A loom is a device used to weave cloth and tapestry . The basic purpose of any loom is to hold the warp threads under tension to facilitate the interweaving of the weft threads. The precise shape of the loom and its mechanics may vary, but the basic function is the same.
105-595: CALDIC (the California Digital Computer ) is an electronic digital computer built with the assistance of the Office of Naval Research at the University of California, Berkeley between 1951 and 1955 to assist and enhance research being conducted at the university with a platform for high-speed computing. CALDIC was designed to be constructed at a low cost and simple to operate, by standards of
210-521: A binary system meant that Zuse's machines were easier to build and potentially more reliable, given the technologies available at that time. The Z3 was not itself a universal computer but could be extended to be Turing complete . Zuse's next computer, the Z4 , became the world's first commercial computer; after initial delay due to the Second World War, it was completed in 1950 and delivered to
315-632: A central processing unit (CPU) in the form of a microprocessor , together with some type of computer memory , typically semiconductor memory chips. The processing element carries out arithmetic and logical operations, and a sequencing and control unit can change the order of operations in response to stored information . Peripheral devices include input devices ( keyboards , mice , joysticks , etc.), output devices ( monitors , printers , etc.), and input/output devices that perform both functions (e.g. touchscreens ). Peripheral devices allow information to be retrieved from an external source, and they enable
420-419: A keyboard , and computed and printed the results, demonstrating the feasibility of an electromechanical analytical engine. During the first half of the 20th century, many scientific computing needs were met by increasingly sophisticated analog computers, which used a direct mechanical or electrical model of the problem as a basis for computation . However, these were not programmable and generally lacked
525-466: A mass-production basis, which limited them to a number of specialized applications. At the University of Manchester , a team under the leadership of Tom Kilburn designed and built a machine using the newly developed transistors instead of valves. Their first transistorized computer and the first in the world, was operational by 1953 , and a second version was completed there in April 1955. However,
630-429: A monolithic integrated circuit (IC) chip. Kilby's IC had external wire connections, which made it difficult to mass-produce. Noyce also came up with his own idea of an integrated circuit half a year later than Kilby. Noyce's invention was the first true monolithic IC chip. His chip solved many practical problems that Kilby's had not. Produced at Fairchild Semiconductor, it was made of silicon , whereas Kilby's chip
735-652: A 1998 retrospective, it was the first working machine to contain all of the elements essential to a modern electronic computer. As soon as the Baby had demonstrated the feasibility of its design, a project began at the university to develop it into a practically useful computer, the Manchester Mark 1 . The Mark 1 in turn quickly became the prototype for the Ferranti Mark 1 , the world's first commercially available general-purpose computer. Built by Ferranti , it
840-512: A Chip (SoCs) are complete computers on a microchip (or chip) the size of a coin. They may or may not have integrated RAM and flash memory . If not integrated, the RAM is usually placed directly above (known as Package on package ) or below (on the opposite side of the circuit board ) the SoC, and the flash memory is usually placed right next to the SoC. This is done to improve data transfer speeds, as
945-503: A darning egg and a separate comb-like piece with teeth to hook the warp over; these are used for repairing knitted garments and are like a linear knitting spool . Darning looms were sold during World War Two clothing rationing in the United Kingdom and Canada, and some are homemade. Circular looms are used to create seamless tubes of fabric for products such as hosiery, sacks, clothing, fabric hoses (such as fire hoses) and
1050-477: A loom that folds into a narrow space when not in use. Loom frames can be roughly divided, by the orientation of the warp threads, into horizontal looms and vertical looms. There are many finer divisions. Most handloom frame designs can be constructed fairly simply. The back-strap loom (also known as belt loom) is a simple loom with ancient roots, still used in many cultures around the world (such as Andean textiles ). It consists of two sticks or bars between which
1155-441: A lot of floor space, and full-time professional weavers are unlikely to use them as they are unergonomic. Their cheapness and portability is less valuable to urban professional weavers. In a treadle loom, the shedding is controlled by the feet, which tread on the treadles . The earliest evidence of a horizontal loom is found on a pottery dish in ancient Egypt , dated to 4400 BC. It was a frame loom, equipped with treadles to lift
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#17327904374121260-403: A medieval European counting house , a checkered cloth would be placed on a table, and markers moved around on it according to certain rules, as an aid to calculating sums of money. The Antikythera mechanism is believed to be the earliest known mechanical analog computer , according to Derek J. de Solla Price . It was designed to calculate astronomical positions. It was discovered in 1901 in
1365-525: A much more general design, an analytical engine , was possible. The input of programs and data was to be provided to the machine via punched cards , a method being used at the time to direct mechanical looms such as the Jacquard loom . For output, the machine would have a printer, a curve plotter and a bell. The machine would also be able to punch numbers onto cards to be read in later. The engine would incorporate an arithmetic logic unit , control flow in
