Abstract: A method includes deploying a plurality of seismic sensors onto the bottom of a body of water. The deploying includes moving at least one sensor frame having seismic sensors disposed therein in fixed positions to the bottom. A vessel is moved on a surface of the body of water proximate a location of the seismic sensors on the bottom. The vessel has mounted thereon a plurality of seismic sources at fixed positions in a direction transverse to a direction of motion of the e vessel. The sources are suspended from the vessel in the water. At selected times, the sources are actuated. Seismic energy is detected at the plurality of seismic sensors in response to energy emitted by the sources interacting with formations below the bottom of the body of water.

Abstract: An ignition and combustion assist system and method comprising a plasma igniter and electronic driver unit for use with gas turbine engines operating under low air densities, reduced voltage conditions and overall pressure ratios of 3:1 to 7:1. The plasma igniter has an inner chamber housing a centrally positioned and electrically isolated electrode attached to an electrical lead, driver unit, and AC or DC power supply. The electrode features a corner positioned near an outlet end of the igniter, where a plasma arc ignites a fuel-air mixture creating a flame extending into a primary burn region of a combustor of the gas turbine. The driver unit is in two embodiments and configured with low-cost microsecond voltage wave time periods or energy-efficient nano-second pulses. The method uses the plasma igniter and the electronic driver units described herein separately with other components or together.

Abstract: An ignition and combustion assist system and method comprising a plasma igniter and electronic driver unit for use with gas turbine engines operating under low air densities, reduced voltage conditions and overall pressure ratios of 3:1 to 7:1. The plasma igniter has an inner chamber housing a centrally positioned and electrically isolated electrode attached to an electrical lead, driver unit, and AC or DC power supply. The electrode features a corner positioned near an outlet end of the igniter, where a plasma arc ignites a fuel-air mixture creating a flame extending into a primary burn region of a combustor of the gas turbine. The driver unit is in two embodiments and configured with low-cost microsecond voltage wave time periods or energy-efficient nano-second pulses. The method uses the plasma igniter and the electronic driver units described herein separately with other components or together.

Abstract: An ignition and combustion assist system and method comprising a plasma igniter and electronic driver unit for use with gas turbine engines operating under low air densities, reduced voltage conditions and overall pressure ratios of 3:1 to 7:1. The plasma igniter has an inner chamber housing a centrally positioned and electrically isolated electrode attached to an electrical lead, driver unit, and AC or DC power supply. The electrode features a corner positioned near an outlet end of the igniter, where a plasma arc ignites a fuel-air mixture creating a flame extending into a primary burn region of a combustor of the gas turbine. The driver unit is in two embodiments and configured with low-cost microsecond voltage wave time periods or energy-efficient nano-second pulses. The method uses the plasma igniter and the electronic driver units described herein separately with other components or together.

Abstract: An ignition and combustion assist system and method comprising a plasma igniter and electronic driver unit for use with gas turbine engines operating under low air densities, reduced voltage conditions and overall pressure ratios of 3:1 to 7:1. The plasma igniter has an inner chamber housing a centrally positioned and electrically isolated electrode attached to an electrical lead, driver unit, and AC or DC power supply. The electrode features a corner positioned near an outlet end of the igniter, where a plasma arc ignites a fuel-air mixture creating a flame extending into a primary burn region of a combustor of the gas turbine. The driver unit is in two embodiments and configured with low-cost microsecond voltage wave time periods or energy-efficient nano-second pulses. The method uses the plasma igniter and the electronic driver units described herein separately with other components or together.

Abstract: An ignition and combustion assist system and method comprising a plasma igniter and electronic driver unit for use with gas turbine engines operating under low air densities, reduced voltage conditions and overall pressure ratios of 3:1 to 7:1. The plasma igniter has an inner chamber housing a centrally positioned and electrically isolated electrode attached to an electrical lead, driver unit, and AC or DC power supply. The electrode features a corner positioned near an outlet end of the igniter, where a plasma arc ignites a fuel-air mixture creating a flame extending into a primary burn region of a combustor of the gas turbine. The driver unit is in two embodiments and configured with low-cost microsecond voltage wave time periods or energy-efficient nano-second pulses. The method uses the plasma igniter and the electronic driver units described herein separately with other components or together.

