Multiple-bubble detector
Device is segmented multiple-input detector. Bubbles are fed into each section simultaneously. Detector output is improved by using passive replicators.
George, P. K.↗
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Bias-field equalizer for bubble memories
Magnetoresistive Perm-alloy sensor monitors bias field required to maintain bubble memory. Sensor provides error signal that, in turn, corrects magnitude of bias field. Error signal from sensor can be used to control magnitude of bias field in either auxiliary set of bias-field coils around permanent magnet field, or current in small coils used to remagnetize permanent magnet by infrequent, short, high-current pulse or short sequence of pulses.
Keefe, G. E.↗
The utilization of bubble memories in defense systems
The paper considers two examples of bubble memory application: the NASA solid state data recorder for spacecraft, and the POS/8 800,000 bit recorder. A matrix chart of applications delineated by capacity and chip organization, which is primarily reflected in access time, is then presented.
Mavity, W. C.↗
Spread F bubbles - Nonlinear Rayleigh-Taylor mode in two dimensions
The paper discusses long-wavelength developed bottomside spread F which has been attributed to the Rayleigh-Taylor instability. The nonlinear saturation amplitude and the k spectrum of the inertia-dominated Rayleigh-Taylor instability is found in two directions: east-west and vertical. As in the collisional case (Chaturvedi and Ossakow, 1977), the dominant nonlinearity is found to be two-dimensional. It is found that the linearly most unstable modes, which are primarily horizontal, saturate by the nonlinear generation of vertical spatial harmonics. The harmonics are damped by diffusion or recombination. The resulting amplitude spectrum indicates that bubbles are vertically elongated in both inertial and collisional regimes.
Hudson, M. K.↗
Bubble-domain detector
Bubble domain detector employs transformer coupling for data retrieval. Method makes multidetection practical by time multiplexing. Multiplexer matrices can be scaled in 4 by 4, 4 by 8, 4 by 16, or larger combinations without diode steering.
Stermer, R. L.↗
Discovery of two distorted interstellar bubbles
During an extensive program of direct imagery of emission nebulae, arcuate structures were found around two stars. A well-defined shock-like structure was found about the T-Orionis variable LL Orionis, located to the side of the Orion Nebula. A less extensive shock-like structure was also found about the runaway star zeta Ophiuchus. These structures can best be described in terms of distorted interstellar bubbles. A direct consequence of this interpretation is an independent estimate of the rates of mass loss for these stars.
Gull, T. R.↗
Discovery of two distorted interstellar bubbles
During an extensive program of direct imagery of emission nebulae, arcuate structures have been found around two stars. A well-defined shocklike structure is found about the T Orionis variable LL Ori, located to the side of the Orion Nebula. A less extensive shocklike structure is also found about the runaway star Zeta Oph. These structures can be best described in terms of distorted interstellar bubbles. A direct consequence of this interpretation is an independent estimate of the rates of mass loss for these stars.
Gull, T. R.↗
A bubble memory module
A bubble memory module design providing flexibility for many user applications in spacecraft data recording is described. The memory module can be used with user-designed controllers with the memory organization determined by the application. Asynchronous data rates from zero to 1.33 Mbits/sec at minimum power are accomplished by using 8-chip memory cells with 100 K bit serial chips. The memory module is expandable from a 4 x 2 cell matrix to a 4 x 16 cell matrix corresponding to an expandable capacity of 6.55 M to 52.4 M bits. The module's design, utility in various memory systems, and user clocking scheme are described.
Hayes, P. J.↗
Experimental studies of the laminar separation bubble on a two-dimensional airfoil at low Reynolds numbers
The laminar separation, transition and turbulent reattachment near the leading edge of a two-dimensional NACA 663-018 airfoil were investigated using a low speed, smoke visualization wind tunnel. Lift and drag force measurements were made using an external strain gauge balance for a chord Reynolds number range of 40,000 to 400,000. An extensive flow visualization study was performed and correlated with the force measurements. Experiments were also conducted with distributed surface roughness at the leading edge and external acoustic excitation to influence the development of the airfoil boundary layer. This study delineates the effects of angle of attack and chord Reynolds number on the separation bubble characteristics and airfoil performance
Mueller, T. J.↗
An 8 x 10 to the 5th bit bubble memory cell for spacecraft applications
A multiple chip magnetic bubble memory cell design developed for NASA embodies the low power, low weight, environmental tolerance and reliability necessary for successful operation in spacecraft launch and mission environments. Packaging of multiple chips in a common magnetic bias, drive coil assembly reduces weight and volume overhead per chip and also reduces the number of coil drive components required. This 8 x 10 to the 5th bit cell is conduction cooled and provides a metal and ceramic sealed hermetic chip environment.
