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An Ultrasonic Measurement System for The Precise Determination of the Elastic Moduli of Single Crystals

Description: From Abstract: "The equipment described in this paper is based on the technique developed by McSkimin. Figure 1 shows a block diagram of the system. The oscilloscope presentation with no specimen present appears as shown in Figure 2a. At discrete frequencies, the pattern appears as shown in Figure 2b."
Date: May 1961
Creator: Renken, C. J.
Partner: UNT Libraries Government Documents Department

NACA Radio Ground-Speed System for Aircraft

Description: Report presenting a method utilizing the Doppler effect on radio signals for determining the speed and distance traveled of an airplane. The method is called the NACA radio ground-speed system and uses the standard radio transmitter already found in most aircraft. Flight tests were made in which the method was used and the results were consisted with calibrated airspeed indications and stop-watch measurements.
Date: February 1943
Creator: Hastings, Charles E.
Partner: UNT Libraries Government Documents Department

Recommended Practice for the Use of Metric (SI) Units in Building Design and Construction

Description: Report issued by the U.S. National Bureau of Standards discussing the use of metric units of measurement during construction. As stated in the scope, "this document outlines a selection of SI units, with multiples and sub-multiples, for general use in building design and construction" (p. 1). This report includes tables, and illustrations.
Date: April 1977
Creator: Milton, Hans J.
Partner: UNT Libraries Government Documents Department

Descriptive Model of Generic WAMS

Description: The Department of Energy’s (DOE) Transmission Reliability Program is supporting the research, deployment, and demonstration of various wide area measurement system (WAMS) technologies to enhance the reliability of the Nation’s electrical power grid. Pacific Northwest National Laboratory (PNNL) was tasked by the DOE National SCADA Test Bed Program to conduct a study of WAMS security. This report represents achievement of the milestone to develop a generic WAMS model description that will provide a basis for the security analysis planned in the next phase of this study.
Date: June 1, 2007
Creator: Hauer, John F. & DeSteese, John G.
Partner: UNT Libraries Government Documents Department

Installation and Implementation of an In-Process Coordinate Measuring Machine (CMM)

Description: This report documents the work accomplished during the installation and implementation of the in-process Coordinate Measuring Machine (CMM) in Department A. A wealth of knowledge has been gained in solving the many technical issues that delayed the partial implementation of this CMM. The work completed thus far lead to the successfully calibrated in-process CMM workstation. A great deal of current and future work has been outlined in the following pages that shall be used as a guide for the full implementation of this CMM with machining processes in Department A.
Date: June 16, 2008
Creator: Johnston, Derek
Partner: UNT Libraries Government Documents Department

A Measurement System for Monitoring Play in Typically Developing Children and Children with Autism

Description: A comprehensive measurement system was developed to monitor play in children with autism and typically developing children. The study was conducted in a preschool operated in conjunction with a center-based program for children with autism. The development of the measurement system was based on observations of four children with autism and three typically developing children during social and play activites. Data were collected on material use and several dimensions of play: Simple Manipulation, Functional Manipulation, Symbolic Toy Play, Symbolic Role Play and Play Themes. The results indicated that the measurement system consistently measured a wide range of play behaviors across children and materials. Significance of the information gathered from the measurement system in assessing play and designing interventions is discussed.
Date: May 2002
Creator: Gudmundsdottir, Kristin
Partner: UNT Libraries


Description: In the first quarter of the project, we reviewed many past references about using light scattering to characterize particulate matters. We also constructed light sources, detection systems and PM synthesizer for the project.
Date: January 28, 2003
Creator: Wu, Sheng; Palm, Steve; Tang, Yongchun & III, William A. Goddard
Partner: UNT Libraries Government Documents Department

Development of an on-line coal washability analyzer. Semi-annual technical report, September 1, 1996--March 31, 1997

Description: Washability analysis is the basis for nearly all coal preparation plant separations. Unfortunately, there are no on-line techniques for determining this most fundamental of all coal cleaning information. In light of recent successes at the University of Utah, it now appears possible to determine coal washability on-line through the use of x-ray computed tomography (CT) analysis. The successful development of such a device is critical to the establishment of process control and automated coal blending systems. In this regard, Virginia Tech, Terra Tek Inc., and Cyprus-Amax Coal Company have joined with the University of Utah and agreed to undertake the development of an x-ray CT-based on-line coal washability analyzer with financial assistance from DOE. The three-year project will cost $594,571, of which 33% ($194,575) will be cost-shared by the participants. The project will involve development of appropriate software and extensive testing/evaluation of well- characterized coal samples from three coal preparation plants. Each project participant brings special expertise to the project which is expected to create a new dimension in coal cleaning technology. Finally, it should be noted that the analyzer may prove to be a universal analyzer capable of providing not only washability analysis, but also particle size distribution analysis, ash analysis and perhaps pyritic sulfur analysis.
Date: March 31, 1997
Creator: Miller, J.D.; Lin, C.L.; Luttrell, G.H.; Adel, G.T.; Owen, L.B. & Fish, L.
Partner: UNT Libraries Government Documents Department

