A method for operating a heater system including a resistive heating element having a material with a non-monotonic resistivity vs. temperature profile is provided. The method includes heating the resistive heating element to within a limited temperature range in which the resistive heating element exhibits a negative dR/dT characteristic, operating the resistive heating element within an operating temperature range that at least partially overlaps the limited temperature range, and determining a temperature of the resistive heating element such that the resistive heating element functions as both a heater and a temperature sensor. The resistive heating element can function as a temperature sensor in a temperature range between about 500° C. and about 800° C., and the non-monotonic resistivity vs. temperature profile for the material of the resistive heating element can have a local maximum and a local minimum.

A driving device includes a tubular circulation pipe of the exhaust gas, and at least two flow rate measuring members arranged to measure an exhaust gas flow rate circulating in the tubular circulation pipe. The driving device includes at least one monobloc support, housed in the tubular circulation pipe, and bearing at least two flow rate measuring members among said at least two flow rate measuring members.

A reductant storage system for an internal combustion engine system includes a storage container having a bottom wall, a top wall opposite the bottom wall, an opening extending through the top wall, and a reservoir formed by a hollow interior of the storage container; a filter assembly; and a header assembly. The filter assembly extends through the opening and is configured to seal the opening and includes a filtering material. The header assembly extends through the opening and inside the filter assembly. The header assembly includes: (i) a first sensor configured to measure a quality of the reductant contained within the filter assembly and (ii) a second sensor configured to measure a level of the reductant contained within the filter assembly.

A resistor-assembly includes a substrate, a heater, a resistor-element, and conductive-leads. The substrate is formed of a ceramic-material. The heater heats the resistor-assembly. The resistor-element is formed of an ion-conducting material that overlies the substrate. The conductive-leads are formed of a catalytic-metal that are in communication with a gas and in electrical contact with the resistor-element. The resistor-element is characterized by a resistance-value influenced by an oxygen-presence in the gas when the resistor-element is heated by the heater such that a resistor-temperature is greater than a temperature-threshold.

Gas analyzer and method for measuring nitrogen oxides in an exhaust gas, wherein to measure the nitrogen oxides, ozone is generated from oxygen, the exhaust gas is treated with the ozone generated to convert nitrogen monoxide within the exhaust gas into nitrogen dioxide, the nitrogen dioxide concentration in the treated exhaust gas is measured photometrically using a first light-emitting diode which emits with a central wavelength between 350 nm and 500 nm and output as the nitrogen oxide concentration in the exhaust gas, and the ozone concentration in the treated exhaust gas is measured photometrically using a second light-emitting diode which emits with a central wavelength between 250 nm and 265 nm, where generation of the ozone using the measured ozone concentration as an actual value is regulated to a prespecified setpoint value to enable reliable continuous measurement of nitrogen oxides in exhaust gases with a low outlay on equipment.

An aftertreatment system configured to reduce constituents of an exhaust gas produced by an engine comprises an aftertreatment component and an optical assembly. The optical assembly comprises an optical emitter configured to emit light onto a face of the aftertreatment component, and an optical detector configured to detect light reflected from the face of the aftertreatment component. A controller is configured to determine at least one of an amount of NOx gases or an amount of ammonia on the face of the aftertreatment component based on an optical parameter of the detected light that has reflected from the face of the aftertreatment component.

A radio frequency sensor system comprising a housing defining a resonant cavity. Radio frequency probe(s) in the cavity transmit and/or receive radio frequency signals. A radio frequency control unit is in communication with the radio frequency probe(s) for determining one or more states of the radio frequency sensor system based on changes in the characteristics of the radio frequency signals. A machine learning system is in communication with the radio frequency control unit for identifying and developing transfer functions and calibrations based on the changes in the characteristics of the radio frequency signals and determining the one or more states of the radio frequency sensor system.

A heating system includes at least one electric heater disposed within a fluid flow system and a control device that is configured to determine a temperature of the at least one electric heater based on a model, at least one fluid flow system input, and at least one heater input. The at least one heater input includes at least one physical characteristic of the heating system, the at least one physical characteristic includes at least one of a resistance wire diameter, a heater insulation thickness, a heater sheath thickness, a conductivity, a specific heat and density of the material of the heater, an emissivity of the heater and the fluid flow pathway, and combinations thereof. The control device is configured to provide power to the at least one electric heater based on the temperature of the at least one electric heater.

Systems, methods, assemblies, and components for aftertreatment of an engine can comprise an aftertreatment module including an exhaust enclosure with at least one inlet port to receive exhaust gas, an outlet port to output exhaust gas, a first compartment, and a second compartment; a plurality of particulate filters extending in parallel with each other within the exhaust enclosure such that, for each of the particulate filters, an inlet of the particulate filter is in the first compartment and an outlet of the particulate filter is in the second compartment; and at least one radio frequency (RF) sensor set including an RF transmitter assembly and an RF receiver assembly. The RF transmitter assembly can be provided in the first compartment at the inlet of one of the particulate filters, and the RF receiver assembly can be provided at the outlet of said one particulate filter.

A method for monitoring a concentration of a corrosive gas including at least observing at least one gas fuse, the gas fuse having at least one metal wire, which is configured for breaking due to corrosion if exposed to the corrosive gas in a way that a time-integrated concentration of the corrosive gas exceeds a critical value.