Abstract: A method for operating an exhaust-gas treatment device of an internal combustion engine and a device for carrying out the method, in which a reagent, whose pressure is measured by a reagent pressure sensor, is introduced into the exhaust-gas area upstream from the exhaust-gas treatment device. First the reagent pressure is brought to the exhaust-gas pressure which prevails in the exhaust-gas area upstream from the exhaust-gas treatment device. Then the pressure difference between the reagent pressure and the sum of the exhaust-gas pressure and the ambient air pressure is compared to a predefined pressure difference threshold, and if the pressure difference threshold is exceeded an error signal is supplied. The procedure contributes to an exact metering of the reagent through a diagnosis of the reagent pressure sensor.

Abstract: An improved method of forming an intrinsic polarizer, referred to as a K-type polarizer, includes stretching a polymeric film a first stretching step. The polymeric film comprises a hydroxylated linear polymer which is converted after the first stretching step to form dichroic, copolymer polyvinylene blocks aligned in the polymeric film. The polymeric film is stretched in a second stretching step while converting the hydroxylated linear polymer. This method produces an improved K-type polarizer with excellent polarizing and color characteristics. For example, the dichroic ratio is higher than 100, the color shift for light passed through the polarizer in a crossed configuration is low, and the absorption of light in the blue region of the visible spectrum is more than one half of the absorption for light in the middle of the visible spectrum.

Abstract: A method for metering a reagent which an emission control device situated in the exhaust duct of an internal combustion engine requires for removing at least one exhaust gas component from the exhaust gas and a device for executing the method are described. The fluid level of the reagent stored in a reagent tank is measured. The measured change in the fluid level is compared to at least one measure for the change in the fluid level calculated as a function of consumption. An error signal is output when the comparison result exceeds a predefined threshold value. This approach enables reliable information to be provided about the fluid level of the reagent in the reagent tank.

Abstract: A method and a device for controlling an internal combustion engine having a central control unit and a peripheral control unit are described. The central control unit transmits request signals to the peripheral control unit. At least two load circuits receive control signals from the peripheral control unit. The peripheral control unit checks the request signals and/or additional signals for plausibility.

Abstract: A method and a device for controlling an internal combustion engine having a central control unit and a peripheral control unit are described. The central control unit transmits request signals to the peripheral control unit. At least two load circuits receive control signals from the peripheral control unit. The peripheral control unit checks the request signals and/or additional signals for plausibility.