Abstract: Methods are provided to package and deploy a marine vibrator for use in connection with marine seismic surveys. Marine vibrators are provided with a number of buoyancy configurations with corresponding techniques for controlling the submergence depth of the marine vibrators. An exemplary marine vibrator comprises a positively buoyant hydrodynamic tow body, comprising: a low frequency electro-acoustic projector; a power electronics system; a control-monitoring electronics system; and a pressure compensation system, wherein the hydrodynamic tow body comprises one or more active control surfaces to adjust a submergence depth and a roll attitude of the hydrodynamic tow body. Additional embodiments employ a free-flooding, load-bearing frame with positive or negative buoyancy.

Abstract: Methods are provided to package and deploy a marine vibrator for use in connection with marine seismic surveys. Marine vibrators are provided with a number of buoyancy configurations with corresponding techniques for controlling the submergence depth of the marine vibrators. An exemplary marine vibrator comprises a positively buoyant hydrodynamic tow body, comprising: a low frequency electro-acoustic projector; a power electronics system; a control-monitoring electronics system; and a pressure compensation system, wherein the hydrodynamic tow body comprises one or more active control surfaces to adjust a submergence depth and a roll attitude of the hydrodynamic tow body. Additional embodiments employ a free-flooding, load-bearing frame with positive or negative buoyancy.

Abstract: A coherent sound source is provided for marine seismic surveys. An underwater sound projector for producing time-harmonic waveforms comprises two pistons positioned on either side of an electro-magnetic force generator substantially having mechanical and magnetic symmetry about its geometric center thereby creating a virtual node to substantially cancel reaction loads that occur when the pistons are actuated. The underwater sound projector optionally also includes control systems to improve the fidelity of the force generator, provide pressure compensation to the pistons, finely adjust the static position of the pistons, and change the depth and roll when it is configured as tow body. A plurality of underwater sound projectors can be configured in an array.

Abstract: A coherent sound source is provided for marine seismic surveys. An exemplary underwater sound projector comprises a plurality of pistons actuated by an electromagnetic force generator having components comprising a stator, armatures, electrical coils, and permanent magnets. The pistons and the components are arranged to create mechanical and magnetic symmetry about a geometric center of the projector to reduce reaction loads that occur when the pistons are actuated. The stator and the armatures have magnetic poles that employ a tapered geometry. The projector optionally includes control systems to improve the fidelity of the force generator, provide pressure compensation to the pistons, finely adjust the static position of the pistons, and/or change the depth and roll when the projector is configured as a tow body. A plurality of such projectors can be configured in an array.

Abstract: A coherent sound source is provided for marine seismic surveys. An underwater sound projector for producing time-harmonic waveforms comprises two pistons positioned on either side of an electro-magnetic force generator substantially having mechanical and magnetic symmetry about its geometric center thereby creating a virtual node to substantially cancel reaction loads that occur when the pistons are actuated. The underwater sound projector optionally also includes control systems to improve the fidelity of the force generator, provide pressure compensation to the pistons, finely adjust the static position of the pistons, and change the depth and roll when it is configured as tow body. A plurality of underwater sound projectors can be configured in an array.

Abstract: Low cost miniature vector sensors are provided. An acoustic vector sensor is provided that comprises at least one accelerometer to measure at least one component of acoustic particle acceleration, wherein the at least one accelerometer has a resonant frequency within a measurement band of the acoustic vector sensor. In addition, a method is disclosed for measuring an acoustic signal. The method comprises the steps of configuring an array of acoustic vector sensors comprised of at least one accelerometer to measure at least one component of acoustic particle acceleration; operating the at least one accelerometer at a resonant frequency within a measurement band of the acoustic vector sensor; and generating a voltage using one or more of the acoustic vector sensors representative of the acoustic signal as the acoustic signal propagates past the array. The voltage optionally indicates a bearing of the acoustic signal.

Abstract: A cantilever beam accelerometer design is disclosed that obviates the need of attaching electrical leads directly to the piezoelectric plates. According to one aspect of the invention, two identical proof-masses are positioned on top of each piezoelectric plate in a symmetrical fashion. In advance of attaching the masses to the plates, electrical leads are attached to the masses by some suitable technique such as soldering. Each proof-mass is positioned on its respective piezoelectric plate as close to the free-end of the beam as practical, to keep the size of the mass reasonably small. The disclosed concept is useful for both series and parallel configurations of the piezoelectric plates, wherein the polarization vectors are in opposite directions for two plates connected in series and the polarization vectors are in the same direction for two plates connected in parallel.

Abstract: A dual cantilever beam relaxor-based piezoelectric single crystal accelerometer is provided. A flexural sensing structure is provided that employs at least two piezoelectric cantilever beams having their longitudinal axes disposed in a substantially parallel arrangement with each beam containing at least one relaxor-based single crystal transduction element having its polarization axis substantially perpendicular to the longitudinal axis of the beam. One end is mounted to a rigid base and the other end can be mounted to a seismic proof-mass or can be free, wherein the base is subjected to dynamic excitation from either mechanical or acoustical origin. The flexible sensing structure can optionally be encapsulated in a viscoelastic material having a mechanical compliance and loss that is substantially greater than that of the flexible sensing structure.

