Abstract: The invention relates to methods, kits and systems for determining an analyte in a liquid sample as well as the use thereof for concentration analysis and screening purposes. In one method, a specific binding partner to the analyte is permitted to compete with a conjugate containing the analyte or an analyte analogue for the binding to free analyte. The conjugate also contains a component that specifically binds to a solid support so that reacted and unreacted conjugate are bound thereto when the reaction solution is contacted with the solid support. The amount of analyte is then determined by measuring by a label-free mass-detection technique, such as surface plasmon resonance, the amount of binding partner immobilized on the solid support via the reacted conjugate. This is made possible by the binding partner having a considerably greater mass than the conjugate. Variants of this method are also disclosed.

Abstract: A paper quality determining sensor and a faulty paper sorting device capable of detecting reaction forces of paper sheets themselves which vary according to paper quality using a plurality of rollers so as to detect the stiffness (rigidity) of paper sheets accurately without being affected by thicknesses of the paper sheets.

Abstract: The invention is a method for monitoring an environment by evaluating an infrasonic signal obtained from said environment. The method includes averaging said infrasonic signal (Vinfra) to provide an averaged infrasonic signal (Vav), mapping said averaged infrasonic signal (Vav) according to a function to provide an infrasonic noise signal (Vnoise); averaging said infrasonic noise signal (Vnoise) to provide an averaged infrasonic noise signal (Vav noise); offsetting said averaged infrasonic noise signal (Vav noise) with an offset value to provide an infrasonic level signal (Vlimit); comparing said infrasonic level signal (Vlimit) with said averaged infrasonic signal (Vav); and generating a trigger signal (30) if said averaged infrasonic signal (Vav) is greater than said infrasonic level signal (Vlimit).

Abstract: Methods and apparatus for simultaneous or sequential, rapid analysis of multiple samples by photoacoustic spectroscopy are disclosed. Particularly, a photoacoustic spectroscopy sample array vessel including a vessel body having multiple sample cells connected thereto is disclosed. At least one acoustic detector is acoustically positioned near the sample cells. Methods for analyzing the multiple samples in the sample array vessels using photoacoustic spectroscopy are provided.

Abstract: A method of detecting a convexity present on a surface of a belt-shaped member (belt) or a roll-shaped member (roller), includes frictionizing (abrading) a surface of the member with a plate, and detecting at least one of (1) a vibration generated on the plate or (2) a change of pressure applied to the plate, to detect the convexity on the surface of the member.

Abstract: The invention is an apparatus that measures dirt density on steel plates, characterized by including a pulsed laser that impinges on the inspected plate, and a microphone that detects the sound produced by the sudden ablation of the dirt, the amplitude of the microphone signal being the measure of the dirt on the plate. The microphone is connected to an electronic signal processing system, which is a computer or a programmed digital processor that determines the average value and standard deviation of the signal over the number of hits specified by the operator.

Abstract: Internal combustion engines and electric motors in motor vehicles generate, at all operating points, airborne emissions and solid-borne emissions, which are superimposed in the interior of the vehicle and perceived as engine noise by the occupants. To differentiate quantitatively between airborne and solid-borne portions of engine noise, sound measurement are made in the vehicle interior and engine compartment both with air and when the engine compartment is flooded with a gas having different acoustic characteristics than air. From analysis of the two measurements, the solid-borne portion and the airborne portion of the engine noise can be determined with a high degree of precision.

Abstract: A device and a method for the non-destructive testing of passive components by applying an electrical test signal to passive components and an acoustic emission is measured by a microphone and, the measured signal is applied to an evaluation unit.

Abstract: The invention relates to a diagnostic system and method, especially for a valve (2) that can be actuated by a positioner (9) via a drive (6). The system utilizes a sensor (12) for recording structure-related sound and has a device (14) for evaluating a recorded measurement signal (13). A spectral region greater than 50 kHz is evaluated for conducting fault recognition. A fault indication signal is generated if the intensity of the measurement signal in this spectral region exceeds a defined threshold value. The sound caused by cavitation is primarily evaluated for conducting fault recognition.