Becker, F. J.↗
The young Of star HD148937 and its associated interstellar bubble: H 2 region
The star HD148937 and nebulosities surrounding the star are found to be closely inter-related. IUE spectroscopy of HD148937 shows the star to be a young Of star with low mass loss. Properties Of the surrounding interstellar bubble and the H II region support the implied youth of HD148937.
Brwhweiler, F. C.↗
Pressure-Decay Measurements Improve Bubble-Point Test
Technique reduces by factor of about 100 minimum detectable flaw size in bubble-point test. By measuring rate of slow leakage, flaws as small as about 10-4 in. 2 (0.06mm2) are detected. Since technique does not require observation of screen, tests run on screens already installed inside tanks and pipes.
Silkey, J. S.↗
Interaction effects in thermocapillary bubble migration
Two bubbles migrating along their line of centers under the influence of an imposed thermal gradient are considered in the quasi-static limit. Results are reported for representative values of the governing parameters.
Meyyappan, M.↗
Resonances, radiation pressure and optical scattering phenomena of drops and bubbles
Acoustic levitation and the response of fluid spheres to spherical harmonic projections of the radiation pressure are described. Simplified discussions of the projections are given. A relationship between the tangential radiation stress and the Konstantinov effect is introduced and fundamental streaming patterns for drops are predicted. Experiments on the forced shape oscillation of drops are described and photographs of drop fission are displayed. Photographs of critical angle and glory scattering by bubbles and rainbow scattering by drops are displayed.
Marston, P. L.↗
Profiles of electrified drops and bubbles
Axisymmetric equilibrium shapes of conducting drops and bubbles, (1) pendant or sessile on one face of a circular parallel-plate capacitor or (2) free and surface-charged, are found by solving simultaneously the free boundary problem consisting of the augmented Young-Laplace equation for surface shape and the Laplace equation for electrostatic field, given the surface potential. The problem is nonlinear and the method is a finite element algorithm employing Newton iteration, a modified frontal solver, and triangular as well as quadrilateral tessellations of the domain exterior to the drop in order to facilitate refined analysis of sharply curved drop tips seen in experiments. The stability limit predicted by this computer-aided theoretical analysis agrees well with experiments.
Basaran, O. A.↗
Imaging Bubble Formation In a Drop Tube
Entire process under control of computer. Computer-controlled image-acquisition system tracks object, such as water bubble, as it moves in drop tube. Ultimately, such tracking system used to observe fusion-pellet formation in drop furnace.
Helizon, R.↗
Analysis of airfoil leading edge separation bubbles
A local inviscid-viscous interaction technique was developed for the analysis of low speed airfoil leading edge transitional separation bubbles. In this analysis an inverse boundary layer finite difference analysis is solved iteratively with a Cauchy integral representation of the inviscid flow which is assumed to be a linear perturbation to a known global viscous airfoil analysis. Favorable comparisons with data indicate the overall validity of the present localized interaction approach. In addition numerical tests were performed to test the sensitivity of the computed results to the mesh size, limits on the Cauchy integral, and the location of the transition region.
Carter, J. E.↗
The Bubble Nebula - Far-infrared and radio molecular observations of NGC 7635
The Bubble Nebula, NGC 7635, has been partially mapped at 1 arcmin resolution in the far-infrared and completely mapped at 2.2 arcmin resolution in 115-GHz emission from CO. The infrared results are consistent with the presence of only a small amount of dust within the optical part of the nebula, in agreement with previous work at visual wavelengths. The dust may be fairly uniformly spread through the H II region, although some variation in density is necessary to explain the observed temperature distribution of the dust. The CO emission is weak and the CO column density is very low, consistent with the low obscuration observed in the region. Nevertheless it is surprising that any molecules can exist in the neighbourhood of the luminous exciting star of NGC 7635 and a special geometrical configuration may be necessary.
Thronson, H. A., Jr.↗