Abstract: A downhole device is provided that is intended to be co-located with an optical fiber cable to be found, for example by being fixed together in the same clamp. The device has an accelerometer or other suitable orientation determining means that is able to determine its positional orientation, with respect to gravity. A vibrator or other sounder is provided, that outputs the positional orientation information as a suitable encoded and modulated acoustic signal. A fiber optic distributed acoustic sensor deployed in the vicinity of the downhole device detects the acoustic signal and transmits it back to the surface, where it is demodulated and decoded to obtain the positional orientation information. Given that the device is co-located with the optical fiber the position of the fiber can then be inferred. As explained above, detecting the fiber position is important during perforation operations, so that the fiber is not inadvertently damaged.

Abstract: A downhole device is provided that is intended to be co-located with an optical fiber cable to be found, for example by being fixed together in the same clamp. The device has an accelerometer or other suitable orientation determining means that is able to determine its positional orientation, with respect to gravity. A vibrator or other sounder is provided, that outputs the positional orientation information as a suitable encoded and modulated acoustic signal. A fiber optic distributed acoustic sensor deployed in the vicinity of the downhole device detects the acoustic signal and transmits it back to the surface, where it is demodulated and decoded to obtain the positional orientation information. Given that the device is co-located with the optical fiber the position of the fiber can then be inferred. As explained above, detecting the fiber position is important during perforation operations, so that the fiber is not inadvertently damaged.

Abstract: The high sensitivity provided by an enhanced DAS system comprising a DAS interrogator and a high reflectivity fiber allows for the deployment of such a high reflectivity fiber as part of a wireline intervention cable which can be temporarily lowered into a well, thus avoiding the need to permanently cement such a high reflectivity optical fiber cable into the well. Instead, such a wireline cable incorporating the high reflectivity optical fiber has been found to be sensitive enough to detect micro-seismic activity and low frequency strain with many more measurement points and channels than conventional wireline deployed geophones and tiltmeters. Additionally, the cable requires no clamping and can be easily and quickly removed from one well and placed in another well.

Abstract: The high sensitivity provided by an enhanced DAS system comprising a DAS interrogator and a high reflectivity fiber allows for the deployment of such a high reflectivity fiber as part of a wireline intervention cable which can be temporarily lowered into a well, thus avoiding the need to permanently cement such a high reflectivity optical fiber cable into the well. Instead, such a wireline cable incorporating the high reflectivity optical fiber has been found to be sensitive enough to detect micro-seismic activity and low frequency strain with many more measurement points and channels than conventional wireline deployed geophones and tiltmeters. Additionally, the cable requires no clamping and can be easily and quickly removed from one well and placed in another well.

Abstract: A downhole device is provided that is intended to be co-located with an optical fiber cable to be found, for example by being fixed together in the same clamp. The device has an accelerometer or other suitable orientation determining means that is able to determine its positional orientation, with respect to gravity. A vibrator or other sounder is provided, that outputs the positional orientation information as a suitable encoded and modulated acoustic signal. A fiber optic distributed acoustic sensor deployed in the vicinity of the downhole device detects the acoustic signal and transmits it back to the surface, where it is demodulated and decoded to obtain the positional orientation information. Given that the device is co-located with the optical fiber the position of the fiber can then be inferred. As explained above, detecting the fiber position is important during perforation operations, so that the fiber is not inadvertently damaged.

Abstract: A downhole device is provided that is intended to be co-located with an optical fiber cable to be found, for example by being fixed together in the same clamp. The device has an accelerometer or other suitable orientation determining means that is able to determine its positional orientation, with respect to gravity. A vibrator or other sounder is provided, that outputs the positional orientation information as a suitable encoded and modulated acoustic signal. A fiber optic distributed acoustic sensor deployed in the vicinity of the downhole device detects the acoustic signal and transmits it back to the surface, where it is demodulated and decoded to obtain the positional orientation information. Given that the device is co-located with the optical fiber the position of the fiber can then be inferred. As explained above, detecting the fiber position is important during perforation operations, so that the fiber is not inadvertently damaged.

