Solutions of elasticity problems using boundary conditions obtained experimentally
Stress trajectories used to calculate stresses in irregular-shaped bodies - solutions of elasticity problems using boundary conditions
ELASTICITY↗
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Swiveling Lathe Jaw Concept for Holding Irregular Pieces
Clamp holds irregularly shaped pieces in lathe chuck without damage and eliminates excessive time in selecting optimum mounting. Interchangeable jaws ride in standard jaw slots but swivel so that the jaw face bears evenly against the workpiece regardless of contour. The jaws can be used on both engine and turret lathes.
David, J.↗
Special mandrel permits uniform welding of out-of-round tubing
Clamp holds irregularly shaped pieces in lathe chuck without damage and eliminates excessive time in selecting optimum mounting. Interchangeable jaws ride in standard jaw slots but swivel so that the jaw face bears evenly against the workpiece regardless of contour. The jaws can be used on both engine and turret lathes.
Dor, M. E.↗
Earth-orbital lifetime and satellite decay.
Orbital behavior of large irregular shaped spacecraft with life and delay prediction from laboratory tests and experiments
Benson, R. H.↗
Stochastic open channel flow.
Open channel flow studied for nonlinear effect of irregular shape and slope by Brownian motion models
Chiu, C.-L.↗
Universal router concept
Portable universal router can cut holes of large diameter and irregular shapes, machine recesses, and drill holes with certain edge-distance limitations. Rectangular and round holes may be cut without a template.
Pesch, W. A.↗
Dynamic response of viscous compressible fluids in rigid tubes
Data on experimental verification of Iberall's analysis applies to such problems as pressure sensing, pneumatic control circuits with bellows, measuring irregular shaped volumes, and transmitting fluid power by pulsating flow.
Goldschmied, F. R.↗
Moment of inertia test fixture Patent
Test fixture for measuring moment of inertia of irregularly shaped body with multiple axes
Conn, J. H.↗
Bonding of reinforced Teflon to metals
Reinforced FEP Teflon composite material is bonded to a metal substrate by applying a thin layer of copper on the metal surface and disposing irregularly shaped copper particles on the coated surface. The reinforced Teflon is then assembled in contact with the particles, and the assembly is heated under pressure at an elevated temperature below the melting point of the Teflon. A diffusion bond stronger than the reinforced Teflon component is produced, thus enabling the fabrication of self-lubricating bodies with relatively high strength.
Laiacona, F. P.↗
Lava tubes and channels in the Lunar Marius Hills.
The Marius Hills region, a volcanic plateau in Oceanus Procellarum, contains numerous rilles, rille-like structures, and chains of elongate craters. Most of these structures characteristically: (1) originate on or near irregular shaped craters associated with features previously interpreted as volcanic domes, (2) trend downslope onto Plateau Plains, (3) generally taper in width and become shallower, (4) are often discontinuous, (5) occupy the center, or apparent crest of a broad ridge, (6) may contain cut-off branches and distributary structures, and (7) may have local reversals in longitudinal slope. Structures having these characteristics are interpreted to be lava channels or partly collapsed lava tubes. Terrestrial lava tubes form exclusively, and commonly, in fluid basalt flows. Recent evidence indicates that viscosities of lunar mare 'basalt' lava flows were conducive for lava tube formation. Terrestrial analogs are offered for structures described in the Marius Hills.
Greeley, R.↗
Toward assessing the effects of crack front curvature /CFC/.
Consideration of the effect of crack front curvature (CFC) on the K calibration of five special geometries in which CFC occurs. The five cases considered include an elliptical crack in an infinite medium, an internal annular crack in a thick-walled cylinder, a through crack in a flat plate, a part-through crack in a plate, and an irregularly shaped crack in a solid. It is shown that K depends on CFC differently in each case.
Swedlow, J. L.↗
Comparative geology of crater Aratus CA (Mare Serenitatis) and Bear Crater (Idaho)
Aratus CA (lat. 24.5 N, long. 11.3 E) is an irregular-shaped crater 8.6 km long by 3 km wide in western Mare Serenitatis, which was photographed during the Apollo 15 and 17 missions. It is similar in form to Bear Crater (fig. 30-2), a small volcanic vent formed in Holocene basalt flows of the Snake River Plains, Idaho. The two features are compared and it is concluded that Aratus CA may have a geologic structure and history similar to that of Bear Crater.
