Optical data processing
Book on optical data processing covering light characteristics, Fourier transforms, spectrum analysis, photographic film, filtering, holography, etc
Shulman, A. R.↗
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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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Comment on 'Preignition products from propellants at simulated high altitude conditions'
Engine pressure spiking restart preignition products, determining hydrazine nitrate and dinitrate presence by spectrum analysis
Dauerman, L.↗
Beam-foil studies of nitrogen
Nitrogen beam foil spectrum analysis, calculating transitions and decay times
Bashkin, S.↗
Computed and observed cyanide-radical spectra of three N stars in the infrared
N stars Y CVn, RY Dra and 19 Psc IR synthetic cyanide radical spectrum analysis, determining C 12/C 13 ratio
Fay, T. D., Jr.↗
Solar flare X-ray spectra
Solar flare X ray spectrum analysis for lower corona physical conditions, discussing continuum and line emission
Neupert, W. M.↗
Infrared spectrum of gaseous CF2 by rapid scan spectroscopy
Flash photolysis produced gaseous carbon difluoride IR spectrum analysis by rapid scan IR spectroscopy
Lefohn, A. S.↗
A pulsating X-ray source in Circinus
Circinus pulsating X ray source spectrum analysis, considering bremsstrahlung and black body models
Bowyer, S.↗
RF to digital converter
Converter can be used for automatic spectrum analysis. Automatic gain amplifier digitizes RF amplitude, and amplifier gain is measured by binary counter. Amount of gain corresponds to signal level and is proportional to count in counter. System can be used to calculate AM and FM modulation index and other parameters of pulse-modulated FM waves.
Flanders, T. E.↗
Brightness fluctuations in the K-line wings.
A power-spectrum and cross-spectrum analysis has been made of measurements of temporal fluctuations of intensity observed in the K-line wing (2.07 A from line center) and of simultaneous measurements of temporal fluctuations of Doppler displacement of the cores of 3931.122 Fe I and 3933 Ca II (K3). The measurements were made in a quiet region near the center of the sun's disk. We find that the average power spectra of the intensity fluctuations have two significant peaks of about equal strength: one at 0.0033 Hz (300-sec period); and one at about 0.001 Hz (1000-sec period). The average rms value of these intensity fluctuations is 0.0435 plus or minus 0.0082. Maximum brightness comes before maximum violet displacement of the Fe I line.
Cha, M. Y.↗
Continuous Fourier transform system
Complex digital computer is not required, only summing amplifiers and attenuators are used for transformation of signal. Continuous transform system may be used for spectrum analysis, filtering, transfer function synthesis, and communications.
Munoz, R. M.↗
Lunar Surface Gravimeter Experiment
The lunar surface gravimeter which was emplaced on the moon by the Apollo 17 flight is described and a schematic diagram of the sensor is provided. The objective of the lunar surface gravimeter is to use the moon as an instrumented antenna to detect gravitational waves. Another objective is to measure tidal deformation of the moon. Samples of signals received during lunar sunrise activity and during quiet periods are presented in graph form based on power spectrum analysis
Giganti, J. J.↗
Preliminary study of gear noise characteristics
Experimental results and conclusions are presented about the noise characteristics of gears as a function of their operating conditions. The interpretive possibilities offered by real time noise and vibration spectrum analysis are emphasized. The noise reducing effects of light weight insulation boxes are also discussed.
Gafitanu, M. D.↗
Nuclear quadrupole resonance studies in semi-metallic structures
Both experimental and theoretical studies are presented on spectrum analysis of nuclear quadrupole resonance of antimony and arsenic tellurides. Numerical solutions for secular equations of the quadrupole interaction energy are also discussed.
Murty, A. N.↗
The distribution of redshifts of radio galaxies with different optical spectra and forms
The distribution of redshifts of 222 radio galaxies has been subjected to a power-spectrum analysis. No statistically significant spectral peaks are present for galaxies showing normal absorption-line characteristics; on the other hand, significant spectral peaks are present for those exhibiting strong emission features. Of these spectral peaks, the most significant, at a wavelength of 0.031 in redshift, occurs for those strong-emission radio galaxies which are also compact. The result is consistent with the proposal suggested earlier by Burbidge that the nonrandom features, which may suggest intrinsic redshifts, are confined to those objects - QSOs, N systems, etc. - in which radiation from stars does not dominate. Possible explanations of the apparently nonrandom features are briefly discussed. Finally, a table of the most recently published small-redshift QSOs and compact emission-line galaxies is presented. The redshifts appear to conform to the 0.061 (or 0.031) periodicity found earlier.
Burbidge, G. R.↗
Periodic variation of atmospheric circulation at 14-16 days
By means of spectrum analysis of select components of the tropospheric and lower stratospheric energy cycle in the Northern Hemisphere (20 N to the pole), we are able to demonstrate the existence of a 14-16 day cycle in the atmosphere. The principal energy transfer of this cycle is the conversion from zonal available to eddy available potential energy in the troposphere. This is accompanied by an energy exchange from eddy available potential to eddy kinetic energy and thence by means of the pressure-work effect at the stratospheric boundary to the eddy kinetic energy in the stratosphere. The possible physical forcing functions of this cycle are discussed.
Miller, A. J.↗
Hard solar flare X-ray bursts on 8 December 1970
Hard X-ray bursts have been observed from two 1B flares located in the same sunspot region and separated in time by about 70 minutes on Dec. 8, 1970. The bursts are composed by many 'flashes' of 2 to 20 seconds duration. Power spectrum analysis reveals no strong periodicities although a significant peak appears at 7.5 sec. The characteristic times of 2 to 20 sec do not seem likely to be electron transit times since the flare size is so small. These times are evidently connected with the acceleration of the electrons. Fitting Takakura's model of the radio noise region to the observations, this region is found to be small, but the density of electrons above 100 keV is high, on the order of 10 million per cu cm.
Anderson, K. A.↗
Continuous Fourier transform method and apparatus
An input analog signal to be frequency analyzed is separated into N number of simultaneous analog signal components each identical to the original but delayed relative to the original by a successively larger time delay. The separated and delayed analog components are combined together in a suitable number of adders and attenuators in accordance with at least one component product of the continuous Fourier transform and analog signal matrices to separate the analog input signal into at least one of its continuous analog frequency components of bandwidth 1/N times the bandwidth of the original input signal. The original analog input signal can be reconstituted by combining the separate analog frequency components in accordance with the component products of the continuous Fourier transform and analog frequency component matrices. The continuous Fourier transformation is useful for spectrum analysis, filtering, transfer function synthesis, and communications.
Munoz, R. M.↗
Measurements of the electronic transition moments of C2-band systems
Electronic transition moments of seven C2 singlet and triplet band systems, which are in the 0.2 to 1.2 micron spectral region, have been measured. The measurements were made in emission behind incident shock waves in C2H2-argon mixtures. Narrow band-pass radiometers were used to obtain absolute measurements of shock-excited C2 radiation from which absolute electronic transition moments are derived by a synthetic spectrum analysis. New results are reported for the Ballik-Ramsay, Phillips, Swan, Deslandres-d'Azambuja, Fox-Herzberg, Mulliken, and Freymark systems.
Cooper, D. M.↗