A 1200 element detector system for synchrotron-based coronary angiography (open access)

A 1200 element detector system for synchrotron-based coronary angiography

A 1200 channel Si(Li) detector system has been developed for transvenous coronary angiography experiments using synchrotron radiation. It is part of the synchrotron medical imaging facility at the National Synchrotron Light Source. The detector is made from a single crystal of lithium-drifted silicon with an active area 150 mm long {times} 11 mm high {times} 5 mm thick. The elements are arranged in two parallel rows of 600 elements with a center-to-center spacing of 0.25 mm. All 1200 elements are read out simultaneously every 4 ms. A Intel 80486 based computer with a high speed digital signal processing interface is used to control the beamline hardware and to acquire a series of images. The signal-to-noise, linearity and resolution of the system have been measured. Human images have been taken with this system.
Date: August 23, 1993
Creator: Thompson, A. C.; Lavender, W. M.; Rubenstein, E.; Giacomini, J. C.; Rosso, V.; Schulze, C. et al.
Object Type: Article
System: The UNT Digital Library
Argonne National Laboratory: Laboratory Directed Research and Development FY 1993 program activities. Annual report (open access)

Argonne National Laboratory: Laboratory Directed Research and Development FY 1993 program activities. Annual report

The purposes of Argonne`s Laboratory Directed Research and Development (LDRD) Program are to encourage the development of novel concepts, enhance the Laboratory`s R&D capabilities, and further the development of its strategic initiatives. Projects are selected from proposals for creative and innovative R&D studies which are not yet eligible for timely support through normal programmatic channels. Among the aims of the projects supported by the Program are establishment of engineering ``proof-of-principle`` assessment of design feasibility for prospective facilities; development of an instrumental prototype, method, or system; or discovery in fundamental science. Several of these projects are closely associated with major strategic thrusts of the Laboratory as described in Argonne`s Five Year Institutional Plan, although the scientific implications of the achieved results extend well beyond Laboratory plans and objectives. The projects supported by the Program are distributed across the major programmatic areas at Argonne as indicated in the Laboratory LDRD Plan for FY 1993.
Date: December 23, 1993
Creator: unknown
Object Type: Report
System: The UNT Digital Library
An automatic contact algorithm in DYNA3D for impact problems (open access)

An automatic contact algorithm in DYNA3D for impact problems

This paper presents a new approach for the automatic definition and treatment of mechanical contact in explicit nonlinear finite element analysis. Automatic contact offers the benefits of significantly reduced model construction time and fewer opportunities for user error, but faces significant challenges in reliability and computational costs. Key aspects of the proposed new method include automatic identification of adjacent and opposite surfaces in the global search phase, and the use of a well-defined surface normal which allows a consistent treatment of shell intersection and corner contact conditions without a ad-hoc rules. The paper concludes with three examples which illustrate the performance of the newly proposed algorithm in the public DYNA3D code.
Date: July 23, 1993
Creator: Whirley, R. G. & Engelmann, B. E.
Object Type: Article
System: The UNT Digital Library
Bench scale testing of micronized magnetite beneficiation. Quarterly technical progress report No. 1, April--June 1993 (open access)

Bench scale testing of micronized magnetite beneficiation. Quarterly technical progress report No. 1, April--June 1993

This project is aimed at development of a process that, by using ultra fine magnetite suspension, would expand the application of heavy media separation technology to processing fine, {minus}28 mesh coals. These coal fines, produced during coal mining and crushing, are separated in the conventional coal preparation plant and generally impounded in a tailings pond. Development of an economic process for processing these fines into marketable product will expand the utilization of coal for power production in an environmentally acceptable and economically viable way. This process has been successfully researched at PETC but has not been studied on a continuous bench-scale unit, which is a necessary step towards commercial development of this promising technology. The goal of the program is to investigate the technology in a continuous circuit at a reasonable scale to provide a design basis for larger plants and a commercial feasibility data. The project is divided into eight tasks which include design, construction, operation and testing, sample analysis, evaluation, and decommissioning. Coal will be received from three different mines and processed through the bench scale{backslash}e plant. Testing has been split into three phases: (1) Component Testing which will examine each of the major components independently, optimize, and …
Date: July 23, 1993
Creator: Anast, K.
Object Type: Report
System: The UNT Digital Library
Biomass energy: State of the technology present obstacles and future potential (open access)

