Abstract: A fluid turbine may include a vertically-orientable shaft having at least one opening extending transversely therethrough, a first blade portion configured for vertical orientation on first side of the shaft, a second blade portion configured for vertical orientation on a second opposite side of the shaft, at least one rod extending through the shaft opening and connectable at a first end to the first blade portion and at a second end to the second blade portion. A reinforcing sleeve may extend through the shaft opening and may be interposed between the rod and the shaft opening for reinforcing at least one of the shaft, the at least one shaft opening, or the rod against forces exerted by the first and second blade portions when fluid impacts the first and second blade portions.

Abstract: Systems, methods, and computer program products are disclosed for controlling a voltage output of a turbine. Controlling a voltage output of a turbine includes a rectifier for converting an AC output of a turbine to a DC voltage; a sensor for measuring the DC voltage; a charge controller for receiving the DC voltage from the rectifier and produce a DC output, including: a first circuit meeting a first performance criterion for a first DC range, a second circuit meeting a second performance criterion for a second DC operating range, a switch channeling the DC voltage between the first and second circuits; and a processor for receiving the DC voltage measurement from the sensor, and use the switch to channel the DC voltage between the first and second circuits, thereby meeting the first and second performance criteria when the DC voltage is in the first and second DC ranges, respectively.

Abstract: Systems, methods, and non-transitory computer readable media including instructions for coordinating MPPT operations for a cluster of geographically-associated fluid turbines are disclosed. Coordinating MPPT operations for a cluster of geographically-associated fluid turbines includes receiving data from the cluster of geographically-associated fluid turbines; determining changes to total power output of the cluster based on changes in loading states of individual fluid turbines in the cluster; selecting a combination of loading states for the individual fluid turbines in the cluster to coordinate total power output for the cluster; and transmitting the selected combination of loading states to at least some of the individual fluid turbines in the cluster in order to vary rotational speeds of the at least some of the individual fluid turbines in the cluster.

Abstract: Systems, methods, and non-transitory computer readable media including instructions for synchronizing a plurality of geographically-associated fluid turbines.

Abstract: Methods, processing systems, and computer-readable mediums for automated designing of patient-specific cranial implants may include extracting pixel data from a DICOM file; generating a virtual skull model based on the pixel data; identifying a mid-sagittal plane of the virtual skull model; identifying a surgical hole in the virtual skull model; mirroring a reference side of the virtual skull model onto a surgical hole side of the virtual skull model; subtracting the surgical hole side from the mirrored reference side to generate a virtual cranial implant; and generating a virtual two-part mold based on the virtual cranial implant. A physical two-part mold can be 3D printed based on the virtual two-part mold, and a physical cranial implant can be constructed using the physical two-part mold.

Abstract: A replicated block storage service provides durable and high performance network-attached storage replicated in two or more zones of a single region, and remains available despite a single zone failure. A probe file is generated to determine a health state of a replicated disk. When a disk is degraded, a lease is created indicating which replica is trusted and providing visibility to backend jobs to facilitate reconciliation of data between the first replica and the second replica. Moreover, degraded file markers are generated for use by the backend jobs in quickly identifying the data to be copied.

Abstract: Systems, methods, and non-transitory computer readable media including instructions for a dual-channel fluid turbine controller. A dual-channel fluid turbine controller includes at least one processor configured to: receive, via an AC channel coupled to an AC output of a fluid turbine, first signals indicating fluctuations in power generated by the fluid turbine operating beneath a grid power supply threshold; access an MPPT protocol; determine a correspondence between the first signals and a portion of the MPPT protocol; apply the portion of the MPPT protocol to a generator of the fluid turbine to generate greater power than would be generated in an absence of the MPPT protocol, wherein the generated power is stored as energy in a capacitor associated with the generator; receive, via a DC channel, second signals indicating a level of energy stored in the capacitor; and use the second signals to determine when to release the stored energy.

Abstract: An electric roofing torch comprising a tubular body having an upstream end and a downstream end, a fan unit mounted in the tubular body to drive a flow of air through the tubular body and a heater tube comprising a heater matrix, the heater tube being mounted in the tubular body to heat the flow of air as it passes through the tubular body. The fan unit comprises an electric vaneaxial fan which is mounted upstream of the heater tube. The fan unit is mounted in the tubular body to drive a flow of air through the tubular body at velocity, pressure and volume that is sufficient for roofing operations such as laying roofing membranes, with zero carbon emissions. There is also provided a method of providing a working flow of hot air from the electric roofing torch for such a roofing operation.

Abstract: Systems, methods, and non-transitory computer readable media including instructions for an aggregated voltage controller for a cluster of fluid turbines. An aggregated voltage controller includes at least one processor configured to: receive a target voltage for the cluster; receive via a plurality of rectifiers, each associated with a different turbine, an indication of a DC voltage associated with each turbine, wherein the DC voltage associated with at least one of the turbines is below the target voltage; and based on the received indications of the DC voltage signals associated with each turbine in the cluster, output a control signal to each of a plurality of DC-DC converters associated with the plurality of rectifiers, each control signal configured to regulate each DC-DC converter to produce a DC output at the target voltage such that combining each DC output in parallel produces an aggregated DC voltage conforming to the target voltage.