Abstract: The present invention is for a system (11) or method for conditioned based monitoring of an assembly (12). The system (11) comprises a sensor (13) placed in proximity to an assembly (12). The sensor (13) generates a signal indicative of the amplitude and frequency of the ultrasonic output of the assembly (12). A processor (14) in communication with the sensor (13) receives the signal from the sensor (13) and generates spectral data representative of the ultrasound emanating from the assembly. A database (15) comprises data representative of operating parameters of the assembly (12). The processor (15) compares the spectral data to the operating parameters and generates a signal indication of the condition of the assembly (12).

Abstract: The present invention relates to a method for acoustic emission analysis of a granular composition comprising a biologically active compound, said method comprising colliding the granular composition with at least one surface transmitting low frequency vibrations, recording low frequency vibration data in range of 10 Hz to less than 50 kHz, arising from the collision, with at least one vibration detector and subjecting the recorded low frequency vibration data to computerized data processing.

Abstract: A method is provided for measuring the residual stress in metals. The method includes the steps of drilling one or more holes in a metal workpiece to a preselected depth and mounting one or more acoustic sensors on the metal workpiece and connecting the sensors to an electronic detecting and recording device. A liquid metal capable of penetrating into the metal workpiece placed at the bottom of the hole or holes. A recording is made over a period of time (typically within about two hours) of the magnitude and number of noise events which occur as the liquid metal penetrates into the metal workpiece. The magnitude and number of noise events are then correlated to the internal stress in the region of the workpiece at the bottom of the hole.

Abstract: An apparatus and method for monitoring and reporting downhole bit failure. Sensors are located on a sub assembly (which is separate from the drill bit itself but located above it on the drill string). Data from the sensors (preferably accelerometers) are collected in blocks, then analyzed in the frequency domain. The frequency domain is divided into multiple bands, and the signal power in each band is compared to that of another band to produce a ratio of powers. When a bit is operating at normal condition, most of the spectral energy of the bit vibration is found in the lowest frequency band. As a bearing starts to fail, it produces a greater level of vibration in the higher frequency bands. This change in ratios is used to determine probable bit failure. Bit failure can be indicated by a given ratio surpassing a given threshold, or by monitoring the standard deviation of the frequency ratios. When the standard deviation exceeds a certain value, a failure is indicated.

Abstract: A crack detection method capable of detecting cracks on a scale of about 5 &mgr;m or greater, useful for detecting cracks in sol-gel tubes. A signal is transmitted from a source to a body in which cracking may occur. The signal is reflected back to a sensor. An output voltage from the sensor is measured which is proportional to a signal characteristic change between the transmitted and received signals. Signal characteristics such as frequency, phase, and amplitude may be monitored. The signal characteristic change may result from one or more mechanisms selected from the group consisting of microscopic motion of the body, media transition and fluid movement.

Abstract: An apparatus for detecting blockage of a porous medium of an air filter utilized to filter air within a forced air stream contained within an enclosure. The air filter extends in a direction transverse to a direction of the forced air stream. The detection is accomplished with an opening in the porous medium of a greater dimension than provided by the porous medium. The opening is defined by the porous medium of the air filter and extends through the porous medium through which airflow from the forced air stream passes. A flexible member is provided which is positioned within the air flow from the forced air stream which passes through the opening and received by the flexible member causing the flexible member to vibrate and emit an audible sound in response to the air flow.

Abstract: A pipe 16 having a produced fluid 18 (liquid an/or gas) and at least two acoustic pressure sensors 20-24, is provided with a cylindrical sleeve 30 attached to the pipe 16 at two locations around a sensing region where the sensors 20-24 are located, the sleeve forming a closed cavity 32 filled with a fluid (or material) having an acoustic impedance (&rgr;c2) that is much less than the acoustic impedance (&rgr;c1) of the produced fluid 18 in the pipe 16 (i.e., &rgr;c2<<&rgr;c1), which causes the sleeve 20 to isolate the acoustic sensors 20,22,24 from being affected by acoustic properties of the cavity 32 and the acoustic properties outside the pipe 16. For most effective acoustic, the cavity 32 may be evacuated.

