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1 nA beam position monitoring system (open access)

1 nA beam position monitoring system

A system has been developed at Jefferson Lab for measuring transverse position of very low current beams delivered to the Experimental Hall B of the Continuous Electron Beam Accelerator Facility (CEBAF). At the heart of the system is a position sensitive cavity operating at 1497 MHz. The cavity utilizes a unique design which achieves a high sensitivity to beam position at a relatively low cavity Q. The cavity output RF signal is processed using a down-converter and a commercial lock-in amplifier operating at 100 kHz. The system interfaces with a VME based EPICS control system using the IEEE, 488 bus. The main features of the system are simple and robust design, and wide dynamic range capable of handling beam currents from 1 nA to 1000 nA with an expected resolution better than 100 {mu}m. This paper outlines the design of the system.
Date: June 1, 1997
Creator: Ursic, R.; Flood, R. & Piller, C.
Object Type: Article
System: The UNT Digital Library
A 2.14 ms candidate optical pulsar in SN1987A: Ten years after (open access)

A 2.14 ms candidate optical pulsar in SN1987A: Ten years after

We have monitored Supernova 1987A in optical/near-infrared bands from a few weeks following its birth until the present time in order to search for a pulsar remnant. We have found an apparent pattern of emission near the frequency of 467.5 Hz - a 2.14 ms pulsar candidate, first detected in data taken on the remnant at the Las Campanas Observatory (LCO) 2.5-m Dupont telescope during 14-16 Feb. 1992 UT. We detected further signals near the 2.14 ms period on numerous occasions over the next four years in data taken with a variety of telescopes, data systems and detectors, at a number of ground- and space-based observatories. The sequence of detections of this signal from Feb. `92 through August `93, prior to its apparent subsequent fading, is highly improbable (< 10{sup -10} for any noise source). We also find evidence for modulation of the 2.14 ms period with a {approx}1,000 s period which, when taken with the high spindown of the source (2-3 x 10{sup -10} Hz/s), is consistent with precession and spindown via gravitational radiation of a neutron star with a non- axisymmetric oblateness of {approx}10{sup -6}, and an implied gravitational luminosity exceeding that of the Crab Nebula pulsar by …
Date: September 1, 1997
Creator: Middleditch, J.; Kristian, J. A.; Kunkel, W. E.; Hill, K. M. & Watson, R. D.
Object Type: Article
System: The UNT Digital Library
3-d finite element model development for biomechanics: a software demonstration (open access)

3-d finite element model development for biomechanics: a software demonstration

Finite element analysis is becoming an increasingly important part of biomechanics and orthopedic research, as computational resources become more powerful, and data handling algorithms become more sophisticated. Until recently, tools with sufficient power did not exist or were not accessible to adequately model complicated, three-dimensional, nonlinear biomechanical systems. In the past, finite element analyses in biomechanics have often been limited to two-dimensional approaches, linear analyses, or simulations of single tissue types. Today, we have the resources to model fully three-dimensional, nonlinear, multi-tissue, and even multi-joint systems. The authors will present the process of developing these kinds of finite element models, using human hand and knee examples, and will demonstrate their software tools.
Date: March 1, 1997
Creator: Hollerbach, K.; Hollister, A.M. & Ashby, E.
Object Type: Article
System: The UNT Digital Library
A 3-d modular gripper design tool (open access)

A 3-d modular gripper design tool

Modular fixturing kits are precisely machined sets of components used for flexible, short-turnaround construction of fixtures for a variety of manufacturing purposes. A modular vise is a parallel-jaw vise, where each jaw is a modular fixture plate with a regular grid of precisely positioned holes. A modular vise can be used to locate and hold parts for machining, assembly, and inspection tasks. To fixture a part, one places pins in some of the holes so that when the vise is closed, the part is reliably located and completely constrained. The modular vise concept can be adapted easily to the design of modular parallel-jaw grippers for robots. By attaching a grid plate to each jaw of a parallel-jaw gripper, the authors gain the ability to easily construct high-quality grasps for a wide variety of parts from a standard set of hardware. Wallack and Canny developed a previous algorithm for planning planar grasp configurations for the modular vise. In this paper, the authors expand this work to produce a 3-d fixture/gripper design tool. They describe several analyses added to the planar algorithm to improve its utility, including a three-dimensional grasp quality metric based on geometric and force information, three-dimensional geometric loading analysis, …
Date: January 1, 1997
Creator: Brown, R.G. & Brost, R.C.
Object Type: Report
System: The UNT Digital Library
A 3-d modular gripper design tool (open access)

