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IBM 3850
The IBM 3850 Mass Storage System (MSS) was an online tape library used to hold large amounts of infrequently accessed data. It was one of the earliest examples of nearline storage. History Starting in the late-1960s IBM's lab in Boulder, Colorado began development of a low-cost mass storage system based on magnetic tape cartridges. The tapes would be accessed automatically by a robot (known as an ''accessor'') and fed into a reader/writer unit that could work on several tapes at the same time. Originally the system was going to be used as a directly attached memory device, but as the speed of computers grew in relation to the storage, the product was re-purposed as an automated system that would offload little-used data from hard disk systems. Known internally as ''Comanche'' while under development, IBM management found a number of niche uses for the concept, and announced it officially as the IBM 3850 on October 9, 1974. After more than a decade (comparable to the IBM 2321 D ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Online
In computer technology and telecommunications, online indicates a state of connectivity, and offline indicates a disconnected state. In modern terminology, this usually refers to an Internet connection, but (especially when expressed as "on line" or "on the line") could refer to any piece of equipment or functional unit that is connected to a larger system. Being online means that the equipment or subsystem is connected, or that it is ready for use. "Online" has come to describe activities and concepts that take place on the Internet, such as online identity, online predator and online shop. A similar meaning is also given by the prefixes cyberspace, cyber and e, as in words ''cyberspace'', ''cybercrime'', ''email'', and ''e-commerce''. In contrast, "offline" can refer to either computing activities performed while disconnected from the Internet, or alternatives to Internet activities (such as shopping in brick-and-mortar stores). The term "offline" is sometimes used interchang ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mandrel
A mandrel, mandril, or arbor is a tapered tool against which material can be forged, pressed, stretched or shaped (e.g., a ring mandrel - also called a triblet - used by jewellers to increase the diameter of a wedding ring), or a flanged or tapered or threaded bar that grips a workpiece to be machined in a lathe. A flanged mandrel is a parallel bar of a specific diameter with an integral flange towards one end, and threaded at the opposite end. Work is gripped between the flange and a nut on the thread. A tapered mandrel (often called a plain mandrel) has a taper of approximately 0.005 inches per foot and is designed to hold work by being driven into an accurate hole on the work, gripping the work by friction. A threaded mandrel may have a male or female thread, and work which has an opposing thread is screwed onto the mandrel. On a lathe, mandrels are commonly mounted between centres and driven by a lathe dog (typically flanged or tapered mandrels), but may also be gripped in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
U-matic
U-matic, also known as -inch Type E Helical Scan or SMPTE E, is an analog recording videocassette format developed by Sony. First shown as a prototype in October 1969 and introduced commercially in September 1971, it was among the earliest video formats to house videotape inside a cassette, replacing the reel-to-reel systems common at the time. The format uses tape, earning it the nickname "three-quarter-inch" or simply "three-quarter," in contrast to larger open-reel formats like Type C videotape and quadruplex videotape. The name ''U-matic'' refers to the U-shaped tape path as it threads around the video drum. Unlike most cassette formats, U-matic's supply and take-up reels rotate in opposite directions during playback, fast-forward, and rewind—one clockwise, the other counterclockwise. Each cassette has an internal locking mechanism that secures the tape hubs during transport, and a spring-loaded door that protects the tape; this door automatically opens when the casse ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Video
Video is an Electronics, electronic medium for the recording, copying, playback, broadcasting, and display of moving picture, moving image, visual Media (communication), media. Video was first developed for mechanical television systems, which were quickly replaced by cathode-ray tube (CRT) systems, which, in turn, were replaced by flat-panel displays of several types. Video systems vary in display resolution, Display aspect ratio, aspect ratio, refresh rate, color capabilities, and other qualities. Analog and digital variants exist and can be carried on a variety of media, including radio broadcasts, magnetic tape, optical discs, Video file format, computer files, and Streaming media, network streaming. Etymology The word ''video'' comes from the Latin verb ''video,'' meaning to see or ''videre''. And as a noun, "that which is displayed on a (television) screen," History Analog video Video developed from facsimile systems developed in the mid-19th century. Early mecha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Analog Signal
An analog signal (American English) or analogue signal (British and Commonwealth English) is any continuous-time signal representing some other quantity, i.e., ''analogous'' to another quantity. For example, in an analog audio signal, the instantaneous signal voltage varies continuously with the pressure of the sound waves. In contrast, a digital signal represents the original time-varying quantity as a sampled sequence of quantized values. Digital sampling imposes some bandwidth and dynamic range constraints on the representation and adds quantization noise. The term ''analog signal'' usually refers to electrical signals; however, mechanical, pneumatic, hydraulic, and other systems may also convey or be considered analog signals. Representation An analog signal uses some property of the medium to convey the signal's information. For example, an aneroid barometer uses rotary position as the signal to convey pressure information. In an electrical signal, the voltage, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Data8