Abstract: A method of analyzing the condition of a surface such as that of a rail, includes: causing a vehicle to travel along the rail, the vehicle having a first wheel and a second wheel which are in contact with the rail; detecting through the first wheel sound signals propagating along the rail from the second wheel as a consequence of the second wheel traveling along the rail; and analyzing the characteristic features of these sound signals to determine the condition of the rail. This method avoids the use of an ultrasonic sound generator, and can be fitted to standard freight and/or passenger trains to provide a constantly updated picture of the condition of the rails in a railway system.

Abstract: An apparatus and method for determining at least one boil phase of a liquid is provided. The boil phase is determined from an acoustic signal generated by the liquid during heating, the acoustic signal is measured by an acoustic sensor. The apparatus comprises at least one filter connected to the acoustic sensor. The at least one filter receives and filters the acoustic signal to eliminate excess variation and to eliminate high frequency noise from the acoustic signal producing a filtered acoustic signal. At least one derivative estimation filter is also provided and is connected to the at least one filter. The at least one derivative estimation filter estimates at least one derivative of the filtered acoustic signal. A processor is provided and is connected to the at least one filter and the at least one derivative estimation filter. The processor identifies the at least one boil phase of the liquid using at least the filtered acoustic signal and at least one derivative of the filtered acoustic signal.

Abstract: A weather forecasting apparatus, which is capable of accurately forecasting local atmospheric phenomena, has a vibration sensor attached to a tree for measuring an arboreal sound propagated through the tree. A voltage outputted from the vibration sensor depending on the measured arboreal sound is sent via an arboreal sound observing device to a data processing device. The data processing device includes a forecasting processor which determines the start or end of a rainfall based on the magnitude of the voltage, i.e., a sound pressure level corresponding to the magnitude of the sound pressure of the arboreal sound. When the sound pressure level rises, the forecasting processor determines the end of a rainfall, and when the sound pressure level drops, the forecasting processor determines the start of a rainfall. There is also disclosed a snowfall forecasting apparatus capable of accurately forecasting a local snowfall.

Abstract: Apparatus and method for monitoring acoustic emission signals in machinery that processes solid material such as aspirin to detect rubbing conditions. The apparatus includes an acoustic signal processing system having a computer, an acoustic signal processing program capable of configuring the computer as a filter, and a rubbing signal identifier that configures the computer to set filter conditions for the filter and to detect a rubbing signal. The filter conditions remove some operating noise having a hit rate higher than the operating rate of the rotating part of the machinery by excluding amplitudes less than a front end filter threshold amplitude and durations less than a front end filter duration. The rubbing signals are detected according to the criteria: intensity greater than a predetermined intensity, acoustic emission activity greater than the operating rate of the rotating part and signal length greater than a predetermined signal length.

Abstract: A sensor array for nondestructively monitoring a structure to detect a critical event. The sensor array includes a plurality of discrete sensor nodes, each of the discrete sensor nodes producing an electrical signal in response to a structural event. In the preferred embodiment, the sensor nodes include a plurality of piezoceramic fibers arranged in a planar array in which the fibers are aligned substantially parallel to each other, each of the fibers having a plurality of polarized regions that are substantially oriented according to their polarity in either a series, parallel, or combined arrangement of series and parallel orientations, and an electrical interface connecting the plurality of polarized regions of each fiber in series with one another. A signal adder receives and combines the electrical signals from each of the discrete sensor nodes to form a single sensor array output signal.

Abstract: Disclosed is a noise source visualizing system used in a wind tunnel test to measure generated sounds, the system comprising an acoustic mirror for converging sound waves of sounds generated on a surface of a vehicle during a wind tunnel test; a microphone measuring the converged sound waves; an image-photographing unit photographing locations on the vehicle at which the sounds are generated; a first display unit displaying the sounds measured by the microphone as colors that vary according to characteristics of the sounds; a movable traverse to which the acoustic mirror is connected for enabling the acoustic mirror to collect the sounds; a workstation for analyzing the converged sound waves measured by the microphone, the images photographed by the image-photographing unit, and the signals displayed through first display unit; and a second display unit overlapping then displaying image signals photographed by the image-photographing unit and the colors displayed on the first display unit.