A 3-d modular gripper design tool

Modular fixturing kits are sets of components used for flexible, rapid construction of fixtures. A modular vise is a parallel-jaw vise, each jaw of which is a modular fixture plate with a regular grid of precisely positioned holes. To fixture a part, one places pins in some of the holes so that when the vise is closed, the part is reliably located and completely constrained. The modular vise concept can be adapted easily to the design of modular parallel-jaw grippers for robots. By attaching a grid-plate to each jaw of a parallel-jaw gripper, one gains the ability to easily construct high-quality grasps for a wide variety of parts from a standard set of hardware. Wallack and Canny developed an algorithm for planning planar grasp configurations for the modular vise. In this paper, the authors expand this work to produce a 3-d fixture/gripper design tool. They describe several analyses they have added to the planar algorithm, including a 3-d grasp quality metric based on force information, 3-d geometric loading analysis, and inter-gripper interference analysis. Finally, the authors describe two applications of their code. One of these is an internal application at Sandia, while the other shows a potential use of the …
Date: February 1, 1997
Creator: Brown, R.G. & Brost, R.C.
Object Type: Article
System: The UNT Digital Library
3-D Spectral Induced Polarization (IP) Imaging: Non-Invasive Characterization Of Contaminant Plumes (open access)

3-D Spectral Induced Polarization (IP) Imaging: Non-Invasive Characterization Of Contaminant Plumes

The overall objective of this project is to develop the scientific basis for characterizing contaminant plumes in the earth's subsurface using field measurements of induced polarization (IP) effects. Three specific objectives towards this end are 1. 2. 3. Understanding IP at the laboratory level through measurements of complex resistivity as a function of frequency in rock and soil samples with varying pore geometries, pore fluid conductivities and saturations, and contaminant chemistries and concentrations. Developing effective data acquisition techniques for measuring the critical IP responses (time domain or frequency domain) in the field. Developing modeling and inversion algorithms that permit the interpretation of field IP data in terms of subsurface geology and contaminant plume properties.
Date: June 1, 1997
Creator: Morgan, Dale F.; Lesmes, David P.; Rodi, William; Shi, Weiqun; Frye, Kevin, M. & Sturrock, John
Object Type: Report
System: The UNT Digital Library
3-D spectral IP imaging: Non-invasive characterization of contaminant plumes. Annual progress report, September 15, 1996--September 14, 1997 (open access)

3-D spectral IP imaging: Non-invasive characterization of contaminant plumes. Annual progress report, September 15, 1996--September 14, 1997

'The objective of this project is to develop the scientific basis for characterizing contaminant plumes in the earth''s subsurface using field measurements of induced polarization (IP) effects. The first-year accomplishments are (1) laboratory experiments on fluid-saturated sandstones quantifying the dependence of spectral IP responses on solution chemistry and rock micro-geometry; (2) library research on the current understanding of electromagnetic coupling effects on IP data acquired in the field: and (3) development of prototype forward modeling and inversion algorithms for interpreting IP data in terms of 3-D models of complex resistivity.'
Date: December 1, 1997
Creator: Frye, Kevin M.; Lesmes, David P.; Morgan, F. Dale; Rodi, William; Shi, Weiqun & Sturrock, John
Object Type: Report
System: The UNT Digital Library
4.5 Meter high level waste canister study (open access)

