Monte Carlo modeling of neutron and gamma-ray imaging systems (open access)

Monte Carlo modeling of neutron and gamma-ray imaging systems

Detailed numerical prototypes are essential to design of efficient and cost-effective neutron and gamma-ray imaging systems. We have exploited the unique capabilities of an LLNL-developed radiation transport code (COG) to develop code modules capable of simulating the performance of neutron and gamma-ray imaging systems over a wide range of source energies. COG allows us to simulate complex, energy-, angle-, and time-dependent radiation sources, model 3-dimensional system geometries with ``real world`` complexity, specify detailed elemental and isotopic distributions and predict the responses of various types of imaging detectors with full Monte Carlo accuray. COG references detailed, evaluated nuclear interaction databases allowingusers to account for multiple scattering, energy straggling, and secondary particle production phenomena which may significantly effect the performance of an imaging system by may be difficult or even impossible to estimate using simple analytical models. This work presents examples illustrating the use of these routines in the analysis of industrial radiographic systems for thick target inspection, nonintrusive luggage and cargoscanning systems, and international treaty verification.
Date: April 1, 1996
Creator: Hall, J.
Object Type: Article
System: The UNT Digital Library
Hazard classification of environmental restoration activities at the INEL (open access)

Hazard classification of environmental restoration activities at the INEL

The following documents require that a hazard classification be prepared for all activities for which US Department of Energy (DOE) has assumed environmental, safety, and health responsibility: the DOE Order 5481.1B, Safety Analysis and Review System and DOE Order 5480.23, Nuclear Safety Analysis Reports. A hazard classification defines the level of hazard posed by an operation or activity, assuming an unmitigated release of radioactive and nonradioactive hazardous material. For environmental restoration activities, the release threshold criteria presented in Hazard Baseline Documentation (DOE-EM-STD-5502-94) are used to determine classifications, such as Radiological, Nonnuclear, and Other Industrial facilities. Based upon DOE-EM-STD-5502-94, environmental restoration activities in all but one of the sites addressed by the scope of this classification (see Section 2) can be classified as ``Other Industrial Facility``. DOE-EM-STD-5502-94 states that a Health and Safety Plan and compliance with the applicable Occupational Safety and Health Administration (OSHA) standards are sufficient safety controls for this classification.
Date: April 1, 1996
Creator: Peatross, R. G.
Object Type: Report
System: The UNT Digital Library
A compilation of reports of the Advisory Committee on Reactor Safeguards: 1995 annual. Volume 17 (open access)

A compilation of reports of the Advisory Committee on Reactor Safeguards: 1995 annual. Volume 17

This compilation contains 44 ACRS reports submitted to the Commission, or to the Executive Director for Operations, during calendar year 1995. It also includes a report to the Congress on the NRC Safety Research Program. All reports have been made available to the public through the NRC Public Document Room and the US Library of Congress. The reports are divided into two groups: Part 1: ACRS Reports on Project Reviews, and Part 2: ACRS Reports on Generic Subjects. Part 1 contains ACRS reports by project name and by chronological order within project name. Part 2 categorizes the reports by the most appropriate generic subject area and by chronological order within subject area.
Date: April 1, 1996
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Neotectonics and seismicity of the Clearlake region in northern California (open access)

Neotectonics and seismicity of the Clearlake region in northern California

Geological, topographic, and seismic methods were used to locate faults in the vicinity of Clearlake in northern California. The geological method, which seeks faults as discontinuities in the lithotope, found faults in the Tertiary-Cretaceous rocks east of Burns Valley. The topographic method, which is used to produce Fault Evaluation Reports, found a very active fault zone, the Konocti Bay fault zone, south of Highlands arm. It also found some active faults north of Highlands arm, in the eastern part of Burns Valley and on the lakeshore near Oak Park. The seismic method is the most enduring of the three methods but is limited by location accuracy; the results improve as monitoring continues because of increases in the density of events and improvements in the crustal velocity model. The seismic method identified faulting along the valley at Borax Lake and possibly also on a line running northeast from the city of Clearlake. The latter may be associated with the Burns Valley fault or with the line of scoria domes which runs parallel to it. Seismic observations over longer periods at higher resolution will be required in order to determine the location of active faults near the city. 47 refs., 13 figs.
Date: April 1, 1996
Creator: Burns, K.L.
Object Type: Report
System: The UNT Digital Library
Development of tools for safety analysis of control software in advanced reactors (open access)