Abstract: The invented apparatus includes at least one acoustic sensor, a mapping unit, a controller, and a transducer. The sensor is coupled to an object to be inspected for damage, and generates a sensed signal based on acoustic signal occurring in the object under an applied load, which signal may or may not be the sound of damage occurring in the object. The mapping unit is coupled to receive the sensed signal from the sensor, and generates damage data based thereon. The controller is coupled to receive the damage data from the mapping unit. Initially, the apparatus is in a passive mode in which the apparatus senses an acoustic signal from the object. If the damage data indicates that the object has incurred possible damage in the passive mode, the controller switches to active mode and outputs induced signal data. The transducer is coupled to the object as well as the controller, and induces acoustic signal in the object, based on the induced signal data.

Abstract: A high-speed bearing vibrational analysis system for testing a bearing includes a bearing holding member to accommodate a shaft and the bearing. The bearing holding member is adapted to rotate the bearing at high-speeds. The shaft is inserted into an accommodation portion of the bearing holding member. A vibration sensor is in contact with the bearing to detect vibrations of the bearing, while it is rotated at high speeds, and to transmit data for analysis. A computer system is provided for executing a software program that receives and analyzes the data from the vibration sensor.

Abstract: A transmitter of audible sound waves is disposed at one end of a communicating hole of a cast molded article such as a cylinder block, and a receiver of audible sound waves is disposed at the other end of the communicating hole. The quality of the communicating hole is determined by receiving audible sound waves from a transmitter which have passed through the communicating hole and computing and processing a frequency spectrum of the received audible sound waves based on a reference frequency spectrum.

Abstract: A method and an apparatus for detecting and measuring cracks in plate-like structures using acoustic emission technique are disclosed. A false aperture transducer is designed to provide a criterion for filtering out extraneous noise in the acoustic emission signal based on modal analysis by computing the ratio of the high-frequency peak amplitude to low-frequency peak amplitude of the signal. A calibration curve correlating crack depth to the amplitude ratio can be obtained by simulating crack growth in a fracture specimen coupled to a test structure or field structure, and measuring acoustic emission signal in the structure by the false aperture transducer. The calibration curve correlates simulated crack depth percentage with computed peak amplitude ratio of the measured signal.

Abstract: A sound detector device for locating and diagnosing sound in a motor vehicle includes a headphone and a plurality of directional microphones. The sound detector device also includes a main unit having a circuit operatively connected to the headphone and the directional microphones for allowing an operator to diagnose sound in the motor vehicle.

Abstract: A system for remote diagnosis of the state of wear of the suction and delivery valves of reciprocating compressors (20), comprising at least one piezoelectric seismic sensor (12), applied to each cylinder (14) of the compressor (20), which transforms the vibrations generated by the noise of the valves into an electric signal, from which, by means of appropriate amplification and filtering methods, the envelope of the resulting narrow band signal is obtained; the signal obtained is then digitised, and transmitted to a remote diagnostics center (16), in order to be monitored.

Abstract: Device and method for detecting anomaly of an air conditioner, the method including the steps of (1) detecting an acoustic emission signal from a compressor in the air conditioner during operation of the air conditioner, (2) detecting parameters of particular components from the detected acoustic emission signal, and (3) comparing the detected parameters to respective references, to determine anomaly of the air conditioner on the whole, whereby permitting the most reliable detection of anomaly of the air conditioner.