Abstract: A method for seismic surveying includes deploying a first seismic energy source at a plurality of locations along a source line. Locations are determined by, (i) setting a shot point at one end of the line, setting a minimum distance between shot points and setting a nominal shot point interval being greater than a Nyquist maximum spacing at a maximum spatial frequency to be evaluated in the subsurface area, (ii) calculating a maximum distance between shot points as a difference between twice the nominal shot point interval and the minimum distance, (iii) dividing a span between the maximum distance and the minimum distance into equally spaced samples, and choosing at random one of the equally spaced samples to calculate a shot point subsequent to the initial shot point; and (iv) setting the calculated shot point as the initial shot point and repeating (ii) and (iii) until the subsequent calculated shot point is within a predetermined distance of an opposed end of the first source line.

Abstract: An ignition and combustion assist system and method comprising a plasma igniter and electronic driver unit for use with gas turbine engines operating under low air densities, reduced voltage conditions and overall pressure ratios of 3:1 to 7:1. The plasma igniter has an inner chamber housing a centrally positioned and electrically isolated electrode attached to an electrical lead, driver unit, and AC or DC power supply. The electrode features a corner positioned near an outlet end of the igniter, where a plasma arc ignites a fuel-air mixture creating a flame extending into a primary burn region of a combustor of the gas turbine. The driver unit is in two embodiments and configured with low-cost microsecond voltage wave time periods or energy-efficient nano-second pulses. The method uses the plasma igniter and the electronic driver units described herein separately with other components or together.

Abstract: A turbine blade tip includes a tip cap disposed over a blade airfoil and having a pressure side edge and a suction side edge. A notch is formed by a radially inward step adjacent to the suction side edge of the tip cap. The notch is defined by a radially extending step wall and a radially outward facing land. The step wall extends radially inward from the suction side edge of the tip cap to the land, whereby the land is positioned radially inward in relation to a radially outer surface of the tip cap. The notch extends along at least a portion of the suction sidewall in a direction from the leading edge to the trailing edge. In a further aspect, a method is provided for servicing a blade that includes machining a suction side notch as described above.

Abstract: A turbine blade includes a tip cap disposed over an outer wall of a blade airfoil. A trench is defined on a radially outer side of the tip cap facing a hot gas path fluid. The trench is formed by a trench floor flanked on laterally opposite sides by first and second trench side faces such that the trench floor is located radially inwardly in relation to a radially outer surface of the tip cap. The trench extends from a trench inlet located at or proximal to an airfoil leading edge to a trench outlet located at or proximal to an airfoil trailing edge. The trench is configured to entrain a tip leakage flow from the trench inlet to the trench outlet.

Abstract: A turbine blade includes a tip cap disposed over an outer wall of a blade airfoil. A trench is defined on a radially outer side of the tip cap facing a hot gas path fluid. The trench is formed by a trench floor flanked on laterally opposite sides by first and second trench side faces such that the trench floor is located radially inwardly in relation to a radially outer surface of the tip cap. The trench extends from a trench inlet located at or proximal to an airfoil leading edge to a trench outlet located at or proximal to an airfoil trailing edge. The trench is configured to entrain a tip leakage flow from the trench inlet to the trench outlet.

Abstract: A turbine blade tip includes a tip cap disposed over a blade airfoil and having a pressure side edge and a suction side edge. A notch is formed by a radially inward step adjacent to the suction side edge of the tip cap. The notch is defined by a radially extending step wall and a radially outward facing land. The step wall extends radially inward from the suction side edge of the tip cap to the land, whereby the land is positioned radially inward in relation to a radially outer surface of the tip cap. The notch extends along at least a portion of the suction sidewall in a direction from the leading edge to the trailing edge. In a further aspect, a method is provided for servicing a blade that includes machining a suction side notch as described above.

Abstract: A method for seismic surveying includes deploying a group of vertically sensitive seismic particle motion responsive sensors at each of a plurality of geodetic survey positions. The groups each include at least two sensors spaced apart by a first selected horizontal distance. The groups are separated from each other by a second selected distance larger than the first distance. Signals detected by each of the sensors resulting from actuation of a seismic energy source are recorded. At least one of an in-line and a cross-line component of a gradient of the vertical component of the seismic wavefield is determined at each group location by determining a difference between the signals detected by each sensor in a respective group.

