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Tests of Commercial Densimeters for LNG Service
Abstract: Densimeters for liquefied natural gas (LNG) from four manufacturers were tested in liquid methane and an LNG-like mixture of methane, propane, and nitrogen in the density reference system (DRS). The calibration and performance of one type tested for the first time are reported. The stability of the calibrations and performances of three densimeters of a type previously tested have been examined and are also reported here.
Date:
June 1982
Creator:
Siegwarth, J. D. & LaBrecque, J. F.
Object Type:
Report
System:
The UNT Digital Library
Tests of Large Columns with H-Shaped Sections
Report issued by the Bureau of Standards over studies conducted on h-shaped columns. Physical and chemical tests were conducted on different types of columns. The results are presented and discussed. This report includes tables, illustrations, and photographs.
Date:
June 11, 1926
Creator:
Tuckerman, L. B. & Stang, A. H.
Object Type:
Report
System:
The UNT Digital Library
Theory and Application of Expert Systems in Emergency Management Operations
Abstract: The First Symposium on The Theory and Application of Expert Systems in Emergency Management, held at the Department of Commerce, Washington, D.C. (April 24 and 25, 1985) was funded by the Federal Emergency Management Agency and organized by the National Bureau of Standards' Operations Research Division. The purpose of the symposium was to bring together researchers in expert systems, artificial intelligence, and emergency operations in a forum to review the concepts of expert systems and the problems of emergency management, with the objective of determining how expert systems can be used to augment the experience of local, State and Federal emergency managers faced with the difficult tasks of determining the best response to an emergency situation. Speakers addressed the following areas: The theory and uncertainty aspects of expert systems, artificial intelligence's future role in emergency management, technology for building and using expert systems, emergency management decisions and information needs and uses, applications of expert systems in the management of chemical spills and shipboard and coal mine fires, and the role and use of simulation in emergency management expert systems.
Date:
November 1986
Creator:
Gass, Saul I. & Chapman, Robert E.
Object Type:
Report
System:
The UNT Digital Library
Theory and Methods of Optical Pyrometry
Report reviewing the theoretical methods of optical pyrometry and the application of these methods at the National Bureau of Standards in realizing, maintaining and distributing the International Practical Temperature Scale above 1063 ºC is presented. In the theoretical presentation, the concepts of effective and mean effective wavelengths are introduced, and various equations relating these parameters to each other and other physical quantities are derived. The methods presentation discusses important features of precision visual optical pyrometers, experimental procedures, and results of primary and secondary calibrations of optical pyrometers.
Date:
March 1, 1962
Creator:
Kostkowski, H. J. & Lee, R. D.
Object Type:
Report
System:
The UNT Digital Library
Theory of Determination of Ultra-Radio Frequencies by Standing Waves on Wires
Scientific paper issued by the Bureau of Standards over ultra-radio frequencies. As stated in the abstract, "this paper furnishes the theoretical background for the method of frequency standardization employing short standing waves on parallel wires" (p. 487). This paper includes tables, and illustrations.
Date:
June 23, 1924
Creator:
Hund, August
Object Type:
Report
System:
The UNT Digital Library
A Theory of Mutual Impedances and Multiple Reflections in an N-Element Array Environment
Abstract: A general theoretical approach is formulated to describe the complex electromagnetic environment of an N-element array. The theory reveals the element-to-element interactions and multiple reflections within the array. From the formulation, it is found that the interaction between an excited element and an open-circuited element can be viewed as the sum of terms describing all possible signal paths within the array environment which start from the radiating element and terminate on the element under observation. Within all paths except the most direct one, multiple reflections between subgroups of elements take place. The resulting solution is highly structured and recursive and is discussed in detail in the text. Illustrative examples are provided to facilitate understanding of these ideas.
Date:
February 1985
Creator:
Muth, Lorant A.
Object Type:
Report
System:
The UNT Digital Library
Theory of Near-Field Phased Arrays for Electromagnetic Susceptibility Testing
From introduction: The feasibility of using a near-field array for electromagnetic susceptibility testing is studied. The basic objective is to control the element weightings such that a plane wave is generated within the test volume. The basic theory is developed for arbitrary array geometries, and numerical results are obtained for finite planar arrays. A general near-field array synthesis technique is developed, and the technique minimizes the mean square error in the test volume while constraining the array excitations. The constraint prevents large excitations and is useful in minimizing the fields outside the test volume. The basic idea looks promising, but some practical considerations, such as bandwidth and angular scanning limitations, require further theoretical and experimental investigation.
Date:
February 1984
Creator:
Hill, D. A.
