Abstract: In one example embodiment, an analysis software package implements an improved damage detection technique to identify damaged elements of a structure. The software package accesses a model and receives measured responses resulting from physical testing of the structure under initial conditions and under damaged conditions. The analysis software package may search for a set of damaged elements, wherein the searching is based on an error function that evaluates goodness-of-fit between the model and the structure under damaged conditions based on a discrepancy between a modeled response difference and a measured response difference, wherein the modeled response difference is a difference between modeled responses determined from the model configured to model initial conditions and with selected damaged elements, and the measured response difference is a difference in measured responses determined from physical testing of the structure under the initial conditions and under the damaged conditions.

Abstract: A method to measure the vibrational characteristics of an oscillating system (1) uses a control system (6, 7a, 7b, 7c). The oscillating system comprises a resonator, at least one vibration exciter and at least one sensor. The resonator is excited by the vibration exciter, and the motion of the resonator is measured by the sensor. The control system uses the sensor to control the motion of the resonator by the vibration exciter. The motion of the resonator is a superposition of at least two harmonic motions, and the control system comprises at least two subcontrollers (7a, 7b, 7c). Each harmonic motion is controlled independently by one of the subcontrollers. The harmonic motions are controlled by the subcontrollers simultaneously. A corresponding device is also disclosed.

Abstract: There is provided a system and method for the measurements of viscoelastic properties of a soft sample in which the system incorporates a sample holder that has a membrane with a flexural rigidity that is less than the flexural rigidity of the main body and allowing vibration of the membrane-sample vibration unit in response to a vibration excitation to create resonance vibration modes that are detected to derive the viscoelastic properties.

Abstract: Shear waves are detected with ultrasound. The detection of the shear wave is constrained using prior measurements in a more controlled environment (e.g., less noise). For example, shear waves measured in a phantom are used to constrain the detection of shear waves in a patient to avoid false positive detections.

Abstract: A golf club set includes a plurality of golf clubs having different loft angles. The plurality of golf clubs have the same lie angle. Each loft angle difference between two golf clubs that are adjacent in a loft angle order is the same. Each club length difference between two golf clubs that are adjacent in the loft angle order is 0.125 inches (3.175 mm) (inclusive) to 0.375 inches (9.525 mm) (inclusive). A loft angle of a golf club having a minimum frequency is smaller than a loft angle of a golf club having a maximum frequency. A difference between the minimum frequency and the maximum frequency is not less than 40 cpm.

Abstract: An anchor bolt diagnosing system includes a vibration sensing clip that clips an anchor bolt, and senses a vibration power of the anchor bolt, a blow sensing hammer that gives a blow to the anchor bolt clipped by the vibration sensing clip, and senses blow strength, and a diagnoser that obtains the vibration power and the blow strength output from the vibration sensing clip and the blow sensing hammer, and diagnoses soundness of the anchor bolt in accordance with whether a ratio of the vibration power to the blow strength is higher than a predetermined value.

Abstract: A method for monitoring the operation of a gas turbine is provided, in which component vibrations are detected during the operation of the gas turbine by an acceleration sensor arranged on the component, a plurality of signal sections being determined by a plurality of frequency bands fb from the signal forwarded and processed by the acceleration sensor. To avoid an unnecessary shutdown of the gas turbine to perform an inspection which subsequently proves unnecessary, thereby increasing the availability of the gas turbine, a total vibration period is determined by adding together the vibration periods of signal sections during which the amplitudes of the signal sections concerned are greater than a frequency band-specific threshold.

Abstract: A vibration visualizer comprising an optical member including a fixed section to be fixed to a measurement object; and a movable section movably supported by the fixed section such that a first positional relationship between the fixed section and the movable section is changed by application of an acceleration to the fixed section in a predetermined direction. The optical member changes a reflection intensity of light or electromagnetic wave reflected in a retroreflection direction according to a change of the first positional relationship. The first positional relationship in a stationary state where the acceleration is not applied to the fixed section and the first positional relationship is maintained constant, is different from the first positional relationship most suitable for retroreflection.

Abstract: Provided is an ultrasonic displacement sensor that more accurately identifies a plurality of models on a conveyance line on which a plurality of types of workpieces having different specifications coexists, in particular, on a conveyance line of cylinder blocks in a manufacturing facility of engines for automobiles, to thereby improve reliability.