Development of tools for safety analysis of control software in advanced reactors

Software based control systems have gained a pervasive presence in a wide variety of applications, including nuclear power plant control and protection systems which are within the oversight and licensing responsibility of the US Nuclear Regulatory Commission. While the cost effectiveness and flexibility of software based plant process control is widely recognized, it is very difficult to achieve and prove high levels of demonstrated dependability and safety assurance for the functions performed by process control software, due to the very flexibility and potential complexity of the software itself. The development of tools to model, analyze and test software design and implementations in the context of the system that the software is designed to control can greatly assist the task of providing higher levels of assurance than those obtainable by software testing alone. This report presents and discusses the development of the Dynamic Flowgraph Methodology (DFM) and its application in the dependability and assurance analysis of software-based control systems. The features of the methodology and full-scale examples of application to both generic process and nuclear power plant control systems are presented and discussed in detail. The features of a workstation software tool developed to assist users in the application of DFM …
Date: April 1, 1996
Creator: Guarro, S.; Yau, M. & Motamed, M.
Object Type: Report
System: The UNT Digital Library
Magnetic inelastic scattering: Present results and future trends (open access)

Magnetic inelastic scattering: Present results and future trends

Experience over the last 15 years has shsown that pulsed neutron spectrometers are able to contribute to the field of magnetic inelastic scattering. Such spectrometers have high resolution and wide dynamic range, both of which are necessary in order to characterize the magnetic response of the complex systems of current interest, ranging from rare earth-transition metal permanent magnets to quantum critical scatterers. Howevera, all these studies have been constrained by current flux limitations. The development of more powerful spallation neutron sources, such as the JHP, is likely to transform these interesting demonstrations of the potential of pulsed neutron scattering into routine tools for the study of magnetic correlations.
Date: April 1996
Creator: Osborn, R.
Object Type: Article
System: The UNT Digital Library
Design, manufacture, and calibration of infrared radiometric blackbody sources (open access)

Design, manufacture, and calibration of infrared radiometric blackbody sources

A Radiometric Calibration Station (RCS) is being assembled at the Los Alamos National Laboratories (LANL) which will allow for calibration of sensors with detector arrays having spectral capability from about 0.4-15 {mu}m. The configuration of the LANL RCS. Two blackbody sources have been designed to cover the spectral range from about 3-15 {mu}m, operating at temperatures ranging from about 180-350 K within a vacuum environment. The sources are designed to present a uniform spectral radiance over a large area to the sensor unit under test. The thermal uniformity requirement of the blackbody cavities has been one of the key factors of the design, requiring less than 50 mK variation over the entire blackbody surface to attain effective emissivity values of about 0.999. Once the two units are built and verified to the level of about 100 mK at LANL, they will be sent to the National Institute of Standards and Technology (NIST), where at least a factor of two improvement will be calibrated into the blackbody control system. The physical size of these assemblies will require modifications of the existing NIST Low Background Infrared (LBIR) Facility. LANL has constructed a bolt-on addition to the LBIR facility that will allow calibration …
Date: April 1, 1996
Creator: Byrd, D. A.; Michaud, F. D. & Bender, S. C.
Object Type: Article
System: The UNT Digital Library
The FALSTF last-flight computer program (open access)

The FALSTF last-flight computer program

FALSTF is a computer program used with the DORT transport code to calculate fluxes and doses at detector points located outside the DORT geometry model. An integral form of the transport equation is solved to obtain the flux at the detector points resulting from the uncollided transport of the emergent particle density within the geometry as calculated by DORT. Both R-Z and R-{theta} geometries are supported.
Date: April 1, 1996
Creator: Childs, R. L.
Object Type: Article
System: The UNT Digital Library
LLNL line-item construction projects Master Site Plan (open access)

