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Key words: Al2O3; As S, glass; BaFz; CaFz; CDFz; chalcogenide glass; elastic compliances; elastic constants; elastooptic constants; fused silica; Ge; hot forged; KBr; KCI; KCI:KI; LiF; MgF2; NaCl; NaF; piezo-optic constants; refractive index; SiO,; SrF2; thermal expansion coefficient;

thermo-optic constant; ZnS; ZnSe. Data obtained as part of the Optical Materials Characterization Program are summarized in this report. Room temperature values of refractive index as a function of wavelength are presented for the following materials: commercially grown KCI, reactive atmosphere processed (RAP) KCI, KCI nominally doped with 1.5% KI, hot forged CaFz, fusion cast CaFz, CaF, doped with Er (0.001% to 3% Er), SrF2, chemical vapor deposited (CVD) ZnSe (2 specimens), and ZnS (CVD, 2 specimens). Data for the thermo-optic constant (dn/dT) and the linear thermal expansion coefficient are given for the following materials over the temperature range – 180 °C to 200 °C: AlO3, BaFz, CaF2, CdF2, KBr, KCI, LiF, MgF2, NaCl, NaF, SrF2, ZnS (CVD), and ZnSe (CVD). The piezo-optic constants of the following materials are presented: AszSg glass, CaF2, BaFz, Ge, KCI, fused SiO2, SrF2, a chalcogenide gli (Ge 33%, As 12%, Se 55%) and ZnSe (CVD).

This report presents the results of a study of the impact of regulations on building rehabilitation and includes a discussion of the activities of the Building Rehabilitation Technology Program of the Center for Building Technology. Particular activities discussed relative to existing buildings include: (a) develop ment of the technical bases for regulations and an improved regulatory process, (b) development of new technology and evaluation tools, and (c) development of responsive and costeffective decision tools. A new code concept is outlined which could be a replacement for the “25-50 percent" rule presently in codes for new construction. This rule often controls the amount of work that may be required in the rehabilitation of existing buildings. The status of existing code documents for building rehabilitation is provided along with an overview of other publications which discuss the impact of building regulations on rehabilitation.

TN995. NBS Reactor: Summary of activities—July 1977 to June

1978, F. J. Shorten, Ed., Nar. Bur. Stand. (U.S.), Tech. Note 995, 147 pages (May 1979) SN003-003-02070-2.

Key words: activation analysis; crystal structure; diffraction; isotopes; molecular dynamics; neutron; neutron radiography; nondestructive evaluation; nuclear reactor; radiation.

TN999. A study of the dynamic flue-gas temperature and off

period mass flow rate of a residential gas-fired furnace, C. Park, W. J. Mulroy, and G. E. Kelly, Nat. Bur. Stand. (U.S.). Tech. Note 999, 41 pages (July 1979) SN003-003-02092-3.

Key words: automatic stack damper; flue-gas temperature profile; gas-fired furnace; off-period mass flow rate; part

load performance; seasonal efficiency. The flue-gas temperature and mass flow rate through a gasfired furnace were studied in the laboratory. Temperature profiles were measured under cycling conditions and compared with profiles predicted mathematically using data obtained while the furnace was cooling down from steady-state operation and warming up from equilibrium. The mass flow rates at various flue-gas temperatures were measured using both a vane anemometer and a tracer-gas technique, and these results are compared with the mass flow rate predicted by the theoretical equations. The effect on the off-period flow rate of automatic stack dampers having different sized damper openings was experimentally determined. Theoretical equations are presented for predicting the effectiveness of a stack damper as a function of the ratio of the area of the damper to the area of the stack and a system friction factor.

This report summarizes all those programs which depend on the NBS reactor. It covers the period from July 1977 through June 1978. The programs range from the use of neutron beams to study the structure and dynamics of materials through nuclear physics and neutron standards to sample irradiations for activation analysis, isotope production, radiation effects studies, neutron radiography and nondestructive evaluations.

