Abstract: A single-input multi-output surface acoustic wave (“SAW”) device contains two or more output inter-digital transducers (“IDTs”) arranged in a longitudinal direction of a single input IDT. The detection sensitivity and reliability of the SAW device may be improved by eliminating the deviation and signal interference between multiple input IDTs.

Abstract: A method for monitoring and controlling the thickness of coating on a creping cylinder is disclosed. The methodologies involve a coordinated scheme of apparatuses that function to monitor various aspects of a creping cylinder coating so that the thickness of the coating can be determined.

Abstract: Apparatus and method for non-invasive measuring of the sound velocity of a fluid, such as a liquid, flowing in a tubing having points of two different and known transverse length has one sensor mounted at each point connected to a circuit that provides signals to each sensor that are returned to it after passing through the tubing wall and flowing fluid and reflection from the tubing internal wall opposing each sensor and from which the round trip transit time of the signals is measured and the sound velocity calculated from the two measured round trip transit times and the differential between the known transverse lengths. Flexible tubing is placed in the slot of a measuring head which deforms it to provide the two points at one location or the slot has two sections of different transverse length along its length with a point at each section.

Abstract: An image generating apparatus of the present invention has a determination unit that sets a target area in a part of an area inside a subject, executes processing to adjust a phase of each detection signal based on a distance from each detection element to a target area and a tentative velocity, and calculate dispersion of intensities of a plurality of detection signals of which phases are adjusted, for a plurality of tentative velocities, and determines a velocity for which dispersion of intensities is minimum, out of the plurality of tentative velocities, as a propagation velocity.

Abstract: An acoustic apparatus adapted to operate in a gas filled space from a first side of an object to be measured for making a non-contact thickness measurement thereof includes an electro acoustic transducer, a transceiver coupled with the electro acoustic transducer and adapted to excite electro acoustic transducer to output an acoustic signal towards the object to be measured and receive an acoustic response signal therefrom, and a signal processor adapted to process the response signal and determine a thickness of the object. The electroacoustic transducer has a transducer-to-gas acoustic interface, and the transceiver is adapted to operate the electroacoustic transducer so as to emit into a gas filled gap an acoustic broad band pulse towards the object and to receive an acoustic resonance response signal in the acoustic response signal at a level that allows acquisition of the resonance response signal above a predetermined signal to noise level.

Abstract: A method of assessing bolted joint integrity. A guided wave is sent through a structure containing at least one bolted joint. The guided wave that is subsequently propagated through the structure and interacted with the bolted joint is measured to obtain a measured result. At least one parameter of the guided wave after its travel through the structure, and after having been affected by a nonlinear acoustic behavior of the bolted joint, is analyzed. Either at least one guided wave parameter is compared to a wave propagation pattern of the bolted joint at a correct torque level, or variation of at least one guided wave parameter is compared, to determine changes in wave propagation time and/or wave propagation shape. An incorrect torque level of the bolted joint is inferred from any changes that are determined.

Abstract: A sensing assemblage (1) for capturing a transit time, phase, or frequency of energy waves propagating through a medium is disclosed to measure a parameter of the muscular-skeletal system. The sensing assemblage (1) comprises a transducer (2) and a waveguide (3). The transducer (2) is coupled to the waveguide (3) at a first location. A second transducer (11) can be coupled to the waveguide (3) at a second location. An interface material that is transmissive to acoustic energy waves can be placed between transducers (402, 404) and a waveguide (414) to improve transfer. The interface material (408, 410) can affix the transducers (402, 404) to the waveguide (414). Alternatively, a reflecting feature (5) can be placed at a second location of the waveguide (3) to reflect acoustic waves back to the transducer (2) where transducer (2) emits energy waves into the medium and detects propagated energy waves.