Abstract: In an optical device, a ring-resonator modulator, having an adjustable resonance (center) wavelength, receives an optical signal that includes a carrier wavelength from an input-output optical waveguide. Then, a monitoring mechanism monitors a performance metric (such as an average power or a signal swing) of a monitor optical signal from the ring-resonator modulator. Moreover, control logic in the optical device adjusts the resonance wavelength based on the monitored performance metric so that the resonance wavelength is locked to the carrier wavelength. In particular, the control logic may apply a change to an adjustment signal that is provided to the ring-resonator modulator. If the change increases the performance metric, the control logic may continue to modify the resonance wavelength. Otherwise, the control logic may modify the resonance wavelength by applying one or more changes, having an opposite sign to the change, to the adjustment signal.

Abstract: A method of processing material includes positioning a transmitter to engage an ore sample with a sub-millisecond electromagnetic pulse, the ore sample including a conductive mineral particle and a volume of a gangue, specifying a characteristic of the electromagnetic pulse based on a desired energy deposition for the conductive mineral particle using a processing circuit, and selectively depositing energy with the electromagnetic pulse to at least one of melt and vaporize the conductive mineral particle by controlling the transmitter with the processing circuit.

Abstract: An apparatus for bolt inspection are presented. The bolt has a cylindrical threaded surface delimited by a pair of end faces that are opposite to each other. An ultrasonic transducer device contacts one of the pair of end faces for performing a scan operation. A guide structure is engaged with the bolt that guides a motion of the ultrasonic transducer device such that only a portion of a transducer contact surface contacts the one of the pair of end faces during the scan operation. The guide structure delimits a radial extent of the motion of the ultrasonic transducer device during the scan operation.

Abstract: Systems and methods for implementation of the heterodyne effect in structural health monitoring (SHM) systems are provided. A system or method can include propagating a first signal with a first frequency and a second signal with a second frequency through a subject structure, and analyzing the output response to determine if a third frequency has been created, according to the heterodyne effect.

Abstract: A method for determining the temperature of an aggressive and/or abrasive gas is described using an acoustic transmitter and an acoustic receiver. The transmitter emits an acoustic signal with varying frequencies and the receiver extracts from the acoustic input signal a frequency of the maximum. Based on this the frequency of this maximum the temperature of the gas between transmitter and receiver is calculated.

Abstract: Provided is a safety inspection apparatus for a bridge using an expansion joint with a load cell capable of inspecting safety of a bridge and checking an overweight of a traveling vehicle by including a load cell installed at a lower portion of an expansion joint installed between upper plates of a bridge to measure a load of a traveling vehicle, and a measuring device installed on the bridge to measure behavior of the bridge, determining a total weight of a vehicle to manage an operation of an overweight vehicle which hinders safety of a structure and road pavement, measuring and storing weight data of a vehicle passing over the bridge as behavior data of the bridge in real time, and determining performance, a degree of deterioration, and a damaged position of the bridge without a separate safety inspection by analyzing the data over the long term.

Abstract: An apparatus for measuring noise includes: a signal generator configured to input an input signal having an excitation frequency to an audio device; and a controller configured to measure rattle noise from a sound pressure signal generated in response to the input signal. The controller measures the rattle noise by comparing a frequency component of the sound pressure signal with a masking curve corresponding to the excitation frequency.

Abstract: An automatic wiper control system for a vehicle window determines the presence of rainfall based on window vibrations. During a vehicle driving cycle, a controller measures the window vibrations with an accelerometer attached to the window. The controller calculates a psycho-acoustic metric based on the measured vibrations, wherein the metric can be comprised of Articulation Index, Sharpness, or Roughness. The calculated metric is compared to a threshold indicative of rain impacting the window. The wiper system is activated according to a result of the comparison.

Abstract: A vibrator element has a detection arm that performs a drive vibration in a Z-axis direction, and performs a detection vibration in an X-axis direction when an angular velocity is applied thereto The vibrator element also has first, second, third, and fourth electrode portions and first, second, third, and fourth ground electrode portions provided on a detection arm. Further, a signal generated between the first electrode portion and the first ground electrode portion and a signal generated between the second electrode portion and the second ground electrode portion are in opposite phase in a drive vibration and in phase in a detection vibration. Furthermore, a signal generated between the third electrode portion and the third ground electrode portion and a signal generated between the fourth electrode portion and the fourth ground electrode portion are in opposite phase in the drive vibration and in phase in the detection vibration.

Abstract: 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).

