Abstract
A two-phase roll cutting problem appearing in the iron and steel industry is considered in this paper. It consists of optimizing the planning of roll cutting that, for technological reasons, is effected in two phases, i.e., each raw material roll is cut into intermediate primary rolls, which in turn are cut to obtain the constituent rolls of the final product. Apart from an inherent complexity to the cutting problem resulting from the large variety of final product dimensions, other supplementary difficulties also exist. These are related to the existence of numerous restrictions involved in the whole process and the link between the two cutting phases. A heuristic was developed and tested, that is based on an automatic sequential search with defined objectives, so as to obtain a good compromise between pattern usage and trim loss, respecting the various technological impositions. Finally, a real example taken from the steel industry together with the solution obtained from a computerized version developed for microcomputers, is presented. © 1990.

Abstract
Optical fibers are used to provide object and reference illumination in the context of the electronic speckle-pattern interferometry technique. An all-fiber Michelson interferometer is used, with an electronic servo and a piezoelectric phase modulator, to obtain compensation for environmentally induced phase coupling into the fiber arms. © 1990 Optical Society of America.

Abstract
A system employing optical fibres for electronic speckle pattern interferometry is demonstrated. Single mode optical fibres are used to provide a reference beam and illumination of the object. The Michelson interferometer formed by the reference fibre and the fibre illuminating the target is used to compensate for environmentally induced phase noise. This compensation is achieved by using an electronic servo and a piezoelectric phase modulator to lock the Michelson at its quadrature point.

Abstract
An algorithm for coding image sequences based on the segmentation of the differential image into variable size and variable shape blocks is described. The differential image is split into 4 × 4 blocks, that are grouped to form square and rectangular macro blocks of several areas. Each macro block is then vector quantised. Simulation results presented show that compression rates and subjective quality compare favourably with methods previously described.

Abstract

Abstract