Abstract: The invention relates to a method for investigating a structure and a structure for receiving and/or conducting a liquid or soft medium, the method comprising the steps of: a) exciting acoustic waves in the structure by means of at least one transmitter, b) converting at least a part of the energy associated with the acoustic waves (A) excited in the structure into volume sound waves of the medium, c) reconverting at least a part of the energy associated with the volume sound waves into acoustic wave energy of the structure thereby generating acoustic waves in the structure, d) receiving acoustic waves evoked by the transmitter by at least one receiver, and e) verifying whether a coating is present on a surface of the structure and/or if a coating is present determining properties of the coating by evaluating a signal generated by the receiver upon receipt of acoustic waves evoked by the transmitter and/or verifying whether a level of the medium (5) is below a predetermined value.

Abstract: Methods and apparatus for exciting a structure and determining its structural integrity. In particular, methods of nonlinear analysis are used to compare first and second response datasets, each dataset resulting from a different excitation amplitude that the other dataset.

Abstract: The present invention provides a system and method for a milk measuring device for measuring the acoustic properties, such as acoustic damping and sound velocity in milk, in order to determine milk properties. The sound velocity in milk depends on temperature and composition. By carrying out, for example by means of a piezo element, a reference measurement on vibrations that have been directed by a second piezo element into a wire or the like of known material, which wire is strung in the measuring chamber which is filled with the milk to be tested, the milk temperature can be derived, so that other milk properties, in particular the fat/protein composition, can be determined in a more reliable manner.

Abstract: The timing of obtaining an output value for use in a determination of a recording medium is generated from a received ultrasonic wave and a waveform generated by delaying the ultrasonic wave, whereby it is possible to reduce an influence of a reflection wave from the peripheral members and an influence of a change in the environment to improve the accuracy of determination of the recoding medium.

Abstract: A method for monitoring fluid flow through a downhole device, comprises a) providing an acoustic tube wave in fluid in the device; b) measuring the acoustic tube wave after it has passed through the fluid in the device; and c) assessing the permeability of the device by measuring the attenuation of the acoustic signal. Changes in velocity of the acoustic signal may also be measured. The device may be a permeable downhole device such as a sand screen the measurements in step b) are made using a plurality of sensors deployed in the hole. The method may further including the step of cross-correlating a signal received at a first receiver with signals received at additional sensors so as to obtain an effective response as if the signal had been emitted from a source at the position of said first receiver.

Abstract: Methods and apparatus relate to ultrasound measurement of a dimension such as the thickness (11) of an item (12) which may be worn over time by contact with an item (14). An ultrasonic transceiver (18) couples ultrasound into the item (12). Outgoing ultrasound i results in echos r returning to the transceiver (18). This allows calculation of time of flight to yield a value for the thickness (11). In the examples prescribed, the measurement is repeated a plurality of times in a specified period to extract a dimension from each received signal. Information extracted from the plurality of received signal is used to produce a single value indicative of the dimension of the item (12) over the specified period.

Abstract: A dialysis system that includes a dialysis machine, a tube connected to the dialysis machine, and a sensor system. The sensor system includes a head having a slot configured to receive the tube and a plurality of sensors secured to the head adjacent the slot. At least one of the plurality of sensors includes a light emitting element configured to transmit light through the tube when the tube is disposed in the slot and a light receiving element configured to receive the light emitted by the light emitting element after the light passes trough the tube.

Abstract: A method and apparatus for measuring frequency and amplitude of an input signal representative of an echolocation call. In one example, a system includes a combination of a digital sampling channel and a zero crossing measurement channel that are configured to simultaneously measure the echolocation call and produce a combined, time-synchronous data set representative of the echolocation call.

Abstract: A transducer is used to send an ultrasound pulse toward a stone and to receive ultrasound reflections from the stone. The recorded time between a pulse that is reflected from the proximal surface and a pulse that is reflected either from the distal surface of the stone or from a surface supporting the stone is used to calculate the stone size. The size of the stone is a function of the time between the two pulses and the speed of sound through the stone (or through the surrounding fluid if the second pulse was reflected by the surface supporting the stone). This technique is equally applicable to measure the size of other in vivo objects, including soft tissue masses, cysts, uterine fibroids, tumors, and polyps.

