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Jacquard, Joseph Marie

cards weaving punched pattern

(1752–1834) French technologist: devised an improved loom incorporating control by punched cards, a basic element of automation.

Jacquard served apprenticeships in bookbinding, cutlery making and typefounding and then, inheriting from his parents a small weaving business, he attempted to make his living as a weaver. However, weaving patterns attractive enough to sell well was slow and difficult: his business failed and he returned to cutlery. His interest in pattern weaving remained, and during the 1790s he devised improvements in looms, as well as taking an active part on the revolutionary side in the defence of his home town, Lyon.

By 1801 he was weaving fishing nets on a loom which combined several improvements, mainly devised by others. Demonstrated in Paris in 1804, it impressed Napoleon and led to a medal, a patent and a pension. Encouraged, he went on to make his major improvement, which was to be of value outside textiles. This was his use of cards with punched holes to control cams that directed pattern weaving. Improved further by others, chains of cards proved reliable enough before 1820 to cause violence by underemployed traditional weavers, and by the 1830s many were in use. Jacquard’s method of coding information for manual looms implies that a hole or its absence can correspond to an ‘on or off’ action-or to 0 and 1 in binary notation. Punched cards were planned by in the 1830s to programme his mechanical calculators, and in 1890 used 288-hole cards to process the US census returns. The pianola was another example.

Although Jacquard’s method became dominant in textile pattern making, the principle of using punched cards or tape had to await the replacement of mechanical sensing by electronic computers and magnetic tape or discs before, in this much altered form, it could take a large part in the powered machine tool industry.

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about 6 years ago

Le simulating light ray bunch bleeding by typically selection 0,1 logics can be formulated using LED sensors,magnetic field sensors uor piezoelectric sensors in nano cards of purely magnetic or electric quantum dots by maglev projections may form the basic punch cards.
Differentiable punch cards to storage informations in controlling Servomechanisms
The command signal may be derived from a punch card, a tape a tachometer, a potentiometer or other device and converted as pulse width voltage based or frequency base modulated pulses for further amplification .
The original RAMAC had a single pair of heads, each consisting of wire wrapped around a magnetic core. By running a pattern of electrical pulses through the wire, the head created a corresponding pattern of magnetic fields that magnetized bits on a circular track directly below on the spinning disk. To read back the data, the head was placed above the track. As the bits spun beneath the head, the sweep of their magnetic fields generated opposing voltages in the head. Today's disk drives use the same general design.
Magnetic field may produce piezo electric effect out of levitation in punching cards :
The first demonstration of the direct piezoelectric effect was in 1880 by the brothers Pierre Curie and Jacques Curie. They combined their knowledge of pyroelectricity with their understanding of the underlying crystal structures that gave rise to pyroelectricity to predict crystal behavior, and demonstrated the effect using crystals of tourmaline, quartz, topaz, cane sugar, and Rochelle salt (sodium potassium tartrate tetrahydrate). Quartz and Rochelle salt exhibited the most piezoelectricity.
During World War II, independent research groups in the United States, Russia, and Japan discovered a new class of man-made materials, called ferroelectrics, which exhibited piezoelectric constants many times higher than natural materials. This led to intense research to develop barium titanate and later lead zirconate titanate materials with specific properties for particular applications.
A piezoelectric transformer is a type of AC voltage multiplier. Unlike a conventional transformer, which uses magnetic coupling between input and output, the piezoelectric transformer uses acoustic coupling. An input voltage is applied across a short length of a bar of piezoceramic material such as PZT, creating an alternating stress in the bar by the inverse piezoelectric effect and causing the whole bar to vibrate. The vibration frequency is chosen to be the resonant frequency of the block, typically in the 100 kilohertz to 1 megahertz range. A higher output voltage is then generated across another section of the bar by the piezoelectric effect. Step-up ratios of more than 1000:1 have been demonstrated. An extra feature of this transformer is that, by operating it above its resonant frequency, it can be made to appear as an inductive load, which is useful in circuits that require a controlled soft start.[21] These devices can be used in DC-AC inverters to drive cold cathode fluorescent lamps. Piezo transformers are some of the most compact high voltage sources.
Diamagnetism is the property of an object which causes it to create a magnetic field in opposition to an externally applied magnetic field, thus causing a repulsive effect. Specifically, an external magnetic field alters the orbital velocity of electrons around their nuclei, thus changing the magnetic dipole moment. According to Lenz's law, this opposes the external field. Diamagnets are materials with a magnetic permeability less than μ0 (a relative permeability less than 1). Consequently, diamagnetism is a form of magnetism that is only exhibited by a substance in the presence of an externally applied magnetic field. It is generally quite a weak effect in most materials, although superconductors exhibit a strong effect. Diamagnetic materials cause lines of magnetic flux to curve away from the material, and superconductors can exclude them completely (except for a very thin layer at the surface).

A substance that is diamagnetic repels a magnetic field. All materials have diamagnetic properties, but the effect is very weak, and is usually overcome by the object's paramagnetic or ferromagnetic properties, which act in the opposite manner. Any material in which the diamagnetic component is strongest will be repelled by a magnet, though this force is usually weak. Diamagnetic levitation can be used to levitate very light pieces of pyrolytic graphite or bismuth above a moderately strong permanent magnet. As water is predominantly diamagnetic, this technique has been used to levitate water droplets.

Ferromagnetic sensors: We can imagine this imbalance being created by the injection of spin polarized charge carriers from a ferromagnet, which acts as a spin polarizer. Alternatively, we could build devices from ferromagnetic semiconductors that have an intrinsic spin imbalance. For
instance, a semiconductor spintronic device generically requires an imbalance between spin “up” and “down” populations of electrons (or holes). Ferromagnetic elements for injecting, detecting, and manipulating spins that can be use in embedded electronics. But, discoveries in recent years have inspired a completely different avenue to semiconductor spintronics—one that does not involve any ferromagnetism. track—“spintronics without magnetism”—relies on our ability to manipulate carrier spins in semiconductors through the spinorbit interaction.
This is easy to understand in a qualitative way by recalling that spin-orbit coupling is the natural outcome of incorporating special relativity within quantum mechanics (the Dirac and Pauli equations). In the rest frame of an electron moving through a lattice, the external electric field (along with that from the atomic cores) is Lorentz transformed into a magnetic field that can act upon the spin of the electron.
The spin-orbit coupling generates spin polarization through two conceptually different processes.
Spin dependent scattering and the acquisition of a geometric phase. The former idea harks back to the heyday of quantum mechanics, when Sir Neville Mott first used the Dirac equation to calculate the spin-dependent skew scattering of relativistic electrons by a Coulomb potential, in which electrons with spin up and down are scattered in opposite trajectories. Mott’s argument has
now resurfaced within condensed matter physics in the anomalous and spin Hall effects. Further, band-structure effects provide variations on this interplay between scattering and the spin-orbit interaction by the removal of spin degeneracy in momentum space This removal of spin degeneracy acts like an “effective magnetic field” that can be engineered into a semiconductor
crystal by using factors such as strain.
Several recent proposals have now shown how transported spins can acquire a geometric—or “topological”—phase in the presence of unusual band structures .Once a spin-polarized current is generated in a semiconductor, we can use the spin-orbit interaction to further modulate this spin polarization by taking advantage of symmetry-breaking factors such as interfaces, electric fields, strain, and crystalline directions.
Spin Hall’s Effect:The spin Hall effect arises when a current flows through a semiconductor in the presence of a spin-orbit interaction, creating spin accumulation at the edges of a semiconductor transport channel