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The Fermilab D0 Master Clock System

Description: The Clock System provides bunch crossing related timing signals to various detector subsystems. Accelerator synchronization and monitoring as well as timing signal generation and distribution are discussed. The system is built using three module types implemented in Eurostandard hardware with a VME communications interface. The first two types of modules are used to facilitate synchronization with the accelerator and to generate 23 timing signals that are programmable with one RF bucket (18.8 ns) resolution and 1 ns accuracy. Fifty-four of the third module type are used to distribute the timing signals and two synchronous 53 MHz and 106 MHz clocks to various detector subsystems. 6 refs., 5 figs.
Date: November 1, 1991
Creator: Rotolo, C.; Fachin, M.; Chappa, S.; Rauch, M.; Needles, C. & Dyer, A.
Partner: UNT Libraries Government Documents Department

Data acquisition system time measurement capabilities using WorkBench{trademark} software

Description: There is an increasing interest in the ability to measure transient behavior in the Heat Transfer Laboratory (HTL). To accomplish this the timing system behavior for the Data Acquisition Systems (DAS) must be evaluated. This report discusses the evaluation of a DAS timing system using WorkBench{trademark} Software in a Macintosh II environment. It also describes a method which can be successfully used to calibrate the timing system associated with the DAS.
Date: April 1, 1992
Creator: Coutts, D. A.
Partner: UNT Libraries Government Documents Department

Prototype CCD system for the time projection chamber

Description: A prototype sixteen channel charge-coupled device (CCD) system has been constructed for use with the prototype Time Projection Chamber (TPC) installed at the Bevalac at LBL. The system stores and digitizes analog pulse height information as a function of time from a set of proportional wires or cathode pads and provides the TPC with a true three-dimensional spatial readout. The performance of the system was found to be comparable to that of an equivalent ADC system.
Date: October 1, 1978
Creator: Fancher, D.L.; Lee, K.L.; Mallet, J.; Martin, P. & Shapiro, G.
Partner: UNT Libraries Government Documents Department

Laser mass spectrometric studies of high temperature superconductor ablation

Description: Laser ablation of bulk High Temperature Superconductor (HTS) material promises to provide a useful means of producing high quality HTS thin films. Mass spectrometric probes of the ablation plume provide a microscopic understanding of the ablation event and plume development as well as providing a process monitor for the thin film production. Detection of the nascent ions in the plume provides real time analytical information, e.g., identification of impurities, major and minor ablation species, etc. The common contaminants sodium and strontium have been easily detected by this technique in a variety of different HTS bulk materials. In contrast, detection of the ablated neutral species by Resonance Ionization Mass Spectrometry (RIMS) provides physical information about the ablation process. Time-of-flight/RIMS detection of Cu, Y, and BaO ablated from YBa{sub 2}Cu{sub 3}O{sub x} indicates the ablation involves post-desorption gas phase collisions, thereby influencing the ablation chemistry and dynamics (e.g., angular and velocity distributions). Approximately equal velocities are observed for all neutral species at constant ablation laser fluence. 17 refs., 4 figs.
Date: January 1, 1990
Creator: Estler, R.C. & Nogar, N.S.
Partner: UNT Libraries Government Documents Department

Data acquisition system time measurement capabilities using WorkBench[trademark] software

Description: There is an increasing interest in the ability to measure transient behavior in the Heat Transfer Laboratory (HTL). To accomplish this the timing system behavior for the Data Acquisition Systems (DAS) must be evaluated. This report discusses the evaluation of a DAS timing system using WorkBench[trademark] Software in a Macintosh II environment. It also describes a method which can be successfully used to calibrate the timing system associated with the DAS.
Date: April 1, 1992
Creator: Coutts, D.A.
Partner: UNT Libraries Government Documents Department

