Technical Report Archive and Image Library (TRAIL) - 13 Matching Results

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

Description: Report presenting a state-of-the-art survey of automatic indexing systems and experiments. It was conducted by the Research Information Center and Advisory Service on Information Processing, Information Technology Division, Institute for Applied Technology, National Bureau of Standards. Consideration is first given to indexes compiled by or with the aid of machines, including citation indexes. Advantages, disadvantages, and possibilities for modification and improvement are discussed. Experiments in automatic assignment indexing are summarized. Related research efforts in such areas as automatic classification and categorization, computer use of thesauri, statistical association techniques, and linguistic data processing are described. A major question is that of evaluation, particularly in view of evidence of human inter-indexer inconsistency. It is concluded that indexes based on words extracted from text are practical for many purposes today.
Date: March 30, 1965
Creator: Stevens, Mary Elizabeth
Partner: UNT Libraries Government Documents Department

Calibration of Liquid-in-Glass Thermometers

Description: Report discussing important elements of thermometer design. Factors affecting the use of common types of liquid-in-glass thermometers are included together with tables of tolerances and reasonably attainable accuracies. 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: February 12, 1965
Creator: Swindells, James F.
Partner: UNT Libraries Government Documents Department

Ionospheric Radio Propagation

Description: From Preface: "The purpose of this book is to replace, in part, a previous publication of the National Bureau of Standards (Circular 462) with the same title. The scope of the present work has therefore been broadened to include aspects of ionospheric radio propagation which were not treated in earlier publication."
Date: April 1, 1965
Creator: Davies, Kenneth
Partner: UNT Libraries Government Documents Department

Microwave Impedance Measurements and Standards

Description: Report presenting a survey and discussion of well-known microwave impedance measurement techniques. The discussion includes an introduction which emphasizes basic concepts and reflection coefficient-voltage standing-wave ratio relationships. Sources of error in the various measurement techniques are discussed and methods to reduce errors are presented. Methods using rotating loops and resonance lines are included and a brief discussion of microwave impedance standards is given.
Date: August 12, 1965
Creator: Beatty, Robert W.
Partner: UNT Libraries Government Documents Department

Oxidation of Polycyclic, Aromatic, Hydrocarbons: A Review of the Literature

Description: Report discussing the literature on the oxidation of polycyclic, aromatic hydrocarbons. Information has been assembled on (1) the oxidants effective in the oxidation of such hydrocarbons, (2) the relative reactivity of the hydrocarbons, (3) the conditions under which oxidation proceeds, (4) the chemical mechanisms involved when such oxidations occur, and (5) the products formed.
Date: September 17, 1965
Creator: Tipson, R. Stuart
Partner: UNT Libraries Government Documents Department

Spot Diagrams for the Prediction of Lens Performance From Design Data

Description: From Abstract: "This Monograph presents an outline of the methods used at the National Bureau of Standards to predict the performance of lenses from an analysis of their designs. The technique is based on the use of spot diagrams, which are analogs of star image tests, and makes extensive use of high-speed digital computers."
Date: September 7, 1965
Creator: Stavroudis, Orestes N. & Sutton, Loyd E.
Partner: UNT Libraries Government Documents Department

A Table of Radiation Characteristics for Uniformly Spaced Optimum Endfire Arrays with Equal Sidelobes

Description: From Abstract: "Numerical results, in table form, on the required phases, the directive gain, the current excitations, the location of all the sidelobes and nulls, and the beamwidths for uniformly spaced optimum endfire arrays with equal sidelobes are given."
Date: December 10, 1965
Creator: Ma, M. T. & Hyovalti, D. C.
Partner: UNT Libraries Government Documents Department

Thermodynamic and Related Properties of Parahydrogen From the Triple Point to 100 K at Pressures to 340 Atmospheres

Description: 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.
Partner: UNT Libraries Government Documents Department