Active cavity radiometric scale, international pyrheliometric scale, and solar constant
Active cavity radiometric and international pyrheliometric scales comparison and solar constant from simultaneous solar irradiance measurements
Willson, R. C.↗
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Perturbation analysis and constants for the red system of the cyanide radical
CN radical red system molecular constants, considering degenerate perturbation effects in shifts between electronic states
Fay, T.↗
Measurements of the duration of constant reflected-shock temperature in a reflected shock tunnel
Carbon dioxide IR radiation measurements of duration of constant reflected shock temperature in overtailored shock tunnel
Monson, D. J.↗
Simplification in the computation of the sensitivity functions for constant coefficient linear systems
Constant coefficient linear systems sensitivity functions computational procedure using nth order differential equations linear transformations
Denery, D. G.↗
Relativistic gravity in the solar system. II - Anisotropy in the Newtonian gravitational constant
Relativistic gravity in solar system, predicting Newtonian gravitational constant anisotropy measurements by Cavendish experiments
Will, C. M.↗
Analysis of an experiment to determine the gravitational constant in an orbiting space laboratory
Experimental determination of gravitational constant in orbiting space laboratory by gravitational centrifugal balance of test objects
Vinti, J. P.↗
Radiation scales on which standard values of the solar constant and solar spectral irradiance are based
The question of radiation scales is critically examined. There are two radiation scales which are of fundamental validity and there are several calibration standards and radiation scales which have been set up for practical convenience. The interrelation between these scales is investigated. It is shown that within the limits of accuracy of irradiance measurements in general and solar irradiance measurements in particular, the proposed standard values of the solar constant and solar spectrum should be considered to be on radiation scales of fundamental validity; those based on absolute electrical units and on the thermodynamic Kelvin temperature scale.
Thekaekara, M. P.↗
Proposed specification for the solar constant and air mass zero solar spectral irradiance
The specification defines the solar constant and the zero air mass solar spectral irradiance for use in thermal analysis, thermal balance testing, and other tests of spacecraft and spacecraft components and materials. It is based upon data from experimental measurements made from high altitude aircraft, balloons, spacecraft, and the earth's surface. The stated accuracies are based on the estimated accuracies of the measurements, calibrations, and radiometric scales.
Source record↗
End-to-end RMS error testing on a constant bandwidth FM/FM system
End-to-end root-mean-square (rms) tests performed on a constant bandwidth FM/FM system with various settings of system parameters are reported. The testing technique employed is that of sampling, digitizing, delaying, and comparing the analog input against the sampled and digitized corresponding output. Total system error is determined by fully loading all channels with band-limited noise and conducting end-to-end rms error tests on one channel. Tests are also conducted with and without a transmission link and plots of rms errors versus receiver signal-to-noise (S/N) values are obtained. The combined effects of intermodulation, adjacent channel crosstalk, and residual system noise are determined as well as the single channel distortion of the system.
Wallace, G. R.↗
Environmental simulation from 0.01 to 100 solar constants
The design and development of two solar radiation simulators with an intensity variation ranging from 0.01 to greater than 100 solar constants under vacuum conditions are discussed. The characteristics of the simulators are presented in terms of spectral content, beam uniformity, and stability. Preliminary thermal radiative property data obtained at high temperatures are reported. The general operating characteristics of the simulator are automatic starting, control of both positive and negative electrodes, and uninterrupted operation for periods in excess of 24 hours.
Jack, J. R.↗
Calculation of trajectories using constant and slowly varying functions
A method is presented for calculating trajectories for the restricted problem of three bodies which utilizes conic propagation of the state vector with frequency correction of position and velocity by means of a constant or slowly varying function. This method of calculating trajectories was applied to the planar circular restricted three body problem, the planar elliptic restricted problem, and the ephemeral restricted problem. Two methods (the refined method and the straight forward method) of determining the direction of the position correction are presented for the circular restricted problem and the elliptic restricted problem of three bodies. Only the straight forward method was used with the ephemeral restricted problem. The earth, the moon, and a space vehicle comprise the restricted three body model that is used.
Culpepper, B. K.↗
Variational solutions by the use of stepwise constant functions. I - Linear case.