1470-529: A number of successes at breaking encrypted German military communications. The German encryption machine, Enigma , was first attacked with the help of the electro-mechanical bombes which were often run by women. To crack the more sophisticated German Lorenz SZ 40/42 machine, used for high-level Army communications, Max Newman and his colleagues commissioned Flowers to build the Colossus . He spent eleven months from early February 1943 designing and building
1575-402: A root of unknown origin; the whole word geloma meant a utensil, tool, or machine of any kind. In 1404 "lome" was used to mean a machine to enable weaving thread into cloth. By 1838 "loom" had gained the additional meaning of a machine for interlacing thread. Weaving is done on two sets of threads or yarns, which cross one another. The warp threads are the ones stretched on the loom (from
1680-562: A sequence of sets of values. The whole machine was to be controlled by a read-only program, which was complete with provisions for conditional branching . He also introduced the idea of floating-point arithmetic . In 1920, to celebrate the 100th anniversary of the invention of the arithmometer , Torres presented in Paris the Electromechanical Arithmometer, which allowed a user to input arithmetic problems through
1785-418: A shed. To create the counter-shed, a heddle-bar is usually used. A heddle-bar is simply a stick placed across the warp and tied to individual warp threads. When it is lifted, it pulls the warp threads it is tied to out of position, creating a shed. A warp-weighted loom (see diagram) typically uses a heddle-bar. It has two upright posts (C); they support a horizontal beam (D), which is cylindrical so that
1890-591: A single-shaft loom. The different shafts (also called harnesses) must be controlled by some mechanism. While non-rigid heddles generally mean that two shafts are needed even for a plain tabby weave , twill weaves require three or more (depending on the type of twill), and more complex figured weaves require still more harnesses. Treadle looms can control multiple harnessess with multiple treadles. The weaver selects which harnesses are engaged with their feet. One treadle may be connected to more than one harness, and any number of treadles can be engaged at once, meaning that
1995-460: A successful demonstration of its use in computing tables in 1906. In his work Essays on Automatics published in 1914, Leonardo Torres Quevedo wrote a brief history of Babbage's efforts at constructing a mechanical Difference Engine and Analytical Engine. The paper contains a design of a machine capable to calculate formulas like a x ( y − z ) 2 {\displaystyle a^{x}(y-z)^{2}} , for
2100-482: A tabletop. others are backstraps looms with a rigid heddle , and very portable. There exist very small hand-held looms known as darning looms. They are made to fit under the fabric being mended, and are often held in place by an elastic band on one side of the cloth and a groove around the loom's darning-egg portion on the other. They may have heddles made of flip-flopping rotating hooks (see Loom#Rotating-hook heddles ) . Other devices sold as darning looms are just
2205-402: A universal Turing machine. Early computing machines had fixed programs. Changing its function required the re-wiring and re-structuring of the machine. With the proposal of the stored-program computer this changed. A stored-program computer includes by design an instruction set and can store in memory a set of instructions (a program ) that details the computation . The theoretical basis for
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#17327904374122310-577: A wide range of tasks. The term computer system may refer to a nominally complete computer that includes the hardware , operating system , software , and peripheral equipment needed and used for full operation; or to a group of computers that are linked and function together, such as a computer network or computer cluster . A broad range of industrial and consumer products use computers as control systems , including simple special-purpose devices like microwave ovens and remote controls , and factory devices like industrial robots . Computers are at
2415-399: Is a device that replaces the drawboy, the weaver's helper who used to control the warp threads by pulling on draw threads. "Dobby" is a corruption of "draw boy". Mechanical dobbies pull on the draw threads using pegs in bars to lift a set of levers. The placement of the pegs determines which levers are lifted. The sequence of bars (they are strung together) effectively remembers the sequence for
2520-463: Is the stored program , where all the instructions for computing are stored in memory. Von Neumann acknowledged that the central concept of the modern computer was due to this paper. Turing machines are to this day a central object of study in theory of computation . Except for the limitations imposed by their finite memory stores, modern computers are said to be Turing-complete , which is to say, they have algorithm execution capability equivalent to
2625-409: Is used for narrow work . It is also used to finish edges, weaving decorative selvage bands instead of hemming. There are heddles made of flip-flopping rotating hooks, which raise and lower the warp, creating sheds . The hooks, when vertical, have the weft threads looped around them horizontally. If the hooks are flopped over on side or another, the loop of weft twists, raising one or the other side of
2730-563: Is used to control each warp thread separately, allowing very complex patterns. A drawloom requires two operators, the weaver, and an assistant called a "drawboy" to manage the figure harness. The earliest confirmed drawloom fabrics come from the State of Chu and date c. 400 BC. Some scholars speculate an independent invention in ancient Syria , since drawloom fabrics found in Dura-Europas are thought to date before 256 AD. The draw loom