LLNL line-item construction projects Master Site Plan

This interim submittal is an updated 1996 overview of the Master Plan based on the 1995 LLNL Site Development Plan, illustrating the future land use considerations, and the locations of proposed facilities as documented through the line item development process and keyed to the summary table. The following components in addition to the line-item proposals remain key elements in the implementation strategy of the Master Plan: personnel migration, revitalization, space reduction, classified core contraction, utility systems, and environmental restoration.
Date: April 15, 1996
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Development of a video-based slurry sensor for on-line ash analysis. Sixth quarterly technical progress report, January 1, 1996--March 31, 1996 (open access)

Development of a video-based slurry sensor for on-line ash analysis. Sixth quarterly technical progress report, January 1, 1996--March 31, 1996

Automatic control of fine coal cleaning circuits has traditionally been limited by the lack of sensors for on-line ash analysis. Although several nuclear-based analyzers are available, none have seen widespread acceptance. This is largely due to the fact that nuclear sensors are expensive and tend to be influenced by changes in seam type and pyrite content. Recently, researchers at VPI&SU have developed an optical sensor for phosphate analysis. The sensor uses image processing technology to analyze video images of phosphate ore. It is currently being used by PCS Phosphate for off-line analysis of dry flotation concentrate. The primary advantages of optical sensors over nuclear sensors are that they are significantly cheaper, are not subject to measurement variations due to changes in high atomic number minerals, are inherently safer and require no special radiation permitting. The purpose of this work is to apply the knowledge gained in the development of an optical phosphate analyzer to the development of an on-line ash analyzer for fine coal slurries. During the past quarter, calibration tests were conducted on-site at the Middle Fork coal preparation plant owned and operated by Pittston Coal Company. After several plant visits, a consistent sensor calibration was obtained with approximately …
Date: April 28, 1996
Creator: Adel, G. T. & Luttrell, G. H.
Object Type: Report
System: The UNT Digital Library
NFRC spectral data library No. 3 for use with the WINDOW 4.1 computer program (open access)

NFRC spectral data library No. 3 for use with the WINDOW 4.1 computer program

This library update file contains NFRC approved spectral data for the WINDOW analysis program. This information is an update library that is distributed with WINDOW 4.1 and supercedes the NFRC Spectral Data Library Update of February 1996.
Date: April 1996
Creator: Rubin, M.
Object Type: Report
System: The UNT Digital Library
Structure functions of electroweak boson and leptons (open access)

Structure functions of electroweak boson and leptons

The QCD structure of the electroweak bosons is reviewed and the lepton structure function is defined and calculated. The leading order splitting functions of electron into quarks are extracted, showing an important contribution from {gamma}-Z interference. Leading logarithmic QCD evolution equations are constructed and solved in the asymptotic region where log{sup 2} behavior of the Parton densities is observed. Possible applications with clear manifestation of ``resolved`` photon and weak bosons are discussed. 8 refs., 3 figs.
Date: April 2, 1996
Creator: Slominski, W & Szwed, J.
Object Type: Article
System: The UNT Digital Library
Dual-rod Cr:LiSAF oscillator/amplifier for remote sensing applications (open access)

Dual-rod Cr:LiSAF oscillator/amplifier for remote sensing applications

A dual rod configuration is used to achieve 16W average power operation from a flashlamp-pumped Cr:LiSAF laser oscillator. A double-pass dual-rod amplifier configuration was used to amplify 141{mu}J pulses from a Q-switched diode-pumped LiSAF oscillator by a factor of {approximately}120. This experiment established a small signal gain of 13.4% per cm at 820 nm. Improved slope efficiency (7.4% electrical-to-light) and pulse repetition frequency (40Hz) were achieved with a single-rod oscillator using improved Cr:LiSAF material.
Date: April 1996
Creator: Early, J. W.; Lester, C. S. & Cockroft, N. J.
Object Type: Article
System: The UNT Digital Library
West Hackberry Tertiary Project. Quarterly technical progress report, January 1, 1996--March 31, 1996 (open access)

West Hackberry Tertiary Project. Quarterly technical progress report, January 1, 1996--March 31, 1996

