Abstract: A method for determining an absolute flow rate of a volume or mass flow includes measuring continuous reference values, where each individual reference value is in a direct physical relationship to the flow rate, determining reference value fluctuations, and calculating or mapping the absolute flow rate as a function of a numerical and/or statistic evaluation function of the reference value fluctuations, in particular a fluctuation value generated therefrom. A measurement configuration for implementing the method is also provided.

Abstract: At least one embodiment is directed toward one or more disposable devices suitable for use in a surgical field of an operating room. One device includes a sensor communicatively coupled to a wand to register points of interest on a first or second bone of a muscular-skeletal system and transmits location data related to the points of interest to the sensor to assess orthopedic alignment with the points of interest.

Abstract: A disposable tool suitable for use in orthopedic alignment that registers points of interest on a first and second bone and transmits location data related to the points of interest to the sensor to assess orthopedic alignment with the points of interest. A display can report and visually display alignment information in real-time.

Abstract: A motor vehicle having a gas concentration sensor and a method for measuring gas concentration using the gas concentration sensor the gas concentration sensor having a sound transmitter, a sound receiver and a control device by which a phase shift between the sound signal transmitted by the sound transmitter and a sound signal received by the sound receiver can be controlled to a predefinable phase shift. A change in a composition of a gas mixture can be detected by an analysis unit on the basis of a change in frequency of the sound signal relative to a frequency of a reference sound signal.

Abstract: A fuel quality sensor is provided for use with an engine system. The fuel quality sensor may have a single sensing element configured to sense a thermodynamic property of an unknown mixture of gaseous fuel, and a heating element configured to increase a temperature of the unknown mixture of gaseous fuel at the single sensing element to multiple different temperature levels. The fuel quality sensor may also include a microprocessor configured to calculate a fuel parameter of the unknown mixture of gaseous fuel as a function of only the thermodynamic property sensed at the multiple different temperature levels.

Abstract: A breathing apparatus has a first delivery device for adding a volume of a substance to a gas flow, the delivery device having a gas inlet and a gas outlet. A unit monitors a presence of the substance in a gas downstream the delivery device using a first sensor unit at the gas outlet that provides a first measurement value based on an acoustic property of a gas in a first conduit. A second sensor unit at the gas inlet provides a second measurement value based on an acoustic property of a gas present in the second conduit. A control unit determines the presence of the substance based on the first measurement value or based on a comparison of the first measurement value and the second measurement value.

Abstract: An apparatus for detecting a presence of at least one analyte in a gas sample. The apparatus comprises a pump for drawing a gas sample from an ambient air, a passage having first and second ends, a chamber connected to the first end and containing a concentrating element for collecting at least one analyte from the gas sample, a chromatographic separator connected to a second end of the passage, and a gas source for streaming a carrier gas via the chamber to transfer the at least one analyte toward at least one chemical detector, via the chromatographic separator, in a first direction. The pump draws the gas sample via the chamber in a second direction and the first and second directions are substantially opposing to one another.

Abstract: A sound velocity sensor is defined by a hermetic multi-chambered enclosure for containing flowing gases and mixtures of gases. The contained flowing gases are acoustically excited and the acoustic energy is measured over a fixed distance between a first sending end of the enclosure and a receiving end. The speed of sound of the gases are determined by comparing the energy transmitted through the flowing gases at various frequencies so as to precisely determine the resonant frequency of the gases flowing through the enclosure. In accordance with the present design, the chambers of the enclosure include internal transition shapes therebetween for optimizing the transmission of acoustic energy through the flowing gases and also enhancing one or more additional resonant modes at higher useful frequencies. The transition shapes used in connection with the sensor can be at least one of parabolic, hyperbolic, linear and exponential in nature.

Abstract: The present disclosure is directed to a temperature detector for detecting a temperature of a component. The temperature detector may receive a first signal indicative of the temperature of the component, with the first signal being received from a first type of temperature sensor. The temperature detector may further receive a second signal indicative of the temperature of the component, with the second signal being received from a second type of temperature sensor different from the first type of temperature sensor. The temperature detector may combine the first and second signals to generate an output indicative of the temperature of the component.

