Future microprocessor farms: Offline and online (open access)

Future microprocessor farms: Offline and online

Microprocessor farms have been successfully employed in high energy physics for both offline analysis and online triggers. As the experiments continue to grow in size, so do the demands for processing power. The preliminary indications are that the large collider experiments will require at least a million VAX-11/780 equivalents of processing power for online trigger decisions and offline event reconstruction. This paper examines the current technology trends and projects the processing power that may be expected with the current farm architectures. 3 refs., 6 figs.
Date: January 12, 1990
Creator: Areti, H.
Object Type: Report
System: The UNT Digital Library
Liquid Argon Maximm Convective Heat Flux vs. Liquid Depth (open access)

Liquid Argon Maximm Convective Heat Flux vs. Liquid Depth

In order to help answer questions about the magnitude of heat flux to the liquid argon in a liquid argon calorimeter which could cause boiling (bubbles), calculations estimating the heat flux which can be removed by free convection were made in February, 1988. These calculations are intended to be an estimate of the heat flux above which boiling would occur. No formal writeup was made of these calculations, although the graph dated 3 Feb 88 and revised (adding low-velocity forced convection lines) 19 Feb 88 was presented in several meetings and widely distributed. With this description of the calculations, copies of the original graph and calculations are being added to the D0 Engineering Note files. The liquid argon surface is in equilibrium with argon vapor at a pressure of 1.3 bar, so the surface is at 89.70 K. The liquid is entirely at this surface temperature throughout the bulk of the volume, except locally where it is warmed by a solid surface at a higher temperature than the bulk liquid. This surface temperature is taken to be the boiling temperature of argon at the pressure corresponding to 1.3 bar plus the liquid head; hence it is a function of depth …
Date: January 12, 1990
Creator: Peterson, T.
Object Type: Report
System: The UNT Digital Library
Mass storage for microprocessor farms (open access)

Mass storage for microprocessor farms

Experiments in high energy physics require high density and high speed mass storage. Mass storage is needed for data logging during the online data acquisition, data retrieval and storage during the event reconstruction and data manipulation during the physics analysis. This paper examines the storage and speed requirements at the first two stages of the experiments and suggests a possible starting point to deal with the problem. 3 refs., 3 figs.
Date: January 12, 1990
Creator: Areti, H.
Object Type: Report
System: The UNT Digital Library
Performance of a 500 watt Nd:GGG zigzag slab oscillator (open access)

Performance of a 500 watt Nd:GGG zigzag slab oscillator

Realization of practical multi-kilowatt Nd:garnet lasers will require the scale-up of crystal dimensions as well as more powerful pumping sources. A high average power zigzag slab crystal amplifier testing facility has been established at LLNL which employs two 100 kW{sub e} vortex stabilized arc lamps, cooled reflectors and a cooled, spectrally filtered, crystal slab mounting fixture. The operational characteristics of the first crystal laser to be tested in this setup, a Nd:GGG zigzag oscillator, are presented. A Nd:GGG crystal of dimensions 18 {times} 7 {times} 0.5 cm{sup 3}, doped at 2 {times} 10{sup 20} cm{sup {minus}3} Nd{sup 3+} atomic density, was pumped by up to 40 kW of filtered argon line emission. A small-signal single pass gain (losses excluded) of 1.09 was measured with a probe laser when the DC input to the lamps was 43 kW{sub e}. Our power supply was then modified to operate in a pulsed mode and provided one to three milliseconds pulses at 120 Hz. An average optical output power of 490 watts was obtained at a lamp input power of 93 kW{sub e} in an unoptimized resonator. The laser output power declined after a few tens of seconds since the slab tips were not …
Date: January 12, 1990
Creator: Zapata, L.; Manes, K. R.; Christie, D.; Davin, J.; Blink, J.; Penland, J. et al.
Object Type: Article
System: The UNT Digital Library
Texas Register, Volume 15, Number 4, Pages 145-239, January 12, 1990 (open access)

