Abstract: In one embodiment, a cable extension mechanism includes a housing and a plurality of cable tray segments adapted to retain elongate material therein, wherein each cable tray segment includes first and second cable trays. A sheave is disposed on an axle between the first and second cable trays thereby forming an extendable elbow. At least one wheel assembly is coupled to each cable tray segment to enable the tray segment to articulate between a first position wherein the elongate material is stored and has a first length shorter than an actual length of the elongate material and a substantially flat second position, thereby extending a length of the elongate material disposed thereon.

Abstract: In one embodiment, a cable extension mechanism includes a housing and a plurality of cable tray segments adapted to retain elongate material therein, wherein each cable tray segment includes first and second cable trays. A sheave is disposed on an axle between the first and second cable trays thereby forming an extendable elbow. At least one wheel assembly is coupled to each cable tray segment to enable the tray segment articulate between a first position wherein the elongate material is stored and has a first length shorter than an actual length of the elongate material and a substantially flat second position, thereby extending a length of the elongate material disposed thereon.

Abstract: A non-volatile memory cell and associated programming methods that allow for integration of non-volatile memory with other CMOS integrated circuitry utilizing standard CMOS processing. The non-volatile memory cell includes an antifuse element having a programming node and a capacitor element coupled to the antifuse element and configured to provide one or more voltage pulses to the programming node. The antifuse element is configured to have a changed resistivity after the programming node is subjected to the one or more voltage pulses, the change in resistivity representing a change in logic state. The antifuse element comprises a MOS transistor, its gate being coupled to one of the programming node and a control node, and its source and drain being coupled to the other one of the programming node and the control node. The MOS transistor is formed in a well and the source, drain and well are coupled to the same voltage level.

Abstract: A non-volatile memory cell including an antifuse element having a programming node and a control node, a capacitor element, a precharge element, an access element, and a leakage element. The antifuse element is configured to have changed resistivity (representing a change in logic state) after the programming node is subjected to one or more voltage pulses. The capacitor element, coupled to the programming node, is configured to provide the one or more voltage pulses to the programming node. The precharge element, coupled to the programming node, is configured to increase the one or more voltage pulses provided to the programming to node. The access element, coupled to the control node, is configured to allow determination of the logic state of the antifuse element based on current flow through the access element. The leakage element is coupled to the control node and configured to modify the current flowing through the access element when the resistivity of the antifuse element has not been changed.

Abstract: A high power, high speed gearbox including a compound face gear planetary gear assembly (FGPGA) is provided. The FGPGA includes a first planetary gear set (PGS1) and a second planetary gear set (PGS2). The PGS1 includes a spur gear connected to an input shaft, a plurality of intermediate pinion gears, a first face gear and a second face gear oriented in a planetary arrangement. The PGS2 includes a plurality of gears oriented in a planetary arrangement and operate to turn an output shaft. The PGS1 first and second face gears are configured to engage the spur gear such that the input shaft can have angle of other than 90° with respect to the output shaft. By implementing the PGS1 face gears in a planetary arrangement with the spur gear and the intermediate pinion gears, the rotational direction of the output shaft can be altered by changing a tooth differential between the PGS1 first and second face gears without employing an idler gear in the PGS1.

Abstract: A support structure for piezoelectric elements in a marine seismic cable is provided. The support structure comprises upper and lower cylindrical halves, each with channels formed therein. Two axial channels are adapted to retain three piezoelectric elements each. A third axial channel, positioned between the sensor element channels, is adapted to retain a flexible circuit. Transverse channels between the sensor element channels and the circuit channels accommodate extension from the flexible circuit. The piezoelectric elements are mounted within their respective channels with a resilient pad with adhesive on both sides. The piezoelectric elements are graded so that any group of three piezoelectric elements exhibits approximately the same sensitivity as any of the other three groups of piezoelectric elements on the support structure.

Abstract: A support structure for piezoelectric elements in a marine seismic cable is provided. The support structure comprises upper and lower cylindrical halves, each with channels formed therein. Two axial channels are adapted to retain three piezoelectric elements each. A third axial channel, positioned between the sensor element channels, is adapted to retain a flexible circuit. Transverse channels between the sensor element channels and the circuit channels accommodate extension from the flexible circuit. The piezoelectric elements are mounted within their respective channels with a resilient pad with adhesive on both sides. The piezoelectric elements are graded so that any group of three piezoelectric elements exhibits approximately the same sensitivity as any of the other three groups of piezoelectric elements on the support structure.

Abstract: A hydrophone streamer including a central member running substantially the length of the streamer with a strength member and a plurality of conductors has formed therein space adapted to receive a plurality of a spaced apart pairs of collars, a cylindrical chamber wall between each of the pairs of collars defining a chamber, and one or more hydrophones within the chamber. The chamber wall has one or more opening through it for the free passage of sea water into the chamber, thereby shielding the hydrophones from extraneous noise while exposing the hydrophones to a seismic signal conducted by the sea water surrounding the streamer.

Abstract: An arcuate or flat ferroelectric sensor is incorporated in a seismic streamer. The structure comprises two half-cylinders which are mounted together around a cable. The half-cylinders are coupled together by bolts or pins or any other appropriate means. Each half-cylinder defines a well into which a sensor is mounted. With the sensor in place, the structure is covered over with a sound-transparent material to receive an acoustic signal into the sensor. Electrical leads from the sensor are directed through ports in the half-cylinders, and the leads are connected together to provide a composite sensed signal to the cable in analog form. The sensor in each half-cylinder is a single element hydrophone that, when connected to a sensor in a complementary half cylinder in series or in parallel, forms an acceleration cancelling hydrophone.

Abstract: An arcuate or flat ferroelectric sensor is incorporated in a seismic streamer. The structure comprises an interior cable, a surrounding woven strength member, an overlying foam floatation layer, and an enclosing jacket. One or more elongate channels are formed in the overlying floatation layer, and one or more hydrophones are mounted in the channel(s). The elongate channel enlarges the acoustic aperture for the reception of seismic signals.

Abstract: A hydrophone structure comprises a hydrophone casing within which is mounted a conductive substrate. Sound pressure signals are conducted into the interior of the substrate, on which are mounted piezoelectric crystals on the exterior of the substrate. The volume between the casing and the substrate is nearly filled with a fluid, preferably oil. One or more bubbles of air remain in the volume between the casing and the substrate to permit vibration of the substrate and consequently the piezoelectric hydrophone element.