Measurement and Control

West, John C.

doi: 10.1177/002029406900200103pmid: N/A

The equivalent gain concept of a mono-variable non-linear stochastic process is used to evaluate the linear matrix equivalent of a multi-variable non-linearity having n independent inputs and m outputs.It is shown that if the n inputs are restricted to separable class of processes (which includes Gaussian random signals and also sinusoidal wave forms but is much wider), then the distortion terms produced by the non-linearity and by cross modulation have zero cross-correlation with any of the input signals.

Jacobs, O. L. R.

doi: 10.1177/002029406900200104pmid: N/A

The paper describes a digital computer simulation of a class of discrete-time, single-input, stepping extremum control systems with input disturbance and output measurement noise and with an easily instrumented control law. The results of the simulation provide both design equations and quantitative information about the best results that can be achieved with the class of systems considered. Two features of the simulation that are of interest are an automatic procedure that is used to reduce statistical errors to a specified level, and the use of dimensional analysis to reduce the number of variables that need be considered to two.

Inskip, B.; Salmon, J. D.

doi: 10.1177/002029406900200101pmid: N/A

Lush, L. A.

doi: 10.1177/002029406900200102pmid: N/A

The paper gives a résumé of events leading up to the decision by the Gas Industry in this country to convert from one based on manufactured Town Gas to one entirely based on Natural Gas. The importation of liquefied natural gas, North Sea exploration, the laying of pipelines under the sea and the principal ‘feeders’ are briefly mentioned. Some of the planning aspects of conversion are discussed with particular reference to the conversion programme for selected industry in Sheffield.