Developing a census data-mapping package for Sirius]

This paper describes the development of a census data-mapping package for the Sirius microcomputer. The major objective was to display data from the 1981 United Kingdom Census Small Area Statistics onto various map bases for use in published reports and for interactive comparisons among census variables     

The pulse distributed file system

A network of powerful personal computers, linked by a high-speed local area network, is being seen increasingly as an alternative to a traditional centralized time-sharing operating system. The PULSE project is investigating how such a system may be constructed to give the benefits of a self-sufficient personal computer to each user without losing the facilities for communication and sharing of data inherent in centralized systems. In particular, a distributed file system has been built which provides a single global UNIX

1 UNIX is a trademark of Bell Laboratories.

-like hierarchy, with a consistent appearance when accessed from any machine. Replicated copies of files are maintained to improve reliability, increase performance, and enable each machine to run stand-alone, albeit with reduced facilities.     

A study of behavioural groupings of polyphenolic species in "fino" sherry wine. Evolution during vinification and mechanical treatment of the grape

The different groups and/or classes among phenolic acids and aldehydes identified during the elaboration process of "fino" sherry wine have been studied. The study was carried out using different processes during the elaboration of the wine and we have attempted to establish whether the different treatments of the grape affect these groupings. The study was undertaken by means of cluster and multifactorial analysis on the data obtained by the quantitative determination of phenolic acids and aldehydes during vinification and in experiments carried out on the grape under different mechanical treatments. The analysis of phenolic acids and aldehydes was done with HPLC, using a C-18 mu-Bondapak and a stepwise composite gradient. The samples were previously extracted with ethylic ether.     

The induction of preferred orientation in a liquid crystal co-polyester by extrusion and drawing

It is shown that liquid crystal polyester can be extruded and drawn from the melt into fine fibres which possess stiffnesses up to 68 GPa. Thicker fibres with smaller draw ratios have correspondingly lower stiffnesses, which are correlated with molecular alignments characterized by flat plate X-ray diffraction. Fibres with a range of diameters were heat-treated over a range of temperatures to determine the effect of annealing on preferred orientation and stiffness. Heat-treatment of as-spun fibres produced maxima in axial stiffness at 170° C, corresponding to an increase in preferred orientation, and 270° C, corresponding to the development of quasi-crystalline order which is analysed. Scanning electron microscopy showed the existence of needle-like domains of approximately circular cross section up to 0.8 m in diameter. These were aligned in the direction of drawing in contrast to being haphazardly arranged in a hot rolled specimen displaying no preferred orientation.     

An algorithm for solving sparse Nonlinear Least Squares problems

We introduce a new method for solving Nonlinear Least Squares problems when the Jacobian matrix of the system is large and sparse. The main features of the new method are the following:

1. The Gauss-Newton equation is “partially” solved at each iteration using a preconditioned Conjugate Gradient algorithm.
2. The new point is obtained using a two-dimensional trust region scheme, similar to the one introduced by Bulteau and Vial.

We prove global and local convergence results and we present some numerical experiments.