A pipelined IC architecture for radon transform computations in a multiprocessor array (open access)

A pipelined IC architecture for radon transform computations in a multiprocessor array

The amount of data generated by CT scanners is enormous, making the reconstruction operation slow, especially for 3-D and limited-data scans requiring iterative algorithms. The Radon transform and its inverse, commonly used for CT image reconstruction from projections, are computationally burdensome for today's single-processor computer architectures. If the processing times for the forward and inverse Radon transforms were comparatively small, a large set of new CT algorithms would become feasible, especially those for 3-D and iterative tomographic image reconstructions. In addition to image reconstruction, a fast Radon Transform Computer'' could be naturally applied in other areas of multidimensional signal processing including 2-D power spectrum estimation, modeling of human perception, Hough transforms, image representation, synthetic aperture radar processing, and others. A high speed processor for this operation is likely to motivate new algorithms for general multidimensional signal processing using the Radon transform. In the proposed workshop paper, we will first describe interpolation schemes useful in computation of the discrete Radon transform and backprojection and compare their errors and hardware complexities. We then will evaluate through statistical means the fixed-point number system required to accept and generate 12-bit input and output data with acceptable error using the linear interpolation scheme selected. These …
Date: May 25, 1990
Creator: Agi, I.; Hurst, P.J. & Current, K.W. (California Univ., Davis, CA (USA). Dept. of Electrical Engineering and Computer Science)
Object Type: Article
System: The UNT Digital Library
Health and safety guide for inorganic compounds and metals used in the fabrication of superconductive alloys (open access)

Health and safety guide for inorganic compounds and metals used in the fabrication of superconductive alloys

This health and safety guide was written to satisfy two objectives: to summarize the toxicity of metals and alloys used in superconductivity for the benefit of those who work with these materials, and to summarize and describes the basic principles of a highly technical field from a health and safety point-of-view for the benefit of health professionals. The guide begins with a profile of the superconductivity industry, including a list of current and potential applications, a literature review of the market potential, and summary of the current industry status. The body of the paper provides a toxicity and hazard summary for 50 metals, alloys and metal oxides used in superconductivity. The toxicity and hazard summary for all 50 compounds includes: occupational exposure limits, explosiveness and flammability potential, LD{sub 50}'s, chemical and physical properties, incompatibilities and reactivities, recommended personal protective equipment, symptoms of acute and chronic exposure, target organs and toxic effects, and steps for emergency first aid. Finally, a discussion of general occupational hygiene principles is provided, with emphasis on how these principles apply to the unique field of superconductivity. 41 refs.
Date: April 25, 1990
Creator: Arnold, S. D. & Talley, G. M.
Object Type: Article
System: The UNT Digital Library
(Working Team meeting of IEA-CADDET) (open access)

(Working Team meeting of IEA-CADDET)

The traveler serving as Delegate from the United States, Center for the Analysis and Dissemination of Demonstrated Energy, (CADDET) National Team, participated in the activities of the annual International Energy Agency, CADDET Working Team meeting. Highlights of this meeting included progress/status presentations by 12 to 13 CADDET National Teams, development of future CADDET work plans including a prioritization of activities, and discussions of long range expectations for CADDET. Follow-up discussions were held with CADDET staff members which focused on US CADDET National Team contributions to the CADDET newsletter, brochures and register of demonstrated energy technologies.
Date: October 25, 1990
Creator: Broders, M. A.
Object Type: Report
System: The UNT Digital Library
Kinetic models of hydrocarbon generation (open access)

Kinetic models of hydrocarbon generation

We are carrying out an integrated program of laboratory experiments, kinetics modeling, and basin thermal history modeling in order to better understand the natural breakdown of organic matter into oil and gas. Our kinetic models of organic maturation are being used to better understand the coupling of generation, cracking, expulsion, and overpressuring in both the laboratory and geologic setting. Currently we are carrying out chemical experiments and developing more efficient chemical kinetic modeling schemes to obtain a better understanding of expulsion and cracking from lean source rocks and from hydrogen-poor (terrestrial) organic source material. We verify the chemical kinetic models by integrating them with thermal history models of hydrocarbon-producing sediments and comparing predicted and observed characteristics of the hydrocarbon occurrence in a variety of settings. We intend to apply this approach to evaluate the potential for deep gas resources in the Pacific Northwest and in the Louisiana Gulf Coast. 11 refs., 4 figs.
Date: October 25, 1990
Creator: Burnham, A. K. & Sweeney, J. J.
Object Type: Article
System: The UNT Digital Library
Temperature Control Feedback Loops for the Linac Upgrade Side Coupled Cavities at Fermilab (open access)