Abstract: An EMUS transducer system for producing linearly polarized transverse waves having a variably predeterminable polarization direction within a test specimen containing at least ferromagnetic material portions and having a test specimen surface, a magnetization unit produces a magnetic field orientated parallel to the test specimen surface within the test specimen. At least one HF coil on the test specimen surface produces or detects a HF field combined with the magnetic field orientated parallel to the test specimen surface within the test specimen. The magnetization unit includes at least three magnetization bodies spatially separated from one another to introduce a magnetic field into the test specimen. The magnetic flux emanating from at least one of magnetization bodies a spatial direction relative to the test specimen surface is varied.

Abstract: A method for acoustically sensing an area is described. An acoustic transmit pulse is transmitted into the area by an acoustic transducer and a received signal is acquired with the aid of the transducer, in order to receive the transmit pulse reflected back from the area. Within a post-pulse oscillation time of the transducer, which directly follows the emission of the transmit pulse, the actual phase response of the received signal is determined. In the event the actual phase response deviates from a predefined setpoint phase response, an object is detected within the area. Also described is a device for acoustically sensing an area, which is designed to carry out the method.

Abstract: A method for determining the fibre orientation in a fibre-reinforced component having a number of fibres distributed in a laminate material is provided. The fibres are orientated in at least one defined direction. An ultrasonic signal is emitted into the component by an ultrasonic transducer. A reflected ultrasonic signal is received by an ultrasonic receiver and a measurement signal is generated. The ultrasonic transducer and the ultrasonic receiver are disposed in a defined linear relationship. Information is determined indicating a degree of the fibre orientation in relation to the defined linear relationship of the ultrasonic transducer and the ultrasonic receiver from the respective measurement signal.

Abstract: A quantitative evaluation method, a method for manufacturing a silicon wafer, and a silicon wafer manufactured by the method, enabling more efficient evaluation of the concentration of atomic vacancies existing in a silicon wafer. The quantitative evaluation method includes steps of: oscillating, in a state in which an external magnetic field is applied to a silicon wafer (26) while keeping the silicon wafer (26) at a constant temperature, an ultrasonic wave pulse and receiving a measurement wave pulse obtained after the ultrasonic wave pulse is propagated through the silicon wafer (26) for detecting a phase difference between the ultrasonic wave pulse and the measurement wave pulse; and calculating an elastic constant from the phase difference. The external magnetic field is changed to calculate the elastic constant corresponding to a change in the external magnetic field for evaluating a concentration of atomic vacancies in the silicon wafer (26).

Abstract: An ultrasonic position sensing system is disclosed. In one embodiment, the system includes an ultrasonic sensor configured to monitor the position of a device. The system also includes ranging logic. The sensor is controlled by the logic to direct an ultrasonic pulse toward the device. The logic is configured to compute the transit time and the velocity of the ultrasonic pulse. Based on these parameters, the logic computes the path length between the sensor and the device, which corresponds to the location of the device relative to the location of the sensor. In further embodiments, the ultrasonic positioning system may include multiple sensors in communication with the ranging logic for monitoring multiple devices.

Abstract: A method for calibration of a thickness gauge is provided in which the thickness gauge measures the thickness of a measured object in a stipulated measurement direction with at least one displacement sensor, operating contactless or by scanning, a reference object with known thickness and shape being brought into at least one partial area of the measurement field of the at least one displacement sensor.

Abstract: An improved system and method for automatically inspecting the quality of newly-manufactured containers is disclosed that detects containers that are out-of-round by more than a predetermined amount so that they may be rejected to ensure that containers that are passed are of acceptable quality. One or more ultrasonic sensors are located at fixed positions with reference to a container that is rotated. If any sensor detects that the distance between the sensor and the container falls outside of an acceptable range, the container is rejected.

