Abstract: Apparatus for applying noise-reducing elements to a tyre for vehicle wheels that has a radially inner surface with a service area and a circumferential dimension. The apparatus determines the position in circumferential direction of the service area, determines the position in circumferential direction of a target area on the radially inner surface of the tyre based on the position in circumferential direction of the service area, and applies a noise-reducing element the target area. The position in circumferential direction of the service area is determined by circumferentially inspecting the radially inner surface of the tyre starting from a reference position, detecting the angular position of the service area with respect to the reference position and determining the position in circumferential direction of the service area based on the angular position and on the circumferential dimension of the radially inner surface of the tyre.

Abstract: A carcass sleeve is situated in a radially external position with respect to a toroidal forming drum, arranged in a first radially contracted operative condition. The carcass sleeve is shaped according to a toroidal configuration while the forming drum is positioned inside the carcass sleeve. During shaping of the carcass sleeve, the forming drum is radially expanded up to a second radially expanded operative condition. Upon completed shaping, the carcass sleeve is coupled to the forming drum in the second operative condition. The forming drum, coupled to the shaped carcass sleeve, is arranged in proximity to at least one device for building at least one belt layer at a radially external position relative to the shaped carcass sleeve.

Abstract: An optical fiber unit having a sheath and a plurality of optical fiber elements loosely housed in the sheath. The sheath is coated with particles of an adherence reducing substance and has a radial thickness that is not substantially greater than 0.3 mm. The coating of adherence reducing particles is applied as a liquid coating. The liquid coating is a dispersion of the particles and heat is applied to evaporate the liquid content of the liquid coating to produce a dry coating of particles on the sheath.

Abstract: An optical fiber filter includes an optical fiber, a pair of first coupling regions, and a phase-shift region. The optical fiber includes a core and a cladding. An optical signal can pass through the optical fiber. The first coupling regions are formed in the optical fiber, at a predefined mutual distance, for producing power transfer between first and second propagation modes of the optical signal. The phase-shift region is defined by a section of the optical fiber, disposed between the first coupling regions, for producing a phase shift between the first and second propagation modes of the optical signal. In the first coupling regions, the optical fiber includes, in cross-section, an asymmetrical refractive index profile. A related optical fiber filtering device, optical fiber, process for producing an optical filter, optical amplifier, optical telecommunications system, optical fiber modal coupler, and method for filtering an optical signal are also disclosed.

Abstract: An optical cable for telecommunications having an optical core and a plurality of protecting and reinforcing elements or avers placed around the optical core. The optical core has a central reinforcing element, a polymer layer, a plurality of optical fibers incorporated in the polymer layer and a thin sheath which covers the polymer layer. The optical fibers have an alternating spin about their own axes with a maximum value of at least 4 twists per meter, and a core having a mean ellipticity in the range of 0.25 to 0.55, in such a way that the effects of birefringence of the fibers caused by the cabling process are significantly reduced.

Abstract: In order to reduce the AC losses in a superconducting conductor element subjected to an external magnetic field and through which a current flows, tapes of superconducting material of each layer are wound at such a mutual distance that the gap between the superconducting material of adjacent tapes is not smaller than a predetermined minimum value. These elements are particularly useful in three-phase warm dielectric superconducting cables.

Abstract: An optical fiber transmission link has a first optical fiber with a high effective area coupled to a second, downstream optical fiber with a low effective area. The downstream fiber has non-zero dispersion and low dispersion slope. Characteristics of the upstream fiber permit the launching of high power channels in a wavelength division multiplexing, and characteristics of the downstream fiber enable Raman amplification along that fiber to extend the transmission distance before a need for discrete amplification. The downstream fiber has a non-zero dispersion in the C-band wavelengths and a low dispersion slope and has low attenuation at the signal and pump wavelengths. Refractive-index profiles include variations of W-type fibers that may include outer rings of positive or negative index. Pumping of the downstream fiber may occur either co-directionally to the signals, counter-directionally to the signals, or in both directions.

Abstract: Electrical cable particularly for high voltage direct current transmission having at least once conductor and at least one extruded insulating coating layer of a polymeric composition. The polymeric composition is a polyethylene modified with at least one compound of formula (I): in which R represents H or CH3; R1 represents a linear or branched, preferably linear, C1-C8 alkylene group; R2 represents OH; a group OR3 in which R3 represents a linear or branched C1-C4 alkyl group, a group NR4R5 in which R4 and R5, which may be identical or different, represent H, or a linear or branched C1-C4 alkyl group, and related insulating composition.

