Abstract: The objective of the invention is to offer a Reed-Solomon decoding device in which it is possible to perform decoding calculations at high speed without greatly increasing the circuit scale.

Abstract: In manufacturing a rolling bearing, at least one component of an inner ring, an outer ring, and a rolling element is manufactured from an alloy steel comprising 0.05 weight %-0.5 weight % carbon, 0.5 weight %-18 weight % chromium, 1.5 weight % or less silicon, 5 weight % or less molybdenum, 4.0 weight % or less vanadium, 4 weight % or less nickel, and 8 weight % or less tungsten, by subjecting the alloy steel to carburizing, hardening and tempering. The carburizing is carried out by vacuum carburization. In the vacuum carburization, carburizing and diffusion are carried out by introducing an acetylene-based carburizing gas in a hot atmosphere under reduced pressure, followed by hardening and tempering. The use of the vacuum carburization enables carburization with the chromium (Cr) content being 3.0 weight % or more, and even up to 18 weight %, which was difficult to achieve with the conventional gas carburization (pre-oxidation+gas carburizing).

Abstract: At least one of the components of a rolling member used in a manner in which it is rolled or slid with a mated member is made of carbon steel containing 0.8%-0.9% by weight of C, 0.1%-0.7% by weight of Si, 0.5%-1.1% by weight of Mn, and 0.1%-0.6% by weight of Cr and Fe substantially in the remaining part, wherein an ideal critical diameter DI value calculated from the compositions is 1.5-4.0, and the retained austenite amount after hardened heat treatment is 8%-22% by volume. The value DI is determined by the following equation:DI=(0.311.times.C %.sup.0.498).times.(0.7.times.Si %+1).times.(3.33.times.Mn %+1).times.(2.16.times.

Abstract: A rolling bearing includes a rolling element made of a steel containing 0.9 to 1.1 wt. % C, 0.1 to 0.5 wt. % Si, 0.2 to 0.8 wt. % Mn, 1.0 to 1.8 wt. % Cr, with the balance being Fe and inevitable impurities. In the rolling bearing at least the surface of the rolling element includes carbides having an area fraction of 5% to 15%; of these carbides, carbides having an averaged particle diameter of 0.5 .mu.m or more share 50% or more of the area fraction of all the carbides; and of the carbides, carbides having an averaged particle diameter of 1 .mu.m or more share 2% or less of the area fraction of all the carbides; and wherein the rolling element has at least a Vickers surface hardness HV of 750 to 900.

Abstract: A transmission system is disclosed which permits the receiving end to demodulate multi-valued modulated symbols successfully under fading conditions and reduces the amount of transmitted reference data to improve data transmission efficiency. At the transmitting end, a multiplexing section, a modulating section, and a transmitting section are provided. In transmitting an OFDM transmission frame, null symbols and reference symbols are placed in the beginning portion of the frame and QPSK symbols are placed in an information symbol data region in the frame with equal spacings in time and frequency. At the receiving end, a receiving section, a demodulation section, an equalizing section, and a demultiplexing section are provided. An error detector detects amplitude and phase errors of each carrier from the reference symbols, and a variation detector detects variations in the amplitude and phase of a received signal from the QPSK symbols.

Abstract: This invention improves the frequency acquisition range and the resistance to multipath interference. In a digital signal transmission system using OFDM, on the transmission side, some or all of a plurality of equidistant carrier positions are treated as reference carrier positions. The actual transmitted carriers are arranged in a predetermined pattern non-equidistant to the frequency carrier positions to form an OFDM symbol. This OFDM symbol is periodically transmitted as frequency reference symbols. On the reception side, the carrier arrangement pattern of the frequency reference symbols is detected, a carrier frequency offset is detected from the detected pattern offset, and the carrier frequency is compensated based on the frequency offset.

Abstract: A rolling bearing has components of an inner race, an outer race and rolling elements, one of the components being formed of an alloy steel containing 0.1-1.0 wt % of C, 0.1-1.5 wt % of Si, 0.1-1.5 wt % of Mn and 0.1-3.0 wt % of Cr, the alloy steel being carbonitrided and then ground to form a surface layer having a carbon and a nitrogen concentration of 0.6-1.5 wt % and 0.05-0.9 wt %, respectively. The surface layer has an appropriate amount of retained austenite .gamma..sub.R and is sufficiently hard to insure long life even under lubrication in the presence of foreign matter. By optimizing the choice of constituent materials, processing methods and heat treatments for each of the rolling elements and the inner and outer races, rolling bearings that have high performance can be produced at low cost.

Abstract: In a method and an apparatus for correcting a hardening deformation of an annular element made out of steel, during the cooling stage of hardening, the annular element which still has an austenitic structure is subjected to working on either the outside or inside diameter, with the degree of working being 0.05-1.0% if it is on the outside diameter with the annular element being pressed into a mold, and 0.5-3.0% if the working is on the inside diameter. Thus the deformation that develops in annular steel elements due to heat treatments is effectively corrected to yield completely round, strain-free or deformation-free annular elements.

Abstract: A digital data processing apparatus capable of reducing a circuit scale without deteriorating error-correcting capability, and capable of reducing the bit number of a branch metric calculating circuit. The apparatus includes: a region determining portion which determines an optimal bit number corresponding to the number of representative symbol groups; a delaying portion which delays an output from the region determining portion for as long as a coded bit is decoded by a Viterbi decoding portion; and a decoding portion which inputs and decodes an output from the delaying portion and a coded bit that is decoded by the Viterbi decoding portion so as to be decoded, and which outputs the uncoded bit.

