Abstract: The disclosure provides systems and methods for data analysis of experimental data. The analysis can include reference data that are not directly generated from the present experiment, which reference data may be values of the experimental parameters that were either provided by a user, computed by the system with input from a user, or computed by the system without using any input from a user. Another example of such reference data may be information about the instrument, such as the calibration method of the instrument.

Abstract: An abrasive cleaning or cutting apparatus and method suitable particularly for underwater use at relatively low nozzle (19) overpressures (e.g. conveniently up to about 7 kg/cm.sup.2 above local hydrostatic pressure). The pressurized mixing zone (1) in which abrasive particles from hopper (3), compressed air from air-line (2), and water from water supply line (15) are mixed to form the abrasive stream is arranged such that the abrasive stream includes abrasive particles at least partially surface-wetted by the liquid entrained in air or an air liquid mist as an abrasive carrier. Preferably about 5 to 10% of the liquid is in the mist the remainder going to encapsulate the abrasive particles. The apparatus also includes valves suitably automatically actuable (in response to signals from an underwater sensor) to shut off the surface apparatus from the abrasive-carrying pipeline to restrict or prevent reverse flow in the pipeline should the mixing pressure drop at the surface.