Preface: On its 80th anniversary, the National Bureau of Standards hosted a series of lectures by six distinguished speakers of national and international note who discussed the challenges facing science and technology and, thus, the Bureau in the coming years. This publication contains the texts of these presentations, along with transcripts of the question-and answer sessions following the presentations. The lecture series was organized by Dr. Donald R. Johnson of NBS with the very able assistance of Mrs. Carol Shipley in making arrangements for speakers and handling the manuscripts. The staff of the NML Text Editing Facility are acknowledged for their substantial contributions of typing and editing support.

Abstract: The Workshop on Measurement of Electrical Quantities in Pulse Power Systems addressed measurements in pulse systems having the characteristics of pulse duration less than a millisecond, system voltages greater than 10 kilovolts, and system currents greater than 10 kiloamperes. The presented papers were divided into four categories: voltage measurements; current measurements; power and energy measurements, and data acquisition. Included are discussions of applications of conventional measurement techniques and state-of-the-art systems.

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.

Abstract: The symposium on Oil and Gas Supply Modeling, held at the Department of Commerce, Washington, DC (June 18-20, 1980), was funded by the Energy Information Administration of the Department of Energy and co-sponsored by the National Bureau of Standards' Operations Research Division. The symposium was organized to be a forum in which the theoretical and applied state-of-the-art of oil and gas supply models could be presented and discussed. Speakers addressed the following areas: the realities of oil and gas supply, prediction of oil and gas production, problems in oil and gas modeling, resource appraisal procedures, forecasting field size and production, investment and production strategies, estimating cost and production schedules for undiscovered fields production regulations, resource data, sensitivity analysis of forecasts, econometric analysis of resource depletion, oil and gas finding rates, and various models of oil and gas supply. This volume documents the proceedings (papers and discussion) of the symposium.

Annual report describing the activities and goals of the National Voluntary Laboratory Accreditation Program (NVLAP) during 1981, and a directory list of laboratories including the test methods for which they are accredited.

Abstract: The input impedance of a probe antenna exciting a transverse electromagnetic (TEM) transmission line cell is formulated by a variational approach. The formulation also utilizes the results from a previous work on the field distribution inside a TEM cell excited by a vertical electrical Hertzian dipole. The final result of imoedance is shown to consist of two distinct terms, which are respectively contributed by the ordinary rectangular waveguide and the gap perturbation. Numerical results for both the real and imaginary parts of the impedance are given. The resistive part is found to be proportional to the square of the probe length, and the reactive part largely capacitive.

Abstract: Using a modified version of the nonanalytic equation of state, thermophysical properties of isobutane are derived from physical properties data and are tabulated at integral temperatures over the entire range of fluid states from 114 to 700 K along isobars at pressures to 70 MPa. Results include dielectric constants, densities, enthalpies, entropies, equation of state, internal energies, isobars, isochores, isotherms, Joule-Thomson inversion, heats of vaporization, melting line, orthobaric densities, specific heats, sound velocities, vapor pressures, and virial coefficients. In addition to the equation of state, equations are given for vapor pressures, orthobaric vapor and liquid densities, ideal gas properties, second virial coefficients, dielectric constants, heats of vaporization, melting pressures, and orthobaric liquid specific heats, enthalpies, and entropies. Several new sets of data have been used in this correlation; comparisons between experimental and calculated values are given.

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: Densimeters for liquefied natural gas (LNG) from four manufacturers were tested in liquid methane and an LNG-like mixture of methane, propane, and nitrogen in the density reference system (DRS). The calibration and performance of one type tested for the first time are reported. The stability of the calibrations and performances of three densimeters of a type previously tested have been examined and are also reported here.