TN996. Mechanical properties of adobe, J. R. Clifton and F. L.

Davis, Nar. Bur. Stand. (U.S.), Tech. Note 996, 45 pages (May 1979) SN003-003-02066-4.

Key words: adobe; adobe soil; compressive strength; creep; flexural strength; mechanical properties; moisture; non

destructive testing; preservation. Relationships between the compressive strength and creep, and the moisture contents of adobe were investigated. Moisture was found to have a deleterious effect on these mechanical properties of adobe, its severity increasing with increasingly higher relative humidities and higher moisture contents. It was concluded that rain and ground water would have a greater deleterious effect on the mechanical properties of adobe than high relative humidities.

The physicochemical properties of adobe, mix proportions, drying conditions, and shrinkage of specimens were also found to influence the compressive strength of adobe. Procedures for preparing, curing and testing of adobe specimens are given.

A nondestructive test method, based on measuring the penetration resistance of adobe, was found to give reliable predictions of the compressive strength and moisture content of adobe specimens.

TN1008. Antennas and the associated time domain range for the

measurement of impulsive fields, R. A. Lawton and A. R. Ondrejka, Nar. Bur. Stand. (U.S.), Tech. Note 1008, 68 pages (Nov. 1978) SNOO3-003-01998-4.

Key words: antenna; conical transmission line; impulse

response; impulsive fields; standards; TEM horn antenna. This report describes the construction and evaluation of a TEM horn antenna designed at NBS to be used as a transfer standard to generate and measure impulsive electromagnetic fields. Our purpose in the evaluation was to analyze the different electrical field generation and measurement techniques thoroughly enough to determine the major sources of error and establish a standard of impulsive field strength having a well established statement of accuracy.

The evaluation of this horn was done in two independent ways; by placing the horn in the field of a conical transmission line and by a three antenna intercomparison. The two methods were found to agree within + 3 dB over the range of 0.6 to 5 GHz. Part of this disagreement is due to the assumption of far field conditions, and an experimental technique is described which determines the frequency range over which this assumption is valid.

TN998. Impact of building regulations on rehabilitation-Status

and technical needs, J. G. Gross, J. H. Pielert, and P. W. Cooke, Nat. Bur. Stand. (U.S.), Tech. Note 998, 50 pages (May 1979) SN003-003-02062-1.

Key words: building code; building research; code administration; existing buildings; model codes; preservation; regulation; rehabilitation; renovation.

TN1009. Laser beam profile measurements using spatial sam

pling, Fourier optics, and holography, E. G. Johnson, Jr., Nai. Bur. Stand. (U.S.), Tech. Note 1009, 96 pages (Jan. 1979) SN003-003-02019-2.

ment Shops Division personnel. This paper provides the sequential procedure used to fabricate this cell, in conjunction with a complete set of detail and assembly drawings used to illustrate the complete fabrication process. The purpose of this publication is to provide documented information sufficient for any outside vendor, with the proper facilities, to construct a similar TEM cell.

TN1012. Calibrating a six-port reflectometer with four im

pedance standards, C. A. Hoer, Nat. Bur. Stand. (U.S.), Tech. Note 1012, 24 pages (Mar. 1979) SNOO3-003-02036-2.

Key words: amplitude; beam profile; cross correlation; digital sampling; Fourier optics; holography; laser; laser parameters; laser pulse; optical processing; phase; precision

measurements; wave front. Using appropriate holography, lenses, mirrors, and a twodimensional array of small holes to sample the electric field of a laser pulse, we demonstrate a technique for beam profile measurements at a preselected observation plane. This method can measure the amplitude and phase of a laser pulse at each preselected sampling point on a transverse observation plane. Subject to constraints, these measurements can provide separated visual images of the temporal pulse shapes for the amplitude and phase at each of the sampled electric fields. This paper describes the basic concepts for beam profile measurements via holography and uses pictures generated by a prototype system for illustration.

