Abstract: A flow sensor includes a conduit and an ultrasonic transceiver. The conduit has an inner surface and an outer surface. The inner surface defines a flow passage through which a fluid may flow in a flow direction. The ultrasonic transceiver is coupled to, and surrounds a portion of, the outer surface of the conduit. The ultrasonic transceiver is configured to transmit ultrasonic waves into the fluid that propagate in a direction that is parallel to the flow direction, receive ultrasonic waves, and supply sensor signals representative of the received ultrasonic waves.

Abstract: A flow sensor includes a plurality of ultrasonic transceivers and signal processing circuitry. The transceivers are coupled to a portion of the outer surface of a duct, and each is configured to transmit ultrasonic waves into a fluid, receive ultrasonic waves, and supply sensor signals representative of the received ultrasonic waves. The signal processing circuitry is configured to supply separate excitation signals to each of the ultrasonic transceivers, receive the sensor signals supplied by each of the ultrasonic transceivers, and generate, in response to the sensor signals, a flow signal representative of fluid flow in the flow passage. Each of the excitation signals has a different phase, such that the ultrasonic waves transmitted by each of the ultrasonic transceivers at least selectively combine to propagate in an adjustable direction relative to the flow direction.

Abstract: A flow sensor includes a plurality of ultrasonic transceivers and signal processing circuitry. The transceivers are coupled to a portion of the outer surface of a duct, and each is configured to transmit ultrasonic waves into a fluid, receive ultrasonic waves, and supply sensor signals representative of the received ultrasonic waves. The signal processing circuitry is configured to supply separate excitation signals to each of the ultrasonic transceivers, receive the sensor signals supplied by each of the ultrasonic transceivers, and generate, in response to the sensor signals, a flow signal representative of fluid flow in the flow passage. Each of the excitation signals has a different phase, such that the ultrasonic waves transmitted by each of the ultrasonic transceivers at least selectively combine to propagate in an adjustable direction relative to the flow direction.

Abstract: The present disclosure relates to methods and apparatus for detecting when respiratory cartridges of a respirator have reached their end-of-service-life. In some instances, two or more respiratory cartridges are removably connectable to a respirator housing, where each of the two or more respiratory cartridges receives ambient air and deliver cleaned air to the respirator housing. One of the respiratory cartridges may be configured to have a lower adsorption capacity than the remaining respirator cartridges. A gas sensor may be situated downstream of the reduced capacity respirator cartridge, and may detect an increased concentration of the targeted gas in the cleaned air delivered by the reduced capacity respiratory cartridge. When detected, an end-of-service-life indication may be provided to the user.

Abstract: A flow sensor includes a conduit and an ultrasonic transceiver. The conduit has an inner surface and an outer surface. The inner surface defines a flow passage through which a fluid may flow in a flow direction. The ultrasonic transceiver is coupled to, and surrounds a portion of, the outer surface of the conduit. The ultrasonic transceiver is configured to transmit ultrasonic waves into the fluid that propagate in a direction that is parallel to the flow direction, receive ultrasonic waves, and supply sensor signals representative of the received ultrasonic waves.

Abstract: A piston prover apparatus, method and system for accurately measuring the flow rate of a fluid by the measurement of the position of an internal piston. The piston can be integrated with a poppet valve arrangement located within a cylinder in order to permit fluid (e.g., cryogenic fluid) to pass through an orifice passage when the piston is drawn to an upstream position prior to proving the flow. An actuator in association with a motor and an encoder can be located inside the cylinder. The motor drives the piston to the upstream position of the cylinder when a proving run is initiated. Once the piston is released for the proving run, the initial and final positions of the piston can be accurately measured along with the transit time.

Abstract: A piston prover apparatus, method and system for accurately measuring the flow rate of a fluid by the measurement of the position of an internal piston. The piston can be integrated with a poppet valve arrangement located within a cylinder in order to permit fluid (e.g., cryogenic fluid) to pass through an orifice passage when the piston is drawn to an upstream position prior to proving the flow. An actuator in association with a motor and an encoder can be located inside the cylinder. The motor drives the piston to the upstream position of the cylinder when a proving run is initiated. Once the piston is released for the proving run, the initial and final positions of the piston can be accurately measured along with the transit time.

Abstract: The present disclosure relates to methods and apparatus for detecting when respiratory cartridges of a respirator have reached their end-of-service-life. In some instances, two or more respiratory cartridges are removably connectable to a respirator housing, where each of the two or more respiratory cartridges receives ambient air and deliver cleaned air to the respirator housing. One of the respiratory cartridges may be configured to have a lower adsorption capacity than the remaining respirator cartridges. A gas sensor may be situated downstream of the reduced capacity respirator cartridge, and may detect an increased concentration of the targeted gas in the cleaned air delivered by the reduced capacity respiratory cartridge. When detected, an end-of-service-life indication may be provided to the user.

Abstract: An integrated DPF loading and failure sensor with two particulate matter sensors one located upstream of the filter and the other located downstream of the filter. The sensors are integrated into the leading and trailing edges of the filter. Integrating two particulate matter sensors with the DPF will allow the proper interval between reconditioning of DPF, since the particulate matter collected on the filter is measured and not estimated. The upstream sensor determines the amount of particulate matter entering the filter. In addition to using the first sensor for loading, the second sensor, at the trailing face of the filter, can be used to determine break-through of the DPF. The second sensor measures the particulate matter escaping the filter.