2835-402: Is woven starting at one end of the warp threads, and progressing towards the other end. The beam on the finished-fabric end is called the cloth beam . The other beam is called the warp beam . Beams may be used as rollers to allow the weaver to weave a piece of cloth longer than the loom. As the cloth is woven, the warp threads are gradually unrolled from the warp beam, and the woven portion of
2940-619: The Antikythera wreck off the Greek island of Antikythera , between Kythera and Crete , and has been dated to approximately c. 100 BCE . Devices of comparable complexity to the Antikythera mechanism would not reappear until the fourteenth century. Many mechanical aids to calculation and measurement were constructed for astronomical and navigation use. The planisphere was a star chart invented by Abū Rayhān al-Bīrūnī in
3045-507: The E6B circular slide rule used for time and distance calculations on light aircraft. In the 1770s, Pierre Jaquet-Droz , a Swiss watchmaker , built a mechanical doll ( automaton ) that could write holding a quill pen. By switching the number and order of its internal wheels different letters, and hence different messages, could be produced. In effect, it could be mechanically "programmed" to read instructions. Along with two other complex machines,
3150-641: The ETH Zurich . The computer was manufactured by Zuse's own company, Zuse KG , which was founded in 1941 as the first company with the sole purpose of developing computers in Berlin. The Z4 served as the inspiration for the construction of the ERMETH , the first Swiss computer and one of the first in Europe. Purely electronic circuit elements soon replaced their mechanical and electromechanical equivalents, at
3255-506: The Proto-Indo-European * werp , "to bend" ). Each thread of the weft (i.e. "that which is woven") is inserted so that it passes over and under the warp threads. The ends of the warp threads are usually fastened to beams. One end is fastened to one beam, the other end to a second beam, so that the warp threads all lie parallel and are all the same length. The beams are held apart to keep the warp threads taut. The textile
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3360-497: The microcomputer revolution in the 1970s. The speed, power, and versatility of computers have been increasing dramatically ever since then, with transistor counts increasing at a rapid pace ( Moore's law noted that counts doubled every two years), leading to the Digital Revolution during the late 20th and early 21st centuries. Conventionally, a modern computer consists of at least one processing element , typically
3465-504: The "second generation" of computers. Compared to vacuum tubes, transistors have many advantages: they are smaller, and require less power than vacuum tubes, so give off less heat. Junction transistors were much more reliable than vacuum tubes and had longer, indefinite, service life. Transistorized computers could contain tens of thousands of binary logic circuits in a relatively compact space. However, early junction transistors were relatively bulky devices that were difficult to manufacture on
3570-525: The 1920s, Vannevar Bush and others developed mechanical differential analyzers. In the 1890s, the Spanish engineer Leonardo Torres Quevedo began to develop a series of advanced analog machines that could solve real and complex roots of polynomials , which were published in 1901 by the Paris Academy of Sciences . Charles Babbage , an English mechanical engineer and polymath , originated
3675-619: The Cambridge EDSAC of 1949, became operational in April 1951 and ran the world's first routine office computer job . The concept of a field-effect transistor was proposed by Julius Edgar Lilienfeld in 1925. John Bardeen and Walter Brattain , while working under William Shockley at Bell Labs , built the first working transistor , the point-contact transistor , in 1947, which was followed by Shockley's bipolar junction transistor in 1948. From 1955 onwards, transistors replaced vacuum tubes in computer designs, giving rise to
3780-591: The EDVAC in 1945. The Manchester Baby was the world's first stored-program computer . It was built at the University of Manchester in England by Frederic C. Williams , Tom Kilburn and Geoff Tootill , and ran its first program on 21 June 1948. It was designed as a testbed for the Williams tube , the first random-access digital storage device. Although the computer was described as "small and primitive" by
3885-455: The ENIAC were six women, often known collectively as the "ENIAC girls". It combined the high speed of electronics with the ability to be programmed for many complex problems. It could add or subtract 5000 times a second, a thousand times faster than any other machine. It also had modules to multiply, divide, and square root. High speed memory was limited to 20 words (about 80 bytes). Built under
3990-531: The MOS transistor, was invented at Bell Labs between 1955 and 1960 and was the first truly compact transistor that could be miniaturized and mass-produced for a wide range of uses. With its high scalability , and much lower power consumption and higher density than bipolar junction transistors, the MOSFET made it possible to build high-density integrated circuits . In addition to data processing, it also enabled
4095-455: The Scottish scientist Sir William Thomson in 1872 was of great utility to navigation in shallow waters. It used a system of pulleys and wires to automatically calculate predicted tide levels for a set period at a particular location. The differential analyser , a mechanical analog computer designed to solve differential equations by integration , used wheel-and-disc mechanisms to perform
4200-493: The U.S. Although the ENIAC was similar to the Colossus, it was much faster, more flexible, and it was Turing-complete. Like the Colossus, a "program" on the ENIAC was defined by the states of its patch cables and switches, a far cry from the stored program electronic machines that came later. Once a program was written, it had to be mechanically set into the machine with manual resetting of plugs and switches. The programmers of