Abstract: The described sensor allows determination of the concentration of a gas in a two-component mixture at variable pressure by measuring the diffusivity and the thermal conductivity. The sensor is provided to alternately heat the membrane (12) of a thermally conductive cell (1) and allow it to cool such that the temperature TM of the membrane passes from a first stable value to a second stable value and vice versa via a transient mode. The cell produces a signal representative of the temperature TM of the membrane and the sensor extracts from the signal a first and a second parameter that respectively relate to said first stable value and said transient mode of the signal. A value of the concentration of said gas and of the pressure of said two-mixture is calculated from these two parameters.

Abstract: Various embodiments are directed to an apparatus and method of driving an end effector coupled to an ultrasonic drive system of a surgical instrument. The method comprises generating at least one electrical signal. The at least one electrical signal is monitored against a first set of logic conditions.

Abstract: There is provided a sensor assembly (200) for measuring physical properties of a gas under pressure within a pressure vessel (100). The sensor assembly (200) comprises a housing and a piezoelectric oscillator (202) for immersion in the gas within the pressure vessel (100). The sensor assembly (200) is arranged, when immersed in said gas, to measure the density of the gas within the pressure vessel (100). The housing comprises a first chamber and a second chamber. The first chamber is in fluid communication with the second chamber and substantially encloses said piezoelectric oscillator. The second chamber is in fluid communication with the interior of the pressure vessel. By providing such an arrangement, the true contents (i.e. mass) of fluid in a pressure vessel such as a cylinder can be measured directly and accurately.

Abstract: At least two sound pressure sensors in parallel with each other are inserted into a liquid to which waves are applied. The sound pressure sensors have a bar-like shape and the same sensitivity. In a first synchronized state waves detected by the sound pressure sensors are synchronized with each other. The sound pressure sensors are moved relative to each other in a longitudinal direction, to break the first synchronized state and then establish a second synchronized state in which the waves detected by the sound pressure sensors are again synchronized with each other. A wavelength of the detected waves is determined according to a quantity of the relative movement of the sound pressure sensors between the first and second synchronized states. The detection of a wavelength of waves applied to the liquid is usable to evaluate and control a total amount of dissolved gases in the liquid.

Abstract: The present disclosure relates to a valproic acid biosensor. In some embodiments, the valproic acid biosensor may comprise a microcantilever, a self-assembly monolayer, and a valproic acid antibody layer. The self-assembly monolayer may immobilize on the microcantilever surface. The valproic acid antibody layer may immobilize on the self-assembly monolayer. The valproic acid antibody layer may be used to bind with valproic acid drug samples. The present disclosure further relates to methods for measuring the concentration of valproic acid drug samples.

Abstract: In the present invention a controllable acoustic source (14) in connection with the process fluid (10) emits a signal (18) into the fluid (10), consisting of a suspension of particles (12), being volumes of gas, liquid or solid phase. The controllable acoustic signal (18) is allowed to interact, with the particles (12), and the acoustic (pressure) signals (22) resulting from such an interaction is measured preferably via a sensor (24). A spectrum is measured. The spectrum is used to predict properties, content and/or size of the particles (12) and/or used to control a process in which the process fluid (10) participates. The prediction is performed in the view of the control of the acoustic source (14). The used acoustic signal has preferably a frequency below 20 kHz.

Abstract: An acoustic sensor includes a side wall, closed at each end by an end wall, to form a substantially cylindrical cavity, a transmitter and a receiver operatively associated with first and second respective end walls. Properties of the relative dimensions of the cavity are configured to create a desired oscillatory motion of the end walls, and oscillations of a fluid pressure in the cavity, to generate an electrical signal via the receiver to be output from the sensor. An array of acoustic sensors can be connected to allow calibration of one of the array of sensors.

