Abstract: A multi-stage oxygenator includes a submerged fluid-tight pressure vessel that has first, second, and third sections. A baffle divides the second section into compartments, and a water delivery mechanism delivers water into the second section via the first section. An interface between the first and second sections delivers water to the compartments as water jets or droplets, creating flooded zones. A gas delivery mechanism delivers oxygenated gas into a compartment to create a gas void, through which the water jets or droplets fall, between its flooded zone and the first section. A gas connection through the baffle allows gas from the compartment to create another gas void in a subsequent compartment in series therewith. A gas release device maintains the gas voids by releasing gas from a last compartment. The third section connects the compartments allowing water from their flooded zones to mix to produce treated water that is outputted.

Abstract: Techniques for performing fine-scale movement tracking of underwater objects are described. A computing device or system may receive timestamps corresponding to acoustic signals detected using an underwater acoustic receiver. The device or system may select a period of a known acoustic transmitter, and generate raw image data plotting the timestamps as graphical elements with respect to a first axis corresponding to linear time, and a second axis having a magnitude corresponding to the selected period. A first machine learning (ML) model may process the raw image data to generate segmented image data include a subset of the graphical elements determined to correspond to the selected period. A portion of the segmented image data, including the graphical elements, may be input to a second ML model to generate image data comprising a subset of the graphical elements corresponding to the selected period.

Abstract: An aquaculture pen includes an annular floatation assembly formed from a plurality of float platforms connected end to end. A weight ring is suspended from the floatation assembly by a first plurality of tension members at a central portion of the float platforms. A net support ring is suspended from the floatation assembly by a second plurality of tension members that are attached to the floatation assembly, for example, outboard of the first plurality of tension members. A mesh enclosure for the pen includes a main portion attached to the net support ring, a jump net portion that extends from the net support ring to engage the inboard side of the floatation assembly, and a top portion that closes an upper end of the mesh enclosure.

Abstract: A low head oxygenator system includes one or more chambers, each of the one or more chambers having an open top and one or more distribution plates, each distribution plate disposed over the open top of a corresponding one of the one or more chambers. Each of the one or more distribution plates has a predetermined number of orifices uniformly distributed within one or more zones of the respective distribution plate and no orifices in at least one remaining zone of the respective distribution plate. The oxygenator system further includes a container, disposed on top of the one or more distribution plates, and configured to allow a liquid contained in the container to flow through the orifices of the one or more distribution plates into the one or more chambers. Further, use of the distribution plate frees up the head-space region for a scrubbing insert configured to perform stripping.

Abstract: A low head oxygenator system includes one or more chambers, each of the one or more chambers having an open top, and one or more distribution plates, each distribution plate disposed over the open top of a corresponding one of the one or more chambers. Each of the one or more distribution plates has a predetermined number of orifices distributed within one or more zones of the respective distribution plate and no orifices in at least one remaining zone of the respective distribution plate. The oxygenator system further includes a container (e.g. trough), disposed on top of the one or more distribution plates, and configured to allow a liquid contained in the container to flow through the orifices of the one or more distribution plates into the one or more chambers.

Abstract: A low head oxygenator system includes one or more chambers, each of the one or more chambers having an open top, and one or more distribution plates, each distribution plate disposed over the open top of a corresponding one of the one or more chambers. Each of the one or more distribution plates has a predetermined number of orifices distributed within one or more zones of the respective distribution plate and no orifices in at least one remaining zone of the respective distribution plate. The oxygenator system further includes a container (e.g. trough), disposed on top of the one or more distribution plates, and configured to allow a liquid contained in the container to flow through the orifices of the one or more distribution plates into the one or more chambers.

Abstract: Techniques for performing fine-scale movement tracking of underwater objects are described. A computing device or system may receive timestamps corresponding to acoustic signals detected using an underwater acoustic receiver. The device or system may select a period of a known acoustic transmitter, and generate raw image data plotting the timestamps as graphical elements with respect to a first axis corresponding to linear time, and a second axis having a magnitude corresponding to the selected period. A first machine learning (ML) model may process the raw image data to generate segmented image data include a subset of the graphical elements determined to correspond to the selected period. A portion of the segmented image data, including the graphical elements, may be input to a second ML model to generate image data comprising a subset of the graphical elements corresponding to the selected period.

Abstract: A low head oxygenator system includes one or more chambers, each of the one or more chambers having an open top and one or more distribution plates, each distribution plate disposed over the open top of a corresponding one of the one or more chambers. Each of the one or more distribution plates has a predetermined number of orifices uniformly distributed within one or more zones of the respective distribution plate and no orifices in at least one remaining zone of the respective distribution plate. The oxygenator system further includes a container, disposed on top of the one or more distribution plates, and configured to allow a liquid contained in the container to flow through the orifices of the one or more distribution plates into the one or more chambers. Further, use of the distribution plate frees up the head-space region for a scrubbing insert configured to perform stripping.

Abstract: A low head oxygenator system includes one or more chambers, each of the one or more chambers having an open top, and one or more distribution plates, each distribution plate disposed over the open top of a corresponding one of the one or more chambers. Each of the one or more distribution plates has a predetermined number of orifices distributed within one or more zones of the respective distribution plate and no orifices in at least one remaining zone of the respective distribution plate. The oxygenator system further includes a container (e.g. trough), disposed on top of the one or more distribution plates, and configured to allow a liquid contained in the container to flow through the orifices of the one or more distribution plates into the one or more chambers.

Abstract: A submersible aquaculture pen includes a mesh enclosure supported by an annular floatation collar in a body of water. A weight ring is suspended from the floatation collar with a first plurality of cables. A variable buoyancy assembly is operable to selectively transition the aquaculture pen between a floating configuration and a submerging configuration. The variable buoyancy assembly includes a plurality of connected bell jars that are closed at a top end and are open at a bottom end. An air supply system is configured to selectively inject a controlled amount of air into each of the connected bell jars.