The goal of the West Hackberry Tertiary Project is to demonstrate the technical and economic feasibility of combining air injection with the Double Displacement Process for tertiary oil recovery. The Double Displacement Process is the gas displacement of a water invaded oil column for the purpose of recovering oil through gravity drainage. The novel aspect of this project is the use of air as the injection fluid. The target reservoir for the project is the Camerina C-1,2,3 sand located on the West Flank of West Hackberry Field in Cameron Parish, Louisiana. If successful, this project will demonstrate that the use of air injection in the Double Displacement Process can economically recover oil in reservoirs where tertiary oil recovery is presently uneconomic. The first quarter of 1996 was outstanding both in terms of volume of air injected and low cost operations. More air was injected during this quarter than in any preceding quarter. The compressors experienced much improved run time with minimal repairs. Low operating costs resulted from no repairs required for injection or production wells. A discussion of the following topics are contained herein: (1) performance summary for the injection and production wells, (2) air compressor operations, (3) updated bottom …
Date: April 10, 1996
Creator: Gillham, T.; Cerveny, B. & Turek, E.
Object Type: Report
System: The UNT Digital Library
Relabeling symmetries in hydrodynamics and magnetohydrodynamics (open access)

Relabeling symmetries in hydrodynamics and magnetohydrodynamics

Lagrangian symmetries and concomitant generalized Bianchi identities associated with the relabeling of fluid elements are found for hydrodynamics and magnetohydrodynamics (MHD). In hydrodynamics relabeling results in Ertel`s theorem of conservation of potential vorticity, while in MHD it yields the conservation of cross helicity. The symmetries of the reduction from Lagrangian (material) to Eulerian variables are used to construct the Casimir invariants of the Hamiltonian formalism.
Date: April 1, 1996
Creator: Padhye, N. & Morrison, P.J.
Object Type: Report
System: The UNT Digital Library
National Ignition Facility project acquisition plan (open access)

National Ignition Facility project acquisition plan

The purpose of this National Ignition Facility Acquisition Plan is to describe the overall procurement strategy planned for the National Ignition Facility (NIF) Project. The scope of the plan describes the procurement activities and acquisition strategy for the following phases of the NIF Project, each of which receives either plant and capital equipment (PACE) or other project cost (OPC) funds: Title 1 and 2 design and Title 3 engineering (PACE); Optics manufacturing facilitization and pilot production (OPC); Convention facility construction (PACE); Procurement, installation, and acceptance testing of equipment (PACE); and Start-up (OPC). Activities that are part of the base Inertial Confinement Fusion (ICF) Program are not included in this plan. The University of California (UC), operating Lawrence Livermore National Laboratory (LLNL) and Los Alamos National Laboratory, and Lockheed-Martin, which operates Sandia National Laboratory (SNL) and the University of Rochester Laboratory for Laser Energetics (UR-LLE), will conduct the acquisition of needed products and services in support of their assigned responsibilities within the NIF Project structure in accordance with their prime contracts with the Department of Energy (DOE). LLNL, designated as the lead Laboratory, will have responsibility for all procurements required for construction, installation, activation, and startup of the NIF.
Date: April 1, 1996
Creator: Callaghan, R.W.
Object Type: Report
System: The UNT Digital Library
Strange particle production in hadronic Z{sup 0} decays (open access)

Strange particle production in hadronic Z{sup 0} decays

A study has been made of neutral strange baryons and pseudoscalar mesons produced in hadronic decays of the weak gauge boson V. The experiment was performed at the Stanford Linear Accelerator Center, which has the unique capability of colliding highly polarized electrons with unpolarized positrons. Overall production rates and spectra of the K{sup 0} and the {Lambda}{sup 0} (+{Lambda}{sup 0}) were measured and compared with other experiments as well as with Quantum Chromodynamics calculations. The combination of the small, stable beam spots produced by the SLAC Linear Collider (SLC) and the precision vertexing capabilities of the SLC Large Detector (SLD) permitted the separation of the hadronic events into three quark flavor-enriched samples. An unfolding was performed to obtain flavor-pure samples, and for the first time measurements were made of K{sup 0} and {Lambda}{sup 0} (+{Lambda}{sup 0}) production rates and spectra in uds, c, and b quark events at the Z{sup 0} pole. This measurement revealed significant production differences. Utilizing the large quark production asymmetry due to the polarized electron beam, high-purity quark and antiquark jet samples were obtained. The first measurement of production differences of the {Lambda}{sup 0} baryon in quark and antiquark jets was performed, which provided clear evidence …
Date: April 1, 1996
Creator: Baird, K.G. III
Object Type: Report
System: The UNT Digital Library
Development of Green Box sensor module technologies for rail applications (open access)