Abstract: The invention relates to a method for determining the radius of a pile in the ground that can be produced by means of a jet-grouting process, comprising the steps of: introducing at least one level-measuring stick into the ground; sinking a jet-grouting tool (3) down to a defined distance from the level-measuring stick (4), the distance being less than a maximum range R of the grouting jet; pulling the jet-grouting tool (3) while performing a rotating or swivelling motion with the grouting jet activated, thereby producing vibrations as the grouting jet passes the level-measuring stick (4); and recording a signal representative of the vibrations at the at least one level-measuring stick (4) by means of a sensor (5) that is fastened to the level-measuring stick (4). The invention also relates to a corresponding arrangement (2) for determining the radius of a pile in the ground that can be produced by means of a jet-grouting process.

Abstract: A sensor array comprises resonant sensors and porous receptor materials arranged on the resonant sensors to absorb or adsorb one or more analytes. The average pore size of the porous receptor materials on the sensors increases systematically from one sensor to the next in the array. At least one detector is arranged to detect responses of the resonant sensors when the array is exposed to a sample potentially containing one or more of the analytes. In some embodiments, a processor is programmed to determine from the sensor responses the presence, amount or relative concentration of target molecules in the sample.

Abstract: A method in a wireless communication terminal includes receiving configuration signaling for transmitting on a first set of radio resources wherein transmitting only on the first set of radio resources leads to a time-domain periodic repetitive pattern of transmissions from the terminal in a transmission interval that causes interference to a companion device communicably coupled to the wireless communication terminal. The terminals selects a second set of radio resources for transmitting on in the transmission interval such that transmissions on a combination of the second set of radio resources and the first set of radio resources does not lead to a periodic repetitive pattern of transmissions from the terminal in the transmission interval.

Abstract: In a QCM sensor and a method of manufacturing the same, the QCM sensor includes: a quartz plate; and an electrode provided on one and the other principal surfaces of the quartz plate, in which the electrode is provided with a pattern having a contour line in a planar view of the electrode.

Abstract: A mechanical force measurement system is for measuring a force onto an object. The measurement system includes a sound wave generator which is adapted to generate a solid borne sound wave signal within the object. The system further includes a first sound wave receiver which receives a first solid borne sound wave signal based on the solid borne sound wave signal generated within the object by the sound wave generator. In order to compare a phase of the generated solid borne sound wave signal and a phase of the first received solid borne sound wave signal, and to generate a comparison signal based thereon. The system also includes a comparator unit. An evaluation unit of the system determines the mechanical force based on a data base and the comparison signal. The data base has stored a relation of a mechanical force and a comparison.

Abstract: A method and an apparatus for bolt inspection are presented. The bolt has a cylindrical threaded surface delimited by a pair of end faces that are opposite to each other. An ultrasonic transducer device contacts one of the pair of end faces for performing a scan operation. A guide structure is engaged with the bolt that guides a motion of the ultrasonic transducer device such that only a portion of a transducer contact surface contacts the one of the pair of end faces during the scan operation. The guide structure delimits a radial extent of the motion of the ultrasonic transducer device during the scan operation.

Abstract: The invention relates to a measurement system including a network of nanoelectromechanical system (NEMS) resonators, characterized in that: each one of said resonators includes: an electrostatic activation device capable of generating a vibration of a beam exposed to said excitation signal, at least one piezoresistive stress gauge made of a doped semiconducting material, extending from the beam so as to detect a movement of said beam, the variation in the electrical resistance of said at least one gauge supplying an output signal; said network includes at least two groups of resonators, each group including at least two resonators having an identical empty resonance frequency, each group of resonators having an empty resonance frequency different from that of each other group; the resonators forming each group are connected in parallel; the groups of resonators forming said network are connected in parallel; said system includes a reading device designed to supply an excitation signal at the network input and

Abstract: A method is disclosed for testing for delamination of a first composite component from a second composite component a composite material. The method comprises coupling a broad-band actuator to the composite material and connecting sweeping frequencies to the broad-band actuator for vibrating the composite material. An acoustic sensor is coupled to the composite material for measuring a resonant frequency curve of the vibrating composite material. The measured resonant frequency curve of the vibrating composite material is compared with a reference resonant frequency curve. A delaminated composite material produces a change in the measured resonant frequency curve relative to the reference resonant frequency curve. The method is suitable for detecting delamination in fuel cells as well as ceramic body armor.

Abstract: Provided is a wireless measuring system based on a cochlea principle for acquiring a dynamic response of a constructional structure and capable of monitoring and controlling health of the constructional structure in real time by acquiring the dynamic response of the constructional structure in which irregular random vibrations occur, effectively compressing the acquired data, wirelessly transmitting a signal, and analyzing the transmitted signal.