Texas Register, Volume 15, Number 4, Pages 145-239, January 12, 1990

A weekly publication, the Texas Register serves as the journal of state agency rulemaking for Texas. Information published in the Texas Register includes proposed, adopted, withdrawn and emergency rule actions, notices of state agency review of agency rules, governor's appointments, attorney general opinions, and miscellaneous documents such as requests for proposals. After adoption, these rulemaking actions are codified into the Texas Administrative Code.
Date: January 12, 1990
Creator: Texas. Secretary of State.
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
Wideband beam patterns from sparse arrays (open access)

Wideband beam patterns from sparse arrays

Transient radiated fields due to impulsively excited apertures and aperture response due to incident impulsive waves has been the subject of considerable research in acoustics over the last decade. This research is also of importance to wideband radar. Medical ultrasound steered phased arrays use transmitted pulses consisting of from 1 to 3 cycles of a damped sinusoid, which is similar to certain radar systems. As will be shown, planar arrays using ultra-wide band pulses may be formed with very sparsely spaced elements. This makes feasible very high resolution, economical, and relatively simple, steered beam phased arrays. The resolution may be increased simply by moving the array elements further apart. Grating lobes due to aliasing are not formed when the elements are sparsely spaced. In a very sparse wide band array, element spacing effects the form, or signal shape in time, rather than the peak amplitude of the sidelobe structure. The number of elements in the aperture determines the peak sidelobe level which, in theory, may be decreased without limit. 13 refs., 7 figs.
Date: January 12, 1990
Creator: Anderson, F. (Anderson (Forrest), Bernalillo, NM (USA)); Fullerton, L. (Time Domain Systems, Huntsville, AL (USA)); Christensen, W. & Kortegaard, B. (Los Alamos National Lab., NM (USA))
Object Type: Article
System: The UNT Digital Library
Nonlinear plasma and beam physics in plasma wake-fields (open access)

Nonlinear plasma and beam physics in plasma wake-fields

In experimental studies of the Plasma Wake-field Accelerator performed to date at the Argonne Advanced Accelerator Test Facility, significant nonlinearities in both plasma and beam behavior have been observed. The plasma waves driven in the wake of the intense driving beam in these experiments exhibit three-dimensional nonlinear behavior which has as yet no quantitative theoretical explanation. This nonlinearity is due in part to the self-pinching of the driving beam in the plasma, as the denser self-focused beam can excite larger amplitude plasma waves. The self-pinching is a process with interesting nonlinear aspects: the initial evolution of the beam envelope and the subsequent approach to Bennett equilibrium through phase mixing. 35 refs., 10 figs.
Date: February 12, 1990
Creator: Rosenzweig, J.B.
Object Type: Article
System: The UNT Digital Library
Texas Attorney General Opinion: JM-1142 (open access)

Texas Attorney General Opinion: JM-1142

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;Types of retirement plans that appraisal districts may offer their employees(RQ-1778).
Date: February 12, 1990
Creator: Texas. Attorney-General's Office.
Object Type: Text
System: The Portal to Texas History
Direct conversion of methane to C sub 2 's and liquid fuels (open access)

Direct conversion of methane to C sub 2 's and liquid fuels

The objectives of the project are to discover and evaluate novel catalytic systems for the conversion of methane or by-product light hydrocarbon gases either indirectly (through intermediate light gases rich in C{sub 2}'s) or directly to liquid hydrocarbon fuels, and to evaluate, from an engineering perspective, different conceptualized schemes. The approach is to carry out catalyst testing on several specific classes of potential catalysts for the conversion of methane selectively to C{sub 2} products. The behavior of alkaline earth/metal oxide/halide catalysts containing strontium was found to be different from the behavior of catalysts containing barium. Two approaches were pursued to avoid the heterogeneous/homogeneous mechanism in order to achieve higher C{sub 2} selectivity/methane conversion combinations. One approach was to eliminate or minimize the typical gas phase combustion chemistry and make more of the reaction occur on the surface of the catalyst by using silver. Another approach was to change the gas phase chemistry to depart from the typical combustion reaction network by using vapor-phase catalysts. The layered perovskite K{sub 2}La{sub 2}Ti{sub 3}O{sub 10} was further studied. Modifications of process and catalyst variables for LaCaMnCoO{sub 6} catalysts resulted in catalysts with superior performance. Results obtained with a literature catalyst Na{sub 2}CO{sub 3}/Pr{sub …
Date: March 12, 1990
Creator: Warren, B. K.; Campbell, K. D.; Matherne, J. L. & Kinkade, N. E.
Object Type: Report
System: The UNT Digital Library
Assuring both quality and creativity in basic research (open access)