Abstract: A method and apparatus of determining gas transport time from an input port to first and second ultrasonic detectors in a flow conduit for an aspirated smoke detector includes first measuring transit time of ambient air between the detectors. Then a different gas is injected into the conduit and the time of injection is stored. The transit time is measured at least intermittently between the two ultrasonic detectors until a change therein is detected. A time of detected change is subtracted from the time of injection to establish a transport time for the aspirated smoke detector.

Abstract: Chemical sensors such as carbon dioxide sensors and methods for making such sensors are disclosed. An example carbon dioxide sensor may include a substrate, with a sensing beam supported by the substrate. The sensing beam may be configured to resonant. A sensing layer may be disposed on the sensing beam, wherein the sensing layer may include an amino group and is configured to sense carbon dioxide. In some instances, a reference beam may also be supported by the substrate, and may be configured to resonant. A reference layer may be disposed on the reference beam, wherein the reference layer may includes an amino group that has been poisoned so that it will be substantially non-sensitive to carbon dioxide.

Abstract: An apparatus and method estimate fluid mass in a cryogenic tank that holds a multiphase fluid comprising a liquid and a vapor. The apparatus comprises a level sensor, a pressure sensor and a computer. The level sensor provides a parameter representative of a level of the liquid. The pressure sensor provides a pressure signal representative of vapor pressure inside the cryogenic tank. The computer is operatively connected with the level sensor and the pressure sensor to receive the parameter and the pressure signal, and is programmed to determine the level from inputs comprising the parameter, to calculate a first volume of the liquid from inputs comprising the level, and to calculate a first mass of the liquid from inputs comprising the first volume and the pressure signal.

Abstract: A method of analyzing a sample that includes applying a first set of energies at a first set of frequencies to a sample and applying, simultaneously with the applying the first set of energies, a second set of energies at a second set of frequencies, wherein the first set of energies and the second set of energies form a multi-mode coupling. The method further includes detecting an effect of the multi-mode coupling.

Abstract: In representative embodiments, a system includes an acoustic emitter, a controller, an optical sensor, and an indicator for indicating a detection of a predetermined trace chemical vapor by the optical sensor. The acoustic emitter is positioned at a predetermined distance above the ground surface and configured to project a beam of acoustic energy toward the ground surface with a variable angle of incidence ?. The controller is configured to control the acoustic emitter to vary the angle of incidence of the acoustic beam within the variable angle of incidence ?, while the optical sensor is configured for standoff sensing of a trace chemical vapor proximate the ground surface. Excitation of the ground surface, particularly at a critical angle of incidence ?, causes the release of trace chemical vapors from a buried source and the soil into the air above the buried source.

Abstract: In an ultrasonic apparatus for measuring the concentration of gas provided with two ultrasonic oscillators for transmitting/receiving an ultrasonic wave, arranged opposite to each other in piping through which a sample gas flows, a temperature sensor, and a pressure sensor, an ultrasonic method and apparatus that can accurately measure gas concentration regardless of pressure of the sample gas are provided as an ultrasonic apparatus for measuring the concentration of gas comprising concentration calculating means for calculating sample gas concentration based on a propagation speed correction coefficient by pressure.

Abstract: Technologies are generally described for gas filtration and detection devices. Example devices may include a graphene membrane and a sensing device. The graphene membrane may be perforated with a plurality of discrete pores having a size-selective to enable one or more molecules to pass through the pores. A sensing device may be attached to a supporting permeable substrate and coupled with the graphene membrane. A fluid mixture including two or more molecules may be exposed to the graphene membrane. Molecules having a smaller diameter than the discrete pores may be directed through the graphene pores, and may be detected by the sensing device. Molecules having a larger size than the discrete pores may be prevented from crossing the graphene membrane. The sensing device may be configured to identify a presence of a selected molecule within the mixture without interference from contaminating factors.

Abstract: The present invention relates generally to the detection of alcohol. The present invention relates more particularly to the film bulk acoustic wave resonator-based devices, and their use in the sensing of ethanol and/or acetone. One aspect of the invention is a method for detecting ethanol, acetone or both in a gaseous sample including: providing a film bulk acoustic wave resonator having a zinc oxide piezoelectric layer; exposing the film bulk acoustic wave resonator to the gaseous sample; determining the resonant frequency of the film bulk acoustic wave resonator; and determining the concentration of ethanol, the concentration of acetone, or both in the gaseous sample using the resonant frequency of the film bulk acoustic wave resonator.