Temperature Control Feedback Loops for the Linac Upgrade Side Coupled Cavities at Fermilab

The linac upgrade project at Fermilab will replace the last 4 drift-tube linac tanks with seven side coupled cavity strings. This will increase the beam energy from 200 to 400 MeV at injection into the Booster accelerator. The main objective of the temperature loop is to control the resonant frequency of the cavity strings. A cavity string will constant of 4 sections connected with bridge couplers driven with a 12 MW klystron at 805 MHz. Each section is a side coupled cavity chain consisting of 16 accelerating cells and 15 side coupling cells. For the linac upgrade, 7 full cavity strings will be used. A separate temperature control system is planned for each of the 28 accelerating sections, the two transition sections, and the debuncher section. The cavity strings will be tuned to resonance for full power beam loaded conditions. A separate frequency loop is planned that will sample the phase difference between a monitor placed in the end cell of each section and the rf drive. The frequency loop will control the set point for the temperature loop which will be able to maintain the resonant frequency through periods within beam or rf power. The frequency loop will need …
Date: October 25, 1990
Creator: Crisp, Jim
Object Type: Report
System: The UNT Digital Library
Report of Foreign Travel of Environmental Sciences Research Staff, August-September 1990 (open access)

Report of Foreign Travel of Environmental Sciences Research Staff, August-September 1990

the travelers attended the Fifth International Congress of Ecology (INTECOL) in Yokohama, Japan, and two presented invited papers and chaired symposia. One traveler also attended the OJI International Seminar in Gifu, Japan and the Fukuoka Symposium on Theoretical Ecology in Fukuoka, Japan and presented invited papers. At these scientific gatherings, a large number of symposia and specific presentations were relevant to current research at Oak Ridge National Laboratory (ORNL), especially in the areas of landscape dynamics, plant physiology, and aquatic ecosystems.
Date: September 25, 1990
Creator: DeAngelis, Donald L.; Garten, Charles T., Jr. & Turner, Monica G.
Object Type: Report
System: The UNT Digital Library
CRAF/Cassini Contingency Plans Using Only Existing Pu(superscript238) Inventory (open access)

CRAF/Cassini Contingency Plans Using Only Existing Pu(superscript238) Inventory

No Abstract. There are two duplicate copies. One is in the FSC-ESD files.
Date: October 25, 1990
Creator: Eck, Marshall B
Object Type: Report
System: The UNT Digital Library
Workshop on heavy ion physics at the AGS: Outlook (open access)

Workshop on heavy ion physics at the AGS: Outlook

This report presents the closing talk of the workshop on AGS heavy ion program held at BNL March 5--7, 1990. The emphasis is on new questions posed by the new data presented at this meeting with emphasis on the pion-proton puzzle. 10 refs., 1 fig., 1 tab.
Date: May 25, 1990
Creator: Gyulassy, M.
Object Type: Article
System: The UNT Digital Library
Computation at the edge of chaos: Phase transition and emergent computation (open access)

Computation at the edge of chaos: Phase transition and emergent computation

In order for computation to emerge spontaneously and become an important factor in the dynamics of a system, the material substrate must support the primitive functions required for computation: the transmission, storage, and modification of information. Under what conditions might we expect physical systems to support such computational primitives This paper presents research on Cellular Automata which suggests that the optimal conditions for the support of information transmission, storage, and modification, are achieved in the vicinity of a phase transition. We observe surprising similarities between the behaviors of computations and systems near phase-transitions, finding analogs of computational complexity classes and the Halting problem within the phenomenology of phase-transitions. We conclude that there is a fundamental connection between computation and phase-transitions, and discuss some of the implications for our understanding of nature if such a connection is borne out. 31 refs., 16 figs.
Date: January 25, 1990
Creator: Langton, C.
Object Type: Article
System: The UNT Digital Library
Status of the Relativistic Heavy Ion Collider (open access)

