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Laboratory scale tests of electrical impedence tomography

Description: Electrical impedance tomographs (magnitude and phase) of known, laboratory-scale targets are reported. Three methods are used to invert electrical impedance data and their tomographs compared. The first method uses an electrical resistance tomography (ERT) algonthm (designed for DC resistivity inversion) to perform impedance magnitude inversion and a linearized perturbation approach (PA) to invert the imaginary part. The second approximate method compares ERT magnitude inversions at two frequencies and uses the frequency effect (FE) to compute phase tomographs. The third approach, electrrcal impedance tomography (EIT), employs fully complex algebra to account for the real and imaginary components of electrical impedance data. The EIT approach provided useful magnitude and phase images for the frequency range of 0.0625 to 64 Hz; images for higher frequencies were not reliable. Comparisons of the � ERT and EIT magnitude images show that both methods provided equivalent results for the water blank, copper rod and PVC rod targets. The EIT magnitude images showed better spatial resolutron for a sand-lead mixture target. Phase images located anomalies of both high and low contrast IP and provided better spatial resolution than the magnitude images. When IP was absent from the data, the EIT algorithm reconstructed phase values consistent with the data noise levels.
Date: December 1, 1998
Creator: Binley, A; Daily, W; LaBredcque, D & Ramirez, A
Partner: UNT Libraries Government Documents Department

Empirical Correlations for Thermal Flowmeters Covering a Wide Range of Thermal-Physical Properties

Description: Thermal flowmeters can provide direct mass flow measurement of gases and vapors over a wide range of process conditions without the need for density corrections based on pressure and temperature. They are widely used in industrial processes that contain toxic, corrosive, or highly reactive gases. It is often not possible to calibrate the flowmeter on the process gas in which it will be used. In this case a non-hazardous �surrogate� gas is used for calibration, and a theoretical model used to predict the meter�s response in the process gas. This can lead to large measurement errors because there are no accurate and straightforward methods for predicting the performance on one kind of gas based on the calibration on another gas because of the complexity of the thermal processes within the flow sensor. This paper describes some of the commonly used models and conversion methods and presents work done at ORNL to develop and experimentally verify better thermal models for predicting flowmeter performance.
Date: July 19, 1999
Creator: Hardy, J.E.; Hylton, J.O. & McKnight, T.E.
Partner: UNT Libraries Government Documents Department

An Instrument for Gravimetric Calibration of Flow Devices with Corrosive Gases

Description: An instrument was developed for the direct mass flow calibration of gas flowmeters that does not require measurement of temperature, pressure, or specific volume. This instrument measures the weight of gas collected in a container and makes measuring those thermodynamic variables unnecessary. The need to measure the weight of the gas container is eliminated by submerging it in a liquid (presently water) and balancing its weight with the force of buoyancy. The accuracy of this Gravimetric Calibrator is unaffected by the pressure and temperature of the gas. The Calibrator can also measure reactive, corrosive, and non-ideal gases. The container remains connected to the process by a torsion capillary, and a load cell measures the changing gas weight continuously throughout the measuring process. A prototype was designed for gas flows ranging from 1 sccm of hydrogen to 10,000 sccm of tungsten hexafluoride, constructed, tested, and used to calibrate flow devices. Experience with the prototype and results are presented, and plans for further developments are discussed.
Date: June 27, 1999
Creator: Hylton, J. O. & Remenyik, C. J.
Partner: UNT Libraries Government Documents Department

Programming Robots with Associative Memories

Description: Today, there are several drawbacks that impede the necessary and much needed use of robot learning techniques in real applications. First, the time needed to achieve the synthesis of any behavior is prohibitive. Second, the robot behavior during the learning phase is � by definition � bad, it may even be dangerous. Third, except within the lazy learning approach, a new behavior implies a new learning phase. We propose in this paper to use self-organizing maps to encode the non explicit model of the robot-world interaction sampled by the lazy memory, and then generate a robot behavior by means of situations to be achieved, i.e., points on the self-organizing maps. Any behavior can instantaneously be synthesized by the definition of a goal situation. Its performance will be minimal (not evidently bad) and will improve by the mere repetition of the behavior.
Date: July 10, 1999
Creator: Touzet, C.
Partner: UNT Libraries Government Documents Department