Abstract: A fluid conveyance apparatus having more than one particulate matter sensing probe situated at two or more locations on the apparatus. Signals from the probes from at least two locations may indicate particulate matter flowing within a fluid through the conveyance apparatus. The times between signals may be indicated the rate of movement of the particulate matter in the conveyance apparatus and also a flow rate and direction of the fluid. The sensing probe signals may be processed into control signals that may go to a flow control mechanism. An example application of the flow control mechanism may be for an exhaust gas recirculation system of an engine.

Abstract: Method and system of onboard diagnostics in engine emissions monitoring, particularly for detecting anomalous cylinder behavior. In some embodiments, at least one sensor in the exhaust path measures electric charge that is indicative of particulate matter. In some embodiments, at least one sensor measures oxides of nitrogen.

Abstract: A sensor network provides the ability to detect, classify and identify a diverse range of agents over a large area, such as a geographical region or building. The network possesses speed of detection, sensitivity, and specificity for the diverse range of agents. Different functional level types of sensors are employed in the network to perform early warning, broadband detection and highly specific and sensitive detection. A high probability of detection with low probability of false alarm is provided by the processing of information provided from multiple sensors. A Bayesian net is utilized to combine probabilities from the multiple sensors in the network to reach a decision regarding the presence or absence of a threat. The network is field portable and capable of autonomous operation. It also is capable of providing automated output decisions.

Abstract: A system having a particulate matter sensor in an exhaust stream of an engine upstream from a particulate filter and another such sensor downstream from the filter. There may also be an exhaust gas recirculation (EGR) control on the engine. The amount of particulate matter in or loading of the filter may be determined by the upstream filter. The working condition of the filter may be determined by the downstream sensor. The filter may have a heater and control for providing operational and particulate matter burn-off temperatures to the filter. A processor may be connected to the sensors, the EGR control and the filter heater control.

Abstract: A sensor is disclosed that includes an electrolyte pump in fluid communication with an electrochemical cell and an ion selective electrode. The electrochemical cell may include a gold cathode and a platinum anode. The sensor may include an electrolyte reservoir as well as an optional electrolyte waste reservoir. Methods of sensing chlorine dioxide are also disclosed.

Abstract: A sensor network provides the ability to detect, classify and identify a diverse range of agents over a large area, such as a geographical region or building. The network possesses speed of detection, sensitivity, and specificity for the diverse range of agents. Different functional level types of sensors are employed in the network to perform early warning, broadband detection and highly specific and sensitive detection. A high probability of detection with low probability of false alarm is provided by the processing of information provided from multiple sensors. A Bayesian net is utilized to combine probabilities from the multiple sensors in the network to reach a decision regarding the presence or absence of a threat. The network is field portable and capable of autonomous operation. It also is capable of providing automated output decisions.

Abstract: A photoelectrocatalytic sensor system for measuring oxidizable impurities in air. The sensor system may include a transistor having an electrode and a channel for the flow of current, a photocatalytic material coated onto the electrode of the transistor, a light source for producing an ultraviolet light beam onto the photocatalytic material, and a sensor for measuring the flow of current.

Abstract: A respirator filter removes toxic chemical threats by first heating an air stream, and then contacting it with a catalyst and adsorbent at conditions conducive to toxicity elimination by reaction. The air stream may then be cooled prior to being provided to a wearer of the respirator. A pump is included in various embodiments.

Abstract: A fluid conveyance apparatus having more than one particulate matter sensing probe situated at two or more locations on the apparatus. Signals from the probes from at least two locations may indicate particulate matter flowing within a fluid through the conveyance apparatus. The times between signals may be indicated the rate of movement of the particulate matter in the conveyance apparatus and also a flow rate and direction of the fluid. The sensing probe signals may be processed into control signals that may go to a flow control mechanism. An example application of the flow control mechanism may be for an exhaust gas recirculation system of an engine.

Abstract: A sensor for detecting particulate matter in an exhaust stream of an engine. The sensor may be a spark-plug-like device having an extended center electrode composed of a stainless steel or other material. The electrode may have a thin passivating layer formed on it. The layer may be grown or deposited on the electrode within the exhaust system. The sensor may detect charge transients indicative of particulate concentration in the exhaust stream. Information about particulate matter in the exhaust system along with other engine information may be processed for controlling or adjusting parameters of the engine to affect the particulate matter in the exhaust system.

Abstract: A micro plasma sensor system having a glow discharge gap formed by electrodes. A fluid to be sensed may be brought into the vicinity of a discharge at the gap. Light from the discharge may be coupled to a spectrum analyzer and/or processor for determining properties of the fluid. A coupling may include a waveguide proximate to the discharge gap. Window cleanliness and electrode electrical isolation may be maintained by the discharge. The optical analyzer may have filters for one or more optical channels to detectors. The detectors may output electrical signals to be processed. The electrodes may be parallel to each other with a light waveguide between them. Or the electrodes may be concentric forming an annular discharge gap. The light waveguide may likewise be concentric to one or more electrodes. The waveguide may be one or more optical fibers, or tubular.