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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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SiC/Si diode pair provides automatic range change to extend the operating range of a logarithmic amplifier-conversion circuit and assures stability at or near the range switch-over point. the diode provides hysteresis for a trigger circuit that actuates a relay at the desired range extension point.
Multiple chip custom block, MIC construction is used to fabricate an ultracompact, low-power astable multivibrator. The design provides a multivibrator that free runs, eliminating lockup, is triggerable, pulling into synchronization with an external signal source, and permits design flexibility for controlling the frequency variations with temperature.
Latch and trip mechanisms for triggering large loads with small loads through interrupted motion
Ambient ionospheric electron density studied as triggering mechanism of auroras
Parameters affecting firing time of simultaneously triggered trigatron spark gap switches
Design of multistage triggers for digital computers and sampled-data control systems
Gas dynamic processes insufficiency for triggering transition to detonation obtained from laser schlieren records of nonsteady flow field ahead of accelerating turbulent flame
Digital period detector oscilloscope trigger for multitrace display
Imploding wire trigger technique for high shock velocity electric arc drivers in shock tubes
Photodetector triggered single pulse selection from mode locked ruby laser
Stable limit cycles and triggering limits of first radial mode in nonlinearly unstable liquid propellant rocket motors, using wave equation and Galerkin method
Triggered whistler emissions in magnetosphere, considering nonlinear interaction between whistler wave and resonating particles
Possible relationships are examined between the latitude of a discontinuity in the interplanetary magnetic field for a period prior to sudden storm commencements and the probability of sudden storm commencement-triggered negative bays.
A study of 36 storm sudden commencements (ssc) for the period June 1965 to January 1967 indicates that, for the cases considered, sufficient conditions for the triggering of simultaneous polar magnetic substorm onsets were an ssc amplitude of more than 10 gamma and an average geocentric solar magnetospheric Z component of interplanetary magnetic field of less than -1 gamma over a period of at least 1/2 hour preceding the ssc. All events satisfying these conditions produced simultaneous negative-bay onsets.
The coherent oscillations observed by Tanaka (1972) are shown to carry very high mechanical-energy fluxes of the order of 9.5 to 45 gigaergs/sq cm per sec. This energy can provide all of the energy expended in a large flare, or at least can be used to trigger a flare. The oscillations are assumed to be free modes of the sun, as described by Wolff (1972), and they are expected to be preferentially excited in the plages where large magnetic fields provide conditions favorable to rapid growth times. The energy driving the coherent oscillations may be derived from the flux deficit of sunspots in the plage.
Device provides positive triggering for inverter synchronization in uninterruptible power supplies. Integrated-circuit oscillator frequency may be higher, lower, or the same as that of the synch pulse and is always synchronized by first clock pulse.
It is suggested that the explosion of a Type II supernova triggered the collapse of a nearby interstellar cloud and led to the formation of the solar system. Estimates of the abundances resulting from nuclear processing of the supernova ejecta are presented. It appears promising that nucleosynthesis in this single supernova event can account for most isotopic anomalies and traces of extinct radioactivities in solar-system material.
The sporadic disruption of the plasma tails of some comets has recently been explained to be caused by magnetic-field-line reconnection in the cometary ionospheres due to magnetic-sector-boundary traversals. An alternative model is proposed in which the tail disruption is the end result of compression of the cometary ionosphere by high-velocity solar-wind streams, triggering the flute instability in the marginally stable tangential-discontinuity surface which separates the cometary ionosphere from the solar-wind plasma. According to the proposed model, the tail-disruption events could occur at all heliographic latitudes, whereas the Niedner-Brandt (1978) model should predict that these events are restricted to low heliographic latitudes in view of the present understanding of the sector structure of the heliosphere. Consequently, the high-latitude disruption events observed seem to present a difficulty for the latter model.