Status of the Relativistic Heavy Ion Collider

Accelerator Physics issues, such as the dynamical aperture, the beam lifetime and the current--intensity limitation are carefully studied for the Relativistic Heavy Ion Collider at Brookhaven National Laboratory. The single layer superconducting magnets, of 8 cm coil inner diameter, satisfying the beam stability requirements have also been successfully tested. The proposal has generated wide spread interest in the particle and nuclear physics. 1 ref., 4 figs., 3 tabs.
Date: April 25, 1990
Creator: Lee, S. Y.
Object Type: Article
System: The UNT Digital Library
Thermal analysis of the FSP-1 fuel pin irradiation test (open access)

Thermal analysis of the FSP-1 fuel pin irradiation test

Thermal analysis of a pin from the FSP-1 fuels irradiation test has been completed. The purpose of the analysis was to provide predictions of fuel pin temperatures, determine the flow regime within the lithium annulus of the test assembly, and provide a standardized model for a consistent basis of comparison between pins within the test assembly. The calculations have predicted that the pin is operating at slightly above the test design temperatures and that the flow regime within the lithium annulus is a laminar buoyancy driven flow. 7 refs., 5 figs.
Date: July 25, 1990
Creator: Lyon, W. F., III
Object Type: Article
System: The UNT Digital Library
EMPACT: Electrons Muons Partons with Air Core Toroids (open access)

EMPACT: Electrons Muons Partons with Air Core Toroids

The EMPACT experiment utilizes a broad approach to maximize its discovery potential for new phenomena accessible at the SSC. The high resolution detector has a balances emphasis on, and large acceptance for, electrons, muons, jets, and noninteracting particles, and is capable of utilizing the ultimate luminosity of the SSC. The detector emphasizes excellent calorimetry augmented by TRD tracking, and employs an innovative system of superconducting air core toroids for muon measurements. Significant engineering effort has established the feasibility of a baseline detector concept and has addressed the related issues of support facilities, assembly, and detector integration. The design has been tested against the challenges of predicted phenomena, with the expectation that this will optimize the capacity for observing the unexpected. EMPACT's international collaboration has unprecedented support from major aerospace industries who are providing tools and expertise for project design and integration, which will assure that a detector optimized for performance and cost will be available for the first collisions at the new laboratory.
Date: May 25, 1990
Creator: Marx, M. D.
Object Type: Report
System: The UNT Digital Library
Shot report, Holo-17-Holo-22 Rex-9 (open access)

Shot report, Holo-17-Holo-22 Rex-9

We report on a series of holographic shots using explosives to generate ejecta from lead. These experiments covered a range of geometries including point initiation and plane wave initiation for the H.E., and using a gas-fill in the cavity where the ejecta was produced. The final experiment, Rex-9 was a Fabry-Perot experiment at Site 300 which provided the velocity history of the lead surface for the purpose of normalizing the code being used to calculate the position of the lead surface in these experiments. The focus of this report is on the experimental technique rather than on the size measurements. We want to insure that the advances in mechanical design and experimental technique that were made during these experiments are preserved in future experiments. 8 figs., 2 tabs.
Date: October 25, 1990
Creator: McMillan, C.; Whipkey, R. & Vance, P.
Object Type: Report
System: The UNT Digital Library
Pump Outs, General and D0 Considerations (open access)

