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Automatic Indexing: A State-of-the-Art Report

Description: Report issued by the U.S. National Bureau of Standards discussing results of a survey conducted on automatic mechanized indexing and data processing. As stated in the introduction, "it has concentrated on the major developments in and related demonstrations of automatic indexing potentialities. Examples are also given of indexes compiled by machine and of potentially related research efforts in such areas as natural language text searching, statistical association techniques used for search and retrieval, and proposed systems for concept processing" (p. 1). This report includes an illustration.
Date: February 1970
Creator: Stevens, Mary Elizabeth
Partner: UNT Libraries Government Documents Department

Geometrical Considerations and Nomenclature for Reflectance

Description: Report issued by the U.S. National Bureau of Standards discussing specifications of reflectance and proposed nomenclature. As stated in the introduction, "this monograph presents a unified approach to the specification of reflectance in relation to the beam geometry of both the incident and the reflected flux in any reflectometer or in any application of measured reflectance data" (p. 1). This report includes illustrations.
Date: October 1977
Creator: Nicodemus, F. E.; Richmond, J. C.; Hsia, J. J.; Ginsberg, I. W. & Limperis, T.
Partner: UNT Libraries Government Documents Department

Mass and Mass Values

Description: Report discussing the different bases for determining mass values and instances where these differences may be crucial. The first part is a historical summary of weighing, standards, and the assignment of value; and the interfacing of mass measurements with civilization. The second part discusses in detail the methods of assigning mass values. Ways to convert from values on one basis to values on another basis are discussed.
Date: January 1974
Creator: Pontius, Paul E.
Partner: UNT Libraries Government Documents Department

Properties of Glasses in Some Ternary Systems Containing BaO and SiO2

Description: Report discussing the glass forming regions in six ternary oxide systems containing BaO, Si02, and a third oxide. The properties of the resulting glasses were measured and the results reported. The data on refractive indices, dispersions, and specific volumes were evaluated by computer methods in an attempt to identify "substructures" containing the cations present in the glasses.
Date: September 1973
Creator: Cleek, Given W. & Babcock, C. L.
Partner: UNT Libraries Government Documents Department

The Theory of the Optical Wedge Beam Splitter

Description: 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
Partner: UNT Libraries Government Documents Department

A Gage Block Measurement Process Using Single Wavelength Interferometry

Description: Report describing the interferometric measurement process using a laser light source and a Kosters type gage block interferometer. Continuous evaluation and refinement of the process is aided by statistical treatment and control chart techniques. All error sources, both random and systematic, are evaluated and the process is maintained in a state of statistical control.
Date: December 1975
Creator: Beers, John S.
Partner: UNT Libraries Government Documents Department

The First Spectrum of Hafnium (HF I)

Description: Report continuing W. K. Meggers' previous analysis in LS-coupling. This coupling is not rigorous in Hf I, and many intervals are irregular. Consequently, the levels are given also in numerical order with the even and odd levels presented in separate tables. The long line lists are given in two Appendices: Appendix A contains the observed Zeeman data for the individual lines, 531 in all; Appendix B consists of the complete line list of observed and classified lines. By far the greater part of the analysis is that of Meggers.
Date: July 1976
Creator: Meggers, William F. & Moore, Charlotte E.
Partner: UNT Libraries Government Documents Department

The Dynamics of Fields of Higher Spin

Description: Report presenting a relativistic theory of motion that is free of many of the difficulties common in relativistic equations of motion. This Lagrangian theory describes fields and particles with arbitrary mass and charge and having any discrete spin, integer or half integer.
Date: August 1976
Creator: Hayward, Raymond W.
Partner: UNT Libraries Government Documents Department

Relativistic Many-Body Bound Systems: Electromagnetic Properties

Description: Report presenting the formulae for the calculation of the electron scattering form factors, and of the static magnetic dipole and electric quadrupole moments, of relativistic many-body bound systems. The framework, given in NBS Monograph 147, is relativistic quantum field theory in the Schrodinger picture ; the physical particles, i.e. the solutions of the interacting fields, are given as linear combinations of the solutions of the free fields, called the parton fields. The parton-photon interaction is taken as given by minimal coupling, p -> p - eA ; in addition the contribution of the photon-vector meson vertex of the vector dominance model is derived.
Date: April 1977
Creator: Danos, Michael & Gillet, Vincent
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

Liquid-in-Glass Thermometry

Description: Report containing information of general interest to manufacturers and users of liquid-in-glass thermometers. This report supersedes Monograph 90. Instructions explaining how to submit a thermometer to the National Bureau of Standards for calibration are provided, and the techniques and equipment, such as stirred liquid comparison baths, used in the calibration procedures are described. A discussion of important principles of acceptable thermometer design and factors affecting their use is included. Listed are tables of tolerances reflecting good manufacturing practices and reasonably attainable accuracies expected with liquid-in-glass thermometers. The calculation of corrections for the temperature of the emergent stem is given in detail for various types of thermometers and conditions of use.
Date: January 1976
Creator: Wise, Jacquelyn A.
Partner: UNT Libraries Government Documents Department

Graphical Recoupling of Angular Momenta

Description: Report presenting a diagrammatic method for solving angular momentum recoupling problems. It is shown that a few graphical elements with a set of rules for their use lead to the solution of many types of recoupling problems in an intuitive and systematic way. Several examples are given together with exercises to develop the reader's facility with the method.
Date: October 1973
Creator: Lehman, D. R. & O'Connell, J. S.
Partner: UNT Libraries Government Documents Department