Abstract: Disclosed are an apparatus and a monitoring system and various methods for use in the drying of lumber that use disclosed apparatus. During drying lumber is arranged in multiple courses stacked one on top of the other with multiple wooden stickers substantially evenly spaced from each other between courses and extending across the full width of said stack. The present invention includes a special sticker for inclusion in place of one of the wooden stickers to monitor the AE from the stack and to ultrasonically excite the stack for other measurements. The special sticker in the simplest form, includes a body portion and an acoustic sensor with the body portion constructed of an acoustically conductive material that is sized similarly to a wooden sticker. Also disclosed is a monitoring system which includes a special sticker and signal processing and control electronics coupled to receive an AE signal from the special sticker for monitoring and controlling the drying cycle of the lumber.

Abstract: A nondestructive evaluation (NDE) technique for inspecting or health monitoring of structures and/or specimens by analyzing acoustic emission (AE) signals emitted by the structures and/or specimens. The method and system analyzes acoustic emission (AE) signals emitted by structures and/or specimens. AE signals emitted by the structures and/or specimens are parametrically filtered as a function of parametric filters corresponding to characteristic waveforms of transient AE classes of predefined AE signals. In parametric analysis, the filtering may be pre- or post-recording. In transient AE analysis, the filtering may be prior to transient recording of the transient signals.

Abstract: A transmitter of audible sound waves is disposed at one end of a communicating hole of a cast molded article such as a cylinder block, and a receiver of audible sound waves is disposed at the other end of the communicating hole. The quality of the communicating hole is determined by receiving audible sound waves from a transmitter which have passed through the communicating hole and computing and processing a frequency spectrum of the received audible sound waves based on a reference frequency spectrum.

Abstract: The invention encompasses an electrical apparatus. Such apparatus comprises a first substrate having first circuitry supported thereby. The first circuitry defines at least a portion of a radio frequency identification device. At least one first electrical node is supported by the substrate and in electrical connection with the first circuitry. The apparatus further comprises an input device comprising a second substrate and second circuitry on the second substrate. The second circuitry is in electrical communication with at least one second electrical node. Neither of the first nor second electrical nodes is a lead, and the second electrical node is adhered to the first electrical node to electrically connect the input device with the radio frequency identification device. The invention also encompasses a termite-sensing apparatus. Additionally, the invention encompasses methods of forming electrical apparatuses, and methods for sensing termites.

Abstract: The invention encompasses a device for sensing living organisms. Such device comprises a loop of conductive material extending over a substrate, and an insulative protective material over the loop of conductive material. The device further comprises a circuit which includes the conductive material as a first circuit component and which further includes a transponder as a second circuit component. The transponder is configured to emit a first signal if the loop of conductive material is continuous, and a second signal if the loop of conductive material is broken. The invention also encompasses a device for sensing termites. Such device comprises at least two wooden blocks separated by a gap, and a loop of conductive material within the gap. The device further comprises an insulative protective material over the loop of conductive material.

Abstract: The invention relates to an ultrasonic measuring instrument comprising a housing which contains a transducer for transmitting and receiving ultra-sound waves, and a rotatable mirror placed inside the housing for directing ultra-sound waves coming from the transducer through a tapering window comprised in the housing to an object of measuring outside the housing, and for directing ultra-sound waves which are reflected by the object of measuring and which enter the housing through the window to the transducer. Around, and rotating with the mirror a tube is provided, comprising a recess for the passage of ultra-sound waves.

Abstract: The invention concerns a method of detecting a reflex of the human stapedius muscle, in particular for a hearing test. According to the method, the reflex is triggered by means of an acoustic signal, and the impedance or the variation in impedance brought about by means of the reflex at the eardrum is measured by means of a further acoustic signal. The object of the invention is to further improve the stapedius reflex audiometry method so that it can be applied in practice. To that end, at least two chronologically successive or mutually overlapping substantially identical acoustic signals are used. The information concerning a possible impedance variation at the eardrums obtained by forming the difference between the acoustic characteristics produced and registered by the signals.