Abstract: Switching a transmitting and receiving direction of two transducers (2,3) in the forward and the reverse direction, a time differential memory part (17b) storing a propagation time differential every K times a unit measurement process being executed, the propagation time differential being a differential between a propagation time of the ultrasonic wave signal in a forward direction and in a reverse direction, a flow rate calculating part (15) calculating a flow rate of a passing fluid based on a lump sum of propagation times in both the forward and the reverse directions obtained at least every K times of a unit measurement process being executed, an estimating part (18) estimating a change in a momentary flow rate of the fluid based on the time differential obtained every K times of the unit measurement process being executed and storing thereof in a time differential memory part (17b), thus obtaining an accurate flow rate and detecting the change in the momentary flow rate.

Abstract: A passage detection apparatus is configured to detect the change in the properties (propagation state of sound wave, dielectric constant, etc.) of a specific space, which changes according to the passage of an object in the specific space and the size of the object. The passage detection apparatus includes a pair of detection units and configured to transmit and receive signals to and from an external device. The specific space is formed by the space between the detection unit and the detection unit. The detection unit is supported by a first substrate. The detection unit is supported by a second substrate that is parallel to the first substrate, and arranged at the position corresponding to the detection unit supported by the first substrate.

Abstract: The invention relates to a method and a device for detecting the solidification behavior of pourable and solidifying masses and/or masses that are to be solidified, in particular of chocolate-type masses, as well as their separation behavior from their delimiting walls that are in contact with these masses, specifically molds. Solutions are offered regarding how to achieve the optimized point in time for demolding and for achieving optimized product surface quality taking into account process orders of magnitude such as cooling temperature, cooling speed and conveyor belt speed.

Abstract: A method for inspecting a laminate structure may include transmitting a lamb wave through a selected portion of the laminate structure from an actuator at a predetermined location on a surface of the laminate structure. The method may also include receiving the transmitted lamb wave at a sensor at another predetermined location on the surface of the laminate structure. The method may additionally include detecting and characterizing an anomaly in the laminate structure based on the received lamb wave.

Abstract: A non-invasive system for detection of explosives and contraband in a vehicle includes at least one laser vibrometer for measuring vehicle vibrations at one or more points on the vehicle while the vehicle is operating. One laser vibrometer can be sequentially directed to various points on the vehicle according to a predetermined single point or pattern. Or, a plurality of laser vibrometers could be used to simultaneously illuminate the vehicle. After measurement, the vehicle vibrations are compared to a database of reference vibrations, which that were taken of similar vehicles that were known to be contraband-free. The measured vibrations are compared to the vibrations pattern for the same type of vehicle. If the vibration patterns exhibit differences in frequency peaks that exceed predetermined parameters, the system alerts the operator. A more detailed inspection of the vehicle can then be accomplished.

Abstract: An apparatus provides for the non-destructive testing of samples. The samples can in this respect also be formed from critical materials which change their properties during manufacture, for example on a hardening or solidification. In an apparatus in accordance with the invention, at least one ultrasonic pressure wave transducer is arranged at a forward cell. The forward cell is filled with a liquid and is placed with an open side at one side onto a surface (A) of a conversion prism, in the form of a solid body, so that the liquid and the surface (A) are in touching contact. The conversion prism is placed with a further surface (B) onto a surface of a sample to be tested. At least one ultrasonic pressure wave transducer can be positioned or is positioned at the forward cell at at least two positions (T1, T2) so that the positions are arranged at an equal spacing from the center of the surface (A) of the conversion prism, said surface being placed onto the sample.

Abstract: Disclosed is a method and apparatus for non-invasive bone fracture detection and accelerated healing, that simultaneously maps, via a paired phased array ultrasound scanning apparatus having multi-element transducers, three dimensional bone surface topology at opposite surfaces along an ultrasound wave pathway; that measures, using the mapped three dimensional topology, a thickness of the mapped bone; that detects, using the mapped three dimensional topology, a region of interest with bone deterioration or fracture; that calculates an ultrasonic wave velocity and attenuation as the ultrasound wave passes through the detected region of interest; and that applies a low-intensity pulsed ultrasound (LIPUS) pulse to the region of interest. The paired phased array ultrasound scanning apparatus focuses the application of the LIPUS pulse.