This unit may be calibrated by using a cw laser beam of the same wavelength as the carrier or a Q-switched laser pulse. Therefore, a user can make beam profile measurements of a laser pulse in real time. This technique requires appropriate scaling of the lenses and mirrors, and uses a different hologram to allow the unit to work optimally for each wavelength.

We define the potential limits and virtues of the holographic method. In addition, we define limits and virtues of other beam profile techniques such as the two-pinhole scanning method and the Hartmann plate method.

Finally, we indicate possible directions for eventual commercial and scientific exploitation of the holographic method. The technique can be used for near- and far-infrared wavelengths and, with appropriate changes in the optics, for visible wavelengths.

Key words: calibration; impedance; reflection coefficient;

reflectometer; six-port. This report is a theoretical study showing how four terminations of known impedance can be used to calibrate a six-port reflectometer for measuring other terminations of unknown inpedance. The equations for obtaining the calibration constants are exact but nonlinear, requiring an iterative solution. Several ways are described for using these constants to calculate the impedance of terminations being measured with the six-port reflectometer.

TN1013. Using a TEM cell for EMC measurements of electronic

equipment, M. L. Crawford and J. L. Workman, Nat. Bur. Stand. (U.S.), Tech. Note 1013, 72 pages (Apr. 1979) SN003-003-02053-2.

Key words: measurement procedures; susceptibility and

emission measurements; transverse electromagnetic cell. This publication describes the physical design and electrical evaluation of pertinent parameters which influence the use and operation of a transverse electromagnetic (TEM) cell. Detailed, step by step procedures are given for using a TEM cell for performing either radiated EM susceptibility testing or for measuring radiated EM emissions from electronic/electro-mechanical equipment. These measurement procedures provide guidelines to potential users and also indicate precautions to observe to minimize problems often encountered when performing EMC measurements and hence to enhance the cell's usefulness. Where available, a brief error analysis associated with the measurement technique is included.

TN1010. Measurement of pulsed-laser power, M. Young and R.

A. Lawton, Nat. Bur. Stand. (U.S.), Tech. Note 1010, 40 pages (Feb. 1979) SNOO3-003-02028-1.

Key words: attenuators; calibration; laser; neodymium laser; peak power; power meter; pulsed laser; Q-switched;

risetime; speckle; waveform. We describe calibrating several optical-pulse power meters to an accuracy of about 8% or better. The meters are designed for Q-switched neodymium lasers with peak powers in excess of a few megawatts and pulses longer than five or ten nanoseconds. Combined with a fast oscilloscope or a transient digitizer, the meters display the time-domain waveform of the laser emission and thereby allow determination of parameters such as transition duration (risetime, falltime), duration and peak power. We discuss calibrating the meters by both pulsed and cw methods, and show why each method is useful as a check on the other. We treat in some detail the effect of speckle on the use of diffusers as attenuators in power meters such as ours.

TN1014. Electromagnetic interference (EMI) radiative measure

ments for automotive applications, J. W. Adams, H. E. Taggart, M. Kanda, and J. Shafer, Nat. Bur. Stand. (U.S.), Tech. Note 1014, 48 pages (June 1979) SNOO3-003-02086-9.

Key words: mobile-radio; near-field strength levels; vehicular electromagnetic environment; vehicular near-zone electric fields; vehicular near-zone magnetic fields; worst-case EM fields.

TN1011. Construction of a large transverse electromagnetic cell,

W. F. Decker, W. A. Wilson, and M. L. Crawford, Nat. Bur. Stand. (U.S.), Tech. Note 1011, 92 pages (Feb. 1979) SN003-003-02034-6.

Key words: electromagnetic susceptibility testing; structural design and fabrication procedures; transverse electromag

netic (TEM) cell. In support of the electromagnetic interference studies underway in the Electromagnetic Fields Division of the National Bureau of Standards, a 2.8 meter transverse electromagnetic (TEM) cell was constructed by the Instrument Shops Division of the NBS Boulder Laboratories.

