Abstract: A method of forming a coherent acoustic beam in a marine environment includes directing each of a plurality of source nodes deployed in the marine environment to move in a respective stationary orbit, transmitting an acoustic source signal from each source node; operating a first control loop to adjust a position of each of the plurality of source nodes within the marine environment; and operating a second control loop to adjust characteristics of the acoustic source signals transmitted by each of the source nodes to form a coherent acoustic beam in the far field of a transmitting array formed by the plurality of source nodes. An acoustic beamforming system configured to operate in a marine environment is also provided.

Abstract: A smart culture vessel for holding a sample to be tested in a culture medium includes a bio-sensor, in the vessel in the culture medium with a sample, having a coating for attracting at least one pathogen expected in the sample and a detection device responsive to the bio-sensor for indicating the presence of the pathogen on the bio-sensor.

Abstract: An infra-red scanning system with raster scan display unit operating in the visible spectrum, in which the image is scanned across a linear array of detector elements to provide a signal multiplexer with electrical signals related to the detected radiation pattern. The operation of the raster scan display unit is synchronised to the operation of the scanning system so that the horizontal time base integrator is gated according to the speed of the scanning system, and the vertical time base is gated to operate in synchronism with the multiplexer in order to minimise optical distortion in the display.