Timing analysis of PWR fuel pin failures

Description: This report discusses research conducted to develop and demonstrate a methodology for calculation of the time interval between receipt of the containment isolation signals and the first fuel pin failure for loss-of-coolant accidents (LOCAs). Demonstration calculations were performed for a Babcock and Wilcox (B W) design (Oconee) and a Westinghouse (W) four-loop design (Seabrook). Sensitivity studies were performed to assess the impacts of fuel pin burnup, axial peaking factor, break size, emergency core cooling system availability, and main coolant pump trip on these times. The analysis was performed using the following codes: FRAPCON-2, for the calculation of steady-state fuel behavior; SCDAP/RELAP5/MOD3 and TRACPF1/MOD1, for the calculation of the transient thermal-hydraulic conditions in the reactor system; and FRAP-T6, for the calculation of transient fuel behavior. In addition to the calculation of fuel pin failure timing, this analysis provides a comparison of the predicted results of SCDAP/RELAP5/MOD3 and TRAC-PF1/MOD1 for large-break LOCA analysis. Using SCDAP/RELAP5/MOD3 thermal-hydraulic data, the shortest time intervals calculated between initiation of containment isolation and fuel pin failure are 10.4 seconds and 19.1 seconds for the B W and W plants, respectively. Using data generated by TRAC-PF1/MOD1, the shortest intervals are 10.3 seconds and 29.1 seconds for the B W and W plants, respectively. These intervals are for a double-ended, offset-shear, cold leg break, using the technical specification maximum peaking factor and applied to fuel with maximum design burnup. Using peaking factors commensurate with actual burnups would result in longer intervals for both reactor designs. This document provides appendices K and L of this report which provide plots for the timing analysis of PWR fuel pin failures for Oconee and Seabrook respectively.
Date: September 1, 1992
Creator: Jones, K.R.; Wade, N.L.; Katsma, K.R.; Siefken, L.J. (EG and G Idaho, Inc., Idaho Falls, ID (United States)) & Straka, M. (Halliburton NUS, Idaho Falls, ID (United States))
Partner: UNT Libraries Government Documents Department

Panel mounted time code reader. [Day of year, hour, minute, second from standard Inter Range Instrumentation Group time codes]

Description: The time code reader described is composed of an assembly of commonly available electronic components logically arranged to minimize component count while reliably achieving the basic function of decoding and displaying the time of year information which is available in each of several standard Inter Range Instrumentation Group (IRIG) time codes. The time code reader omits all subsidiary functions of the code except that of retrieving a readable time of year (day, hour, minute, second). The reader can be mounted on any equipment panel having an available flat surface that is 2 by 6 inches in dimensions. IRIG time codes A, B, E, and G can be read without the necessity of switching, and a relatively wide range of input voltages is accommodated.
Date: February 1, 1978
Creator: Shaum, R. L.
Partner: UNT Libraries Government Documents Department

The Fermilab D0 Master Clock System

Description: The Clock System provides bunch crossing related timing signals to various detector subsystems. Accelerator synchronization and monitoring as well as timing signal generation and distribution are discussed. The system is built using three module types implemented in Eurostandard hardware with a VME communications interface. The first two types of modules are used to facilitate synchronization with the accelerator and to generate 23 timing signals that are programmable with one RF bucket (18.8 ns) resolution and 1 ns accuracy. Fifty-four of the third module type are used to distribute the timing signals and two synchronous 53 MHz and 106 MHz clocks to various detector subsystems. 6 refs., 5 figs.
Date: November 1, 1991
Creator: Rotolo, C.; Fachin, M.; Chappa, S.; Rauch, M.; Needles, C. & Dyer, A.
Partner: UNT Libraries Government Documents Department

Use of the delta-t method for setting rf phase and amplitude for the AHF linac

Description: The delta-t procedure is a time-of-flight method of finding set points for the rf phase and amplitude for each module of a linac. Expected errors for LAMPF afterburner linacs which might be used for an advanced hadron facility (AHF) are calculated. The modified delta-t procedure used on modules 13 through 48 of the present linac appears adequate to set up the proposed AHF linacs. 24 refs., 7 figs., 1 tab.
Date: January 1, 1989
Creator: Swain, G.R.
Partner: UNT Libraries Government Documents Department

A method for measuring the time structure of synchrotron x-ray beams

Description: We describe a method employing a plastic scintillator coupled to a fast photomultiplier tube to generate a timing pulse from the x-ray bursts emitted from a synchrotron radiation source. This technique is useful for performing synchrotron experiments where detailed knowledge of the timing distribution is necessary, such as time resolved spectroscopy or fluorescence lifetime experiments. By digitizing the time difference between the timing signal generated on one beam crossing with the timing signal generated on the next beam crossing, the time structure of a synchrotron beam can be analyzed. Using this technique, we have investigated the single bunch time structure at the National Synchrotron Light Source (NSLS) during pilot runs in January, 1989, and found that the majority of the beam (96%) is contained in one rf bucket, while the remainder of the beam (4%) is contained in satellite rf buckets preceeding and following the main rf bucket by 19 ns. 1 ref., 4 figs.
Date: August 1, 1989
Creator: Moses, W.W. & Derenzo, S.E. (Lawrence Berkeley Lab., CA (USA))
Partner: UNT Libraries Government Documents Department