The cell requirements, design concepts, and fabrication procedures were developed through the coordination of both the Electromagnetic Fields Division personnel and the Instru

This report describes the measured results of the electromagnetic (EM) environment encountered by three different-sized vehicles exposed to a selection of CB and mobile radio transmitters and broadcast stations. The vehicle in these situations is immersed in the near field of the radiating signals and the measured data is near-field data. This report gives measured data of electric and magnetic fields measured independently. The purpose of the report is to identify the EM environmental conditions under different circumstances in order to estimate EMC testing criteria for vehicles and their electronic systems.

TN1015. Design of a reflection apparatus for laser beam profile

measurements, E. G. Johnson, Jr., Nat. Bur. Stand. (U.S.), Tech. Note 1015, 124 pages (July 1979) SN003-003-02103. 2.

Key words: beam profile; calibrated system; holography; irradiance; laser diagnostics; phase front.

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Measurement of both the irradiance and phase front (the beam profile) in real time from the output of a laser has interest for control of that beam and for efficient energy and economic design of the source and the resulting optical systems. The National Bureau of Standards (NBS) has begun a program to build a unit that can measure, at numerous wavelengths from 1.06 um to 10.6 mm, a selected spatial sample of the beam profile. This device would have the following features: (1) The different carrier wavelengths use the same apparatus by changing two mirrors. (2) The beam profile is sampled simultaneously with no time-shift distortions. (3) The output data streams documenting the sampled beam profile are continuous and are distorted only by the finite number and the time constants of the detectors. (4) The phase-front information is generated before the detectors create the data streams. (5) The apparatus uses mirrors and a reflection hologram that is computer generated. (6) The unit is calibrated piecewise over the range of relative phase and irradiances for each pair of neighboring sampling holes which are 5 mm apart. (7) The resulting calibrated unit can measure profiles near 10 cm in diameter with phase-front variations of less than 5 wavelengths. (8) The expected response time for measurements as controlled by the electronics is of the order of several tens of nanoseconds.

The design analysis reported here includes: (1) the theory which uses Fourier optics concepts with off-axis reflections and rough surfaces to provide the basis for accurate computer simulation of laser beams; (2) the program, BEAM, which generates the expected behavior of the apparatus under variation of laser wavelength, physical dimensions for curvatures, hologram structure, and changes in positions of the various components; (3) the simulation results which demonstrate the expected characteristics for the apparatus; and (4) the key element in the apparatus, namely the reflection hologram, which requires discussion of the design, construction, and testing of this element.

The Hartmann plate method is described briefly so that a comparison between it and the holographic method can be made. The comparison shows why the holographic method is best for a standard for irradiance and phase-front measure

information networks; network; seismic design; systems

analysis. This report presents the results of a thorough study of the internal logic of the Tentative Provisions for the Development of Seismic Regulations for Buildings developed by the Applied Technology Council. The methods of analysis employed in the study provide objective measures of clarity, completeness, and consistency and an alternative form in which to examine the technical validity of the provisions. These methods include decision logic tables for examining individual provisions, information networks for representing the precedence among provisions, and classification of the provisions to study their scope and arrangement. A formal representation of the provisions is presented by the data items, decision tables, networks, and classification systems developed in the study. An index and several alternate arrangements of the provisions are also included. Opportunities for improvement of the tentative provisions are identified and discussed, and considerations for their future development and implementation within various national standards are highlighted. TN1101. Decision analysis of strategies for reducing upholstered

furniture fire losses, S. G. Helzer, B. Buchbinder, and F. L. Offensend, Nat. Bur. Stand. (U.S.), Tech. Note 1101, 155 pages (June 1979) SNOO3-003-02078-8.

