvin, M.
Object Type: Report
System: The UNT Digital Library
AGING SYSTEM DESIGN DEVELOPMENT STRATEGY (open access)

AGING SYSTEM DESIGN DEVELOPMENT STRATEGY

This plan provides an overview, work to date, and the path forward for the design development strategy of the Aging cask for aging commercial spent nuclear fuel (CSNF) at the Yucca Mountain Project (YMP) repository site. Waste for subsurface emplacement at the repository includes US Department of Energy (DOE) high-level radioactive waste (HLW), DOE SNF, commercial fuel in dual-purpose canisters (DPCs), uncanistered bare fuel, naval fuel, and other waste types. Table 1-1 lists the types of radioactive materials that may be aged at YMP, and those materials that will not be placed in an aging cask or module. This plan presents the strategy for design development of the Aging system. The Aging system will not handle naval fuel, DOE HLW, MCOs, or DOE SNF since those materials will be delivered to the repository in a state and sequence that allows them to be placed into waste packages for emplacement. Some CSNF from nuclear reactors, especially CSNF that is thermally too hot for emplacement underground, will need to be aged at the repository.
Date: February 7, 2005
Creator: Beesley, J.
Object Type: Report
System: The UNT Digital Library
Numerical simulation of a laboratory-scale turbulent V-flame (open access)

Numerical simulation of a laboratory-scale turbulent V-flame

We present a three-dimensional, time-dependent simulation of a laboratory-scale rod-stabilized premixed turbulent V-flame. The simulations are performed using an adaptive time-dependent low Mach number model with detailed chemical kinetics and a mixture model for differential species diffusion. The algorithm is based on a second-order projection formulation and does not require an explicit subgrid model for turbulence or turbulence chemistry interaction. Adaptive mesh refinement is used to dynamically resolve the flame and turbulent structures. Here, we briefly discuss the numerical procedure and present detailed comparisons with experimental measurements showing that the computation is able to accurately capture the basic flame morphology and associated mean velocity field. Finally, we discuss key issues that arise in performing these types of simulations and the implications of these issues for using computation to form a bridge between turbulent flame experiments and basic combustion chemistry.
Date: February 7, 2005
Creator: Bell, J. B.; Day, M. S.; Shepherd, I. G.; Johnson, M.; Cheng, R. K.; Grcar, J. F. et al.
Object Type: Article
System: The UNT Digital Library
Demand Activated Manufacturing Architecture (open access)

Demand Activated Manufacturing Architecture

Honeywell Federal Manufacturing & Technologies (FM&T) engineers John Zimmerman and Tom Bender directed separate projects within this CRADA. This Project Accomplishments Summary contains their reports independently. Zimmerman: In 1998 Honeywell FM&T partnered with the Demand Activated Manufacturing Architecture (DAMA) Cooperative Business Management Program to pilot the Supply Chain Integration Planning Prototype (SCIP). At the time, FM&T was developing an enterprise-wide supply chain management prototype called the Integrated Programmatic Scheduling System (IPSS) to improve the DOE's Nuclear Weapons Complex (NWC) supply chain. In the CRADA partnership, FM&T provided the IPSS technical and business infrastructure as a test bed for SCIP technology, and this would provide FM&T the opportunity to evaluate SCIP as the central schedule engine and decision support tool for IPSS. FM&T agreed to do the bulk of the work for piloting SCIP. In support of that aim, DAMA needed specific DOE Defense Programs opportunities to prove the value of its supply chain architecture and tools. In this partnership, FM&T teamed with Sandia National Labs (SNL), Division 6534, the other DAMA partner and developer of SCIP. FM&T tested SCIP in 1998 and 1999. Testing ended in 1999 when DAMA CRADA funding for FM&T ceased. Before entering the partnership, FM&T discovered …
Date: February 7, 2001
Creator: Bender, T.R. & Zimmerman, J.J.
Object Type: Report
System: The UNT Digital Library
The Role of the Engineered Barrier System in Safety Cases for Geological Radioactive Waste Repoitories: An NEA Initiaive in Co-Operations with the EC, Process Issues and Modeling (open access)