Greeley, R.↗
Numerical computation of echograms in a room: Application to determination of intelligibility
Echogram recordings are used to estimate the acoustic quality of a room. Using two methods based on geometric acoustics, echograms are computed for rooms of irregular shape. The image method and the ray method have been applied to a heptahedral room as well as a conference hall. The results obtained, which have been verified experimentally, permit an estimate of the intelligibility coefficient.
Santon, F.↗
Minor planets and related objects. XIV - Asteroid /4/ Vesta
Gehrels (1967), investigating the direction of Vesta's pole, found that his light curves exhibited two distinct maxima. An analysis of all available light curves over the period from 1950 to 1973 shows that Vesta has a true period of 10h40m58s.84 (+ or - 0s.01 p.e.) with two maxima and two minima. Vesta's rotation is direct. The shape is that of a spheroid, with one diameter exceeding the other two by roughly 15%, and with an apparent shape irregularity near the south pole.-
Taylor, R. C.↗
Origin and characteristics of excess Fe metal in lunar glass welded aggregates
We show that the characteristic features of lunar glass welded aggregates including their irregular shapes, vesicularity, and content of submicron Fe metal in the welding glass can be explained by a model in which they are predominantly formed by micrometeorite impacts into the solar wind saturated topmost surface of the regolith. The Fe metal is reduced from silicates by the solar wind gases. Other possible mechanisms of Fe metal formation are discussed and shown to play at most minor roles. It is shown that surface tension forces control vesicularity and that the low gravity and high vacuum conditions prevailing on the moon are unimportant. Consequences of this surface tension control to possible lunar eruptive volcanism and to the Ar-40/Ar-39 dating of impact events are discussed.
Housley, R. M.↗
Some physical parameters of micrometeoroids
Detailed morphological parameters (depth/diameter ratio, circularity index) of microcraters in the 0.2 to 100 micron diameter range were obtained via SEM techniques for three lunar glass surfaces. The depth/diameter ratios are typically 0.5 to 0.8 with a range of 0.3 to 1.3. The circularity index varies from 0.4 to 1.0 with a pronounced maximum at 0.7 to 0.9. These parameters are compared with microcraters produced in the laboratory via electrostatic particle accelerators. The following conclusions are drawn: The great majority of observed crater depths are compatible with micrometeoroid densities of 2 to 4 g/cu cm; crater depths are incompatible for projectile densities less than 1 g/cu cm and greater than 7 g/cu cm. The circularity index of microcrater pits indicates rather equidimensional, if not spherical, projectiles. Needles, platelets and other highly irregular shapes can be excluded. Less than 5% of all craters observed may offer different conclusions.
Brownlee, D. E.↗
Self-sterilization of bodies during outer planet entry
A body encountering the atmosphere of an outer planet is subjected to heat loads which could result in high temperature conditions that render terrestrial organisms on or within the body nonviable. To determine whether an irregularly shaped entering body, consisting of several different materials, would be sterilized during inadvertent entry at high velocity, the thermal response of a typical outer planet spacecraft instrument was studied. The results indicate that the Teflon insulated cable and electronic circuit boards may not experience sterilizing temperatures during a Jupiter, Saturn, or Titan entry. Another conclusion of the study is that small plastic particles entering Saturn from outer space have wider survival corridors than do those at Jupiter.
Hoffman, A. R.↗
Self sterilization of bodies during outer planet entry
As a body encounters the atmosphere of an outer planet, whether accidentally or by plan, it will be subjected to heat loads which could result in high temperature conditions that render terrestrial organisms on or within the body non-viable. To determine whether an irregularly shaped entering body, consisting of several different materials, would be sterilized during inadvertent entry at high velocity, the thermal response of a typical outer planet spacecraft instrument was studied. The results indicate that the Teflon-insulated cable and electronic circuit boards may not experience sterilizing temperatures during a Jupiter, Saturn, or Titan entry. Another conclusion of the study is that small plastic particles entering Saturn from outer space have wider survival corridors than do those at Jupiter.
Hoffman, A. R.↗