4305-586: The US, John Vincent Atanasoff and Clifford E. Berry of Iowa State University developed and tested the Atanasoff–Berry Computer (ABC) in 1942, the first "automatic electronic digital computer". This design was also all-electronic and used about 300 vacuum tubes, with capacitors fixed in a mechanically rotating drum for memory. During World War II, the British code-breakers at Bletchley Park achieved
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4410-898: The advent of the integrated circuit (IC). The idea of the integrated circuit was first conceived by a radar scientist working for the Royal Radar Establishment of the Ministry of Defence , Geoffrey W.A. Dummer . Dummer presented the first public description of an integrated circuit at the Symposium on Progress in Quality Electronic Components in Washington, D.C. , on 7 May 1952. The first working ICs were invented by Jack Kilby at Texas Instruments and Robert Noyce at Fairchild Semiconductor . Kilby recorded his initial ideas concerning
4515-505: The backstrap loom. The warp-weighted loom is a vertical loom that may have originated in the Neolithic period. Its defining characteristic is hanging weights (loom weights) which keep bundles of the warp threads taut. Frequently, extra warp thread is wound around the weights. When a weaver has woven far enough down, the completed section (fell) can be rolled around the top beam, and additional lengths of warp threads can be unwound from
4620-647: The basic concept which underlies all electronic digital computers. By 1938, the United States Navy had developed an electromechanical analog computer small enough to use aboard a submarine . This was the Torpedo Data Computer , which used trigonometry to solve the problem of firing a torpedo at a moving target. During World War II similar devices were developed in other countries as well. Early digital computers were electromechanical ; electric switches drove mechanical relays to perform
4725-477: The beams can be simply held apart by hooking them behind pegs driven into the ground, with wedges or lashings used to adjust the tension. Pegged looms may, however, also have horizontal sidepieces holding the beams apart. Such looms are easy to set up and dismantle, and are easy to transport, so they are popular with nomadic weavers. They are generally only used for comparatively small woven articles. Urbanites are unlikely to use horizontal floor looms as they take up
4830-530: The best Arithmetician that euer [ sic ] breathed, and he reduceth thy dayes into a short number." This usage of the term referred to a human computer , a person who carried out calculations or computations . The word continued to have the same meaning until the middle of the 20th century. During the latter part of this period, women were often hired as computers because they could be paid less than their male counterparts. By 1943, most human computers were women. The Online Etymology Dictionary gives
4935-570: The calculation. These devices had a low operating speed and were eventually superseded by much faster all-electric computers, originally using vacuum tubes . The Z2 , created by German engineer Konrad Zuse in 1939 in Berlin , was one of the earliest examples of an electromechanical relay computer. In 1941, Zuse followed his earlier machine up with the Z3 , the world's first working electromechanical programmable , fully automatic digital computer. The Z3
5040-538: The cloth is rolled up onto the cloth beam (which is also called the takeup roll ). The portion of the fabric that has already been formed but not yet rolled up on the takeup roll is called the fell . Not all looms have two beams. For instance, warp-weighted looms have only one beam; the warp yarns hang from this beam. The bottom ends of the warp yarns are tied to dangling loom weights. A loom has to perform three principal motions : shedding, picking, and battening. There are also usually two secondary motions , because
5145-503: The computer disk industry). The machine was first ready for use in the summer of 1953 and mostly operational in 1954. Development cost through July 1955 was approximately $ 150,000. Digital computer A computer is a machine that can be programmed to automatically carry out sequences of arithmetic or logical operations ( computation ). Modern digital electronic computers can perform generic sets of operations known as programs . These programs enable computers to perform
5250-565: The concept of a programmable computer. Considered the " father of the computer ", he conceptualized and invented the first mechanical computer in the early 19th century. After working on his difference engine he announced his invention in 1822, in a paper to the Royal Astronomical Society , titled "Note on the application of machinery to the computation of astronomical and mathematical tables". He also designed to aid in navigational calculations, in 1833 he realized that
5355-704: The core of general-purpose devices such as personal computers and mobile devices such as smartphones . Computers power the Internet , which links billions of computers and users. Early computers were meant to be used only for calculations. Simple manual instruments like the abacus have aided people in doing calculations since ancient times. Early in the Industrial Revolution , some mechanical devices were built to automate long, tedious tasks, such as guiding patterns for looms . More sophisticated electrical machines did specialized analog calculations in
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#17327904374125460-499: The data signals do not have to travel long distances. Since ENIAC in 1945, computers have advanced enormously, with modern SoCs (such as the Snapdragon 865) being the size of a coin while also being hundreds of thousands of times more powerful than ENIAC, integrating billions of transistors, and consuming only a few watts of power. The first mobile computers were heavy and ran from mains power. The 50 lb (23 kg) IBM 5100
