Abstract: A device for detecting properties of a web of material has a crossbar extending across the web of material. An infrared spectrometer having a holographic grating is provided an has an input side and an output side. Infrared detectors are arranged at the output side of the infrared spectrometer and are formed by a detector matrix having n lines and m rows of infrared sensitive individual sensors. A plurality of optical waveguides are provided, each waveguide having an entrance area and an exit area. The entrance area is fastened to said crossbar, located in vicinity of the surface of the web of material and is oriented towards said surface. The exit areas of the optical waveguides are connected to the input side of the infrared spectrometer.

Abstract: The invention relates to a method and a measuring arrangement for determining roughness of paper or paperboard. The paper or paperboard surface is illuminated with collimated light substantially parallel with the normal of the paper or paperboard surface. An image is produced from the paper or paperboard surface by means of reflected optical radiation. The reflected optical radiation is used for producing an image of the paper or paperboard surface onto the pixels of the camera's detector surface, each of the pixels imaging an area in the order of micrometers of the paper or paperboard surface. An aperture provided in front of the camera is used for adjusting the depth of focus of the image, which affects the measurement of roughness. Roughness of paper or paperboard is measured on the basis of the intensity of the pixels on the camera's detector surface.

Abstract: An industrial process material flow within an industrial process is controlled by a process control loop that includes a process controller, a field device controller and a field device in the process as well as process variable feedback from the process to the process controller. Both the process controller and the field device controller, such as a valve controller, are fine-tuned so that their interaction is taken into account and controller parameters, which provide an optimal control loop performance are found. This results in a significant improvement in the control loop performance, i.e., in a lower process variability, as compared with the traditional tuning method, which does not take into account the interaction between the two controllers.

Abstract: A method and an apparatus for measuring properties of a paper web, whereby at least one property of the paper web is measured at least at two locations in the cross direction of the paper web simultaneously. Adjacent measuring devices are calibrated by traversing a reference sample in the cross direction such that the reference sample is impinged by the measuring beam from each of the measuring devices.

Abstract: The invention relates to a method and measuring apparatus for measuring freeness. Freeness is measured with the help of an automatic data processing apparatus (30) so that the flow rate of a liquid draining from a measuring chamber (10) is measured using the measuring apparatus (12) until the flow rate is equal to or lower than a predefined flow rate.