Abstract: Techniques for reducing biofouling on optical equipment, using minimum power in a marine environment are provided. An example apparatus for reducing biofouling in a marine environment includes a housing including a cavity and a convex ultraviolet transparent window disposed over the cavity, an optical device disposed in the cavity and directed towards the convex ultraviolet transparent window, one or more ultraviolet light emitting diodes disposed in the cavity and directed toward the convex ultraviolet transparent window, and a controller operably coupled to the one or more ultraviolet light emitting diodes and configured to provide at least one lamp power function to the one or more ultraviolet light emitting diodes, wherein the at least one lamp power function is based on at least a flash power value, a flash duration, and a rest duration.

Abstract: A mort trap assembly includes an upper ramp with a top end, a first bottom end, and an outer edge that is fixedly attached to an inner edge of a slide. A retaining chamber is located below the upper ramp and includes a first entry port located below the first bottom end of the upper ramp. A lower ramp has a top end spaced away from the upper ramp, and a first bottom end located at a bottom of the first entry port of the retaining chamber, and a purge pipe fluidly connected to the retaining chamber. The upper ramp is configured to receive morts from the slide, and the lower ramp is configured to receive the morts from the upper ramp and to direct the received morts into the first entry port.

Abstract: An underwater camera system for monitoring fish in a fish pen is described. A stereoscopic camera may be used to determine dimensions of fish, and the underwater camera system may use the fish dimensions to estimate a biomass value of fish within the fish pen. The biomass value and rates of change of the biomass value may be used to adjust feeding of the fish in the fish pen. Images captured by the stereoscopic camera may be used to focus a variable focal lens camera on a fish to obtain high-resolution images that can be used for diagnosing fish conditions. Images captured by the stereoscopic camera may be used to predict motion of the fish, and the predicted motion may be used to generate various fish monitoring analytic values. The fish monitoring analytic values may be used to automatically control operation of the fish pen.

Abstract: In some embodiments, an underwater camera system for monitoring fish in a fish pen is provided. In some embodiments, a stereoscopic camera may be used to determine dimensions of fish, and the underwater camera system may use the fish dimensions to estimate biomass of fish within the fish pen. The biomass value and rates of change of the biomass value may be used to adjust feeding of the fish in the fish pen. In some embodiments, images captured by the stereoscopic camera may be used to focus a variable focal lens camera on a fish to obtain high-resolution images that can be used for diagnosing fish conditions. In some embodiments, images captured by a camera may be used to predict motion of the fish, and the predicted motion may be used to generate various fish monitoring analytic values. The fish monitoring analytic values may be used to automatically control operation of the fish pen.

Abstract: A fish feed dispersing apparatus includes a helical dispersing tube attached to a fish pen with a mounting assembly. The helical dispersing tube has an inlet end that receives fish feed from a source, and includes a number of spaced apertures that disperse the received fish feed. A mounting assembly supports the dispersing tube, and includes two spaced-apart attachment members connected by a plurality of elongate members, and a plurality of hanger subassemblies. Each hanger subassembly has a first end attached to one of the elongate members and a second end that includes a clamp configured to engage the helical dispersing tube. The hangar assemblies are adjustable, and support the helical dispersing tube during use.

Abstract: An aquaculture pen includes an annular floatation assembly formed from a plurality of float platforms connected end to end. A weight ring is suspended from the floatation assembly by a first plurality of tension members at a central portion of the float platforms. A net support ring is suspended from the floatation assembly by a second plurality of tension members that are attached to the floatation assembly, for example, outboard of the first plurality of tension members. A mesh enclosure for the pen includes a main portion attached to the net support ring, a jump net portion that extends from the net support ring to engage the inboard side of the floatation assembly, and a top portion that closes an upper end of the mesh enclosure.

Abstract: A mort trap assembly includes an upper ramp with a top end, a first bottom end, and an outer edge that is fixedly attached to an inner edge of a slide. A retaining chamber is located below the upper ramp and includes a first entry port located below the first bottom end of the upper ramp. A lower ramp has a top end spaced away from the upper ramp, and a first bottom end located at a bottom of the first entry port of the retaining chamber, and a purge pipe fluidly connected to the retaining chamber. The upper ramp is configured to receive morts from the slide, and the lower ramp is configured to receive the morts from the upper ramp and to direct the received morts into the first entry port.

Abstract: A fish feed dispersing apparatus includes a helical dispersing tube attached to a fish pen with a mounting assembly. The helical dispersing tube has an inlet end that receives fish feed from a source, and includes a number of spaced apertures that disperse the received fish feed. A mounting assembly supports the dispersing tube, and includes two spaced-apart attachment members connected by a plurality of elongate members, and a plurality of hanger subassemblies. Each hanger subassembly has a first end attached to one of the elongate members and a second end that includes a clamp configured to engage the helical dispersing tube. The hangar assemblies are adjustable, and support the helical dispersing tube during use.

Abstract: A mortality trap (150) for a spar buoy fish pen (100) is configured to receive and trap deceased fish, or morts (M), that sink from the fish pen. The mortality trap attaches to a lower portion of the spar buoy (110) to define a first passage (90). The sinking mort passes into an upper receiver portion (150U) of the mortality trap, and encounters a sloping transverse panel (154). Gravity causes the mort to continue through a second passage (B) into a lower entrapment portion (150L), and further into a region underlying the transverse panel (154) preventing the mort from escaping if it becomes positively buoyant. The entrapment portion optionally includes a converging channel into a valved port, to permit extraction of morts. The mortality trap may be located on the distal end of the spar buoy, or at an intermediate location on the lower portion of the spar buoy.