Abstract: An oxygen concentration-based exhaust gas recirculation (EGR) flow rate compensation control method may include a model compensation mode, which confirms engine information acquired from an engine system, calculates an intake oxygen concentration by a model intake oxygen mass ratio through a combination of an intake oxygen mass ratio model value and a model exhaust lambda value and an indirect intake oxygen mass ratio through a combination of the intake oxygen mass ratio model value and an exhaust-side measurement lambda value, respectively, and compensates the model intake oxygen mass ratio as a model intake oxygen mass ratio compensation value applying a compensation error relative to the indirect intake oxygen mass ratio by using the model intake oxygen mass ratio as a model intake oxygen mass ratio current value, by a controller.

Abstract: An engine control method for a vehicle is provided. The method includes securing target control values for a plurality of control objects related to an air path in an engine and calculating operation amounts of actuators for the control objects. The operation amounts minimize an objective function including the sum of resultant object components obtained by summing, for a predetermined reference time, squares of a difference between the target control values and prediction model functions for the control objects. The actuators are then driven based on the calculated operation values.

Abstract: An engine control method for a vehicle is provided. The method includes securing target control values for a plurality of control objects related to an air path in an engine and calculating operation amounts of actuators for the control objects. The operation amounts minimize an objective function including the sum of resultant object components obtained by summing, for a predetermined reference time, squares of a difference between the target control values and prediction model functions for the control objects. The actuators are then driven based on the calculated operation values.

Abstract: A method for reducing an exhaust gas of a mild hybrid system may include determining by an electronic control unit (ECU) whether an engine enters a full load region or a partial load region, based on a position of an accelerator pedal, controlling, by the ECU, the operation of an electric supercharger, based on information on an engine rotational frequency, when a vehicle is driven while being accelerated in a state in which the engine enters the full load region, and controlling, by the ECU, the operation of the electric supercharger by determining whether the vehicle is accelerated, based on an incremental slope of the position of the accelerator pedal, when the engine enters the partial load region.

Abstract: An engine control system with a variable turbocharger may include an engine including a cylinder generating power by combustion of a fuel, a variable turbocharger including a turbine rotated by exhaust gas exhausted by the engine, and a compressor rotated in synchronization with the turbine and compressing external air and supplying the compressed air to the cylinder, a vane adjusting flow area of exhaust gas supplied to the turbine, and a controller dividing an operation region of a vehicle into a steady-speed driving region, an acceleration driving region, and a deceleration driving region from a fuel amount supplied to the cylinder and a required torque of the engine, and controlling opening of the vane and an injection timing of fuel injected into the cylinder.

Abstract: A method for reducing an exhaust gas of a mild hybrid system may include determining by an electronic control unit (ECU) whether an engine enters a full load region or a partial load region, based on a position of an accelerator pedal, controlling, by the ECU, the operation of an electric supercharger, based on information on an engine rotational frequency, when a vehicle is driven while being accelerated in a state in which the engine enters the full load region, and controlling, by the ECU, the operation of the electric supercharger by determining whether the vehicle is accelerated, based on an incremental slope of the position of the accelerator pedal, when the engine enters the partial load region.

Abstract: Disclosed are vehicle control method and apparatus with transient driving condition recognition. The method may include: operating an engine; calculating a first determination reference value according to a first target boost pressure and a first actual boost pressure; determining whether a differential value of the first determination reference value over time is equal to or more than a first predetermined reference value; controlling a vehicle according to a previously stored exhaust gas reduction map if it is determined that the differential value of the first determination reference value over time is equal to or more than the first predetermined reference value (transient driving condition); and controlling the vehicle according to a previously stored fuel efficiency improvement map if it is determined that the differential value of the first determination reference value over time is less than the first predetermined reference value (a steady driving condition).

Abstract: An engine control system with a variable turbocharger may include an engine including a cylinder generating power by combustion of a fuel, a variable turbocharger including a turbine rotated by exhaust gas exhausted by the engine, and a compressor rotated in synchronization with the turbine and compressing external air and supplying the compressed air to the cylinder, a vane adjusting flow area of exhaust gas supplied to the turbine, and a controller dividing an operation region of a vehicle into a steady-speed driving region, an acceleration driving region, and a deceleration driving region from a fuel amount supplied to the cylinder and a required torque of the engine, and controlling opening of the vane and an injection timing of fuel injected into the cylinder.

Abstract: A fuel injection mechanism for a diesel engine includes a fuel injector, a driving part connected to the fuel injector for actuating the fuel injector, and a controller electrically connected to the driving part for controlling the driving part.

Abstract: A valve train for a small size diesel engine includes a pair of camshafts rotatively supported by and passing over a top of a cylinder head, one pair of intake and exhaust cams on each camshaft for each cylinder, two intake ports and two exhaust ports formed on the cylinder head over and around a bore center of each cylinder for communicating with the cylinder bore, two intake valves and two exhaust valves installed into the corresponding ports for selectively opening and closing the ports, rocker arms of which one end of each is connected to upper ends of the corresponding valves, and lash adjusters connected to other ends of the corresponding rocker arms for adjusting lash between the rocker arms and the cams, wherein the intake and exhaust ports are arranged in an alternative zigzag fashion.

Abstract: A valve train for a small size diesel engine includes a pair of camshafts rotatively supported by and passing over a top of a cylinder head, one pair of intake and exhaust cams on each camshaft for each cylinder, two intake ports and two exhaust ports formed on the cylinder head over and around a bore center of each cylinder for communicating with the cylinder bore, two intake valves and two exhaust valves installed into the corresponding ports for selectively opening and closing the ports, rocker arms of which one end of each is connected to upper ends of the corresponding valves, and lash adjusters connected to other ends of the corresponding rocker arms for adjusting lash between the rocker arms and the cams, wherein the intake and exhaust ports are arranged in an alternative zigzag fashion.

Abstract: An exhaust pressure control system for a diesel engine includes a device for adjusting exhaust pressure of gas exhausted from an exhaust manifold, and an engine control unit for controlling the device according to an engine operation state. The device includes a rotational valve for opening and closing the exhaust pipe , a motor for rotating the rotational valve according to a signal from the engine control unit, and an encoder for detecting an opening state of the exhaust pipe and transmitting a corresponding signal to the engine control unit.