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Some attributes of a language for property-based testing. (open access)

Some attributes of a language for property-based testing.

Property-based testing is a testing technique that evaluates executions of a program. The method checks that specifications, called properties, hold throughout the execution of the program. TASpec is a language used to specify these properties. This paper compares some attributes of the language with the specification patterns used for model-checking languages, and then presents some descriptions of properties that can be used to detect common security flaws in programs. This report describes the results of a one year research project at the University of California, Davis, which was funded by a University Collaboration LDRD entitled ''Property-based Testing for Cyber Security Assurance''.
Date: November 1, 2004
Creator: Neagoe, Vicentiu (University of California, Davis, CA) & Bishop, Matt (University of California, Davis, CA)
Object Type: Report
System: The UNT Digital Library
Temperature rise of the mask-resist assembly during LIGA exposure. (open access)

Temperature rise of the mask-resist assembly during LIGA exposure.

Deep X-ray lithography on PMMA resist is used in the LIGA process. The resist is exposed to synchrotron X-rays through a patterned mask and then is developed in a liquid developer to make high aspect ratio microstructures. The limitations in dimensional accuracies of the LIGA generated microstructure originate from many sources, including synchrotron and X-ray physics, thermal and mechanical properties of mask and resist, and from the kinetics of the developer. This work addresses the thermal analysis and temperature rise of the mask-resist assembly during exposure in air at the Advanced Light Source (ALS) synchrotron. The concern is that dimensional errors generated at the mask and the resist due to thermal expansion will lower the accuracy of the lithography. We have developed a three-dimensional finite-element model of the mask and resist assembly that includes a mask with absorber, a resist with substrate, three metal holders, and a water-cooling block. We employed the LIGA exposure-development software LEX-D to calculate volumetric heat sources generated in the assembly by X-ray absorption and the commercial software ABAQUS to calculate heat transfer including thermal conduction inside the assembly, natural and forced convection, and thermal radiation. at assembly outer and/or inner surfaces. The calculations of assembly …
Date: November 1, 2004
Creator: Ting, Aili
Object Type: Report
System: The UNT Digital Library
Alignment of the MINOS FD (open access)

Alignment of the MINOS FD

The results and procedure of the alignment of the MINOS Far Detector are presented. The far detector has independent alignments of SM1 and SM2. The misalignments have an estimated uncertainty of {approx}850 {micro}m for SM1 and {approx}750 {micro}m for SM2. The alignment has as inputs the average rotations of U and V as determined by optical survey and strip positions within modules measured from the module mapper. The output of this is a module-module correction for transverse mis-alignments. These results were verified by examining an independent set of data. These alignment constants on average contribute much less then 1% to the total uncertainty in the transverse strip position.
Date: November 1, 2004
Creator: Becker, B. & Boehnlein, D.
Object Type: Report
System: The UNT Digital Library
Matrixed business support comparison study. (open access)

Matrixed business support comparison study.

The Matrixed Business Support Comparison Study reviewed the current matrixed Chief Financial Officer (CFO) division staff models at Sandia National Laboratories. There were two primary drivers of this analysis: (1) the increasing number of financial staff matrixed to mission customers and (2) the desire to further understand the matrix process and the opportunities and challenges it creates.
Date: November 1, 2004
Creator: Parsons, Josh D.
Object Type: Report
System: The UNT Digital Library
Red River Wildlife Management Area HEP Report, Habitat Evaluation Procedures, Technical Report 2004. (open access)

Red River Wildlife Management Area HEP Report, Habitat Evaluation Procedures, Technical Report 2004.

