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Burrs produced by end milling

Description: The operation of small precision mechanisms such as timers, switches, or actuators depends on burr-free, sharp-edged component parts. Traditional methods of producing these near-perfect edges on miniature parts are costly and not as precise or repeatable as some piecepart designs require. By controlling the size of burrs produced in machining operations, burr removal costs can be lowered, and the repeatability of the resulting edges improved. This investigation sought to determine how machining variables influence burr size in end-milling operations. It was concluded that the low feed rates which are commonly used in precision miniature machining create larger burrs than do more conventional feedrates. Dull tools double the size of burrs. Increasing the radial depth of cut also increases burr size on many edges. A single end-milling cut can produce eight different burrs. Burr properties vary noticeably even along a single edge. Burrs in 1018 steel, 6061-T6 aluminum, 303 Se, and 17-4 PH stainless were typically 0.003 inch thick. Burr heights ranged from 0.0001 to 0.070 inch. Conceptual and mathematical descriptions of burr formation have been developed.
Date: September 1, 1976
Creator: Gillespie, L. K.
Partner: UNT Libraries Government Documents Department

Thermal Decomposition of New and Aged LX-04 and PBX 9501

Description: One-Dimensional-Time-To-Explosion (ODTX) experiments were conducted to study the thermal decomposition of new and aged LX-04, PBX 9501, HMX class 1 and class 2, Estane and EstaneBDNPA-F (PBX 950 1 plasticized-binder) materials. New and aged LX-04 showed comparable decomposition kinetics. The data for aged PBX 9501 showed slightly longer explosion times at equivalent temperatures. Analysis of the error in time measurement is complicated by several experimental factors but the small time change appears to be experimentally significant. The results suggest that aged PBX 9501 is slightly more thermally stable. The thermal decomposition of these materials were modeled using a coupled thermal and heat transport code (chemical TOPAZ) using separate kinetics for HMX and binder decomposition. The current kinetic models describe the longer explosion times by the loss of plasticizer-binder constituent, which was more thermally reactive.
Date: April 9, 2002
Creator: Tran, T. D.; Tarver, Craig M.; Idar, D. J. & Rodin, W. A.
Partner: UNT Libraries Government Documents Department

Timing analysis of PWR fuel pin failures

Description: Research has been 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 bumup, 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-PFL/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 bumup. Using peaking factors commensurate widi actual bumups would result in longer intervals for both reactor designs. This document also contains appendices A through J of this report.
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

Measurement and control of cement set times in waste solidification

Description: Fixation of radioactive waste in concrete was investigated on laboratory scale. Some cement formulations containing simulated or actual sludges from the Savannah River Plant had set times that would be too short for reliable handling in plant equipment. Set times could be controlled by use of excess water, but the concrete forms produced had inferior strength. A commercial organic retarder was found to be effective for increasing set times of cement-sludge formulations. However, the dosage of retarder required to control set times of high-alumina cement formulations was 1.0 to 1.5 wt percent of dry solids, which is 5 to 10 times the normal dosage for Portland cements. Data were obtained to predict the optimum content of retarder and water.
Date: September 1, 1976
Creator: Stone, J. A. & d'Entremont, P. D.
Partner: UNT Libraries Government Documents Department

MULTICHANNEL ENERGY AND TIMING MEASUREMENTS WITH THE PEAK DETECTOR/DERANDOMIZER ASIC.

Description: The Peak Detector/Derandomizer ASIC (PDD) provides threshold discrimination, peak detection, time-to-amplitude conversion, analog memory, sparsification, and multiplexing for 32 channels of analog pulse data. In this work the spectroscopic capabilities of the chip (high resolution and high rate) are demonstrated along with correlated measurements of pulse risetime. Imaging and coincidence detection using the PDD chip will also be illustrated.
Date: October 16, 2004
Creator: O'CONNOR,P.; DE GERONIMO,G.; GROSHOLZ,J.; KANDASAMY,A.; JUNNARKAR,S. & FRIED,J.
Partner: UNT Libraries Government Documents Department

Thermal Decomposition of New and Aged LX-04 and PBX 9501

Description: One-Dimensional-Time-To-Explosion (ODTX) experiments were conducted to study the thermal decomposition of aged LX-04, aged PBX 9501, HMX class 1 and class 2, Estane and Estane/BDNPA-F (PBX 950 1 plasticized-binder) materials. The tests involved heating 12.7 mm diameter spherical samples in pre-heated aluminum anvils until explosion. The times to explosion at different heating temperatures were compared to historical data on new LX-04 and PBX 9501 compounds to study any changes to their thermal stability. New and aged LX-04 showed comparable decomposition kinetics. The data for aged PBX 9501 showed slightly longer explosion times at equivalent temperatures. Analysis of the error in time measurement is limited and complicated by several experimental factors but the small time change appears to be experimentally significant. The thermal decomposition of these PBXs were modeled using a coupled thermal and heat transport code (chemical TOPAZ) using separate kinetics for HMX and binder decomposition. Separate decomposition models were developed for HMX and the reactive PBX 9501 binder component (1:1 Estane:BDNPA/F) based on the measured explosion times. Thermal aging models can describe longer explosion times by the loss of plasticizer-binder constituent which was more thermally reactive.
Date: March 25, 2002
Creator: Tran, T. D.; Tarver, Craig M. & Idar, D. J.
Partner: UNT Libraries Government Documents Department

