Impact processes in the Solar System: New understandings through numerical modeling

A collision of two rocky objects circling the sun in space, each roughly the size and mass of a large mountain range, was modeled. A fragmentation hydrocode was developed to perform dynamical computations of collisional outcomes. Explosive framentation and fluid dynamics were used and drawn together into a single application. To model a solid, certain material parameters, such as density, elasticity, rigidity, and energies of melting and vaporization were input. These parameters are well-known for a variety of important materials, such as ice, iron, granite, and basalt. Another important parameter used is the distribution of initial flaws within the material

Contamination control concepts for space station customer servicing

The customer servicing operations envisioned for the space station, which include instrument repair, orbital replacement unit (ORU) changeout, and fluid replenishment for free-flying and attached payloads, are expected to create requirements for a unique contamination control subsystem for the customer servicing facility (CSF). Both the core space station and the CSF users present unique requirements/sensitivities, not all of which are currently defined with common criteria. Preliminary results from an assessment of the effects of the CSF-induced contamination environment are reported. Strategies for a comprehensive contamination control approach and a description of specific hardware devices and their applicability are discussed

Fibre Bundles and Generalised Dimensional Reduction

We study some geometrical and topological aspects of the generalised dimensional reduction of supergravities in D=11 and D=10 dimensions, which give rise to massive theories in lower dimensions. In these reductions, a global symmetry is used in order to allow some of the fields to have a non-trivial dependence on the compactifying coordinates. Global consistency in the internal space imposes topological restrictions on the parameters of the compactification as well as the structure of the space itself. Examples that we consider include the generalised reduction of the type IIA and type IIB theories on a circle, and also the massive ten-dimensional theory obtained by the generalised reduction of D=11 supergravity.Comment: 23 pages, Late

Structural control interaction

The basic guidance and control concepts that lead to structural control interaction and structural dynamic loads are identified. Space vehicle ascent flight load sources and the load relieving mechanism are discussed, along with the the characteristics and special problems of both present and future space vehicles including launch vehicles, orbiting vehicles, and the Space Shuttle flyback vehicle. The special dynamics and control analyses and test problems apparent at this time are summarized

Flax variety experiments at Bramley and Manjimup 1955-57

Early in 1955 it was decided to conduct flax variety trials in the higher rainfall areas of this State to determine what yields of straw and what percentage of fibre could be obtained. The first trial was conducted at Bramley Research Station and was continued for three years—the second of the series was conducted at Manjimup commencing in 1956 and continued in 1957. Details of these experiments are given below

Some recent rural radio talks.

Plantagenet peaty soils - F. E. Ryan Visitors to the south coast appreciate the colourful bottlebrush growing along the flats and many ask why this land is not used for farming. The reason is that they are part of the Plantagenet peaty sand series and these are problem soil types. These soils are very acid, sandy and peaty, they are poorly drained and may even be under water during the winter months. They contain a mass of fibrous roots in the top 8 to l0in. and this fibrous material will not rot down even when fully cultivated. The sand is greasy and does not wet easily. Even after six inches of rain the soil may have a dry band iin. below the surface even though there is a free water table five inches below. Higher grain production - H. M. Fisher There is in evidence at the present time that, in the cereal areas, falls in returns from wool can best be offset by greater emphasis on cereal grain production. This is in fact an expression of the versatile nature of farming in these areas today

Flax as a rotation crop in the higher rainfall areas of Western Australia

FLAX variety trials have been in progress at Bramley Research Station for three seasons and at Manjimup for two seasons, to determine if this crop would be a suitable cash rotation one. The results of these experiments were published earlier under the title of Flax Variety Experiment at Bramley and Manjimup, 1955-57, by Messrs. H. G. Elliott and F. E. Rya