Assuring both quality and creativity in basic research

How does one assure that both quality and creativity are obtained in basic research environments QA theoreticians have attempted to develop workable definitions of quality, but in more reflective moments, these definitions often fail to capture the deeper essence of the idea of quality.'' This paper asserts that creativity (as a product of the human mind) is a concrete interface between perfunctory definitions of quality (conformance to specifications) and more philosophical speculations about the nature of quality- related ultimates'' like elegance or beauty. In addition, we describe the distinction between creative ideas and creative acts and highlight one of the major inhibitors of creativity, fear. Finally we show that highly creative people often have an irreverent attitude toward boundaries and established authority, and discuss how one can allow for this when designing a QA program in a basic research environment.
Date: April 12, 1990
Creator: Bodnarczuk, Mark
Object Type: Article
System: The UNT Digital Library
Is There Hope for Fusion (open access)

Is There Hope for Fusion

From the outset in the 1950's, fusion research has been motivated by environmental concerns as well as long-term fuel supply issues. Compared to fossil fuels both fusion and fission would produce essentially zero emissions to the atmosphere. Compared to fission, fusion reactors should offer high demonstrability of public protection from accidents and a substantial amelioration of the radioactive waste problem. Fusion still requires lengthy development, the earliest commercial deployment being likely to occur around 2025--2050. However, steady scientific progress is being made and there is a wide consensus that it is time to plan large-scale engineering development. A major international effort, called the International Thermonuclear Experimental Reactor (ITER), is being carried out under IAEA auspices to design the world's first fusion engineering test reactor, which could be constructed in the 1990's. 4 figs., 3 tabs.
Date: April 12, 1990
Creator: Fowler, T. K.
Object Type: Article
System: The UNT Digital Library
Texas Attorney General Opinion: JM-1154 (open access)

Texas Attorney General Opinion: JM-1154

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: Waiver of insurance deductible under section 27.02 of the Business and Commerce Code (RQ-1843)
Date: April 12, 1990
Creator: Texas. Attorney-General's Office.
Object Type: Text
System: The Portal to Texas History
Texas Attorney General Opinion: LO90-16 (open access)

Texas Attorney General Opinion: LO90-16

Letter opinion 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: Questions regarding the fire codes for unincorporated areas in counties with populations over 250,000.
Date: April 12, 1990
Creator: Texas. Attorney-General's Office.
Object Type: Text
System: The Portal to Texas History
Simulation of top quark production at D0 (open access)

Simulation of top quark production at D0

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.
Date: May 12, 1990
Creator: Barter, C.M.
Object Type: Report
System: The UNT Digital Library
Flashlamp pumping of Nd:glass disk amplifiers (open access)

Flashlamp pumping of Nd:glass disk amplifiers

We present experimental results and a model of Nd:glass disk amplifiers which are used in inertial confinement fusion research. We first review our previous measurements on pulsed xenon flashlamps. We then discuss out measurements on the enhancement of the Nd fluorescence decay rate in laser disks by amplified spontaneous emission. Using these data, we have constructed a model of flashlamp pumping which treats the transfer efficiency of pump light from the flashlamps to the disks as an empirical function. We have found a simple description of this cavity transfer function which provides an excellent fit to the amplifier results for various pump pulselengths. We discuss the concept of the pump area ratio for describing the flashlamp packing density and show that amplifier performance is optimized for values of this parameter near unity. We finally present results for both a single-segment and a multisegment disk amplifier. We have used these devices to investigate new amplifier designs for a large scale fusion driver. 11 refs., 13 figs.
Date: June 12, 1990
Creator: Powell, H. T.; Erlandson, A. C.; Jancaitis, K. S. & Murray, J. E.
Object Type: Article
System: The UNT Digital Library
High beta and second stability region transport and stability analysis (open access)