Biomass energy: State of the technology present obstacles and future potential

The prevailing image of wood and waste burning as dirty and environmentally harmful is no longer valid. The use of biomass combustion for energy can solve many of our nation`s problems. Wood and other biomass residues that are now causing expensive disposal problems can be burned as cleanly and efficiently as natural gas, and at a fraction of the cost. New breakthroughs in integrated waste-to-energy systems, from fuel handling, combustion technology and control systems to heat transfer and power generation, have dramatically improved system costs, efficiencies, cleanliness of emissions, maintenance-free operation, and end-use applications. Increasing costs for fossil fuels and for waste disposal strict environmental regulations and changing political priorities have changed the economics and rules of the energy game. This report will describe the new rules, new playing fields and key players, in the hope that those who make our nation`s energy policy and those who play in the energy field will take biomass seriously and promote its use.
Date: June 23, 1993
Creator: Dobson, L.
Object Type: Report
System: The UNT Digital Library
Bunched Beam Longitudinal Instability: Coherent Dipole Motion (open access)

Bunched Beam Longitudinal Instability: Coherent Dipole Motion

In this paper, the authors present a new formulation for the longitudinal coherent dipole motion, where a quadrature response of the environmental impedance is shown to be the effective longitudinal impedance for the beam instability. The Robinson-Pedersen formulation for the longitudinal dipole motion is also presented, the difference of the two approaches is discussed in the comparison. The results by using the Sacherer integral equation for the coherent dipole motion can generate the same results as by using the other two approaches, except for a scaling difference. The formulation is further generalized to the rigid bunch motion using signal analysis method, where a form factor shows up naturally. Finally, the formulation is applied to solve the coupled bunch instabilities. Examples of the AGS Booster and the AGS coupled bunch instabilities are used to illustrate the applications of the formulation.
Date: April 23, 1993
Creator: Zhang, S. Y. & Weng, W. T.
Object Type: Report
System: The UNT Digital Library
Bunched beam longitudinal instability: Coherent dipole motion (open access)

Bunched beam longitudinal instability: Coherent dipole motion

In this paper, the authors present a new formulation for the longitudinal coherent dipole motion, where a quadrature response of the environmental impedance is shown to be the effective longitudinal impedance for the beam instability. The Robinson-Pedersen formulation for the longitudinal dipole motion is also presented, the difference of the two approaches is discussed in the comparison. The results by using the Sacherer integral equation for the coherent dipole motion can generate the same results as by using the other two approaches, except for a scaling difference. The formulation is further generalized to the rigid bunch motion using signal analysis method, where a form factor shows up naturally. Finally, the formulation is applied to solve the coupled bunch instabilities. Examples of the AGS Booster and the AGS coupled bunch instabilities are used to illustrate the applications of the formulation.
Date: April 23, 1993
Creator: Zhang, S. Y. & Weng, W. T.
Object Type: Report
System: The UNT Digital Library
Calorimeter based detectors for high energy hadron colliders (open access)

Calorimeter based detectors for high energy hadron colliders

The work was directed in two complementary directions, the D0 experiment at Fermilab, and the GEM detector for the SSC. Efforts have been towards the data taking and analysis with the newly commissioned D0 detector at Fermilab in the [bar p]p Collider run that started in May 1992 and ended on June 1, 1993. We involved running and calibration of the calorimeter and tracking chambers, the second level trigger development, and various parts of the data analysis, as well as studies for the D0 upgrade planned in the second half of this decade. Another major accomplishment was the delivery'' of the Technical Design Report for the GEM SSC detector. Efforts to the overall detector and magnet design, design of the facilities, installation studies, muon system coordination, muon chamber design and tests, muon system simulation studies, and physics simulation studies. In this document we describe these activities separately.
Date: June 23, 1993
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Calorimeter based detectors for high energy hadron colliders. [Progress report] (open access)

Calorimeter based detectors for high energy hadron colliders. [Progress report]