A habitat evaluation procedures (HEP) analysis conducted on the 314-acre Red River Wildlife Management Area (RRWMA) managed by the Idaho Department of Fish and Game resulted in 401.38 habitat units (HUs). Habitat variables from six habitat suitability index (HSI) models, comprised of mink (Mustela vison), mallard (Anas platyrhynchos), common snipe (Capella gallinago), black-capped chickadee (Parus altricapillus), yellow warbler (Dendroica petechia), and white-tailed deer (Odocoileus virginianus), were measured by Regional HEP Team (RHT) members in August 2004. Cover types included wet meadow, riverine, riparian shrub, conifer forest, conifer forest wetland, and urban. HSI model outputs indicate that the shrub component is lacking in riparian shrub and conifer forest cover types and that snag density should be increased in conifer stands. The quality of wet meadow habitat, comprised primarily of introduced grass species and sedges, could be improved through development of ephemeral open water ponds and increasing the amount of persistent wetland herbaceous vegetation e.g. cattails (Typha spp.) and bulrushes (Scirpus spp.).
Date: November 1, 2004
Creator: Ashley, Paul
Object Type: Report
System: The UNT Digital Library
LDRD final report on new homogeneous and supported oligomerization catalysts (LDRD 42461). (open access)

LDRD final report on new homogeneous and supported oligomerization catalysts (LDRD 42461).

The overall purpose of this LDRD is multifold. First, we are interested in preparing new homogeneous catalysts that can be used in the oligomerization of ethylene and in understanding commercially important systems better. Second, we are interested in attempting to support these new homogeneous catalysts in the pores of nano- or mesoporous materials in order to force new and unusual distributions of a-olefins to be formed during the oligomerization. Thus the overall purpose is to try to prepare new catalytic species and to possibly control the active site architecture in order to yield certain desired products during a catalytic reaction, much like nature does with enzymes. In order to rationally synthesize catalysts it is imperative to comprehend the function of the various components of the catalyst. In heterogeneous systems, it is of utmost importance to know how a support interacts with the active site of the catalyst. In fact, in the catalysis world this lack of fundamental understanding of the relationship between active site and support is the single largest reason catalysis is considered an 'empirical' or 'black box' science rather than a well-understood one. In this work we will be preparing novel ethylene oligomerization catalysts, which are normally P-O …
Date: November 1, 2004
Creator: Hascall, Anthony G. & Kemp, Richard Alan
Object Type: Report
System: The UNT Digital Library
Self-assembled ordered carbon-nanotube arrays and membranes. (open access)

Self-assembled ordered carbon-nanotube arrays and membranes.

Imagine free-standing flexible membranes with highly-aligned arrays of carbon nanotubes (CNTs) running through their thickness. Perhaps with both ends of the CNTs open for highly controlled nanofiltration? Or CNTs at heights uniformly above a polymer membrane for a flexible array of nanoelectrodes or field-emitters? How about CNT films with incredible amounts of accessible surface area for analyte adsorption? These self-assembled crystalline nanotubes consist of multiple layers of graphene sheets rolled into concentric cylinders. Tube diameters (3-300 nm), inner-bore diameters (2-15 nm), and lengths (nanometers - microns) are controlled to tailor physical, mechanical, and chemical properties. We proposed to explore growth and characterize nanotube arrays to help determine their exciting functionality for Sandia applications. Thermal chemical vapor deposition growth in a furnace nucleates from a metal catalyst. Ordered arrays grow using templates from self-assembled hexagonal arrays of nanopores in anodized-aluminum oxide. Polymeric-binders can mechanically hold the CNTs in place for polishing, lift-off, and membrane formation. The stiffness, electrical and thermal conductivities of CNTs make them ideally suited for a wide-variety of possible applications. Large-area, highly-accessible gas-adsorbing carbon surfaces, superb cold-cathode field-emission, and unique nanoscale geometries can lead to advanced microsensors using analyte adsorption, arrays of functionalized nanoelectrodes for enhanced electrochemical detection …
Date: November 1, 2004
Creator: Overmyer, Donald L.; Siegal, Michael P. & Yelton, William Graham
Object Type: Report
System: The UNT Digital Library
Nanoporous-carbon adsorbers for chemical microsensors. (open access)

Nanoporous-carbon adsorbers for chemical microsensors.