Upgrading Amerada-type survey clocks for high-temperature geothermal service

Description: The Amerada type subsurface recording gauges have been used by the oil and gas industry for many years. These mechanical logging instruments are currently used by the growing geothermal industry. As the gauges were designed for service in low-temperature oil and gas wells, a significant number of failures are occurring at elevated geothermal temperatures. The spring-driven mechanical survey clocks appear to be the primary cause of these failures. The clock mechanisms tend to stop or lock-up when exposed to temperatures as high as 300/sup 0/C. A project that was undertaken to upgrade the survey clocks to 300/sup 0/C capability is summarized. The major problems causing clock failure were determined and were rectified by minor modifications and lubrication of the moving parts. Several clocks so modified performed reliably, both during laboratory oven tests and during field tests performed in actual geothermal wells at temperatures up to 330/sup 0/C.
Date: April 1, 1980
Creator: Major, B.H. & Witten, C.L.
Partner: UNT Libraries Government Documents Department

Estimated radiation dose from timepieces containing tritium

Description: Luminescent timepieces containing radioactive tritium, either in elemental form or incorporated into paint, are available to the general public. The purpose of this study was to estimate potential radiation dose commitments received by the public annually as a result of exposure to tritium which may escape from the timepieces during their distribution, use, repair, and disposal. Much uncertainty is associated with final dose estimates due to limitations of empirical data from which exposure parameters were derived. Maximum individual dose estimates were generally less than 3 ..mu..Sv/yr, but ranged up to 2 mSv under worst-case conditions postulated. Estimated annual collective (population) doses were less than 5 person/Sv per million timepieces distributed.
Date: January 1, 1980
Creator: McDowell-Boyer, L M
Partner: UNT Libraries Government Documents Department

SAMPLE: software for VAX FORTRAN execution timing

Description: SAMPLE is a set of subroutines in use at the Los Alamos National Laboratory for collecting CPU timings of various FORTRAN program sections - usually individual subroutines. These measurements have been useful in making programs run faster. The presentation includes a description of the software and examples of its use. The software is available on the directory (SAMPLE) of the VAX SIG tape.
Date: January 1, 1983
Creator: Lowe, L.H.
Partner: UNT Libraries Government Documents Department

Neutron cross sections of importance to astrophysics

Description: Neutron reactions of importance to the various stellar burning cycles are discussed. The role of isomeric states in the branched s-process is considered for particular cases. Neutron cross section needs for the /sup 187/Re-/sup 187/Os, /sup 87/Rb-/sup 87/Sr clocks for nuclear cosmochronology are discussed. Other reactions of interest to astrophysical processes are presented. 35 references.
Date: January 1, 1979
Creator: Browne, J.C.
Partner: UNT Libraries Government Documents Department

Summary of activity. Topic I: detectors and experiments. [High-energy detectors for use at ISABELLE]

Description: Results of a workshop studying detectors for Isabelle experimental halls are described. The detectors must be very reliable. Spatial resolution of the tracking detectors must be high to provide accurate measurements of angle and momentum, retain a short resolving time, and show excellent multiparticle handling capability. Included in the study were hodoscopes, drift chambers, proportional chambers, time projection chambers, Cherenkov counters, electromagnetic shower detectors, and hadron calorimeters. Data handling methods were also included in the studies. (FS)
Date: unknown
Creator: Marx, J. & Ozaki, S.
Partner: UNT Libraries Government Documents Department

Soviet precision timekeeping research and technology

Description: This report is the result of a study of Soviet progress in precision timekeeping research and timekeeping capability during the last two decades. The study was conducted by a panel of seven US scientists who have expertise in timekeeping, frequency control, time dissemination, and the direct applications of these disciplines to scientific investigation. The following topics are addressed in this report: generation of time by atomic clocks at the present level of their technology, new and emerging technologies related to atomic clocks, time and frequency transfer technology, statistical processes involving metrological applications of time and frequency, applications of precise time and frequency to scientific investigations, supporting timekeeping technology, and a comparison of Soviet research efforts with those of the United States and the West. The number of Soviet professionals working in this field is roughly 10 times that in the United States. The Soviet Union has facilities for large-scale production of frequency standards and has concentrated its efforts on developing and producing rubidium gas cell devices (relatively compact, low-cost frequency standards of modest accuracy and stability) and atomic hydrogen masers (relatively large, high-cost standards of modest accuracy and high stability). 203 refs., 45 figs., 9 tabs.
Date: August 1, 1991
Creator: Vessot, R.F.C.; Allan, D.W.; Crampton, S.J.B.; Cutler, L.S.; Kern, R.H.; McCoubrey, A.O. et al.
Partner: UNT Libraries Government Documents Department

