摘要:
A method includes acquiring a chemical sample and modulating the chemical sample at a frequency greater than a drift frequency of a sensor. The method also includes determining at least one of a presence and a concentration of the analyte within the modulated chemical sample using the sensor. Modulating the chemical sample could include alternately absorbing at least some of the analyte into a sorbent material and releasing at least some of the analyte from the sorbent material. Modulating the chemical sample could also include heating the sorbent material, absorbing part of the analyte into the sorbent material, and passing a remaining portion of the analyte into the sensor. Modulating the chemical sample could further include stopping the heating of the sorbent material, releasing the part of the analyte from the sorbent material, and passing the sample with the released part of the analyte into the sensor.
摘要:
A method includes acquiring a chemical sample and modulating the chemical sample at a frequency greater than a drift frequency of a sensor. The method also includes determining at least one of a presence and a concentration of the analyte within the modulated chemical sample using the sensor. Modulating the chemical sample could include alternately absorbing at least some of the analyte into a sorbent material and releasing at least some of the analyte from the sorbent material. Modulating the chemical sample could also include heating the sorbent material, absorbing part of the analyte into the sorbent material, and passing a remaining portion of the analyte into the sensor. Modulating the chemical sample could further include stopping the heating of the sorbent material, releasing the part of the analyte from the sorbent material, and passing the sample with the released part of the analyte into the sensor.
摘要:
Sensor apparatus includes a housing, a probe mounted to the housing, the probe including an elongate first part and a helical coil second part conductively coupled to each in series with first and second terminals at opposite ends thereof, the probe to be inserted into an exhaust stream in an exhaust corridor; and a circuit coupled to the first and second terminals of the sensor probe, to selectively operate the probe as a temperature sensor in a first mode and as a PM sensor in a second mode.
摘要:
A catalyst system that may regenerate while removing pollutants from an exhaust gas of an engine. The system may have a converter with multiple segments of chambers. At least one of the chambers may be regenerated while the remaining chambers are removing pollutants from the exhaust. The chambers may be rotated in turn for one-at-a-time regeneration. More than one chamber may be regenerated at a time to remove collected pollutants. The system may have plumbing and valves, and possibly mechanical movement of the chambers, within the system to effect the changing of a chamber for regeneration. The chambers connected to the exhaust may be in series or parallel. A particulate matter filter may be connected to the system, and it also may be regenerated to remove collected matter.
摘要:
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. The indications of instantaneous emissions can be used to effect real-time adjustments in engine control, and can be logged for maintenance purposes.
摘要:
A system for controlling fuel to an engine to minimize emissions in an exhaust of the engine. There may be a controller connected to an actuator, for example a fuel control actuator, of the engine and to emissions sensors, such as an NOx and/or PM sensor, proximate to an exhaust output of the engine. The controller, for example a speed controller, may have an input connected to an output of a pedal or desired speed setting mechanism. A speed sensor at a power output of the engine may be connected to an input of the controller.
摘要:
An acoustic wave sensor system for monitoring the etch rate or etch ability of a selective material has an acoustic wave sensing device having a piezoelectric substrate and at least one electrode coupled to the substrate for generating a propagating acoustic wave and for detecting changes in frequency or other propagation characteristics of the acoustic wave. A selective material is disposed on the substrate. Changes in propagation characteristics of the wave caused by etching of the selective material by an etchant can be analyzed to evaluate the etching rate or etch ability of the selective material. The sensing system can have a wireless sensing device which device is mountable in an oil filter system for monitoring the corrosion of the engine. The sensing device can be configured as BAW, SH-SAW, SH-APM, FPM devices or other acoustic wave devices.
摘要:
An occupancy sensor having a primary infrared radiation sensor and a secondary infrared radiation sensor in an integrated vacuum package having a window that provides separate fields of view to the sensors, respectively. The primary sensor is for monitoring occupancy of a selected space. The secondary sensor is for monitoring the background radiation of the space. Signals from the primary and secondary sensors are electronically processed and compared, and the occupancy level of the selected space is determined. Temperature and visible light sensors may also be incorporated. Sensor information is used to control temperature, ventilation, lighting and other parameters of the selected space.
摘要:
A capacitance-based moisture sensor may include a sleeve having an internal cavity, a container filled with soil or other material inserted into the internal cavity, and a pair of ring-shaped conductive bands around the exterior of the sleeve forming a capacitor and providing a frequency output. The rings positioned around a perimeter of the sleeve may be connected to a fixed inductor to form an oscillator with a variable frequency output. The sensor may be calibrated from the frequency output for each of a plurality of substances, measuring the volumetric water content for saturation of the material, and determining at least one fitting constant in an equation wherein volumetric water content is a function of the frequency output and a plurality of fitting constants.
摘要:
A system for controlling fuel to an engine to minimize emissions in an exhaust of the engine. There may be a controller connected to an actuator, for example a fuel control actuator, of the engine and to emissions sensors, such as an NOx and/or PM sensor, proximate to an exhaust output of the engine. The controller, for example a speed controller, may have an input connected to an output of a pedal or desired speed setting mechanism. A speed sensor at a power output of the engine may be connected to an input of the controller.