Key words: building fires; cost-benefit analysis; costs; decision analysis; fire losses; furniture; hazard analysis; probability; residential buildings; sensitivity analysis; smoke de

tectors; standards; upholstered furniture. Decision analysis is used to evaluate alternative strategies for reducing residential upholstered furniture fire losses. Three alternatives are evaluated: no-action, mandatory smoke detector installation, and the proposed upholstered furniture standard under consideration by the Consumer Product Safety Commission. Quantitative models are developed to assess fire losses and cost under each alternative. The alternatives are evaluated on the basis of minimizing the total cost plus loss to society over time. Subject to the assumptions set forth in the report, the analysis shows that the detector alternative and the proposed standard are essentially equivalent and preferred to the no-action alternative. The proposed standard is more effective in saving lives, whereas the detector alternative is less costly to implement. The sensitivity of the results to key assumptions and input parameters is tested. The results are shown to be particularly sensitive to the cost of the proposed standard, the loss of life value assignment, and the upholstered furniture replacement pattern.

ments.

TN1016. A standard for r modulation factor, M. G. Arthur and

G. R. Reeve, Nat. Bur. Stand. (U.S.), Tech. Note 1016, 92 pages (Sept. 1979) SN003-003-02125-3.

Key words: amplitude modulation; instrument landing system (ILS); measurement instrumentation; measurement standard; modulation; modulation factor; modulation meter; Newton-Raphson method; percent modulation;

signal generator; vhf omnidirectional radio range (VOR). A modulation factor standard has been developed to support the Federal Aviation Administration's requirements for a measurement capability for the ILS and VOR navigation systems. The standard consists of both a precision modulation meter and a stable amplitude-modulated signal source. Although designed primarily for ILS and VOR signals, it has general purpose capabilities within an of range of 10 MHz to 500 MHz and an af range of 20 Hz to 20 kHz. Measurement uncertainty is less than 0.11 percent modulation below 90 percent modulation for ILS/VOR tones of 90 Hz and above, and is somewhat greater than 30 Hz. Included are a circuit description and an error analysis.

TNI 102. Large scale integration digital testing-Annotated

bibliography, 1969-1978, T. F. Leedy, Nar. Bur. Stand. (U.S.), Tech. Note 1102, 44 pages (Aug. 1979) SNOO3-00302097-4.

Key words: electronics; integrated circuit; large scale in

tegration; memory; microprocessor, testing. This annotated bibliography covers articles published in the field of semiconductor device testing. The bibliography contains (1) entries divided into six economics of testing, (2) monolithic circuit testing, (3) the testing of subsystems of large scale integrated circuits such as microcomputer boards and memory arrays, (4) various test strategies used to locate a defective LSI circuit, (5) test equipment available for LSI testing, and (6) various measurement methods that may be of interest to the test engineer.

TNI 100. Analysis of tentative seismic design provisions for

buildings, J. R. Harris, S. J. Fenves, and R. N. Wright, Nat. Bur. Stand. (U.S.), Tech. Note 1100, 599 pages (July 1979) SN003-003-02084-2.

Key words: building codes; buildings; building standards; classification; decision tables; earthquake-resistant design;

TNI 103. Full-scale burning behavior of upholstered chairs, V.

Babrauskas, Nat. Bur. Stand. (U.S.), Tech. Note 1103, 86 pages (Aug. 1979) SNOO3-003-02110-5.

formats. Calibration techniques are discussed and representative calibration data are presented.

Key words: chairs, compartment fires; fire tests; flamma

bility; furnishings; upholstered furniture. A test program was conducted to determine the fire behavior of a variety of upholstered chairs subjected to a flaming ignition. Major variables were materials and construction of chairs, room ventilation, and type of ignition sources. A total of 16 types of traditional and modern design chairs were tested in a full-scale, otherwise unfurnished room. A folded up newspaper at the seat area was used as the standard ignition source. Room tenability criteria were based on smoke, concentrations of gaseous combustion products, and heat flux. One or more tenability criteria were exceeded for 14 chairs, in times ranging from 100 sec to 650 sec; two chairs burned without exceeding any of the tenability criteria. A review is included of previous upholstered furniture experiments using flaming ignition sources and of existing or proposed small-scale standard tests. TNI 104, Vols. 1 and 2. The FCC public message services policy

change: An ETIP evaluability assessment report, J. Bell, S. Kirby, R. G. Weiss, and S. Watson, Nat. Bur. Stand. (U.S.), Tech. Note 110411, 232 pages, 1104/2, 110 pages (Sept. 1979) SN003-003-02117-2,