A Minor Modification of Leading Edge Discriminator Circuitry with a Delay Line for Baseline Restoration of Scintillation Detectors

Description: Multi-channel neutron time-of-flight detector arrays LaNSA, T-ion, Medusa, and Mandala, have been used for neutron spectroscopy in inertial confinement fusion experiments. These multi-channel neutron detector arrays consist of many identical scintillation detectors (842 {approx} 1024 channel), data acquisition electronics (discriminators, time-to digital converters, and controller). Each detector element is operated in neutron counting mode. Time-of-flight of individual detected neutrons are recorded by time to digital converters. The energy of each detected neutrons is determined from its time-of-flight. The accurate time measurement ({Delta}t {approx} 0.5 ns) and straightforward statistical features of the data obtained with these systems provides good integrity and reliability. The elements detector used in these systems are organic scintillators coupled with photo multiplier tubes. A scintillation detector operated in particle-counting mode requires finite recovery time after each detection event. The recovery time is determined by the time responses of scintillators, photo multiplier tubes, and the dead times of following discriminators and time-to digital converters. The harsh gamma ray background environment of fast ignitor experiments requires detectors that have fast recovery times. In high intensity laser experiments (I > 10{sup 19} W/cm{sup 2}), strong gamma ray bursts are produced by relativistic laser plasma interactions. Prior to the neutron signal, these strong gamma ray bursts hit the detectors and interfere with the detection of following neutron signals. In these situations, the recovery time of the system after preceding gamma ray bursts is determined mainly by the base line shift of the PMT signal (due to slower decay components of scintillators ''after glow''). Discriminators cannot detect following signal pulses until the proceeding burst decays below its threshold voltage. The base line shift caused by the after glow prolongs the recovery time of the discriminators. Typical organic scintillators have slow decay component with 300 {approx} 600 nsec.
Date: May 27, 2003
Creator: Izumi, N
Partner: UNT Libraries Government Documents Department

NCPV Process Integration Project: Purpose, Status and Direction

Description: The primary purpose of the process integration project of the National Center for Photovoltaics (NCPV) is to develop an infrastructure that will allow researchers to gain new knowledge that is difficult-if not impossible-to obtain with existing equipment. This difficulty is due, in part, to the state of our existing tool set, which lacks sufficient in-situ or real-time measurement capabilities, or lacks access to analytical tools where the sample remains in a controlled environment between deposition and processing or measurement. This new infrastructure will provide flexible and robust integration of deposition, processing (etching, annealing, etc.), and characterization tools via a standardized transfer interface such that samples move between tools in a controlled ambient. The standardization of control and data acquisition software schemes, sample handling, and equipment components will allow us to perform research more efficiently; facilitating collaborations and technique development.
Date: February 1, 2005
Creator: Nelson, B.; Robbins, S. & Sheldon, P.
Partner: UNT Libraries Government Documents Department

Silicon drift chamber studies for possible use at RHIC. Final report, March 1, 1989--April 30, 1993

Description: This is the final report for the DOE project ``Silicon Drift-Chamber studies for Possible use at RHIC`` carried out at the University of Pittsburgh by T. J. Humanic. This study was carried out during the period March 1989--April 1993 under DOE Grant No. DE-FG02-89ER40503. The termination of this grant was caused by the movement of the principal investigator from the University of Pittsburgh to Ohio State University, where this work is continuing under a different grant. During this period we investigated various aspects of silicon drift chambers including two-track resolution, effects of external magnetic fields and different detector designs.
Date: August 27, 1993
Creator: Humanic, T. J.
Partner: UNT Libraries Government Documents Department

Global Positioning System receiver evaluation results

Description: A Sandia project currently uses an outdated Magnavox 6400 Global Positioning System (GPS) receiver as the core of its navigation system. The goal of this study was to analyze the performance of the current GPS receiver compared to newer, less expensive models and to make recommendations on how to improve the performance of the overall navigation system. This paper discusses the test methodology used to experimentally analyze the performance of different GPS receivers, the test results, and recommendations on how an upgrade should proceed. Appendices contain detailed information regarding the raw data, test hardware, and test software.
Date: September 1, 1993
Creator: Byrne, R. H.
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

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

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

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

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

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

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

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