An inline source can be used for a marine survey. For example, a marine survey vessel can tow source units in line. The source units can be actuated near-continuously to cause a respective signal emitted by each of the source units to be uncorrelated with signals emitted by other of the source units.

An acoustic transducer includes a substrate element having a first side, and a second side opposite the first side. The acoustic transducer also includes first and second piezoelectric elements coupled to the first side, and third and fourth piezoelectric elements coupled to the second side. The first piezoelectric element has a first polarity, and the second piezoelectric element has a second polarity different than the first polarity. The third piezoelectric element has a third polarity, and the fourth piezoelectric element has a fourth polarity different than the third polarity.

This disclosure relates to systems and techniques for identifying collisions, such as relatively low energy impact collisions involving an autonomous vehicle. Sensor data from a first sensor modality in a first array may be used to determine a first estimated location of impact and second sensor data from a second sensor modality in a second array may be used to determine a second estimated location of impact. A low energy impact event may be configured when the first estimated location of impact corresponds to the second estimated location of impact.

The present disclosure is directed to a MEMS-based rotation sensor for use in seismic data acquisition and sensor units having same. The MEMS-based rotation sensor includes a substrate, an anchor disposed on the substrate and a proof mass coupled to the anchor via a plurality of flexural springs. The proof mass has a first electrode coupled to and extending therefrom. A second electrode is fixed to the substrate, and one of the first and second electrodes is configured to receive an actuation signal, and another of the first and second electrodes is configured to generate an electrical signal having an amplitude corresponding with a degree of angular movement of the first electrode relative to the second electrode. The MEMS-based rotation sensor further includes closed loop circuitry configured to receive the electrical signal and provide the actuation signal. Related methods for using the MEMS-based rotation sensor in seismic data acquisition are also described.

A computer-implemented method, and system implementing the method, are disclosed for computing a final model of elastic properties, using nonlinear direct prestack seismic inversion for Poisson impedance. User inputs and earth-model data is obtained over points of incidence of a survey region, at various angles of incidence. Various models are then computed that serve for lithology identification and fluid discrimination and take part in preliminary seismic exploration and reservoir characterization. Therefore, further refinement of these models is required due to changes in burial depths, compaction and overburden pressure, as they provide limitations for reservoirs on porous media. The further refinement using nonlinear direct prestack seismic model is performed on a system computer, which produces a final model of elastic properties. This model can then be applied for lithology prediction and fluid detection to identify potential targets of oil and gas exploration and estimating spots in unconventional shale gas applications.

The present disclosure provides a small, inexpensive, long-lived underwater beacon locator. The beacon locator can illustratively include a housing, a communications link, a processor, a plurality of hydrophones and a motion generator.

A device and method for receiving real-time warning messages about a hazardous situation, for which an alert or a mitigating control action may be warranted, with the means to measure the effects forecasted by the parameters contained in the warning messages, adjust the parameters to more accurately reflect local conditions, and provide feedback about the performance and accuracy of the system sending the warning messages.

An ultrasonic sensor is provided with a sensor body, a cushion member, a retainer part and a waterproof seal. The sensor body has an ultrasonic microphone and a microphone support part. The cushion member covers a protrusion part of the ultrasonic microphone. The retainer part sandwiches a sandwiched part on a proximal end side between the retainer part and an outer peripheral surface of the ultrasonic microphone, while exposing an exposed part on a tip end side in the axial direction of the cushion member. The waterproof seal blocks a gap between a vehicle body component and the exposed part of the cushion member in an on-board state.

Sensors on an aerial lift device determine the number of occupants in and occupant portion of the aerial lift device. Prior to permitting the occupant portion to rise up off the ground, the system checks the engagement of safety harnesses to verify that the number of engaged safety harnesses matches the number of occupants in the occupant portion of the aerial lift. If the number matches, operation of the aerial lift may be enabled and the occupant portion deployed. If the number does not match, an alarm is sounded and deployment of the occupant portion may be disabled. With pre-deployment safety testing, and no occupants in the occupant portion, the occupant portion may be deployed to verify all operational status of the occupant portion with no occupants. The system may further create a data log to verify the time and successful pre-deployment safety check.

A system for evaluating a characteristic of a portion of a building space, such as a room, may be provided. The system includes pairs of speakers and microphones associated with detection areas and forming audio multipath transmission channels. The system includes a controller communicatively coupled to the speakers and the microphones. The controller is configured to: (1) select detection areas; (2) activate the microphones corresponding to the pairs associated with the selected detection areas to capture one or more audio samples; (3) select speakers based on a baseline channel response matrix and the activated microphones; (4) transmit command signals to the selected speakers; (5) determine a characteristic channel response matrix based on the audio samples and audio signals corresponding to the command signals; and (6) evaluate the characteristic of the portion of the building space based on the characteristic channel response matrix and the baseline channel response matrix.