A powertrain control unit may be configured to control an engine and identify a first operating condition is expected to fulfill a demand for output with an exhaust stream having a first amount of a pollutant (e.g., NOx, particulate matter), and a second operating condition expected to fulfill the demand with an exhaust stream having a reduced amount of the pollutant as compared to the first amount. The powertrain control unit may receive duty cycle information to control the engine to fulfill the demand per the second operating condition, yielding the reduced amount of pollutant in the exhaust. Duty cycle information may include speed, location, position, rotation, temperature, and/or other information. A vehicle, backhoe, bulldozer, crane, and/or combine harvester may comprise the powertrain control unit and an engine and aftertreatment system. An exhaust aftertreatment system may be remotely activated, which may reduce warmup time associated with emissions mitigation.

Systems and methods for controlling a gasoline urea selective catalytic reductant catalyst are described. In one example, an observer is provided that corrects an estimate of an amount of NH.sub.3 that is stored in a SCR. The amount of NH.sub.3 that is stored in the SCR is a basis for generating additional NH.sub.3 or ceasing generation of NH.sub.3.

Various embodiments of the teachings herein include a method for determining the nitrogen oxide content and/or ammonia content in the exhaust gas of an internal combustion engine with a catalytic converter arranged in an exhaust tract and an exhaust gas sensor downstream of the catalytic converter. In some embodiments, the method comprises: determining an operating state of the internal combustion engine, the operating state indicating either lean operation or rich operation of the internal combustion engine; generating a signal using the exhaust gas sensor; and determining the nitrogen oxide content and/or ammonia content in the exhaust gas at least partially based on the determined operating state of the internal combustion engine and the signal.

A system and approach for catalyst model parameter identification with modeling accomplished by an identification procedure that may incorporate a catalyst parameter identification procedure which may include determination of parameters for a catalyst device, specification of values for parameters and component level identification. Component level identification may be of a thermal model, adsorption and desorption, and chemistry. There may then be system level identification to get a final estimate of catalyst parameters.

An evaporative emissions (EVAP) control system for a vehicle includes a purge pump configured to pump fuel vapor to a direct injection (DI) engine of the vehicle via a vapor line and a purge valve and a hydrocarbon (HC) sensor disposed configured to measure an amount of HC in the fuel vapor. The system also includes a controller configured to detect an HC vapor supply condition indicative of an operating condition of the Di engine where engine vacuum is less than an appropriate level for delivering the fuel vapor to the DI engine via the vapor line; and in response to detecting the HC vapor supply condition, controlling at least one of the purge pump and the purge valve, based on the measured amount of HC, to deliver a desired amount of fuel vapor to the DI engine to decrease particulate matter (PM) produced by the DI engine.

To keep medium purification efficiency at a high level and prevent deterioration of emission performance. An aspect of the present invention includes: a downstream equivalence ratio calculation unit that calculates a catalyst downstream exhaust gas equivalence ratio by using a catalyst statistical model that receives at least a detection value of an air-fuel ratio sensor on an upstream side of a catalyst and outputs a catalyst downstream exhaust gas equivalence ratio; an oxygen output calculation unit that calculates an output value of an oxygen sensor by using an oxygen sensor statistical model that receives the catalyst downstream exhaust gas equivalence ratio and outputs an output value of the oxygen sensor on the downstream side of the catalyst; a downstream equivalence ratio correction unit that corrects the catalyst downstream exhaust gas equivalence ratio calculated by the downstream equivalence ratio calculation unit based on a calculation result of the oxygen output calculation unit and the detection value of the oxygen sensor; and an air-fuel ratio control unit that controls an air-fuel ratio of an air-fuel mixture of an internal combustion engine based on the corrected catalyst downstream exhaust gas equivalence ratio and air-fuel ratio target value.

A method for operating a compression ignition engine includes forming a combustible mixture by mixing generally homogeneously a first fuel and air and introducing this mixture into the at least one cylinder, compressing the combustible mixture with the piston in a compression stroke, injecting a second fuel to the combustible mixture at an injection-time of the second fuel during the compression stroke but before start of combustion, and continuing the compression stroke until combustion starts at those locations in the at least one cylinder where concentration of the second fuel is highest and/or the temperature of the mixture is the highest. Emission of the cylinder and/or mechanical stress of the cylinder caused by the combustion are monitored, and if emissions and/or mechanical stress are above respective predetermined thresholds, individually for the cylinder, the amount and/or the timing of the second fuel injected, and/or temperature of the cylinder charge is changed.

Proposed is a gas heat-pump system capable of supplying recirculation exhaust gas using a motor-driven turbocharger and thus actively controlling an amount of flowing recirculation exhaust gas and pressure thereof.

Systems and methods for controlling a gasoline urea selective catalytic reductant catalyst are described. In one example, an observer is provided that corrects an estimate of an amount of NH.sub.3 that is stored in a SCR. The amount of NH.sub.3 that is stored in the SCR is a basis for generating additional NH.sub.3 or ceasing generation of NH.sub.3.

Methods and systems are provided for reducing emissions during an engine cold start. In one example, a method may include, during emission control device heating, injecting heated air into an exhaust runner of each cylinder of the engine during an exhaust stroke of the corresponding cylinder, after a blowdown exhaust pulse. In this way, an amount of hydrocarbons in feedgas provided to the emission control device prior to the emission control device reaching its light-off temperature may be reduced.