Pump Outs, General and D0 Considerations

Seal Pump Outs (PO) are provided by specifically designing and providing redundant, or double, seals to create an annular volume that can be '(vacuum) pumped out' to test the integrity of both seals. The value of the technique is most readily apparent in the construction of large piping systems or vessels whose closure is on a different schedule than the nozzle closures, or whose nozzles are serially closed. In the case of D0, for instance, the high voltage boxes were put in place and leak checked before the vessel was closed and independent of the other nozzles. PO use is by no means limited to cryogenics and the supporting vacuum systems, but the discussion here will be limited to cryogenic applications. POs come in two generic service types; installation, and installation and monitor. The above high voltage box is an example of a static installation service application. Once the item is installed the PO can be, and almost universally is, capped, and revisited only on disassembly and reassembly. POs are constantly monitored after installation only when their seals, through cooldown gradient induced motion, vibration, cyclic load bolt seating, or other dynamic phenomena may degrade in performance over time. PO seals …
Date: December 25, 1990
Creator: Mulholland, G.T.
Object Type: Report
System: The UNT Digital Library
Heavy metal contamination in TIMS Branch sediments (open access)

Heavy metal contamination in TIMS Branch sediments

The objective of this memorandum is to summarize results of previous sediment studies on Tims Branch and Steed`s Pond conducted by Health Protection (HP) and by the Savannah River Laboratory (SRL) in conjunction with Reactor Materials Engineering & Technology (RMET). The results for other heavy metals, such as lead, nickel, copper, mercury, chromium, cadmium, zinc, and thorium are also summarized.
Date: June 25, 1990
Creator: Pickett, J. B.
Object Type: Report
System: The UNT Digital Library
Heavy metal contamination in TIMS Branch sediments (open access)

Heavy metal contamination in TIMS Branch sediments

The objective of this memorandum is to summarize results of previous sediment studies on Tims Branch and Steed's Pond conducted by Health Protection (HP) and by the Savannah River Laboratory (SRL) in conjunction with Reactor Materials Engineering Technology (RMET). The results for other heavy metals, such as lead, nickel, copper, mercury, chromium, cadmium, zinc, and thorium are also summarized.
Date: June 25, 1990
Creator: Pickett, J.B.
Object Type: Report
System: The UNT Digital Library
HFBR: Review of the technical specifications against the FSAR (open access)

HFBR: Review of the technical specifications against the FSAR

The purpose of this review is to determine the adequacy of the High Flux Beam Reactor (HFBR) Technical Specifications for 40 MW operation by comparison with the HFBR Final Safety Analysis Report, particularly the accident analyses chapter. Specifically, the Technical Specifications were compared against the Design Basis Accident (DBA) Analyses presented in the Addendum to the HFBR FSAR for 60 MW Operation. The 60 MW DBA analyses was used since it is more current and complete than the analyses presented in the original FSAR which is considered obsolete. A listing of the required systems and equipment was made for each of the accidents analyzed. Additionally, the Technical Specification instrument setpoints were compared to the DBA analyses parametric values. Also included in this review was a comparison of the Technical Specification Bases against the FSAR and the identification of any differences. The HFBR Operations Procedures Manual (OPM) was also reviewed for any inconsistencies between the FSAR or the Technical Specifications. Upon completion of this review it was determined that the Technical Specifications are well written and the items commented on should not delay the low power restart (40 MW). Additionally, the OPM is also well written and does not require further …
Date: January 25, 1990
Creator: Rao, D. V.; Ross, S. B.; Claiborne, E. R.; Darby, J. L. & Clark, R. A.
Object Type: Report
System: The UNT Digital Library
D-Zero Central Calorimeter Pressure Vessel and Vacuum Vessel Safety Notes (open access)

D-Zero Central Calorimeter Pressure Vessel and Vacuum Vessel Safety Notes

The relief valve and relief piping capacity was calculated to be 908 sefm air. This exceeds all relieving conditions. The vessel also has a rupture disc with a 2640 scfm air stamped capacity. In order to significantly decrease the amount of time required to fill the cryostats, it is desired to raise the setpoint of the 'operating' relief valve on the argon storage dewar to 20 psig from its existing 16 psig setting. This additional pressure increases the flow to the cryostats and will overwhelm the relief capacity if the temperature of the modules within these vessels is warm enough. Using some conservative assumptions and simple calculations within this note, the maximum average temperature that the modules within each cryostat can be at prior to filling from the storage dewar with liquid argon is at least 290 K. The average temperature of the module mass for any of the three cryostats can be as high as 290 K prior to filling that particular cryostat. This should not be confused with the average temperature of a single type or location which is useful in protecting the modules-not necessarily the vessel itself. A few modules of each type and at different elevations …
Date: October 25, 1990
Creator: Rucinski, R. & Luther, R.
Object Type: Report
System: The UNT Digital Library
Molecular iodine absolute frequencies. Final report (open access)