4.5 Meter high level waste canister study

The Tank Waste Remediation System (TWRS) Storage and Disposal Project has established the Immobilized High-Level Waste (IBLW) Storage Sub-Project to provide the capability to store Phase I and II BLW products generated by private vendors. A design/construction project, Project W-464, was established under the Sub-Project to provide the Phase I capability. Project W-464 will retrofit the Hanford Site Canister Storage Building (CSB) to accommodate the Phase I I-ILW products. Project W-464 conceptual design is currently being performed to interim store 3.0 m-long BLW stainless steel canisters with a 0.61 in diameter, DOE is considering using a 4.5 in canister of the same diameter to reduce permanent disposal costs. This study was performed to assess the impact of replacing the 3.0 in canister with the 4.5 in canister. The summary cost and schedule impacts are described.
Date: October 1, 1997
Creator: Calmus, R.B., Westinghouse Hanford, Richland, WA
Object Type: Report
System: The UNT Digital Library
5. annual clean coal technology conference: powering the next millennium. Volume 2 (open access)

5. annual clean coal technology conference: powering the next millennium. Volume 2

The Fifth Annual Clean Coal Technology Conference focuses on presenting strategies and approaches that will enable clean coal technologies to resolve the competing, interrelated demands for power, economic viability, and environmental constraints associated with the use of coal in the post-2000 era. The program addresses the dynamic changes that will result from utility competition and industry restructuring, and to the evolution of markets abroad. Current projections for electricity highlight the preferential role that electric power will have in accomplishing the long-range goals of most nations. Increase demands can be met by utilizing coal in technologies that achieve environmental goals while keeping the cost- per-unit of energy competitive. Results from projects in the DOE Clean Coal Technology Demonstration Program confirm that technology is the pathway to achieving these goals. The industry/government partnership, cemented over the past 10 years, is focused on moving the clean coal technologies into the domestic and international marketplaces. The Fifth Annual Clean Coal Technology Conference provides a forum to discuss these benchmark issues and the essential role and need for these technologies in the post-2000 era. This volume contains technical papers on: advanced coal process systems; advanced industrial systems; advanced cleanup systems; and advanced power generation systems. …
Date: June 1, 1997
Creator: unknown
Object Type: Article
System: The UNT Digital Library
5 MeV Mott Polarimeter Development at Jefferson Lab (open access)

5 MeV Mott Polarimeter Development at Jefferson Lab

Low energy (E{sub k}=100 keV) Mott scattering polarimeters are ill- suited to support operations foreseen for the polarized electron injector at Jefferson Lab. One solution is to measure the polarization at 5 MeV where multiple and plural scattering are unimportant and precision beam monitoring is straightforward. The higher injector beam current offsets the lower cross-sections. Recent improvements in the CEBAF injector polarimeter scattering chamber have improved signal to noise.
Date: January 1, 1997
Creator: Price, J. S.; Sinclair, C. K.; Cardman, L. S.; Haanskneccht, J.; Mack, D. J.; Piot, P. et al.
Object Type: Article
System: The UNT Digital Library
5 MeV Mott polarimeter for rapid precise electron beam polarization measurements (open access)

5 MeV Mott polarimeter for rapid precise electron beam polarization measurements

Low energy (E{sub k} = 100 keV) Mott scattering polarimeters are ill-suited to support operations foreseen for the polarized electron injector at Jefferson Lab. One solution is to measure the polarization at 5 MeV where multiple and plural scattering are unimportant and precision beam monitoring is straightforward. The higher injector beam current offsets the lower cross-sections; measured rates scale to 1 kHz/{mu}A with a 1 {mu}m thick gold target foil.
Date: November 1, 1997
Creator: Price, J. S.; Poelker, B. M. & Sinclair, C. K.
Object Type: Report
System: The UNT Digital Library
A 6.7 MeV cw RFQ linac (open access)

A 6.7 MeV cw RFQ linac

A 6.7-MeV 350 MHz, cw Radio Frequency Quadrupole proton linac has been designed and is being fabricated for the Accelerator Production of Tritium Project at Los Alamos. This eight-meter long structure consists of four resonantly-coupled segments and is being fabricated using hydrogen furnace brazing as a joining technology. Details of the design and status of fabrication are reported.
Date: August 1, 1997
Creator: Schrage, D.; Young, L.; Clark, W.; Davis, T.; Martinez, F.; Naranjo, A. et al.
Object Type: Article
System: The UNT Digital Library
10 microsecond time resolution studies of Cygnus X-1 (open access)

