Abstract: A propeller blade having a blade body including a blade base, a blade tip, a pressure side surface, and, a suction side surface. Each of the pressure side surface and the suction side surface extend between the blade base to the blade tip. An end plate is provided on the blade body. The end plate is exposed to an airflow and positioned at the blade base. The end plate projects outwardly of at least a portion of one of the pressure side surface and the suction side surface.

Abstract: A propeller blade having a blade body including a blade base, a blade tip, a pressure side surface, and, a suction side surface. Each of the pressure side surface and the suction side surface extend between the blade base to the blade tip. An end plate is provided on the blade body. The end plate is exposed to an airflow and positioned at the blade base. The end plate projects outwardly of at least a portion of one of the pressure side surface and the suction side surface.

Abstract: An apparatus for collecting geophysical information may include a geophysical information station disposed along a seismic communication cable. A bypass circuit responsive to a command signal is in communication with a switching circuit that is operable to route electrical power, commands, data or a combination to bypass the geophysical information station in response to the command signal. An exemplary method for bypassing a geophysical information station in a geophysical information collection system includes sending a command signal to a bypass circuit and activating one or more switching circuits using the bypass circuit to route electrical power, commands, data or a combination to bypass the geophysical information station in response to the command signal.

Abstract: An apparatus for collecting geophysical information may include a geophysical information station disposed along a seismic communication cable. A bypass circuit responsive to a command signal is in communication with a switching circuit that is operable to route electrical power, commands, data or a combination to bypass the geophysical information station in response to the command signal. An exemplary method for bypassing a geophysical information station in a geophysical information collection system includes sending a command signal to a bypass circuit and activating one or more switching circuits using the bypass circuit to route electrical power, commands, data or a combination to bypass the geophysical information station in response to the command signal.

Abstract: An apparatus for collecting geophysical information may include a geophysical information station disposed along a seismic communication cable. A bypass circuit responsive to a command signal is in communication with a switching circuit that is operable to route electrical power, commands, data or a combination to bypass the geophysical information station in response to the command signal. An exemplary method for bypassing a geophysical information station in a geophysical information collection system includes sending a command signal to a bypass circuit and activating one or more switching circuits using the bypass circuit to route electrical power, commands, data or a combination to bypass the geophysical information station in response to the command signal.

Abstract: This disclosure relates to building trades where precise spacing between structural members ensures support via use of a plurality of elongate spacers. The spacers include at least one intermediate transit tacking member and a pair of nail- or screw-receiving apertures on opposing ends of thereof. One of the opposing ends serves as a pivoting end and the opposite end includes one or more relatively shorter member near the aperture formed therein. These member(s) can be driven into an adjacent trust or other support member while a final precise position is determined. To determine the final precise position to affix a given spacer one or more indicia is provided. Such indicia can include end edges, one or more cut-out features and/or one or more cut-out features and/or numbered or lettered (or other symbols) indicating the relative spacing from one end of the elongate spacer to the other.

Abstract: An apparatus for collecting geophysical information may include a geophysical information station disposed along a seismic communication cable. A bypass circuit responsive to a command signal is in communication with a switching circuit that is operable to route electrical power, commands, data or a combination to bypass the geophysical information station in response to the command signal. An exemplary method for bypassing a geophysical information station in a geophysical information collection system includes sending a command signal to a bypass circuit and activating one or more switching circuits using the bypass circuit to route electrical power, commands, data or a combination to bypass the geophysical information station in response to the command signal.

Abstract: Provided is a permanent seafloor seismic recording system utilizing Micro Electro-Mechanical Systems seismic sensors. The system includes and expandable backbone, multiple hubs and sensor lines. The sensor lines include multiple sensor modules that include 3-C accelerometers and a hydrophone for providing a 4-C sensor module output signal.

Abstract: Provided is a permanent seafloor seismic recording system utilizing Micro Electro-Mechanical Systems seismic sensors. The system includes and expandable backbone, multiple hubs and sensor lines. The sensor lines include multiple sensor modules that include 3-C accelerometers and a hydrophone for providing a 4-C sensor module output signal.

Abstract: A two-conductor bidirectional digital telemetry interface between a seismic sensor acquisition/conversion module and a seismic data collection module. The data collection module is configured as a master electronics device and the sensor acquisition/conversion module is configured as a slave electronics device in the telemetry system. The master device provides power to the slave device over the two conductors. The master device transmits portions of commands to the slave device at a first time and the slave device transmits portions of a digital seismic data packet to the master at a different second time in a fixed-duration frame. The frames are transmitted at regular intervals. The outbound commands and inbound data are encoded by block codes. A phase-locked loop in the slave is locked to a master clock in the master by deriving a clock and a sync point from the block-coded commands it receives from the master.

Abstract: A two-conductor bidirectional digital telemetry interface between a seismic sensor acquisition/conversion module and a seismic data collection module. The data collection module is configured as a master electronics device and the sensor acquisition/conversion module is configured as a slave electronics device in the telemetry system. The master device provides power to the slave device over the two conductors. The master device transmits portions of commands to the slave device at a first time and the slave device transmits portions of a digital seismic data packet to the master at a different second time in a fixed-duration frame. The frames are transmitted at regular intervals. The outbound commands and inbound data are encoded by block codes. A phase-locked loop in the slave is locked to a master clock in the master by deriving a clock and a sync point from the block-coded commands it receives from the master.

Abstract: An instrument for linearizing a non-linear analog output produced from a sensor such as a thermocouple to obtain a true measurement of the parameter or engineering units of interests. The full range of the non-linear analog output is divided into segments and within each segment the second slope or the rate of change of the first slope of the analog output is predetermined and stored. In carrying out measurements, the magnitude of the analog output sensed is converted to constant frequency pulses. When measurements are carried out, within a given segment the corresponding second slope data is employed to modify the frequency of the constant frequency pulses to obtain output pulses for accumulation. These output pulses have a frequency which at any given moment is representative of the first slope of the analog output and which changes at a rate representative of the rate of change of the first slope of the analog output.