Abstract: Improved active vibration control (AVC) devices, systems, and related methods are provided herein. An AVC device includes a controller adapted to receive real-time aircraft information and adjust at least one control parameter as a function of the real-time aircraft information is provided. An AVC device is adapted to detect changes in real-time aircraft information, as the aircraft moves from a steady state to transient performance, low and high air speeds, or vice versa. An AVC system (e.g., AVCS) includes one or more sensors, one or more actuators, and a controller adapted to receive real-time aircraft information and adjust at least one control parameter. In some aspects, a method of controlling vibration within an aircraft includes receiving vibration information from at least one sensor, receiving real-time aircraft information from an avionics system, adjusting at least one control parameter used in a control algorithm, and generating a force command.

Abstract: The present disclosure provides an apparatus for characterizing mechanical properties of a sample. The apparatus comprises a structure for supporting the sample and applying a first pressure in a first direction to the sample and an actuator for modulating the first pressure. The apparatus also comprises a pressure applicator containing a liquid and arranged to apply a second pressure to the sample in a second direction that is transversal to the first direction. Further, the apparatus comprises a pore pressure applicator arranged to apply a flow of a fluid through a porous sample such that a pore pressure is applied to the porous sample. In addition, the apparatus comprises a sensor for sensing a change in the sample in response to a change in a pressure experienced by the sample.

Abstract: Disclosed is a structure analyzing device and a structure analyzing method which can analyze a state change of a structure, which is caused before the structure is destroyed, such as a state change of degradation of the structure or the like. A structure analyzing device (10) includes a vibration detecting unit (11) which detects a vibration of a structure, and an analysis unit (12) which analyzes an output signal of the vibration detecting unit (11). The analysis unit (12) analyzes a state change of the structure by comparing a value of resonant sharpness Q, which is measured by use of the following formula (1) in a state existing when carrying out analysis, with a value of resonant sharpness Q which is measured by use of the following formula (1) in a standard state.

Abstract: A sensing device is provided that has satisfactory sensing accuracy when a crystal unit where an excitation electrode is formed on both upper and lower surfaces of a piezoelectric piece is used to sense a sensing object. Adsorption regions are arranged in two places so as to intersect a direction of flow of a fluid, thus each of the adsorption regions senses the sensing object and reference regions are individually provided in these adsorption regions. A difference ?f1 between the oscillation frequencies of the regions and a difference ?f2 between the oscillation frequencies of the regions are added, and based on the result of the addition, whether the sensing object is present or not and its concentration are detected.

Abstract: Improved active vibration control (AVC) devices (20), systems, and related methods are provided herein. An AVC device (20) includes a controller (24) adapted to receive real-time aircraft information and adjust at least one control parameter as a function of the real-time aircraft information is provided. An AVC device is adapted to detect changes in real-time aircraft information, as the aircraft moves from a steady state to transient performance, low and high air speeds, or vice versa. An AVC system (e.g., AVCS) includes one or more sensors (22), one or more actuators (26), and a controller (24) adapted to receive real-time aircraft information and adjust at least one control parameter. In some aspects, a method of controlling vibration within an aircraft includes receiving vibration information from at least one sensor (22), receiving real-time aircraft information from an avionics system (40), adjusting at least one control parameter used in a control algorithm, and generating a force command.

Abstract: A heat trace system heats (or maintains the temperature of) vessels of a piping system. Heat trace cables are connected to power control devices in respective wireless modules such that when the power control device in a wireless module is on, the heat trace cable connected to that wireless module conducts current, and thereby heats the vessel contacting the heat trace cable. The wireless module receives control commands for controlling its power control device wirelessly from the main power distribution and control system via a wireless communication network. A wireless module can include a sensor, where the wireless module report backs conditions sensed by the sensor to the main power distribution and control system via the wireless network.

Abstract: Method, apparatus, and computer program product for providing a cause of a scent and/or sound detected during operation of a vehicle are provided. In the event a vehicle operator hears a sound or smells a scent while operating a vehicle, a microphone can sample the sound and/or an electronic nose can sample the scent. A sound and/or scent profile is generated from the sampled sound and/or sampled scent. The generated sound and/or scent profile are compared to known sound and/or scent profiles stored in a data structure. In the event the generated sound and/or scent profile matches a known sound and/or scent profile, the data structure is checked for correspondences between the matched, known sound and/or scent profile and a cause of the sound and/or scent. In the event a correspondence to a cause exists, then the cause is output to a user to identify the cause of the sound and/or scent.