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 to detect a phase separation of gasoline and ethanol may include the steps of generating a sound signal in a tank, determining a speed of the sound signal, determining an interface level in the tank, determining the speed of the sound signal below the interface level and determining the phase separation based upon the speed of the sound signal.

Abstract: A sensor chip (1030) for gas has cells (200) for emitting and receiving ultrasound and is configured for a sufficiently large frequency range and for measuring concentration of at least one of the gas components based on at least two responses within the range. The frequency range can be achieved by varying the size of cell membranes (230), varying bias voltages, and/or varying air pressure for an array (205) of cMUTs or MEMS microphones. The sensor chip can be applied in, for example, capnography. A measurement air chamber (515) is implemented in the respiratory pathway (400), and it and/or the pathway may be designed to reduce turbulence in the exhaled breath (120) subject to ultrasound interrogation. The chip (1030) can be implemented as self-contained in the monitoring of parameters, obviating the need for off-chip sensors.

Abstract: An acoustical transformer having a last matching section that includes a protective barrier of low permeability. The protective barrier is in contact with a test medium. In one embodiment, the protective barrier comprises one or more low permeability layers, such as a metallic foil or metallic coating(s) disposed on a low impedance layer such as polyimide, so that the low impedance layer and the protective barrier constitute the last matching section of the acoustical transformer. In other embodiments, the protective barrier comprises a fluoropolymer. A method for determining the thicknesses of the various layers of the acoustical transformer for enhanced performance is also disclosed.

Abstract: There is provided a meter for measuring the molecular weight of a gas, the meter comprising a housing having an inlet and an interior for receiving said gas to be measured, a sensor assembly comprising a high-frequency planar piezoelectric crystal oscillator located within said housing so that, in use, the piezoelectric crystal oscillator is in contact with said gas, said sensor assembly being arranged: to drive the piezoelectric crystal oscillator such that the piezoelectric crystal oscillator resonates at a single resonant frequency; to measure said single resonant frequency of said piezoelectric crystal oscillator to determine the density of gas; and to determine from the density, determined or pre-determined pressure of the gas and determined or pre-determined temperature of the gas, the molecular weight of the gas.

Abstract: The invention relates to a device (7) for collecting particles and microorganisms present in ambient air, the device comprising a cyclone enclosure (8) for centrifuging air, the enclosure being of conical or frustoconical shape, external air inlet means (16) for admitting air into the enclosure (8), and air outlet means connected by coupling means (19, 20, 21) to air inlet filter means (4) of an individual motorized respiratory protection appliance (A).

Abstract: A hybridization detecting device, wherein a probe cell has a body of semiconductor material forming a diaphragm, a first electrode on the diaphragm, a piezoelectric region on the first electrode, a second electrode on the piezoelectric region and a detection layer on the second electrode. The body accommodates a buried cavity downwardly delimiting the diaphragm.

Abstract: A tunable nanoscale resonator has potential applications in precise mass, force, position, and frequency measurement. One embodiment of this device consists of a specially prepared multiwalled carbon nanotube (MWNT) suspended between a metal electrode and a mobile, piezoelectrically controlled contact. By harnessing a unique telescoping ability of MWNTs, one may controllably slide an inner nanotube core from its outer nanotube casing, effectively changing its length and thereby changing the tuning of its resonance frequency. Resonant energy transfer may be used with a nanoresonator to detect molecules at a specific target oscillation frequency, without the use of a chemical label, to provide label-free chemical species detection.

Abstract: Techniques are generally described for detecting a concentration level of at least one gas. Some example devices may include a sensor including conductive plate on a surface of dielectric including a nanotube layer formed thereon. The conductive plate and the nanotube layer form a resonator that resonates at a frequency in response to an interrogation signal. The nanotube layer may be configured to associate with one or more gas molecules. The frequency at which the resonator resonates may shift according to which gas molecules are associated with the nanotube layer to identify a particular gas. An amount of resonance may be exhibited as a resonant response signal. An amplitude of the resonant response signal may be indicative of the concentration level of the detected gas.

