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 …

A three-dimensional spectral radiation transport model has been developed for assessing the impact of burning deeply cleaned coals on heat absorption patterns in pulverized coal (PC) furnaces. Spectroscopic data are used for calculating the absorption coefficients of participating gases. Mie theory is invoked for determining the extinction and scattering efficiencies of combustion particulates. The optical constants of char, ash and soot are obtained from dispersion relations derived from reflectivity, transmissivity and extinction measurements. 8 refs., 2 figs., 3 tabs.

This is a progress report for the past one year of research (year 3 of 5-year project) under the project titled CSDP: Seismology of Continental Thermal Regime'', in which we proposed to develop seismological interpretation theory and methods applicable to complex structures encountered in continental geothermal areas and apply them to several candidate sites for the Continental Scientific Drilling Project. The past year has been extremely productive especially in the area of interpretation theory, including the following two major break-throughs. One is the derivation of an integral equation for time-dependent power spectra, which unified all the existing theories on seismic scattering (including the radiative transfer theory for total energy and single and multiple scattering theories based on the ray approach) and offers more complete and economical solutions to the problems of seismic scattering and attenuation. The other is the new formula for synthetic seismograms for layered media with irregular interfaces, combining the T-matrix method for an arbitrary shaped inclusion and the method of global generalized reflection/transmission coefficients for layered media. Both breakthroughs will enable us to deal with seismic observations in complex earth structures more efficiently and accurately. In the area of experimental studies, we discovered seismic guided waves trapped …

We expand upon our previous Monte-Carlo-type study of 3-family mass matrices which lead to the experimentally-determined KM matrix and satisfy the constraints imposed by B{sub d}--{bar B}{sub d} mixing, {vert bar}V{sub ub}/V{sub cb}{vert bar}, B{sub K} and CP violation. Scatter distributions in {vert bar}V{sub ub}V{sub cb}{vert bar}, {epsilon}{prime}/{epsilon} and x{sub s} vs m{sub t} are presented for the standard minimal Higgs structure as well as top quark mass histograms for the minimal and 2-doublet Higgs models. A top quark mass in the range of 100--200 GeV is strongly favored with all the constraints imposed, but if the lower bound on the CP-violating J-value is completely relaxed, a secondary probability peaking occurs in the mass histograms which lies above 220 GeV in the minimal Higgs model. 19 refs., 5 figs.

In order to evaluate the effectiveness of Section 11, Division 1, Rules for Inservice Inspection of Nuclear Power Plant Components,'' of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code examinations, 26 inservice inspection (ISI) summary reports from 24 facilities were reviewed. It was found that these ASME Code examinations and tests are instrumental in revealing indications and defects in welds and plant components. In addition, this study uncovered that fact that some of the Section 11 requirements are apparently not clear and are misunderstood by some of the facilities. Also, the need for more stringent requirements was evaluated and some Code changes are recommended.

In order to evaluate the effectiveness of Section 11, Division 1, ``Rules for Inservice Inspection of Nuclear Power Plant Components,`` of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code examinations, 26 inservice inspection (ISI) summary reports from 24 facilities were reviewed. It was found that these ASME Code examinations and tests are instrumental in revealing indications and defects in welds and plant components. In addition, this study uncovered that fact that some of the Section 11 requirements are apparently not clear and are misunderstood by some of the facilities. Also, the need for more stringent requirements was evaluated and some Code changes are recommended.

Patent for Settling Basin-Separating Devices. This device improves the issue of unwanted discharge shown in prior devices

Report describing the methodology used to sample and analyze sediment at Ocean City, Maryland as part of a beach nourishment project. During the project, sediment was moved from borrow sites to construct parts of the beach area; both the borrow sites and native beach were tested.

We have developed new absorption-based chemical indicators for detecting chloroform (CHCl{sub 3}) and trichloroethylene (TCE). These indicators were used to make very sensitive optical chemical sensors (optrodes) for each of these two contaminants. Concentrations below 10 ppb can be accurately measured using these sensors. Furthermore, they are selective and do not response to similar contaminants commonly found with TCE and CHCl{sub 3} in contaminated groundwater. In addition, the sensor response is linearly proportional to the chemical concentration. In this report, we describe the details of this optrode and the putative reaction sequences of the indicator chemistries with CHCl{sub 3} and TCE and present an analysis of the spectral data obtained from the reaction products. A key part of the development of this optrode was designing a simple readout device. The readout is a dual-channel fiber-optic fluorimeter modified to measure transmission or absorption of light. The system is controlled by a lap-top microcomputer and is fully field portable. In addition to describing the final absorption optrode, details of the chemical indicator reactions are presented for both absorption- (colorimetric) and fluorescence-based optrodes. Finally, we report on the syntheses of several compounds used to evaluate the indicator chemical reactions that led to the …

This thesis presents the results of some of the author's work in the High Energy Physics Group at Brown University, work done within the framework of the D0 collaboration at the Fermilab National particle accelerator. To allow a broader audience an easier understanding of the experimental data presented, a brief review of the relevant areas of Particle Physics precedes the description of the experimental setup and results. Monte Carlo simulations of Z boson production at the D0 experiment were made to allow for precise predictions of expected data at the accelerator when construction reaches completion. The specific work that was executed is presented in detail, from the point of view of experimental high energy research, followed by comments on the results obtained and on possible future directions. 4 refs., 15 figs.