The 8 mm backup format is a discontinued magnetic tape data storage format used in computer systems, pioneered by Exabyte Corporation. It is also known as Data8, often abbreviated to D8 and is written as D-Eight on some Sony branded media. Such systems can back up up to 60 GB of data depending on configuration. The cassettes have the same dimensions and construction as the cassettes used in 8 mm video format recorders and camcorders. Until the advent of Advanced Intelligent Tape, AIT, Exabyte was the sole vendor of 8 mm format tape drives. The company was formed with the aim of taking the 8 mm video format and making it suitable for data storage. They did so by building a reliable mechanism and data format that used the common 8 mm helical scan videotape technology that was available then. Exabyte's first 8 mm tape drive was made available in 1987. This was followed up with their Mammoth tape drive in 1996, and the Mammoth-2 (M2) in 1999. Exaby ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helical Scan
Helical scan is a method of recording high-frequency signals on magnetic tape, used in open-reel video tape recorders, video cassette recorders, digital audio tape recorders, and some computer tape drives. With this technique, magnetic tape heads (or head chips) are placed on a rotating head drum, which moves the chips at high speed by due to its high angular velocity. The speed of the head chips must be higher than the linear speed of the tape. The tape is wrapped tightly around the drum. The drum and/or the tape is tilted at an angle that allows the head chips to read the tape diagonally. The linear speed of the tape is slower than the speed of the head chips, allowing high frequency signals to be read or recorded, such as video. As the tape moves linearly or length-wise, the head chips move across the width of the tape in a diagonal path. Due to geometry, this allows for high head chip speeds, known as writing speeds, to be achieved in spite of the low linear speed of the tap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tape Head
''Tape Head'' is the seventh studio album by American rock band King's X, released in 1998 via Metal Blade Records. A music video was made for the song "Fade". "World" is a reworked song from the band's ''Sneak Preview'' demos. The controversial unreleased track "Quality Control" is included on the album, but has been re-titled to "Happy". The majority of the lyrics are now different, including the lack of profanity. The album cover picture is that of Doug Pinnick wrapped in recording tape. According to Pinnick, he brought the songs "Happy", "Cupid" and "Hate You", and Ty Tabor brought "Ocean" to the ''Tape Head'' recording sessions. All other songs were band created during the recording session. The song "Walter Bela Farkas" was recorded live August 8, 1996, at the Tramps nightclub in New York City. Track listing All songs written by King's X. Personnel * Doug Pinnick – bass, vocals * Ty Tabor – guitar, vocals * Jerry Gaskill – drums, vocals Additional ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helix
A helix (; ) is a shape like a cylindrical coil spring or the thread of a machine screw. It is a type of smooth space curve with tangent lines at a constant angle to a fixed axis. Helices are important in biology, as the DNA molecule is formed as two intertwined helices, and many proteins have helical substructures, known as alpha helices. The word ''helix'' comes from the Greek word , "twisted, curved". A "filled-in" helix – for example, a "spiral" (helical) ramp – is a surface called a '' helicoid''. Properties and types The pitch of a helix is the height of one complete helix turn, measured parallel to the axis of the helix. A double helix consists of two (typically congruent) helices with the same axis, differing by a translation along the axis. A circular helix (i.e. one with constant radius) has constant band curvature and constant torsion. The slope of a circular helix is commonly defined as the ratio of the circumference of the circular cylinder that it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetic Tape Data Storage
Magnetic-tape data storage is a system for storing digital information on magnetic tape using digital recording. Tape was an important medium for primary data storage in early computers, typically using large open reels of 7-track, later 9-track tape. Modern magnetic tape is most commonly packaged in cartridges and cassettes, such as the widely supported Linear Tape-Open (LTO) and IBM 3592 series. The device that performs the writing or reading of data is called a tape drive. Autoloaders and tape libraries are often used to automate cartridge handling and exchange. Compatibility was important to enable transferring data. Tape data storage is now used more for system backup, data archive and data exchange. The low cost of tape has kept it viable for long-term storage and archive. Open reels Initially, magnetic tape for data storage was wound on reels. This standard for large computer systems persisted through the late 1980s, with steadily increasing capacity d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tape Library
Tape or Tapes may refer to: Material Tape is long, narrow, thin strip of material usually used to stick things together. (see also Ribbon (other): Adhesive tapes * Adhesive tape, any of many varieties of backing materials coated with an adhesive * Athletic tape, pressure-sensitive tape that holds muscles or bones in certain positions * Box-sealing tape, a pressure-sensitive tape used for closing or sealing corrugated fiberboard boxes * Copper tape (or slug tape), adhesive-backed copper tape used to keep slugs and snails out of certain areas * Double-sided tape, any pressure-sensitive tape that is coated with adhesive on both sides * Duct tape, cloth- or scrim-backed pressure-sensitive tape often coated with polyethylene * Elastic therapeutic tape * Electrical tape, a type of pressure-sensitive tape used to insulate electrical wires and other materials that conduct electricity * Filament tape, a pressure-sensitive tape used for several packaging functions * Gaff ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
History Of IBM Magnetic Disk Drives
IBM manufactured magnetic disk storage devices from 1956 to 2003, when it sold its hard disk drive business to Hitachi. Both the hard disk drive (HDD) and floppy disk drive (FDD) were invented by IBM and as such IBM's employees were responsible for many of the innovations in these products and their technologies. The basic mechanical arrangement of hard disk drives has not changed since the IBM 1301. Disk drive performance and characteristics are measured by the same standards now as they were in the 1950s. Few products in history have enjoyed such spectacular declines in cost and physical size along with equally dramatic improvements in capacity and performance. IBM manufactured 8-inch floppy disk drives from 1969 until the mid-1980s, but did not become a significant manufacturer of smaller-sized, 5.25- or 3.5-inch floppy disk drives (the dimension refers to the diameter of the floppy disk, not the size of the drive). IBM always offered its magnetic disk drives for sale but did no ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
