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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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FORTRAN 2 computer program rapidly calculates parameters of maximum likelihood estimates from sensitivity experiment data populations. The program uses the Newton-Raphson iterative procedure to calculate the mean and standard deviation of portions of the cumulative normal response function.
Laser frequency stabilization methods are based on a frequency discriminant which generates an unambiguous deviation signal used for automatic stabilization. Closed-loop control stabilizes cavity length at a null point. Some systems have a stabilized ring laser using a piezoelectric dither and others use a Doppler gain tube.
Hydrogen maser is stable short-term and long-term frequency reference for precision tracking systems. Its resettability is expressed as the rms deviation from the mean.
Desired low energy X rays are produced by modifying commercial ion tubes and combining them with standard power supplies and control circuitry. These X rays have less deviation from the solar X ray spectrum in energy and intensity.
Long-term absolute frequency stabilization of a laser oscillator is obtained when the lasers oscillation frequency is referenced to the exact center of an atomic transition. A laser amplifier acts as a discriminant to indicate when the laser frequency deviates from the center of its atomic transistion.
Tests using commercially available flowmeters provide information on the constancy in water of the calibration factor /pulses per unit volume/, on the maximum deviation of the factor from its mean value, and on the probability of predicting the calibration factor of a meter in liquid hydrogen at full scale.
As part of the programme of experimental and development work to determine the optimum demodulating techniques for communication satellite systems, three types of demodulators have been investigated at the Goonhilly earth station: 1.A conventional demodulator of the type used in 960-channel telephony or television microwave radio-relay links; 2.A frequency modulation feed-back demodulator in which the deviation of the signal is reduced before it reaches the final discriminator; and 3.A variable-bandwidth 'dynamic-tracking' demodulator in which the resonant frequency of a narrow bandwidth tuned circuit is moved rapidly to follow the nominal instantaneous frequency of the incoming signal. The conventional demodulator will not be discussed in detail here;. however, information is given on two specialized demodulators.
Validity of testing full scale flight components in transonic wind tunnel by evaluating flow deviations from free flight in critical transonic phase of flight
Centaur propellant utilization difference bridge performance in correcting deviations from desired mass ratio
Deviation of path of orbiting body calculated from nominal or reference trajectory
Hansen planetary theory representing position of disturbed planet as deviation in time and space from position of fictitious planet with Keplerian motion
Attenuation cross section at Lyman alpha for Xe deviation from Beer law indicating diatomic Xe molecule formation
Terminal guidance problem involving optimal control for deviations in systems with transport lag
Ge/Li/ drifted gamma detector for 1/2 to 10 Mev range, measuring response deviation from linearity
Deep space frequency modulation system permits transmission of data where the signal deviation is greater than 1/2 the predetection bandwidth. It provides satisfactory performance at great distances or with low signal levels.
Radiation effects on shock wave structure from stellar postshock emission spectra observations, discussing deviations from Rankine-Hugoniot relation
Polarization of He atomic radiation excited by electron impact at threshold energy, discussing deviations from theory
Wideband FM signal generation without frequency deviation or modulation frequency limitations by wave shaping FM triangular wave, discussing transmitter receiver distortion