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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

Oscillator Strengths and Transition Probabilities fro 3288 Lines of Fe I

Description: Report of a homogeneous set of intensity-related data calculated for 3288 spectral lines of Fe I in the region from 2100 to 9900 angstroms. The quantities tabulated in the present monograph include log (g__), log (gf), gf,f,gA, and A. Since recent investigations do not support excitations corrections in the case of Fe I and certain other spectra, the present tabulation incorporates a removal of that normalization function. This recalculation affects the values for all lines whose upper energy levels lie above 46000 cm -1 and should significantly improve the internal consistency of the present data.
Date: March 1968
Creator: Corliss, C. H. & Tech, J. L
Partner: UNT Libraries Government Documents Department

Theory and Methods of Optical Pyrometry

Description: 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.
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

Radio Meteorology

Description: Report compiling the work done in radio meteorology over the past ten years at the National Bureau of Standards' Central Radio Propagation Laboratory (CRPL). There is an emphasis upon the effects of the lower atmosphere on the propagation of radio waves. The CRPL group has concentrated upon the refraction of radio waves as well as the refractive index structure of the lower atmosphere on both synoptic and climatic scales. Additional chapters on radio-meteorological parameters and the absorption of radio waves by the various constituents of the lower atmosphere.
Date: March 1, 1966
Creator: Bean, B. R. & Dutton, E. J.
Partner: UNT Libraries Government Documents Department

Standard X-ray Diffraction Powder Patterns: Section 1. Data for 46 Substances

Description: Report discussing forty-six standard X-ray diffraction powder patterns. Fourteen are to replace twelve patterns already given in the X-ray Powder Data File, and thirty-four are for substances not previously included. The X-ray Powder Data File is a compilation of diffraction patterns from many sources and is used for the identification of unknown crystalline materials by matching spacing and intensity measurements. The patterns were made with a Geiger counter X-ray diffractometer, using samples of high purity.
Date: March 9, 1962
Creator: Swanson, Howard E.; Morris, M. C.; Stinchfield, Roger P. & Evans, Eloise H.
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

Creep and Drying Shrinkage of Lightweight and Normal-Weight Concretes

Description: From Scope of Investigation: "The work reported here is part of a continuing program concerning the long-term volume changes in concretes made from lightweight and normal-weight aggregates. The creep, drying-shrinkage, and strength data presented are for concretes made with 24 expanded shale lightweight aggregates and 5 natural, normal-weight aggregates. These aggregates were from widely separated geographical locations and were to be representative samples of aggregates being used in the production of structural concretes."
Date: March 4, 1964
Creator: Reichard, T. W.
Partner: UNT Libraries Government Documents Department

Development of High-Temperature Strain Gages

Description: From Introduction: "An improved high-temperature gage was needed, and in an attempt to fill this need an investigation was initiated in February 1954 in the Enameled Metals Laboratory at the National Bureau of Standards. The present Monograph constitutes a final summary on this program."
Date: March 17, 1961
Creator: Pitts, J. W. & Moore, D. G.
Partner: UNT Libraries Government Documents Department

Calibration Procedures for Direct-Current Resistance Apparatus

Description: From Object and Scope of This Paper: "This paper describes the apparatus and procedures used at the National Bureau of Standards for the measurement of d-c resistance when an accuracy of a few parts in a million is required. The object will be to explain procedures in detail and as simply as possible, with a minimum reference to theory."
Date: March 1, 1962
Creator: Brooks, Paul P. B.
Partner: UNT Libraries Government Documents Department

Mechanical Behavior of Crystalline Solids: Proceedings of a Symposium, April 28-29, 1962

Description: From Introduction: "These first three chapters from a background of introduction and general ideas about dislocations. The next two chapters are concerned specifically with properties of ceramic materials, with emphasis on single crystals."
Date: March 25, 1963
Creator: United States. Bureau of Standards.
Partner: UNT Libraries Government Documents Department

Research and Development in the Computer and Information Sciences: [Part] 1. Information Acquistion, Sensing, and Input: A Selective Literature Review

Description: From Introduction: "This report is the first of a series intended to provide a selective overview of research and development efforts and requirements in the somewhat overlapping fields of the computer and information sciences and technologies. The projected series of reports will attempt to outline the probable range of R & D activities in the computer and information sciences and technologies through selective reviews of the literature and to develop a reasonable consensus with respect to the opinions of workers in these and potentially related fields as to areas of continuing R & D concern for research program planning or review in these areas."
Date: March 1970
Creator: Stevens, Mary Elizabeth
Partner: UNT Libraries Government Documents Department

NBS Papers on Underground Corrosion of Steel Piling, 1962-1971

Description: From Introduction: "In this paper are presented the results obtained to date from the inspections of steel pilings. The investigation will be continued by additional inspections of pilings in other parts of the country in order to cover a winder range of soil environments."
Date: March 1972
Creator: Schwerdtfeger, W. J & Romanoff, Melvin
Partner: UNT Libraries Government Documents Department

Conductive Flooring for Hospital Operating Rooms

Description: Report issued by the Bureau of Standards over studies on the importance of conductive flooring in hospitals. Types of conductive flooring are compared, and tested. The methods and results are presented, and discussed. This report includes tables, illustrations, and photographs.
Date: March 21, 1960
Creator: Boone, Thomas H.; Hermach, Francis L.; MacArthur, Edgar H. & McAuliff, Rita C.
Partner: UNT Libraries Government Documents Department

Thermocouple Reference Tables Based on the IPTS-68

Description: 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.
Partner: UNT Libraries Government Documents Department

Thermocouple Materials

Description: 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.
Partner: UNT Libraries Government Documents Department

Properties of High-Temperature Ceramics and Cermets: Elasticity and Density at Room Temperature

Description: From Introduction: "The present paper contains detailed descriptions of the methods used in calculating both the elastic constants and the statistical parameters. These detailed descriptions have been included for two reasons: (1) To leave no doubt as to the exact procedure, and (2) to act as a guide to other workers who might wish to make similar determinations."
Date: March 1, 1960
Creator: Lang, S. M.
Partner: UNT Libraries Government Documents Department