Balloon observations of rapid variations in solar particle flux during July 1972
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Bagg, L. E.↗
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Results for “rapid”
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Rapid correction of electron microprobe data for multicomponent metallic systems
This paper describes an empirical relation for the correction of electron microprobe data for multicomponent metallic systems. It evaluates the empirical correction parameter, a for each element in a binary alloy system using a modification of Colby's MAGIC III computer program and outlines a simple and quick way of correcting the probe data. This technique has been tested on a number of multicomponent metallic systems and the agreement with the results using theoretical expressions is found to be excellent. Limitations and suitability of this relation are discussed and a model calculation is also presented in the Appendix.
Gupta, K. P.↗
Rapid method for determination of antimicrobial susceptibilities pattern of urinary bacteria
Method determines bacterial sensitivity to antimicrobial agents by measuring level of adenosine triphosphate remaining in the bacteria. Light emitted during reaction of sample with a mixture of luciferase and luciferin is measured.
Picciolo, G. L.↗
Rapid variations of balmer line strengths in the spectra of Be stars
Low resolution photoelectric spectrophotometric measurements of the first four members of the Balmer series in the spectra of one Be and five Be (shell) stars were obtained with the 92-cm telescope and image dissecting scanner. Equivalent widths were computed for each observation, and their standard deviations from the mean values were examined. Results indicate that in three of the program stars, at least one of the Balmer lines shows significant fluctuations in equivalent width. These fluctuations amount to a few per cent of total line strength and the time scales appear to be on the order of three to thirty minutes. The fluctuations are not always present in a given star, indicating that the mechanism producing them may not be continuous. The noncontinuous and nonperiodic nature of the variations, along with their short time scale suggest some form of flare-like or shock origin for the phenomenon.
Mcbeath, K. B.↗
Rapid methods for calculating radiation transport in the entry environment
A procedure is developed for the prediction of radiation transport events in the context of the entry heating environment. The equivalent-width and exponential approximations are employed to reduce the computational requirements of the governing equations. Novel features are introduced in the use of an Elsasser band model to estimate line overlapping events and in the formulation of the wall reflection events. A matrix of calculations is presented to allow an assessment of the trade-offs between accuracy and computational efforts. It is concluded that the equivalent width model allows significant savings in computational effort with only modest penalties in accuracy. Consequently, the model should be viewed as an attractive candidate for use in radiation-coupled flow field prediction procedures.
Nicolet, W. E.↗
The rapid scanning Michelson interferometer as an infrared spectrometer in astronomy
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Morgan, T. H.↗
Viscous effects in rapidly rotating stars with application to white-dwarf models. III - Further numerical results
Improved viscous evolutionary sequences of differentially rotating, axisymmetric, nonmagnetic, zero-temperature white-dwarf models are constructed using the relativistically corrected degenerate electron viscosity. The results support the earlier conclusion that angular momentum transport due to viscosity does not lead to overall uniform rotation in many interesting cases. Qualitatively different behaviors are obtained, depending on how the total mass M and angular momentum J compare with the M and J values for which uniformly rotating models exist. Evolutions roughly determine the region in M and J for which models with a particular initial angular momentum distribution can reach carbon-ignition densities in 10 b.y. Such models may represent Type I supernova precursors.
Durisen, R. H.↗
Rapid measurements of areal sensitivity and areal spectral response of photodetectors
A flying spot scanning system was used to obtain areal sensitivity and areal spectral response data for nineteen photomultipliers. The efficiency of the electron optics was shown to be dependent upon the type of dynode structure used in the several photomultipliers. From areal sensitivity measurements it was found that the relative spectral response per unit area can vary over the face of a photomultiplier.
Youngbluth, O., Jr.↗
High zonal harmonics of rapidly rotating planets
A new perturbation expansion is derived for the structure of rotating bodies in hydrostatic equilibrium. The method uses an expansion of the density on Legendre polynomial functions of angle, and can be developed analytically in a manner analogous to the standard level-surface perturbation theory. The new theory proceeds from a prescribed pressure-density relation rather than from a prescribed density distribution, and is both simpler and more physically transparent than the level-surface approach. High zonal harmonics are shown to arise via a transfer function involving derivatives of the interior sound velocity, and via mixing of multipole density components in the outer shell of the planet. Sample calculations for polytropic sequences are presented, as well as standard gravity models for Jupiter and Saturn. Mathematical subleties of the theory are discussed in an appendix.
Hubbard, W. B.↗
Application of cabin atmosphere monitors to rapid screening of breath samples for the early detection of disease states
Analysis of human breath is a nonintrusive method to monitor both endogenous and exogenous chemicals found in the body. Several technologies were investigated and developed which are applicable to monitoring some organic molecules important in both physiological and pathological states. Two methods were developed for enriching the organic molecules exhaled in the breath of humans. One device is based on a respiratory face mask fitted with a polyethylene foam wafer; while the other device is a cryogenic trap utilizing an organic solvent. Using laboratory workers as controls, two organic molecules which occurred in the enriched breath of all subjects were tentatively identified as lactic acid and contisol. Both of these substances occurred in breath in sufficient amounts that the conventional method of gas-liquid chromatography was adequate for detection and quantification. To detect and quantitate trace amounts of chemicals in breath, another type of technology was developed in which analysis was conducted using high pressure liquid chromatography and mass spectrometry.