The Role of the Engineered Barrier System in Safety Cases for Geological Radioactive Waste Repoitories: An NEA Initiaive in Co-Operations with the EC, Process Issues and Modeling

The Integration Group for the Safety Case (IGSC) of the Nuclear Energy Agency (NEA) Radioactive Waste Management Committee in co-operation with the European Commission (EC) is conducting a project to develop a greater understanding of how to achieve the necessary integration for successful design, construction, testing, modeling, and assessment of engineered barrier systems. The project also seeks to clarify the role that the EBS plays in assuring the overall safety of a repository. A framework for the EBS Project is provided by a series of workshops that allow discussion of the wide range of activities necessary for the design, assessment and optimization of the EBS, and the integration of this information into the safety case. The topics of this series of workshops have been planned so that the EBS project will work progressively through the main aspects comprising one cycle of the design and optimization process. This paper seeks to communicate key results from the EBS project to a wider audience. The paper focuses on two topics discussed at the workshops: process issues and the role of modeling.
Date: February 7, 2006
Creator: Bennett, David G.; Hooper, Alan J.; Voinis, Sylvie; Umeki, Hiroyuki; van Luik, Abe & Alonso, Jesus
Object Type: Report
System: The UNT Digital Library
Simulating Fine-Scale Atmospheric Processes: A New Core Capability and its Application to Predicting Wildfire Behavior (open access)

Simulating Fine-Scale Atmospheric Processes: A New Core Capability and its Application to Predicting Wildfire Behavior

This LDRD project consisted of the development, testing, and prototype application of a new capability to couple atmospheric models of different spatial and temporal scales with a state-of-the-science vegetation-fuel combustion model and a GIs-based analysis system. The research addressed the complex, multi-scale interactions of atmospheric processes, combustion, and vegetative fuel conditions, using a suite of models to simulate their impact on wildfire behavior in areas of complex terrain. During the course of the project, we made substantial progress toward the implementation of a world-class modeling system that could be used as a tool for wildfire risk assessment, wildfire consequence analysis, wildfire suppression planning, fuels management, firefighter training, and public fire-safety education. With one additional year of funding we would have been able conduct combined modeling and field experiments to evaluate the models capability to predict the behavior of prescribed burns before they are ignited. Because of its investment in this LDRD project, LLNL is very close to having a new core capability--likely the world's most generally applicable, most scientifically sound, and most respected wildfire simulation system.
Date: February 7, 2003
Creator: Bradley, M M; Leach, M J; Molenkamp, C R; Hall, C H; Wilder, L & Neher, L A
Object Type: Report
System: The UNT Digital Library
Final Report for LDRD Project on Rapid Problem Setup for Mesh-Based Simulation (Rapsodi) (open access)

Final Report for LDRD Project on Rapid Problem Setup for Mesh-Based Simulation (Rapsodi)

Under LLNL Exploratory Research LDRD funding, the Rapsodi project developed rapid setup technology for computational physics and engineering problems that require computational representations of complex geometry. Many simulation projects at LLNL involve the solution of partial differential equations in complex 3-D geometries. A significant bottleneck in carrying out these simulations arises in converting some specification of a geometry, such as a computer-aided design (CAD) drawing to a computationally appropriate 3-D mesh that can be used for simulation and analysis. Even using state-of-the-art mesh generation software, this problem setup step typically has required weeks or months, which is often much longer than required to carry out the computational simulation itself. The Rapsodi project built computational tools and designed algorithms that help to significantly reduce this setup time to less than a day for many realistic problems. The project targeted rapid setup technology for computational physics and engineering problems that use mixed-element unstructured meshes, overset meshes or Cartesian-embedded boundary (EB) meshes to represent complex geometry. It also built tools that aid in constructing computational representations of geometry for problems that do not require a mesh. While completely automatic mesh generation is extremely difficult, the amount of manual labor required can be significantly …
Date: February 7, 2003
Creator: Brown, D L; Henshaw, W; Petersson, N A; Fast, P & Chand, K
Object Type: Report
System: The UNT Digital Library
Geographical Distribution of Biomass Carbon in Tropical Southeast Asian Forests: A Database (open access)