Abstract: The invention relates to components made from ductile metallic materials, and to a method with which deformation or the load acting on these materials is to be determined by means of acoustic emissions analysis. For this purpose, a particulate substance which is brittle at least in the temperature range below 400° C. is added to the ductile metallic material, which may preferably be a weldable structural steel, but may also be a ductile light metal alloy (e.g. aluminum alloy), in order to intensify the acoustic emissions behavior. The particles should be brittle at least in the temperature range of use of the component in question, e.g. at room temperature. It is advantageous if the particles are also plastically deformable in the forming temperature range, so that a certain structure (elongate or acicular) of the particles can be achieved, for example during cold work-hardening.

Abstract: A simple, inexpensive signal device indicates the presence of wood-destroying insects, particularly subterranean termites. The signal device comprises a triggering mechanism and a signaling mechanism. The device can be adapted to fit almost all commercially available monitors or bait stations. The triggering mechanism is designed to be released upon destruction by feeding by termites or other wood-eating insects. Upon release, the triggering mechanism is designed to either pull or push a visual signal out of the housing, producing a signal that can be seen from a distance. Using this signal device, the presence of termites can be detected without disturbing the monitor or bait station. Moreover, because the signal is seen outside the housing, the housing is not required to be transparent.

Abstract: The invention encompasses an electrical apparatus. Such apparatus includes RFID circuitry on a first substrate, and sensor circuitry on a second substrate. A receiving structure is associated with one of the RFID circuitry and the sensor circuitry, and at least one connecting structure is associated with the other of the RFID circuitry and the sensor circuitry. The at least one connecting structure is removable received within the receiving structure. The invention also encompasses a method of forming an electrical apparatus. A first substrate and a second substrate are provided. The first substrate has RFID circuitry thereon, and the second substrate has sensing circuitry thereon. A receptacle is joined with one of the RFID circuitry and the sensor circuitry, and has at least one orifice extending therein. At least one prong is joined with the other of the RFID circuitry and the sensor circuitry.

Abstract: A cooking range with an acoustic sensing system for determining the boil state of the contents of a cooking utensil. The acoustic sensing system, which includes at least one acoustic sensor, is positioned on or in the cooking appliance to detect acoustic emissions in one or more specific ranges of frequencies that are characteristic of emissions resulting from the heating and boiling of liquids in a variety of cooking utensils or vessels.

Abstract: Disclosed is a method for testing the photoinduced domain switching of ferroelectric ceramics using AE. A ferroelectric ceramic specimen 4 was tested for the AE signal and photovoltaic current upon application of light. Light emanating from a xenon lamp 1 is focused into a specimen 4 through a waveguide 2 and a lens 3. Raw AE signals are detected through an AE sensor 5. The output signals from the AE sensor 5 are forwarded to a bandpass filter 7 which filtered the signals. Then, the AE signals are amplified by 40 dB by a pre-amplifier 8 and further by 30 dB by an AET 5500 system 10 which is connected to a computer 9 for analyzing the signals. The AE events which show a peak amplitude greater than or as great as a predetermined threshold voltage are counted with respect to an irradiation period of time, followed by calculating an occurrence rate of the AE event counts. From these data, the activity of the photoinduced domain switching can be qualitatively evaluated.

Abstract: Modal frequencies of known good sample parts (SN) are analyzed to determine a pattern which will identify acceptable material and dimensional variations. The data obtained by analysis is then archived. Production parts are then measured at the modal frequencies and the production parts are accepted or rejected after pattern analysis of each part by comparing the production part with response to the pattern identified as acceptable for material and dimensional variations. Production part data is archived for future testing. This procedure is repeated throughout the lifetime of a part, and may be used on parts which are part of an assembly, including other unmeasured parts.

Abstract: A method and an apparatus for detecting and measuring cracks in plate-like structures using acoustic emission technique are disclosed. A false aperture transducer is designed to provide a criterion for filtering out extraneous noise in the acoustic emission signal based on modal analysis by computing the ratio of the high-frequency peak amplitude to low-frequency peak amplitude of the signal. A calibration curve correlating crack depth to the amplitude ratio can be obtained by simulating crack growth in a fracture specimen coupled to a test structure or field structure, and measuring acoustic emission signal in the structure by the false aperture transducer. The calibration curve correlates simulated crack depth percentage with computed peak amplitude ratio of the measured signal.