Abstract: Low cost miniature vector sensors are provided. An acoustic vector sensor is provided that comprises at least one accelerometer to measure at least one component of acoustic particle acceleration, wherein the at least one accelerometer has a resonant frequency within a measurement band of the acoustic vector sensor. In addition, a method is disclosed for measuring an acoustic signal. The method comprises the steps of configuring an array of acoustic vector sensors comprised of at least one accelerometer to measure at least one component of acoustic particle acceleration; operating the at least one accelerometer at a resonant frequency within a measurement band of the acoustic vector sensor; and generating a voltage using one or more of the acoustic vector sensors representative of the acoustic signal as the acoustic signal propagates past the array. The voltage optionally indicates a bearing of the acoustic signal.

Abstract: A drainage channel installation device comprises a channel-securing member and a channel-hanging member. The channel-securing member releasably engages the channel-hanging member and has opposed ends that are adapted to be releasably secured to the opposed side walls of a drainage channel. The channel-hanging-member has both an engaging end that is adapted to releasably engage the channel-securing member and a suspending end that is adapted to receive and retain a suspending member. As a result, when the channel-securing member and the channel-hanging member are releasably engaged, the channel-securing member is releasably secured to the opposed side walls of the drainage channel and the suspending end of the channel-hanging member receives and retains the suspending member, the drainage channel can be suspended from the suspending member for installation of the drainage channel. The drainage installation device is reusable and allows the drainage channel to be positioned within a trench at any desired level.

Abstract: An interconnect device (e.g., a switch) includes a port operably coupled to a packet broadcaster for routing unicast and/or multicast packets of data in packet-based input/output communications. For an inbound packet, at least two combinations of a source port and one or more destination ports, and one or more destination paths associated with each of said one or more destination ports may be determined by the packet broadcaster in a single lookup of a memory (e.g., a random access memory).

Abstract: The present invention is directed to buffer arrangements (e.g., via concatenation) to support differential link distances at full bandwidth.

Abstract: A port configuration mechanism is provided at a host for multiple port allocation and shared resource utilization to support multiple port configurations for different port operation modes on a host to handle data transfers in a switched fabric data network for scalable solutions.

Abstract: An interconnect device (e.g., a switch) includes a port operably coupled to a packet broadcaster for routing unicast and/or multicast packets of data in packet-based input/output communications. For an inbound packet, at least two combinations of a source port and one or more destination ports, and one or more destination paths associated with each of said one or more destination ports may be determined by the packet broadcaster in a single lookup of a memory (e.g., a random access memory).

Abstract: A method and apparatus for forming a trench drain includes an elongated trench form, first and second spaced apart frame rails, a support member and a first and second fastener. The trench form includes at least one folding member folded along predetermined lines. The support member is affixed to the first and second frame rails to maintain the first and second rails in a fixed position relative to each other. The support member includes first and second fastener bearing surfaces spaced above respective uppermost surfaces of transverse portions of the first and second frame rails. The first and second fastener bear against fastener bearing surfaces of the support member and releasably engage the first and second frame rail. A joint support member may be included to align adjacent trench drain assemblies.

Abstract: A port configuration mechanism is provided at a host for multiple port allocation and shared resource utilization to support multiple port configurations for different port operation modes on a host to handle data transfers in a switched fabric data network for scalable solutions.

Abstract: The present invention is directed to a method and apparatus for forming a trench drain. In one embodiment, the apparatus for forming a trench drain includes an elongated trench form, first and second spaced apart frame rails, a support member and a first and second fastener. The trench form includes at least one folding member folded along predetermined lines. The support member is affixed to the first and second frame rails to maintain the first and second rails in a fixed position relative to each other. The support member includes first and second fastener bearing surfaces spaced above respective uppermost surfaces of transverse portions of the first and second frame rails. The first and second fastener bear against fastener bearing surfaces of the support member and releasably engage the first and second frame rail. A joint support member may be included to align adjacent trench drain assemblies.

Abstract: Acoustic intensity is measured by a submerged probe consisting of two passive geophones mounted in spaced relationship with their sensing axes aligned. The geophones are connected through a cable to a remote spectrum analyzer in which acoustic intensity is computed from the velocity gradient between the two geophones. The exclusive use of geophones, which inherently have low impedance outputs, eliminates the need for preamplification in the probe. The geophones are mounted inside an acoustically transparent, thin rubber shell, which reduces the effects of noise due to flow.

Abstract: A pneumatic-electromagnetic latch is disclosed as applied to bring the sealing jaws of an L-sealer into pressure engagement without impact. An electromagnet mounted on a piston rod of a pneumatic actuator attracts and retains an armature attached to the sealing jaws when the jaws are brought close to the sealing bed. The cylinder of the actuator is attached to the frame and when actuated it draws the sealing jaws into smooth pressure contact with the sealing bed. Upon deenergization of the electromagnet the jaws are released to open for the next sealing cycle and the release of fluid pressure in the actuator extends the piston rod to position for the next operation.