Chemical microsensors rely on partitioning of airborne chemicals into films to collect and measure trace quantities of hazardous vapors. Polymer sensor coatings used today are typically slow to respond and difficult to apply reproducibly. The objective of this project was to produce a durable sensor coating material based on graphitic nanoporous-carbon (NPC), a new material first studied at Sandia, for collection and detection of volatile organic compounds (VOC), toxic industrial chemicals (TIC), chemical warfare agents (CWA) and nuclear processing precursors (NPP). Preliminary studies using NPC films on exploratory surface-acoustic-wave (SAW) devices and as a {micro}ChemLab membrane preconcentrator suggested that NPC may outperform existing, irreproducible coatings for SAW sensor and {micro}ChemLab preconcentrator applications. Success of this project will provide a strategic advantage to the development of a robust, manufacturable, highly-sensitive chemical microsensor for public health, industrial, and national security needs. We use pulsed-laser deposition to grow NPC films at room-temperature with negligible residual stress, and hence, can be deposited onto nearly any substrate material to any thickness. Controlled deposition yields reproducible NPC density, morphology, and porosity, without any discernable variation in surface chemistry. NPC coatings > 20 {micro}m thick with density < 5% that of graphite have been demonstrated. NPC can …
Date: November 1, 2004
Creator: Overmyer, Donald L.; Siegal, Michael P.; Staton, Alan W.; Provencio, Paula Polyak & Yelton, William Graham
Object Type: Report
System: The UNT Digital Library
Human error mitigation initiative (HEMI) : summary report. (open access)

Human error mitigation initiative (HEMI) : summary report.

Despite continuing efforts to apply existing hazard analysis methods and comply with requirements, human errors persist across the nuclear weapons complex. Due to a number of factors, current retroactive and proactive methods to understand and minimize human error are highly subjective, inconsistent in numerous dimensions, and are cumbersome to characterize as thorough. An alternative and proposed method begins with leveraging historical data to understand what the systemic issues are and where resources need to be brought to bear proactively to minimize the risk of future occurrences. An illustrative analysis was performed using existing incident databases specific to Pantex weapons operations indicating systemic issues associated with operating procedures that undergo notably less development rigor relative to other task elements such as tooling and process flow. Future recommended steps to improve the objectivity, consistency, and thoroughness of hazard analysis and mitigation were delineated.
Date: November 1, 2004
Creator: Stevens, Susan M.; Ramos, M. Victoria; Wenner, Caren A. & Brannon, Nathan Gregory
Object Type: Report
System: The UNT Digital Library
Laboratory evaluation of damage criteria and permeability of Big Hill salt. (open access)

Laboratory evaluation of damage criteria and permeability of Big Hill salt.

To establish strength criteria of Big Hill salt, a series of quasi-static triaxial compression tests have been completed. This report summarizes the test methods, set-up, relevant observations, and results. The triaxial compression tests established dilatant damage criteria for Big Hill salt in terms of stress invariants (I{sub 1} and J{sub 2}) and principal stresses ({sigma}{sub a,d} and {sigma}{sub 3}), respectively: {radical}J{sub 2}(psi) = 1746-1320.5 exp{sup -0.00034I{sub 1}(psi)}; {sigma}{sub a,d}(psi) = 2248 + 1.25 {sigma}{sub 3} (psi). For the confining pressure of 1,000 psi, the dilatant damage strength of Big Hill salt is identical to the typical salt strength ({radical}J{sub 2} = 0.27 I{sub 1}). However, for higher confining pressure, the typical strength criterion overestimates the damage strength of Big Hill salt.
Date: November 1, 2004
Creator: Ehgartner, Brian L.; Park, Byoung Yoon; Lee, Moo Yul & Bronowski, David R.
Object Type: Report
System: The UNT Digital Library
Equation of state and electrical conductivity of stainless steel. (open access)

Equation of state and electrical conductivity of stainless steel.

