Abstract: A high-strength cold-rolled steel sheet includes, by mass %, C: 0.10% to 0.40%, Mn: 0.5% to 4.0%, Si: 0.005% to 2.5%, Al: 0.005% to 2.5%, Cr: 0% to 1.0%, and a balance of iron and inevitable impurities, in which an amount of P is limited to 0.05% or less, an amount of S is limited to 0.02% or less, an amount of N is limited to 0.006% or less, the microstructure includes 2% to 30% of retained austenite by area percentage, martensite is limited to 20% or less by area percentage in the microstructure, an average particle size of cementite is 0.01 ?m to 1 ?m, and 30% to 100% of the cementite has an aspect ratio of 1 to 3.

Abstract: A steel sheet, including: as chemical components, by mass %, 0.05% to 0.35% of C; 0.05% to 2.0% of Si; 0.8% to 3.0% of Mn; 0.01% to 2.0% of Al; equal to or less than 0.1% of P; equal to or less than 0.05% of S; equal to or less than 0.01% of N; and the balance including iron and inevitable impurities, wherein an area ratio of equal to or higher than 50% of a total of a ferrite phase, a bainite phase, and a tempered martensite phase is contained, an area ratio of equal to or higher than 3% of a retained austenite phase is contained, and crystal grains of the retained austenite phase having a number ratio of equal to or higher than 50% satisfy Expression 1, assuming carbon concentration at a position of center of gravity is Cgc and a carbon concentration at a grain boundary is Cgb.

Abstract: When a disk on which signals are recorded in a number of separate tracks is inserted into reproducing apparatus, reproduction signals from a head are first obtained and tracking is performed for each track to determine the position of the head that gives the strongest reproduced signal from each such track. The tracking positions that respectively give the strongest signals from the several tracks are stored in a memory. When it is later desired to reproduce signals from a particular track, the head is positioned on the basis of the content of the memory.

Abstract: Audio signals are recorded on recording tracks of a disk shaped recording medium in a predetermined schedule for making establishment of an associated track information table easier and allowing after recording of audio signals with respect to each video signal. In addition, selective or entire erasure of video signals and associated audio signals is automatically performed when one of the recording tracks recording one of the video signals or the associated audio signals is ordered to be erased.

Abstract: Audio signals are recorded on recording tracks of a disk shaped recording medium in a predetermined schedule for making establishment of an associated track information table easier and allowing after recording of audio signals with respect to each video signal. In addition, selective or entire erasure of video signals and associated audio signals is automatically performed when one of the recording tracks recording one of the video signals or the associated audio signals is ordered to be erased.