Interactions of High Energy Particles With Nuclei

Description: Report discussing elastic scattering and diffractive production processes induced in nuclear targets by high energy projectiles. Special attention is paid to the interaction of high energy hadrons and photons. The common features of all these processes are emphasized throughout the article: The multiple scattering and shadowing processes inside of the target nuclei. An effort is made to develop a unified way of treating nuclear interactions of particles which are either hadrons or exhibit some hadronic components in such interactions.
Date: September 1975
Creator: Czyz, Wieslaw
Partner: UNT Libraries Government Documents Department

Analysis of Optically Excited Mercury Molecules

Description: Report presenting new measurement techniques used to obtain potential curves, f-values, and kinetic behavior for Hg2. The Hg2 molecule is representative of a class of molecules which have dissociative ground states and bound excited states. It can therefore be used as a prototype of this class of molecules which are of interest as potential new laser candidates. Because of the non-bound ground state, standard absorption spectroscopic techniques cannot be used to obtain the necessary information about the excited states.
Date: January 1975
Creator: Drullinger, R. E.; Hessel, M. M. & Smith, E. W.
Partner: UNT Libraries Government Documents Department

The Effect of Time Ordering on the Lyman α Profile

Description: Report investigating the effects of time-ordering over the complete line profile using a unified theory of spectral line broadening previously developed. The behavior of the time-ordered thermal average and un-time-ordered thermal average are compared. The Fourier transform of the thermal average is obtained analytically. Calculations for the line profile of the Lyman-[functional symbol alpha] line of hydrogen are presented and are representative in that the full thermal average is replaced by the thermal average with the electron velocity distribution approximated by f(v)=[functional symbol alpha] (v-vav) where vav is the thermal velocity for the plasma in question.
Date: June 1971
Creator: Godgrey, J. T.; Vidal, C. R.; Smith, E. W. & Cooper, J.
Partner: UNT Libraries Government Documents Department

Reference Tables for Low-Temperature Thermocouples

Description: Report discussing the completed experimental program of the low-temperature reference tables for the commonly used thermocouples. Details of the experimental system, instrumentation, data analysis, error analysis, and materials tested are given in order to allow the user to better evaluate and apply the results.
Date: June 1972
Creator: Sparks, Larry L.; Powell, Robert L. & Hall, William J.
Partner: UNT Libraries Government Documents Department

Thermocouple Reference Tables Based on the IPTS-68: Reference Tables in Degrees Fahrenheit for Thermoelements versus Platinum (Pt-67)

Description: 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.
Partner: UNT Libraries Government Documents Department

A High-Dispersion Spectral Analysis of the Ba II Star HD 204075 (ζ Capricorni)

Description: Report discussing a double differential curve of growth analysis for the Ba II star S Capricorni. Both the sun and � Virginis (G9 II-III) were used as comparison stars. The observational material consists of equivalent widths, central depths, and half-widths for 1100 spectral lines measured on direct-intensity tracings of plates obtained by J. L. Greenstein at the coude focus of the 200-in telescope. The plates cover the spectral regions 3880-4825 A and 5100-6720 A at reciprocal dispersions of 2.3 and 3.4 A/mm, respectively. Atmospheric abundances have been derived for 37 elements.
Date: March 1971
Creator: Tech, Jack L.
Partner: UNT Libraries Government Documents Department

Unified Theory Calculations of Stark Broadened Hydrogen Lines Including Lower State Interactions

Description: Report on calculations of hydrogen Stark broadening on the basis of the unified classical path theory which has been extended to include lower state interactions in the final line profile. A detailed comparison with experiments in the density range 10-13-10-17 cm-3 is given.
Date: January 1971
Creator: Vidal, C. R.; Cooper, J. & Smith, E. W.
Partner: UNT Libraries Government Documents Department

The Calculation of Rotational Energy Levels and Rotational Line Intensities in Diatomic Molecules

Description: Report describing procedures for making quantum mechanical calculations of rotational energy levels and rotational line intensities in diatomic molecules. The procedures are illustrated by sample calculations. A familiarity with the material of this report should enable a practicing electronic spectroscropist to carry out, though in a rather mechanical way, his own theoretical calculations for molecules under experimental investigation.
Date: June 1970
Creator: Hougen, Jon T.
Partner: UNT Libraries Government Documents Department

Hydrogen Stark Broadening Calculations With the Unified Classical Path Theory

Description: Report discussing the case of upper and lower state interaction introduced by a unified theory using a more compact tetradic notation. The general result is then applied to the Stark broadening of hydrogen. The thermal average of the time development operator for upper and lower state interaction is presented. A simple technique for evaluating the Fourier transform of the thermal average has been developed. The final calculations based on the unified theory and on the one-electron theory are compared with measurements in the high and low electron density regime.
Date: May 1970
Creator: Vidal, C. R.; Cooper, J. & Smith, E. W.
Partner: UNT Libraries Government Documents Department

Photonuclear Reactions

Description: Report discussing photonuclear reactions in the approximate energy range 10 to 30 MeV. Various sum rules are discussed and applied to experimental data. Several different theories are described and their predictions compared with experiment, and as often as possible open questions and discrepancies are pointed out.
Date: August 1970
Creator: Hayward, Evans
Partner: UNT Libraries Government Documents Department