Development of Green Box sensor module technologies for rail applications

Results of a joint Sandia National Laboratories, University of New Mexico, and New Mexico Engineering Research Institute project to investigate an architecture implementing real-time monitoring and tracking technologies in the railroad industry is presented. The work, supported by the New Mexico State Transportation Authority, examines a family of smart sensor products that can be tailored to the specific needs of the user. The concept uses a strap-on sensor package, designed as a value-added component, integrated into existing industry systems and standards. Advances in sensor microelectronics and digital signal processing permit us to produce a class of smart sensors that interpret raw data and transmit inferred information. As applied to freight trains, the sensors` primary purpose is to minimize operating costs by decreasing losses due to theft, and by reducing the number, severity, and consequence of hazardous materials incidents. The system would be capable of numerous activities including: monitoring cargo integrity, controlling system braking and vehicle acceleration, recognizing component failure conditions, and logging sensor data. A cost-benefit analysis examines the loss of revenue resulting from theft, hazardous materials incidents, and accidents. Customer survey data are combined with the cost benefit analysis and used to guide the product requirements definition for a …
Date: April 1, 1996
Creator: Rey, D.; Breeding, R.; Hogan, J.; Mitchell, J.; McKeen, R.G. & Brogan, J.
Object Type: Report
System: The UNT Digital Library
Scale-up of miscible flood processes for heterogeneous reservoirs. Final report (open access)

Scale-up of miscible flood processes for heterogeneous reservoirs. Final report

Results of a wide-ranging investigation of the scaling of gas injection processes are reported. The research examines how the physical mechanisms at work during a gas injection project interact to determine process performance. In particular, the authors examine: the interactions of equilibrium phase behavior and two-phase flow that determine local displacement efficiency and minimum miscibility pressure, the combined effects of viscous fingering, gravity segregation and heterogeneity that control sweep efficiency in 2- and 3-dimensional porous media, the use of streamtube/streamline methods to create very efficient simulation technique for multiphase compositional displacements, the scaling of viscous, capillary and gravity forces for heterogeneous reservoirs, and the effects of the thin films and spreading behavior on three-phase flow. The following key results are documented: rigorous procedures for determination of minimum miscibility pressure (MMP) or minimum miscibility enrichment (MME) for miscibility have been developed for multicomponent systems; the complex dependence of MMP`s for nitrogen/methane floods on oil and injection gas composition observed experimentally is explained for the first time; the presence of layer-like heterogeneities strongly influences the interplay of gravity segregation and viscous fingering, as viscous fingers adapt to preferential flow paths and low permeability layers restrict vertical flow; streamtube/streamline simulation techniques are demonstrated …
Date: April 1, 1996
Creator: Orr, F.M. Jr.
Object Type: Report
System: The UNT Digital Library
Design predictions and diagnostic test methods for hydronic heating systems in ASHRAE standard 152P (open access)

Design predictions and diagnostic test methods for hydronic heating systems in ASHRAE standard 152P

A new method of test for residential thermal distribution efficiency is currently being developed under the auspices of the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE). The initial version of this test method is expected to have two main approaches, or ``pathways,`` designated Design and Diagnostic. The Design Pathway will use builder`s information to predict thermal distribution efficiency in new construction. The Diagnostic Pathway will use simple tests to evaluate thermal distribution efficiency in a completed house. Both forced-air and hydronic systems are included in the test method. This report describes an approach to predicting and measuring thermal distribution efficiency for residential hydronic heating systems for use in the Design and Diagnostic Pathways of the test method. As written, it is designed for single-loop systems with any type of passive radiation/convection (baseboard or radiators). Multiloop capability may be added later.
Date: April 1, 1996
Creator: Andrews, J. W.
Object Type: Report
System: The UNT Digital Library
Laser ablation of graphite in different buffer gases (open access)

