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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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Mental patient performance in detecting and identifying visual signals under fixed interval schedule, noting nonuniform performance and comparing to normal subjects
Computer program for calculating visibility intervals between earth tracking station and planetary satellite
Time interval measurement and control circuitry for lunar ranging experiment
Estimation in truncated Poisson distributions with concomitant exposure intervals and truncation points
Surface interval providing safety against decompression sickness between underwater weightlessness simulation and flight altitude ascent
Sea-level pressure interval to prevent decompression sickness in humans flying in commercial aircraft after diving
Polynomials with interval coefficients, presenting Newton Raphson algorithm for real roots error bounds
Valsalva maneuver beat-to-beat effects on systolic cardiac intervals compared with time based measurements
Confidence intervals and significance tests for mean of symmetrical population with outlier observation not largest or smallest
Confidence intervals and significance tests for mean of symmetrical population with smallest or largest outlier observation
Approximate confidence interval and tests for products and ratios of binomial probabilities with application in investigating and comparing system reliabilities
Using statistical decision theory analysis to obtain predicted performance in discrimination of brief empty time intervals between auditory signals
Analysis, synthesis, and transmission of human speech based on computation of time intervals between threshold transitions of speech waveform derivatives
Viscosity and normal density measurements at lambda point intervals for pure helium-4 and helium-3 mixtures with helium-4
Limited interval definitions of photometric functions of lunar crater walls by photography from orbiting Apollo 11
A single reproducible area of the preparation in a fixed focal plane is photographically scanned at intervals during incubation. The procedure can be used for evaluating the aerobic or anaerobic growth of many microbial cells simultaneously within a population. In addition, the microscope is not restricted to the viewing of any one microculture preparation, since the slide cultures are incubated separately from the microscope.
The microminiaturization of an electronic analog signal to discrete time interval converter is presented. Discrete components and integrated circuits comprising the converter were assembled on a thin-film ceramic substrate containing nichrome resistors with gold interconnections. The finished assembly is enclosed in a flat package measuring 3.30 by 4.57 centimeters. The module can be used whenever conversion of analog to digital signals is required, in particular for the purpose of regulation by means of pulse modulation. In conjunction with a precision voltage reference, the module was applied to control the duty cycle of a switching regulator within a temperature range of -55 C to +125 C, and an input voltage range of 10V to 35V. The output-voltage variation was less than + or - 300 parts per million, i.e., less than + or - 3mV for a 10V output.
The Analog Signal to Discrete Time Interval Converter microminiaturized module was utilized to control the signal conditioner power supplies. The multi-loop control provides outstanding static and dynamic performance characteristics, exceeding those generally associated with single-loop regulators. Eight converter boards, each containing three independent dc to dc converter, were built, tested, and delivered.