Abstract: For precisely determining a position of an electronic pen using ultrasonic, only a direct wave arriving first at a reception device is detected without being affected by a reflected wave of an ultrasonic signal to count a propagation time of the electronic pen. An infrared signal including a trigger signal indicative of transmission timing and data indicative of an M-sequence initial condition, and an ultrasonic signal made into an M-sequence are simultaneously sent from the electronic pen in each fixed transmission cycle. The reception device disposed at a predetermined position receives the infrared signal from the electronic pen to generate an M-sequence model waveform from M-sequence initial condition data that the infrared signal includes. The reception device further receives the ultrasonic signal from the electronic pen to calculate a value of correlation between the ultrasonic signal and the above-described M-sequence model waveform.

Abstract: A method and apparatus for identifying an inconsistency. A number of waves that propagate through a structure are generated. A response signal is generated in response to detecting at least a portion of the number of waves that propagate through the structure. A determination is made as to whether the response signal includes a reflected component. A presence of the inconsistency in the structure is indicated when the response signal includes the reflected component.

Abstract: Systems and methods for estimating a physical characteristic of a seafood product are provided. In one system, the estimate is based on a slope defined by a ratio of changes in peak resonant amplitude and frequency of an electromagnetic resonant circuit in loaded and unloaded states. In another system, a first probe of a plurality of probes is driven with a test signal when the plurality of probes is loaded by a seafood product and the estimate is based on received test signals at one or more of the other probes. In another system, the estimate is based on the loading effect of a seafood product on an electromagnetic resonant circuit, which is also used to read an ID from an RFID associated with the seafood product. The systems and methods may be used for individual specimens, or to determine an average estimate for multiple specimens at one time.

Abstract: Methods are provided for analyzing characteristics of fluids in the context of an acoustic ejection system. Such a system has a controller, an acoustic radiation generator, and a coupling medium coupling the radiation to a reservoir holding fluid. The methods can use acoustic radiation to both perturb a surface of the fluid in the reservoir and analyze the effect of the perturbation. The methods may use information about prior fluids. The methods of the invention can determine physical characteristics such as speed of sound and viscosity. The methods also include ways to determine a level of acoustic energy suitable to eject a droplet. Preferably the methods are executed automatically under control of programming of a controller of an acoustic ejection system.

Abstract: According to one embodiment, there is provided with sheet processing device including an ultrasonic wave generator, a detecting array and a judging unit. The ultrasonic wave generator irradiates ultrasonic waves to a sheet being conveyed, from one side of the sheet. The detecting array is arranged in the other side of the sheet and detects sound pressure of the ultrasonic waves passing through the sheet. The judging unit judges a state of the sheet by comparing a predetermined standard value with the sound pressure.

Abstract: An aerodynamically shaped profile member for aircraft and wind power stations includes, for example, phased-array ultrasonic generator arrangement arranged therein. During operation of the profile member, the ultrasonic generator emits ultrasonic waves in a targeted manner in multiple directions to determine a profile of the thickness of an ice layer on the surface of the aerodynamic profile. The structure may be, for example, a composite fiber material arranged around a foam core, with the ultrasonic generator arrangement being laminated into the composite fiber material. For measurement of the ice thickness, ultrasonic waves are transmitted in a targeted manner to different positions of the surface of the aerodynamic profile, and the ultrasonic waves reflected on the interfaces of the ice layer are detected. At least one region of the surface is scanned by means of the targeted ultrasonic waves, to determine an ice thickness profile.

Abstract: A method of determining a steam quality of a wet steam located in an interior of a steam turbine includes emitting from an optical probe a plurality of wavelengths through the wet steam, measuring with the optical probe a wet steam intensity corresponding to each of the plurality of wavelengths emitted through the wet steam, determining an intensity ratio vector by dividing the wet steam intensity by a corresponding dry steam intensity for each of the plurality of wavelengths, successively applying scaling factors to the intensity ratio vector to obtain a scaled intensity ratio vector, calculating a suitable value for each of the scaling factors to obtain a plurality of residuals, determining a minimum residual of the plurality of residuals, determining a droplet size distribution by calculating the droplet number density corresponding to the minimum residual, and determining the steam quality based on the droplet size distribution.

