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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 271 records · Page 15

Checking flat conductor cable spacing by means of a moire pattern

Moire tester detects small variations in flat conductor cable spacing by a quick, visual inspection. This device compares the cable to be tested with the negative of a very precise standard cable. The moire, consisting of bands of light and dark zones and its irregularities, can be interpreted as errors in spacing.

Angele, W.↗

Volume-checking tool

Tool, consisting of a graduated storage vessel and a control panel, can determine the amount of gas entrained by fluid in a closed system, the amount of fluid remaining in a dried system of known volume, or the volume of a container of unknown size.

Erbe, C. J.↗

Chatter-free check valve - A concept

Valve head moves in spiral motion away from seat. Motion is controlled by travel of pin along spiral groove in valve guide. Clearances between pin and groove permit free motion of valve, but effectively dampen vibration and chattering.

Dunbar, J. E.↗

Numerical check on the accuracy of spherical-wave expansions.

A simple and sensitive test for evaluating the numerical accuracy of a spherical-wave expansion is presented. The basic idea is to compare two different expansions of the same electromagnetic field, computed with respect to different coordinate origins. The use of the technique is illustrated by an example based on the experimental pattern of a horn antenna.

Ludwig, A. C.↗

Dual stage check valve

A dual stage seat valve head arrangement is described which consists of a primary sealing point located between a fixed orifice seat and a valve poppet, and a secondary sealing point between an orifice poppet and a valve poppet. Upstream of the valve orifice is a flexible, convoluted metal diaphragm attached to the orifice poppet. Downstream of the valve orifice, a finger spring exerts a force against the valve poppet, tending to keep the valve in a closed position. The series arrangement of a double seat and poppet is able to tolerate small particle contamination while minimizing chatter by controlling throttling or metering across the secondary seat, thus preserving the primary sealing surface.

Whitten, D. E.↗

Modeling of a bubble-memory organization with self-checking translators to achieve high reliability.

Study of the design and modeling of a highly reliable bubble-memory system that has the capabilities of: (1) correcting a single 16-adjacent bit-group error resulting from failures in a single basic storage module (BSM), and (2) detecting with a probability greater than 0.99 any double errors resulting from failures in BSM's. The results of the study justify the design philosophy adopted of employing memory data encoding and a translator to correct single group errors and detect double group errors to enhance the overall system reliability.

Bouricius, W. G.↗

Computer checking of rotational line intensity factors for diatomic transitions.

Previously published analytical formulae for the rotational line intensity factors of diatomic molecules have been compared with results from a comprehensive computer program, which determines numerical intensity factors for both spin-allowed and spin-forbidden electric and magnetic dipole transitions in diatomic molecules. The comparison uncovered several typographical errors and a few algebraic errors in the published formulae. The changes required in the formulae to give agreement with the results from the computer program are tabulated.

Whiting, E. E.↗