Laser ablation of graphite in different buffer gases

The KrF-laser ablation of graphite into 300 Torr of He, Ne, Ar, and Xe has been studied by fast imaging of the plasma emission and post-deposition analyses of collected film deposits. In each case, the soot which was redeposited on the irradiated rod following ablation was highly fullerene-deficient compared to the material collected on the sample disk 1.5 cm from the rod, as determined by laser desorption Fourier Transform Mass Spectrometry (FTMS) Investigation of the plasma plume propagation using fast ICCD photography reveals three main phases to the expansion: (1) forward motion, deceleration and stopping of the leading edge of the plume, (2) an apparent reflected shock within the plume which propagates backward and reflects from the rod surface, (3) coalescence of these two components, resulting in continued expansion and dissipation of the plasma and the appearance of glowing ultrafine particles. For the laser plume propagating in 300 Torr of Xe the characteristic time intervals for these three phases are 0-300 ns, 300-1000 ns, and 1-1000 {mu}s for phases (1), (2), and (3) respectively. The possible explanation of the observed difference in fullerene content is discussed on the basis of different plasma phases resulting in soot deposition on the rod …
Date: April 1996
Creator: Puretzky, A. A.; Geohegan, D. B. & Haufler, R. E.
Object Type: Article
System: The UNT Digital Library
Adaptive smoothing techniques for 3-D unstructured meshes (open access)

Adaptive smoothing techniques for 3-D unstructured meshes

To correctly capture the behavior of deforming material volumes in 3-D, the Los Alamos unstructured grid code X3D has access to a variety of moving mesh algorithms. The authors present two such algorithms which markedly differ in their computational complexity. The first algorithm, Moving finite Elements for Surfaces, has only 2-D computational complexity, in that they only solve for interface motions and obtain volume point motions through interpolation. The second algorithm, Minimum Error Gradient Adaption, has 3-D complexity, since the volume tetrahedral deformations must be computed. Naturally, the 3-D complexity algorithm can model realistically a larger class of physical problems than the lower complexity approach. They present examples in metallic grain growth and semiconductor process modeling.
Date: April 1, 1996
Creator: Kuprat, A.
Object Type: Report
System: The UNT Digital Library
Current and projected liquid low-level waste generation at ORNL (open access)

Current and projected liquid low-level waste generation at ORNL

Liquid low-level waste (LLLW) is generated by various programs and projects throughout Oak Ridge National Laboratory (ORNL). This waste is collected in bottles, by trucks, or in underground collection tanks; it is then neutralized with sodium hydroxide and reduced in volume at the ORNL LLLW evaporator. This report presents historical and projected data concerning the volume and the characterization of LLLW, both prior to and after evaporation. Storage space for projected waste generation is also discussed.
Date: April 1996
Creator: DePaoli, S. M. & West, G. D.
Object Type: Report
System: The UNT Digital Library
Nonequilibrium sulfur capture and retention in an air cooled slagging coal combustor. Second quarterly technical progress report, January 1, 1996--March 31, 1996 (open access)

Nonequilibrium sulfur capture and retention in an air cooled slagging coal combustor. Second quarterly technical progress report, January 1, 1996--March 31, 1996

The objective of this 24 month project is to determine the degree of sulfur retention in slag in a full scale cyclone coal combustor. This effort will consist of a series of up to 20 parametric tests in a 20 MMBtu/hr slagging, air cooled, cyclone combustor. During the present reporting period, this combustor was tested for a total of 9 days in February and at the end of March. The tests at the end of March were the first ones in which excellent slagging combustor operation was achieved. This is the key requirement for implementing the test effort in the present project. Therefore, the combustor is now ready for testing under the current project, and initial tests are planned during the next quarterly reporting period, as per the project schedule.
Date: April 8, 1996
Creator: Zauderer, B.
Object Type: Report
System: The UNT Digital Library