Valentine, J. L.↗
QUICK-GEOMETRY, a rapid response method for mathematically modeling configuration geometry
The philosophy, development, and various applications of the QUICK-GEOMETRY system were outlined. This system provides a practical method for developing the geometry models that are essential to the operation of computer-based design and manufacturing systems. Of particular interest are the various methods for modeling surface geometry that are used by aerodynamic analysis codes.
Vachris, A. F., Jr.↗
Remote Sensing Application to Land Use Classification in a Rapidly Changing Agricultural/Urban Area: City of Virginia Beach, Virginia
Remote sensing data on computer-compatible tapes of LANDSAT 1 multispectral scanner imager were analyzed to generate a land use map of the City of Virginia Beach. All four bands were used in both the supervised and unsupervised approaches with the LAYSYS software system. Color IR imagery of a U-2 flight of the same area was also digitized and two sample areas were analyzed via the unsupervised approach. The relationships between the mapped land use and the soils of the area were investigated. A land use land cover map at a scale of 1:24,000 was obtained from the supervised analysis of LANDSAT 1 data. It was concluded that machine analysis of remote sensing data to produce land use maps was feasible; that the LAYSYS software system was usable for this purpose; and that the machine analysis was capable of extracting detailed information from the relatively small scale LANDSAT data in a much shorter time without compromising accuracy.
Odenyo, V. A. O.↗
Effect of hinge-moment parameters on elevator stick forces in rapid maneuvers
The importance of the stick force per unit normal acceleration as a criterion of longitudinal stability and the critical dependence of this gradient on elevator hinge moment parameters are investigated with special reference to transient effects for maneuvers of short duration. The analysis shows that different combinations of elevator parameters, which give the same stick force per unit acceleration in turns, give widely different force variations during the entries into and recoveries from steady turns and during maneuvers of short duration such as abrupt pull-ups. The stick force per unit acceleration is greater for abrupt than for gradual control movements.
Jones, R. T.↗
Linear polarimeter with rapid modulation, achromatic in the 0.3-1.1-micron range
A polarimeter is described, which provides achromatic modulation over the spectral range 0.3 to 1.1 microns, with very small light losses. The instrument is the first one to use superachromatic half-wave plates; such a plate is made of three achromatic half-wave plates of quartz and magnesium fluoride cemented with the optical axis of the central plate making an angle of 1.00 rad with the axes of the parallel-oriented outer half-wave plates. Wavelength dependence of the axis direction of the optical axis was eliminated by using two identical such plates in front of a Wollaston prism. The plate closer to the prism is stationary, while the other is continuously rotated by a stepper motor. In the polarimeter constructed, the range of instrumentally induced wavelength dependence of the plane of polarization did not exceed 0.002 rad. Using the polarimeter on a 228-cm telescope, a 10-min integration through the blue filter of the UBV photometric system for a star of magnitude 10.0 gives the percentage polarization with a mean error of + or - 0.014%.
Frecker, J. E.↗
Rapid computation of the Voigt profile
Computational procedures for evaluating the Voigt profile function with maximum relative error about one part in ten thousand are discussed. The computational region is split up into four subregions, each of which is worked on with a different computational technique (Chebyshev expansion, continued fraction expansion, 2-point Gauss-Hermite quadrature, and 4-point Gauss-Hermite quadrature). The overall procedure is designed for line-by-line transmittance calculations and similar applications, and an efficient FORTRAN IV subprogram is outlined in an appendix.
Drayson, S. R.↗
A device for rapid determination of thermophysical properties of phase-change wind-tunnel models
An experimental method for direct measurement of the thermophysical properties of wind tunnel heat transfer models was developed. The technique consists of placing the model under a bank of high intensity, radiant heaters so that the fast opening water cooled shutters, which isolate the heater bank from the model, allow a step-input heat rate to be applied. Measurements of the heat transfer rate coupled with a surface-temperature time history of the same material are sufficient to determine the material thermophysical properties. An infrared thermometer is used to measure model surface temperature and a slug calorimeter provides heat transfer rate information. The output from the infrared thermometer and calorimeter is then fed into an analog-to-digital converter which provides digitized data to a computer. This computer then calculates combined thermophysical properties and a teleprinter prints out all the data. Thus, results are available within 7 minutes of test initiation as opposed to the weeks or months required using prior techniques.
Creel, T. R., Jr.↗
High data rate performance of a BCCD for rapid scan imaging
A commercially available 1728 element shallow bulk channel CCD line array was clocked at output data rates up to 30 MHz. Temporal noise was near 200 electrons and was largely independent of clock rate. Charge transfer efficiency was in excess of 0.9999 at 30 MHz. Utilization is feasible for visual simulation and aerial mapping.
Schmieder, D. E.↗
A new rapid method of solar simulator calibration
A quick method for checking solar simulator spectra content is presented. The method is based upon a solar cell of extended spectral sensitivity and known absolute response, and a dichroic mirror with the reflection transmission transition close to the peak wavelength of the Thekaekara AMO distribution. It compromises the need for spectral discrimination with the ability to integrate wide spectral regions of the distribution which was considered important due to the spiky nature of the high pressure xenon lamp in common use. The results are expressed in terms of a single number, the blue/red ratio, which, combined with the total (unfiltered) output, provides a simple adequate characterization. Measurements were conducted at eleven major facilities across the country and a total of eighteen simulators were measured including five pulsed units.
Ross, B.↗