Warm dense matter is the region in phase space of density and temperature where the thermal, Fermi, and Coulomb energies are approximately equal. The lack of a dominating scale and physical behavior makes it challenging to model the physics to high fidelity. For Sandia, a fundamental understanding of the region is of importance because of the needs of our experimental HEDP programs for high fidelity descriptive and predictive modeling. We show that multi-scale simulations of macroscopic physical phenomena now have predictive capability also for difficult but ubiquitous materials such as stainless steel, a transition metal alloy.
Date: November 1, 2004
Creator: Desjarlais, Michael Paul & Mattsson, Thomas Kjell Rene
Object Type: Report
System: The UNT Digital Library
Growth and property development of convection pass deposits in recovery boilers : final project project. (open access)

Growth and property development of convection pass deposits in recovery boilers : final project project.

As part of the U.S. Department of Energy (DOE) Office of Industrial Technologies (OIT) Industries of the Future (IOF) Forest Products research program, the mechanisms of particle deposition and properties of deposits that form in the convection passes of recovery boilers were investigated. Research from experimental facilities at Sandia National Laboratories, the Institute of Paper Science and Technology (IPST), and the University of Toronto (U of T) was coordinated into a single effort to define the controlling mechanisms and rates of deposition. Deposition rates were recorded on a volumetric and mass basis in a Sandia facility for particle sizes in the range of 0.1 to 150 {micro}m. Deposit thickness, mass, spectral emissivity, thermal conductivity, surface temperature, and apparent density were monitored simultaneously and in situ on instrumented probes that allow determination of heat flux and probe surface temperature. Particle composition and mass deposition rates were also recorded in a U of T facility for particle sizes in the range of 100 to 600 {micro}m. These measurements allowed determination of the liquid content and sticking efficiency of carryover particles that inertially impact on a deposition probe. In addition, information on particulates, stable gas species, gas temperature and velocity were obtained from …
Date: November 1, 2004
Creator: Lien, Steve J. (Georgia Institute of Technology, Atlanta, GA); Baxter, Larry L.; Frederick, W. James Jr. (Georgia Institute of Technology, Atlanta, GA) & Wessel, Richard A. (Babcock & Wilcox Company, Barberton, OH)
Object Type: Report
System: The UNT Digital Library
Permeability Modification Using a Reactive Alkaline-Soluble Biopolymer (open access)

Permeability Modification Using a Reactive Alkaline-Soluble Biopolymer

Polymer injection has been used in reservoirs to alleviate contrasting permeability zones to enhance oil recovery (EOR). Polymer technology relies mainly on the use of polyacrylamides cross-linked by a hazardous metal or organic. Contemporary polymer plugging has investigated the stimulation of in-situ microorganisms to produce polymers (Jenneman et. al., 2000) and the use of biocatalysts to trigger gelling (Bailey et. al., 2000). The use of biological polymers are advantageous in that they can block high permeability areas, are environmentally friendly, and have potential to form reversible gels without the use of hazardous cross-linkers. Recent efforts have produced a reactive alkaline-soluble biopolymer from Agrobacterium species ATCC # 31749 that gels upon decreasing the pH of the polymeric solution. Microbial polymers are of interest due to their potential cost savings, compared to conventional use of synthetic chemical polymers. Numerous microorganisms are known to produce extracellular polysaccharides. One microbiological polymer of interest is curdlan, â - (1, 3) glucan, which has demonstrated gelling properties by a reduction in pH. The focus of this study was to determine the impact an alkaline-soluble biopolymer can have on sandstone permeability.
Date: November 1, 2004
Creator: Fox, Sandra L.; Xie, Xina & Bala, Greg
Object Type: Article
System: The UNT Digital Library
Laser hazard analysis for LASIRIS Model MAG-501L-670M-1000-45[degree]-K diode laser associated with high resolution pulsed scanner. (open access)

Laser hazard analysis for LASIRIS Model MAG-501L-670M-1000-45[degree]-K diode laser associated with high resolution pulsed scanner.