Abstract: Systems, methods, and non-transitory computer readable media including instructions for a dual-channel fluid turbine controller. A dual-channel fluid turbine controller includes at least one processor configured to: receive, via an AC channel coupled to an AC output of a fluid turbine, first signals indicating fluctuations in power generated by the fluid turbine operating beneath a grid power supply threshold; access an MPPT protocol; determine a correspondence between the first signals and a portion of the MPPT protocol; apply the portion of the MPPT protocol to a generator of the fluid turbine to generate greater power than would be generated in an absence of the MPPT protocol, wherein the generated power is stored as energy in a capacitor associated with the generator; receive, via a DC channel, second signals indicating a level of energy stored in the capacitor; and use the second signals to determine when to release the stored energy.

Abstract: This disclosure describes many innovations including but not limited to systems, methods, and non-transitory computer readable media containing instructions for controlling an energy generator.

Abstract: Systems, methods, and non-transitory computer readable media including instructions for an inverter for communicating power from a cluster of fluid turbines to an electrical grid. An inverter for communicating power from a cluster of turbines to a grid includes circuitry configured to receive via a rectifier associated with each turbine in the cluster, a DC voltage such that a plurality of DC voltages from differing turbines are received and aggregated; at least one processor configured to: confirm that a connection to the grid conforms with at least one operating parameter; when conformity of the grid connection with the operating parameter is confirmed, enable inversion of the aggregated DC voltage to an AC voltage compatible with the grid and enable output of the AC voltage to the grid; and when conformity of the grid connection with the operating parameter is not confirmed, prevent output of the AC voltage to the grid.

Abstract: Systems, methods, and non-transitory computer readable media including instructions for coordinating MPPT operations for a cluster of geographically-associated fluid turbines are disclosed. Coordinating MPPT operations for a cluster of geographically-associated fluid turbines includes receiving data from the cluster of geographically-associated fluid turbines; determining changes to total power output of the cluster based on changes in loading states of individual fluid turbines in the cluster; selecting a combination of loading states for the individual fluid turbines in the cluster to coordinate total power output for the cluster; and transmitting the selected combination of loading states to at least some of the individual fluid turbines in the cluster in order to vary rotational speeds of the at least some of the individual fluid turbines in the cluster.

Abstract: Systems, methods, and non-transitory computer readable media including instructions for synchronizing a plurality of geographically-associated fluid turbines.

Abstract: Systems, methods, and non-transitory computer readable media including instructions for synchronizing a plurality of geographically-associated fluid turbines.

Abstract: A method for synchronous replication of stream data includes receiving a stream of data blocks for storage at a first storage location associated with a first geographical region and at a second storage location associated with a second geographical region. The method also includes synchronously writing the stream of data blocks to the first storage location and to the second storage location. While synchronously writing the stream of data blocks, the method includes determining an unrecoverable failure at the second storage location. The method also includes determining a failure point in the writing of the stream of data blocks that demarcates data blocks that were successfully written and not successfully written to the second storage location. The method also includes synchronously writing, starting at the failure point, the stream of data blocks to the first storage location and to a third storage location associated with a third geographical region.

Abstract: A method for managing data processing includes receiving, from a user of a data query system, a data query for data stored in a data store in communication with the data query system. The method also includes receiving a staleness parameter indicating an upper time boundary for the data query. The upper time boundary limits a query response to data within the data store that is older than the upper time boundary. The method further includes determining whether the data stored within the data store satisfies the staleness parameter. When a portion of the data within the data store fails to satisfy the staleness parameter, the method includes generating the query response that excludes the portion of the data that fails to satisfy the staleness parameter.

Abstract: A method for synchronous replication of stream data includes receiving a stream of data blocks for storage at a first storage location associated with a first geographical region and at a second storage location associated with a second geographical region. The method also includes synchronously writing the stream of data blocks to the first storage location and to the second storage location. While synchronously writing the stream of data blocks, the method includes determining an unrecoverable failure at the second storage location. The method also includes determining a failure point in the writing of the stream of data blocks that demarcates data blocks that were successfully written and not successfully written to the second storage location. The method also includes synchronously writing, starting at the failure point, the stream of data blocks to the first storage location and to a third storage location associated with a third geographical region.

Abstract: A method for managing data processing includes receiving, from a user of a data query system, a data query for data stored in a data store in communication with the data query system. The method also includes receiving a staleness parameter indicating an upper time boundary for the data query. The upper time boundary limits a query response to data within the data store that is older than the upper time boundary. The method further includes determining whether the data stored within the data store satisfies the staleness parameter. When a portion of the data within the data store fails to satisfy the staleness parameter, the method includes generating the query response that excludes the portion of the data that fails to satisfy the staleness parameter.