Abstract: An object of this invention is to provide a rolling bearing having an inner race which can be used under a high fitting stress over 130 MPa, and can be processed more quickly than the conventional one. In a rolling bearing, according to the present invention, including an inner race which is used with a fitting stress applied between bore of said inner race and shaft, the inner race is formed by an alloy steel whose carbon content is ranged from 0.3 to 0.7% by weight, the inner race is subjected to a carburizing or carbonitriding treatment, and the carbon content (C.sub.1) of the surface layer of the raceway track of the inner race is at most 1.3% by weight, and the inner race has the difference (.DELTA.C=C.sub.1 -C.sub.2) between the carbon content (C.sub.1) of the surface layer and the carbon content (C.sub.2) of the core of the inner race being at least 0.4% by weight. When the amount of residual austenite of the inner race is 4.

Abstract: An object of this invention is to provide a rolling bearing in which, as for the rolling elements, it is unnecessary to employ a high level heat treatment such as carburizing or carbonitriding which requires a long period of time to achieve, and which is sufficiently long in service life even when used with a lubricant containing foreign matters. In a rolling bearing, the amount of residual austenite (.gamma..sub.R vol %) in the surface layer of at least one of the inner and outer races is in a range of 25 to 40 vol %, and the surface hardness (Hv) thereof meets the following condition:-4.7.times.(.gamma..sub.R vol %)+900.ltoreq.Hv.ltoreq.-4.7.times.(.gamma..sub.R vol %)+1000and the hardness of the rolling elements combined with the inner and outer races is higher by H.sub.R C 1 to 2 than that of the one of the inner and outer races.

Abstract: In order to provide a ball-and-roller bearing that has a longer life and which exhibits higher reliability than the prior art products not only under lubrication in the presence of foreign matter but also under lubrication in clean conditions, according to the present invention, a bearing material that contains 0.2 to 1.0 wt % of carbon and at least 1 wt % in total of one or more elements selected from among chromium, molybdenum and vanadium is subjected to a carbonitriding treatment and a hardening heat treatment to make an alloy steel in which the area ratio of carbonitrides present in the surface layer of said bearing material per unit area is adjusted to be at least 10%, a maximum grain size of carbonitrides present in said surface layer being no more than 3 .mu.m, the content of retained austenite (.gamma..sub.R) in said surface layer being 25 to 45 vol %, and said surface layer having a surface hardness of at least 750 Hv.

Abstract: A long-life bearing steel and a long-life rolling bearing made of the steel are disclosed. In the steel, the number of oxide or oxide-based inclusion particles in a given unit area A of 160 mm.sup.3 with an average particle size of 3 to 30 .mu.m is 80 or less and an abundance of oxide or oxide-base inclusion particles with 10 .mu.m or more average particle size to oxide or oxide-based inclusion particles having an average particle size of 3 to 30 .mu.m is below 2%. An electron beam melting extraction evaluation method irradiating electron beam under the following condition guarantees the cleanness of the steel: 350 V+100.ltoreq.J.ltoreq.700 V+200, wherein J represents electric charge power in W provided by electron beam and V represents a sample volume in cm.sup.3.

Abstract: A ball-and-roller bearing provided with a bearing ring and rolling element has the surface hardness of at least one of the bearing ring and rolling element of Hv 900 or more and the minimal compression residual stress of 100 kgf/mm.sup.2 or more in the depth from the surface of the bearing ring and/or rolling element to the depth equivalent to a 2% of the mean diameter of the rolling element and at the same time, the bearing is closely sealed to prevent any foreign particles from being ingressed thereinto, thus making possible a significant improvement of its longevity.

Abstract: A rolling bearing having bearing rings and rolling members wherein at least one of the bearing rings and the rolling members essentially consists of an alloy steel which contains carbide-forming elements. The bearing rings and the rolling members are subjected to carburizing or carbo-nitriding and then hardening to form a rolling surface layer. The content of retained austenite (.gamma..sub.R vol %) in the rolling surface layer is from 20 to 45% by volume and the hardness (Hv) of the rolling surface layer reinforced by dispersion of fine carbides or carbonitrides with an average grain size of from 0.5 to 1.5 .mu.m with regard to the content of the retained austenite (.gamma..sub.R vol %) is within the range of:-4.7.times.(.gamma..sub.R vol %)+920.ltoreq.Hv.ltoreq.-4.7.times.(.gamma..sub.R vol %)+1020.

Abstract: A polyoxymethylene multi-copolymer obtainable by copolymerizing(a) trioxane,(b) at least one cyclic ether or formal compound chosen from the group of ethylene oxide, 1,3-dioxolane, 1,3-dioxepane, 1,3,5-trioxepane and 1,3,6-trioxocane, and(c) at least one compound chosen from the group of glycidyl phenyl ether, styrene oxide and glycidyl naphthyl ether,and characterized in that the number average molecular weight of said polyoxymethylene multi-copolymer is from 10,000 to 100,000, that the melting point (Tm) and crystallization temperature (Tc) there of are in a relationship ofTm-Tc<15 (.degree.C.)and that the size of the spherulites is 10 .mu.m or less, or a resin composition comprised of this polyoxymethylene multi-copolymer and a polyoxymethylene resin, is distinguished in crystallinity, mechanical strength and surface appearance and is particularly suited for faster cycle molding.