10 microsecond time resolution studies of Cygnus X-1

Time variability analyses have been applied to data composed of event times of X-rays emitted from the binary system Cygnus X-1 to search for unique black hole signatures. The X-ray data analyzed was collected at ten microsecond time resolution or better from two instruments, the High Energy Astrophysical Observatory (HEAO) A-1 detector and the Rossi X-ray Timing Explorer (XTE) Proportional Counter Array (PCA). HEAO A-1 and RXTE/PCA collected data from 1977--79 and from 1996 on with energy sensitivity from 1--25 keV and 2--60 keV, respectively. Variability characteristics predicted by various models of an accretion disk around a black hole have been searched for in the data. Drop-offs or quasi-periodic oscillations (QPOs) in the Fourier power spectra are expected from some of these models. The Fourier spectral technique was applied to the HEAO A-1 and RXTE/PCA data with careful consideration given for correcting the Poisson noise floor for instrumental effects. Evidence for a drop-off may be interpreted from the faster fall off in variability at frequencies greater than the observed breaks. Both breaks occur within the range of Keplerian frequencies associated with the inner edge radii of advection-dominated accretion disks predicted for Cyg X-1. The break between 10--20 Hz is also …
Date: June 1, 1997
Creator: Wen, H.C.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
13 point video tape quality guidelines (open access)

13 point video tape quality guidelines

Until high definition television (ATV) arrives, in the U.S. we must still contend with the National Television Systems Committee (NTSC) video standard (or PAL or SECAM-depending on your country). NTSC, a 40-year old standard designed for transmission of color video camera images over a small bandwidth, is not well suited for the sharp, full-color images that todays computers are capable of producing. PAL and SECAM also suffers from many of NTSC`s problems, but to varying degrees. Video professionals, when working with computer graphic (CG) images, use two monitors: a computer monitor for producing CGs and an NTSC monitor to view how a CG will look on video. More often than not, the NTSC image will differ significantly from the CG image, and outputting it to NTSC as an artist works enables the him or her to see the images as others will see it. Below are thirteen guidelines designed to increase the quality of computer graphics recorded onto video tape. Viewing your work in NTSC and attempting to follow the below tips will enable you to create higher quality videos. No video is perfect, so don`t expect to abide by every guideline every time.
Date: May 1, 1997
Creator: Gaunt, R.
Object Type: Article
System: The UNT Digital Library
The 16 August 1997 Novaya Zemlya seismic event as viewed from GSN stations KEV and KBS (open access)

The 16 August 1997 Novaya Zemlya seismic event as viewed from GSN stations KEV and KBS

Using current and historic seismic records from Global Seismic Network stations KEV and KBS, the authors find that S minus P arrival time comparisons between nuclear explosions and the 16 August 1997 seismic event (m{sub b} {approx} 3.6) from near Novaya Zemlya clearly indicate that (relative to KEV) the 16 August event occurred at least 80 km east of the Russian test site. Including S minus P arrival times from KBS constrains the location to beneath the Kara Sea and in good agreement with previously reported locations, over 100 km southeast of the test site. From an analysis of P{sub n}/S{sub n} waveform ratios at frequencies above 4 Hz, they find that the 16 August event falls within the population of regional earthquakes and is distinctly separated from Novaya Zemlya and other northern Eurasian nuclear explosion populations. Thus, given its location and waveform characteristics, they conclude the 16 August event was an earthquake. The 16 August event was not detected at teleseismic distances, and thus, this event provides a good example of the regional detection, location, and identification efforts that will be required to monitor the Comprehensive Test Ban Treaty below m{sub b} {approx} 4.
Date: November 1, 1997
Creator: Hartse, H.E.
Object Type: Report
System: The UNT Digital Library
24 M Meteorological Tower Data Report Period: January--December, 1994 (open access)

24 M Meteorological Tower Data Report Period: January--December, 1994

This report was prepared by the Desert Research Institute (DRI) for the U.S. Department of Energy (DOE). It summarizes meteorological data collected at the 24 meter tower at the Nevada Test Site Hazardous Material Spill Center (HAZMAT) located at Frenchman Flat near Mercury, Nevada, approximately 75 miles northwest of Las Vegas, Nevada. The tower was originally installed in July, 1993 to characterize baseline conditions for an EPA sponsored experimental research program at the HAZMAT.
Date: August 1, 1997
Creator: Freeman, D.; Bowen, J. & Egami, R.
Object Type: Report
System: The UNT Digital Library
24 M Meteorological Tower Data Report Period: January Through December, 1995 (open access)