Molecular iodine absolute frequencies. Final report

Fifty specified lines of {sup 127}I{sub 2} were studied by Doppler-free frequency modulation spectroscopy. For each line the classification of the molecular transition was determined, hyperfine components were identified, and one well-resolved component was selected for precise determination of its absolute frequency. In 3 cases, a nearby alternate line was selected for measurement because no well-resolved component was found for the specified line. Absolute frequency determinations were made with an estimated uncertainty of 1.1 MHz by locking a dye laser to the selected hyperfine component and measuring its wave number with a high-precision Fabry-Perot wavemeter. For each line results of the absolute measurement, the line classification, and a Doppler-free spectrum are given.
Date: June 25, 1990
Creator: Sansonetti, C. J.
Object Type: Report
System: The UNT Digital Library
FY90 milestone report for the CIT (Compact Ignition Tokamak) project: Localizability of electron-cyclotron heating power (open access)

FY90 milestone report for the CIT (Compact Ignition Tokamak) project: Localizability of electron-cyclotron heating power

Estimates of the localizability of electron-cyclotron heating power are made for the Compact Ignition Tokamak. A particular heating scenario is examined, namely, the fundamental O-mode, injected nearly perpendicular to the toroidal magnetic field. The absorption depth due to finite T{sub e} is very small, about 1 cm, near the q = 2 surface. Absorption is even better localized near q = 1. Several issues that might lead to degraded localizability are reviewed. Use of an intense, pulsed microwave source is the only issue with a possibly significant impact. 3 refs.
Date: October 25, 1990
Creator: Smith, G. R.
Object Type: Report
System: The UNT Digital Library
(Fuel, fission product, and graphite technology) (open access)

(Fuel, fission product, and graphite technology)

Travel to the Forschungszentrum (KFA) -- Juelich described in this report was for the purpose of participating in the annual meeting of subprogram managers for the US/DOE Umbrella Agreement for Fuel, Fission Product, and Graphite Technology. At this meeting the highlights of the cooperative exchange were reviewed for the time period June 1989 through June 1990. The program continues to contribute technology in an effective way for both countries. Revision 15 of the Subprogram Plan will be issued as a result of the meeting. There was interest expressed by KFA management in the level of support received from the NPR program and in potential participation in the COMEDIE loop experiment being conducted at the CEA.
Date: July 25, 1990
Creator: Stansfield, O.M.
Object Type: Report
System: The UNT Digital Library
Texas Attorney General Opinion: JM-1166 (open access)

Texas Attorney General Opinion: JM-1166

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, Jim Mattox, regarding a legal question submitted for clarification: Use of controlled substances as "bait" in a sting operation (RQ-1928)
Date: April 25, 1990
Creator: Texas. Attorney-General's Office.
Object Type: Text
System: The Portal to Texas History
Texas Attorney General Opinion: JM-1167 (open access)

Texas Attorney General Opinion: JM-1167

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, Jim Mattox, regarding a legal question submitted for clarification: Status of insurance programs in which applicants are referred, for a fee, to a single health care provider (RQ-1867)
Date: April 25, 1990
Creator: Texas. Attorney-General's Office.
Object Type: Text
System: The Portal to Texas History
Texas Attorney General Opinion: JM-1180 (open access)

Texas Attorney General Opinion: JM-1180

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, Jim Mattox, regarding a legal question submitted for clarification: Applicability of the Charitable Raffle Enabling Act, article 179f, V. T. C. S., to a nonprofit corporation whose purpose is to oppose construction of a landfill (RQ-1962)
Date: October 25, 1990
Creator: Texas. Attorney-General's Office.
Object Type: Text
System: The Portal to Texas History