Object Type:
Report
System:
The UNT Digital Library
The Theory of the Optical Wedge Beam Splitter
Report discussing optical wedge beam splitters and the basic theory for computing the ratio of the intensity of the incident beam to the intensity of any selected emerging beam and also for computing the direction of the emerging beam, assuming that the wedge angle, index of refraction, angle of incidence, and number of reflections are known.
Date:
October 1974
Creator:
Beers, Yardley
Object Type:
Report
System:
The UNT Digital Library
Thermal Behavior of Fine-Grained Soils
Report issued by the National Bureau of Standards over thermal tests conducted on soil samples. The results of the laboratory tests are discussed. This report includes tables, illustrations, photographs.
Date:
November 1982
Creator:
Salomone, Lawrence A.; Kovacs, William D. & Wechsler, Herbert
Object Type:
Report
System:
The UNT Digital Library
Thermal Conductivity of Solids At Room Temperature and Below: A Review and Compilation of the Literature
From Abstract: "An extensive compilation is given of the measured values of thermal conductivity for nearly all solid materials from room temperature down to 0.02 kelvin. Experimental methods and physical phenomena are discussed in the text and coded in the tables for references for which curves are shown."
Date:
September 1973
Creator:
Childs, Gregg E.; Ericks, Lewis J. & Powell, Robert L.
Object Type:
Report
System:
The UNT Digital Library
Thermal Expansion of Insulating Materials
Scientific paper issued by the Bureau of Standards over studies on thermal expansion. Expansivity tests are conducted on many different insulating materials. The results of the tests are discussed. This paper includes tables, photographs, and illustrations.
Date:
December 27, 1919
Creator:
Souder, Wilmer H. & Hidnert, Peter
Object Type:
Report
System:
The UNT Digital Library
Thermal Expansion of Technical Solids at Low Temperatures: A Compilation From the Literature
Report giving tables of the linear contraction relative to 293 ºK, (L293ºLT)/L293, and the linear expansion coefficient, dL/L293dT, of thirty elements, forty-five alloys, twenty-two other inorganic substances and twenty plastics and elastomers in the temperature range, 0 to 300 ºK.
Date:
May 19, 1961
Creator:
Corruccini, Robert J. & Gniewek, John J.
Object Type:
Report
System:
The UNT Digital Library
Thermocouple Materials
From Introduction: "The purpose of this paper is to present information on materials that are used from 0 degrees C up in thermocouples intended primarily as immersed temperature sensors, and to give so far as is practical properties of these materials that might affect their use in temperature measurement."
Date:
March 1, 1962
Creator:
Caldwell, F. R.
Object Type:
Report
System:
The UNT Digital Library
Thermocouple Reference Tables Based on the IPTS-68
From Abstract: "Revised reference data for thermocouples have been generated in a cooperative program between groups of the National Bureau of Standards in Boulder and Gaithersburg.This Monograph contains tables, analytic expressions, various approximations, and explanatory text.
Date:
March 1974
Creator:
Powell, Robert L.; Hall, William J.; Hyink, Clyde H., Jr.; Sparks, Larry L.; Burns, George W.; Scroger, Margaret G. et al.
Object Type:
Report
System:
The UNT Digital Library
Thermocouple Reference Tables Based on the IPTS-68: Reference Tables in Degrees Fahrenheit for Thermoelements versus Platinum (Pt-67)
Report presenting tables as a supplement to those given in NBS Monograph 125. Tables were calculated from the power series expansions presented in that Monograph. They are based upon the absolute electrical units and the International Practical Temperature Scale of 1968 (IPTS-68). Reference tables for several thermoelements versus platinum (Pt-67) are given with values of the thermoelectric voltage as a function of temperature in degrees Fahrenheit. Only tables for standard letter-designated thermoelements are included.
Date:
March 1975
Creator:
Powell, Robert L. & Burns, George W.
Object Type:
Report
System:
The UNT Digital Library
Thermodynamic and Related Properties of Parahydrogen From the Triple Point to 100 K at Pressures to 340 Atmospheres
From Introduction: "In the present report, therefore, polynomials representing isotherms and isochores are combined with numerical methods of computation for the purpose of improving accuracy, in particular for the derivatives of the P-p-T surface."
Date:
August 10, 1965
Creator:
Roder, H. M.; Weber, L. A. & Goodwin, R. D.
Object Type:
Report
System:
The UNT Digital Library
Thermoelectric Measurement of Critical Ranges of Pure Iron
Report issued by the Bureau of Standards over the measurements of critical ranges of pure iron wire. The methods and materials used for the measurements are discussed. This report includes tables, and illustrations.
Date:
1918
Creator:
Burgess, George K. & Scott, H.