24 M Meteorological Tower Data Report Period: January Through December, 1995

This report was prepared by the Desert Research Institute (DRI) for the US Department of Energy (DOE). It summarizes meteorological data collected at the 24 meter tower at the Nevada Test Site Hazardous Material Spill Center (HAZMAT) located at Frenchman Flat near Mercury, Nevada, approximately 75 miles northwest of Las Vegas, Nevada. The tower was originally installed in July, 1993 to characterize baseline conditions for an EPA sponsored experimental research program at the HAZMAT. A previous report reported monitoring results for 1994. This report presents results of the monitoring for January--December, 1995, providing: a status of the measurement systems (including any quality assurance activities) during the report period and a summary of the meteorological conditions at the HAZMAT during the report period. The scope of the report is limited to summary data analyses and does not include extensive meteorological analysis. The tower was instrumented at 8 levels. Wind speed, wind direction, and temperature were measured at all 8 levels. Relative humidity was measured at 3 levels. Solar and net radiation were measured at 2 meters above the ground. Barometric pressure was measured at the base of the tower and soil temperature was measured near the base of the tower.
Date: December 1, 1997
Creator: Freeman, D.; Bowen, J.B.; Egami, R.; Coulombe, W.; Crow, D.; Cristani, B. et al.
Object Type: Report
System: The UNT Digital Library
24 M Meteorological Tower Data Report Period: January Through December, 1996 (open access)

24 M Meteorological Tower Data Report Period: January Through December, 1996

This report was prepared by the Desert Research Institute (DRI) for the US Department of Energy (DOE). It summarizes meteorological data collected at the 24 meter tower at the Nevada Test Site Hazardous Material Spill Center (HAZMAT) located at Frenchman Flat near Mercury, Nevada, approximately 75 miles northwest of Las Vegas, Nevada. The tower was originally installed in July, 1993 to characterize baseline conditions for an EPA sponsored experimental research program at the HAZMAT. This report presents results of the monitoring for January--December, 1996, providing: a status of the measurement systems during the report period and a summary of the meteorological conditions at the HAZMAT during the report period. The scope of the report is limited to summary data analyses and does not include extensive meteorological analysis. The tower was instrumented at 8 levels. Wind speed, wind direction, and temperature were measured at all 8 levels. Relative humidity was measured at 3 levels. Solar and net radiation were measured at 2 meters above the ground. Barometric pressure was measured at the base of the tower and soil temperature was measured near the base of the tower.
Date: December 1, 1997
Creator: Freeman, D.; Bowen, J.; Egami, R.; Coulombe, W.; Crow, D.; Cristani, B. et al.
Object Type: Report
System: The UNT Digital Library
60 HZ beam motion reduction at NSLS UV storage ring (open access)

60 HZ beam motion reduction at NSLS UV storage ring

A significant reduction in 60 hz beam motion has been achieved in the UV storage ring. From the wide band harmonic beam motion signal, 60 hz signal is extracted by tuned bandpass filter. This signal is processed by the phase and amplitude adjustment circuits and then, it is fed into the harmonic orbit generation circuits. Several harmonics, near the tune, were canceled by employing one circuit for each harmonic. The design and description of this experiment is given in this paper. The results showing reduction in beam motion at 60 hz are also provided.
Date: January 1, 1997
Creator: Singh, O. V.
Object Type: Article
System: The UNT Digital Library
94-1 Research and development project lead laboratory support. Status report, January 1--March 31, 1997 (open access)

94-1 Research and development project lead laboratory support. Status report, January 1--March 31, 1997

This status report is published for Los Alamos National Laboratory 94-1 Research and Development Project Support. The Department of Energy Office of Environmental Management funds these projects in order to support the storage or disposal of legacy plutonium and plutonium-bearing materials that resulted from weapons production throughout the DOE complex. This report summarizes status and technical progress for Los Alamos 94-1 projects during the second quarter of fiscal year 1997.
Date: August 1, 1997
Creator: Rink, N.A.
Object Type: Report
System: The UNT Digital Library
94-1 Research and development project lead laboratory support. Status report, July 1, 1996--September 30, 1996 (open access)

