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Stepping motor control circuit Patent
Stepping motor control apparatus exciting windings in proper time sequence to cause motor to rotate in either direction
Supersonic combustion of hydrogen in a vitiated air stream using stepped wall injection
Combustion physics and ignition of hydrogen in supersonic stream of vitiated air or inert gases using stepped-wall injection procedure
Analytic study of an electric stepping motor drive for a nuclear reactor control drum
Performance of electric stepping motor as reactor control drum drive
Pressure distributions on a cylindrical surface behind shallow three-dimensional rearward-facing steps at Mach numbers from 0.4 to 1.3
Wind tunnel investigation of static pressure distributions along cylindrical surface behind shallow, three dimensional, rearward facing step of various heights
NASTRAN Installation: Implementation Steps and Possible Problems Encountered
NASTRAN, from its inception, was designed to operate on several diverse computer system. It is currently installed and operating on the CDC 6600, the IBM 360, and the UNIVAC 1108. This paper discusses the steps found by CSC to be necessary in installing NASTRAN on a computer system and the possible obstacles that might be encountered in undertaking NASTRAN installation. Reference is made to actual problems that arose during installation on the above machines. With a knowledge of what has happened to date in setting up NASTRAN, the future user will be better able to cope with and understand the implications of installing NASTRAN on his computer.
Dynamic response and stability of a gas-lubricated Rayleigh-step pad
Dynamic response of gas lubricated thrust bearing with shrouded Raleigh-step pads
Experiments on the stability of water-lubricated Rayleigh step hydrodynamic journal bearings at zero load
Performance tests of water-lubricated, Rayleigh step, hydrodynamic journal bearings under no load conditions to determine stability
Separation of a supersonic turbulent boundary layer by a forward facing step
Supersonic turbulent boundary layer separation on flat plate by forward facing step, measuring mean flow field characteristics
A partial-step algorithm for enlarging the convergence region of the nonlinear estimation problem
Weighted least squares nonlinear estimation problem, presenting partial step algorithm for convergence region enlargement
A refined step-recovery technique for measuring minority carrier lifetimes and related parameters in asymmetric p-n junction diodes
Forward biased asymmetric p-n junction diodes with arbitrary impurity distributions, measuring minority carrier lifetimes by refined step recovery technique
Supersonic combustion of hydrogen in a vitiated air stream using stepped-wall injection
Supersonic hydrogen combustion in vitiated air stream with stepped wall injection, considering temperature, pressure and composition measurements
Nonlinear response of gas-lubricated shrouded Rayleigh-step thrust pad
Quasi-static pressure characteristics of gas lubricated thrust bearing with shrouded Rayleigh step pads, solving nonlinear equation of motion
Effects of loading sequence for notched specimens under high-low two-step fatigue loading
The effects of loading sequence on crack-initiation period were investigated for notched aluminum-alloy specimens under high-low two-step loading with special emphasis on local cyclic stresses and strains at the notch root. Local stress and strain were determined by a procedure based on an equation proposed by Neuber which relates elastoplastic stress and strain at a notch. Local stress and strain were also measured experimentally to verify the Neuber equation. The effects of initial high load on the crack-initiation periods were demonstrated with notched specimens and were simulated in unnotched specimens fatigue tested with local stress sequences. An analysis of the results indicated that sequence effects were not caused solely by local residual stresses, as is usually assumed; the existence of a damaging effect, resulting from the high local strain cycles, was demonstrated. The sequence effects observed with notched specimens were interpreted as the combined result of residual stresses and high local strain cycles.
Electric-stepping-motor tests for a control-drum actuator of a nuclear reactor
Experimental tests were conducted on two stepping motors for application as reactor control-drum actuators. Various control-drum loads with frictional resistances ranging from approximately zero to 40 N-m and inertias ranging from zero to 0.424 kg-sq m were tested.
A variable-step-size robust delta modulator.
Description of an analytically obtained optimum adaptive delta modulator-demodulator configuration. The device utilizes two past samples to obtain a step size which minimizes the mean square error for a Markov-Gaussian source. The optimum system is compared, using computer simulations, with a linear delta modulator and an enhanced Abate delta modulator. In addition, the performance is compared to the rate distortion bound for a Markov source. It is shown that the optimum delta modulator is neither quantization nor slope-overload limited. The highly nonlinear equations obtained for the optimum transmitter and receiver are approximated by piecewise-linear equations in order to obtain system equations which can be transformed into hardware. The derivation of the experimental system is presented.
Heat transfer at reattachment of a compressible flow over a backward facing step with a suction slot.
A simplified model is suggested for engineering estimates of heat transfer in the vicinity of reattachment for the case of supersonic flow over a backward facing step with a suction slot. The presented approach gives a closed-form approximate solution which is shown to be in satisfactory agreement with experimental results for the case of no mass transfer, and is expected to predict the effect of mass transfer in the case of suction.
Single step detection of blurred images in a coherent optical processor.
Two important operations that can be performed by coherent optical processing systems are image detection and image restoration. These operations require complex spatial filters, and if both operations are to be performed, cascaded processing stages employing two separate spatial filters are usually needed. Spatial filters are described that will perform in a single step both operations simultaneously, thus eliminating the need for extra processing stages while providing the advantages of higher efficiency and smaller space requirements. The filters are characterized by their simplicity and are easily fabricated using conventional techniques. Experimental results are presented.