Abstract: An in-medium monitoring system for monitoring material carried within a pipe. The system includes an acoustic device installed within the pipe that generates voltage signals indicative of changes in the material, such as flow rate or leaks, a hardware unit that includes a detector module and a communication module, a switch for switching the voltage signals to and communication signals from the hardware unit. The hardware unit and a power source are attached to the pipe. The acoustic device may be detector or a sensor. The communication module may communicate date through the sensor in the medium or outside of the pipe to a fixed network. The hardware unit may include a log detection amplifier for generating an amplified pulsed output signal without voltage gain and without significantly adding noise.

Abstract: An assertion assessment system is presented. An assertion object that represents a relationship between an assertion and an information source can be bound to a quality measure as an indication of the quality of the assertion object. The assertion assessment system enables different recipients of assertion objects that are linked to information sources to assess assertion quality of the assertion objects. The assertion assessment system manages and tracks these assessments of the assertion objects and provides useful indications to the recipients. Thus, workers who come upon an assertion can make a judgment on the quality of the assertion based on assessment made by other workers, without going through the information source that supports the assertion.

Abstract: A label-free biochemical assay, in which label-free interrogation of a target-receptor layer is performed while the target-receptor layer is subjected to a relatively strong flow of an analyte-containing fluid. The volumetric flow rate for the assay is selected based on calibration data corresponding to the target substance, which advantageously results in fewer and/or smaller false-positive signals corresponding to non-target substances compared to those produced with the fluid being stationary. In various embodiments, the label-free interrogation method can be electro-mechanical and/or optical.

Abstract: Heat trace system for heating vessels of a piping system comprises a main control system, a plurality of heat trace elements, and a plurality of wireless modules. Each heat trace element is adjacent to one of the vessels of the piping system and connected to an electrical power source of the main control system 16. Each of the wireless modules: (a) is connected to and powered by an associated heat trace element; (b) comprises an energy storage device connected to the associated heat trace element for storing energy from the associated heat trace element to power the wireless module; and (c) comprises an RF module for communicating wirelessly with the main control system via a wireless communication network. The stored energy in the energy storage device can be used to power components of the wireless module, even when no current is flowing in the heat trace element to which the wireless module is connected.

Abstract: An aircraft ice protection system (10) comprises an ice protection device (21), an onboard power source (30), a supply line (31) from the power source (30) to the device (21), a controller (41) which controls the line (31), and an optimizer (50) which conveys operation-optimizing instructions (51) to the controller (41). An ice detector (60) provides an input (70) to the optimizer (50) and this ice-condition input (70) is used to generate the operation-optimizing instructions (51).

Abstract: In accordance with embodiments of the present disclosure, systems and methods for determining a dynamic effective elastic modulus of a composite slickline or wireline cable are provided. A system for estimating the effective elastic modulus (or change thereof) may include a sensing head assembly, a vibration generator, a pair of pulleys, and an optical-based signal processing assembly. The system may detect a resonant frequency of a section of the composite cable held between the two pulleys and estimate the effective elastic modulus based on the detected resonant frequency variation. Adjustments for weight and length of the cable extending into the wellbore may be made as well to determine the dynamic elastic modulus of the cable. The opto-mechanical integrated system described below may enable real-time elastic modulus determination.

Abstract: A system for on-line detection of incipient cracks in turbine blades to serve as early warning system for turbine blade failure. The system of non-intrusive detection of turbine blade condition of the invention is simple and cost effective and would enable assessing the health of the turbine blade during plant operation, which is extremely important for the safe operation of the turbine in an operating power plant. The present method and system of identifying the presence of modulated blade passing frequency (BPF) for blade vibration that is not correlatable to the change in the operating condition and would thus be indicative of presence of cracked blades with incipient cracking. It is capable for verifying the Campbell diagram and ascertain the margin available between the natural frequency of the blade/stage and the steam excitation frequencies/engine orders.

Abstract: A method implemented using a controller based device includes receiving a measured electrical signal from an electrical device of an electromechanical device and receiving a measured vibration signal from a mechanical device of the electromechanical device, coupled to the electrical device. The method further includes determining a first signal signature based on the measured electrical signal and determining a second signal signature based on the measured vibration signal. The method also includes determining a diagnostic parameter based on the first signal signature and the second signal signature and determining a fault in the mechanical device based on the diagnostic parameter.