Abstract: One embodiment relates to an, article and a method for producing an article including a plurality of substrates, and an adhesive bonded between at least two of the plurality of substrates. The adhesive can include a polycarbonate copolymer that includes reacted resorcinol, siloxane, and bisphenol-A. Another embodiment relates to an article having a first polyimide substrate, a second polyimide substrate, and an adhesive bonded between the first substrate and the second substrate. The article can have a 2 minute integrated heat release rate of less than or equal to 65 kilowatt-minutes per square meter (kW?min/m2) and a peak heat release rate of less than 65 kilowatts per square meter (kW/m2) as measured using the method of FAR F25.4, in accordance with Federal Aviation Regulation FAR 25.853(d).

Abstract: A downhole device is provided that is intended to be co-located with an optical fiber cable to be found, for example by being fixed together in the same clamp. The device has an accelerometer or other suitable orientation determining means that is able to determine its positional orientation, with respect to gravity. A vibrator or other sounder is provided, that outputs the positional orientation information as a suitable encoded and modulated acoustic signal. A fiber optic distributed acoustic sensor deployed in the vicinity of the downhole device detects the acoustic signal and transmits it back to the surface, where it is demodulated and decoded to obtain the positional orientation information. Given that the device is co-located with the optical fiber the position of the fiber can then be inferred. As explained above, detecting the fiber position is important during perforation operations, so that the fiber is not inadvertently damaged.

Abstract: A composition for the manufacture of a porous, compressible article, the composition comprising a combination of: a plurality of reinforcing fibers; a plurality of polyimide fibers; and a plurality of polymeric binder fibers; wherein the polymeric binder fibers have a melting point lower than the polyimide fibers; methods for forming the porous, compressible article; and articles containing the porous, compressible article. An article comprising a thermoformed dual matrix composite is also disclosed, wherein the composite exhibits a time to peak release, as measured by FAR 25.853 (OSU test), a 2 minute total heat release, as measured by FAR 25.853 (OSU test), and an NBS optical smoke density of less than 200 at 4 minutes, determined in accordance with ASTM E-662 (FAR/JAR 25.853).

Abstract: One embodiment relates to an, article and a method for producing an article including a plurality of substrates, and an adhesive bonded between at least two of the plurality of substrates. The adhesive can include a polycarbonate copolymer that includes reacted resorcinol, siloxane, and bisphenol-A. Another embodiment relates to an article having a first polyimide substrate, a second polyimide substrate, and an adhesive bonded between the first substrate and the second substrate. The article can have a 2 minute integrated heat release rate of less than or equal to 65 kilowatt?minutes per square meter (kW?min/m2) and a peak heat release rate of less than 65 kilowatts per square meter (kW/m2) as measured using the method of FAR F25.4, in accordance with Federal Aviation Regulation FAR 25.853(d).

Abstract: One embodiment relates to an article and a method for producing an article including a plurality of substrates, and an adhesive bonded between at least two of the plurality of substrates. The adhesive can include a polycarbonate copolymer that includes reacted resorcinol, siloxane, and bisphenol-A. Another embodiment relates to an article having a first polyimide substrate, a second polyimide substrate, and an adhesive bonded between the first substrate and the second substrate. The article can have a 2 minute integrated heat release rate of less than or equal to 65 kilowatt-minutes per square meter (kW-min/m2) and a peak heat release rate of less than 65 kilowatts per square meter (kW/m2) as measured using the method of FAR F25.4, in accordance with Federal Aviation Regulation FAR 25.853(d).

Abstract: A composition for the manufacture of a porous, compressible article, the composition comprising a combination of: a plurality of reinforcing fibers; a plurality of polyimide fibers; and a plurality of polymeric binder fibers; wherein the polymeric binder fibers have a melting point lower than the polyimide fibers; methods for forming the porous, compressible article; and articles containing the porous, compressible article. An article comprising a thermoformed dual matrix composite is also disclosed, wherein the composite exhibits a time to peak release, as measured by FAR 25.853 (OSU test), a 2 minute total heat release, as measured by FAR 25.853 (OSU test), and an NBS optical smoke density of less than 200 at 4 minutes, determined in accordance with ASTM E-662 (FAR/JAR 25.853).

Abstract: A dynamic loudspeaker comprises two spaced apart motor units (7,8) each incorporating a centre pole (12) operating in opposite phase resulting in cancellation of 3rd order non-linearities, and the two motors (7,8) being linked together by a member (6) connecting both centre poles (12) of each motor unit (7,8).