Abstract: A network for distributing signals to a plurality of user having a distribution unit and a plurality of optical cables adapted to make the distribution unit communicate with the plurality of user equipment. In turn, each optical cable has an optical fibre having a core, a cladding and a predetermined simple refractive index profile ?n(r). Each optical fibre is adapted to guarantee a single-mode propagation at higher wavelengths than about 1260 nm and a few-mode propagation at about 850 nm, and each optical fibre has such refractive index profile ?n(r) as to guarantee macro-bending losses at 1550 nm that are less than about 0.5 dB and an intermodal delay ?? at 850 nm that is less than or equal to, about 1 ns/Km.

Abstract: A method and apparatus for preheating the conductor elements of cables with extruded insulator essentially by forced thermal convection. Particularly for conductors with metal tape reinforcement, such as for example Milliken conductors, where it has been found that the traditional magnetic-induction heating is not satisfactory since the tape reinforcement shields the elements of conductors.

Abstract: A cable with recyclable covering, particularly for transporting or distributing medium or high voltage energy, in which at least one covering layer is based on thermoplastic polymer material comprising a propylene homopolymer or a copolymer of propylene with ethylene or an &agr;-olefin other than propylene in mixture with a dielectric liquid. The cable of the invention possesses superior mechanical and electrical properties, including high dielectric strength, in particular enabling it to be used at high operating temperature.

Abstract: A storable tubular element for covering an electric cable joint which includes a rigid tubular support with a three layer sleeve having an unstretched bore of a size less than the external diameter of the support mounted on the tubular support in radially stretched condition. The element is usable for a group of cables having several different diameters and the properties and thicknesses of the layers are selected so that with storage on the support, the layers do not tear and so that when the sleeve is applied to a joint, the sleeve will apply the desired pressure to the cable even though it has a temporary residual deformation and does not immediately tend to return to its initial unstretched state.

Abstract: An optical telecommunication system including a transmitting station and a receiving station for optical signals, connected with each other by an optical fiber line including optical line amplifiers having a rare-earth-doped active fiber and connected in series, in which the transmitting station includes signal generator for generating signals at several wavelengths, and connections for conveying the signals to a single optical fiber line. The optical signal receiving station includes apparatus for separating the signals. At least one of the optical line amplifiers has dopants, fiber length and pumping power capable of determining, at the input of the receiving station, an optical signal/noise ratio which for the different wavelengths has a difference less than 2 dB, and for each signal is greater than 15 dB.

Abstract: A storable covering element for electric cable joints which includes a tubular support on which a multi-layer sleeve is mounted in radially stretched condition, a cable joint with such a sleeve and a sleeve for such use. The sleeve has an inner layer of cross-linked polymeric material which has a temporary residual deformation after storage for at least 24 months at room temperature which is less than such deformation of the layers outwardly thereof and preferably has a modulus of elasticity greater than the modulus of elasticity of the layers outwardly thereof. The outer layers are also made of cross-linked polymeric material, and each layer is bonded to the adjacent layer so that the inner layer will pull the outer layers radially inwardly when the sleeve is applied to a cable joint.

Abstract: Connectors for optical cables in ribbon form and a process for making such connectors in which metal plates for the enclosing the cable ends are made by cold, plastic flow forming of grooves in the plates with a punch having ridges produced by a process which produces grooves which hold the positions of the optical fibers between the plates within narrow tolerances. In the process, a punch body with partially formed ridges is mounted on a head rotatable about the axis of the body and movable toward a grinding wheel which is movable in a path perpendicular to the direction of movement of the head toward the grinding wheel. After two opposite passes of the grinding wheel along the side of a ridge, the punch body is rotated 180 degrees, and the side of a corresponding ridge on the opposite side of the punch body axis is ground. The process is repeated with movement of the head toward the grinding wheel, which is measured, until the sides of all ridges are ground.

Abstract: An optical, low-noise amplifier of the active-fiber type, which fiber contains a laser light emitting substance, adapted to be connected to an optical telecommunication fiber and receiving light therefrom at the transmission wavelength. The active fiber is also fed from a light source at a pumping wavelength and has a length corresponding to a partial absorption of the pumping light. Downstream of active fiber, there is a selective mirror device which reflects the light at the pumping wavelength and is transparent to the transmission wavelength light. Preferably, the mirror device consists of an optical demultiplexer adapted to separate the transmission wavelength and the pumping wavelength on two output fibers. A mirror which reflects the pumping wavelength is present at the end of the fiber carrying the pumping wavelength.

Abstract: An optical amplifier (3) in accordance with the invention consists of the assembly of a length of active-core optical fiber (8), single-mode to both pumping and signal optical radiations, and a dichroic coupler (6) which includes two optical fiber lengths (9, 10), both single-mode to pumping and signal optical radiations, coupled to each other over one portion (11) by fusion of the respective claddings and substantial setting in common of the respective cores in the fused portion (11).