A gas sensor for detecting a gas in an environment is disclosed. The gas sensor comprises a housing having a cavity and a vent hole within the housing and a distributed element resonator within the cavity. The cavity includes a bottom surface and a top surface, and the housing is configured to receive the gas from the environment into the cavity through the vent hole. The distributed element resonator has an input terminal configured to receive a radio frequency input signal and an output terminal configured to produce an output signal.

A method for predicting a telemetry mode of a downhole tool includes receiving a signal from the downhole tool at a computing system at a surface. The method also includes predicting the telemetry mode of the downhole tool based on the signal. The method also includes switching a telemetry mode of the computing system to match the telemetry mode of the downhole tool. The method also includes demodulating the signal using the computing system after the telemetry mode of the computing system has been switched.

A method for predicting a telemetry mode of a downhole tool includes receiving a signal from the downhole tool at a computing system at a surface. The method also includes predicting the telemetry mode of the downhole tool based on the signal. The method also includes switching a telemetry mode of the computing system to match the telemetry mode of the downhole tool. The method also includes demodulating the signal using the computing system after the telemetry mode of the computing system has been switched.

An apparatus for equipment monitoring includes an input unit, a processing unit, and an output unit. The input unit is configured to provide the processing unit with batches of temporal sensor data for an item of equipment. Each batch of temporal sensor data includes temporal sensor values as a function of time. The processing unit is configured to process the batches of temporal sensor data to determine batches of spectral sensor data. Each batch of spectral sensor data includes spectral sensor values as a function of frequency. The processing unit is configured to implement at least one statistical process algorithm to process the spectral sensor values for the batches of spectral sensor data to determine index values. For each batch of spectral sensor data there is an index value determined by each of the statistical process algorithms.

A method of detecting an event within a wellbore includes obtaining a sample data set, determining a plurality of frequency domain features of the sample data set, comparing the plurality of frequency domain features with an event signature, determining that the plurality of frequency domain features matches the thresholds, ranges, or both of the event signature, and determining the presence of the event within the wellbore based on determining that the plurality of frequency domain features match the thresholds, ranges, or both of the event signature. The sample data set is a sample of an acoustic signal originating within a wellbore including a fluid. The sample data set is representative of the acoustic signal across a frequency spectrum. The event signature includes a plurality of thresholds, ranges, or both corresponding to the plurality of frequency domain features.

A method of detecting an event within a wellbore includes obtaining a sample data set, determining a plurality of frequency domain features of the sample data set, comparing the plurality of frequency domain features with an event signature, determining that the plurality of frequency domain features matches the thresholds, ranges, or both of the event signature, and determining the presence of the event within the wellbore based on determining that the plurality of frequency domain features match the thresholds, ranges, or both of the event signature. The sample data set is a sample of an acoustic signal originating within a wellbore including a fluid. The sample data set is representative of the acoustic signal across a frequency spectrum. The event signature includes a plurality of thresholds, ranges, or both corresponding to the plurality of frequency domain features.

In an abnormal noise evaluation system, running noise of a vehicle is acquired, and the running noise is analyzed to generate analysis data. A rotational order component of the running noise of the vehicle is then extracted from the analysis data, and features for each rotational order of the running noise of the vehicle is generated based on the extracted rotational order component. Subsequently, a learning model is generated using as training data a combination of the features for each rotational order generated for a learning object that is of the same type as an object to be evaluated and an evaluation result given in advance to the learning object. Whether there is abnormal noise from the object to be evaluated is evaluated by applying the features for each rotational order generated for the object to be evaluated to the learning model, and an evaluation result is output.

Methods of processing a data signal obtained from a sensor sensing a dynamic signal to detect a structural anomaly event are disclosed. In one embodiment, a method includes obtaining signal components attributable to fluid flow at a location within an operational pipeline network; processing the data signal to extract one or more features; characterising the one or more extracted features; and detecting an indication of a structural anomaly event proximal the location depending on the characterisation; wherein the structural anomaly event includes an occurrence and/or further development of a structural anomaly.

A direct field acoustic testing system comprising a control microphone, a controller operatively coupled to the control microphone such that the controller receives at least one input signal from the control microphone, and a plurality of acoustic transducer groups receiving an electronic signal from the controller, each transducer group including at least one acoustic transducer. An average power density of the direct field acoustic testing system for a pre-determined acoustic test spectrum being equal to or greater than 46 acoustic watts per square meter of total active acoustic transducer radiating surface area.

A gas sensor for detecting a gas in an environment is disclosed. The gas sensor comprises a housing having a cavity and a vent hole within the housing and a distributed element resonator within the cavity. The cavity includes a bottom surface and a top surface, and the housing is configured to receive the gas from the environment into the cavity through the vent hole. The distributed element resonator has an input terminal configured to receive a radio frequency input signal and an output terminal configured to produce an output signal.