Object Type:
Report
System:
The UNT Digital Library
Thermophysical Properties of Isobutane from 114 to 700 K at Pressures to 70 MPa
Abstract: Using a modified version of the nonanalytic equation of state, thermophysical properties of isobutane are derived from physical properties data and are tabulated at integral temperatures over the entire range of fluid states from 114 to 700 K along isobars at pressures to 70 MPa. Results include dielectric constants, densities, enthalpies, entropies, equation of state, internal energies, isobars, isochores, isotherms, Joule-Thomson inversion, heats of vaporization, melting line, orthobaric densities, specific heats, sound velocities, vapor pressures, and virial coefficients. In addition to the equation of state, equations are given for vapor pressures, orthobaric vapor and liquid densities, ideal gas properties, second virial coefficients, dielectric constants, heats of vaporization, melting pressures, and orthobaric liquid specific heats, enthalpies, and entropies. Several new sets of data have been used in this correlation; comparisons between experimental and calculated values are given.
Date:
January 1982
Creator:
Goodwin, Robert D. & Haynes, William M.
Object Type:
Report
System:
The UNT Digital Library
Time and Frequency: Theory and Fundamentals
From Abstract: "This is a tutorial Monograph describing various aspects of time and frequency (T/F). Included are chapters relating to elemental concepts of precise time and frequency; basic principles of quartz oscillators and atomic frequency standards; historical review, recent progress, and current status of atomic frequency standards; promising areas for developing future primary frequency standards; relevance of frequency standards to other areas of metrology including a unified standard concept; statistics of T/F data analysis coupled with the theory and construction of the NBS atomic time scale; an overview of T/F dissemination techniques; and the standards of T/F in the USA. The Monograph addresses both the specialist in the field as well as those desiring basic information about time and frequency."
Date:
May 1974
Creator:
Blair, Byron E.
Object Type:
Report
System:
The UNT Digital Library
Toluol Recovery
Technical paper issued by the Bureau of Standards over toluol-recovery, known as light oil. The methods used in the toluol-recovery are presented and discussed. This paper includes tables, and illustrations.
Date:
December 19, 1918
Creator:
McBride, R. S.; Reinicker, C. E. & Dunkley, W. A.
Object Type:
Report
System:
The UNT Digital Library
Towards a Tribology Information System
Abstract: A workshop was held in July 985 to address the needs for a computerized tribology information and data system, as well as possible implementation schemes. The meeting was sponsored by the American Society of Mechanical Engineers, Research Committee on Tribology, the Department of Energy, Energy Conservation and Utililation Technology Division, and the National Bureau of Standards. The views of a broad sector of industry, academia, and government were obtained over a four-week period through participation by about 60 individuals. Specific categories that were treated were design, numeric data, bibliography, research in progress, newsletter, and product directory. The principal discussion content and the recommendations in each subject category are summarized here. There was general agreement that a system of this type would be broadly useful to the engineering community for the purpose of design and materials selection, and for the research community as an important aid in information access and flow. The workshop recommendations detailed four phases of development, starting with a demonstration prototype system and concluding with a full-scale operating data and information base. Specific plans in each phase and for each subject area were developed and are presented here. While continual input will be sought from the technical …
Date:
December 1987
Creator:
Rumble, John R., Jr. & Sibley, Lewis
Object Type:
Report
System:
The UNT Digital Library
Trace Characterization: Chemical and Physical
From Introduction: "This symposium focuses attention on the growing awareness of the necessity for developing and using better methods for characterizing solids. Many of the most interesting properties of solids depend directly upon these small concentrations of impurities and defects, and the illustration of this is a principal theme of this paper."
Date:
April 28, 1967
Creator:
Meinke, W. Wayne & Scribner, Bourdon F.
Object Type:
Report
System:
The UNT Digital Library
Transparent Metrology of Signal to Noise Ratios of Noisy Band-Limited Digital Signals
From abstract: I propose the use of a template method for quantitative, correct, and transparent measurement of signal power to additive noise power ratios (SNR) of digital signals and systems under full operating conditions. Outer guard chips of digital templates hold intersymbol interference fixed on inner target chips in realizations of the respective template patterns in traffic. The proposed template method needs to be developed and proven as a potentially valuable metrology capability; it can be especially important for real time online performance assessment and monitoring of digital communication systems.
Date:
June 1985
Creator:
Halford, Donald
Object Type:
Report
System:
The UNT Digital Library
Trapped Ions and Laser Cooling: Selected Publications of the Ion Storage Group of the Time and Frequency Division, NBS, Boulder, Colorado
Abstract: Selected publications of the Ion Storage Group of the Time and Frequency Division, NBS, Boulder, Colorado.
Date:
July 1985
Creator:
Wineland, David J.; Itano, Wayne M.; Bergquist, James Charles & Bollinger, John J.
Object Type:
Report
System:
The UNT Digital Library