Microslips between contacting paraboloids.
Hertz and Mindlin problems for fourth order paraboloids in contact generalized, minimizing microslips and annulus of slip
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Hertz and Mindlin problems for fourth order paraboloids in contact generalized, minimizing microslips and annulus of slip
The Southern California Earthquake Center is coordinating a effort by scientists at the Jet Propulsion Laboratory, the U.S. Geological Survey, and various academic institutions to establish a dense 250 station, continuously recording GPS geodetic array in southern California for measuring crustal deformation associated with slip on the numerous faults that underlie the major metropolitan areas of southern california.
This paper describes the test program in detail including test sample description, test procedures, and vibration test results of multiple test samples. The material pairs used in the experiment were Aluminum-Aluminum, Aluminum- Dicronite coated Aluminum, and Aluminum-Plasmadize coated Aluminum. Levels of vibration for each set of twelve samples of each material pairing were gradually increased until all samples experienced substantial displacement. Data was collected on 1) acceleration in all three axes, 2) relative static displacement between vibration runs utilizing photogrammetry techniques, and 3) surface galling and contaminant generation. This data was used to estimate the values of static friction during random vibratory motion when "stick-slip" occurs and compare these to static friction coefficients measured before and after vibration testing.
Ascending steep slopes is often a very difficult challenge for off-road vehicles, whether on Earth or on extraterrestrial bodies. This challenge is even greater if the surface consists of loose granular soil that does not provide much shear strength. This study investigated how the path at which a vehicle traverses a slope, specifically the angle that it is commanded to drive relative to the base of the hill (the angle of attack), can affect its performance. A vehicle was driven in loose sand at slope angles up to 15 degrees and angles of attack ranging from 10 to 90 degrees. A novel photogrammetry technique was implemented to both track vehicle motion and create a three-dimensional profile of the terrain. This allowed for true wheel sinkage measurements. The study showed that though low angles of attack result in lower wheel slip and sinkage, the efficiency of the vehicles uphill motion increased at higher angles of attack. For slopes up to 15 degrees, a 90 degree angle of attack provided the greatest likelihood of successful ascent.
A foamed polystyrene noise shield for microphones has been designed in teardrop shape to minimize air turbulence. The shield slips on and off the microphone head easily and is very effective in low-frequency sound intensity measurements.
Snap fasteners on each side of an electronic assembly rack blank panel give quick access to the interior. Guide pins extending from the inside face easily slip into standard screw holes on the frame and provide additional support.
Diocotron, slipping stream, instability of low density electron beams in electric and magnetic fields
Loop of flexible, small diameter, nickel wire protects metal oxide silicon /MOS/ transistors from a damaging electrostatic potential. The wire is attached to a music-wire spring, slipped over the MOS transistor case, and released so the spring tensions the wire loop around all the transistor leads, shorting them together. This allows handling without danger of damage.
The results of research programs to develop sliding electrical contact materials, both brushes and slip rings, are discussed. Problems attendant to operating sliding contacts in a vacuum are defined; limitations of commercial materials in solving these problems are described, and special materials and surface finish conditions which have resulted in solutions to these problems are presented. Data from operational tests on the newly developed materials are compared with similar data obtained from materials now used as standards in consumer products. Possible commercial applications of the more efficient sliding contact materials are discussed briefly.
Filamentary fabric made with slip-net principle principle for pressurized suits
Computerized method for on-line data analysis, elucidating SLIP language, request, processing, interpretation, time sharing, background activity, etc
Gravity and buoyancy effects on slip ratio, void fraction, flow model and boiling heat transfer
Specially-prepared foodstuffs supply an astronaut with a diet containing his basic nutritional requirements in a form that is useful in his enironment. Several edible coatings preserve foods and give loose foods form and firmness. These coatings aid in packaging and give the food slip for easy removal from the package.
Model to predict rarefied gas annular flow accounting for slip velocity and diffusion
Crystal structure and lattice parameter effects on single and polycrystalline metals adhesion, friction and wear properties, discussing basal slip hexagonal metals
Phase locked results for low SNRs pertaining to phase errors probability, cumulative and variance distribution, including time intervals between cycle-slipping
Due to its low vapor pressure, gallium, when substituted for mercury in a liquid slip ring system, transmits substantial amounts of electrical current to rotating components in an ultrahigh vacuum. It features low electrical loss, little or no wear, and long maintenance-free life.
Torque driven disconnect maintains connection on a gas supply line until desired parting occurs at a remote location. It consists of a helical plastic tube with a disconnect coupling fitted for an interference condition slip joint, and a rotationally constrained support connected to a gas source.