Geographical Distribution of Biomass Carbon in Tropical Southeast Asian Forests: A Database

A database was generated of estimates of geographically referenced carbon densities of forest vegetation in tropical Southeast Asia for 1980. A geographic information system (GIS) was used to incorporate spatial databases of climatic, edaphic, and geomorphological indices and vegetation to estimate potential (i.e., in the absence of human intervention and natural disturbance) carbon densities of forests. The resulting map was then modified to estimate actual 1980 carbon density as a function of population density and climatic zone. The database covers the following 13 countries: Bangladesh, Brunei, Cambodia (Campuchea), India, Indonesia, Laos, Malaysia, Myanmar (Burma), Nepal, the Philippines, Sri Lanka, Thailand, and Vietnam. The data sets within this database are provided in three file formats: ARC/INFO{trademark} exported integer grids, ASCII (American Standard Code for Information Interchange) files formatted for raster-based GIS software packages, and generic ASCII files with x, y coordinates for use with non-GIS software packages. This database includes ten ARC/INFO exported integer grid files (five with the pixel size 3.75 km x 3.75 km and five with the pixel size 0.25 degree longitude x 0.25 degree latitude) and 27 ASCII files. The first ASCII file contains the documentation associated with this database. Twenty-four of the ASCII files were generated …
Date: February 7, 2002
Creator: Brown, S.
Object Type: Report
System: The UNT Digital Library
Lignite Fuel Enhancement Progress Report (open access)

Lignite Fuel Enhancement Progress Report

The Design Team continued to conference this quarter. Their primary task during this timeframe was to finalize the dryer design based on information learned from the NDIC Pilot work and detailed design discussions at Barr offices in August. Heyl-Patterson was tasked with incorporating all comments and drafting drawings. They submitted a preliminary proposal which spawned detailed discussions about tube bundle, air locks, and fire suppression systems. The type of fire protection specified dictated the final structural arrangement. Three meetings were spent discussing the pro's and con's of suppression vs. ventilation systems. In the end, the dryer and bucket elevator will have suppression systems and the remaining equipment will be explosion vented. This is in agreement with GRE's current insurer, FM Global. Three inlet airlocks were reduced to two and four outlets were reduced to three. The inlet plenum was subdivided for greater flexibility and sparging air added in the outlet plenum. It was also decided to use bundles with varied material, diameter, and tube & fin spacing. This will be completed in an effort to identify for us which configuration has the best heat transfer characteristics using coal as the fluidizing medium. The dryer will also be delivered in four …
Date: February 7, 2005
Creator: Bullinger, Charles
Object Type: Report
System: The UNT Digital Library
Novel Application of Fiber Optic Sensor for Characterizing Real-Time Contaminant Transport in Rapid Storm Runoff (open access)

Novel Application of Fiber Optic Sensor for Characterizing Real-Time Contaminant Transport in Rapid Storm Runoff

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Date: February 7, 2003
Creator: Campbell, C G; Richards, J; Zavarin, M; Stratton, P; Coty, J & Laycak, D
Object Type: Report
System: The UNT Digital Library
Characterization of the effect of short pulse exposure on laser damage size, morphology, and conditioning in wide band gap materials (open access)

Characterization of the effect of short pulse exposure on laser damage size, morphology, and conditioning in wide band gap materials