A laser hazard analysis and safety assessment was performed for the LASIRISTM Model MAG-501L-670M-1000-45o-K diode laser associated with the High Resolution Pulse Scanner based on the ANSI Standard Z136.1-2000, American National Standard for the Safe Use of Lasers and the ANSI Standard Z136.6-2000, American National Standard for the Safe Use of Lasers Outdoors. The laser was evaluated for both indoor and outdoor use.
Date: November 1, 2004
Creator: Augustoni, Arnold L.
Object Type: Report
System: The UNT Digital Library
Modeling the transfer of land and water from agricultural to urban uses in the Middle Rio Grande Basin, New Mexico. (open access)

Modeling the transfer of land and water from agricultural to urban uses in the Middle Rio Grande Basin, New Mexico.

Social and ecological scientists emphasize that effective natural resource management depends in part on understanding the dynamic relationship between the physical and non-physical process associated with resource consumption. In this case, the physical processes include hydrological, climatological and ecological dynamics, and the non-physical process include social, economic and cultural dynamics among humans who do the resource consumption. This project represents a case study aimed at modeling coupled social and physical processes in a single decision support system. In central New Mexico, individual land use decisions over the past five decades have resulted in the gradual transformation of the Middle Rio Grande Valley from a primarily rural agricultural landscape to a largely urban one. In the arid southwestern U.S., the aggregate impact of individual decisions about land use is uniquely important to understand, because scarce hydrological resources will likely limit the viability of resulting growth and development trajectories. This decision support tool is intended to help planners in the area look forward in their efforts to create a collectively defined 'desired' social landscape in the Middle Rio Grande. Our research question explored the ways in which socio-cultural values impact decisions regarding that landscape and associated land use. Because of the constraints …
Date: November 1, 2004
Creator: Jarratt, Janet (Valencia County, NM); Passell, Howard David; Kelly, Susan (Utton Transboundary Resources Center, Albuquerque, NM); Malczynski, Leonard A.; Chermak, Janie (University of New Mexico, Albuquerque, NM); Van Bloeman Waanders, Paul (GRAM, Inc., Albuquerque, NM) et al.
Object Type: Report
System: The UNT Digital Library
Top Value Added Chemicals From Biomass: I. Results of Screening for Potential Candidates from Sugars and Synthesis Gas (open access)

Top Value Added Chemicals From Biomass: I. Results of Screening for Potential Candidates from Sugars and Synthesis Gas

This report identifies twelve building block chemicals that can be produced from sugars via biological or chemical conversions. The twelve building blocks can be subsequently converted to a number of high-value bio-based chemicals or materials. Building block chemicals, as considered for this analysis, are molecules with multiple functional groups that possess the potential to be transformed into new families of useful molecules. The twelve sugar-based building blocks are 1,4-diacids (succinic, fumaric and malic), 2,5-furan dicarboxylic acid, 3-hydroxy propionic acid, aspartic acid, glucaric acid, glutamic acid, itaconic acid, levulinic acid, 3-hydroxybutyrolactone, glycerol, sorbitol, and xylitol/arabinitol. In addition to building blocks, the report outlines the central technical barriers that are preventing the widespread use of biomass for products and chemicals.
Date: November 1, 2004
Creator: Werpy, Todd A.; Holladay, John E. & White, James F.
Object Type: Report
System: The UNT Digital Library
Multi-dimensional modeling of atmospheric copper-sulfidation corrosion on non-planar substrates. (open access)

Multi-dimensional modeling of atmospheric copper-sulfidation corrosion on non-planar substrates.