Experimental measurements of the thermal conductivity of ash deposits: Part 1. Measurement technique

Description: This paper describes a technique developed to make in situ, time-resolved measurements of the effective thermal conductivity of ash deposits formed under conditions that closely replicate those found in the convective pass of a commercial boiler. Since ash deposit thermal conductivity is thought to be strongly dependent on deposit microstructure, the technique is designed to minimize the disturbance of the natural deposit microstructure. Traditional techniques for measuring deposit thermal conductivity generally do not preserve the sample microstructure. Experiments are described that demonstrate the technique, quantify experimental uncertainty, and determine the thermal conductivity of highly porous, unsintered deposits. The average measured conductivity of loose, unsintered deposits is 0.14 {+-} 0.03 W/(m K), approximately midway between rational theoretical limits for deposit thermal conductivity.
Date: April 1, 2000
Creator: Robinson, A. L.; Buckley, S. G.; Yang, N. & Baxter, L. L.
Partner: UNT Libraries Government Documents Department

In-line ultrasonic monitoring of waste slurry suspended solids

Description: During the transport of tank waste, it is very important to quantitatively measure the percent solids concentration (PSC) of the waste, which indicates the flow conditions and the extent of solids settling. At Argonne National Laboratory, an in-line, real-time, a nonintrusive ultrasonic monitoring system has been developed to measure the PSC and flow density of tank waste by measuring sound velocity and attenuation in the flow. This system consists of a pair of longitudinal transducers bonded to waveguides on the opposite sides of the pipe and operating at IMHz simultaneously in pulse-and-echo and pitch-and-catch modes. The PSC measurement is provided by attenuation, while the density measurement is calculated by impedance and sound velocity. A thermocouple is attached to one of the waveguides for automatic temperature correction of the measurements. This system was one of four evaluated for in-line measurement of slurry at Oak Ridge National Laboratory in 1998. The results indicate that the measurements are in good agreement with a Coriolis meter and that the system can be used to monitor PSC up to 40 wt.%. However, the system is greatly affected by entrained air bubbles within the solid flow during Puisair mixing. A different mixing mechanism will solve this problem.
Date: May 25, 2000
Creator: Chien, H.-T.; Sheen, S.-H. & Raptis, A. C.
Partner: UNT Libraries Government Documents Department

Investigations of chemical vapor deposition of GaN using synchrotron radiation

Description: The authors apply synchrotron x-ray analysis techniques to probe the surface structure of GaN films during synthesis by metal-organic chemical vapor deposition (MOCVD). Their approach is to observe the evolution of surface structure and morphology in real time using grazing incidence x-ray scattering (GIXS). This technique combines the ability of x-rays to penetrate the chemical vapor deposition environment for in situ measurements, with the sensitivity of GIXS to atomic scale structure. In this paper they present examples from some of their studies of growth modes and surface evolution as a function of process conditions that illustrate the capabilities of synchrotron x-ray analysis during MOCVD growth. They focus on studies of the homoepitaxial growth mode, island coarsening dynamics, and effects of impurities.
Date: May 25, 2000
Creator: Thompson, C.; Stephenson, G. B.; Eastman, J. A.; Munkholm, A.; Auciello, O.; Murty, M. V. R. et al.
Partner: UNT Libraries Government Documents Department

Two Applications of Direct Digital Down Converters in Beam Diagnostics

Description: The technologies of direct digital down converters, digital frequency synthesis, and digital signal processing are being used in many commercial applications. Because of this commercialization, the component costs are being reduced to the point where they are economically viable for large scale accelerator applications. This paper will discuss two applications of these technologies to beam diagnostics. In the first application the combination of direct digital frequency synthesis and direct digital down converters are coupled with digital signal processor technology in order to maintain the stable gain environment required for a multi-electrode beam position monitoring system. This is done by injecting a CW reference signal into the electronics as part of the front-end circuitry. In the second application direct digital down converters are used to provide a novel approach to the measurement of beam intensity using cavity current monitors. In this system a pair of reference signals are injected into the cavity through an auxiliary port. The beam current is then calculated as the ratio of the beam signal divided by the average of the magnitude of the two reference signals.
Date: May 1, 2000
Creator: Powers, Tom; Flood, Roger; Hovater, Curt & Musson, John
Partner: UNT Libraries Government Documents Department

The Role of Standard Reference Materials in Measurement Systems

Description: Report is a guide to Standard Reference Materials (SRM's) and should be useful to all users of SRM's particularly those in countries developing national measurement systems. It is not intended to be an exhaustive description of the NBS-SRM program, but rather a review of the role SRM's play in the measurement system, how SRM's are certified, and what the certification means. To illustrate the use of SRM's, several selected industries are described in which SRM's have made significant contributions.
Date: January 1975
Creator: Cali, J. P.; Mears, T. W.; Michaelis, R. E.; Reed, W. P.; Seward, R. W.; Stanley, C., L. et al.
Partner: UNT Libraries Government Documents Department

