Abstract: A marine seismic streamer comprising a solid, hydrophobic core member that is encased in a hydrophobic streamer skin/casing. The hydrophobic streamer skin may be extruded onto and/or heat welded to the hydrophobic core member. The hydrophobic streamer skin/casing may comprise a thermoplastic polyurethane that includes fluorine and/or silicon moieties, silicon, polydimethylsiloxane or the like. The hydrophobic streamer skin/casing may reduce the drag of the streamer and may provide anti-biofouling properties to the streamer. A hydrophobic paint, coating or polymer may in some instances be disposed on top of the hydrophobic streamer skin/casing.

Abstract: A method for identifying a seismic event includes extracting a portion of a plurality of seismic data signals based on energy levels in the plurality, comparing the extracted portion to a known pattern and determining a correlation, and identifying the seismic event based on the correlation. A computer program product and devices for implementing the method are provided.

Abstract: A method for distributing context-based data using an acoustic receiving device and a high frequency analog acoustic signal is disclosed. The acoustic receiving device a high frequency analog acoustic signal. A high frequency analog acoustic signal is of a frequency of at least 21,000 Hz and contains encoded data. The high frequency analog acoustic signal is converted to a digital acoustic signal and then analyzed to obtain the encoded data. The data is decoded to obtain information, and the information is then displayed on the acoustic receiving device.

Abstract: A beamforming module includes a conversion unit configured to convert an input signal to generate a converted signal using at least one conversion function, a weight calculator configured to calculate a converted signal weight as a weight for the converted signal, and a synthesizer configured to generate a result signal using the converted signal and the converted signal weight.

Abstract: The invention comprises a method for mapping a volume of the Earth's subsurface encompassing a selected path within said volume, comprising dividing the volume of the Earth's subsurface into a three-dimensional grid of voxels and transforming detected seismic signals representing seismic energy originating from said volume of the Earth's subsurface when no induced fracturing activity is occurring along said selected path and conducted to a recording unit for recording into signals representing energy originating from the voxels included in said grid of voxels, and utilizing said transformed seismic signals to estimate spatially continuous flow paths for reservoir fluids through said volume of the Earth's subsurface to said selected path.

Abstract: The present invention relates to an ultrasound transducer device comprising at least one cMUT cell (30) for transmitting and/or receiving ultrasound waves, the cMUT cell (30) comprising a cell membrane (30a) and a cavity (30b) underneath the cell membrane. The device further comprises a substrate (10) having a first side (10a) and a second side (10b), the at least one cMUT cell (30) arranged on the first side (10a) of the substrate (10). The substrate (10) comprises a substrate base layer (12) and a plurality of adjacent trenches (17a) extending into the substrate (10) in a direction orthogonal to the substratesides (10a, 10b), wherein spacers (12a) are each formed between adjacent trenches (17a). The substrate (10) further comprises a connecting cavity (17b) which connects the trenches (17a) and which extends in a direction parallel to the substrate sides (10a, 10b), the trenches (17a) and the connecting cavity (17b) together forming a substrate cavity (17) in the substrate (10).

Abstract: The present disclosure provides a system and method for estimating fracture density within a subsurface formation from S-wave seismic data. In one embodiment, the S-wave seismic data is separated into fast (“S1”) and slow (“S2”) data. A computer is used to compute local similarity of the S1 and S2 data and to compute a cumulative time-difference by which the S2 data lags the S1 data from the local similarity. Based on the computed cumulative time-difference, the fracture density of a subsurface formation is estimated.

Abstract: Apparatus, computer instructions and method for deghosting seismic data related to a subsurface of a body of water. The method includes inputting data recorded by detectors that are towed by a vessel, the data being associated with waves travelling from the subsurface to the detectors; applying a migration procedure to the data to determine a first image of the subsurface; applying a mirror migration procedure to the data to determine a second image of the subsurface; joint deconvoluting the first image and the second image for deghosting a reflectivity of the subsurface; and generating a final image of the subsurface based on the deghosted reflectivity of the joint deconvoluting step.

Abstract: A data set representing features of a geologic formation is formed from two or more signal acquisition data set representing independent aspects of the same wavefield. A wavelet transform is performed on the two or more signal acquisition data sets, and the data sets are further transformed to equalize signal portions of the data sets. Remaining differences in the data sets are interpreted as excess noise and are removed by different methods to improve the signal-to-noise ratio of any resulting data set.

Abstract: Circuitry for ultrasound devices is described. A multilevel pulser is described, which can provide bipolar pulses of multiple levels. The multilevel pulser includes a pulsing circuit and pulser and feedback circuit. Symmetric switches are also described. The symmetric switches can be positioned as inputs to ultrasound receiving circuitry to block signals from the receiving circuitry.

