Abstract: Disclosed is a circularly-polarized antenna comprising a flat conducting ground plane, a radiator, and an excitation system disposed between the radiator and the ground plane. The radiator comprises a plurality of conducting segments separated from each other by a first dielectric medium and separated from the ground plane by a second dielectric medium. The plurality of conducting segments are symmetrically disposed about an antenna axis of symmetry orthogonal to the ground plane. The excitation system comprises a flat conducting exciter patch and four excitation sources with phase differences of 0, 90, 180, and 270 degrees. The excitation sources are generated on two orthogonal printed circuit boards.

Abstract: Disclosed is a circularly-polarized antenna comprising a flat conducting ground plane, a radiator, and an excitation system disposed between the radiator and the ground plane. The radiator comprises a plurality of conducting segments separated from each other by a first dielectric medium and separated from the ground plane by a second dielectric medium. The plurality of conducting segments are symmetrically disposed about an antenna axis of symmetry orthogonal to the ground plane. The excitation system comprises a flat conducting exciter patch and four excitation sources with phase differences of 0, 90, 180, and 270 degrees. The excitation sources are generated on two orthogonal printed circuit boards.

Abstract: The invention relates to zirconium-based alloys and methods for manufacturing thereof and may be used in nuclear power engineering. The invention, as claimed, solves the task of obtaining a zirconium-based alloy used for manufacturing fuel rods for the nuclear reactor core, which possess improved engineering and operational properties. The said zirconium-based alloy contains its components in the following weight percent ratio: niobium—0.9-1.1, oxygen—0.05-0.09, zirconium—the rest, and has the structure consisting of alpha-zirconium with oxygen irregularity zones not exceeding 30 nanometers, zirconium sub-oxide of non-stoichiometric composition, and beta-niobium. The inventive method of manufacturing the said alloy includes making stock of zirconium-containing material and niobium pentoxide as oxygen-containing and niobium-containing materials, stock treatment and manufacturing an ingot having the above composition.

Abstract: The invention relates to metal forming and can be used for forging billets and blanks by means of hydraulic forging presses. The inventive device comprises two holders for top and lower hammers and two holders for side hammers which are cinematically connected thereto. Each top and lower hammer is provided with two working surfaces separated by a recess in which the working surfaces of the side hammers penetrate. At least one adjusting plate is arranged between the lower hammer and the holder thereof. Said lower hammer is fixed to the holder by two L-shaped clamps which are pressed by the inclined faces thereof against the inclined faces of the lower hammer holder and by the wavy faces thereof against two friction plates which are made, for example of copper and fixed to the side surfaces on the lower hammer. Pins which are fixed in the lower hammer pass through the holes of the adjusting plates and penetrate into the holes of the lower hammer holder.

Abstract: A spinneret precluding the possibility for its material to be stuck to a cutting tool in the course of making a calibrated orifice of a small diameter and ideal as to its form, which will contribute to prolonging the service life of such a spinneret, getting a stable method of forming and maintaining good quality of obtained threads and fibers without impairing the corrosion resistance of the spinneret. The objective is achieved owing to the fact that the spinneret is made of a zirconium alloy containing, in wt. %: niobium ?0.05-1.1 oxygen 0.001-0.2 nitrogen 0.001-0.006 silicon 0.001-0.02 iron 0.001-0.05 molybdenum 0.001-0.005 impurities 0.005-0.26 zirconium the rest. The service life of the resultant spinneret may be increased by 8-27%, the stability of the forming method and quality of threads and fibers are increased.

Abstract: Compact antenna systems for reducing the reception of multipath signals are disclosed. An exemplary antenna system comprises a ground plane, a receiving antenna disposed above the ground plane and providing an output signal of the antenna system, and a passive antenna disposed below the ground plane.

Abstract: Compact antenna systems for reducing the reception of multipath signals are disclosed. An exemplary antenna system comprises a ground plane, a receiving antenna disposed above the ground plane and providing an output signal of the antenna system, and a passive antenna disposed below the ground plane.