5565-515: The decision of the British Government to cease funding. Babbage's failure to complete the analytical engine can be chiefly attributed to political and financial difficulties as well as his desire to develop an increasingly sophisticated computer and to move ahead faster than anyone else could follow. Nevertheless, his son, Henry Babbage , completed a simplified version of the analytical engine's computing unit (the mill ) in 1888. He gave
5670-499: The design. Multiple rows of holes are punched on each card and the many cards that compose the design of the textile are strung together in order. It is based on earlier inventions by the Frenchmen Basile Bouchon (1725), Jean Baptiste Falcon (1728), and Jacques Vaucanson (1740). To call it a loom is a misnomer. A Jacquard head could be attached to a power loom or a handloom, the head controlling which warp thread
5775-460: The direction of John Mauchly and J. Presper Eckert at the University of Pennsylvania, ENIAC's development and construction lasted from 1943 to full operation at the end of 1945. The machine was huge, weighing 30 tons, using 200 kilowatts of electric power and contained over 18,000 vacuum tubes, 1,500 relays, and hundreds of thousands of resistors, capacitors, and inductors. The principle of
5880-483: The doll is at the Musée d'Art et d'Histoire of Neuchâtel , Switzerland , and still operates. In 1831–1835, mathematician and engineer Giovanni Plana devised a Perpetual Calendar machine , which through a system of pulleys and cylinders could predict the perpetual calendar for every year from 0 CE (that is, 1 BCE) to 4000 CE, keeping track of leap years and varying day length. The tide-predicting machine invented by
5985-481: The early 11th century. The astrolabe was invented in the Hellenistic world in either the 1st or 2nd centuries BCE and is often attributed to Hipparchus . A combination of the planisphere and dioptra , the astrolabe was effectively an analog computer capable of working out several different kinds of problems in spherical astronomy . An astrolabe incorporating a mechanical calendar computer and gear -wheels
6090-523: The early 2000s. These smartphones and tablets run on a variety of operating systems and recently became the dominant computing device on the market. These are powered by System on a Chip (SoCs), which are complete computers on a microchip the size of a coin. Computers can be classified in a number of different ways, including: Loom The word "loom" derives from the Old English geloma , formed from ge- (perfective prefix) and loma ,
6195-399: The early 20th century. The first digital electronic calculating machines were developed during World War II , both electromechanical and using thermionic valves . The first semiconductor transistors in the late 1940s were followed by the silicon -based MOSFET (MOS transistor) and monolithic integrated circuit chip technologies in the late 1950s, leading to the microprocessor and
6300-477: The exact definition of the term "microprocessor", it is largely undisputed that the first single-chip microprocessor was the Intel 4004 , designed and realized by Federico Faggin with his silicon-gate MOS IC technology, along with Ted Hoff , Masatoshi Shima and Stanley Mazor at Intel . In the early 1970s, MOS IC technology enabled the integration of more than 10,000 transistors on a single chip. System on
6405-415: The fell. The nature of the loom frame and the shedding, picking, and battening devices vary. Looms come in a wide variety of types, many of them specialized for specific types of weaving. They are also specialized for the lifestyle of the weaver. For instance, nomadic weavers tend to use lighter, more portable looms, while weavers living in cramped city dwellings are more likely to use a tall upright loom, or
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#17327904374126510-422: The finished cloth can be rolled around it, allowing the loom to be used to weave a piece of cloth taller than the loom, and preserving an ergonomic working height. The warp threads (F, and A and B) hang from the beam and rest against the shed rod (E). The heddle-bar (G) is tied to some of the warp threads (A, but not B), using loops of string called leashes (H). So when the heddle rod is pulled out and placed in
6615-508: The first Colossus. After a functional test in December 1943, Colossus was shipped to Bletchley Park, where it was delivered on 18 January 1944 and attacked its first message on 5 February. Colossus was the world's first electronic digital programmable computer. It used a large number of valves (vacuum tubes). It had paper-tape input and was capable of being configured to perform a variety of boolean logical operations on its data, but it
6720-725: The first attested use of computer in the 1640s, meaning 'one who calculates'; this is an "agent noun from compute (v.)". The Online Etymology Dictionary states that the use of the term to mean " 'calculating machine' (of any type) is from 1897." The Online Etymology Dictionary indicates that the "modern use" of the term, to mean 'programmable digital electronic computer' dates from "1945 under this name; [in a] theoretical [sense] from 1937, as Turing machine ". The name has remained, although modern computers are capable of many higher-level functions. Devices have been used to aid computation for thousands of years, mostly using one-to-one correspondence with fingers . The earliest counting device
6825-466: The forked sticks protruding from the posts (not lettered, no technical term given in citation), the shed (1) is replaced by the counter-shed (2). By passing the weft through the shed and the counter-shed, alternately, cloth is woven. Heddle-rods are used on modern tapestry looms. Tablet weaving uses cards punched with holes. The warp threads pass through the holes, and the cards are twisted and shifted to created varied sheds. This shedding technique