Abstract: Apparatuses and methods are disclosed for determining whether a structure of bonded layers includes locations where the layers are weakly bonded. Embodiments include evaluating the frequency response of the structure in response to vibrational inputs. Alternate embodiments include evaluating the non-linear response of the structure using a modal analysis. Further embodiments include obtaining the vibrational information with an accelerometer contacting the structure, while additional embodiments include exciting the structure with an impact force, which may be applied at multiple locations on the structure's surface. Still further embodiments include performing a MAC, COMAC, and/or FRF analysis. Still other embodiments include varying the amplitude of the input vibration. Additional embodiments locate the areas of weakened bonding. Still other embodiments include methods and apparatuses for simulating a laminated structure with defective bonding, such as kiss bonding.

Abstract: The invention relates to vibrating micro-systems, and notably but not exclusively to pressure, acceleration, or angular speed micro-sensors with a resonator in an evacuated cavity. The resonator (10) with a vibrating element is placed in an oscillating circuit controlled by a closed-loop control, the oscillating circuit supplying an oscillating signal y(t) at a resonance frequency Fp representing the measurement of a physical quantity. The resonance frequency is calculated by counting pulses over a time window. The sensor furthermore comprises means for calculating a continuity parameter Pc representing the variations in the result of the calculation of the resonance frequency over the course of the successive time windows, and means for comparing the parameter Pc with a threshold in order to deduce from this information on the degradation of the precision of the sensor.

Abstract: A method for determining the composition of fluids flowing through pipes from noninvasive measurements of acoustic properties of the fluid is described. The method includes exciting a first transducer located on the external surface of the pipe through which the fluid under investigation is flowing, to generate an ultrasound chirp signal, as opposed to conventional pulses. The chirp signal is received by a second transducer disposed on the external surface of the pipe opposing the location of the first transducer, from which the transit time through the fluid is determined and the sound speed of the ultrasound in the fluid is calculated. The composition of a fluid is calculated from the sound speed therein. The fluid density may also be derived from measurements of sound attenuation. Several signal processing approaches are described for extracting the transit time information from the data with the effects of the pipe wall having been subtracted.

Abstract: Surface modifications to sensors in an array give the sensors different functionalities for adsorbing or binding molecules. A first sensor in the array includes a first resonating member having a first surface comprising a receptor material coated over a first underlying material. A second sensor includes a second resonating member having a second surface comprising the receptor material coated over a second underlying material that is different than the first underlying material. The first underlying material, the second underlying material, and the receptor material are selected such that the first resonating member, having a combination of the receptor material and the first underlying material, has a different ability to adsorb or bind a mass of one or more analytes than does the second resonating member having a combination of the receptor material with the second underlying material. Methods for fabricating sensors with surface modifications are also provided.

Abstract: A method of measuring a crystallographic orientation of an object using an ultrasonic transducer and a detector array including a plurality of ultrasonic detectors includes: determining a minimum distance between the transducer and the detector of the detector array closest to the transducer; placing the transducer and the detector array in contact with a surface of the object such that the transducer and the detector of the detector array closest to the transducer are separated by at least the minimum distance; using the transducer to generate an ultrasonic surface wave pulse in the surface of the object, the ultrasonic surface wave pulse having a pulse duration and including a longitudinal surface wave and a Rayleigh wave; and measuring a time of flight of a surface wave generated by the transducer between the transducer and each detector of the array to determine the crystallographic orientation of the object.

Abstract: The shape or position of an object is estimated using a device comprising one or more transmitters and one or more receivers, forming a set of at least two transmitter-receiver combinations. Signals are transmitted from the transmitters, through air, to the object. They are reflected by the object and received by the receivers. A subset of the transmitter-receiver combinations which give rise to a received signal meeting a predetermined clarity criterion is determined. The positions of points on the object are estimated using substantially only signals from the subset of combinations.

Abstract: A method is provided for identifying resonant frequency vibration events in an assembly of rotating blades mounted on a rotor. A plurality of circumferentially spaced stationary timing probes associated with the blades detect the times at which the blades pass the respective probes. The method includes the steps of: obtaining blade timings detected by the probes, determining, for successive rotations of the assembly, respective correlation factors for one or more of the blades, each correlation factor quantifying the degree of correlation between the blade timings detected by the probes for a particular blade on a particular rotation and the blade timings detected by the probes for that blade on the previous rotation and identifying a resonant vibration event when the one or more correlation factors cross a predetermined threshold.