From abstract: This paper describes a Bessel null technique to measure the frequency response of a frequency-modulated rf carrier and a program to automate frequency response measurements of signal generators with output frequencies from 0.450 to 2000 MHz. The measurements obtained using this technique are more precise than those obtained by a highly trained technician using a manual system.

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.

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."

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.

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."

Report issued by the National Bureau of Standards over the energy performance of a day-lighted building. The different models and functions are discussed. This report includes tables, graphs, illustrations, and photographs.

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."

Report issued by the National Bureau of Standards over wind speed data collected for the design of buildings. The wind speed data is discussed. This report includes tables.

From Introduction: "The object of this research was to identify and study some of the factors involved in premature failures and to relate the pertinent factors to roof performance."

Abstract: A review is given of the electrical resistance of materials at cryogenic temperatures. Measurement techniques, the data base, and uses of the data are presented. The emphasis is on metals and alloys of technological importance; a toxic which covers a large range of materials. Similarly, the treatment of theory and of measurement techniques is primarily for the user interested in the more practical aspects of the subject. In every instance, however, references are given which allow the reader to pursue the subject at any level.

Abstract: Energy-dispersive x-ray analysis with gas proportional detectors has been used widely in x-ray spectrochemical analysis. It was particularly useful in the detection of low-energy x-ray emission, before the commercial availability of the Blodgett-Langmuir pseudocrystals. With the development of solid-state x-ray detectors of high resolution, and improvement in associated electronics and computers, the interest in energy-dispersive x-ray analysis has increased enormously, to the point where it has replaced Bragg crystal diffraction spectrometry in many instances.

From abstract: The excitation of a transverse electromagnetic (TEM) cell by a vertical electric Hertzian dipole is analyzed where the gap between the septum and side wall is assumed to be small. Approximate expressions for the field distribution and characteristic impedance are derived. These expressions are numerically evaluated for some typical geometries, and good agreement with previously published results is shown. The formation also allows a vertical offset for the septum position, thus offering more flexibility of increasing the size of the test area to accommodate larger pieces of test equipment.

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.

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."

Report of the annual conference on weights and measures, hosted by the U.S. National Bureau of Standards in Washington D.C. It includes conference proceedings, a list of attendees, information about committees and officers, and other reports or commentaries discussed at the meetings.

A report on the national electrical safety code.

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."

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.

Abstract: The problem of measuring and characterizing complicated multiple-source, multiple-frequency electromagnetic environments is becoming more important and more difficult as electrical devices proliferate. This paper outlines three general approaches to the problem which are currently under investigation at the National Bureau of Standards. The three approaches are: 1) a statistical treatment of the spatial distribution of electromagnetic field intensities, 2) a numerical computation using a finite-difference (or lattice) form of the electromagnetic action functional, and 3) use of a directional probe to scan a volume. All three methods are still in the development stage, but each appears promising.

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."

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.

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."

Technical paper issued by the Bureau of Standards over tests conducted on the preparation of an alloy. The tests conducted, and their results are presented and discussed. This paper includes tables, illustrations, and photographs.

Report documenting standard x-ray diffraction powder patterns for various compounds, intended to replace previous data or provide information for new substances. It describes the methods and, for each substance, outlines any previous data as well as information about the sample used and structural data, with a table of diffraction patterns.