Abstract: As a transmitting horn or a receiving horn attached to a transmission element or a reception element of an ultrasonic sensor, a horn enclosure with two acoustic horn bodies having a dimensional difference ?Lh of a quarter ?/4 of the wavelength ? of an ultrasonic wave U in the propagation direction X of the ultrasonic wave U or a reflection wave R is used. Then, the amplitude of a diffraction wave A1 and the amplitude of a diffraction wave A2 in opposite phase between a transmission side and a reception side are caused to match with each other so as to cancel out both the diffraction waves A1, A2 in a common sound space of the horn enclosure, which is not partitioned for each acoustic horn body by a screen, on a front of the reception element.

Abstract: An operation-position detector having a tube that allows an ultrasonic signal to propagate therethrough. The tube has a plurality of holes capable of being selectively closed or opened by an operation and is provided with an ultrasonic transmitter-receiver arranged at a first end thereof. A signal processor drives the ultrasonic transmitter-receiver and causes an ultrasonic signal to propagate through the inside of the tube, receives a reflection signal corresponding to a closed or open state of each of the holes, and detects the state of each hole on the basis of the reflection signal, thereby detecting the operation position of an operation conducted by an operator.

Abstract: A method and apparatus for testing a bond interface is provided. An initial wave is transmitted into a first end of a first material. The first material is connected to a second material by an adhesive at a bond interface. The first material is dissimilar to the second material. The initial wave splits into a first wave and a second wave at the bond interface. Parameters are changed so a first wave travels through the first material to the first end of the first material and back to the bond interface in a first amount of time and the second wave travels through the second material to a second end of the second material and back to the bond interface in a second amount of time. The first amount of time is substantially equal to the second amount of time. A tension is obtained in the adhesive at the bond interface.

Abstract: A vibration detection apparatus for, for example, ultrasound/AE, with Fiber Bragg Grating (FBG), is used for elastic wave detection generated by a material impact and ultrasonic defect detection. Disadvantageously, the apparatus cannot detect ultrasound and has degraded performance at variable temperatures and strains. In response, a highly sensitive, small and light vibration detection apparatus is provided. FBG reflection light is lased by using a fiber laser. The intensity of the lased reflection light from the FBG is converted into an electrical signal. Thus, the ultrasound vibration or the like is detected. A vibration detection system includes an optical amplifier 42, an optical circulator 43, and an optical coupler 45. An FBG 44 and an entry/exit port of the optical circulator are connected by an optical fiber. The optical coupler and the optical amplifier are inserted between an entry port and an exit port of the optical circulator. The entry port and the exit port are connected by an optical fiber.

Abstract: A method for determining a physical property of an object or fluid in a dynamic multi-path clutter environment comprises transmitting an RF interrogation signal to a wireless sensor physically coupled to the object or fluid (gas or liquid) in the dynamic multi-path clutter environment, wherein the wireless sensor is operable to receive the RF interrogation signal, produce a reference signal and a measurement signal, and retransmit the reference signal and the measurement signal in the dynamic multi-path clutter environment. The reference signal and measurement signal are delayed by the wireless sensor by an amount of time that may be a function of the unknown physical property. The method also comprises receiving the retransmitted reference signal and the retransmitted measurement signal and comparing them in the time domain in order to determine the unknown physical property of the object or fluid.

Abstract: A microstructure inspecting device 10 which measures a damping characteristic value of a moving portion of a microstructure includes a pressure wave generating device 1 and a pulse generating device 2 which apply an impact to the moving portion without directly contacting the microstructure, and a vibrometer 4 which measures a displacement of the moving portion for a predetermined period of time after the start of free vibration of the moving portion without contacting the moving portion. The pressure wave generating device 1 is a sound wave generating element of thermal excitation type, a piezoelectric sound wave generating element, or an electromagnetic vibration element, and is driven by a pulse signal of the pulse generating device 2.