Linking Automated Data Analysis and Visualization with Applications in Developmental Biology and High-Energy Physics

Description: Knowledge discovery from large and complex collections of today's scientific datasets is a challenging task. With the ability to measure and simulate more processes at increasingly finer spatial and temporal scales, the increasing number of data dimensions and data objects is presenting tremendous challenges for data analysis and effective data exploration methods and tools. Researchers are overwhelmed with data and standard tools are often insufficient to enable effective data analysis and knowledge discovery. The main objective of this thesis is to provide important new capabilities to accelerate scientific knowledge discovery form large, complex, and multivariate scientific data. The research covered in this thesis addresses these scientific challenges using a combination of scientific visualization, information visualization, automated data analysis, and other enabling technologies, such as efficient data management. The effectiveness of the proposed analysis methods is demonstrated via applications in two distinct scientific research fields, namely developmental biology and high-energy physics.Advances in microscopy, image analysis, and embryo registration enable for the first time measurement of gene expression at cellular resolution for entire organisms. Analysis of high-dimensional spatial gene expression datasets is a challenging task. By integrating data clustering and visualization, analysis of complex, time-varying, spatial gene expression patterns and their formation becomes possible. The analysis framework MATLAB and the visualization have been integrated, making advanced analysis tools accessible to biologist and enabling bioinformatic researchers to directly integrate their analysis with the visualization. Laser wakefield particle accelerators (LWFAs) promise to be a new compact source of high-energy particles and radiation, with wide applications ranging from medicine to physics. To gain insight into the complex physical processes of particle acceleration, physicists model LWFAs computationally. The datasets produced by LWFA simulations are (i) extremely large, (ii) of varying spatial and temporal resolution, (iii) heterogeneous, and (iv) high-dimensional, making analysis and knowledge discovery from complex ...
Date: November 20, 2009
Creator: Ruebel, Oliver
Partner: UNT Libraries Government Documents Department

Organic light emitting diodes (OLEDS) and OLED-based structurally integrated optical sensors

Description: General introduction to OLED basics and OLED-based structurally integrated sensors was provided in chapter 1 and chapter 2. As discussed in chapter 3, OLEDs were developed or improved using novel engineering methods for better charge injection (increased by over 1 order of magnitude) and efficiency. As the excitation sources, these OLEDs have preferred characteristics for sensor applications, including narrowed emission, emission at desired wavelength, and enhanced output for reduced EL background, higher absorption and improved device lifetime. In addition to OLEDs with desired performance, sensor integration requires oxidase immobilization with the sensor film for O<sub>2</sub>-based biological and chemical sensing. Nanoparticles such as ZnO have large surface area and high isoelectric point (~9.5), which favors enzyme immobilization via physical adsorption as well as Coulombic bonding. In chapter 4, it was demonstrated that ZnO could be used for this purpose, although future work is needed to further bond the ZnO to the sensor film. In chapter 5, single unit sensor was extended to multianalyte parallel sensing based on an OLED platform, which is compact and integrated with silicon photodiodes and electronics. Lactate and glucose were simultaneously monitored with a low limit of detection 0.02 mM, fast response time (~1 minute) and dynamic range from 0-8.6 ppm of dissolved oxygen. As discovered in previous work, the dynamic range covers 0-100% gas phase O<sub>2</sub> or 0-40 ppm dissolved oxygen at room temperature. PL decay curve, which is used to extract the decay time, is usually not a simple exponential at high O<sub>2</sub> concentration, which indicates that O<sub>2</sub> is not equally accessible for different luminescent sites. This creates a challenge for data analysis, which however was successfully processed by stretched exponential as shown in chapter 6. This also provides an insight about the distribution of O<sub>2</sub>:dye collisional quenching rate due to microheterogeneity. Effect of TiO<sub>2</sub> ...
Date: January 1, 2010
Creator: Cai, Yuankun
Partner: UNT Libraries Government Documents Department

