Abstract: An object of the present invention is to provide an optical transmission system capable of controlling a transmission capacity and a signal processing load of a MIMO equalizer, without depending on the number of propagation modes of the optical fiber.

Abstract: The purpose of the present invention is to provide an optical fiber amplifier capable of seamlessly and collectively amplifying optical signals in a plurality of bands. In order to achieve the aforementioned purpose, the optical fiber amplifier according to the present invention is the optical fiber amplifier that amplifies multiple wavelength bands, and in cross-section, one signal light primary propagation region, and a doped region where rare-earth ions have been added, wherein the doped region includes the rare-earth-doped optical fiber existing other than the propagation region.

Abstract: A twin wire former of a paper machine can perform dewatering gently and symmetrically on the front and back sides of the wet paper, thereby producing paper with good yield and excellent front/back similarity. The twin wire former includes the loops of two wires, and first, second and third dewaterers, having large radii of curvature and disposed inside one and the other of the loops of the wires sequentially alternately between a point where a raw material jet alights on the wires and a couch roll, and the wire-run over this section is diagonal. The first and third dewaterers are disposed inside the loop of the wire and the second dewaterer is disposed inside the loop of the wire. This second dewaterer is pivotable about a point in the vicinity of its rear end, and the couch roll is a solid roll. This couch roll, a transfer suction box and the third dewaterer are mounted on a swing arm and can be pivoted for wire installation.

Abstract: A dewatering instrument of a twin-wire former allows the angles at which the wires are wrapped around the dewatering blades to be adjusted even during operation so that pulsating pressure applied to the paper stock may be set appropriately according to the prevailing paper making condition. The respective dewatering blades of the dewatering instrument are supported by two support bodies, the first one of which is fixed and pivotably supports the blade, and the second one of which is movable to pivot the blade about the first. For example, the second support body may be a flexible tube which is inflatable and deflatable. When the blade is pivoted, the attitude of the land of the blade is changed so that the wrap angles of the wires with respect to the land of the dewatering blade are adjusted.

Abstract: In producing a foam insulated electric wire having an insulating layer made of a polyolefin foam, a foaming agent is employed, which is a liquid mixture of at least two kinds of compounds selected from the group consisting of ethers, esters, ketones and saturated hydrocarbons having boiling points of 100.degree. C. or below, or a liquid mixture of at least one kind of compound selected from the group consisting of ethers, esters, ketones and saturated hydrocarbons having boiling points of 100.degree. C. or below and at least one kind of liquid compound selected from the group consisting of ethers, esters, ketones, saturated hydrocarbons and alcohols having boiling points higher than 100.degree. C. but not exceeding 150.degree. C. Thus, a foam insulating layer having a high cell content and a low deformation ratio become available. Since the foam insulating layer has a high cell content and a low deformation ratio, the foam insulating layer, if reduced in diameter, is hardly squeezed.

Abstract: In a twin-wire former in a paper machine, an operation of a hybrid former mode and that of a gap former mode are conducted, and papers of quality conforming to the kind of papers can be made in a wide range of basis weight with regard to multiple kinds of papers.In the twin-wire former, a forming roll, which guides a top wire so that it can approach to a bottom wire to pinch the stock of paper and run approximately horizontally, is made adjustable in an up and down direction.Upper surfaces of blades of a forming board and a forming shoe provided inside a loop of the bottom wire, are upwardly convex so that dewatering can be effected mainly downward.