Data base of array characteristics instrument response and data, recorded at NNC

Description: A northern and east-northern parts of Kazakstan Republic are utterly favorable for a placing of seismic stations. There is a very low level of natural and industrial seismic noise. Rocks of Kazakh epi-Hercynian platform have a very good transmissive properties. Geophysical observatories (GOs), now belonging to the Institute of Geophysical Researches of National Nuclear Center of Kazakstan Republic (IGR NNC RK), were established in especially selected low-noise places of Northern Kazakstan, in accordance with Soviet program for nuclear weapons test monitoring. In 1994, these GOs were transferred by Russian Federation into the possession of Kazakstan. A location of GOs is shown on the Fig. 1. According to the studying of seismic noises, jointly implemented by scientists from IGR and IRIS, places, where a `Borovoye` and `Kurchatov` seismic stations are located, are among the best places for seismic observations in the world. A seismic arrays exist in `Borovoye` and `Kurchatov` observatories - in two observatories out four (`Aktiubinsk`, `Borovoye`, `Kurchatov` and `Makanchi`). These two observatories are described in this report. A history of geophysical observatories, conditions of equipment operations (climatic, geological and so on) are presented in this report, as well as it is described the equipment of GOs and seismic arrays, and samples of digital seismograms, recorded on the equipment of various types, are presented in this report. GO `Borovoye` is described in the 2nd chart, GO `Kurchatov` is described in the 3rd chart of the report. The main results of work are presented in the conclusion. A list of used papers, a list of tables and figures is given in the end of the report. 14 refs., 95 figs., 12 tabs.
Date: December 1, 1996
Creator: Bushueva, E.A.; Ermolenko, E.A. & Efremova, N.A.
Partner: UNT Libraries Government Documents Department

The E781 (SELEX) RICH detector

Description: First results from a new RICH detector, operating in an experiment currently taking data - Fermilab E781 (SELEX), are presented. The detector utilizes a matrix of 2848 phototubes for the photocathode. In a 650 GeV/c ?r- beam the number of photons detected is 14 per ring, giving a Figure of Merit No of 106 cm-`. The ring radius resolution obtained is 1.2 %. Results showing the particle identification ability of the detector are discussed.
Date: June 1, 1997
Creator: Engelfried, J.
Partner: UNT Libraries Government Documents Department

FGI spoolpiece hydrogen sensor response test report

Description: This report documents the results of testing of three flammable gas sensors used on the Rotary Mode Core Sampling System (RMCSS) Flammable Gas Interlock (FGI). These sensors, a Detector Electronics Inc. (Detronics), a Sierra Montiro Corp. (SMC), and a Whittaker Electronics Corp. (WEC) can detect flammable gases and terminate the core sampling activity at a predetermined gas concentration. Testing showed that each of the units can adequately detect a hydrogen gas mixture within a specified time frame and be accurate within manufacturers specifications.
Date: July 1, 1997
Creator: Witwer, K.S.
Partner: UNT Libraries Government Documents Department

Electromagnetic induction moisture measurement system acceptance test report

Description: This document presents the results of the acceptance test for the hardware and software that was developed to operate the ElectroMagnetic Induction (EMI) moisture measurement system to be used for in-tank moisture measurements. This document satisfies EP 4.1, ``Design Verification Requirements``.
Date: October 7, 1996
Creator: Vargo, G.J.
Partner: UNT Libraries Government Documents Department

Work plan for the developmental control of portable SHMS-E+platform

Description: This document describes the Developmental Control process to be used by Dyncorp Fabrication Services and SGN Eurisys Services Corporation - Remote Sensing and Sampling Equipment Engineering (RSSE) in the fabrication of two portable SHMS- E+ Platforms for Lockheed Martin Hanford (TWRS).
Date: June 16, 1997
Creator: Philipp, B.L.
Partner: UNT Libraries Government Documents Department

Manipulator Performance Evaluation Using Fitts' Taping Task

Description: Metaphorically, a teleoperator with master controllers projects the user's arms and hands into a re- mote area, Therefore, human users interact with teleoperators at a more fundamental level than they do with most human-machine systems. Instead of inputting decisions about how the system should func- tion, teleoperator users input the movements they might make if they were truly in the remote area and the remote machine must recreate their trajectories and impedance. This intense human-machine inter- action requires displays and controls more carefully attuned to human motor capabilities than is neces- sary with most systems. It is important for teleoperated manipulators to be able to recreate human trajectories and impedance in real time. One method for assessing manipulator performance is to observe how well a system be- haves while a human user completes human dexterity tasks with it. Fitts' tapping task has been, used many times in the past for this purpose. This report describes such a performance assessment. The International Submarine Engineering (ISE) Autonomous/Teleoperated Operations Manipulator (ATOM) servomanipulator system was evalu- ated using a generic positioning accuracy task. The task is a simple one but has the merits of (1) pro- ducing a performance function estimate rather than a point estimate and (2) being widely used in the past for human and servomanipulator dexterity tests. Results of testing using this task may, therefore, allow comparison with other manipulators, and is generically representative of a broad class of tasks. Results of the testing indicate that the ATOM manipulator is capable of performing the task. Force reflection had a negative impact on task efficiency in these data. This was most likely caused by the high resistance to movement the master controller exhibited with the force reflection engaged. Measurements of exerted forces were not made, so it is not possible to say ...
Date: April 25, 1999
Creator: Draper, J.V.; Jared, B.C. & Noakes, M.W.
Partner: UNT Libraries Government Documents Department

