bit density การใช้

• Another wrinkle occurs depending on whether surface bit densities are constant.
• Neither the drive itself, nor the controller logic, nor the physical bit density was changed.
• This is not the case with other schemes such as using constant bit density with a CAV spin rate.
• A later'JB'type cartridge will carry 1 TB since its better coating also permits a higher linear bit density.
• Later optical formats such as the audio CD also employ CLV to maintain both a constant data rate and a constant bit density.
• This type of PUF requires atom-level engineering to clone and is the smallest, highest bit density PUF known to date.
• Akonia Holographics has continued to advance Holographic Data Storage Technology and currently holds the world record bit density of 2.2Terabytes / in2.
• When the bit density is constant, outside tracks have more bits than inside tracks and is generally combined with a CLV spin rate.
• Technically, reformatting a cartridge means increasing its track density ( only ), as the linear bit density is limited by the tape coating.
• The time to access data has not kept up with throughput increases, which themselves have not kept up with growth in bit density and storage capacity.
• By superimposing images of different wavelengths into the same hologram, a Stanford research team was able to achieve a bit density of 35 bit / electron ( approximately 3 Exabytes / in 2 ).
• Also, a physically larger drive ( 3.5 " vs 2.5 " ) will be faster at a given bit density and rotation rate, because the bit rate at the outer edge of the platter ( where the first data is recorded on a newly formatted drive ) will be faster.
• Micromation's first major product was an S-100 bus floppy disk controller card called the " Doubler ", named for its ability to record information on 8 " floppy diskettes at twice the bit density previously available, allowing users to store approximately 256 kilobytes of data on each side of an 8 " diskette instead of 128 kilobytes.
• One striking difference between it and other machines on the market at the time was the fact that the disc spun at different speeds according to where the data was stored, running slower towards the outer edge of the disc in such a way that bit density ( bits per cm passing the head ), rather than rotational speed, was approximately constant.
• This allowed standard floppy disks to hold more data than others at the time, 600 kB on single-and 1.2 MB on double-sided floppies compared with 140-160 kB per side of other machines such as the Apple II and early IBM PC, but disks made at constant bit density were not compatible with machines with standard drives.
• CD-ROM ) standards . ( Note that the Yellow Book standard for CD-ROM only specifies a high-level data format and refers to the Red Book for all physical format and low-level code details, such as track pitch, linear bit density, and bitstream encoding . ) This means they use Eight-to-Fourteen Modulation, CIRC error correction, and, for CD-ROM, the third error correction layer defined in the Yellow Book.
• For example, 50 ns allows about five bits to be operated in a racetrack memory device, resulting in an effective cell size of 20 / 5 = 4 F? easily exceeding the performance-density product of PCM . On the other hand, without sacrificing bit density, the same 20 F?area could fit 2.5 2-bit 8 F?alternative memory cells ( such as resistive RAM ( RRAM ) or spin-torque transfer MRAM ), each of which individually operating much faster ( ~ 10 ns ).