Abstract: Secure transfer of electronic files containing confidential information is achieved by selecting and copying files to be transferred to an intended recipient and, prior to transfer, subjecting the copies to consolidation, compression, chunking and encryption. Decryption, unchunking and decompression of the transferred files can only be performed by a recipient who has also received a verification code, an encrypted and password protected sector file, and an encrypted password file. Decryption of the password file requires a private certificate available only to the intended recipient. Decryption of the other files requires a one-time random transaction password contained in the password file.

Abstract: A method for seismic surveying includes deploying a group of vertically sensitive seismic particle motion responsive sensors at each of a plurality of geodetic survey positions. The groups each include at least two sensors spaced apart by a first selected horizontal distance. The groups are separated from each other by a second selected distance larger than the first distance. Signals detected by each of the sensors resulting from actuation of a seismic energy source are recorded. At least one of an in-line and a cross-line component of a gradient of the vertical component of the seismic wavefield is determined at each group location by determining a difference between the signals detected by each sensor in a respective group.

Abstract: A watertight door system that provides for subdivision of cargo holds, and having a door frame assembly with a sliding door. Conveyor support stringers are movably connected to the sliding door and conveyor idlers are movably connected to and the conveyor support stringers. A linear actuator associated with the door frame assembly selectively actuates the door between an open and closed position, whereby actuation of the door by the hydraulic cylinder causes the conveyor support stringers to move with the door, and the conveyor idlers to be lowered without removal thereof. Belt side plugs are positioned on either side of the door frame assembly, and can move both inwardly against a conveyor belt edge and outwardly from the conveyor belt edge.

Abstract: Digital image storage and management systems capable of producing encrypted DICOM volumes on different types of media (e.g., Blu-ray, CD, DVD, memory stick, USB flash drive, etc.), with or without the automatic generation of labels, systems and mechanisms to generate and manage passwords for the encrypted volumes, and systems and mechanisms to manage access to encrypted data on such volumes are disclosed. Generated encrypted DICOM volumes, which can comprise confidential patient data, can be securely interchanged, archived, and distributed to users. The disclosed systems and methods can permit authorized users to access encrypted data, even if the users do not have access to the original encryption mechanism. Encrypted data stored on the volume can be easily and securely accessed by a variety of authorized users.

Abstract: A watertight door system that provides for subdivision of cargo holds, and having a door frame assembly with a sliding door. Conveyor support stringers are movably connected to the sliding door and conveyor idlers are movably connected to and the conveyor support stringers. A linear actuator associated with the door frame assembly selectively actuates the door between an open and closed position, whereby actuation of the door by the hydraulic cylinder causes the conveyor support stringers to move with the door, and the conveyor idlers to be lowered without removal thereof. Belt side plugs are positioned on either side of the door frame assembly, and can move both inwardly against a conveyor belt edge and outwardly from the conveyor belt edge.

Abstract: A method for marine seismic surveying includes towing seismic sensors in a plurality of streamers in the water, actuating a seismic energy source in the water at selected times and detecting seismic signals at the sensors resulting from the actuation of the source. A data trace is created for each of the detected signals. At least one Fresnel zone is determined for at least some of the seismic data traces. A contribution of each of the traces to each one of a plurality of bins defined in a predetermined pattern is computed, based on the Fresnel zone associated with each trace. Based on the computed contributions, a maximum lateral distance between corresponding seismic sensors is determined that will result in a contribution sum above a selected threshold.

Abstract: Digital image storage and management systems capable of producing encrypted DICOM volumes on different types of media (e.g., Blu-ray, CD, DVD, memory stick, USB flash drive, etc.), with or without the automatic generation of labels, systems and mechanisms to generate and manage passwords for the encrypted volumes, and systems and mechanisms to manage access to encrypted data on such volumes are disclosed. Generated encrypted DICOM volumes, which can comprise confidential patient data, can be securely interchanged, archived, and distributed to users. The disclosed systems and methods can permit authorized users to access encrypted data, even if the users do not have access to the original encryption mechanism. Encrypted data stored on the volume can be easily and securely accessed by a variety of authorized users.