94-1 Research and development project lead laboratory support. Status report, July 1, 1996--September 30, 1996

This document reports status and technical progress for Los Alamos 94-1 Research and Development projects. Updated schedule charts are shown in the appendix. This is the fourth status report published for Los Alamos National Laboratory 94-1 Research and Development Project Support. The Department of Energy Office of Environmental Management (DOE/EM) funds these projects in order to support the storage or disposal of legacy plutonium and plutonium-bearing materials resulting from weapons production throughout the DOE complex. This document also serves as an end-for-year review of projects and positions the program for FY97.
Date: March 1, 1997
Creator: Rink, N.
Object Type: Report
System: The UNT Digital Library
94-1 research and development project lead laboratory support. Status report, October 1--December 31, 1996 (open access)

94-1 research and development project lead laboratory support. Status report, October 1--December 31, 1996

This status report is published for Los Alamos National Laboratory 94-1 Research and Development (R and D) projects. The Department of Energy Office of Environmental Management (DOE/EM) funds these projects in order to support the storage or disposal of legacy plutonium and plutonium-bearing materials that resulted from weapons production throughout the DOE complex. This report summarizes status and technical progress for Materials Identification and Surveillance; Stabilization Process Development; Surveillance and Monitoring; Core Technology; Separations; Materials Science; Synthesis and Structural Characterization of Plutonium(IV) and Plutonium(VI) Phosphates; Plutonium Phosphate Solution Chemistry; and Molten Salt/Nonaqueous Electrochemistry.
Date: July 1, 1997
Creator: Rink, N.A.
Object Type: Report
System: The UNT Digital Library
100-D Ponds closure plan. Revision 1 (open access)

100-D Ponds closure plan. Revision 1

The 100-D Ponds is a Treatment, Storage, and Disposal (TSD) unit on the Hanford Facility that received both dangerous and nonregulated waste. This Closure Plan (Rev. 1) for the 100-D Ponds TSD unit consists of a RCRA Part A Dangerous Waste Permit Application (Rev. 3), a RCRA Closure Plan, and supporting information contained in the appendices to the plan. The closure plan consists of eight chapters containing facility description, process information, waste characteristics, and groundwater monitoring data. There are also chapters containing the closure strategy and performance standards. The strategy for the closure of the 100-D Ponds TSD unit is clean closure. Appendices A and B of the closure plan demonstrate that soil and groundwater beneath 100-D Ponds are below cleanup limits. All dangerous wastes or dangerous waste constituents or residues associated with the operation of the ponds have been removed, therefore, human health and the environment are protected. Discharges to the 100-D Ponds, which are located in the 100-DR-1 operable unit, were discontinued in June 1994. Contaminated sediment was removed from the ponds in August 1996. Subsequent sampling and analysis demonstrated that there is no contamination remaining in the ponds, therefore, this closure plan is a demonstration of clean …
Date: September 1, 1997
Creator: Petersen, S.W.
Object Type: Report
System: The UNT Digital Library
100 years of elementary particles [Beam Line, vol. 27, issue 1, Spring 1997] (open access)

100 years of elementary particles [Beam Line, vol. 27, issue 1, Spring 1997]

This issue of Beam Line commemorates the 100th anniversary of the April 30, 1897 report of the discovery of the electron by J.J. Thomson and the ensuing discovery of other subatomic particles. In the first three articles, theorists Abraham Pais, Steven Weinberg, and Chris Quigg provide their perspectives on the discoveries of elementary particles as well as the implications and future directions resulting from these discoveries. In the following three articles, Michael Riordan, Wolfgang Panofsky, and Virginia Trimble apply our knowledge about elementary particles to high-energy research, electronics technology, and understanding the origin and evolution of our Universe.
Date: April 1, 1997
Creator: Pais, Abraham; Weinberg, Steven; Quigg, Chris; Riordan, Michael; Panofsky, Wolfgang K.H. & Trimble, Virginia
Object Type: Report
System: The UNT Digital Library