Abstract: A hydrophone has a pair of end caps each disposed on a different open end of an air-backed cylinder of a piezoelectric ceramic material. An electrode or lead extends through one of the end caps and into the cylinder, and has a shape and a lateral width that extends across an interior of the cylinder and abuts an inner surface of the cylinder at multiple points.

Abstract: As may be implemented in accordance with one or more embodiments, an apparatus and/or method involves a plurality of transducer elements that convert energy waves conveyed via a multi-directional radiation pattern into electrical charge. A power-accumulation circuit accumulates electrical charges from each of the plurality of transducer elements, with each of the transducer elements being arranged at different respective off-axis angles relative to an axis at which the energy is being conveyed. The power-accumulation circuit accumulates energy from each of the individual energy-transduction areas, such that energy received at different respective off-axis angles contributes to the accumulation of electrical charge.

Abstract: Time lapse or 4D seismic data are corrected for geologic overburden and seismic recording system effects. The data from a survey at one time of interest is processed within a selected frequency band and the reservoir level is normalized by the overburden. The results are used to extract reservoir amplitudes from the data of that same survey. Frequencies where overburden signal-to-noise ratios vary dramatically between time lapse surveys may then be avoided in processing of data from the area of interest.

Abstract: Disclosed herein is an apparatus for detecting infrasound. The apparatus for detecting infrasound includes a sound wave detector including a diaphragm dividing an inner space of a first container into a first space and a second space, and a microchannel assembly including a second container having an inner space with one of the spaces divided by the diaphragm and a plurality of microchannels having different resistance values with respect to transmission of a sound wave, and exposing the inner space of the second container to the air through one of the plurality of microchannels. Such an apparatus for detecting infrasound may have various cut-off frequencies according to the number of the microchannels.

Abstract: Calibration apparatus including a pressure cap and a pressure base that define a pressure chamber that is fillable with a liquid. A reference sensor and a sensor under test are exposed to acoustic pressures in the liquid, and responses measured. The sensor under test is secured through one of the pressure cap or base, and responses measured at acoustic frequencies as low as 0.001 Hz and at hydrostatic pressures of at least 5000 psi.

Abstract: A system and a method for determining one or more wave characteristics from a moving platform are disclosed. A sonar system, such as an Acoustic Doppler Current Profiler, can profile the water motion relative to the platform, and an earth reference can determine a measure of the platform motion relative to a fixed earth reference. Both water profile and earth reference measurements can be synergistically employed to compensate for motion of the platform. Directional wave spectra and non-directional wave spectrum can be computed and translated via linear wave theory to surface height spectra and used to calculate characteristics, such as significant wave height, peak period, and peak direction.

Abstract: An object information acquisition apparatus according to an embodiment of the present invention includes a plurality of transducer elements each configured to transmit an acoustic wave to an object, to receive reflected waves reflected from inside the object, and to convert the reflected waves into a time-series reception signal; and a processor configured to perform frequency domain interferometry combined with adaptive signal processing by using the reception signals output from the plurality of transducer elements and a reference signal so as to obtain acoustic characteristics at a plurality of positions located inside the object. The processor is configured to switch the reference signal to another reference signal at least once in accordance with a target position located inside the object while performing the frequency domain interferometry so as to obtain the acoustic characteristics at the plurality of positions located inside the object.

Abstract: A high performance computing strategy along with the capability to integrate various layers of data within a modeling framework incorporates various tools such as ambient noise, vessel and animal data to measure acute and chronic noise levels, detect and classify marine mammal vocalizations, and compute various metrics such as receive levels, signal excess, masking and communication space over relatively large temporal and spatial scales.

Abstract: A synthetic underwater visualization system (SUVS) comprising a real-time graphics software engine, a sophisticated underwater environmental sensor, a fixed-base database, and a retrieval system designed to accept and assimilate into a common database bathymetric and environmental information acquired from around the world by components of other deployed SUVS sensing systems. SUVS is capable of sensing, modeling, and realistically displaying underwater environments in real-time, and will foster widespread utilization in the areas of homeland security, commercial and recreational maritime navigation, bathymetric data collection, and environmental analysis. The technology will also be readily adaptable and highly desirable in non-marine applications.

Abstract: The invention relates to a method for operating at least one ultrasonic sensor (4, 6) of a driver assistance system (2) in a motor vehicle (1), wherein an output sound signal (SA) of the ultrasonic sensor (4, 6) is modulated in accordance with a type of modulation and by means of this modulation, a specific codeword is impressed on the output sound signal (SA). For at least two mutually different functionalities (8 to 12) of the driver assistance system (2), different types of modulation are in each case used for the modulation of the output sound signal (SA) and/or in each case different lengths of the codeword.