The work was directed in two complementary directions, the D0 experiment at Fermilab, and the GEM detector for the SSC. Efforts have been towards the data taking and analysis with the newly commissioned D0 detector at Fermilab in the {bar p}p Collider run that started in May 1992 and ended on June 1, 1993. We involved running and calibration of the calorimeter and tracking chambers, the second level trigger development, and various parts of the data analysis, as well as studies for the D0 upgrade planned in the second half of this decade. Another major accomplishment was the ``delivery`` of the Technical Design Report for the GEM SSC detector. Efforts to the overall detector and magnet design, design of the facilities, installation studies, muon system coordination, muon chamber design and tests, muon system simulation studies, and physics simulation studies. In this document we describe these activities separately.
Date: June 23, 1993
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Catalyst and process development for synthesis gas conversion to isobutylene. Quarterly report, July 1, 1993--September 30, 1993 (open access)

Catalyst and process development for synthesis gas conversion to isobutylene. Quarterly report, July 1, 1993--September 30, 1993

Trickle bed reactor experiments using precipitated and commercial zirconia resulted in the production of more C{sub 2}-C{sub 3} hydrocarbons than the fixed bed gas phase reactor when using a hydrogen to CO ratio of 1. Because of problems associated with solvent cracking the reactor temperature for the trickle bed was limited to 400{degrees}C, whereas temperatures up to 450{degrees}C had been used for the fixed bed reactors. Co-feeding H{sub 2}S with the synthesis gas resulted in reduction of C{sub 1} to C{sub 3} production rates, an increase in C{sub 5} production and an increase in the production of 3-methyl-l-butene. Zirconia prepared with Ce resulted in a highly active and selective catalyst with isobutylene production rates of 4 to 8.5 kg/(m{sup 3} cat. h) for CO conversions of 15 to 34%. Kinetic models necessary for reactor design are first order for CO and one half order for hydrogen, indicating the dissociation of hydrogen on the catalyst surface. Carbon dioxide was found to be the most abundant specie on the surface of the catalyst and retards the rate of reaction. A modification of the Anderson Schultz Flory distribution resulted in an empirical procedure for estimating product distributions.
Date: November 23, 1993
Creator: Anthony, R. G. & Akgerman, A.
Object Type: Report
System: The UNT Digital Library
Colorado School of Mines low energy nuclear physics project. Final technical progress report (open access)

Colorado School of Mines low energy nuclear physics project. Final technical progress report

This report summarizes the accomplishments of the project ``Studies of nuclear reactions at very low energies``. This project was undertaken in 1987 and completed in 1993. All but one of the major objectives of this study have been accomplished. Specifically the authors have completed their investigation of the (p,{gamma}) on light nuclei, a study of the Oppenheimer-Phillips effect, a measurements of the astrophysically interesting reaction D({alpha},{gamma}){sup 6}Li at low energies and an extension of the reaction D(d,{gamma}){sup 4}He to lower energies than previously observed. Preliminary investigation of te reaction {sup 7}Li({sup 3}He,p){sup 9}Be was begun and is continuing under a separate DOE grant. In addition to these tasks, they have completed some very interesting projects which were not included in the original proposal. These include a study of the (d,{gamma}) reactions on {sup 6}Li, {sup 7}Li and {sup 10}B and an investigation of the possibility of observing terrestrial antineutrinos from the beta decay chains of U and Th as a diagnostic of terrestrial heat flow.
Date: November 23, 1993
Creator: Cecil, F. E.
Object Type: Report
System: The UNT Digital Library
[Computer Science and Telecommunications Board activities] (open access)

[Computer Science and Telecommunications Board activities]

The board considers technical and policy issues pertaining to computer science, telecommunications, and associated technologies. Functions include providing a base of expertise for these fields in NRC, monitoring and promoting health of these fields, initiating studies of these fields as critical resources and sources of national economic strength, responding to requests for advice, and fostering interaction among the technologies and the other pure and applied science and technology. This document describes its major accomplishments, current programs, other sponsored activities, cooperative ventures, and plans and prospects.
Date: February 23, 1993
Creator: Blumenthal, M. S.
Object Type: Report
System: The UNT Digital Library
[Computer Science and Telecommunications Board activities] (open access)

[Computer Science and Telecommunications Board activities]