Energy-related greenhouse gas (GHG) emissions arise from a number of fossil fuels, processes and equipment types throughout the full cycle from primary fuel production to end-use. Many technology alternatives are available for reducing emissions based on efficiency improvements, fuel switching to low-emission fuels, GHG removal, and changes in end-use demand. To conduct systematic analysis of how new technologies can be used to alter current emission levels, a conceptual framework helps develop a comprehensive picture of both the primary and secondary impacts of a new technology. This paper describes a broad generic fuel cycle framework which is useful for this purpose. The framework is used for cataloging emission source technologies and for evaluating technology solutions to reduce GHG emissions. It is important to evaluate fuel mix tradeoffs when investigating various technology strategies for emission reductions. For instance, while substituting natural gas for coal or oil in end-use applications to reduce CO{sub 2} emissions, natural gas emissions of methane in the production phase of the fuel cycle may increase. Example uses of the framework are given.

A brief summary is presented of results pertinent to quark spectroscopy derived from high statistics data on K{sup {minus}}p interactions obtained with the LASS spectrometer at SLAC. The present status of strange meson spectroscopy is briefly reviewed, and the impact of the proposed KAON Factory on the future of the subject considered. 36 refs., 24 figs.

The Physics Section vacuum deposition system is available for several types of thin film techniques. This vacuum evaporation system operates in the high vacuum range. The evaporation source is a resistive heating element, either a boat or a filament design. Coating is then line of sight from the source. Substrates to be coated can have a maximum diameter of 17 inches. At this time the variations in the thickness of the coatings can be controlled, by monitor, to within about 100 angstroms. The system diagrams follow the Operation Procedures and the Sample Coating Procedures provided in this document. 3 figs.

Superdeformation was first observed in the mass-190 region in {sup 191}Hg. Since then, SD bands have been found in {sup 190-194}Hg nuclei. Here we report the discovery of two such bands in {sup 194}Tl which are the first SD bands fond in this mass region that are not in Hg nuclei. Subsequently, bands have been found in two Pb nuclei. 5 refs., 1 fig.

An analysis of the proton rapidity distribution in central {sup 16}O+Au collisions at 60 GeV/n measured in the NA35 streamer chamber detector at the CERN SPS is presented. The charge excess of positive particles over negative particles was measured. The rapidity distribution of the charge excess which can be associated with the primordial protons in the collision is studied in terms of the nuclear stopping power and is compared to the predictions of various models. 7 refs., 2 figs.

No present light water reactor accident analysis code employs both high state of the art neutronics and thermal-hydraulics computational algorithms. Adding a modern three-dimensional neutron kinetics model to the present TRAC-PFI/MOD2 code would create a fully up to date pressurized water reactor accident evaluation code. After reviewing several options, it was decided that the Nodal Expansion Method would best provide the basis for this multidimensional transient neutronic analysis capability. Steady-state and transient versions of the Nodal Expansion Method were coded in both three-dimensional Cartesian and cylindrical geometries. In stand-alone form this method of solving the few group neutron diffusion equations was shown to yield efficient and accurate results for a variety of steady-state and transient benchmark problems. The Nodal Expansion Method was then incorporated into TRAC-PFl/MOD2. The combined NEM/TRAC code results agreed well with the EPRI-ARROTTA core-only transient analysis code when modelling a severe PWR control rod ejection accident.

In the Stanford Linear Collider the beam leaves a damping ring and then enters the Ring-to-Linac (RTL) transfer line. In the RTL it is compressed in length by a factor of 10 by means of an rf section, with which a longitudinally correlated energy variation is induced in the beam, and a following beam line which has non-zero momentum compaction. The compressed beam then enters the linac proper. In this paper we describe three measurements of longitudinal properties of the beam in the SLC linac. We present measurements of single bunch beam loading, of the energy spectrum at the end of the linac, and of the linac bunch length. Since the results of all three measurements depend on the beam's longitudinal charge distribution in the linac they, in turn, also depend on the bunch lengthening that occurs in the damping rings, as well as on the behavior of the compressor. The results of the first two measurements, in addition, depend critically on the strength of the longitudinal wakefields in the linac. The results of these three measurements are compared with simulations. For these calculations, at any given current, the potential well distortion in the damping ring is first computed. The …

The US-Japan Workshop on Field-Reversed Configurations with Steady-State High-Temperature Fusion Plasma and the 11th US-Japan Workshop on Compact Toroids were held at Los Alamos National Laboratory, Los Alamos, New Mexico on November 7--9, 1989. These proceedings contain the papers presented at the workshops as submitted by the authors. These papers have been indexed separately.

