This application relates to a method of analyzing dynamic characteristics of a carbon composite material. This application also relates to a method of calculating sensitivity indices for structural stiffness and a viscous damping coefficient of a carbon composite material and a method of analyzing dynamic characteristics of a carbon composite material by using the same. Respective sensitivity indices for structural stiffness and a viscous damping coefficient according to a direction (angle) of carbon fiber for a carbon composite material are calculated. A change in the dynamic characteristics of the carbon composite material is evaluated through a proportional relationship between the sensitivity indices, thereby conducting a more accurate and efficient analysis.

This application relates to a method of analyzing dynamic characteristics of a carbon composite material. This application also relates to a method of calculating sensitivity indices for structural stiffness and a viscous damping coefficient of a carbon composite material and a method of analyzing dynamic characteristics of a carbon composite material by using the same. Respective sensitivity indices for structural stiffness and a viscous damping coefficient according to a direction (angle) of carbon fiber for a carbon composite material are calculated. A change in the dynamic characteristics of the carbon composite material is evaluated through a proportional relationship between the sensitivity indices, thereby conducting a more accurate and efficient analysis.

Methods, systems, and apparatus, including computer programs encoded on computer-storage media, for self-calibrating ultrasonic removal of sea lice. In some implementations, a method includes generating, by transducers distributed in a sea lice treatment station, a first set of ultrasonic signals, detecting a second set of ultrasonic signals in response to propagation of the first set of ultrasonic signals through water, determining propagation parameters of the sea lice treatment station based on the second set of ultrasonic signals that were detected, obtaining an image of a sea louse on a fish in the sea lice treatment station, determining, from the image, a location of the sea louse in the sea lice treatment station, and generating a third set of ultrasonic signals that focuses energy at the sea louse.

The electromagnetic ultrasonic transducer includes a detection bottom surface and a stopper connected to a sidewall of the electromagnetic ultrasonic transducer; wherein the stopper extends towards the detection bottom surface; a bottom surface of the stopper is lower than the detection bottom surface; a distance “d” between the bottom surface of the stopper and the detection bottom surface is in a range 0 mm<d≦1 mm; the bottom surface of the stopper contacts a surface of an object to be detected in a working state of the electromagnetic ultrasonic transducer.

The electromagnetic ultrasonic transducer includes a detection bottom surface and a stopper connected to a sidewall of the electromagnetic ultrasonic transducer; wherein the stopper extends towards the detection bottom surface; a bottom surface of the stopper is lower than the detection bottom surface; a distance “d” between the bottom surface of the stopper and the detection bottom surface is in a range 0 mm<d≦1 mm; the bottom surface of the stopper contacts a surface of an object to be detected in a working state of the electromagnetic ultrasonic transducer.

When frequencies used in the two-frequency measurement of a SAW sensor are represented by f.sub.1 and f.sub.2 (f.sub.2>f.sub.1), an electrical signal processing device is provided without use of oversampling at a frequency higher than twice the frequency f.sub.2 or a two-system low-frequency conversion circuit, in which temperature compensation with the same accuracy as the case where these are used can be realized. Narrow band frequency filtering is applied to a waveform after roundtrips in a delay line type SAW sensor capable of transmitting and receiving multiple frequencies, the two frequencies f.sub.1 and f.sub.2 (f.sub.2>f.sub.1) are extracted, and a delay time is determined utilizing an aliasing obtained by applying undersampling at a frequency lower than twice the frequency f.sub.1.

The invention comprises a device (10) for testing a test object (40), comprising an excitation system (13) for generating broadband ultrasound pulses (12′) in the test object, a detection system (20) for detecting ultrasound waves (21), which are generated through the broadband ultrasound pulses (12′) in the test object (40) and emitted by the test object (40). The device (10) comprises a processing unit (30) for processing the detected ultrasound waves (21), while the excitation system (13) being one of a thermoacoustic emitter or a pulsed laser and the detection system (20) is a broadband detection system. The excitation system (13) comprises a modulator (11) for modulating the broadband ultrasound pulses (12′). Furthermore, the invention comprises a method for testing a test object.

A NEMS readout system includes a sensor array comprising a plurality of sensors. Each sensor of the plurality of sensors including a resonator with frequency characteristics different from the resonator of each other sensor of the plurality of sensors. A readout signal indicative of a plurality of output signals is collected from the sensor array. Each output signal of the plurality of output signals corresponding to one of the plurality of sensors. An analysis of the plurality of output signals is performed to identify a plurality of resonant frequencies and to detect a frequency shift associated with at least one of the plurality of resonant frequencies.

A system for nondestructive testing of a composite includes a emitter that transmits a plurality of sound signals to a composite at over a range of frequencies and receives sound signals from the composite, and generates electric signals in response to the received signals; a computer control for receiving the electric signals from the emitter, wherein the computer control programmed to apply a different, preset gain setting to at least one of the plurality of frequencies for a selected display image such that the display image shows a plot of received signal amplitude for the plurality of frequencies that is at least partially flattened, so that the amplitude of the signal from material without defects is the same at all frequencies, and changes in the amplitude of the signal are visually perceptible on the display for all of the plurality of signals.

A system for nondestructive testing of a composite includes a emitter that transmits a plurality of sound signals to a composite at over a range of frequencies and receives sound signals from the composite, and generates electric signals in response to the received signals; a computer control for receiving the electric signals from the emitter, wherein the computer control programmed to apply a different, preset gain setting to at least one of the plurality of frequencies for a selected display image such that the display image shows a plot of received signal amplitude for the plurality of frequencies that is at least partially flattened, so that the amplitude of the signal from material without defects is the same at all frequencies, and changes in the amplitude of the signal are visually perceptible on the display for all of the plurality of signals.