Abstract: A dissolved nitrogen concentration monitoring method is used for monitoring a dissolved nitrogen concentration of a cleaning liquid when an ultrasonic wave is irradiated onto the cleaning liquid in which a substrate is dipped. The method includes measuring an amount of increase of a dissolved oxygen concentration of the cleaning liquid resulting from an oxygen molecule generated from a water molecule as a result of a radical reaction caused by ultrasonic wave irradiation. A dissolved nitrogen concentration of the cleaning liquid is calculated from the measured amount of increase of dissolved oxygen concentration based on a predetermined relationship between a dissolved nitrogen concentration and an amount of increase of dissolved oxygen concentration.

Abstract: A carbon dioxide sensor comprising a first beam that includes a functionalized surface and a second beam that includes a functionalized surface such that reduced-drift differential sensing of carbon dioxide may be performed by monitoring changes in the resonant frequency of the first beam relative to the resonant frequency of second beam.

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: An exemplary gas sensing system includes a gas sensing unit, a detecting unit, and a processing unit. The gas sensing unit includes a quartz crystal substrate, a first electrode layer, a second electrode layer, a first activating layer, and a sensor medium layer having adsorption ability and desorption ability to chemical gas. The detecting unit is electrically connected with the first electrode and the second electrode, and is configured for detecting a frequency change of the gas sensing unit before and after adsorbing the chemical gas. The processing unit is electrically connected with the detecting unit, and is configured for obtaining a mass change of the gas sensing unit according to the frequency change.

Abstract: Methods and apparatuses for determining whether a fluid has been introduced into an assay measurement apparatus involving delivering a fluid to a surface of a resonant device. The methods also involve monitoring an electrical signal output by the resonant device, wherein properties of the electrical signal vary based on physical properties of the fluid in contact with the surface of the resonant device and determining if the electrical signal output by the resonant device satisfies a predetermined condition indicative of the presence of the fluid.

Abstract: A method for operating a sensor element, in particular a lambda sensor, for determining the concentration of a gas component of a gas mixture, in which the gas component is removed from a measuring gas chamber by applying a pump voltage and the concentration of the gas component in the gas mixture is inferred therefrom. Oscillations of the pump current caused by dynamic pressure variations are taken into consideration for a correction of the sensor signal in that a frequency analysis of the pump current is carried out.

Abstract: A system having reduced gas interference that includes a fluid chamber and a resonant sensor device in fluid communication with a fluid in the fluid chamber. The system includes a fluid control device adapted to change at least one of the fluid flow or pressure within the fluid chamber to achieve substantial wetting of surfaces in proximity to the resonant sensor device. Fluid surfaces of the system can include a material to increase the wettability (e.g., hydrophilicity) of the fluid surfaces.

Abstract: To provide a quartz sensor capable of detecting a sensing target with high sensitivity also in measurement in a liquid phase in which a difference in Q values at the time of measurement in the liquid phase and in a vapor phase is small. In a quartz sensor 1 including an AT-cut quartz plate 11 having a capture layer (absorbing layer) 12 formed on one surface (XZ? surface) thereof and detecting a sensing target based on an amount of change in a frequency of a quartz resonator 10 caused when the sensing target is absorbed by the capture layer 12, there are formed electrodes 13 for oscillating the quartz plate 11 on end faces (XY? surfaces) mutually opposite in a Z? direction of the surface of the quartz resonator 10 on which the capture layer 12 is formed (XZ? surface).

Abstract: A surface acoustic wave sensor device includes a main body and a liquid controller disposed external to the main body. The main body includes a sample chamber, a surface acoustic wave sensor connected to the sample chamber, a first disposal chamber connected to the surface acoustic wave sensor and channels connecting the sample chamber, the surface acoustic wave sensor and the first disposal chamber. The liquid controller controls flow of a sample through the main body.

