Automatic assembly design project 1968/9 :|breport of economic planning committee

Investigations into automatic assembly systems have been carried out. The conclusions show the major features to be considered by a company operating the machine to assemble the contact block with regard to machine output and financial aspects. The machine system has been shown to be economically viable for use under suitable conditions, but the contact block is considered to be unsuitable for automatic assembly. Data for machine specification, reliability and maintenance has been provided

Scalable iterative methods for sampling from massive Gaussian random vectors

Sampling from Gaussian Markov random fields (GMRFs), that is multivariate Gaussian ran- dom vectors that are parameterised by the inverse of their covariance matrix, is a fundamental problem in computational statistics. In this paper, we show how we can exploit arbitrarily accu- rate approximations to a GMRF to speed up Krylov subspace sampling methods. We also show that these methods can be used when computing the normalising constant of a large multivariate Gaussian distribution, which is needed for both any likelihood-based inference method. The method we derive is also applicable to other structured Gaussian random vectors and, in particu- lar, we show that when the precision matrix is a perturbation of a (block) circulant matrix, it is still possible to derive O(n log n) sampling schemes.Comment: 17 Pages, 4 Figure

New views on old hands: the context of stencils in El Castillo and La Garma Caves (Cantabria, Spain)

Hand stencils are an intriguing feature of prehistoric imagery in caves and rockshelters in several parts of the world, and the recent demonstration that the oldest of those in Western Europe date back to 37 000 years or earlier further enhances their significance. Their positioning within the painted caves of France and Spain is far from random, but responds to the shapes and fissures in the cave walls. Made under conditions of low and flickering light, the authors suggest that touch—‘palpation’—as much as vision, would have driven and directed the locations chosen for these stencils. Detailed study of the images in two Cantabrian caves also allows different individuals to be distinguished, most of whom appear to have been female. Finally, the project reveals deliberate associations between the stencils and features on the cave walls