On-Machine Acceptance

Description: Probing processes are used intermittently and not effectively as an on-line measurement device. This project was needed to evolve machine probing from merely a setup aid to an on-the-machine inspection system. Use of probing for on-machine inspection would significantly decrease cycle time by elimination of the need for first-piece inspection (at a remote location). Federal Manufacturing and Technologies (FM and T) had the manufacturing facility and the ability to integrate the system into production. The Contractor had a system that could optimize the machine tool to compensate for thermal growth and related error.
Date: February 14, 2000
Creator: Arnold, K.F.
Partner: UNT Libraries Government Documents Department

Electrical signature analysis (ESA) developments at the Oak Ridge Diagnostics Applied Research Center

Description: Since 1985, researchers at the Oak Ridge National Laboratory (ORNL) have developed and patented several novel signal conditioning and signature analysis methods that have exploited the intrinsic abilities of conventional electric motors and generators to act as transducers. By using simple nonintrusive sensors such as clamp-on current and voltage probes, these new diagnostic techniques provide an improved means of detecting small time-dependent load and speed variations generated anywhere within an electromechanical system and converting them into revealing signatures that can be used to detect equipment degradation and incipient failures. These developments have been grouped under the general name of electrical signature analysis (ESA) and together provide a breakthrough in the ability to detect, analyze, and correct unwanted changes in process conditions or the presence of abnormalities in electrical and electromechanical equipment. Typical diagnostic information provided by ESA is comparable to that provided by conventional vibration analysis in that both time waveform and frequency spectrum signatures may be produced. The primary benefit of ESA is that an extensive range of diagnostic information can be obtained from a single transducer that may be installed several hundred feet or more from the monitored device on its electrical lines supplying input power (e.g., to a motor) or carrying output power (e.g., from a generator); thus, ESA is truly remote and nonintrusive.
Date: July 1, 1995
Creator: Haynes, H.D.
Partner: UNT Libraries Government Documents Department

Online monitoring in the upcoming Fermilab Tevatron Run II

Description: We describe the online event monitoring systems using ROOT [1] for the CDF and D0 collaborations in the upcoming Fermilab Tevatron runII. The CDF and D0 experiments consist of many detector subsystems and will run in a high rate large bandwidth data transfer environment. In the experiments, it is crucial to monitor the performance of each subsystem and the integrity of the data, in real time with minimal interruption. ROOT is used as the main analysis tool for the monitoring systems and its GUI is used to browse the results via socket, allowing multiple GUI client connections.
Date: September 8, 1999
Creator: Canal, P.; Kowalkowski, J.; Maeshima, K.; Yu, J.; Wenzel, H.; Snow, J. et al.
Partner: UNT Libraries Government Documents Department


Description: In the fourth quarter of the project, we fixed the interference problem of linear CCD array when collecting elastic scattering signal from laser sources. We collected scattering signal of standard samples and also on a wax formation liquid. The results are compared to theoretical results and demonstrate the clear advantages of such technique vs. traditional scattering instrument with enclosures or just transmission type of spectrometers.
Date: October 31, 2003
Creator: Wu, Sheng; Palm, Steve; Tang, Yongchun & III, William A. Goddard
Partner: UNT Libraries Government Documents Department

Assuring Mechanical Integrity of Refinery Equipment Through Global ON-Stream Inspection

Description: The development of global on-stream inspection technology will have a dramatic effect on how refinery operations are managed in the U.S. in the future. Global on-stream inspection will provide assurance of the mechanical integrity of critical plant equipment and will allow refineries to operate more efficiently with less impact on our environment and with an increased margin of safety.
Date: February 22, 2006
Creator: Berthold, John W.
Partner: UNT Libraries Government Documents Department

Fiber Optical Micro-detectors for Oxygen Sensing in Power Plants

Description: A reflection mode fiber optic oxygen sensor that can operate at high temperatures for power plant applications is being developed. The sensor is based on the {sup 3}O{sub 2} quenching of the red emission from hexanuclear molybdenum chloride clusters. Previously we described a particle-in-binder approach to immobilizing the potassium salt of the molybdenum cluster, K{sub 2}Mo{sub 6}Cl{sub 14}, at the tips of optical fibers. Compared to previous methods, the particle-in-binder approach affords fibers with greatly improved mechanical properties. The response of the sensor to oxygen at 40, 70 and 100 C was measured in 2-21% gas phase oxygen. The normalized sensor signal is linear with molar oxygen concentration and fits the theoretical Stern-Volmer relationship. Although the sensitivity decreases with temperature, at 100 C the sensitivity is 160 [O{sub 2}]{sup -1}. These are promising results for a high temperature fiber optical oxygen sensor based on molybdenum chloride clusters.
Date: May 1, 2006
Creator: Baker, Gregory L.; Ghosh, Ruby N.; III, D.J. Osborn & Zhang, Po
Partner: UNT Libraries Government Documents Department