A neural network regulator for turbogenerators.

A neural network (NN) based regulator for nonlinear, multivariable turbogenerator control is presented. A hierarchical architecture of an NN is proposed for regulator design, consisting of two subnetworks which are used for input-output (I-O) mapping and control, respectively, based on the back-propagation (BP) algorithm. The regulator has the flexibility for accepting more sensory information to cater to multi-input, multioutput systems. Its operation does not require a reference model or inverse system model and it can produce more acceptable control signals than are obtained by using sign of plant errors during training I-O mapping of turbogenerator systems using NNs has been investigated and the regulator has been implemented on a complex turbogenerator system model. Simulation results show satisfactory control performance and illustrate the potential of the NN regulator in comparison with an existing adaptive controller.

Meat composition in genetically selected a control cattle from a serial slaughter experiment.

Young bulls from an Angus yearling-weight selection herd (ASl) and from the contemporary control herd (ACO), differing in average slaughter weight by 16·8%, were allocated for slaughter on one or six occasions between 7·5 and 25 months of age. The M. longissimus lumborum from the left side of each animal was measured for cholesterol, fatty acid composition, and protein, fat and ash contents in both raw and cooked samples; the pH and tenderness were also recorded. All meat was generally lean, averaging 4% fat in raw samples and 2·4% fat in cooked samples. There was a trend, though not significant, for a slightly lower percentage of fat at a fixed age in raw and cooked meat from the AS] herd than from the A CO herd. There were no significant selection effects on cholesterol content or fatty acid content, in either raw or cooked meat samples. The pH was significantly, higher in meat from the ASl than the A CO herd, although the difference was small (0·11 units), and there were no significant herd differences in tenderness. Overall, the herd effects on chemical composition and tenderness were very small and unlikely to be detected by consumers.

Carcass composition and meat quality of brush-tail possums (Trichosurus vulpecula).

One-hundred-and-thirty-nine possums, balanced as far as possible for sex (68 male, 71 female) and age (1 year, 42; 2-4 years, 61; 5+ years, 36), were slaughtered and the dissected carcass composition, muscle, and cooked meat composition measured. Possums were slaughtered at time in captivity TIC 0 (n = 58), TIC 14 days (n = 20) and TIC 28 days (n = 61). Compared with the 5+ years (mature) age group the 1 year olds (juveniles) were 67% and the 2-4 year olds (immature) 96% of the live weight of the mature possums. Carcass composition was characterised by high lean (78-80%) and low fat (around 1-2%). The cooked meat from possums is very high in protein (∼ 25%) and low in fat, suggesting it should be a valuable source of animal protein with a low total fat, high unsaturated fat content. In all cases cooked meat was rated as tender, based on shear force values, despite having a pH of around 6·3.