This report documents the author's efforts in the deterministic modeling of copper-sulfidation corrosion on non-planar substrates such as diodes and electrical connectors. A new framework based on Goma was developed for multi-dimensional modeling of atmospheric copper-sulfidation corrosion on non-planar substrates. In this framework, the moving sulfidation front is explicitly tracked by treating the finite-element mesh as a pseudo solid with an arbitrary Lagrangian-Eulerian formulation and repeatedly performing re-meshing using CUBIT and re-mapping using MAPVAR. Three one-dimensional studies were performed for verifying the framework in asymptotic regimes. Limited model validation was also carried out by comparing computed copper-sulfide thickness with experimental data. The framework was first demonstrated in modeling one-dimensional copper sulfidation with charge separation. It was found that both the thickness of the space-charge layers and the electrical potential at the sulfidation surface decrease rapidly as the Cu{sub 2}S layer thickens initially but eventually reach equilibrium values as Cu{sub 2}S layer becomes sufficiently thick; it was also found that electroneutrality is a reasonable approximation and that the electro-migration flux may be estimated by using the equilibrium potential difference between the sulfidation and annihilation surfaces when the Cu{sub 2}S layer is sufficiently thick. The framework was then employed to model copper …
Date: November 1, 2004
Creator: Chen, Ken Shuang
Object Type: Report
System: The UNT Digital Library
Microfabrication with femtosecond laser processing : (A) laser ablation of ferrous alloys, (B) direct-write embedded optical waveguides and integrated optics in bulk glasses. (open access)

Microfabrication with femtosecond laser processing : (A) laser ablation of ferrous alloys, (B) direct-write embedded optical waveguides and integrated optics in bulk glasses.

At Sandia National Laboratories, miniaturization dominates future hardware designs, and technologies that address the manufacture of micro-scale to nano-scale features are in demand. Currently, Sandia is developing technologies such as photolithography/etching (e.g. silicon MEMS), LIGA, micro-electro-discharge machining (micro-EDM), and focused ion beam (FIB) machining to fulfill some of the component design requirements. Some processes are more encompassing than others, but each process has its niche, where all performance characteristics cannot be met by one technology. For example, micro-EDM creates highly accurate micro-scale features but the choice of materials is limited to conductive materials. With silicon-based MEMS technology, highly accurate nano-scale integrated devices are fabricated but the mechanical performance may not meet the requirements. Femtosecond laser processing has the potential to fulfill a broad range of design demands, both in terms of feature resolution and material choices, thereby improving fabrication of micro-components. One of the unique features of femtosecond lasers is the ability to ablate nearly all materials with little heat transfer, and therefore melting or damage, to the surrounding material, resulting in highly accurate micro-scale features. Another unique aspect to femtosecond radiation is the ability to create localized structural changes thought nonlinear absorption processes. By scanning the focal point within …
Date: November 1, 2004
Creator: Guo, Junpeng; McDaniel, Karen Lynn; Palmer, Jeremy Andrew; Yang, Pin; Griffith, Michelle Lynn; Vawter, Gregory Allen et al.
Object Type: Report
System: The UNT Digital Library
Precision volume measurement system. (open access)

Precision volume measurement system.

A new precision volume measurement system based on a Kansas City Plant (KCP) design was built to support the volume measurement needs of the Gas Transfer Systems (GTS) department at Sandia National Labs (SNL) in California. An engineering study was undertaken to verify or refute KCP's claims of 0.5% accuracy. The study assesses the accuracy and precision of the system. The system uses the ideal gas law and precise pressure measurements (of low-pressure helium) in a temperature and computer controlled environment to ratio a known volume to an unknown volume.
Date: November 1, 2004
Creator: Fischer, Erin E. & Shugard, Andrew D.
Object Type: Report
System: The UNT Digital Library
Adaptive optics and phase diversity imaging for responsive space applications. (open access)

Adaptive optics and phase diversity imaging for responsive space applications.