The board considers technical and policy issues pertaining to computer science, telecommunications, and associated technologies. Functions include providing a base of expertise for these fields in NRC, monitoring and promoting health of these fields, initiating studies of these fields as critical resources and sources of national economic strength, responding to requests for advice, and fostering interaction among the technologies and the other pure and applied science and technology. This document describes its major accomplishments, current programs, other sponsored activities, cooperative ventures, and plans and prospects.
Date: February 23, 1993
Creator: Blumenthal, M. S.
Object Type: Report
System: The UNT Digital Library
CP violation outside the standard model phenomenology for pedestrians (open access)

CP violation outside the standard model phenomenology for pedestrians

So far the only experimental evidence for CP violation is the 1964 discovery of K{sub L}{yields}2{pi} where the two mass eigenstates produced by neutral meson mixing both decay into the same CP eigenstate. This result is described by two parameters {epsilon} and {epsilon}{prime}. Today {epsilon} {approx} its 1964 value, {epsilon}{prime} data are still inconclusive and there is no new evidence for CP violation. One might expect to observe similar phenomena in other systems and also direct CP violation as charge asymmetries between decays of charge conjugate hadrons H{sup {+-}} {yields} f{sup {+-}}. Why is it so hard to find CP violation? How can B Physics help? Does CP lead beyond the standard model? The author presents a pedestrian symmetry approach which exhibits the difficulties and future possibilities of these two types of CP-violation experiments, neutral meson mixing and direct charge asymmetry: what may work, what doesn`t work and why.
Date: September 23, 1993
Creator: Lipkin, H. J.
Object Type: Article
System: The UNT Digital Library
Development of biological coal gasification (MicGAS process) (open access)

Development of biological coal gasification (MicGAS process)

Effect of 5% and 10% coal solids loadings was studied in two types of bench scale bioreactors and in chemostat cultures. The bench scale reactors used were rotating biological contactor (RBC) and upflow bioreactors. In RBC, Texas lignite was loaded at 0% and 5% (w/v), while in the upflow and chemostat reactors at 0%, 5% and 10%. Methane, total gas production, soluble carbon and volatile fatty acid production (VFA), as well as microbial growth (measured as cell protein) were monitored. Gas analysis of the headspace from the above mentioned reactors showed higher CO[sub 2] production in experiments with 5% and 10% coal solids (for example, Figure 1). This indicates that acetate degraded into CO[sub 2] but there was not enough hydrogen to carry out the reaction to convert CO[sub 2] to CH[sub 4]. These data obtained confirmed our previous results from laboratory scale reactors, that at coal solids loadings higher than 1%, methane production does not enhance significantly. This phenomena could be due to the production of higher quantities of inhibitory compounds or depletion of factors necessary for methanogenesis.
Date: January 23, 1993
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Development of biological coal gasification (MicGAS process). Tenth Quarterly report (open access)

Development of biological coal gasification (MicGAS process). Tenth Quarterly report

Effect of 5% and 10% coal solids loadings was studied in two types of bench scale bioreactors and in chemostat cultures. The bench scale reactors used were rotating biological contactor (RBC) and upflow bioreactors. In RBC, Texas lignite was loaded at 0% and 5% (w/v), while in the upflow and chemostat reactors at 0%, 5% and 10%. Methane, total gas production, soluble carbon and volatile fatty acid production (VFA), as well as microbial growth (measured as cell protein) were monitored. Gas analysis of the headspace from the above mentioned reactors showed higher CO{sub 2} production in experiments with 5% and 10% coal solids (for example, Figure 1). This indicates that acetate degraded into CO{sub 2} but there was not enough hydrogen to carry out the reaction to convert CO{sub 2} to CH{sub 4}. These data obtained confirmed our previous results from laboratory scale reactors, that at coal solids loadings higher than 1%, methane production does not enhance significantly. This phenomena could be due to the production of higher quantities of inhibitory compounds or depletion of factors necessary for methanogenesis.
Date: January 23, 1993
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Development of enhanced sulfur rejection processes (open access)

