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Herman Hollerith - Реферат


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Herman Hollerith
(1860-1929)
Herman Hollerith (February 29, 1860 - November 17, 1929) was an American statistician who developed a mechanical system based on punched cards to rapidly tabulate statistics from thousands and millions of data.
Personal Life
He was born on February 29, 1860 in Buffalo, New York to Johann George Hollerith (1808-1869); and Franciska Brunn, both of Rheinfalz, Germany. He graduated from City College of New York, with a bachelor's degree in 1879. In 1880 he listed himself as a mining engineer while living in Manhattan, and he completed his Ph.D. in 1890 at the Columbia College of Mines. In 1890 he married Lucia Beverley Talcott (1865-?) of Vera Cruz, Mexico and they had six children. He died in 1929 of a heart attack and was buried in the Oak Hill Cemetery in Georgetown, Virginia.
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Electronic tabulation of statistical data
Hollerith spent 1882 on the Mechanical Engineering faculty at MIT. During that year he developed a prototype of a system for storing data on punched cards which was partly inspired by the system used by railroad conductors in which holes punched in various places on a passenger's ticket identified the holder's passenger status. Urged on by John Shaw Billings, he developed a mechanism for reading the presence or absence of holes in the cards using spring-mounted needles that passed through the holes to make electrical connections to trigger a counter to record one more of each value. The key idea (due to Billings) was that all personal data could be coded numerically. Hollerith saw that the numbers could be punched in specified column on the cards, the cards sorted mechanically, and the appropriate columns totalled. He described his idea in Patent No. 395,782 of January 8, 1889 as follows:
The herein described method of compiling statistics which consists in recording separate statistical items pertaining to the individual by holes or combinations of holed punched in sheets of electrically non-conducting material, and bearing a specific relation to each other and to a standard, and then counting or tallying such statistical items separately or in combination by means of mechanical counters operated by electro-magnets the circuits through which are controlled by the perforated sheets, substantially as and for the purpose set forth.
Tabulating Machine Company
He built machines under contract for the US Census Bureau, which used them to tabulate the 1890 census in much less time than the 1880 census. He started his own business in 1896 when he founded Tabulating Machine Company. Most of the major census bureaus around the world leased his equipment and purchased his cards, as did major insurance companies. To make his system work he invented the first automatic card-feed mechanism, the first key punch (i.e. punch that was operated from a keyboard) allowing a skilled operator to punch 200-300 cards per hour, and a wiring panel in his 1906 Type I Tabulator allowing it to do different jobs without having to be rebuilt (the first step towards programming). The 1890 Tabulator was hardwired to operate only on 1890 Census cards. These inventions were the foundation of the modern information processing industry.
International Business Machines
In 1911 his firm merged with two others to form the Computing Tabulating Recording (CTR) Corporation. Under the presidency of Thomas J. Watson it was renamed IBM in 1924.
External links
" Hollerith's patents from 1889: U.S. Patent 395781 U.S. Patent 395782 U.S. Patent 395783
" More on Hollerith and his original tabulator
" Hollerith page at the National Hall of Fame
This article was originally based on material from the Free On-line Dictionary of Computing, which is licensed under the GFDL.
Timeline
" 1860 Birth of Herman Hollerith
" 1880 US Census in Manhattan
" 1890 US Census compiled with his tabulating machine
" 1929 Death of Herman Hollerith
The punched card predates computers considerably. As early as 1725 Basile Bouchon used perforated paper loop in a loom to establish the pattern to be reproduced on cloth, and in 1726 his co-worker Jean-Baptiste Falcon improved on his design by using perforated paper cards attached to one another, which made it easier to change the program quickly. The Bouchon-Falcon loom was semi-automatic and required manual feed of the program. Joseph Jacquard used punched cards in 1801 as a control device for the more automatic Jacquard looms, which met with great success.
Charles Babbage, who originated the idea of a programmable computer, adopted Jacquard's system of punched cards to control the sequence of computations in the design for his analytical engine in 1837 [1]. Such cards were used as an input method for the primitive calculating machines of the late 19th century. The version by Herman Hollerith, patented on June 8, 1887 and used with mechanical tabulating machines in the 1890 U.S. Census, was a piece of cardboard about 90 mm by 215 mm, with round holes. This was the same size as the dollar bill of the time, so that storage cabinets designed for money could be used for his cards. The early applications of punched cards all used specifically-designed card layouts. It wasn't until around 1928 that punched cards and machines were made "general purpose". In that year, punched cards were made a standard size, exactly 7-3/8 inch by 3-1/4 inch (187.325 by 82.55 mm), reportedly corresponding to the US currency of the day, though some sources characterise this assertion as urban legend.
To compensate for the cyclical nature of the Census Bureau's demand for his machines, Hollerith founded the Tabulating Machine Company (1896) which was one of three companies that merged to form IBM in 1911.
The IBM 80-column punching format, with rectangular holes, eventually won out over the UNIVAC 90-character format, which used 45 columns (2 characters in each) of 12 round holes. IBM (Hollerith) punched cards are made of smooth stock, .007 of an inch thick. There are about 143 cards to the inch thickness; a group of such cards is called a deck. Punch cards were widely known as just IBM cards.
Functional details
A reproducing punch, like this one from IBM, could make exact copies of a deck of cards.
The method is quite simple: On a piece of light-weight cardboard, successive positions either have a hole punched through them or are left intact. The rectangular bits of paper punched out are called chads. Thus, each punch location on the card represents a single binary digit (or "bit"). Each column on the card contained several punch positions (multiple bits).
IBM punch card format
The IBM card format, which became standard, held 80 columns of 12 punch locations each, representing 80 characters. Originally only numeric information was coded with 1 or 2 punchs per column: digits(digit[0-9]) and signs (zone[12,11] - sometimes overpunching the Least Significant Digit). Later, codes were introduced for upper-case letters and special characters. A column with 2 punches (zone[12,11,0] + digit[1-9]) was a letter; 3 punches
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