of propagation of error in a chain of laboratories, and the role of computers in the work of calibration laboratories. Length. Two five-day seminars discussed the philosophy of measurement, fundamental interferometry, electromechanical transducer evaluation and calibration, deformation theory, spectral light sources, and lasers. Laboratory work dealt with methodology in the measurement of gage blocks, polygons, surface plates, angle blocks, optical flats, surface finish, spherical and cylindrical diameters, and deformation. High Frequency and Microwave Noise. This 4-day seminar dealt with generation and measurement of noise, using both state-of-the-art and classical methods, ranging from high temperatures to cryogenic levels. It included laboratory demonstrations of plasmas as noise sources. THE NATIONAL STANDARD The National Standard Reference Data System began in 1963 when the Federal Council for Science and Technology requested NBS to assume responsibility for all Government-wide standard reference data compilation activities. This request took the form of a directive establishing NSRDS as a Federal policy. Under this directive NBS was requested to (1) coordinate existing data compilation and evaluation activities throughout all Government agencies; (2) establish standards of quality for the products to be designated as Standard Reference Data; (3) establish standards of methodology including machine processing; (4) establish other functions as required to ensure compatibility; and (5) operate a National Standard Reference Data Center. NSRDS is concerned, under these instructions, with the production and dissemination of compilations of critically evaluated data. A primary emphasis of the system is to maximize the utilization of numerical information already reported in the scientific literature, as opposed to new measurements. The program includes collection and evaluation of data from the literature, preparation of critical reviews dealing with the state of quantitative knowledge in a particular technical field, and computation of useful functions derived from Standard Reference Data or used in the interpretation of quantitative experiments. In order to implement its responsibilities for the National Standard Reference Data program, NBS has established an Office of Standard Reference Data. The Institutes for Basic Standards and Materials Research both make substantial contributions to this program. While data are developed along lines of scientific competency rather than management category. IBS generally develops data dealing with particles of atomic and molecular size while IMR developes data on the bulk properties of materials. For management purposes the technical area of concern has been divided into seven broad categories: (1) nuclear, (2) atomic and molecular, (3) solid state, (4) thermodynamic and transport, (5) chemical kinetics, (6) colloid and surface, and (7) mechanical. In each of these areas, efforts are being made to develop a comprehensive, coordinated program of data compilation projects. Existing programs under non-NBS sponsorship are taken into account and priorities are determined by consulation with groups of specialists from the academic world, from Government, and from industry. During 1966 general activities continued to follow the plan described in NBS publication NSRDS-NBS #1, "National Standard Reference Data System Plan of Operation" (obtainable from the Superintendent of Documents, U. S. Government Printing Office, Washington, D. C. 20402. Price 15 cents). Effective working relationships with program offices in other Government agencies were continued and expanded. These relationships cover a wide range of formal and informal functions, including participation in advisory conferences, establishment and monitoring of specialized compilation projects to fill a mission-oriented need, creation of jointly sponsored compilation projects and data centers on topics of mutual interest, and development of communication networks among related data centers and data projects. Communication and collaboration with privately sponsored and individual data compilation projects advanced during the year. Sources of information on such projects include the response to a questionnaire sent to the entire membership (100,000) of the American Chemical Society, and informal discussions with academic and industry scientists. Significant progress in NSRDS has been made with the appearance of a substantial volume of compilations of numerical data and related material. These reports, technical notes and other publications have established the usefulness of the program among those in the scientific community who have seen and used its output. The status of developments in primary areas of activity is described below. Nuclear Data Two meetings of the Advisory Panel on Nuclear Data were held, one in October 1965 at the National Bureau of Standards in Washington and a second in January 1966, in New York. The following recommendations were made: 1. Existing gaps in the scope of coverage of nuclear data should be filled by soliciting the aid of interesting individuals. Additional compilations of data are needed for the following: (a) Primary cosmic data. (b) Nuclear data in the medium energy region (20 MeV to 1 BeV). (c) Nuclear data in the resonance region and nuclear level densities. (d) The few-nucleon area. (e) Polarization phenomena. (f) Elementary particle data at energies above 1 BeV. (g) Certain types of reactor measurements (e.g., resonance integrals, neutron ages, etc.). (h) Positive bombardment results. 2. Emphasis on the use of automatic computers in the compilation field should continue. Not all compilers make adequate use of computers and those that do use different formats, both input and output. In some instances work is duplicated rather than shared. 3. Expansion of existing compilation groups and establishment of new ones should continue to receive priority. 4. The period of time between the scanning of scientific literature and the publication of an evaluated compilation is too long. Therefore an intermediate step, such as the publication of an annotated bibliography should be considered by all data centers. Appropriate user feedback to the compilation center with regard to the usefulness of such an index is necessary. 5. The use of an author-oriented index system such as one based on key words should be seriously considered. 6. A practical, economic mechanism for obtaining some kind of physical information (individual data points, calibration data, etc.) without the need for resorting to historical publishing processes (handbooks, data sheets, etc.) must be made available in the future. Atomic and Molecular Data Under this category, the Office of Standard Reference Data participated in the initiation or expansion of projects in the following areas: 1. Atomic energy levels. 2. Atomic transition probabilities. 3. Microwave spectral tables. 4. Cross sections for electron ionization processes. 5. Atomic and molecular collision process data. 6. Mass spectrometric bibliographic information and data. 7. Infrared spectra. 8. Molecular fundamental vibration frequencies. 9. Ionization and appearance potentials. Cooperative arrangements for joint support of projects of common interest have been made with the U. S. Atomic Energy Commission, Department of Defense, Advanced Research Projects Agency, and the American Society for Testing and Materials. In view of the existing complex network of suppliers and users of molecular spectroscopic data, it has been recognized that NSRDS programs should provide for explicit, well-defined statements of criteria to be applied in compiling and evaluating such data. One set of criteria, covering infrared spectra, has been prepared for the Office of Standard Reference Data by the Coblentz Society Board of Managers, and has been well received by spectroscopists. This approach will be extended in other areas. Solid State Data Although no major progress has been possible in expanding compilation activities in the area of solid state data, two programs have been initiated which combine thermodynamics and solid state properties. One is on the compilation of high pressure data and the other is the establishment of a Metals Data Center at NBS. The latter project will compile soft x-ray and nuclear magnetic resonance data, coordinate all metals data compilations currently in effect and, where possible, check it for interval consistency to produce Standard Reference Data on metals and metal systems. It is not the intention of the NBS group to reevaluate the data from existing data centers, but to collate and indicate voids and incompatibility in the data. Reference Work Prepared by Computer.-NBS is preparing a major scientific reference work using significant new computer techniques. This work, a third edition of Donnays Crystal Data, will be produced by tape-controlled photocomposition, and the editing of the tape will be done by computer. The text and data are being keyboarded into punched paper tape, partly from the previous edition, partly from new information. The keyboard also produces a typewritten copy, far less elaborate than the final printed copy; it is proofread and corrections are keyboarded into separate pieces of paper tape. All data from paper tapes are automatically transcribed on magnetic tape. The magnetic tapes are fed into a general-purpose computer, which first inserts the corrections and then performs a variety of editing tasks. The computer then prepares two alphabetical indexes, one by chemical formula, one by chemical compound name. Finally, the computer deletes certain keypunched signals which are not wanted in print, and breaks the copy into lines of proper length, inserting spaces between paragraphs, breaking into pages, inserting page headings and page numbers. The output of the computer appears on magnetic tape, which is automatically tran 62 |