Demonstration that accurate solutions to the integral equation or to the extremal function can be easily obtained by the variational method in many cases when a stepwise constant function is used for the trial function. The evaluation procedure is simple and straightforward; integrals of the kernel function can be evaluated analytically; the method provides, when the solution involves singularities, the best mean value across the singularity; the results are accurate in both the detailed physical quantities and their averages; the resultant solution can be further integrated analytically over the parameters associated with the problem; and the method can be readily applied to nonlinear integral equations.
Yoshikawa, K. K.↗
Photodetachment of an electron from selenide ion - The electron affinity and spin-orbit coupling constant for SeH.
The relative cross section for the gas phase photodetachment of an electron from SeH(-) was determined in the wavelength region 428 to 578 nm. An ion cyclotron resonance spectrometer was used to generate, trap, and detect the negative ions, and a 1000-W xenon arc lamp with a grating monochromator was employed as the light source. The cross section exhibited two sharp thresholds, whose positions remained unchanged for the photodetachment of SeD(-). As a result of these thresholds, the electron affinity and the spin-orbit coupling constant were evaluated.
Smyth, K. C.↗
Theory of an experiment in an orbiting space laboratory to determine the gravitational constant.
An experiment is discussed for determining the gravitational constant with the aid of an isolated system consisting of an artificial satellite moving around an artificial planet. The experiment is to be conducted in a spherical laboratory traveling in an orbit around the earth. Difficulties due to the gravity-gradient term are considered, and the three-tunnel method proposed by Wilk (1969) is examined. The rotation of the sphere is discussed together with aspects of the reference systems used, the equations of motion of the spacecraft and of the test objects, the field from the earth's gravity gradient at the test object, higher harmonic terms in the gravity gradient force, gravitational effects of the spacecraft itself, and a computer simulation.
Vinti, J. P.↗
Characteristics and constants of motion method for collisional kinetic equations.
The Lagrange characteristics method and the constants of motion method are applied to various collisional kinetic equations. The relationship between the characteristics and the particle equations of motion is discussed. A special solution of Chandrasekhar equation is given.
Cap, F. F.↗
Minimizing the area required for time constants in integrated circuits
When a medium- or large-scale integrated circuit is designed, efforts are usually made to avoid the use of resistor-capacitor time constant generators. The capacitor needed for this circuit usually takes up more surface area on the chip than several resistors and transistors. When the use of this network is unavoidable, the designer usually makes an effort to see that the choice of resistor and capacitor combinations is such that a minimum amount of surface area is consumed. The optimum ratio of resistance to capacitance that will result in this minimum area is equal to the ratio of resistance to capacitance which may be obtained from a unit of surface area for the particular process being used. The minimum area required is a function of the square root of the reciprocal of the products of the resistance and capacitance per unit area. This minimum occurs when the area required by the resistor is equal to the area required by the capacitor.
Lyons, J. C.↗
Determination of Optical Constants of in Bi from Reflectance Measurements
A fall in reflectance was noted from values obtained for a freshly cleaved sample to values obtained after periods of exposure of the surface to air. The decrease in reflectance with increased exposure time is attributed to formation of a surface layer insoluble in Freon or ethyl alcohol; it is assumed to be a tarnish layer. Computer processing was employed to calculate optical constants from reflectance data.
Martin, F. E.↗
An analytical study of the response of a constant-attitude aircraft to atmospheric turbulence
A light airplane equipped with an automatic control system which drives large wing flaps and the stabilator so as to produce a constant pitch attitude in all flight modes was analyzed for its response to a specific gust. The aircraft was also equipped with a bank-angle steering, zero sideslip automatic control system which was studied for its effectiveness in suppressing a specific lateral gust. The gusts were assumed to be comprised of 200 lateral and 400 vertical sinusoids. Each was used to excite the controlled aircraft and the time response to the sum of all sinusoids was plotted. The assumption was that the gust may be treated as stationary in space but variable in time rather than the reverse. Results indicate that such a control system can suppress vertical gusts up to the limit of control authority. Either the lateral accelerations or the yawing velocity response to lateral gusts can be suppressed with this system but not both simultaneously.
Smetana, F. O.↗