Attainable sets and generalized geodesic spheres.
Attainable sets and generalized geodesic spheres, noting set properties and meaning of conjugate points
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Attainable sets and generalized geodesic spheres, noting set properties and meaning of conjugate points
Incompressible fluid drag force on sphere rolling at constant speed in closed-end tube
Electromagnetic scattering from adsorbing spheres near resonances calculated from extinction efficiency factor and angular scattering function dependence on refractive index
The task of removing the boundary layer by suction consists in producing, in place of the ordinary flow with the formation of vortices, another kind of flow in which the vortices are eliminated by drawing small quantities of fluid from certain points on the surface into the interior of the body. The experiments with a sphere, which constitute the subject of this report, were made early in the present year .
An algorithm for the generation of non-uniform unstructured grids on ellipsoidal geometries is described. This technique is designed to generate high quality triangular and polygonal meshes appropriate for general circulation modelling on the sphere, including applications to atmospheric and ocean simulation, and numerical weather predication. Using a recently developed Frontal-Delaunay-refinement technique, a method for the construction of high-quality unstructured ellipsoidal Delaunay triangulations is introduced. A dual polygonal grid, derived from the associated Voronoi diagram, is also optionally generated as a by-product. Compared to existing techniques, it is shown that the Frontal-Delaunay approach typically produces grids with near-optimal element quality and smooth grading characteristics, while imposing relatively low computational expense. Initial results are presented for a selection of uniform and non-uniform ellipsoidal grids appropriate for large-scale geophysical applications. The use of user-defined mesh-sizing functions to generate smoothly graded, non-uniform grids is discussed.
The Portable Apparatus for Rapid Acquisition of Bidirectional Observation of the Land and Atmosphere III (PARABOLA III) is a sphere-scanning radiometer custom designed and built by Sensit Technologies, Inc.
Portable integrating sphere for monitoring the reflectance of spacecraft coatings
Frobenius series approach to determining free spheroidal oscillations of a gravitating sphere with liquid core
Rarefied gas dynamics - heat transfer from sphere for entire range of knudsen number based on boltzmann equation
Rarefied gas dynamics - steady, axisymmetric, hypersonic flow of rarefied gas past a sphere
Rarefied gas dynamics - experimental determination of sphere drag coefficients in supersonic rarefied gas
Method of sphere-drag measurement in supersonic gas flows using low-density wind tunnel
Measurements of drag and wake structure in magneto-fluid dynamic flow about a sphere
Procedure for preparing a homogeneous, crackfree, 3.5-inch ferrite sphere needed for a satellite orientation device
Aerodynamic ablation of metal sphere at hypersonic speeds
Air damping mechanisms of circular and rectangular plates, cylinders, and spheres
Transient surface temperature distribution of thin walled sphere subjected to space radiation
Maximum model-size determination and effect of sting diameter on entry shape and sphere for low Mach number testing - Apollo spacecraft wind tunnel tests