The combination of phase diversity and adaptive optics offers great flexibility. Phase diverse images can be used to diagnose aberrations and then provide feedback control to the optics to correct the aberrations. Alternatively, phase diversity can be used to partially compensate for aberrations during post-detection image processing. The adaptive optic can produce simple defocus or more complex types of phase diversity. This report presents an analysis, based on numerical simulations, of the efficiency of different modes of phase diversity with respect to compensating for specific aberrations during post-processing. It also comments on the efficiency of post-processing versus direct aberration correction. The construction of a bench top optical system that uses a membrane mirror as an active optic is described. The results of characterization tests performed on the bench top optical system are presented. The work described in this report was conducted to explore the use of adaptive optics and phase diversity imaging for responsive space applications.
Date: November 1, 2004
Creator: Smith, Mark William & Wick, David Victor
Object Type: Report
System: The UNT Digital Library
Simulations of the interaction of intense petawatt laser pulses with dense Z-pinch plasmas : final report LDRD 39670. (open access)

Simulations of the interaction of intense petawatt laser pulses with dense Z-pinch plasmas : final report LDRD 39670.

We have studied the feasibility of using the 3D fully electromagnetic implicit hybrid particle code LSP (Large Scale Plasma) to study laser plasma interactions with dense, compressed plasmas like those created with Z, and which might be created with the planned ZR. We have determined that with the proper additional physics and numerical algorithms developed during the LDRD period, LSP was transformed into a unique platform for studying such interactions. Its uniqueness stems from its ability to consider realistic compressed densities and low initial target temperatures (if required), an ability that conventional PIC codes do not possess. Through several test cases, validations, and applications to next generation machines described in this report, we have established the suitability of the code to look at fast ignition issues for ZR, as well as other high-density laser plasma interaction problems relevant to the HEDP program at Sandia (e.g. backlighting).
Date: November 1, 2004
Creator: Welch, Dale Robert (Mission Research Corporation, Albuquerque, NM); MacFarlane, Joseph John (Prism Computational Sciences, Madison, WI); Mehlhorn, Thomas Alan & Campbell, Robert B.
Object Type: Report
System: The UNT Digital Library
Explosive Detection and Identification by PGNAA (open access)

Explosive Detection and Identification by PGNAA

The goal of this project was to determine the feasibility of using field-portable prompt gamma-ray neutron activation analysis (PGNAA) to detect and identify explosives in improvised nuclear devices (INDs). The studies were carried out using the Monte Carlo N-Particle (MCNP) code developed at Los Alamos National Laboratory. The model results were tested experimentally using explosive simulants and the PINS PGNAA system developed at Idaho National Engineering and Environmental Laboratory (INEEL). The results of the MCNP calculations and PINS measurements are presented in this report. The calculations and measurements were in good agreement and indicate that most explosives are readily distinguishable from one another.
Date: November 1, 2004
Creator: Seabury, E. H. & Caffrey, A. J.
Object Type: Report
System: The UNT Digital Library
Texas Attorney General Opinion: GA-0267 (open access)

Texas Attorney General Opinion: GA-0267

Document issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, Greg Abbott, regarding a legal question submitted for clarification; Whether, under section 54.012(5) of the Local Government Code, a municipality may enact an ordinance prescribing civil penalties for matters that do not relate to the substantive provisions of section 54.012 (RQ-0220-GA)
Date: November 1, 2004
Creator: Texas. Attorney-General's Office.
Object Type: Text
System: The Portal to Texas History
Insights into the Dynamic Response of Tunnels in Jointed Rocks (open access)

Insights into the Dynamic Response of Tunnels in Jointed Rocks

Tunnels in jointed rocks can be subjected to severe dynamic loads because of rock bursts, coal bumps, and large earthquakes. A series of 3-dimensional simulations was performed, based on discrete element analysis to gain insights into the parameters that influence the response of such tunnels. The simulations looked at the effect of joint set orientation, the effect of joint spacing, the effect of pulse shape for a given displacement, and the influence of using rigid versus deformable blocks in the analyses. The results of this modeling were also compared to field evidence of dynamic tunnel failures. This comparison reinforced the notion that 3-dimensional discrete element analysis can capture very well the kinematics of structures in jointed rock under dynamic loading.
Date: November 1, 2004
Creator: Heuze, F E
Object Type: Article
System: The UNT Digital Library