The first objective of this proposal was to develop a fundamental understanding of how short-pulse (100 ps to 1 ns) laser parameters affect conditioning and damage initiation in KDP and DKDP crystals. In this study we experimentally determine the effect of short-pulse laser parameters including pulse duration, pulse shape, and fluence on conditioning effectiveness, pinpoint damage density, pinpoint size, and pinpoint morphology in crystals. Based on the experimental results we developed empirical models, which give insight into the underlying physics of energy deposition from short-pulse lasers in KDP and DKDP crystals. The second objective of this proposal was to explore the mechanisms by which energy is deposited during damage in SiO{sub 2}. We have measured how laser parameters such as pulse duration, pulse shape, wavelength, and fluence are relevant to energy deposition, for initiation and growth on the surface of SiO{sub 2} optics.
Date: February 7, 2008
Creator: Carr, C. W.
Object Type: Report
System: The UNT Digital Library
Quantitative Methods for Reservoir Characterization and Improved Recovery: Application to Heavy Oil Sands (open access)

Quantitative Methods for Reservoir Characterization and Improved Recovery: Application to Heavy Oil Sands

Improved prediction of interwell reservoir heterogeneity was needed to increase productivity and to reduce recovery cost for California's heavy oil sands, which contain approximately 2.3 billion barrels of remaining reserves in the Temblor Formation and in other formations of the San Joaquin Valley. This investigation involved application of advanced analytical property-distribution methods conditioned to continuous outcrop control for improved reservoir characterization and simulation.
Date: February 7, 2003
Creator: Castle, J.W.; Molz, F.J.; Brame, S.E. & Falta, R.W.
Object Type: Report
System: The UNT Digital Library
Quantitative Methods for Reservoir Characterization and Improved Recovery: Application to Heavy Oil Sands (open access)

Quantitative Methods for Reservoir Characterization and Improved Recovery: Application to Heavy Oil Sands

Improved prediction of interwell reservoir heterogeneity is needed to increase productivity and to reduce recovery cost for California's heavy oil sands, which contain approximately 2.3 billion barrels of remaining reserves in the Temblor Formation and in other formations of the San Joaquin Valley. This investigation involved application of advanced analytical property-distribution methods conditioned to continuous outcrop control for improved reservoir characterization and simulation.
Date: February 7, 2003
Creator: Castle, James W. & Molz, Fred J.
Object Type: Report
System: The UNT Digital Library
Quantitative Methods for Reservoir Characterization and Improved Recovery: Application to Heavy Oil Sands (open access)

Quantitative Methods for Reservoir Characterization and Improved Recovery: Application to Heavy Oil Sands

Improved prediction of interwell reservoir heterogeneity was needed to increase productivity and to reduce recovery cost for California's heavy oil sands, which contain approximately 2.3 billion barrels of remaining reserves in the Temblor Formation and in other formations of the San Joaquin Valley. This investigation involved application of advanced analytical property-distribution methods conditioned to continuous outcrop control for improved reservoir characterization and simulation.
Date: February 7, 2003
Creator: Castle, James W.; Bridges, R. A.; Lorinovich, C. J.; Molz, Fred J.; Dinwiddie, C. L. & Lu, S.
Object Type: Report
System: The UNT Digital Library
Quantitative Methods for Reservoir Characterization and Improved Recovery: Application to Heavy Oil Sands (open access)

Quantitative Methods for Reservoir Characterization and Improved Recovery: Application to Heavy Oil Sands

Improved prediction of interwell reservoir heterogeneity was needed to increase productivity and to reduce recovery cost for California's heavy oil sands, which contain approximately 2.3 billion barrels of remaining reserves in the Temblor Formation and in other formations of the San Joaquin Valley. This investigation involved application of advanced analytical property-distribution methods conditioned to continuous outcrop control for improved reservoir characterization and simulation.
Date: February 7, 2003
Creator: Castle, James W.; Molz, Fred J.; Brame, Scott & Current, Caitlin J.
Object Type: Report
System: The UNT Digital Library
Quantitative Methods for Reservoir Characterization and Improved Recovery: Application to Heavy Oil Sands (open access)