Development of enhanced sulfur rejection processes

Research at Virginia Tech led to two complementary concepts for improving the removal of inorganic sulfur from much of the Eastern US coals. One controls the surface properties of coal pyrite (FeS[sub 2]) by electrochemical-.potential control, referred to as the Electrochemically Enhanced Sulfur Rejection (EESR) Process: The second controls the flotation of middlings, i.e., particles composed of pyrite with coal inclusions by using polymeric reagents to react with pyrite and convert the middlings to hydrophilic particles, and is termed the Polymer Enhanced Sulfur Rejection (PESR) Process. These new concepts are based on recent research establishing the two main reasons why flotation fails to remove more than about 50% of the pyritic sulfur from coal: superficial oxidization of liberated pyrite to form polysulfide oxidation products so that a part of the liberated pyrite floats with the coal; and hydrophobic coal inclusions in the middlings dominating their flotation so that the middlings also float with the coal. These new pyritic-sulfur rejection processes do not require significant modifications of existing coal preparation facilities, enhancing their adoptability by the coal industry. It is believed that they can be used simultaneously to achieve both free pyrite and locked pyrite rejection.
Date: March 23, 1993
Creator: Yoon, R. H.; Luttrell, G.; Adel, G. & Richardson, P. E.
Object Type: Report
System: The UNT Digital Library
Development of enhanced sulfur rejection processes. First Quarterly technical progress report, October 1, 1992--December 31, 1992 (open access)

Development of enhanced sulfur rejection processes. First Quarterly technical progress report, October 1, 1992--December 31, 1992

Research at Virginia Tech led to two complementary concepts for improving the removal of inorganic sulfur from much of the Eastern US coals. One controls the surface properties of coal pyrite (FeS{sub 2}) by electrochemical-.potential control, referred to as the Electrochemically Enhanced Sulfur Rejection (EESR) Process: The second controls the flotation of middlings, i.e., particles composed of pyrite with coal inclusions by using polymeric reagents to react with pyrite and convert the middlings to hydrophilic particles, and is termed the Polymer Enhanced Sulfur Rejection (PESR) Process. These new concepts are based on recent research establishing the two main reasons why flotation fails to remove more than about 50% of the pyritic sulfur from coal: superficial oxidization of liberated pyrite to form polysulfide oxidation products so that a part of the liberated pyrite floats with the coal; and hydrophobic coal inclusions in the middlings dominating their flotation so that the middlings also float with the coal. These new pyritic-sulfur rejection processes do not require significant modifications of existing coal preparation facilities, enhancing their adoptability by the coal industry. It is believed that they can be used simultaneously to achieve both free pyrite and locked pyrite rejection.
Date: March 23, 1993
Creator: Yoon, R. H.; Luttrell, G.; Adel, G. & Richardson, P. E.
Object Type: Report
System: The UNT Digital Library
Device for calibrating a radiation detector system (open access)

Device for calibrating a radiation detector system

The present invention relates to a device for calibrating a radiation detector system that is used for measuring the radionuclide intake of those exposed to radioactive materials. In particular, the present invention relates to a device that simulates a human chest and lungs with a modicum of internal radiation for use in calibrating radiation detectors.
Date: September 23, 1993
Creator: McFee, M. C.; Kirkham, T. J. & Johnson, T. H.
Object Type: Patent
System: The UNT Digital Library
Digital control systems in nuclear power plants: Failure information, modeling concepts, and applications (open access)

Digital control systems in nuclear power plants: Failure information, modeling concepts, and applications

This report briefly describes some current applications of advanced computerized digital display and control systems at US commercial nuclear power plants and presents the results of a literature search that was made to gather information on the reliability of these systems. Both hardware and software reliability were addressed in this review. Only limited failure rate information was found, with the chemical process industry being the primary source of information on hardware failure rates and expert opinion the primary source for software failure rates. Safety-grade digital control systems are typically installed on a functional like-for-like basis, replacing older analog systems without substantially changing interactions with other plant systems. Future work includes performing a limited probabilistic risk assessment of a representative DCS to assess its risk significance.
Date: June 23, 1993
Creator: Galyean, W.J.
Object Type: Report
System: The UNT Digital Library
Digital control systems in nuclear power plants: Failure information, modeling concepts, and applications. Revision 1 (open access)

Digital control systems in nuclear power plants: Failure information, modeling concepts, and applications. Revision 1

