Abstract: This cold-rolled steel sheet has a predetermined chemical composition, in which a metallographic structure of a t/4 portion, which is at a ¼ position of a sheet thickness t from a surface of the cold-rolled steel sheet in a sheet thickness direction has a predetermined structure, and in both an edge portion, which is at a position 50 mm away from an end portion of the cold-rolled steel sheet in a width direction, and a center portion of the cold-rolled steel sheet in the width direction, a metallographic structure of a 20 ?m portion, which is at a position 20 ?m away from the surface in the sheet thickness direction, includes, by volume percentage, ferrite and bainite: 75.0% or more and 100.0% or less in total, and martensite and tempered martensite: 0.0% or more and 25.0% or less in total, an average grain size of the martensite and the tempered martensite in the metallographic structure of the 20 ?m portion is 5.

Abstract: This high-strength cold-rolled steel sheet has a predetermined chemical composition, wherein a microstructure at a ¼ position of a sheet thickness from a surface includes predetermined ranges of volume percentages of tempered martensite, residual austenite, ferrite and bainite, and martensite, wherein a microstructure at a position 25 ?m from the surface includes, predetermined ranges of volume percentage of ferrite and bainite, and martensite and tempered martensite, wherein in the position 25 ?m from the surface, an average grain size of the martensite and the tempered martensite is 5.0 ?m or less, a tensile strength is 1,310 MPa or more, and a uniform elongation is 5.0% or more, and R/t is 5.0 or less, the R/t being a ratio of a limit bend radius R in 90° V-bending to a sheet thickness t.

Abstract: This high-strength cold-rolled steel sheet has a predetermined chemical composition, a microstructure at a ¼ position of a sheet thickness from a surface includes, by a volume percentage, 70.0% or more of tempered martensite, more than 3.0% and less than 10.0% of residual austenite, a total of 25.0% or less of ferrite and bainite, and 5.0% or less of martensite, a microstructure at a position 25 ?m from the surface includes, by the volume percentage, a total of 70% or more of ferrite and bainite and a total of 30% or less of martensite and tempered martensite, in the position 25 ?m from the surface, an average grain size of the martensite and the tempered martensite is 5.0 ?m or less, a tensile strength is 1,310 MPa or more, a uniform elongation is 5.0% or more, and Rh is 5.0 or less, the Rh/t being a ratio of a limit bend radius R in 90° V-bending to a sheet thickness t.

Abstract: The invention provides a waveform information display apparatus, wherein the property of waveform data is grasped by the light of nature. Specifically, digital waveform data stored in a memory is split into a plurality of time segments, and compressed display data is generated in each of the time segments. A waveform is displayed on the screen by the compressed display data. Then, a property specified for the waveform is extracted from the digital waveform data in each of the time segments, and a value expressing the specified property in the time segment is obtained on the basis of the extracted property. Further, a waveform display portion in each of the time segments displayed on the screen on the basis of the compressed display data in each of the time segments is displayed in a state wherein the obtained value expressing the property is reflected on the waveform display portion.

Abstract: The invention provides a waveform information display apparatus, wherein the property of waveform data is grasped by the light of nature. Specifically, digital waveform data stored in a memory is split into a plurality of time segments, and compressed display data is generated in each of the time segments. A waveform is displayed on the screen by the compressed display data. Then, a property specified for the waveform is extracted from the digital waveform data in each of the time segments, and a value expressing the specified property in the time segment is obtained on the basis of the extracted property. Further, a waveform display portion in each of the time segments displayed on the screen on the basis of the compressed display data in each of the time segments is displayed in a state wherein the obtained value expressing the property is reflected on the waveform display portion.