Abstract: Method and apparatus for detecting failure of tensioned reinforcements in a structure by means of a plurality of acoustic or seismic detectors disposed about the structure in a known arrangement, processing signals from the detectors to determine frequency contents and origins, and identifying simultaneous signals as due to the failure of tensioned reinforcements in the structure when they meet spectral and origin criteria.

Abstract: During a passive initial stage, acoustic signals received by a receiving transducer array are recorded, and the corresponding electric signals are stored. To search for the possible presence of a sound source whose contribution to the signal recorded in the passive initial stage may be faint, window of each electric signal stored in the initial stage is time reversed and amplified to produce excitation signals which are applied to emitting transducers of an array corresponding to that of the receiving transducers. The acoustic echo signals received by the receiving transducers are recorded, and the corresponding electric signals are stored, and can be exploited to detect the possible presence of a reflecting sound source.

Abstract: The fouling state of a polymeric membrane within the high pressure housing of a spiral wound or a hollow fiber membrane module is determined. An ultra sonic transducer positioned with its emitting face in physical engagement with the outer surface of the housing is pulse energized by a pulser/receiver device. A membrane echo signal is detected by a receiver of the pulser/receiver device. A reference echo signal indicative of a fouled or an unfouled state of the membrane is compared to the echo signal to determine the membrane fouling state. The echo to reference comparing step can be based upon comparing amplitude domain signals, comparing time-domain signals, comparing combinations of amplitude domain and time-domain signals, and comparing transformations of amplitude domain and time-domain signals.

Abstract: The present invention provides a method of determining the boil states of a liquid as measured by an acoustic sensor which measures the acoustic signal generated by the liquid as it is heated. The acoustic signal is smoothed and a first derivative of the acoustic signal is calculated. Also the frequency of the acoustic signal is measured. Derivative inflection points, zero slope points, and acoustic signal frequencies are utilized to determine the pre-simmer, simmer, pre-boil, boil, boil dry, and boil over states of the liquid.

Abstract: A sample-holding container having a structure that may be heated and internally pressured with water to subject the sample to its anticipated working conditions as the sample is tested. A single, oil-encapsulated transducer transmits acoustic energy waves through a chamber containing the sample and receives reflections of the waves from the chamber floor. The transducer converts the received reflected acoustic waves to an electrical signal that is analyzed to evaluate the sample. Pressurized water in contact with the sample is employed in the chamber to pressurize the sample during the test. A movable, pressure-responsive barrier between the oil encapsulating the transducer and the water pressurizing the sample maintains the transducer and the sample at the same pressure. A thin membrane between the transducer and the sample permits the transducer to be in physical contact with the sample while protecting the transducer from chemical exposure.

Abstract: The present invention provides an ultrasonic processor for the treatment, for example, dispersing, emulsifying, dissolving, mixing or deagglomerating of materials by the application of ultrasound thereto, wherein said ultrasonic processor comprises a hollow elongate enclosure member with a plurality of transducers fixed to the exterior of said elongate enclosure member along the length thereof; each said transducer being capable of applying ultrasonic waves to materials passing through the interior of said hollow elongate enclosure member; and control means for control and/or regulating the frequency of such ultrasonic waves produced by said transducers; and sensing means for the determination of the nature of the materials passing through the interior of said hollow elongate enclosure member, wherein said sensing means actuates said transducers to produce ultrasonic waves at the prescribed frequency in accordance with the nature of said materials to be treated.

Abstract: An acoustic rotor monitor that is an autonomous self-powered measurement instrument which can detect embedded and hidden fatigue cracks in remotely inaccessible devices such as helicopter rotor system components. A predictive maintenance-related problem for rotor craft is the detection of fatigue cracks as a continuous real-time monitoring process under dynamic rotor system loading conditions. The rotor monitor focuses on the embedding an acoustic emission-based smart sensor directly into the rotor system to measure the high frequency stress waves indicating that a structural crack has propagated as a "self-powered" measurement without reducing structural integrity.