Real-Time Measurement of Vehicle Exhaust Gas Flow

Description: A flow measurement system was developed to measure, in real-time, the exhaust gas flow from vehicies. This new system was based on the vortex shedding principle using ultrasonic detectors for sensing the shed vortices. The flow meter was designed to measure flow over a range of 1 to 366 Ips with an inaccuracy of ~1o/0 of reading. Additionally, the meter was engineered to cause minimal pressure drop (less than 125mm of water), to function in a high temperature environment (up to 650oC) with thermal transients of 15 oC/s, and to have a response time of 0.1 seconds for a 10% to 90!40 step change. The flow meter was also configured to measure hi-directional flow. Several flow meter prototypes were fabricated, tested, and calibrated in air, simulated exhaust gas, and actual exhaust gas. Testing included gas temperatures to 600oC, step response experiments, and flow rates from O to 360 lps in air and exhaust gas. Two prototypes have been tested extensively at NIST and two additional meters have been installed in exhaust gas flow lines for over one year. This new flow meter design has shown to be accurate, durabIe, fast responding, and to have a wide rangeabi~ity.
Date: June 28, 1999
Creator: Hardy, J.E.; Hylton, J.O.; Joy, R.D. & McKnight, T.E.
Partner: UNT Libraries Government Documents Department

W-026, acceptance test report gamma energy assay (GEA) system A(submittal {number_sign}39.8) C3

Description: This test procedure is designed to test all of the functions of the GEA system at the WRAP facility at Hanford, Washington. The procedure is designed to be executed in the sequence given, starting with: * verification of components and labeling * verification or entry of all of the setup parameters * performing the calibrations (energy, efficiency, transmission, and reference peak) * performing the measurements in local mode * performing the measurements in remote mode * confirming the message formats * utility operations (LN2 fill, archiving, password maintenance) The system is designed to be operated in a remote mode in which all commands are received over a network, and the results are returned over the same network. A manual mode is provided for the setup and calibration operations, and for maintenance functions. The system is designed to start up in remote mode. The user can go to local mode when at the keyboard by selecting Exit on the screen shown during remote mode. A user logon screen, requiring 2 username and password, limits access to local mode.
Date: January 28, 1997
Creator: Watson, T.L., Westinghouse Hanford Co., Richland, WA
Partner: UNT Libraries Government Documents Department

Fiber optic inclination detector system

Description: A fiber optic inclination detector system for determining the angular displacement of an object from a reference surface includes a simple mechanical transducer which requires a minimum number of parts and no electrical components. The system employs a single light beam which is split into two light beams and provided to the transducer. Each light beam is amplitude modulated upon reflecting off the transducer to detect inclination. The power values associated with each of the reflected light beams are converted by a pair of photodetectors into voltage signals, and a microprocessor manipulates the voltage signals to provide a measure of the angular displacement between the object and the reference surface.
Date: December 31, 1994
Creator: Cwalinski, J.P.
Partner: UNT Libraries Government Documents Department

Innovative directional and position specific sampling technique

Description: The main objective of UTD`s completed contract was to demonstrate the accuracy UTD POsition LOcator (POLO) system d for penetrometer applications. The contract work was accomplished in three phases. Phase I involved sub-scale refinement of the POLO sub-systems which included the design and testing of individual components of POLO. The objectives of Phase II were to integrate a prototype POLO unit and demonstrate its accuracy through laboratory tracking experiments. Phase III objectives included manufacturing and assembly of a full-scale POLO unit and demonstration of its accuracy under field conditions. The success criterion for the entire contract was to calculate the penetrometer tip position with 0.5% accuracy or better with respect to distance traveled both in laboratory and field tests. This criterion was satisfied in Phase II laboratory tests and in Phase III field tests at two different sites. With successful completion of the contract in September, 1994, UTD has embarked on a commercialization plan in order to make commercial POLO units available to DOE contractors and penetrometer users in a timely fashion.
Date: December 31, 1994
Creator: Foster, E.L.
Partner: UNT Libraries Government Documents Department