Quantitative Methods for Reservoir Characterization and Improved Recovery: Application to Heavy Oil Sands

This project involved application of advanced analytical property-distribution methods conditioned to continuous outcrop control for improved reservoir characterization and simulation. The investigation was performed in collaboration with Chevron Production Company U.S.A. as an industrial partner, and incorporates data from the Temblor Formation in Chevron's West Coalinga Field, California. Improved prediction of interwell reservoir heterogeneity was needed to increase productivity and to reduce recovery cost for California's heavy oil sands, which contained approximately 2.3 billion barrels of remaining reserves in the Temblor Formation and in other formations of the San Joaquin Valley.
Date: February 7, 2003
Creator: Castle, James W.; Molz, Fred W.; Bridges, Robert A.; Dinwiddie, Cynthia L.; Lorinovich, Caitlin J. & Lu, Silong
Object Type: Report
System: The UNT Digital Library
Experimental study of variations in background radiation and the effect on Nuclear Car Wash sensitivity (open access)

Experimental study of variations in background radiation and the effect on Nuclear Car Wash sensitivity

Error rates in a cargo screening system such as the Nuclear Car Wash [1-7] depend on the standard deviation of the background radiation count rate. Because the Nuclear Car Wash is an active interrogation technique, the radiation signal for fissile material must be detected above a background count rate consisting of cosmic, ambient, and neutron-activated radiations. It was suggested previously [1,6] that the Corresponding negative repercussions for the sensitivity of the system were shown. Therefore, to assure the most accurate estimation of the variation, experiments have been performed to quantify components of the actual variance in the background count rate, including variations in generator power, irradiation time, and container contents. The background variance is determined by these experiments to be a factor of 2 smaller than values assumed in previous analyses, resulting in substantially improved projections of system performance for the Nuclear Car Wash.
Date: February 7, 2007
Creator: Church, J; Slaughter, D; Norman, E; Asztalos, S & Biltoft, P
Object Type: Report
System: The UNT Digital Library
Scoping Studies to Develop a Method to Determine Particle Size in Simulant Sludge Slurries by Sieving (open access)

Scoping Studies to Develop a Method to Determine Particle Size in Simulant Sludge Slurries by Sieving

A physical separation method (i.e. sieving) was investigated to determine particle size distribution in non-radioactive sludge slurry simulants with the goal of implementation into the SRNL (Savannah River National Laboratory) shielded cells for use with radioactive sludge slurries. The investigation included obtaining the necessary experimental equipment, developing accessory equipment for use with the sieve shaker (to be able to sieve simulant slurries with aqueous solutions), sieving three different simulant slurries through a number of sieves and determining the particle size distribution gravimetrically, and developing a sufficient cleaning protocol of the sieves for re-use. The experimental protocol involved successive sieving of a NIST standard (to check the particle size retention of the sieves) and three non-radioactive slurry simulants (Batch 3 Tank 40 Test 3, Tank 40 Drum 3 and CETL Sludge Batch 2, which had been previously characterized by Microtrac analysis) through smaller and smaller sieves (150 microns x 5 microns) via use of the wet sieving system or by hand. For each of the three slurries, duplicate experiments were carried out using filtered supernate and DI water (to check the accuracy of the method versus Microtrac data) to sieve the slurry. Particle size determinations using the wet sieving system with …
Date: February 7, 2005
Creator: Click, D. R.
Object Type: Report
System: The UNT Digital Library
LDRD ER Final Report: Recreating Planetary Cores in the Laboratory: New Techniques to Extremely High Density States (open access)

LDRD ER Final Report: Recreating Planetary Cores in the Laboratory: New Techniques to Extremely High Density States