High beta and second stability region transport and stability analysis

This document summarizes progress made on the research of high beta and second region transport and stability. In the area second stability region studies we report on an investigation of the possibility of second region access in the center of TFTR supershots.'' The instabilities found may coincide with experimental observation. Significant progress has been made on the resistive stability properties of high beta poloidal supershot'' discharges. For these studies profiles were taken from the TRANSP transport analysis code which analyzes experimental data. Invoking flattening of the pressure profile on mode rational surfaces causes tearing modes to persist into the experimental range of interest. Further, the experimental observation of the modes seems to be consistent with the predictions of the MHD model. In addition, code development in several areas has proceeded.
Date: June 12, 1990
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Mechanistic studies of carbon monoxide reduction (open access)

Mechanistic studies of carbon monoxide reduction

The progress made during the current grant period (1 January 1988--1 April 1990) in three different areas of research is summarized. The research areas are: (1) oxidatively-induced double carbonylation reactions to form {alpha}-ketoacyl complexes and studies of the reactivity of the resulting compounds, (2) mechanistic studies of the carbonylation of nitroaromatics to form isocyanates, carbamates, and ureas, and (3) studies of the formation and reactivity of unusual metallacycles and alkylidene ligands supported on binuclear iron carbonyl fragments. 18 refs., 5 figs., 1 tab.
Date: June 12, 1990
Creator: Geoffroy, G.L.
Object Type: Report
System: The UNT Digital Library
Texas Register, Volume 15, Number 44, Pages 3377-3452, June 12, 1990 (open access)

Texas Register, Volume 15, Number 44, Pages 3377-3452, June 12, 1990

A weekly publication, the Texas Register serves as the journal of state agency rulemaking for Texas. Information published in the Texas Register includes proposed, adopted, withdrawn and emergency rule actions, notices of state agency review of agency rules, governor's appointments, attorney general opinions, and miscellaneous documents such as requests for proposals. After adoption, these rulemaking actions are codified into the Texas Administrative Code.
Date: June 12, 1990
Creator: Texas. Secretary of State.
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
CC Pressure Test (open access)

CC Pressure Test

The inner vessel heads including bypass and beam tubes had just been welded into place and dye penetrant checked. The vacuum heads were not on at this time but the vacuum shell was on covering the piping penetrating into the inner vessel. Signal boxes with all feed through boards, the instrumentation box, and high voltage boxes were all installed with their pump outs capped. All 1/4-inch instrumentation lines were terminated at their respective shutoff valves. All vacuum piping used for pumping down the inner vessel was isolated using o-ring sealed blind flanges. PV215A (VAT Series 12), the 4-inch VRC gate valve isolating the cyropump, and the rupture disk had to be removed and replaced with blind flanges before pressurizing due to their pressure limitations. Stresses in plates used as blind flanges were checked using Code calcualtions. Before the CC test, vacuum style blanks and clamps were hydrostatically pressure tested to 150% of the maximum test pressure, 60 psig. The Code inspector and Research Division Safety had all given their approval to the test pressure and procedure prior to filling the vessel with argon. The test was a major success. Based on the lack of any distinguishable pressure drop indicated on …
Date: July 12, 1990
Creator: Dixon, K.
Object Type: Report
System: The UNT Digital Library
Development and application of photosensitive device systems to studies of biological and organic materials (open access)

Development and application of photosensitive device systems to studies of biological and organic materials

This report discusses the following basic research accomplishments: new x-ray structure determination methods were developed and applied to biomembrane lipid phases; a novel mechanism for general anesthesia was proposed; the elastic properties of membranes were investigated, both theoretically and experimentally; the effects of high pressures on membranes were studied; neutron diffraction was used to probe mesophase structure; and novel lipid and surfactant systems are characterized. Also discussed are instrumentation accomplishments.
Date: July 12, 1990
Creator: Gruner, S. M. & Reynolds, G. T.
Object Type: Report
System: The UNT Digital Library
1990 Fischer Standard study (open access)

1990 Fischer Standard study

The purpose of this work is to develop a set of Titanium areal density standards for calibration and maintenance of the Fischer`s X-ray Fluorescence measurement system characterization curve program. The electron microprobe was calibrated for Titanium films on ceramic substrates using an existing set of laboratory standards (Quantity: 6 Range: 0.310 to 1.605). Fourteen source assemblies were measured and assigned values. These values are based on a mean calculation, of five separate readings, from best curve fit equations developed form the plot of the laboratory standards areal density (Source Measure) versus electron microprobe measurement (reading). The best fit equations were determined using the SAS General Linear Modeling (GLM) procedure. Four separate best fit equations were evaluated (Linear, Quadratic, Cubic and Exponential). Areal density values for the Fischer Standards appear here ordered by best fit equation based on maximum R{sup 2}.
Date: September 12, 1990
Creator: Roubik, G. J.
Object Type: Report
System: The UNT Digital Library
Energy sweep compensation of induction accelerators (open access)