TNT 106. Frame C: A compact procedure for quantitative ener•

gy-dispersive electron probe x-ray analysis, R. L. Myklebust, C. E. Fiori, and K. F. J. Heinrich, Nat. Bur. Stand. (U.S.), Tech. Note 1106, 111 pages (Sept. 1979) SN003-003-021130.

Key words: computer program; energy dispersive detector; multichannel analyzer; peak overlap; quantitative electron

probe microanalysis; x-ray continuum; x-ray spectrum. A data evaluation procedure (FRAME C) for carrying out quantitative electron probe microanalysis with a lithium-drifted silicon detector was developed for use with a small computer. The procedure consists of a background correction calculated from two selected background regions of interest, a simple method of resolving overlapping peaks, and the matrix corrections for characteristic radiation (ZAF). To save computation time, small groups of adjacent channels (regions of interest) in the multi-channel analyzer rather than individual channels are used for the calculations. The method for computing the overlap factors is described. Examples of several types of analyses are presented. TNI 107. The use of aerial infrared thermography to compare

the thermal resistances of roots, D. M. Burch, Nat. Bur. Stand. (U.S.), Tech. Note 1107, 38 pages (Aug. 1979) SN003-003-02102-4.

Key words: aerial flyovers; aerial infrared thermography;

energy conservation; roof heat-loss survey. The paper investigates whether a comparative roof survey using aerial infrared thermography can be used to rank the roofs of residential and commercial buildings according to their thermal resistance. Mathematical models are presented for predicting the apparent radiance temperatures of these roof systems. These models are used to investigate the differences in apparent radiance temperature between roofs having various thermal resistances. These predicted differences are then compared with predicted differences in apparent radiance temperature caused by typical variations in roof emittance, local outdoor temperature, and local wind speed throughout the macroclimate. The transmission characteristics of the atmosphere are reviewed, and the required dew-point spread for preventing dew or frost formation on a roof is examined.

Key words: administrative experimentation; economic deregulation; evaluability assessment; evaluation; Experimental Technology Incentives Program; Federal Communications Commission; regulatory experimentation; regulato

ry policy; technology innovation; telecommunications. This document is a report of work in progress toward evaluating effects of the recent decision of the Federal Communications Commission to open public message services to competition. It is one product of the Regulatory Processes and Effects Project of the Center for Field Methods (ETIP). The broader project, described elsewhere, is attempting to analyze the effects of changes in regulatory processes on industrial innovation. The joint ETIP/FCC project will involve measuring whether the FCC policy change leads to increases in competition, technological innovation, and public benefit.

The first two chapters provide an introduction and synopsis. Chapter II examines the setting in which the decision occurs in terms of historical developments, industry trends, and views held by various observers. Chapter IV describes the: Commission's mandate for regulation, process for implementing this mandate in terms of regulations and operations, and current industry status. The fifth chapter describes the evaluation logic. The last chapter is an assessment which shows that there are many choices to be made to target the evaluation. A glossary of terms and bibliography are included. Seven appendices are bound separately. TNI 105. A 20 bit + sign, relay switched D/A converter, T. M.

Souders and D. R. Flach, Nat. Bur. Stand. (U.S.), Tech. Note 1105, 21 pages (Oct. 1979) SNOO3-003-02129-6.

Key words: digital-to-analog converter; high resolution; multirange; R-2R ladder; relay switching; self-calibration;

twenty bits + sign; voltage output. A multirange, 20-bit + sign, voltage output d/a converter is described. The converter exhibits less than 1 ppm (of full scale range) linearity error, and temperature coefficients of gain, offset and linearity of less than 0.5 ppm/°C. The design is based on the R-2R ladder network in the current steering mode, using miniature latching relays with mercury wetted contacts for switching. Ten buffered, temperature-controlled unsaturated standard cells comprise the voltage reference.