Abstract: A method comprising preparing a baseline cement slurry comprising a cement, water, and one or more additives, placing a sample of the baseline cement slurry into a sample container having a vertical height, and measuring time of flight of energy through the sample at one or more locations along the vertical height to determine a settling property of the baseline cement slurry. A method comprising providing a settling test apparatus comprising a column having a vertical height and at least one pair of transducers positioned opposite each other with the column there between, placing a cement slurry sample within the column, and measuring time of flight of ultrasonic energy through the sample at one or more locations along the vertical height to determine a settling property of the cement slurry.

Abstract: An inline inspection system and method for calibrating an acoustic monitoring structure installed along a pipe. The system includes a pipe inspection vehicle; a microprocessor configured to attach a time stamp to a measured distance traveled by the pipe inspection vehicle; an acoustic source attached to the pipe inspection vehicle and configured to generate sound waves inside the pipe, the sound waves having predetermined frequencies and predetermined amplitudes; plural sensors disposed along the pipe and configured to record time of arrivals and intensities of the sound waves generated by the acoustic source; and a processing unit configured to communicate with the plural sensors and receive the time of arrivals, intensities and frequencies of the sound waves from the plural sensors. The processing unit calibrates the acoustic monitoring structure by calculating a distance between the acoustic source and a first sensor of the plural sensors.

Abstract: The intensity of first reflected ultrasonic waves reflected from an end of a first electrode tip is measured while the electrode tip is separated from a workpiece. The intensity of second reflected waves reflected from the end of the electrode tip is measured while the electrode tip contacts with the workpiece. Based on the above intensities, an intensity ratio (reflectance) and the fraction of the waves entering the workpiece are determined from the following equations: reflectance=(intensity of second reflected waves)/(intensity of first reflected waves) fraction of waves entering the workpiece=1?reflectance. From a predetermined correlative relationship between a contact area of a region enabling ultrasonic waves to be incident on the workpiece and the determined fraction of the entering waves, a ratio (contact area ratio) is determined between a total area of the region and a contact area of the region contacting with the workpiece.

Abstract: Methods and apparatus for determining the speed of a signal species, such as an acoustic signal, in a multilayered medium is described. The multilayer medium, generally, has a first and second layer (e.g. oil and water), whereby first and second signals are transmitted across particular distances in the medium such that a second distance differs from a first distance, and whereby the time of flight of each signal can be used in order to determine the speed of the signals species in one or both of the first and second layer. In other words, in some cases, the speed of sound can be determined in oil and/or water, or the like.

Abstract: A multi-sine vibration testing method includes coupling a vibratory excitation source and a sensor to a test structure, then providing a reference signal to the excitation source, wherein the reference signal comprises a first sinusoidal waveform having a first frequency and a second sinusoidal waveform having a second frequency different from the first frequency. The first frequency and the second frequency each sweep between a corresponding start value and a corresponding end value, and the frequency response is measured from each of the sensors while providing the reference signal.

Abstract: A device for measuring a vibration frequency of a mechanically vibrating string or rod, comprising a microwave transmitter for directing microwaves towards the vibrating string and a microwave receiver for receiving the microwaves amplitude modulated by the frequency of mechanical vibration. A member is arranged close to a vibration maximum of the vibrating string. The member is arranged on one side of the vibrating object and the microwave receiver is arranged on the other side thereof. The device is used for measuring temperature, pressure, torque, force or identity.

Abstract: A method for determining time a single transit of an acoustic wave through a test material using a calibration material having known acoustic velocity characteristics and an acoustic pitch-catch system with a signal recorder for recording a received signal as a function of time. The system includes a first configuration for transmission of acoustic shear waves and a second configuration for transmission of acoustic longitudinal waves. In the first configuration, a first acoustic zero is determined when the acoustic shear waves are applied to the calibration material. In its second configuration, a second acoustic zero is determined when the acoustic longitudinal waves are applied to the calibration material. Each configuration is coupled to a test material with the respective first and second acoustic zeroes identified on the recorder. The signal recorder determines a single transit time for the acoustic waves through the test material.