A photo acoustic non-destructive measurement apparatus and method for quantitatively measuring texture of a food snack is disclosed. The apparatus includes a laser generating tool, an acoustic capturing device, and a data processing unit. The laser generating tool directs a laser towards a food snack placed on a surface and creates pressure waves that propagate through the air and produce an acoustic signal. The acoustic capturing device records and forwards the signal to a data processing unit. The data processing unit further comprises a digital signal processing module that processes the received acoustic signal. A statistical processing module further filters the acoustic signal from the data processing unit and generates a quantitative acoustic model for texture attributes such as hardness and fracturability. The quantitative model is correlated with a qualitative texture measurement from a descriptive expert panel. Texture of food snacks are quantitatively measured with the quantitative acoustic model.

A photo acoustic non-destructive measurement apparatus and method for quantitatively measuring texture of a food snack is disclosed. The apparatus includes a laser generating tool, an acoustic capturing device, and a data processing unit. The laser generating tool directs a laser towards a food snack placed on a surface and creates pressure waves that propagate through the air and produce an acoustic signal. The acoustic capturing device records and forwards the signal to a data processing unit. The data processing unit further comprises a digital signal processing module that processes the received acoustic signal. A statistical processing module further filters the acoustic signal from the data processing unit and generates a quantitative acoustic model for texture attributes such as hardness and fracturability. The quantitative model is correlated with a qualitative texture measurement from a descriptive expert panel. Texture of food snacks are quantitatively measured with the quantitative acoustic model.

A part (120) may be subjected to both a resonance inspection and a surface vibration inspection. Various protocols (230; 240; 250; 280; 260) are disclosed as to how the results of one or more of these inspections may be used to evaluate the part (120).

An apparatus for monitoring a mechanical system comprising a moving surface arranged to undertake periodic motion, the periodic motion having a time period. The apparatus comprises a controller configured to: control a first transducer to emit acoustic waves onto the moving surface during first and second time periods of the periodic motion; receive signals generated by the first transducer or a second transducer, wherein the received signals represent one or both of i) reflections of the acoustic waves from the moving surface and ii) acoustic waves having travelled through the mechanical system; process the received signals to obtain at least one first measurement indicative of a signal received during the first time period, and to obtain at least one second measurement indicative of a signal received during the second time period; compare the at least one first measurement with the at least one second measurement to determine a change of a property of the mechanical system.

A system and method for measuring the vibrations of a test object, such as a machine shaft or other rotating equipment. The system includes a probe sensor fitting having an ultrasonic speaker and an ultrasonic microphone. The probe sensor fitting includes a temperature and relative humidity sensor. The system further includes a probe analyzer circuit with microcomputer that generates vibration analysis data and probe health diagnostics.

The invention presents methods and instrumentation for measurement or imaging of a region of an object with waves of a general nature, for example electromagnetic (EM) and elastic (EL) waves, where the material parameters for wave propagation and scattering in the object depend on the wave field strength. The invention specially addresses suppression of 3.sup.rd order multiple scattering noise, referred to as pulse reverberation noise, and also suppression of linear scattering components to enhanced signal components from nonlinear scattering. The pulse reverberation noise is divided into three classes where the invention specially addresses Class I and Class II 3.sup.rd order multiple scattering that are generated from the same three scatterers, but in opposite sequence.

A photo acoustic non-destructive measurement apparatus and method for quantitatively measuring texture of a food snack is disclosed. The apparatus includes a laser generating tool, an acoustic capturing device, and a data processing unit. The laser generating tool directs a laser towards a food snack placed on a surface and creates pressure waves that propagate through the air and produce an acoustic signal. The acoustic capturing device records and forwards the signal to a data processing unit. The data processing unit further comprises a digital signal processing module that processes the received acoustic signal. A statistical processing module further filters the acoustic signal from the data processing unit and generates a quantitative acoustic model for texture attributes such as hardness and fracturability. The quantitative model is correlated with a qualitative texture measurement from a descriptive expert panel. Texture of food snacks are quantitatively measured with the quantitative acoustic model.

The present invention relates to a pre-collapsed capacitive micro-machined transducer cell (10) comprising a substrate (12), and a membrane (14) disposed above a total membrane area (Atotal), wherein a cavity (20) is formed between the membrane (14) and the substrate (12), the membrane comprising a hole (15) and an edge portion (14a) surrounding the hole (15). The cell (10) further comprises a stress layer (17) on the membrane (14), the stress layer (17) having a predetermined stress value with respect to the membrane (14), the stress layer (17) being adapted to provide a bending moment on the membrane (14) in a direction towards the substrate (12) such that the edge portion (14a) of the membrane (14) is collapsed to the substrate (12). The present invention further relates to a method of manufacturing such pre-collapsed capacitive micro-machined transducer cell (10).

A system and method for monitoring intensive properties in an extreme environment, such as a boiler or other hostile temperature. The intensive properties include temperature, temperature, elasticity, density, strength, and any other properties which effect changes in the ultrasound propagation velocity. The system has one or more fibers ultrasonically communicating with a transducer which emits ultrasonic pulses throughout the fiber. The fibers are circumscribed by echogenic features, each of which returns ultrasonic echo pulses to the transducer at discernable propagation velocities. Changes in the propagation velocities/times correspond to changes in the intensive property under consideration.

The provided is a temperature measurement method based on laser deflection induced by ultrasonic pulse. The method includes the following steps: S1, emitting a continuous laser beam by a continuous laser, and collimating the laser beam by a collimator; S2, the laser beam passes through a high-temperature gas to be measured; S3, the laser beam folds back and again passes through the high-temperature gas to be measured, and then received by a quadrant photodiode; S4, arranging a pulse ultrasonic generator in a vertical direction of the laser beam, and carrying out control by an ultrasonic generator control box; S5, the ultrasonic successively passes through the laser beams at different distances from the pulse ultrasonic generator, and obtaining a generated deflection position information of the laser beams by the quadrant photodiode; S6, analyzing the voltage signal of the quadrant photodiode obtained by step S5.