6930-409: The form of conditional branching and loops , and integrated memory , making it the first design for a general-purpose computer that could be described in modern terms as Turing-complete . The machine was about a century ahead of its time. All the parts for his machine had to be made by hand – this was a major problem for a device with thousands of parts. Eventually, the project was dissolved with
7035-466: The integrated circuit in July 1958, successfully demonstrating the first working integrated example on 12 September 1958. In his patent application of 6 February 1959, Kilby described his new device as "a body of semiconductor material ... wherein all the components of the electronic circuit are completely integrated". However, Kilby's invention was a hybrid integrated circuit (hybrid IC), rather than
7140-411: The integration. In 1876, Sir William Thomson had already discussed the possible construction of such calculators, but he had been stymied by the limited output torque of the ball-and-disk integrators . In a differential analyzer, the output of one integrator drove the input of the next integrator, or a graphing output. The torque amplifier was the advance that allowed these machines to work. Starting in
7245-538: The latter two had been involved with the ENIAC at the University of Pennsylvania , and Lehmer had given one of the Moore School Lectures . Morton oversaw the design and construction with a team comprising electrical engineering graduate and undergraduate students at the university, more than 35 in total, including Doug Engelbart (who later invented the computer mouse ) and Al Hoagland (a pioneer of
7350-497: The like. Tablet weaving can be used to knit tubes, including tubes that split and join. Small jigs also used for circular knitting are also sometimes called circular looms, but they are used for knitting, not weaving. It is possible to weave by manually threading the weft over and under the warp threads, but this is slow. Some tapestry techniques use manual shedding. Pin looms and peg looms also generally have no shedding devices. Pile carpets generally do not use shedding for
7455-436: The loop, which creates the shed and countershed. Rigid heddles are generally used on single-shaft looms. Odd warp threads go through the slots, and even ones through the circular holes, or vice-versa. The shed is formed by lifting the heddle, and the countershed by depressing it. The warp threads in the slots stay where they are, and the ones in the circular holes are pulled back and forth. A single rigid heddle can hold all
7560-590: The machine did make use of valves to generate its 125 kHz clock waveforms and in the circuitry to read and write on its magnetic drum memory , so it was not the first completely transistorized computer. That distinction goes to the Harwell CADET of 1955, built by the electronics division of the Atomic Energy Research Establishment at Harwell . The metal–oxide–silicon field-effect transistor (MOSFET), also known as
7665-452: The modern computer was proposed by Alan Turing in his seminal 1936 paper, On Computable Numbers . Turing proposed a simple device that he called "Universal Computing machine" and that is now known as a universal Turing machine . He proved that such a machine is capable of computing anything that is computable by executing instructions (program) stored on tape, allowing the machine to be programmable. The fundamental concept of Turing's design
7770-403: The more famous Sir William Thomson. The art of mechanical analog computing reached its zenith with the differential analyzer , built by H. L. Hazen and Vannevar Bush at MIT starting in 1927. This built on the mechanical integrators of James Thomson and the torque amplifiers invented by H. W. Nieman. A dozen of these devices were built before their obsolescence became obvious. By the 1950s,
7875-636: The newly constructed fabric must be wound onto cloth beam. This process is called taking up. At the same time, the warp yarns must be let off or released from the warp beam, unwinding from it. To become fully automatic, a loom needs a tertiary motion , the filling stop motion. This will brake the loom if the weft thread breaks. An automatic loom requires 0.125 hp to 0.5 hp to operate (100W to 400W). A loom, then, usually needs two beams, and some way to hold them apart. It generally has additional components to make shedding, picking, and battening faster and easier. There are also often components to help take up
7980-417: The number of different sheds that can be selected is two to the power of the number of treadles. Eight is a large but reasonable number of treadles, giving a maximum of 2 =256 sheds (some of which will not have enough threads on one side to be useful). The weaver must remember the sequence of treadling needed to produce the pattern. A drawloom is for weaving figured cloth. In a drawloom, a "figure harness"
8085-586: The pattern. Speed is lower, and shedding and picking devices may be simpler. Looms used for weaving traditional tapestry are called not as "vertical-warp" and "horizontal-warp", but as "high-warp" or "low-warp" (the French terms haute-lisse and basse-lisse are also used in English). Inkle looms are narrow looms used for narrow work . They are used to make narrow warp-faced strips such as ribbons, bands, or tape. They are often quite small; some are used on
8190-409: The pile, because each pile thread is individually knotted onto the warps, but there may be shedding for the weft holding the carpet together. Usually weaving uses shedding devices. These devices pull some of the warp threads to each side, so that a shed is formed between them, and the weft is passed through the shed. There are a variety of methods for forming the shed. At least two sheds must be formed,
8295-486: The practical use of MOS transistors as memory cell storage elements, leading to the development of MOS semiconductor memory , which replaced earlier magnetic-core memory in computers. The MOSFET led to the microcomputer revolution , and became the driving force behind the computer revolution . The MOSFET is the most widely used transistor in computers, and is the fundamental building block of digital electronics . The next great advance in computing power came with