Energy sweep compensation of induction accelerators

The ETA-II linear induction accelerator (LIA) is designed to drive a microwave free electron laser (FEL). Beam energy sweep must be limited to {plus minus}1% for 50 ns to limit beam corkscrew motion and ensure high power FEL output over the full duration of the beam flattop. To achieve this energy sweep requirement, we have implemented a pulse distribution system and are planning implementation of a tapered pulse forming line (PFL) in the pulse generators driving acceleration gaps. The pulse distribution system assures proper phasing of the high voltage pulse to the electron beam. Additionally, cell-to-cell coupling of beam induced transients is reduced. The tapered PFL compensates for accelerator cell and loading nonlinearities. Circuit simulations show good agreement with preliminary data and predict the required energy sweep requirement can be met.
Date: September 12, 1990
Creator: Sampayan, S. E.; Caporaso, G. J.; Chen, Y. J.; Decker, T. A. & Turner, W. C.
Object Type: Article
System: The UNT Digital Library
Laser-based flow cytometric analysis of genotoxicity of humans exposed to ionizing radiation during the Chernobyl accident (open access)

Laser-based flow cytometric analysis of genotoxicity of humans exposed to ionizing radiation during the Chernobyl accident

An analytical technique has been developed that allows laser-based flow cytometric measurement of the frequency of red blood cells that have lost allele-specific expression of a cell surface antigen due to genetic toxicity in bone marrow precursor cells. Previous studies demonstrated a correlation of such effects with the exposure of each individual to mutagenic phenomena, such as ionizing radiation, and the effects can persist for the lifetime of each individual. During the emergency response to the nuclear power plant accident at Chernobyl, Ukraine, USSR, a number of people were exposed to whole body doses of ionizing radiation. Some of these individuals were tested with this laser-based assay and found to express a dose-dependent increase in the frequency of variant red blood cells that appears to be a persistent biological effect. All data indicate that this assay might well be used as a biodosimeter to estimate radiation dose and also as an element to be used for estimating the risk of each individual to develop cancer due to radiation exposure. 17 refs., 5 figs.
Date: September 12, 1990
Creator: Jensen, R.H.; Bigbee, W.L.; Langlois, R.G.; Grant, S.G. (Lawrence Livermore National Lab., CA (USA)); Pleshanov, P.G. (Ministerstvo Zdravookhraneniya SSSR, Moscow (USSR)); Chirkov, A.A. (Institut Biofiziki, Moscow (USSR)) et al.
Object Type: Article
System: The UNT Digital Library
Countercurrent flow limited (CCFL) heat flux in the high flux isotope reactor (HFIR) fuel element (open access)

Countercurrent flow limited (CCFL) heat flux in the high flux isotope reactor (HFIR) fuel element

The countercurrent flow (CCF) performance in the fuel element region of the HFIR is examined experimentally and theoretically. The fuel element consists of two concentric annuli filled with aluminum clad fuel plates of 1.27 mm thickness separated by 1.27 mm flow channels. The plates are curved as they go radially outward to accomplish constant flow channel width and constant metal-to-coolant ratio. A full-scale HFIR fuel element mock-up is studied in an adiabatic air-water CCF experiment. A review of CCF models for narrow channels is presented along with the treatment of CCFs in system of parallel channels. The experimental results are related to the existing models and a mechanistic model for the annular'' CCF in a narrow channel is developed that captures the data trends well. The results of the experiment are used to calculate the CCFL heat flux of the HFIR fuel assembly. It was determined that the HFIR fuel assembly can reject 0.62 Mw of thermal power in the CCFL situation. 31 refs., 17 figs.
Date: October 12, 1990
Creator: Ruggles, A.E.
Object Type: Report
System: The UNT Digital Library