Abstract: Disclosed is a method, performed by an electronic device, for controlling operation of a wind turbine. The method comprises obtaining wind turbine data associated with the wind turbine. The wind turbine data is indicative of conditions of operation of the wind turbine. The method comprises predicting an amplitude modulation (AM) noise parameter indicative of AM noise within a region at a distance from the wind turbine by applying a machine learning model to the wind turbine data. The method comprises generating, based on the AM noise parameter, control data indicative of a control operation of the wind turbine. The method comprises providing the control data to a controller for controlling the wind turbine in accordance with the control data.

Abstract: The invention relates to a translucent screen comprising a sheet element with a first surface and a second surface substantially parallel with the first surface, wherein the first surface comprises a number of lens facets that combine to form a lens system for paralleling diverging light beams that enter into the sheet element. The invention is characterised in that the lens facets contain a refractive agent in a concentration that exceeds the concentration of refractive agent in that part of the sheet element that is located outside the lens facets; and wherein the refractive index of the refractive agent deviates from the refractive index of the material in which the refractive agent is located.

Abstract: A projection screen assembly including a projection screen having an illuminated rear side and a light dispersing front side for showing an image with substantially homogeneous luminosity over a wide viewing angle. The light dispersing front side includes a plurality of closely positioned, substantially parallel and, in the use position of the screen, vertically extending lens elements including two inclined reflecting lens crests, and an intermediate lens. The projection screen is characterized by first and second reflecting rib lenses having planes of symmetry inclined toward each other or away from each other, respectively, and a third reflecting rib lens having a plane of symmetry which is normal to the plane of the screen. The use of a plurality of lenses that are approximately identical, but having different inclinations, provide enhanced homogenous luminosity.

Abstract: A rear projection screen assembly including a screen that is illuminated from behind by at least two image sources, and that has a front side having light dispersing elements for reception of light beams from the image sources in order to display an image with a mainly homogeneous luminosity over a wide viewing angle. The light dispersing elements are defined by a number of closely positioned, substantially parallel, vertically running lens elements, where the lens elements include a number of triangular lenses arranged in pairs of two, each triangular lens having two side faces and a symmetry plane. The symmetry planes of the two triangular lenses for each pair are symmetrically inclined with respect to each other and to a normal of the plane of the projection screen.

Abstract: In a plate heat exchanger for evaporation of a liquid by means of a heat emitting vapor every second plate interspace forms an evaporation passage (28) and the rest of the plate interspaces form condensation passages (30). Aligned openings (16) in the plates form an inlet channel through the plate heat exchanger for introduction of evaporation liquid into the evaporation passages (28). For enabling use of a large inlet area of each condensation passage (30) and a large outlet area of each evaporation passage (28) the plate heat exchanger is arranged in a container (1), the interior of which is divided in two chambers (6, 7) by the plate heat exchanger itself and a partition (5).

Abstract: In a plate evaporator of the falling film type, every second plate interspace constitutes an evaporation space (28) in which evaporation liquid is distributed across the width of the plates in order to run downwardly on the plates, whereas the rest of the plate interspaces constitute condensation spaces (30) for a heat emitting vapor. The invention concerns a particular arrangement for supplying evaporation liquid to the evaporation spaces (28). According to this arrangement, a distribution chamber (27) is delimited within the uppermost part of each plate interspace constituting an evaporation space (28). This distribution chamber extends across the whole width of the plates and communicates with an inlet channel for liquid, extending through the plate package and formed by aligned openings (16) in the plates. In the upper part of each condensation space (30), several sealing means (25) are arranged horizontally spaced from each other.

Abstract: A transparent rear-projection screen is described where the side facing the projectors has a lens surface for parallelling of the light, and where the front side has vertical upright forerunning lenses to upread the light in a horizontal plane, and where between these lenses there are grooves with a light absorbing material to increase the contrast of the projected picture.

Abstract: A transparent, rear-light projection screen that has lenses on its back side facing the projectors for paralleling light from the projectors. The screen on its front side has upright, forerunning asymmetric cylinder lenses with partially reflecting projections having light-refractive surfaces, facing outwardly from the front side and opposite to the direction from which the paralleled light originates from behind. The projection screen improves the color contrast and increases the projected light when the screen is viewed from a side direction.

Abstract: A transparent rear-light projection screen with V-shaped grooves is described, where the rear side of the screen, i.e. the side turned towards the projector is supplied with outwardly extending, elongate parallel lenses, the focal point of which is congruent with the front plane of the screen which is made up of outwardly extending elongate projections on whose tops the light can emit, and where--between the tops of the projections--there are grooves which are covered with material impenetrable to light, such as black color, for the purpose of increasing the contrast.

Abstract: A transparent rear-projection screen, e.g. for video projection, consisting of three screen elements, of which the rearmost element, which faces the light sources, is a Fresnel lense, and the middle element on its reverse or entrance side is provided with lens profiles for horizontal diffusion of the light, and on its front or exit side are lenses for parallelling the light from various light sources, and in which screen the foremost, visually enhanced screen element has on its reverse or entrance side horizontal, convex, rectilinear lenses, the focal point of which is congruent to the tops of projections provided on the front or exit side of the foremost screen element, and from the surface of which the light is emitted.

Abstract: A rear projection screen consists of a Fresnel lens and a picture-forming screen placed in front of it. The picture-forming screen has vertical backward convex lenses on its back and vertical masking strips on its front and strip-shaped sections situated between the masking strips and opposite the backward convex lenses. Each of these is designed to refract light rays coming from behind so that they are directed towards the strip-shaped sections. In order to increase the picture resolution or definition capability of the screen and to avoid notch sensitivity between the backward convex lenses an intermediate lens is provided between every two of the backward convex lenses.

Abstract: A transparent rear projection screen has a Fresnel lens for paralleling light arriving from behind. In the front surface the screen is provided with grooves which extend in the vertical direction in the position of use of the screen. Each of the side flanks of the grooves adjoins a side part of an adjacent, also vertically extending convex lens. The side flanks of the grooves are totally reflecting to parallelled light arriving from behind in order to increase the deflection in the lateral direction of a part of the light arriving from behind by means of reflection into the adjacent lens. The angle which a side flank forms together with the side part of the adjacent lens is so small that total reflection from the inner surface of the side part of the lense of light which is totally reflected of the side flank in question is avoided. Moreover, between the vertical lenses to which the side flanks adjoin, at least one further lens is arranged.

Abstract: A transparent rear projection screen has a lense system for paralleling light arriving from behind. On the front side of the screen rectilinear lenses extending in the vertical direction in the position of use of the screen are provided the sides of which form a small angle of inclination with respect to the normal to the screen. The sides are totally reflecting to light arriving from behind and between the reflecting lenses further lenses are arranged. In order to compensate for color shading by the projection of differently colored television images upon the rear side of the screen, the tops of the reflecting lenses are so shaped and their totally reflecting sides have such an inclination with respect to the normal to the screen, and moreover have such a width that at the most 80% of the light which from behind enters the reflecting lenses is emitted through the tops of the lenses, and that at least 20% of said entering light is emitted through the sides of the lenses.