Abstract: An electronic microbalance made in a semiconductor body accommodating an oscillating circuit adjacent to a diaphragm. A stack formed by a first electrode, a second electrode, and a piezoelectric region arranged between the first and the second electrode extends above the diaphragm. Any substance that deposits on the stack causes a change in the mass of the microbalance and thus in the resonance frequency of a resonator formed by the microbalance and by the oscillating circuit and can thus be detected electronically. A chemical sensor is obtained by forming a sensitive layer of a material suitable for binding to target chemicals on the stack. The sensitivity of the microbalance can be increased by making the first electrode of molybdenum so as to increase the piezoelectric characteristics of the piezoelectric region.

Abstract: A sound velocity sensor is defined by a hermetic multi-chambered enclosure for containing flowing gases and mixtures of gases. The contained flowing gases are acoustically excited and the acoustic energy is measured over a fixed distance between a first sending end of the enclosure and a receiving end. The speed of sound of the gases are determined by comparing the energy transmitted through the flowing gases at various frequencies so as to precisely determine the resonant frequency of the gases flowing through the enclosure. In accordance with the present design, the chambers of the enclosure include internal transition shapes therebetween for optimizing the transmission of acoustic energy through the flowing gases and also enhancing one or more additional resonant modes at higher useful frequencies. The transition shapes used in connection with the sensor can be at least one of parabolic, hyperbolic, linear and exponential in nature.

Abstract: An apparatus for determining the proportion of gases in a gas mixture, has a measurement chamber having a chamber defining structure, a gas inlet and a gas outlet, an ultrasound source and an ultrasound detector mounted such that the ultrasound source is capable of transmitting ultrasound through the chamber to the ultrasound detector; a temperature sensor mounted such that the sensor is capable of sensing the temperature in the chamber. The chamber defining structure is adapted to amplify thermal exchange with a gas content in the chamber so as to suppress a temperature change in the chamber.

Abstract: An electrochemical piezoelectric sensor is disclosed. The sensor includes a piezoelectric substrate, three (or more) electrodes over a first surface of the substrate, and another electrode over a second (opposing) surface of the substrate. An ionic liquid in the form of a film is adhered, bound, immobilized, or otherwise positioned over the substrate and electrodes of the first surface. The ionic liquid film permits the absorption and detection of analytes from a gaseous sample, for environmental gases, example explosive vapors and/or explosive vapor species in the gaseous sample. Detection (optionally including analyte quantitation and qualitative identification) can be performed by both electrochemical and piezoelectric techniques using a single sensor. Systems incorporating and methods of using the electrochemical piezoelectric sensor also are disclosed.

Abstract: It is presented a method for detecting a gas (G). Acoustic waves (Wt) are generated and transmitted via a wave generating and sensing means (2) towards a reflecting wall (3) and thereafter reflected acoustic waves (Wt) are detected by the wave generating and sensing means (2) wherein a presence of the gas (G) is detected by determining a change in an output signal of the wave generating and sensing means (2). A gas detector (1) is also presented.

Abstract: Disclosed is a method for detecting a low concentration gas. In the method, a measurand gas containing the target gas in a concentration of 50 ppm or less is supplied to an oscillation element which contains a quartz crystal resonator and a zeolite including a metal complex (such as a zeolite including a cobalt phthalocyanine complex) present on or above the quartz crystal resonator. The target gas is then detected through a change in resonance frequency of the quartz crystal resonator, the change being caused by the adsorption of the target gas by the metal-complex-including zeolite.

Abstract: Resonant sensors, preferably having floating bilayer symmetry, and their methods of use is determining the presence, amount or binding kinetics of an analyte of interest in a test sample are disclosed. The test sample may be a liquid or gas.

Abstract: All-optical photoacoustic spectrometer sensing systems (PASS system) and methods include all the hardware needed to analyze the presence of a large variety of materials (solid, liquid and gas). Some of the all-optical PASS systems require only two optical-fibers to communicate with the opto-electronic power and readout systems that exist outside of the material environment. Methods for improving the signal-to-noise are provided and enable mirco-scale systems and methods for operating such systems.