The production of top at the Fermilab Tevatron D0 detector was investigated using full Monte Carlo and event reconstruction packages. In total, 480 events were generated for m{sub T} = 150 GeV/c{sup 2} in the specific t({bar t}) {yields} b({bar b}) + W{sup {plus minus}}, with at least one W decaying to leptons. These events were then analyzed in an attempt to find characteristic signals for top production at D0. 21 figs.

The purpose of this contract was to assemble and demonstrate in the laboratory a Faraday rotation system for measurement of electron density and conductivity, with the intent to produce a system suitable for diagnostic support of the development of pulsed, space-based magnetohydrodynamic (MHD) power systems. Two system configurations were tested: (1) a rotating polarizer and (2) a beam splitting polarizer. Due to the short path length plasma produced in the laboratory flame, the long wavelength 496 {mu}m methyl fluoride laser line was used and only the more sensitive rotating polarizer configuration was used for the demonstration experiments. Electron number densities from 2 {times} 10{sup 19} to 9 {times} 10{sup 19} were measured with good agreement to statistical equilibrium (Saha) calculations using emission absorption-measured flame temperatures and neutral seed atom number seed atom nuclear densities. The electron collision frequencies were measured by transmission measurements. Combining these two measurements gave measured electron conductivities of between 4 and 12 mohs/m. These results compared reasonably well with those found with an electron collision frequency model combined with chemical equilibrium calculations and the emission absorption measurements. Ellipticity measurements of electron collision frequency were not possible due to the short path length of the laboratory plasma. …

Gamma-ray damage to tank walls is typically more severe in D{sub 2}O than in H{sub 2}O moderated lattices because of the much higher ratios of slow-to-fast neutron flux. To estimate this effect it was first necessary to develop energy dependent gamma-ray displacement cross sections for iron. These, along with coupled neutron-gamma-ray transport computations, provided a measure of displacement damage from this source in SRS reactor tank walls. Gamma-ray displacements originating from high energy gammas from neutron capture in and near the tank wall exceeded those from gamma rays created in the reactor core. The displacements from the combined gamma sources ranged from 13% to 16% of that due to iron atom recoil following neutron capture. 8 refs., 2 figs., 2 tabs.

In 1988 and 1989, 150 manufactured homes were built to comply with Super Good Cents (SGC) specifications adapted from the existing specifications for site-built homes under the Residential Construction Demonstration Project (RCDP). Engineering calculations and computer simulations were used to estimate the effects of the SGC specifications on the thermal performance of the homes. These results were compared with consumer costs to establish the cost-effectiveness of individual measures. Heat loss U-factors for windows, walls, floors and ceilings were established using the standard ASHRAE parallel heat flow method. Adjustments resulted in higher U-factors for ceilings and floors than assumed at the time the homes were approved as meeting the SGC specifications. Except for those homes which included heat pumps, most of the homes did not meet the SGC compliance standards. Nonetheless these homes achieved substantial reductions in overall heat loss rate (UA) compared to UAs estimated for the same homes using the standard insulation packages provided by the manufacturers in the absence of the RCDP program. Homes with conventional electric furnaces showed a 35% reduction in total UA while homes with heat pumps had a 25% reduction. A regression analysis showed no significant relationship between climate zone, manufacturer and UA. A …

We report on the performance of a prototype of a super-ferric micro-undulator. The micro-undulator consists of a continuous winding of niobium-titanium wire wound on a low carbon steel yoke. It is about 3 periods long with a period of 8.8 mm and a gap of 4.4 mm. The undulator achieves the a peak magnetic field on axis of over 0.5 Tesla. Asymmetry of the field pattern due to a dipole component was identified, analyzed and a correction has been applied to the undulator ends to produce a symmetric field distribution. Within the precision of the measurement the field pattern produced by the super-ferric undulator needed no correction. 4 refs., 7 figs.

We describe a large (78-cm) diameter liquid-helium-cooled black-body absolute reference cold load for the calibration of microwave radiometers. The load provides an absolute calibration near the liquid helium (LHe) boiling point, accurate to better than 30 mK for wavelengths from 2.5 to 25 cm (12-1.2 GHz). The emission (from non-LHe temperature parts of the cold load) and reflection are small and well determined. Total corrections to the LHe boiling point temperature are {le} 50 mK over the operating range. This cold load has been used at several wavelengths at the South Pole and at the White Mountain Research Station. In operation, the average LHe loss rate was {le} 4.4 l/hr. Design considerations, radiometric and thermal performance and operational aspects are discussed. A comparison with other LHe-cooled reference loads including the predecessor of this cold load is given.