Abstract: The present disclosure generally relates to user interfaces for health monitoring. Exemplary user interfaces for initial setup of health monitoring using a first electronic device and a second electronic device is described. Exemplary user interfaces for recording biometric information for use in health monitoring is described. Exemplary user interfaces for using an input device while recording biometric information for health monitoring is described. Exemplary user interfaces for viewing and managing aspects of health monitoring is described.

Abstract: The present invention relates to control of engine variable of a gas turbine engine to regulate the surge margins of at least two compressors. A controller (20) receives data measured from engine sensors (22, 23) and uses said data to determine an indication of surge margin for each of at least two compressors (6, 7) of the gas turbine engine. The controller (20) uses the indications of surge margin for each of the compressors to determine a control strategy that balances the requirements of each compressor. In one embodiment a surge margin operating map divided into different control domains (40, 43, 43) is used. The indication of surge margin determined for each compressor is plotted to determine which control domains the current operating point on the surge margin operating map falls within.

Abstract: Switching circuitry comprising a bank of actuatable switches connected in parallel between a supply terminal and a decoding terminal, each switch being connected in series with a component which, when the switch is actuated, applies to the second terminal an analog signal having a value unique to that switch.

Abstract: The present invention relates to control of engine variable of a gas turbine engine to regulate the surge margins of at least two compressors. A controller (20) receives data measured from engine sensors (22, 23) and uses said data to determine an indication of surge margin for each of at least two compressors (6, 7) of the gas turbine engine. The controller (20) uses the indications of surge margin for each of the compressors to determine a control strategy that balances the requirements of each compressor. In one embodiment a surge margin operating map divided into different control domains (40, 43, 43) is used. The indication of surge margin determined for each compressor is plotted to determine which control domains the current operating point on the surge margin operating map falls within.

Abstract: Switching circuitry comprising a bank of actuatable switches connected in parallel between a supply terminal and a decoding terminal, each switch being connected in series with a component which, when the switch is actuated, applies to the second terminal an analog signal having a value unique to that switch.

Abstract: A method for operating a multi-stage combustor of a gas turbine engine comprises: (a) determining a combustor air entry temperature; (b) determining the combustor air entry flow rate; and (c) controlling the fuel split ratio to stages of the combustor on the basis of the combustor air entry flow rate and the combustor air entry temperature.