An accurate equation of state (EOS) for planetary constituents at extreme conditions is the key to any credible model of planets or low mass stars. However, very few materials have their high pressure (>few Mbar) EOS experimentally validated, and even then, only on the principal Hugoniot. For planetary and stellar interiors, compression occurs from gravitational force so that material states follow a line of isotropic compression (ignoring phase separation) to ultra-high densities. An example of the hydrogen phase space composing Jupiter and one particular Brown Dwarf is shown. At extreme densities, material states are predicted to have quite unearthly properties such as high temperature superconductivity and low temperature fusion. High density experiments on Earth are achieved with either static compression techniques (i.e. diamond anvil cells) or dynamic compression techniques using large laser facilities, gas guns, or explosives. The ultimate goal of this multi-directorate and multi-institutional proposal was to develop techniques that will enable us to understand material states that previously only existed at the core of giant planets, stars, or speculative theories. Our effort was a complete success, meeting all of the objectives set out in our proposals. First we focused on developing accurate Hugoniot techniques to be used for …
Date: February 7, 2003
Creator: Collins, G.; Celliers, P.; Hicks, D.; Cauble, R.; Bradley, D.; MacKinnon, A. et al.
Object Type: Report
System: The UNT Digital Library
New Approaches to Quantum Computing Using Nuclear Magnetic Resonance Spectroscopy (open access)

New Approaches to Quantum Computing Using Nuclear Magnetic Resonance Spectroscopy

The power of a quantum computer (QC) relies on the fundamental concept of the superposition in quantum mechanics and thus allowing an inherent large-scale parallelization of computation. In a QC, binary information embodied in a quantum system, such as spin degrees of freedom of a spin-1/2 particle forms the qubits (quantum mechanical bits), over which appropriate logical gates perform the computation. In classical computers, the basic unit of information is the bit, which can take a value of either 0 or 1. Bits are connected together by logic gates to form logic circuits to implement complex logical operations. The expansion of modern computers has been driven by the developments of faster, smaller and cheaper logic gates. As the size of the logic gates become smaller toward the level of atomic dimensions, the performance of such a system is no longer considered classical but is rather governed by quantum mechanics. Quantum computers offer the potentially superior prospect of solving computational problems that are intractable to classical computers such as efficient database searches and cryptography. A variety of algorithms have been developed recently, most notably Shor's algorithm for factorizing long numbers into prime factors in polynomial time and Grover's quantum search algorithm. …
Date: February 7, 2003
Creator: Colvin, M. & Krishnan, V. V.
Object Type: Report
System: The UNT Digital Library
DEVELOPMENT OF BYPASSED OIL RESERVES USING BEHIND CASING RESISTIVITY MEASUREMENTS (open access)

DEVELOPMENT OF BYPASSED OIL RESERVES USING BEHIND CASING RESISTIVITY MEASUREMENTS

Tubing and rods of the S.P. Pedro-Nepple No.1 well were pulled and the well was prepared for running of Schlumberger's Cased Hole Formation Resistivity Tool (CHFR) in selected intervals. The CHFR tool was successfully run and data was captured. The CHFR formation resistivity readings were compared to original open hole resistivity measurements. Separation between the original and CHFR resistivity curves indicate both swept and un-swept sand intervals. Both watered out sand intervals and those with higher remaining oil saturation have been identified. Due to the nature of these turbidite sands being stratigraphically continuous, both the swept and unswept layers have been correlated across to one of the four nearby offset shallow wells. As a result of the cased hole logging, one well was selected for a workover to recomplete high oil saturated shallow sand intervals. During the second report period, well S.P. Pedro-Nepple No.2 was plugged back with cement excluding the previously existing production interval, squeeze cemented behind casing, selectively perforated in the shallower ''Bell'' zone and placed on production to develop potential new oil reserves and increase overall well productivity. Prior workover production averaged 3.0 BOPD for the previous six-months. Post workover well production was marginally increased to 3.7 …
Date: February 7, 2005
Creator: Conner, Michael G. & Blesener, Jeffrey A.
Object Type: Report
System: The UNT Digital Library