8400-400: The recording heads), and 12 relays (in the power supply). It weighed about 1,500 pounds (680 kg). It was capable of speeds of 50 iterations per second. CALDIC was a stored program computer with a six-digit instruction format (two digits for the opcode and four digits for the memory address). The computer was initially planned by Paul Morton , Leland Cunningham , and Dick Lehmer ;
8505-548: The results of operations to be saved and retrieved. It was not until the mid-20th century that the word acquired its modern definition; according to the Oxford English Dictionary , the first known use of the word computer was in a different sense, in a 1613 book called The Yong Mans Gleanings by the English writer Richard Brathwait : "I haue [ sic ] read the truest computer of Times, and
8610-591: The same time that digital calculation replaced analog. The engineer Tommy Flowers , working at the Post Office Research Station in London in the 1930s, began to explore the possible use of electronics for the telephone exchange . Experimental equipment that he built in 1934 went into operation five years later, converting a portion of the telephone exchange network into an electronic data processing system, using thousands of vacuum tubes . In
8715-408: The shed and the countershed. Two sheds is enough for tabby weave ; more complex weaves, such as twill weaves , satin weaves , diaper weaves , and figured (picture-forming) weaves, require more sheds. A shed-rod (shedding stick, shed roll) is simply a stick woven through the warp threads. When pulled perpendicular to the threads (or rotated to stand on edge, for wide, flat shedding rods), it creates
8820-490: The stored-program computer was laid out by Alan Turing in his 1936 paper. In 1945, Turing joined the National Physical Laboratory and began work on developing an electronic stored-program digital computer. His 1945 report "Proposed Electronic Calculator" was the first specification for such a device. John von Neumann at the University of Pennsylvania also circulated his First Draft of a Report on
8925-443: The success of digital electronic computers had spelled the end for most analog computing machines, but analog computers remained in use during the 1950s in some specialized applications such as education ( slide rule ) and aircraft ( control systems ). Claude Shannon 's 1937 master's thesis laid the foundations of digital computing, with his insight of applying Boolean algebra to the analysis and synthesis of switching circuits being
9030-477: The threads (those passing through the heddles), and lowering the shaft lowers the same threads — the threads passing through the spaces between the heddles remain in place. A treadle loom for figured weaving may have a large number of harnesses or a control head. It can, for instance, have a Jacquard machine attached to it (see Loom#Shedding methods) . Tapestry can have extremely complex wefts, as different strands of wefts of different colours are used to form
9135-478: The time, note that in a pre-1965 context there is no interactive user IO or human readable output in printed characters in most computers. There is no human readable user interface. It was a serial decimal machine with an 8-inch-diameter (200 mm), 10,000-word magnetic drum memory. (As CALDIC's decimal words were 10 digits each, the magnetic memory could store about 400,000 bits.) It contained 1,300 vacuum tubes , 1,000 crystal diodes , 100 magnetic elements (for
9240-412: The versatility and accuracy of modern digital computers. The first modern analog computer was a tide-predicting machine , invented by Sir William Thomson (later to become Lord Kelvin) in 1872. The differential analyser , a mechanical analog computer designed to solve differential equations by integration using wheel-and-disc mechanisms, was conceptualized in 1876 by James Thomson , the elder brother of
9345-416: The warp threads, leaving the weaver's hands free to pass and beat the weft thread. A pit loom has a pit for the treadles, reducing the stress transmitted through the much shorter frame. In a wooden vertical-shaft loom, the heddles are fixed in place in the shaft. The warp threads pass alternately through a heddle, and through a space between the heddles (the shed ), so that raising the shaft raises half
9450-450: The warp threads, though sometimes multiple rigid heddles are used. Treadles may be used to drive the rigid heddle up and down. Rigid heddles (above) are called "rigid" to distinguish them from string and metal heddles, where each warp thread has its own heddle, which has an eye at each end and one in the middle for the warp thread. The eyes in the ends are fastened to a shaft, all in a row. This requires multiple shafts; it cannot be done on
9555-563: The warps are stretched. One bar is attached to a fixed object and the other to the weaver, usually by means of a strap around the weaver's back. The weaver leans back and uses their body weight to tension the loom. Both simple and complex textiles can be woven on backstrap looms. They produce narrowcloth : width is limited to the weaver's armspan. They can readily produce warp-faced textiles, often decorated with intricate pick-up patterns woven in complementary and supplementary warp techniques, and brocading. Balanced weaves are also possible on
9660-400: The weaver. Computer-controlled dobbies use solenoids instead of pegs. The Jacquard loom is a mechanical loom, invented by Joseph Marie Jacquard in 1801, which simplifies the process of manufacturing figured textiles with complex patterns such as brocade , damask , and matelasse . The loom is controlled by punched cards with punched holes, each row of which corresponds to one row of