Abstract: As a first step in the development of a beam-profile measuring instrument for laser sources that is capable of determining the distribution of low-order (less than 25) Hermitian modes in a series of laser pulses, I designed and evaluated the three key parts of such an instrument. First, there is the telescope system which allows the incident laser beam to be phase, beamwidth, and beam center matched to the optical spatial filter. Second, there is a brief error analysis of the structure of the mismatch function between the beam out of the telescope and that expected by the filter. Finally, there is the detailed analysis and design of the computer-generated spatial filter that will cause the incident-laser beam to be cross correlated with the low-order Hermite modes and will create an array of light spots in the detector (Fourier transform) plane each of which can be uniquely related to a particular Hermite mode of the original laser pulse. The principal conclusion is that the Hermite mode analysis can be done with better than 99 percent separation between modes, provided the phase between modes is uncorrelated from pulse to pulse when the filter has been fabricated with a two-level, gray-scale …

From introduction: For the first time, transfer standards have been developed for measuring 1.064 Pm laser pulses of duration about 10-100 ns, peak irradiance of about 10-8-10-4 W/cm2, and fluences of about 10-16-10-11 J/cm2 . These energy and power measurement devices use PIN and APD silicon detectors, respectively, and can be used as stable transfer standards with total uncertainties (random errors computed at the 95 percent confidence level) of 10 to 15 percent. The system for calibrating these transfer standards is also described and consists of a cw Nd:YAG laser beam acousto-optically modulated to provide low-level laser pulses of known peak power and energy. A detailed evaluation of systematic and random errors is also shown.

From introduction: A new method for determining the radiation characteristics of leakage from electronic equipment for interference studies is described in this report. Basically, an unintentional leakage source is considered to be electrically small, and may be characterized by three equivalent orthogonal electric dipole moments and three equivalent orthogonal magnetic dipole moments. When an unknown source object is placed at the center of a transverse electromagnetic (TEM) cell, its radiated energy couples into the fundamental transmission mode and propagates toward the two output ports of the TEM cell. With a hybrid junction inserted into a loop connecting the cell output ports, one is able to measure the sum and difference powers and the relative phase between the sum and difference outputs. Systematic measurements of these powers and phases at six different source object positions, based on a well-developed theory, are sufficient to determine the amplitudes and phases of the unknown component dipole moments, from which the detailed free-space radiation pattern of the unknown source and the total radiated power can be determined. Results of simulated theoretical examples and an experiment using a spherical dipole radiator are given to illustrate the theory and measurement procedure.

Report issued by the National Bureau of Standards over thermal tests conducted on soil samples. The results of the laboratory tests are discussed. This report includes tables, illustrations, photographs.

Report issued by the National Bureau of Standards over transporting discrete solids in partially-filled flow pipes. The methods and application of drainage flow are discussed. This report includes tables, illustrations, and photographs.

Report issued by the National Bureau of Standards over testing procedures used for solar domestic water heating systems. Testing methods are discussed. This report includes tables, illustrations, and photographs.

Report issued by the National Bureau of Standards over the history and development of sign systems in the United States. The research and development of more effective systems are discussed. This report includes tables, and illustrations.

Report issued by the National Bureau of Standards over studies conducted on load displacement of shallow soil anchors. Characteristics and testing methods are discussed. This report includes graphs, illustrations, and photographs.

Report issued by the National Bureau of Standards documenting investigations conducted on construction failures of two suspended walkways in a Kansas City hotel. It includes tables, illustrations, photographs, and other details of the investigation.

Report issued by the National Bureau of Standards over investigations of construction failure in Cocoa Beach, Florida. Factors for the construction failure are discussed. This report includes tables, illustrations, and photographs.

Report issued by the National Bureau of Standards over experiments conducted on a masonry building constructed inside an environmental chamber at the NBS. Different climactic conditions were simulated and the thermal response of the building was evaluated. This report includes tables, illustrations, and photographs.

Report issued by the National Bureau of Standards over solar heating and cooling systems in residential buildings. The performance criteria for solar systems are discussed. This report includes illustrations.

Report issued by the National Bureau of Standards over investigation of the collapse of a concrete cooling tower on Willow Island, West Virginia. Results of field, and laboratory tests are discussed. This report includes tables, illustrations, and photographs.