Performance results on the laser portion of the Keck laser guide star system

Description: The Laser Guide Star (LGS) system for the Keck II, 10 m telescope consists of two separate but interconnected systems, the laser and the adaptive optics bench. The laser portion of the LGSl is a set of five frequency doubled YAG lasers pumping a master oscillator-power amplifier dye chain to produce up to 30 W of 589 p at 26 kHz of tuned light. Presently the laser system has been set up at the Keck facility in Waimea, HI and is undergoing test and evaluation. When it will be set up on the Keck II telescope, the pump lasers, dye master oscillator and associated control equipment will be located on the dome floor and the dye laser amplifiers, beam control system and diagnostics will be mounted directly on the telescope as shown in Fig. 1, Extensive use of fiber optics for both transmission of the oscillator pulse and the pump laser light has been used.
Date: September 29, 1998
Creator: Cooke, J B; Danforth, P M; Erbert, G V; Feldman, M; Friedman, H W; Gavel, D T et al.
Partner: UNT Libraries Government Documents Department

A Brief Discussion of Radiation Hardening of CMOS Microelectronics

Description: Commercial microchips work well in their intended environments. However, generic microchips will not fimction correctly if exposed to sufficient amounts of ionizing radiation, the kind that satellites encounter in outer space. Modern CMOS circuits must overcome three specific concerns from ionizing radiation: total-dose, single-event, and dose-rate effects. Minority-carrier devices such as bipolar transistors, optical receivers, and solar cells must also deal with recombination-generation centers caused by displacement damage, which are not major concerns for majority-carrier CMOS devices. There are ways to make the chips themselves more resistant to radiation. This extra protection, called radiation hardening, has been called both a science and an art. Radiation hardening requires both changing the designs of the chips and altering the ways that the chips are manufactured.
Date: December 18, 1998
Creator: Myers, D.R.
Partner: UNT Libraries Government Documents Department

Phase 3 Final Topical Report for the Remote Operated Vehicle with C02 Blasting (ROVCO2)

Description: This report documents the third and final phase of the Remote Operated Vehicle with CO2 Blasting (ROVCO2) Program. The Program=s goal is to develop and demonstrate a tool to improve the productivity of concrete floor decontamination. In Phase 3 of the ROVCO2 program, the workhead and the COYOTEE end-effector were redesigned, and effectiveness and productivity tests were performed. This report documents the development activities. The results show that the ROVCO2 system is an efficient decontamination tool, but with relatively slow production rates.
Date: April 14, 1998
Partner: UNT Libraries Government Documents Department

The CMS central hadron calorimeter: Update

Description: The CMS central hadron calorimeter is a brass absorber/ scintillator sampling structure. We describe details of the mechanical and optical structure. We also discuss calibration techniques, and finally the anticipated construction schedule.
Date: June 1, 1998
Creator: Freeman, J.
Partner: UNT Libraries Government Documents Department

New six degree of freedom position sensor greatly improves flexible manufacturing -- but will manufacturers adapt?

Description: The manufacturing industry needs better multi-dimensional position sensors to keep pace with increased speed and capabilities of automated equipment and robots. The market for laser and vision sensors is growing at a rapid speed; however, most of the robot- mounted sensors are one or two dimensional, three dimensional at most, while the robotics industry has progressed to 6-axis machines, leaving a gross mismatch in its capability to perform and sense the required task. A new laser sensor provides information. on up to six degrees of position, enabling robots to sense as well as it can physically manipulate, and opening the door to vast improvements in flexible manufacturing. To expedite these improvements, the manufacturing industry should take a lead and not let an outdated norm hinder implementation.
Date: March 2, 1998
Creator: Vann, C. S., LLNL
Partner: UNT Libraries Government Documents Department

Wavefront control system for the Keck telescope

Description: The laser guide star adaptive optics system currently being developed for the Keck 2 telescope consists of several major subsystems: the optical bench, wavefront control, user interface and supervisory control, and the laser system. The paper describes the design and implementation of the wavefront control subsystem that controls a 349 actuator deformable mirror for high order correction and tip-tilt mirrors for stabilizing the image and laser positions.
Date: March 1, 1998
Creator: Brase, J. M., LLNL
Partner: UNT Libraries Government Documents Department

Large aperture Fresnel telescopes/011

Description: At Livermore we`ve spent the last two years examining an alternative approach towards very large aperture (VLA) telescopes, one based upon transmissive Fresnel lenses rather than on mirrors. Fresnel lenses are attractive for VLA telescopes because they are launchable (lightweight, packagable, and deployable) and because they virtually eliminate the traditional, very tight, surface shape requirements faced by reflecting telescopes. Their (potentially severe) optical drawback, a very narrow spectral bandwidth, can be eliminated by use of a second (much smaller) chromatically-correcting Fresnel element. This enables Fresnel VLA telescopes to provide either single band ({Delta}{lambda}/{lambda} {approximately} 0.1), multiple band, or continuous spectral coverage. Building and fielding such large Fresnel lenses will present a significant challenge, but one which appears, with effort, to be solvable.
Date: July 16, 1998
Creator: Hyde, R.A., LLNL
Partner: UNT Libraries Government Documents Department