Hi-Q Rotor - Low Wind Speed Technology

Description: The project objective was to optimize the performance of the Hi-Q Rotor. Early research funded by the California Energy Commission indicated the design might be advantageous over state-of-the-art turbines for collecting wind energy in low wind conditions. The Hi-Q Rotor is a new kind of rotor targeted for harvesting wind in Class 2, 3, and 4 sites, and has application in areas that are closer to cities, or 'load centers.' An advantage of the Hi-Q Rotor is that the rotor has non-conventional blade tips, producing less turbulence, and is quieter than standard wind turbine blades which is critical to the low-wind populated urban sites. Unlike state-of-the-art propeller type blades, the Hi-Q Rotor has six blades connected by end caps. In this phase of the research funded by DOE's Inventions and Innovation Program, the goal was to improve the current design by building a series of theoretical and numeric models, and composite prototypes to determine a best of class device. Development of the rotor was performed by aeronautical engineering and design firm, DARcorporation. From this investigation, an optimized design was determined and an 8-foot diameter, full-scale rotor was built and mounted using a Bergey LX-1 generator and furling system which were adapted to support the rotor. The Hi-Q Rotor was then tested side-by-side against the state-of-the-art Bergey XL-1 at the Alternative Energy Institute's Wind Test Center at West Texas State University for six weeks, and real time measurements of power generated were collected and compared. Early wind tunnel testing showed that the cut-in-speed of the Hi-Q rotor is much lower than a conventional tested HAWT enabling the Hi-Q Wind Turbine to begin collecting energy before a conventional HAWT has started spinning. Also, torque at low wind speeds for the Hi-Q Wind Turbine is higher than the tested conventional HAWT and enabled ...
Date: January 11, 2010
Creator: Mills, Todd E. & Tatum, Judy
Partner: UNT Libraries Government Documents Department

Vogtle Electric Generating Plant ETE Analysis Review

Description: Under contract with the Nuclear Regulatory Commission (NRC), staff from Pacific Northwest National Laboratory (PNNL) and Sandia National Laboratory (SNL)-Albuquerque reviewed the evacuation time estimate (ETE) analysis dated April 2006 prepared by IEM for the Vogtle Electric Generating Plant (VEGP). The ETE analysis was reviewed for consistency with federal regulations using the NRC guidelines in Review Standard (RS)-002, Supplement 2 and Appendix 4 to NUREG-0654, and NUREG/CR-4831. Additional sources of information referenced in the analysis and used in the review included NUREG/CR-6863 and NUREG/CR-6864. The PNNL report includes general comments, data needs or clarifications, and requests for additional information (RAI) resulting from review of the ETE analysis.
Date: December 9, 2006
Creator: Diediker, Nona H. & Jones, Joe A.
Partner: UNT Libraries Government Documents Department

Surface Radiation Survey at the Shepley’s Hill Remediation Site, Devens, Massachusettes

Description: The Idaho National Laboratory (INL) provided technical support for ongoing environmental remediation activities at the Shepley’s Hill remediation site, near Devens, MA. The technical support included the completion of a radiation survey of naturally occurring radioactive materials (NORM) at Shepley’s Hill, Shepley’s Hill landfill cover, and Red Cove areas. The objective of the radiation survey was to assess the ability of the INL backpack sodium iodide spectroscopy (BaSIS) system to detect elevated levels of NORM that may be associated with radon-222 emanation from near surface and subsurface fractures in the area. It is postulated that these fracture zones provide subsurface conduits for the transport of environmental contaminants. As such, location of these fracture sets will proved EPA Region 1 with the means for completing the development of an accurate site conceptual model. The results of the radiological survey show that some of the radiological anomalies correlate with currently mapped rock outcrops; however, not all of the rock outcrops in the surveyed area have been mapped. As such, it is not conclusive that all of the radiological anomalies correspond with surface rock outcrops. EPA Region 1 intends to perform a more comprehensive correlation of the radiation data collected with the BaSIS system with additional data sets such as detailed bedrock structural mapping, 2-dimensional resistivity profiling, and high-resolution topographic mapping. The results of this effort will be used in consideration of designing a potential follow-on effort for mapping of radon.
Date: September 1, 2009
Creator: Giles, J. R.; Oertel, C. P. & Roybal, L. G.
Partner: UNT Libraries Government Documents Department