9765-408: The weights to continue. This frees the weaver from vertical size constraint. Horizontally, breadth is limited by armspan; making broadwoven cloth requires two weavers, standing side by side at the loom. Simple weaves, and complex weaves that need more than two different sheds, can both be woven on a warp-weighted loom. They can also be used to produce tapestries. [REDACTED] In pegged looms,
9870-406: Was a 16-transistor chip built by Fred Heiman and Steven Hofstein at RCA in 1962. General Microelectronics later introduced the first commercial MOS IC in 1964, developed by Robert Norman. Following the development of the self-aligned gate (silicon-gate) MOS transistor by Robert Kerwin, Donald Klein and John Sarace at Bell Labs in 1967, the first silicon-gate MOS IC with self-aligned gates
9975-625: Was an early example. Later portables such as the Osborne 1 and Compaq Portable were considerably lighter but still needed to be plugged in. The first laptops, such as the Grid Compass , removed this requirement by incorporating batteries – and with the continued miniaturization of computing resources and advancements in portable battery life, portable computers grew in popularity in the 2000s. The same developments allowed manufacturers to integrate computing resources into cellular mobile phones by
10080-537: Was built with 2000 relays , implementing a 22 bit word length that operated at a clock frequency of about 5–10 Hz . Program code was supplied on punched film while data could be stored in 64 words of memory or supplied from the keyboard. It was quite similar to modern machines in some respects, pioneering numerous advances such as floating-point numbers . Rather than the harder-to-implement decimal system (used in Charles Babbage 's earlier design), using
10185-511: Was delivered to the University of Manchester in February 1951. At least seven of these later machines were delivered between 1953 and 1957, one of them to Shell labs in Amsterdam . In October 1947 the directors of British catering company J. Lyons & Company decided to take an active role in promoting the commercial development of computers. Lyons's LEO I computer, modelled closely on
10290-443: Was developed by Federico Faggin at Fairchild Semiconductor in 1968. The MOSFET has since become the most critical device component in modern ICs. The development of the MOS integrated circuit led to the invention of the microprocessor , and heralded an explosion in the commercial and personal use of computers. While the subject of exactly which device was the first microprocessor is contentious, partly due to lack of agreement on
10395-825: Was developed in the late 16th century and found application in gunnery, surveying and navigation. The planimeter was a manual instrument to calculate the area of a closed figure by tracing over it with a mechanical linkage. The slide rule was invented around 1620–1630, by the English clergyman William Oughtred , shortly after the publication of the concept of the logarithm . It is a hand-operated analog computer for doing multiplication and division. As slide rule development progressed, added scales provided reciprocals, squares and square roots, cubes and cube roots, as well as transcendental functions such as logarithms and exponentials, circular and hyperbolic trigonometry and other functions . Slide rules with special scales are still used for quick performance of routine calculations, such as
10500-449: Was invented by Abi Bakr of Isfahan , Persia in 1235. Abū Rayhān al-Bīrūnī invented the first mechanical geared lunisolar calendar astrolabe, an early fixed- wired knowledge processing machine with a gear train and gear-wheels, c. 1000 AD . The sector , a calculating instrument used for solving problems in proportion, trigonometry , multiplication and division, and for various functions, such as squares and cube roots,
10605-562: Was invented in China during the Han dynasty ( State of Liu ?); foot-powered multi-harness looms and jacquard looms were used for silk weaving and embroidery, both of which were cottage industries with imperial workshops. The drawloom enhanced and sped up the production of silk and played a significant role in Chinese silk weaving. The loom was introduced to Persia, India, and Europe. A dobby head
10710-477: Was made of germanium . Noyce's monolithic IC was fabricated using the planar process , developed by his colleague Jean Hoerni in early 1959. In turn, the planar process was based on Carl Frosch and Lincoln Derick work on semiconductor surface passivation by silicon dioxide. Modern monolithic ICs are predominantly MOS ( metal–oxide–semiconductor ) integrated circuits, built from MOSFETs (MOS transistors). The earliest experimental MOS IC to be fabricated
10815-643: Was most likely a form of tally stick . Later record keeping aids throughout the Fertile Crescent included calculi (clay spheres, cones, etc.) which represented counts of items, likely livestock or grains, sealed in hollow unbaked clay containers. The use of counting rods is one example. The abacus was initially used for arithmetic tasks. The Roman abacus was developed from devices used in Babylonia as early as 2400 BCE. Since then, many other forms of reckoning boards or tables have been invented. In
10920-434: Was not Turing-complete. Nine Mk II Colossi were built (The Mk I was converted to a Mk II making ten machines in total). Colossus Mark I contained 1,500 thermionic valves (tubes), but Mark II with 2,400 valves, was both five times faster and simpler to operate than Mark I, greatly speeding the decoding process. The ENIAC (Electronic Numerical Integrator and Computer) was the first electronic programmable computer built in
11025-402: Was raised during shedding. Multiple shuttles could be used to control the colour of the weft during picking. The Jacquard loom is the predecessor to the computer punched card readers of the 19th and 20th centuries. The weft may be passed across the shed as a ball of yarn, but usually this is too bulky and unergonomic. Shuttles are designed to be slim, so they pass through the shed; to carry
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