This report briefly describes some current applications of advanced computerized digital display and control systems at US commercial nuclear power plants and presents the results of a literature search that was made to gather information on the reliability of these systems. Both hardware and software reliability were addressed in this review. Only limited failure rate information was found, with the chemical process industry being the primary source of information on hardware failure rates and expert opinion the primary source for software failure rates. Safety-grade digital control systems are typically installed on a functional like-for-like basis, replacing older analog systems without substantially changing interactions with other plant systems. Future work includes performing a limited probabilistic risk assessment of a representative DCS to assess its risk significance.
Date: June 23, 1993
Creator: Galyean, W. J.
Object Type: Report
System: The UNT Digital Library
DSP accelerator for the wavelet compression/decompression of high- resolution images (open access)

DSP accelerator for the wavelet compression/decompression of high- resolution images

A Texas Instruments (TI) TMS320C30-based S-Bus digital signal processing (DSP) module was used to accelerate a wavelet-based compression and decompression algorithm applied to high-resolution fingerprint images. The law enforcement community, together with the National Institute of Standards and Technology (NISI), is adopting a standard based on the wavelet transform for the compression, transmission, and decompression of scanned fingerprint images. A two-dimensional wavelet transform of the input image is computed. Then spatial/frequency regions are automatically analyzed for information content and quantized for subsequent Huffman encoding. Compression ratios range from 10:1 to 30:1 while maintaining the level of image quality necessary for identification. Several prototype systems were developed using SUN SPARCstation 2 with a 1280 {times} 1024 8-bit display, 64-Mbyte random access memory (RAM), Tiber distributed data interface (FDDI), and Spirit-30 S-Bus DSP-accelerators from Sonitech. The final implementation of the DSP-accelerated algorithm performed the compression or decompression operation in 3.5 s per print. Further increases in system throughput were obtained by adding several DSP accelerators operating in parallel.
Date: July 23, 1993
Creator: Hunt, M. A.; Gleason, S. S. & Jatko, W. B.
Object Type: Article
System: The UNT Digital Library
Employment Impacts of Geothermal Electric Projects (open access)

Employment Impacts of Geothermal Electric Projects

Table 1 summarizes the number of jobs associated with the development and operation of a 50 MW geothermal dual flash power system. The values shown are person years (PY) of employment for the 50 MW system. About 1500 person years (PY) of labor are incorporated in the manufacture and installation of capital components of the system. Of these, about 300 PY are local to the area of the geothermal system, and about 1200 are dispersed elsewhere in the U.S. or other countries. About 71 PY of labor per year are required for the operation of the system. Of those, about 39 PY are local to the plant, and about 32 are dispersed. The total person years of labor over the entire life cycle of such a system, assuming a 30-year operational life, is on the order of 3630 person years. These include jobs during the 5 to 10 years of exploration and construction activities prior to plant start up. Of these jobs, about 1470 PY are local to the system, and about 21 60 are dispersed elsewhere.
Date: May 23, 1993
Creator: Entingh, Daniel J.
Object Type: Report
System: The UNT Digital Library
Engineering development of advanced coal-fired low-emission boiler systems. Quarterly technical progress report, April 1--June 30, 1993 (open access)

Engineering development of advanced coal-fired low-emission boiler systems. Quarterly technical progress report, April 1--June 30, 1993

Preliminary sketches of the furnace setting with dimensions and other appropriate data was distributed to appropriate boiler design groups. The purpose of this work was to define and/or establish unique mechanical and support requirements and furnace water circulation requirements. A preliminary convection pass arrangement and heating surface requirements were established. Initial computer runs indicate, as expected, that establishing even a preliminary arrangement to meet steam duty requirements was going to be a challenge. This due to slightly lower furnace exit gas temperatures (result of NO{sub x} control conditions) and higher final steam temperatures (results increasing plant efficiency) than typical of conventional design. Work on the furnace and convection pass design for the base preliminary unit was completed only to the extent necessary to identify design deficiencies, prepare an arrangement drawing and determine budgetary cost. Engineering work has been completed to the extent planned in this subtask for the base preliminary unit, Advanced Overfire Air, including preliminary designs for the furnace, convection pass, pulverizers, airheaters, flues and ducts, preliminary general arrangement drawings, and budgetary cost estimates. Work is nearly complete on design of the LEBS unit control system based on control methods and philosophy established in the NO{sub x} Control Subsystems. …
Date: July 23, 1993
Creator: unknown
Object Type: Report
System: The UNT Digital Library