Techniques with design details are presented for minimizing errors due to relay thermal emf's, for implementing a selfcalibration of linearity errors, and for obtaining optional coding

TNI 108. SPEED2, a computer program for the reduction of

data from automatic data acquisition systems, R. D. Peacock and J. M. Smith, Nat. Bur. Stand. (U.S.), Tech. Note 1108, 153 pages (Sept. 1979) SN003-003-02112-1.

Key words: computer program; data acquisition systems;

data reduction; plotting. The voluminous amount of data that can be collected by automatic data acquisition systems requires the use of a digital computer for the reduction of data. A general purpose computer program for the reduction of data collected by automatic data acquisition systems is presented. The program is written with the ability to accept data from a number of different data acquisition systems, with the ability to check the correctness of data included. Through the use of FORTRAN computer programming, the data can be converted to meaningful scientific and engineering units. The data can then be presented in tabular, printer plot or ink pen plot form.

The program is documented, and detailed instructions for its use, with examples, are presented. The use of SPEED2 requires some knowledge of FORTRAN programming language and the executive control language for the computer system in use.

TNI 109. Characterization of electrical ignition sources within

television receivers, G. J. Rogers and D. D. Evans, Nar. Bur. Stand. (U.S.), Tech. Note 1109, 60 pages (Oct. 1979) SN003-003-02119.9.

Key words: electrical failure; fire containment; ignition;

television fire. The ignition of television receivers initiated by electrical failures in the circuitry was examined by studying four receivers. They were: two black and white portables, a color portable, and a color console receiver. Selected locations within the circuitry were stressed by introducing full or partial short circuits to simulate the failure of electronic components. The temperatures and increased power dissipation generated by short-circuited components were recorded. Although component temperatures greater than 500 °C were achieved, no flaming ignition sources were generated.

For comparative purposes the energy release rate of the ignition source specified in the UL 1410 test procedure was measured. Supplemental measurements on the operating temperatures of chassis components under varying ventilation conditions were also made.

TN1110. NBS interagency transducer project 1951-1979—An

overview, P. S. Lederer, Nar. Bur. Stand. (U.S.), Tech. Note 1110, 45 pages (Aug. 1979) SN003-003-02109-1.

Key words: dynamic calibration; evaluation; interagency transducer project; performance characteristics; telemetry; transducer.

Between 1951 and 1979, the National Bureau of Standards was engaged in a continuing project to study the performance of sensory transducers, primarily those used in telemetry. This project has been supported by agencies of the Defense Department and NASA. This report provides a brief description of the background and history of the project, of its objectives, of some of the techniques and specialized facilities developed and used, and of some of the publications that have been issued from the project.

5.13. CONSUMER INFORMATION SERIES

Practical information, based on NBS research and experience, covering areas of interest to the consumer. Easily understandable language and illustrations provide useful background knowledge for shopping in today's technological marketplace. CIS4, Revised 1978. Corrosion, E. L. R. Corliss, Nat. Bur.

Stand. (U.S.), Consum. Inf. Ser. 4, 31 pages (Revised 1978) SN003-003-02024-9.

Key words: audition; communications; hearing; hearing

aids; selection of hearing aids; speech communication. A consumers information publication containing information on hearing aids including selection, use, and maintenance.

.

CIS9, Revised 1979. Facts about hearing and hearing aids, J.

Kruger and S. Halpin, Eds, Nat. Bur. Stand. (U.S.), Consum. Inf. Ser. 9, 12 pages (Revised June 1979) SN003-003-019470.

Key words: corrosion; crevice corrosion; galvanic corro

sion; inhibitors; pitting corrosion; rust; stress corrosion. This document explains what corrosion is, how it affects certain metals and, how to prevent it.

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